3 Important People in My Life.

3 important people in my life. There are several people in my life that have served as a source of influence. However, there are three people who have not only impacted a decision or two, but have drastically altered my way of life. These people have completely transformed my life in a positive way. Without these people, my life would not have the same meaning and purpose. These three important individuals are my mom, my dad, and my wife. First and foremost, there is my mother. She has served her role as my mother dutifully and out of love. That would explain any mother in this world.However, she has gone beyond that and has provided a very nurturing childhood while growing up. Growing up in India, there was a large emphasis on academic success. For some of my friends, that meant doing well and succeeding called for praise while failure was simply looked at with disgust. My mother never judged me for my successes or failures. She acknowledged my successes, but also taught me how to l earn with my failures. This applied not only to school, but also to sports. Perhaps, this is why I excelled in both. I received the encouragement and proper guidance I needed.Furthermore, my mom always had a calm attitude. She never worked with a hot temper. I learned how to be patient and how to deal with problems that came my way. Thus, my mom did not only provide me with an exemplary childhood, she role modeled and taught me positive life skills. I always refer back to a problem in terms of what my own mother would do. The second most significant person in my life is my father. Growing up, he was very present in my life even in a patriarchal society. He encouraged me to succeed and excel in everything I do.Not only that, but he also taught me some of the tougher life lessons. I remember that as a child, whenever I wanted something new, I had to wait it out until it was practical to replace whatever I wanted to replace. If I whined or cried, it would be completely out of the quest ion. Thus, my dad in a way taught me how to appreciate the things in life as the way they are instead of always hoping for a change. He also taught me to be strong and patient with goals because crying and whining only leads to time wasted. It is a weakness that only sets you back instead of moving you forward.Another aspect my dad has influenced me greatly is to look at every individual with equality. Growing up, I was raised to not judge a person based on who they were or how much money they made. My dad instilled these values into me and hoped that I carried them forward. He wanted me to understand that people may differ from the surface, but they should all be taken equally. Without my father, my social interactions and way of setting goals and achieving them would not have been the same. Finally, the final person of significance in my life is my wife of 4 years.Right after I moved to Houston, I did not know many people and my life was very simple and bland. I would go to school , focus on my studies, interact with my family, and repeat the same routine every single day. My life was missing an important social sector. I had no one else to talk to. However, I met a girl from Houston and she was very friendly and kind. She did not judge me like others did. She did not concern herself with my style or who I was. She took me like any other person. Perhaps this mindset was what I was looking for in another person.She not only was there when I needed her the most, but she became another reason and another motivation to keep my life moving strong. Thus, she has inspired me that there is always hope even in difficult times. However, the key is to maintain hope and a positive attitude. One of the most important things she has taught me is to always smile and life. Life is too short to carry a frown on your face and to not enjoy every single moment of it. As a result, these three people have served as great source of positive influence. Without them, my life would be incomplete.

Dadada

Food tech. Assessment Task Sensory characteristics of food. A. Appearance, the appearance of the caramelized apple tart was very good, the tart itself was a golden brown colour, the caramel apple mixture was a thick caramel brown colour which tasted really good, the serving of icecream on the side was left for a little bit to long as it began to melt which gave the whole overall appearance not such a great look. B. Color, the color of the caramelized apple tart was a mixture of deep golden-brown tarts with a caramel light brown apple sauce which was quite thick and a creamy white serve of half melted ice cream. These arrange of colors made the entire dish look very appealing due to the contrast of vibrant colors C. Aroma, the aroma of the caramelized apple tart was rich in flavorful smells. My senses were uplifted by the engaging aroma because it smelt so good. D. Taste, the taste of the caramelized apple tart was very satisfying, the constrasting of both cold ice cream and hot tart went down smoothly, ice cream was a little bit melted but this did not affect the taste in anyway, overall very tasty dish E. Texture, the texture of the caramelized apple tart was quite nice, the tart itself was smooth and slightly crispy. The apples in the caramel mixture were very soft and the caramel was a little bit thick. Ice cream was smooth but slightly melted. 3. Explain 3 functional properties that occur. Dextrinization is a process in which starch is converted into dextrins. Dextrin’s are any various polysaccharide which has been collected by the starch. This is made possible by the application of heat or acids. Dextrinization is mainly used as a thickening agent or a rising tool. Dextrinization occurs in Step 5 â€Å"bake for 15mins or until golden brown† this is referring to the puff pastry. Aeration is a process in which air comes into contact with a food. Aeration occurs in Step 6 during the Beating of the eggs. Denaturation is a process in which proteins loose their structures and denature because of external factors like heat or stress. Denaturing occurs in the protein strands of the eggs when they are beated until stiff, the eggs loose their structures and denature. 4. Make two recommendations for the improvement of the dish. If I could start over I would change the following; first I would use proper scales to measure ingredients correctly ather than eye guessing weights because I didn’t have proper scaling equipment. This would improve my final product because all ingredients would be correct measured out and this would finalise in a more accurate satisfying final dish. The second improvement I would make would have been not to leave the ice cream out because it began to melt. This would have helped to improve my dish because the the ice cream would have be en easier to eat as apposed to a liquid mess and the presentation would have looked a lot better. Thank You.

Over Reliance on Technology Essay

It’s 2010 and the human species as we know is in a monumental technological crossroads. Globally, we have defined the age of technological and industrial growth. As a whole our society has always been improving on all of the technological inventions to provide the general public with seamless automated and convenient applications to our personal and work life. In the age of pin size microchips and artificial intelligence the sky is the limit to our advancement of faster and more integrated technology. We as a society have embraced all of the new technological advancements and have integrated it throughout all aspects of human life. This over reliance on technology has taken away an aspect of human interaction that is vital to the way we have conducted ourselves in the past. It brings up many questions about the role technology is playing in our everyday lives. We seem to be on the constant search for ways that reduce the time worked. I-phones, Blackberry and other communication devices are always getting faster and more integrated. Specifically, the I-phone has applications that can be downloaded pertaining to just about anything. There is an application that can be downloaded that connects your I-phone to your house’s burglar alarm as well an application that can cipher passwords for alarm systems as well. Yes, I agree that this is the direction we have been catapulted in and it seems like there is not a safety net for us. Reliance on technology simply means that our personal world cannot function without the use of technological devices. According to a study done by National Public Radio, 68% of Americans say that they use a computer on the job. Of those 68%, 84% say that the use of a computer is crucial to their job being completed. (Mcphilson) A great example showing how technological advancements have taken away the human interactive experience involves the insurance industry. According to an article by Ara C Trembly, he explains how new customer service technology implemented by the major insurance companies across the United States has failed to live up to the satisfaction of the majority of these companies clients. He states â€Å"For example, at the beginning of this decade. Customer relationship management (CRM) technology was all the rage in insurance circles with carriers falling over each other trying to get (CRM) systems  implemented within there companies. As many now know, (CRM) was-on balance- a colossal flop in the insurance industry. It was a fully automated system that led clients through a corn maze of automated directions for the client. This idea was not accepted by the customers as a whole. It caused great confusion and landed most of the companies in hot water with there clients.† (Trembly) The main reason for the (CRM) failure was the lack of guidance for the clients and not being able to connect to a live representative in a timely manner to discuss there financial inquiries. The program was doomed from the beginning. What the insurance industry failed to realize was that the same visceral human interactive experience that secured the clients in the first place was being replaced with a robotic voice that cannot be spoken to. The public in general rejected this technological advancement due to a lack of human interaction. Further defending the viewpoint that over reliance on technology can be detrimental, an article by Shankar Vedantam explains what he describes as the â€Å"automation paradox†. He shows how disaster may erupt from over reliance on technology meant to minimize human error. Although, mainly addressing automated systems such as cruise control, he cites a cruise ship accident in which crewmembers were so trusting of their GPS that when the device accidently disconnected, the crew did not notice and simply followed the emergency plan route. He says â€Å"The problem is when individuals start to over trust or become complacent and put too much emphasis on the automation.† (Marcellus) It shows how we have become so reliant on technology especially, GPS, that we are not trained to detect if the information being relayed to the transmitter is correct or not. Back in the old maritime days before GPS and radar were available the captains and crew of all of the big ocean liners were well versed in charting maps, currents and reading compasses. The innovation of radar and sonar helped the skippers chart there courses more precisely. The invention of GPS basically allowed for complete course charts with limited crew interface. The GPS program would chart, estimate  fuel consumption and engage in autopilot so the duties of the maritime crews changed. The training is now eased with the use of computers and GPS. The real math calculations and degree settings that the crew would work as a team to produce is now being produced in seconds, not always correct I may add by a microchip and satellite. Humans are regressing in education and knowledge due to the over reliance on computers and technology. We seem to be embracing all of these technological advances without fully understanding the long term ramifications of this decision. We are constantly seeking out short term gains and improvements without really taking into consideration the whole big picture for future generations. As the absolute most vital connector we own, our computer as a tool is an amazingly useful aid. It has helped architects and engineers design and provide more reliable, interesting structures and buildings. It has allowed us to split atoms and categorize the human genome. Completely take the guesswork out of business intelligence and product demand curves. It even allows us to exchange money in the form of bits and bytes instead of actual paper money changing hands. As a foundation for an important economic pillar in our country we may heading for trouble. It is well known in the IT community that any computer can be hacked into. A question arises with amount of trust that you should put into this technology knowing that at any moment your computer could compromised by hackers and wrongdoers. We as a society have reached our capacity on our electrical grids. Being so reliant on electricity to run all of our new technological devices it sounds like a rather simple idea on how to bring down a modern day society. Cut the electric off. Talk about being thrown back into the early 1800’s real quick. As our thirst for electricity increases and our infrastructure fails to keep pace with demand we will be ultimately be forced to live like the pre-electric 1800’s era people. We as species have become very sedentary and non motile with all of our technological devices that make our lives easier but less interactive. The price we pay as a society will be enormous. Instead of trying to make our lives easier we should be developing ways to make the species as a whole more adaptative to new technology without losing the human interaction. (Technology Reliance) Maybe when it is all said and done we should have taken some meaningful advise from our Amish brother and sisters. According to an article by James Surowiecki of Technology Review â€Å"Amish people are less likely to have depression and are consistently happier than the rest of society. This is partly due to the strong community ties ,stable families and unchanging faith. Not believing in modern technology such as the Amish people believe made for reliance on there fellow man instead of a Blackberry. Towns would get together and build houses for the residents and providing what was needed to maintain a fruitful happy life. (Surowiecki) The Amish people make for a strong argument that technology does not have to be over relied upon. In conclusion, technology as we know and understand it is always compounding on itself. We as a society need to embrace the advancements of our great inventors but never forget the process it took to get that point. Technology without education is pointless. We can overcome this dilemma by not letting education standards go by the wayside while our technology races to infinity. Works Cited Page Marcellus, Jill. â€Å"Misled by GPS, Careless Drivers Reveal Dangers of Over-Reliance on Technology.† 30 July 2009. finding Dulcinea. . Mcphilson, Susan. National Public Radio. 28 July 2010. . Surowiecki, James. Technological Reveiw (2010). Technology Reliance. 6 July 2010. Trembly, Ara C. â€Å"Over Reliance on Technology is an Ever-Present Danger.† 18 August 2009: 2.

How would the likely discovery of aliens strike controversy among Research Paper

How would the likely discovery of aliens strike controversy among religions - Research Paper Example their existence, the fact that an alien visit may occur or human-alien encounter may be a possibility has led to panic from different quarters including religion. Movies and fictions films have continued to portray different picture of the events that may precede the invasion and how human and the aliens may relate during the process. Movies like the Independence Day and the visitors point at a negative image towards the encounter as the two forms of life may be keen to outdo each other on warfare and intelligence (Smith-Christopher 15). Apart from the war and intelligence impacts of alien strike, the impacts of such a possibility on religion has remained raw on theologizes and faithful alkies. According to the biblical teaching, man created human beings in his own likeness and no other forms of life are mention. This possibility could affect the faith of people in their religion and impact significantly to a shift especially in if the intelligence of the aliens is beyond that of human beings. In this paper, the impacts of an alien strike on religion across the globe will be examined. The paper will evaluate available theoretical discourse on the topic and how films and movies have depicted the reactions of Christians to alien invasion (Smith-Christopher 15). Within different religious groupings, the belief that a spiritual being out there is tasked with the role of ensuring our wellbeing has dominated since the history of man. The actions of religious leaders are believed to be under the command of the Supreme Being and this enable them to tell us the nature of the spirits and their impacts on life. The catholic church for, for example, has always expressed its zeal to impose monotheism in the world which is based on the trinity (Dunning 21). To achieve this, the church adopted a ruthless approach that suppressed the polytheists in Europe and the smaller kingdoms in the region. Among the Judeo-Christian, the possibility of the presence of a small but powerful

Innovation & Change Case Study Example | Topics and Well Written Essays - 1250 words

Innovation & Change - Case Study Example s that bring about a positive change to various aspects of the company such as its production levels, economic stability as well as growth in the particular market it is situated in (Davila, Epstein & Shelton, 2006). The activities that take place when trying to achieve these changes can be seen as the product of innovation by the company. It is especially essential for individuals dealing with innovation to realize the various methods and approaches that can be taken when dealing their implementation and management. The identification of these approaches allows a manger to select the most appropriate approach for their company and as a result enhance the chances of success a company has at attaining their objectives. The relationship between innovation and change comes into play as a result of the effects that a particular action may have on a company (Fichter, 2009). It also brings about the question of how important a role innovation plays in the growth of a company and whether this growth can be achieved minus the involvement of innovative approaches applied by the mangers. In order to fully answer these questions, one has to look at a particular company and the innovative implementations involved when looking to promote a positive impact on the organization (Heyne, Boettke & Prychitko, 2010). An industry that can be used to further expound on this concept is the vehicle industry with a leading company such as Toyota being the topic of the study to determine the role that innovation plays in the growth of a company. It should be noted that despite the fact that innovation is an important element in itself, the management of these innovations determines the success that an individual is able to enjoy in the resulting outcome. There are various ways that innovation can be considered important in regards to the development and growth of a company. The key aspect that plays a role in this essentialness is the point that an organization cannot remain stagnant in

New Hire Education Tool Assignment Example | Topics and Well Written Essays - 500 words

New Hire Education Tool - Assignment Example Main areas of work include concept image and principles to maintain evidence-based culture in health care, research and education. By the analysis of patient data, nurses are able to create interventions that greatly improve the patients overall health (Saba, 2005). The main goal of nursing informatics and quality data management is the creation of a competent information management system that can readily accumulate and retrieve data that is related to the daily manner of a nurses work. Creating a system like this is important so that a nurse in a certain the country or world can easily access pertinent information that may have been accumulated in a far-away workplace. It is the liability of nursing informatics practitioners to expand these systems using the most recent information and computer technologies available. Nurses and other medical officers usually learn through personal experiences. Nevertheless, these medical professionals can also become skilled through the experiences of other individuals in their field. On a daily basis in thousands of diverse settings and scenarios, including medical clinics, doctors offices and hospitals, nurses encounter situations and setups they may not have encountered before. However, with the counsel and advice of those around them, they discover ways to deal with the issue and move on. By shortly documenting the condition, the explanation they chose and the decisive outcome and by documenting the information electronically, they make a road map that others in the field of medicine can pursue when they encounter parallel situations (Akay, 2001). Since the largest part, if not all, of the data and information produced in the field of nursing is delicate and sensitive, specifically to the degree that it includes data and information about exact patients, the expansion of nursing informatics systems is

Applied research methods for Business and management Essay

Applied research methods for Business and management - Essay Example The 2006 record high of global acquisitions indicates the rampancy of Mergers and Acquisitions in the recent past (Saigol and Politti, 2007). The value of worldwide acquisitions stood at more than 4 trillion US dollars in this year. Out of the 4 trillion US dollars, 1.3 trillion US dollars worth of acquisitions were cross-border Mergers and Acquisitions (Saigol and Politti, 2007). The consistency of the trend spread to the first fiscal quarter of 2007 when acquisitions were valued at 1.13 trillion US dollars; making this fiscal quarter the busiest in the history of acquisitions (Henry, 2002). The value of completed acquisitions in the past two decades exceeds that of completed deals in the prior 30 years (Child et al., 2001). However, this recent upsurge comes along with the fact that about 80 percent of acquisition deals are unsuccessful (KPMG, 1999). Most empirical studies suggest that the reason for the immense failure in acquisitions is majorly the acquirers’ poor anticipation of the most probable challenges in the post-acquisition stages (Shimizu et al., 2004). The high failure rates coupled with the simultaneous high rampancy of acquisition transactions makes the concept of Mergers and Acquisitions an unexplained paradox (Arika, 2004). Academic and economic research efforts indicate that despite the failure of most acquisitions to achieve the objectives set in the pre-acquisition stage, Cross-border Mergers and Acquisitions continue being popular and remain the main strategy multinational corporations use to invest directly in foreign countries (Rottig and Reus, 2005). The concurrent successes and failures of Cross-border Mergers and Acquisitions beg for a well-targeted research study to examine the main causal factors for the high failure rates (Larsson and Risberg, 1998). Additionally, while numerous research hours have been devoted to the study of Cross-border

John R. Dilworth Animator Research Paper Example | Topics and Well Written Essays - 2000 words

John R. Dilworth Animator - Research Paper Example Within the spectrum of animation a number of prominent artists have emerged who have revolutionized the genre or simply create meaningful and unique content. One such animation artist is John R. Wilworth. This essay constitutes a broad ranging investigation of Wilworth’s background and professional development and analyzes some of his prominent films in the context of his oeuvre and the animation tradition. Analysis John R. Dilworth was born February 14, 1963 in New York City, New York. Growing up he had been interested in arts and animation and notes that he spent countless hours watching Disney films and attempting to replicate characters such as Donald Duck and Mickey Mouse for his high school art projects. He came to recognize that he had both a talent and inclination for this variety of artistic expression and resolved to pursue a career in arts and animation. He attended the School of Visual Art in New York. While he avidly pursued his scholastic pursuit, he also has not ed that, â€Å""You can't rely on a school to teach you what you believe you should know. You need to take the responsibility† (Miller, 1999). ... The position was lucrative for Dilworth, especially after recently graduating from college. Still, he recognized that working as an art director was not his true passion in life and longed for a full-time career in animation. Pursuing a career in animation became Dilworth’s primary driving impulse. Using his salary at Baldi, Bloom and Whelan Advertising Dilworth began funding his own animated projects. Among the most prominent pursuits during this time was he work on what he refers to as his magnum opus The Limited Bird. For two and a half years every night after work Dilworth would go home and work on this film. After completing the film Dilworth was able to shop it to potential employers as a means of beginning his career in animation. In these regards, Dilworth began working for a variety of animations studios as an assistant or cel painter. While he was not creating his own work, the experience was crucial in his development as it allowed Dilworth to further enhance his an imation skills as well as gain an understanding of the structural dimensions of the animation business. During this period Dilworth worked for a number of prominent animation studios, perhaps most prominent Nickelodeon where he worked on the original version of the popular Doug cartoon. As Dilworth’s gained further experience with the animation studios he gradually took on greater responsibility. In these regards, he completed work on When Lilly Laney Moved In (1991), as well as Psyched for Snuppa (1992). While Dilworth’s career responsibilities were gradually increasing he began to further refine his perspective on style and artistic production. He notes that during this period he came to recognize to, â€Å"see

Wk 5 discus Essay Example | Topics and Well Written Essays - 750 words

Wk 5 discus - Essay Example Since the relationship between the counselor and the individual is going well, the counselor should not have "pretended" that they knew about it. Instead, it should have been a topic that was discussed in the session. Resolving the presenting issues is not possible because of the lack of knowledge. A counselor in this situation must be careful because their ideas and values will be challenged by this practice. It is not likely that this woman will adopt the American way of being or that she will accept that she should not complete the practice. What the counselor can do is help her to examine the choice and all of the issues surrounding it but ultimately the client will need to make the choice. The counselor must be in an emotional space for themselves that allows the client to make her decision without coercion by the counselor. As much as this is a terrible and demeaning practice for women, it is not something that is going to change overnight. If the counselor can assist the client emotionally in going through with the process or emotions after it (if she decides to go through with it) this would be the most beneficial way for both the client and the counselor. Female circumcision is not right and it is terrible for the individual but it is something that many women are cul turally bred to

Alia Malek, Patriot Acts. Book Essay Example | Topics and Well Written Essays - 500 words

Alia Malek, Patriot Acts. Book - Essay Example Where of how law enforcement officers bully normal citizens, as well as how normal citizens bully other citizens who they consider are much lesser than them in a number of aspects such as race and colour. We hear of bullying stories every day in our schools. Students from different races (rather than whites) and deprived backgrounds among others fall prey to mostly white students who consider themselves more superior to other races (Bacon 35). I also fell prey to some of the worst bullies while in high school. It shows so evidently the role of our lack of knowledge as a country and as humans. I find both enraging and heartbreaking that parents, teachers, as well as schools, can be the major persecutors in a majority of these stories. The stories of Gurwinder and Rana truly drove the cultural unawareness home, but my own ignorance, as well: I echoed on the rage of my Sikh or Muslim friends and how immature I was of what they were enduring from the entire nation while they were going t hrough persecution in other regions of the globe I am delighted to have stumble upon this volume. The stories in Patriot Acts cope with one basic issue: what defines an American? Can United States citizens put on turbans? And can they pray openly? The storytellers in this volume are being deprived of their Americanism (which is that different when compared to citizenship) and, in the United States, that means that they are being shorn of their humanity (Malek 56). I marvel if this tendency to link Americanism with basic humanity is exclusive to the United States or if other nations are no different. A brand of American patriotism is to associate America with liberty, as well as freedom with ones fundamental rights (Bacon 40). However this principle, the highest confidence Americans have in this thought, depends on that liberty being indivisible from their citizens and not only the government. So how do individuals’ freedoms get

Research Design DB Essay Example | Topics and Well Written Essays - 500 words

Research Design DB - Essay Example The said actions resulted to a vicious cycle of manipulating records to be able to present a continuous growth of the company (Fusaro, Miller, & James, 2002). Basically, the misrepresentation of the company records can be considered as an escalating problem that is a continuous threat to the company’s survival. The fraud has been kept for long due to the fact there is an existence of accounts in other countries that were able to hide the real losses of the company. In the absence of such accounts, the manipulation of the records cannot be possible. On the other hand though, although the said actions are carefully undertaken, the unconventional presentation of records continuously raised suspicion until the said company finally collapsed due to the lack of supporting assets (Fusaro, Miller, & James, 2002). The misuse of the data by Enron can be considered to benefit the reputation and the price of the stocks during the particular time. The company had been able to continuously lead the market although loses can be considered substantial. The said loses which are well hidden during that time had been the cause of the fall of the company. Every data that are related to finding out the crimes committed limits the operation of the company (Bazerman, 2006; Fusaro, Miller, & James, 2002). In relation the ethical implications of the Enron case, the fraud and deceit of the different parties that are involved can be considered as the main issue. Basically, any misrepresentation of data specifically in business organizations can be ethically questioned. The fact that the company lacks the real assets that amounts to the values represented in the records can be considered as the main basis of the bound failure of Enron. In addition, the ethical implications of such actions of the financial personnel can be considered of detrimental effects in any business

Malware Discussion Essay Example for Free

Malware Discussion Essay The use of malware is a way for attackers to gain access to person information from a personal computer or company information from an organization. There are several types of malware which include virus, rootkits, and worms. Each malware serves different purposes to achieve the goal of an attacker. An attacker could be envious of a past lover and could send a virus to their email to shutdown the operations of their computer. A disgruntle employee could send a worm to their old company and slow down production of the company. A random person looking for a thrill could set up a rootkit on a company’s network to gain access to company secrets. Each malware is given a name specified for its cause, for example the Trojan Worm. The name is given to this virus because of the activity that happens once it is executed. Viruses are named by antivirus companies who avoid using proper names. The Melissa virus was named by its creator, David Smith, for a Miami stripper. This paper will discuss 5 different types of malware and inform the targets for these attacks. Discussion of Malware The first malware that will be discussed is the Melissa Virus. This virus was detected on the 26th of March 1999. This virus is a Microsoft Word macro virus that is delivered as an E-mail attachment. The virus is activated when an attachment named, list. doc is opened. When it is activated, the Melissa virus searches the Microsoft Outlook address book and sends a message to the first 50 names. This virus proliferates itself as users open the attachment. Melissa doesn’t work on Outlook Express, just Outlook. The message appears to come from the person just infected, which means that the message will seem to come from a recognizable email address. Melissa doesn’t destroy files or other resources, but has the possibility to immobilize corporate and other mails servers. The origin of the Melissa virus is from an Internet alt. sex newsgroup and contains a list of passwords for various Web sites that require memberships. Melissa also has the ability to disable some security safeguards. Users of Microsoft Word 97 or 2000 with Microsoft Outlook 97, 98, or 200 are most likely to be affected. When the virus attacks, it can infect the copy of Microsoft Word that is installed as well as any following Word documents that are created. It can also change the setting of Microsoft Word to make it easier for the computer to become infected by it and succeeding macro viruses. Users of Word 97 or 2000 containing any other E-mail programs can be affected also; the difference is that Melissa will not automatically redistribute itself to the contacts through other E-mail programs. It can still however infect the copy of Microsoft installed on the machine. This infected copy can still be shared with others if a document is created in the infected copy and distributed through E-mail, floppy disk, or FTP. Although the virus won’t appeal to the mailout on a Mac system, it can be stored and resent from Macs. To avoid this virus, it is suggested to not double-click any file, such as an E-mail attachment, without scanning it first with antivirus software, regardless of who it is from. The next malware to be discussed is SQL injection which is an attack where malicious code is placed in within strings that are shortly passed on to an example of SQL Server for parsing and implementation. A form of SQL injection consists of direct placing of code into user-input variables that link with SQL commands and executed. An attack that is not as direct, inserts malicious code into strings that are intended for storage in a table or as metadata. The malicious code is executed once the stored strings are linked into a dynamic SQL command. In SQL Injection, the hacker uses SQL queries and ingenuity to get to the database of susceptible corporate data through the web application. Websites with features as login pages, support and product request forms, feedback forms, search pages, shopping carts and the general delivery of dynamic content, shape modern websites and provide businesses with the means necessary to communicate with prospects and customers are all vulnerable to SQL Injection attacks. The reason behind this is because the fields available for user input allow SQL statements to pass through and query the database directly. SQL Injection flaws are introduced when software developers create dynamic database queries that include user supplied input. There have been several reports of SQL attacks, dating back to 2005. The websites that have became victim to these attacks range from Microsoft U. K. to Lady GaGa’s website. To avoid SQL injection flaws, it is suggested that developers need to either: a) stop writing dynamic queries; and/or b) prevent user supplied input which contains malicious SQL from affecting the logic of the executed query. The next malware discussed will be Stuxnet. Stuxnet is a computer worm that targets Siemens industrial software and equipment running Microsoft Windows, and was discovered in June 2010. Although Stuxnet isn’t the first attack to target industrial systems, it is however the first discovered malware that actually moles on and weakens industrial systems. Stuxnet is also the first malware to include a programmable logic controller rootkit. Stuxnet is designed to target specifically Siemens supervisory control and data acquisition systems that are configured to control and monitor specific industrial processes. The PLCs are infected by Stuxnet weakening the Step-7 software application that is used to reprogram these devices. Stuxnet is different from other malware as it only attacks computers and networks that meet a specific configuration requirement. Stuxnet contains a safeguard and if Siemens software isn’t discovered on the infected computer will prevent each infected computer from spreading the worm to more than three others, and to erase itself on June 24, 2012. Along with other things for its victims, Stuxnets contains code for a man-in-the-middle attack. Stuxnet will spread through removable devices such as an USB drive in a Windows operating system by using a four zero-day attack. After it has infected the removable drive, it uses other utilizations and techniques to infect and update other computers inside private networks. Stuxnet infects Step 7 software by infecting project files belong to Siemen’s WinCC/PCS 7 SCADA control software and weakens a key communication library of WinCC called s7otbxdx. dll. It is recommended by Siemens to contact customer support if and infection is detected and advises installing Microsoft patches for security vulnerabilities and prohibiting the use of third-party USB flash drives. Next, Zeus, also known as Zbot virus will be discussed. This virus is geared toward financial institutions such as banks. Zeus was first discovered in July 2007 after being used to steal information from the US DOT. Zeus is set up to infect a consumers PC, and wait until the log onto a list of targeted banks and financial institutions and steal their credentials and sends them to a remote server in real time. Zeus can also inject HTML into a page that is provided by the browser, this displays its own content instead of the actual page from the bank’s web server. By doing this, it is able to obtain users information such card numbers and pins. According to SecureWorks, ZeuS is sold in the criminal underground as a kit for around $3000-4000, and is likely the one malware most utilized by criminals specializing in financial fraud. According to Lucian Constantin, Zeus is one of the oldest and most popular crimeware toolkits available on the underground market. Up until this year the Trojan could only be acquired for significant sums of money from its original author. However, a few months ago the source code leaked online and now anyone with the proper knowledge can create variations of the malware. Also according to SecureWorks, The latest version of Zeus as of this date is 1. 3. 4. x and is privately sold. The author has gone to great lengths to protect this version using a Hardware-based Licensing System. The author of Zeus has created a hardware-based licensing system for the Zeus Builder kit that you can only run on one computer. Once you run it, you get a code from the specific computer, and then the author gives you a key just for that computer. This is the first time they have seen this level of control for malware. The CTU recommends that businesses and home users carry out online banking and financial transactions on isolated workstations that are not used for general Internet activities, such as web browsing and reading email which could increase the risk of infection. The last malware that will be discussed is the Blaster worm also known as Lovsan, Lovesan, or MSBlast. The Blaster worm spreads on computers that have Windows XP and Windows 2000 as an operating system and was detected in August of 2003. The creator of the B variant of the Blaster worm, Jeffrey Lee Parson was an 18 year old from Hopkins, Minnesota. He was arrested on August 29, 2003, admitted to the creation of the B variant, and was sentenced to 18-months in prison in January 2005. A Windows component known as the DCOM (Distributed Component Object Model) interface which is a known vulnerability of Windows is taken advantage of by Blaster. The DCOM handles messages sent using the RPC (Remote Procedure Call) protocol. Vulnerable systems can be compromised without any interaction from a user, according to Johannes Ullrich, chief technology officer at the SANS Internet Storm Center, which monitors threats to the Internet infrastructure. According to Mikko Hypponen, manager of antivirus research at F-Secure in Helsinki, Blaster unlike the Code Red worm, which contained code for a similar attack against the IP address of White House’s main Web server, targets the windowsupdate. microsoft. com domain, which prevents Microsoft from changing the address of the domain to sidestep the attack. Blasters code is small and can be quickly removed using free tools provided by F-Secure as well as other antivirus vendors, Hypponen said. However, customers should patch their systems before removing Blaster to prevent from getting infected again from the worm, he said.

Effectiveness of Video Assisted Teaching for Medical Student

Effectiveness of Video Assisted Teaching for Medical Student CHAPTER IV DATA ANALYSIS AND INTERPRETATION This chapter deals with analysis and interpretation of data collected to evaluate the effectiveness of video assisted teaching programme regarding successful ventilation with the I-gel and Laryngeal mask Airway among the paramedical students. The purpose of the analysis is to reduce the data as manageable and interpretable form, so that the research problem can be suited and tested. The collected data are tabulated, organized and analyzed by using descriptive and inferential statistics. Section–A: Distribution of paramedical students according to their selected demographic variables. Section-B: Distribution of paramedical students according to pretest scores on knowledge regarding successful ventilation with I-gel and Laryngeal Mask Airway. Distribution of paramedical students according to pretest scores on skill regarding successful ventilation with I-gel and Laryngeal Mask Airway. Section-C: Distribution of paramedical students according to posttest scores on knowledge regarding successful ventilation with I-gel and Laryngeal Mask Airway. Distribution of paramedical students according to posttest scores on skill regarding successful ventilation with I-gel and Laryngeal Mask Airway. Comparison between the pretest and posttest scores on knowledge regarding successful ventilation with I-gel and Laryngeal Mask Airway among paramedical students. Comparison between the pretest and posttest scores on skill regarding successful ventilation with I-gel and Laryngeal Mask Airway among paramedical students. Area wise comparison between the pretest and the posttest scores on knowledge regarding successful ventilation with I-gel and Laryngeal Mask Airway among paramedical students. Area wise comparison between the pretest and the posttest scores on skill regarding successful ventilation with I-gel and Laryngeal Mask Airway among paramedical students. Comparison between the pretest and the posttest scores on knowledge and skill regarding successful ventilation with I-gel and Laryngeal Mask Airway among paramedical students. Section-D: Effectiveness of video assisted teaching programme on knowledge and skill regarding successful ventilation with I-gel and Laryngeal Mask Airway among paramedical students. Relationship between pretest and posttest scores on knowledge and skill regarding successful ventilation with I-gel and Laryngeal Mask Airway among paramedical students. Association between the pretest scores on knowledge and skill regarding successful ventilation with I-gel and Laryngeal Mask Airway among paramedical students and their selected demographic variables. Section A Distribution of paramedical students according to their demographic variables. Table 4.1: The frequency and percentage distribution of paramedical students according to their selected demographic variables. n=50 S.No Demographic variables f % 1 Age in years 17-19 20-22 23-25 22 23 5 44 46 10 2 Gender Male Female 34 16 68 32 3 Religion Hindu Muslim Christian Any other 31 12 7 0 62 20 18 0 4 Category of course of study B.Sc Critical care B.Sc physician assistant 31 19 62 38 5 Previous knowledge Yes No 40 10 80 20 6 If yes how did you obtain information By attending classes By attending airway management courses Through television Through internet 22 7 9 2 48 16 22 14 Table-4.1 Table 4.1 describes that distribution of paramedical students according to their demographic variables. According to their age most of the paramedical students, 22(44%) are in the age group of 17-19 years, 23(46%) are aged between 20-22 years and 5(10%) are aged between 23-25 years. Among 50 paramedical students according to their gender, majority of the paramedical students 34(68%) are male and 16(32%) of them are female. Among 50 paramedical students according to their religion, majority of the paramedical students 31(62%) are Hindus and 12(20%) of them are Muslim. 7(18%) paramedical student is Christian and none of the paramedical students belong to other religion category. Paramedical students according to their category of course of study, 31(62%) of them studying in Bachelor of Science in Critical Care, 19(38%) of them studying in Bachelor of Science in Physician Assistant. Paramedical students according to their previous knowledge regarding airway management, more than half of the paramedical students 40(80%) has previous knowledge regarding airway management and 10(20%) of paramedical students do not have previous knowledge regarding airway management. Paramedical students according to their previous knowledge regarding airway management, among 40 paramedical students, who have previous knowledge regarding airway management, more than half of them 22(48%) have gained knowledge by attending classes, 7(16%) have gained knowledge by attending airway management classes, 9(22%) have gained knowledge through television, 2(14%) of them have gained knowledge through internet. Section-B a) Distribution of paramedical students according to pretest scores on knowledge regarding successful ventilation with I-gel and Laryngeal Mask Airway. Figure-4.1: Percentage distribution of paramedical students according to pretest scores on knowledge regarding successful ventilation with I-gel and Laryngeal Mask Airway. The above bar diagram shows that 34(68%) paramedical students have inadequate knowledge, 16(32%) paramedical students have moderately adequate knowledge and none of them have adequate knowledge regarding successful ventilation with I-gel and Laryngeal Mask Airway in their pretest. b) Distribution of paramedical students according to pretest scores on skill regarding successful ventilation with I-gel and Laryngeal Mask Airway. Figure-4.2: Percentage distribution of paramedical students according to pretest scores on skill regarding successful ventilation with I-gel and Laryngeal Mask Airway. The above bar diagram shows, among 50 paramedical students none of the paramedical students have good skill, 15(30%) paramedical students have average skill and 35(70%) of them have poor skill regarding successful ventilation with I-gel and Laryngeal Mask Airway in their pretest. Section: C a) Distribution of paramedical students according to posttest scores on knowledge regarding successful ventilation with I-gel and Laryngeal Mask Airway. Figure-4.3: Percentage distribution of paramedical students according to posttest scores on knowledge regarding successful ventilation with I-gel and Laryngeal Mask Airway. The above bar diagram shows that 42(84%) paramedical students have adequate knowledge and 8(16%) of them have moderately adequate knowledge regarding I-gel and Laryngeal Mask Airway. None of them have inadequate knowledge regarding successful ventilation with I-gel and Laryngeal Mask Airway in their posttest. b) Distribution of paramedical students according to posttest scores on skill regarding successful ventilation with I-gel and Laryngeal Mask Airway. Figure-4.4: Percentage distribution of paramedical students according to posttest scores on skill regarding successful ventilation with I-gel and Laryngeal Mask Airway. The above bar diagram shows, among 50 paramedical students none of them have poor skill, 7(14%) of them have average skill 43(86%) of them have good skill regarding successful ventilation with I-gel and Laryngeal Mask Airway in their posttest. c) Comparison between the pretest and posttest scores on knowledge regarding successful ventilation with I-gel and Laryngeal Mask Airway among paramedical students. Figure: 4.5 Percentage distributions according to their pretest and posttest scores on knowledge regarding successful ventilation with I-gel and Laryngeal Mask Airway among paramedical students The above bar diagram shows that 34(68%) paramedical students have inadequate knowledge, 16(32%) paramedical students have moderately adequate knowledge and none of them have adequate knowledge regarding successful ventilation with I-gel and Laryngeal Mask Airway in their pretest, Where as in post test, 42(84%) paramedical students have adequate knowledge and 8(16%) of them have moderately adequate knowledge, none of them have inadequate knowledge regarding successful ventilation with I-gel and Laryngeal Mask Airway when compared with pretest. Hence it highlights that there is a significant improvement in the knowledge regarding successful ventilation with I-gel and Laryngeal Mask Airway is improved compared to pre test. d) Comparison between the pretest and posttest scores on skill regarding successful ventilation with I-gel and Laryngeal Mask Airway among paramedical students. Figure: 4.6 Percentage distributions according to their pretest and posttest scores on skill regarding successful ventilation with I-gel and Laryngeal Mask Airway among paramedical students. The above bar diagram shows, among 50 paramedical students none of the paramedical students have good skill, 15(30%) paramedical students have average skill and 35(70%) of them have poor skill regarding successful ventilation with I-gel and Laryngeal Mask Airway in their pretest. Where as in the posttest, none of them have poor skill, 7(14%) of them has average skill 43(86%) of them have good skill regarding successful ventilation with I-gel and Laryngeal Mask Airway in their posttest and compared with posttest. Hence it highlights that there is a significant improvement in the skill regarding successful ventilation with I-gel and Laryngeal Mask Airway was improved in the posttest, when compared to pre test. e) Area wise comparison between the pretest and the posttest scores on knowledge regarding successful ventilation with I-gel and Laryngeal Mask Airway among paramedical students. Table – 4.2: Mean, standard deviation, mean percentage and difference in mean percentage of pretest and posttest scores on knowledge regarding successful ventilation with I-gel and Laryngeal Mask Airway among paramedical students in pretest and posttest. n=50 Area wise Maximum score Pretest Posttest Difference in mean % Mean S.D Mean% Mean S.D Mean % General information 9 5.9 1.55 65.5 8.08 0.71 89.7 24.2 I-gel 9 3.78 1.65 42 6.54 1.51 72.6 30.6 Laryngeal Mask Airway 12 5.26 1.77 43.8 8.96 1.29 74.6 30.8 Overall 30 14.94 4.97 151.3 23.58 3.51 236.9 85.6 The above table shows that, in area of general information the pre test mean score is 5.9 ±1.55 and mean percentage is 65.5, where as in the post test mean score is 8.08 ±0.71 and mean percentage is 89.7. This reveals that the difference in mean percentage is 24.2. In the area of I-gel the pre test mean score is 3.78 ±1.65 and mean percentage is 42, where as in the post test mean score is 6.54 ±1.51 and mean percentage is 72.6. This reveals that the difference in mean percentage is 30.6. In the area of Laryngeal mask airway the pre test mean score is 5.26 ±1.77 and mean percentage is 43.8, where as in the post test mean score is 8.96 ±1.29 and mean percentage is 74.6. This reveals that the difference in mean percentage is 30.8. In the pretest, the overall mean score is 14.94 ±4.97. In the pretest, the highest mean score is achieved in the general information with the score of 5.9 ±1.55. It reveals that difference in mean percentage is 24.2. In the post test, overall mean score is 23.58 ±3.51. The highest score is achieved in the Laryngeal Mask Airway with the score of 8.96 ±1.29. The overall difference in mean percentage is 85.6. The mean difference reveals that there is significant improvement in the knowledge in post test. f) Area wise comparison between the pretest and the posttest scores on skill regarding successful ventilation with I-gel and Laryngeal Mask Airway among paramedical students. Table – 4.3: Mean, standard deviation, mean percentage and difference in mean percentage of pretest and posttest scores on skill regarding successful ventilation with I-gel and Laryngeal Mask Airway among paramedical students in pretest and posttest n=50 Area wise Maximum score Pretest Posttest Difference in mean % Mean S.D Mean % Mean S.D Mean % I-gel 14 7.08 1.03 50.5 12.08 1.33 86.2 35.7 Laryngeal Mask Airway 16 7.82 1.19 48.8 13.54 1.43 84.6 35.8 Overall 30 14.9 2.22 99.3 25.62 2.76 170.8 71.5 The above table shows that In the area of I-gel the pre test mean score is 7.08 ±1.03 and mean percentage is 50.5, where as in the post test mean score is 612.08 ±1.33 and mean percentage is 86.2. This reveals that the difference in mean percentage is 35.7. In the area of Laryngeal mask airway the pre test mean score is 7.82 ±1.19 and mean percentage is 48.8, where as in the post test mean score is 13.54 ±1.43 and mean percentage is 84.6. This reveals that the difference in mean percentage is 35.8. In the pretest, over all mean score is 14.9 ±2.22. The higher percentage of the pretest is achieved in the Laryngeal Mask Airway, where the mean score is 7.82 ±1.19 with the difference in mean percentage of 35.8. In the post test, the overall mean score was 25.62 ±2.76. The highest mean score is achieved in the area of laryngeal mask airway with the score of 13.54 ±1.43. The overall difference in mean percentage is 71.5. This reveals that there is significant improvement in the post test on skill than the pretest. g) Comparison between the pretest and the posttest scores on knowledge and skill regarding successful ventilation with I-gel and Laryngeal Mask Airway among paramedical students. Table – 4.4: Comparison between the mean, SD, mean difference of pretest and the post test scores on knowledge and skill regarding successful ventilation with I-gel and Laryngeal Mask Airway Among the paramedical students. n=50 S.No Variables Maximum score Pretest Posttest Difference in mean % Mean S.D Mean% Mean S.D Mean % 1 Knowledge 30 14.94 2.99 49.8 23.58 2.50 78.6 28.8 2 Skill 30 14.9 1.72 49.7 25.62 2.31 85.4 35.7 The above table shows that in pretest, the knowledge mean score is 14.94 ±2.99 and the mean percentage is 49.8%. Where is posttest, the knowledge mean score is 23.58 ±2.50 and the mean percentage is 78.06%. The difference in mean percentage between the pretest and the posttest was 28.8%. In pretest, the skill mean score is 14.9 ±1.72 and the mean percentage is 49.7%. Where is posttest, the skill mean score is 25.62 ±2.31 and the mean percentage is 85.4%. The difference in mean percentage between the pretest and the posttest is 35.7%. It shows that in posttest there is significant improvement in knowledge and skill when compared to the knowledge and skill in pretest. Section D a) Effectiveness of video assisted teaching programme on knowledge and skill regarding successful ventilation with I-gel and Laryngeal Mask Airway among paramedical students. Table – 4.5: The mean, SD and ‘t’ value on knowledge and skill regarding successful ventilation with I-gel and Laryngeal Mask Airway among paramedical students in pretest and posttest. n=50 S.No Variables Maximum score Pretest Posttest Paired ‘t’ value Df Mean SD Mean SD 1 Knowledge 30 14.94 2.99 23.58 2.50 15.74 49 2 Skill 30 14.9 1.72 25.62 2.31 30.63 *significant at p≠¤0.05 level Table value: 2.02 The above table shows the pre test knowledge Mean score is 14.94 ±2.99 and the posttest knowledge mean score is 23.58 ±2.50. The Skill mean score in the pretest is 14.9 ±1.72 and the posttest skill mean score is 25.62 ±2.31. The Obtained‘t’ value for knowledge and skill is 15.74 and 30.63 respectively, which is significant at p≠¤0.05 level. Hence the hypothesis H1 was retained. Thus it becomes evident that Video Assisted Teaching Programme is effective in improving the knowledge and skill regarding successful ventilation with I-gel and Laryngeal Mask Airway among the paramedical students b) Relationship between pretest and posttest scores on knowledge and skill regarding successful ventilation with I-gel and Laryngeal Mask Airway among paramedical students Table – 4.6: Correlation between the pretest and the post test scores on knowledge and skill regarding successful ventilation with I-gel and Laryngeal Mask Airway among the paramedical students. n=50 S.No Group Knowledge Skill ‘r’ Mean SD Mean SD 1 Pretest 14.94 2.99 14.9 1.72 0.41 2 Posttest 23.58 2.50 25.62 2.31 0.65 The above table shows that, in the pretest mean score of knowledge and skill is 14.94 ±2.99 and 14.9 ±1.72 respectively, ‘r’ value was 0.41. The posttests mean score of knowledge and skill is 23.58 ±2.50 and 25.62 ±2.31 respectively, ‘r’ value is 0.65. This reveals that there is positive correlation between the pretest and the posttest knowledge and skill regarding successful ventilation with I-gel and Laryngeal Mask Airway among paramedical students. Hence the formulated hypothesis H2 was retained at p≠¤0.05 level. c) Association between the pretest scores on knowledge and skill regarding successful ventilation with I-gel and Laryngeal Mask Airway among paramedical students and their selected demographic variables. Table – 4.7: Chi Square test on the knowledge regarding successful ventilation with I-gel and Laryngeal Mask Airway among the Paramedical Students with their selected Demographic Variables. n=50 S.No Demographic variables à ¯Ã‚ Ã‚ £2 Df Table value 1 Age 2.76 2 5.99 2 Gender 0.06 1 3.84 3 Religion 2.21 3 7.82 4 Category of course 0.001 1 3.84 5 Previous knowledge 0.023 1 3.84 6 If yes how did you obtain information 1.60 3 7.82 *significant at p≠¤0.05 level The above table shows that there is no association between pretest score on knowledge regarding successful ventilation with I-gel and Laryngeal Mask Airway among paramedical students and their selected demographic variables such as Age, gender, religion, category of course of study, and previous knowledge. Hence the research hypothesis H3 was rejected at p≠¤0.05 level. Table – 4.8: Chi square test on the skill regarding successful ventilation with I-gel and Laryngeal Mask Airway among Paramedical Students with their selected demographic variables. n=50 S.No Demographic variables à ¯Ã‚ Ã‚ £2 Df Table value 1 Age 0.27 2 5.99 2 Gender 0.63 1 3.84 3 Religion 1.04 3 7.82 4 Category of course 0.03 1 3.84 5 Previous knowledge 0.59 1 3.84 6 If yes how did you obtain information 1.18 3 7.82 *significant at p≠¤0.05 level The above table shows that there is no association between pretest score on skill regarding successful ventilation with I-gel and Laryngeal Mask Airway among paramedical students and their selected demographic variables such as Age, gender, religion, category of course of study, and previous knowledge. Hence the research hypothesis H3 was rejected at p≠¤0.05 level. Summary: This chapter deals with the data analysis and interpretation in the form of statistical values based on the objectives, frequency and percentage on the knowledge and skill regarding successful ventilation with I-gel and Laryngeal Mask Airway among paramedical students and their selected demographic variables analyzed. The‘t’ test is done to evaluate the effectiveness of video assisted teaching programme on knowledge and skill regarding successful ventilation with I-gel and Laryngeal Mask Airway among Paramedical Students. The chi-square analysis is used to find out the association between the pretest scores on knowledge and skill regarding successful ventilation with I-gel and Laryngeal Mask Airway among the Paramedical students and the selected demographic variables.

Model for Predicting Fatigue Life of Nanomaterials

Model for Predicting Fatigue Life of Nanomaterials Introduction In the past, the primary function of micro-systems packaging was to provide input/output (I/O) connections to and from integrated circuits (ICs) and to provide interconnection between the components on the system board level while physically supporting the electronic device and protecting the assembly from the environment. In order to increase the functionality and the miniaturization of the current electronic devices, these IC devices have not only incorporated more transistors but have also included more active and passive components on an individual chip. This has resulted in the emerging trend of a new convergent system[1] Currently, there are three main approaches to achieving these convergent systems, namely the system-on-chip (SOC), system-in-package (SIP) and system on package (SOP). SOC seeks to integrate numerous system functions on one silicon chip. However, this approach has numerous fundamental and economical limitations which include high fabrication costs and integration limits on wireless communications, which due to inherent losses of silicon and size restriction. SIP is a 3-D packaging approach, where vertical stacking of multi-chip modules is employed. Since all of the ICs in the stack are still limited to CMOS IC processing, the fundamental integration limitation of the SOC still remains. SOP on the other hand, seeks to achieve a highly integrated microminiaturized system on the package using silicon for transistor integration and package for RF, digital and optical integration[1] IC packaging is one of the key enabling technologies for microprocessor performance. As performance increases, technical challenges increase in the areas of power delivery, heat removal, I/O density and thermo-mechanical reliability. These are the most difficult challenges for improving performance and increasing integration, along with decreasing manufacturing cost. Chip-to-package interconnections in microsystems packages serve as electrical interconnections but often fail by mechanisms such as fatigue and creep. Furthermore, driven by the need for increase the system functionality and decrease the feature size, the International Technology Roadmap for Semi-conductors (ITRS) has predicted that integrated chip (IC) packages will have interconnections with I/O pitch of 90 nm by the year 2018 [2]. Lead-based solder materials have been used for interconnections in flip chip technology and the surface mount technology for many decades. The traditional lead-based and lead-free solder bumps will not satisfy the thermal mechanical requirement of these fine pitches interconnects. These electronic packages, even under normal operating conditions, can reach a temperature as high as 150C. Due to differences in the coefficient of thermal expansion of the materials in an IC package, the packages will experience significant thermal strains due to the mismatch, which in turn will cause lead and lead-free solder interconnections to fail prematurely. Aggarwal et al [3] had modeled the stress experienced by chip to package interconnect. In his work, he developed interconnects with a height of 15 to 50 micrometre on different substrate using classic beam theory. Figure 1 shows the schematic of his model and a summary of some of his results. Although compliant intrerconect could reduces the stress experienced by the interconnect, it is still in sufficient. Chng et al. [4] performed a parametric study on the fatigue life of a solder column for a pitch of 100micrometre using a macro-micro approach. In her work, she developed models of a solder column/bump with a pad size of 50micrometre and heights of 50 micrometre to 200 micrometre. Table I shows a summary of some of her results. Table 1.1: Fatigue life estimation of solder column chip thickness (micrometre) 250 640 640 640 board CTE (ppm/K) 18 18 10 5 solder column height (micrometre) Fatigue life estimation/cycle) 50 81 N.A 171 3237 100 150 27 276 3124 150 134 31 518 4405 200 74 38 273 5772 It can be seen from Table 1.1 that the fatigue lives of all solder columns are extremely short. Apart from the 5ppm/K board where there is excellent CTE matching, the largest fatigue life of the solder column is only about 518 cycles. As expected, the fatigue life increases significantly when the board CTE decreases from 18ppm/K to 10ppm/K and as the height increases from 50micrometre to 200micrometre.This is mainly due to the large strain induced by the thermal mismatch as shown in Figure 1.2. The maximum inelastic principal strain was about 0.16 which exceeds the maximum strain that the material can support. Although the fatigue life of the chip to package interconnection can be increases by increasing the interconnects height, it will not be able to meet the high frequency electrical requirements of the future IC where they need to be operating at a high frequencies of 10-20 GHz and a signal bandwidth of 20 Gbps, By definition, nanocrystalline materials are materials that have grain size less than 100nm and these materials are not new since nanocrystalline materials have been observed in several naturally-occurring specimens including seashells, bone, and tooth enamel [5, 6]. However, the nanocrystalline materials have been attracting a lot of research interest due to its superior mechanical and electrical properties as compared to the coarse-grained counterpart. For example, the nano-crystalline copper has about 6 times the strength of bulk copper [7]. Furthermore, the improvement in the mechanical properties due to the reduction in grain size has been well-documented. Increase in strength due to the reduction in grain-size is predicted by the Hall-Petch relationship which has also been confirmed numerically by Swygenhoven et al [8] and was first demonstrated experimentally by Weertman [9]. The implantation of nanocrystalline copper as interconnect materials seems to be feasible from the processing viewpoint too. Copper has been used as interconnects materials since 1989 whereas nano-copper has also been widely processed using electroplating and other severe plastic deformation techniques in the past few years. For instance, Lu et al. [10] have reported electroplating of nano-copper with grain size less than 100 nm and electrical conductivity comparable to microcrystalline copper. Furthermore, Aggarwal et al [11] have demonstrated the feasibility of using electrolytic plating processes to deposit nanocrystalline nickel as a back-end wafer compatible process. However, there are certain challenges regarding implantation of nanocrystalline copper as interconnects materials. As discussed above, nanocrystalline copper have a high potential of being used as the next generation interconnect for electronic packaging. However, it is vital to understand their material properties, deformation mechanisms and microstructures stability. Although the increase in strength due to the Hall-Petch relationship which has also been confirmed numerically and experimentally by Weertman [9], the improvement in the fatigue properties is not well documented and no model has been established to predict/characterize these nano materials in interconnection application; conflicting results regarding the fatigue properties have also been reported. Kumar et al [12] reported that for nano-crystalline and ultra-fine crystalline Ni, although there is an increase in tensile stress range and the endurance limit, the crack growth rate also increases. However, Bansal et al. [7] reported that with decreasing grain size, the tensile stress range increases but the crack growth rate decreases substantially at the same cyclic stress intensity range. Thus, nanostructured materials can potentially provide a solution for the reliability of low pitch interconnections. However, the fatigue resistance of nanostructured interconnections needs to be further investigated. Since grain boundaries in polycrystalline material increases the total energy of the system as compare to perfect single crystal, it will resulted in a driving force to reduce the overall grain boundary area by increasing the average grain size. In the case of nanocrystalline materials which have a high volume fraction of grain boundaries, there is a huge driving force for grain to growth and this presented a presents a significant obstacle to the processing and use of nanocrystalline copper for interconnect applications. Millet et al [13] have shown, though a series of systematic molecular dynamics simulations, grain growth in bulk nanocrystalline copper during annealing at constant temperature of 800K can be impeded with dopants segregated in the grain boundaries regions. However, it has been observed that stress can trigger grain growth in nanocrystalline materials [14] and there is no literature available on impeding stress assisted grain growth. There is an impending need to investigate the impediment to grain growth caused by the dopant during fatigue/stress assisted grain growth Dissertation Objectives The goal of present project is to develop a model for the fatigue resistance of nano-materials that have been shown to have superior fatigue resistance. Accordingly, the following research objectives are proposed. Develops a model for predicting fatigue life of nanostructured chip-to-package copper interconnections Develops a fundamental understanding on the fatigue behavior of nanocrystalline copper for interconnect application Addresses the issue on the stability of nanocrystalline materials undergoing cyclic loading Overview of the Thesis The thesis is organized so that past research on nanocrystalline materials forms the basis of the understanding and new knowledge discovered in this research. Chapter 2 reviews much of the pertinent literature regarding nanocrystalline materials, including synthesis, deformation mechanisms, and grain growth. Chapter 3 describes a detailed overview of the technical aspects of the molecular dynamics simulation method including inter-atomic potentials, time integration algorithms, the NVT NPT, and NEPT ensembles, as well as periodic boundary conditions and neighbor lists. Include in this chapter is the algorithms for creating nanocrystalline materials used in this dissertations.. Chapter 4 describes the simulation procedure designed to investigate and develop the long crack growth analysis. The results of the long crack growth analysis will be presented at the end of Chapter 4. Chapter 5 presents the result and discussion on mechanical behavior of single and nanocrystalline copper subjected to monotonic and cyclic loading whereas Chapter 6 presents the result and discussion on the impediment to grain growth caused by the dopant during fatigue/stress assisted grain growth. Finally, conclusions and recommendations for future work are presented in Chapter 5. Chapter 2 This chapter offers an expanded summary of the literature published with regards to the fabrication methods, characterization, and properties of nanocrystalline materials in addition to a description of existing interconnect technology. 2.1 Off-Chip Interconnect Technologies Chip-to-package interconnections in microsystems packages serve as electrical interconnections but they will often failed by mechanisms such as fatigue and creep. Furthermore, driven by the need for increase the system functionality and decrease the feature size, the International Technology Roadmap for Semi-conductors (ITRS) has predicted that interconnections of integrated chip (IC) packages will have a I/O pitch of 90 nm by the year 2018 [2]. The International Technology Roadmap for Semiconductors (ITRS) roadmap is a roadmap that semiconductor industry closely follows closely and its projects the need for several technology generations. The package must be capable of meeting these projections in order for it to be successful. This section reviews some of the current interconnect technology. Wire bonding [15] as shown in Figure 2.1, is generally considered as one of the most simple, cost-effective and flexible interconnect technology. The devices on the silicon die are (gold or aluminum) wire bonded to electrically connect from the chip to the wire bond pads on the periphery. However, the disadvantages of wire bonding are the slow rate, large pitch and long interconnect length and hence this will not be suitable for high I/O application. Instead of wires in the wire bonding, tape automated bonding (TAB) is an interconnect technology using a prefabricated perforated polyimide film, with copper leads between chip and substrate. The advantage of this technology is the high throughput and the high lead count. However, it is limited by the high initial costs for tooling. An alternative to peripheral interconnect technology is the area-array solution, as shown in Figure 2.3, that access the unused area by using the area under the chip. In area-array packaging, the chip has an array of solder bumps that are joined to a substrate. Under-fill is then fills the gap between the chip and substrate to enhance mechanical adhesion. This technology gives the highest packaging density methods and best electrical characteristics of all the avaiable interconnection technology. However, not only is its initial cost is high, it requires a very demanding technology to establish and operate. With the need for higher I/O density, compliant interconnects have been developed to satisfy the mechanical requirements of high performance micron sized interconnects. The basic idea is to reduce shear stress experienced by the interconnects through increasing their height or decreasing of its shear modulus (i.e. increases in their compliant) and hence the name compliant interconnects. Some of recent research in compliant interconnects include Tesseras Wide Area Vertical Expansion, Form Factors Wire on Wafer and Georgia Institute of Technologys Helix interconnects [17-19] as shown in Figure 2.4. Although compliant interconnects can solve the problem of mechanical reliability issue, they are done at the expense of the electrical performance. Since there is a need to reduce the packages parasitic through a decrease line delays, there is a need to minimize the electrical connection length in order to increase the system working frequency. Hence, compliant interconnect may not meet the high electrical frequency requirements of future devices. Figure 2.4: (a) Wide Area Vertical Expansion, (b) Wire on Wafer and (c) G-Helix [17-19] Lead and lead-free solders typically fail mechanical when scaled down to less than to a pitch of 100 mm. Compliant interconnections, on the other hand, do not meet the high frequency electrical requirements. The Microsystems Packaging Research Center at Georgia institute of Technology had demonstrated the feasibility of using re-workable nanostructure interconnections. Aggarwal et al [20] had show that nanostructured nickel interconnections, through a Flip Chip test vehicle, was able to improve the mechanical reliability while maintaining the shortest electrical connection length. However, the main disadvantages of this method was the significant signal loss at high frequency signal of nanocrystalline nickel [21]. As discussed above, nanostructure interconnects technology is the most promising interconnect technology to best meet the stringent mechanical and electrical requirement of next generation devices. However, there is a need of an alternate materials and a sensible choice of materials in this case would be nanocrystalline copper for its high strength material with superior electrical conductivity. Hence, it would be beneficial to use nanocrystalline-copper as material for the nanostructure interconnects. Due to the tendency for the grain to grow, there is a need to stabilize the grain growth in nanocrystalline copper before using it could be considered as a potential candidate for nanostructure interconnect. 2.2 Nanocrystalline material Nanocrystalline materials are polycrystalline materials with an average grain size of less than 100 nm [22]. Over the past decade , new nanocrystalline or nanostructured materials with key microstructural length scales on the order of a few tens of nanometers has been gaining a lot of interest in the material science research society. This is mainly due to its unique and superior properties, as compared to their microcrystalline counterparts which includes increased strength [22] and wear resistance [23]. These unique properties are due to the large volume fraction of atoms at or near the grain boundaries. As a result, these materials have unique properties that are representative of both the grain boundary surface characteristics and the bulk. Recent advances in synthesis and processing methodology for producing nanocrystalline materials such as inert gas condensation [24], mechanical milling [25, 26], electro-deposition [27], and severe plastic deformation [28] have made it possible to produce sufficient nanocrystalline materials for small scale application. 2.2.1 Synthesis Inert gas condensation, the first method used to synthesis bulk nanocrystalline [29], consists of evaporating a metal inside a high-vacuum chamber and then backfilling the chamber with inert gas [30]. These evaporated metal atoms would then collide with the gas atoms, causing them to lose kinetic energy and condenses into powder of small nano-crystals. These powders are then compacted under high pressure and vacuum into nearly fully dense nanocrystalline solids. The grain size distribution obtained from this method is usually very narrow. However, the major draws back of this method are its high porosity levels and imperfection bonding. Grain coarsening also occurs due to the high temperature during the compaction stage [31]. Mechanical milling consists of heavy cyclic deformation in powders until the final composition of the powders corresponds to a certain percentages of the respective initial constituents [25, 26]. A wide grain size distribution is obtained by this method. This technique is a popular method to prepare nanocrystalline materials because of its applicability to any material and simplicity. However, their main drawback includes contamination and grain coarsening during the consolidation stage. Electro-deposition consists of using electrical current to reduce cations of a desired material from a electrolyte solution and coating a conductive object on the substrate. Electro-deposition has many advantages over processing techniques and this includes its applicability to a wide variety of materials, low initial capital investment requirements and porosity-free finished products without a need for consolidation processing [27]. Furthermore, Shen et al. [32] and Lu et al.[33] had recently show that the right electro-deposition condition can produce a highly twinned structure which leads to enhanced ductility. The main drawback of this method is it is the difficulty to achieve high purity. Severe plastic deformation, such as high-pressure torsion, equal channel angular extrusion (ECAE), continuous confined shear straining and accumulative roll-bonding, uses extreme plastic straining to produce nanocrystalline materials by mechanisms such as grain fragmentation, dynamic recovery, and geometric re-crystallization [34]. It is the only technology that transformed conventional macro-grained metals directly into nanocrystalline materials without the need of potentially hazardous nano-sized powders. This is achieved by introducing very high shear deformations into the material under superimposed hydrostatic pressure. Two of the most commonly used methods are high-pressure torsion and ECAE [35]. In the study of the effect of ECAE on the microstructure of nanocrystalline copper, Dalla Torre et al [36] observed that the grains become more equi-axial and randomly orientation as the number of passes increases, as shown in Figure 2.5 Figure 2.5: Microstructure of ECAE copper subjected to (a) 1 passes (b) 2 passes (c) 4 passes (d) 8 passes (e) 12 passes and (f) 16 passes [36] 2.2.2 Mechanical Behavior of nanocrystalline materials Due to the small grain size and high volume fraction of grain boundaries, nanocrystalline materials exhibit significantly different properties and behavior as compared to their microcrystalline counterpart. The structure and mechanical behavior of nanocrystalline materials has been the subject of a lot of researchers interests both experimentally [37-43] and theoretically [44-50]. This section reviews the principal mechanical properties and behavior of nanocrystalline materials. 2.2.2.1 Strength and ductility Recent studies of nanocrystalline metals have shown that there is a five to ten fold increases in the strength and hardness as compared to their microcrystalline state [7, 36, 37, 51, 52]. This increase in the strength is due to the presence of grain boundaries impeding the nucleation and movement of dislocations. Since decreasing grain boundary size increases the number of barrier and the amount of applied stress necessary to move a dislocation across a grain boundary, this resulted in a much higher yield strength. The inverse relationship between grain size and strength is characterized by the Hall-Petch relationship [53, 54] as shown in equation (2.1). Eq (2.1) In equation (2.1), s is the mechanical strength, k is a material constant and d is the average grain size. Hence, nanocrystalline materials are expected to exhibit higher strength as compared to their microcrystalline counterpart. Figure 2.6 and Figure 2.7 show the summary of hardness and yield strength from tensile test that are reported in the literature. Indeed, hardness and yield strength of copper with a grain size of 10nm (3GPa) can be one order higher than their microcrystalline counterpart. To the larger specimens. Derivation from Hall-Petch relationship begins as the grain size approaches 30nm where the stresses needed to activate the dislocation multiplication via Frank-Read sources within the grains are too high and the plastic deformation is instead accommodated by grain boundaries sliding and migration.[12]. Furthermore, as the grain size reduces, the volume fraction of the grain boundaries and the triple points increases. Material properties will be more representative of the grain boundary activity [64] and this will resulting the strength to be inversely proportional to grain size instead of square roots of the grain size as predicted by Hall Petch relation [65]. Further reduction in the grain size will result in grain boundaries processes controlling the plastic deformation and reverse Hall-Petch effect, where the materials soften, will take place. Although sample defects had been account for the earlier experimental observation of reverse Hall-Petch effect[24], Swygenhoven et al [66] and Schiotz et al [47], using molecular simulation, was able to showed that nanocrystalline copper had the highest strength (about 2.3GPa ) at a grain size of 8nm and 10-15nm respectively. Conrad et al [67] pointed out that below this critical grain size, the mechanisms shifted to grain boundary-mediated from dislocation-mediated plasticity and this causes the material to become dependent on strain rate, temperature, Taylor orientation factor and presence of the type of dislocation. The yield stress of nanocrystalline copper was highly sensitive to strain rate even though it is a fcc materials. The strain rate sensitivity, m, in equation 2.2 a engineering parameter which measured the dependency of the strain rate and Figure 2.8 shows a summary of m as a function of grain size for copper specimen in the literature [51, 68-70]. Due to high localized dislocation activities at the grain boundaries which results in enhanced strain rate sensitivities in nanocrystalline materials, m increases drastically when the grain size is below 0.1 mm as shown in Figure 2.8. (2.2) Room temperature strain rate sensitivity was found to dependent on dislocation activities and grain boundaries diffusion [52, 71, 72]. Due to the negligible lattice diffusion at room temperature, the rate limiting process for microcrystalline copper was the gliding dislocation to cutting through forest dislocation, resulting in low strain rate sensitivities. However, due to the increasing presence of obstacles such as grain boundaries for nanocrystalline materials, the rate limiting process for smaller grain size was the interaction of dislocation and the grain boundaries, which is strain rate and temperature dependence. By considering the length scale of the dislocation and grain boundaries interaction, Cheng et al [52] proposed the following model for strain rate sensitivities . (2.3) z is the distance swept by the dislocation during activation, r is the dislocation density and a, a and b are the proportional factors. With this model, they will be able to predict higher strain rate sensitivities for nanocrystalline material produced by severe plastic deformation as compared to other technique. Since the twin boundaries in nanocrystalline or ultra fine grain copper served as a barriers for dislocation motion and nucleation which led to highly localized dislocations near the twin boundaries, the strain rate sensitivity of copper with high density of coherent twin boundaries was found to be higher than those without any twin boundaries [33]. Lastly, the increase enhanced strain rate sensitivity in nanocrystalline copper had been credited for it increases in strength and ductility. For example, Valiev et al [60] credited the enhanced strain rate sensitivity of 0.16 for the high ductility. In addition to a strong dependency on the strain rate, strength in nanocrystalline materials was also highly dependent on the temperature. Wang et al [73] observed that the yield strength for ultra fine grain copper with a grain size of 300nm increases from approximately 370MPa to 500MPa when the temperature reduces from room temperature to 77k. The authors attributed this increase in yield strength due to the absence of additional thermal deformation processes at 77k. This is consistent with Huang et al [74] observation where the temperature dependence of nanocrystalline copper with an increase in hardness of nanocrystalline copper with lowering the temperature is noted Ductility is another important characteristic of nanocrystalline materials. In microcrystalline materials, a reduction in grain size will increase the ductility due to the presence of grain boundaries acting as effective barriers to the propagation of micro-cracks[75]. However, nanocrystalline copper showed a lower strain to failure than that of their microcrystalline counterparts and this lacks in ductility was attributed to the presence of processing defects [76]. Recent advanced in processing of nanocrystalline materials offer materials with fairly good ductility in additional to ultra-high strength. Lu et al [10] reported that nanocrystalline copper with minimal flaw produced via electro-deposition had an elongation to fracture of 30%. Furthermore, Youssef et al [77] observed a 15.5% elongation to failure for defect free nanocrystalline copper produced via mechanical milling. Hence, it was possible for nanocrystalline copper to be both strong and ductile if the processing artifacts are minimized. The failure are usually consists of dimples several time larger than their grain size was normally found on the failure morphology of nanocrystalline materials and Kumar et al [78] presented the following model for initiation and hence the eventual failure of nanocrystalline materials. Furthermore, the presence of shear region was found to be due to shear localization since the ratio of strain hardening rate to prevailing stress was usually small [79, 80]. Figure 2.9: Schematic illustration of fracture in nanocrystalline material postulated by Kumar et al [78] 2.2.2.2 Creeps Nanocrystalline materials are expected to creep during room temperature. This is because Due to the higher fraction of grain boundaries and triple junctions, self diffusivity of nanocrystalline material had been shown to increase by an order of three as compared to microcrystalline copper [81]. Since creep behavior was dependent on grain size and diffusivity, with creep rate increases with an increase in diffusivity or a decrease in grain size, the creep temperature for nanocrystalline copper was known to be a small fraction of melting temperature (about 0.22 of its melting points). Furthermore, since creep had always been cited as one of the reason for grain size softening in nanocrystalline materials, creeps were other important mechanical properties of nanocrystalline materials that had been gaining a lot of researchers attention. Due to the high volume fraction of grain boundaries and enhanced diffusivity rate Model for Predicting Fatigue Life of Nanomaterials Model for Predicting Fatigue Life of Nanomaterials Introduction In the past, the primary function of micro-systems packaging was to provide input/output (I/O) connections to and from integrated circuits (ICs) and to provide interconnection between the components on the system board level while physically supporting the electronic device and protecting the assembly from the environment. In order to increase the functionality and the miniaturization of the current electronic devices, these IC devices have not only incorporated more transistors but have also included more active and passive components on an individual chip. This has resulted in the emerging trend of a new convergent system[1] Currently, there are three main approaches to achieving these convergent systems, namely the system-on-chip (SOC), system-in-package (SIP) and system on package (SOP). SOC seeks to integrate numerous system functions on one silicon chip. However, this approach has numerous fundamental and economical limitations which include high fabrication costs and integration limits on wireless communications, which due to inherent losses of silicon and size restriction. SIP is a 3-D packaging approach, where vertical stacking of multi-chip modules is employed. Since all of the ICs in the stack are still limited to CMOS IC processing, the fundamental integration limitation of the SOC still remains. SOP on the other hand, seeks to achieve a highly integrated microminiaturized system on the package using silicon for transistor integration and package for RF, digital and optical integration[1] IC packaging is one of the key enabling technologies for microprocessor performance. As performance increases, technical challenges increase in the areas of power delivery, heat removal, I/O density and thermo-mechanical reliability. These are the most difficult challenges for improving performance and increasing integration, along with decreasing manufacturing cost. Chip-to-package interconnections in microsystems packages serve as electrical interconnections but often fail by mechanisms such as fatigue and creep. Furthermore, driven by the need for increase the system functionality and decrease the feature size, the International Technology Roadmap for Semi-conductors (ITRS) has predicted that integrated chip (IC) packages will have interconnections with I/O pitch of 90 nm by the year 2018 [2]. Lead-based solder materials have been used for interconnections in flip chip technology and the surface mount technology for many decades. The traditional lead-based and lead-free solder bumps will not satisfy the thermal mechanical requirement of these fine pitches interconnects. These electronic packages, even under normal operating conditions, can reach a temperature as high as 150C. Due to differences in the coefficient of thermal expansion of the materials in an IC package, the packages will experience significant thermal strains due to the mismatch, which in turn will cause lead and lead-free solder interconnections to fail prematurely. Aggarwal et al [3] had modeled the stress experienced by chip to package interconnect. In his work, he developed interconnects with a height of 15 to 50 micrometre on different substrate using classic beam theory. Figure 1 shows the schematic of his model and a summary of some of his results. Although compliant intrerconect could reduces the stress experienced by the interconnect, it is still in sufficient. Chng et al. [4] performed a parametric study on the fatigue life of a solder column for a pitch of 100micrometre using a macro-micro approach. In her work, she developed models of a solder column/bump with a pad size of 50micrometre and heights of 50 micrometre to 200 micrometre. Table I shows a summary of some of her results. Table 1.1: Fatigue life estimation of solder column chip thickness (micrometre) 250 640 640 640 board CTE (ppm/K) 18 18 10 5 solder column height (micrometre) Fatigue life estimation/cycle) 50 81 N.A 171 3237 100 150 27 276 3124 150 134 31 518 4405 200 74 38 273 5772 It can be seen from Table 1.1 that the fatigue lives of all solder columns are extremely short. Apart from the 5ppm/K board where there is excellent CTE matching, the largest fatigue life of the solder column is only about 518 cycles. As expected, the fatigue life increases significantly when the board CTE decreases from 18ppm/K to 10ppm/K and as the height increases from 50micrometre to 200micrometre.This is mainly due to the large strain induced by the thermal mismatch as shown in Figure 1.2. The maximum inelastic principal strain was about 0.16 which exceeds the maximum strain that the material can support. Although the fatigue life of the chip to package interconnection can be increases by increasing the interconnects height, it will not be able to meet the high frequency electrical requirements of the future IC where they need to be operating at a high frequencies of 10-20 GHz and a signal bandwidth of 20 Gbps, By definition, nanocrystalline materials are materials that have grain size less than 100nm and these materials are not new since nanocrystalline materials have been observed in several naturally-occurring specimens including seashells, bone, and tooth enamel [5, 6]. However, the nanocrystalline materials have been attracting a lot of research interest due to its superior mechanical and electrical properties as compared to the coarse-grained counterpart. For example, the nano-crystalline copper has about 6 times the strength of bulk copper [7]. Furthermore, the improvement in the mechanical properties due to the reduction in grain size has been well-documented. Increase in strength due to the reduction in grain-size is predicted by the Hall-Petch relationship which has also been confirmed numerically by Swygenhoven et al [8] and was first demonstrated experimentally by Weertman [9]. The implantation of nanocrystalline copper as interconnect materials seems to be feasible from the processing viewpoint too. Copper has been used as interconnects materials since 1989 whereas nano-copper has also been widely processed using electroplating and other severe plastic deformation techniques in the past few years. For instance, Lu et al. [10] have reported electroplating of nano-copper with grain size less than 100 nm and electrical conductivity comparable to microcrystalline copper. Furthermore, Aggarwal et al [11] have demonstrated the feasibility of using electrolytic plating processes to deposit nanocrystalline nickel as a back-end wafer compatible process. However, there are certain challenges regarding implantation of nanocrystalline copper as interconnects materials. As discussed above, nanocrystalline copper have a high potential of being used as the next generation interconnect for electronic packaging. However, it is vital to understand their material properties, deformation mechanisms and microstructures stability. Although the increase in strength due to the Hall-Petch relationship which has also been confirmed numerically and experimentally by Weertman [9], the improvement in the fatigue properties is not well documented and no model has been established to predict/characterize these nano materials in interconnection application; conflicting results regarding the fatigue properties have also been reported. Kumar et al [12] reported that for nano-crystalline and ultra-fine crystalline Ni, although there is an increase in tensile stress range and the endurance limit, the crack growth rate also increases. However, Bansal et al. [7] reported that with decreasing grain size, the tensile stress range increases but the crack growth rate decreases substantially at the same cyclic stress intensity range. Thus, nanostructured materials can potentially provide a solution for the reliability of low pitch interconnections. However, the fatigue resistance of nanostructured interconnections needs to be further investigated. Since grain boundaries in polycrystalline material increases the total energy of the system as compare to perfect single crystal, it will resulted in a driving force to reduce the overall grain boundary area by increasing the average grain size. In the case of nanocrystalline materials which have a high volume fraction of grain boundaries, there is a huge driving force for grain to growth and this presented a presents a significant obstacle to the processing and use of nanocrystalline copper for interconnect applications. Millet et al [13] have shown, though a series of systematic molecular dynamics simulations, grain growth in bulk nanocrystalline copper during annealing at constant temperature of 800K can be impeded with dopants segregated in the grain boundaries regions. However, it has been observed that stress can trigger grain growth in nanocrystalline materials [14] and there is no literature available on impeding stress assisted grain growth. There is an impending need to investigate the impediment to grain growth caused by the dopant during fatigue/stress assisted grain growth Dissertation Objectives The goal of present project is to develop a model for the fatigue resistance of nano-materials that have been shown to have superior fatigue resistance. Accordingly, the following research objectives are proposed. Develops a model for predicting fatigue life of nanostructured chip-to-package copper interconnections Develops a fundamental understanding on the fatigue behavior of nanocrystalline copper for interconnect application Addresses the issue on the stability of nanocrystalline materials undergoing cyclic loading Overview of the Thesis The thesis is organized so that past research on nanocrystalline materials forms the basis of the understanding and new knowledge discovered in this research. Chapter 2 reviews much of the pertinent literature regarding nanocrystalline materials, including synthesis, deformation mechanisms, and grain growth. Chapter 3 describes a detailed overview of the technical aspects of the molecular dynamics simulation method including inter-atomic potentials, time integration algorithms, the NVT NPT, and NEPT ensembles, as well as periodic boundary conditions and neighbor lists. Include in this chapter is the algorithms for creating nanocrystalline materials used in this dissertations.. Chapter 4 describes the simulation procedure designed to investigate and develop the long crack growth analysis. The results of the long crack growth analysis will be presented at the end of Chapter 4. Chapter 5 presents the result and discussion on mechanical behavior of single and nanocrystalline copper subjected to monotonic and cyclic loading whereas Chapter 6 presents the result and discussion on the impediment to grain growth caused by the dopant during fatigue/stress assisted grain growth. Finally, conclusions and recommendations for future work are presented in Chapter 5. Chapter 2 This chapter offers an expanded summary of the literature published with regards to the fabrication methods, characterization, and properties of nanocrystalline materials in addition to a description of existing interconnect technology. 2.1 Off-Chip Interconnect Technologies Chip-to-package interconnections in microsystems packages serve as electrical interconnections but they will often failed by mechanisms such as fatigue and creep. Furthermore, driven by the need for increase the system functionality and decrease the feature size, the International Technology Roadmap for Semi-conductors (ITRS) has predicted that interconnections of integrated chip (IC) packages will have a I/O pitch of 90 nm by the year 2018 [2]. The International Technology Roadmap for Semiconductors (ITRS) roadmap is a roadmap that semiconductor industry closely follows closely and its projects the need for several technology generations. The package must be capable of meeting these projections in order for it to be successful. This section reviews some of the current interconnect technology. Wire bonding [15] as shown in Figure 2.1, is generally considered as one of the most simple, cost-effective and flexible interconnect technology. The devices on the silicon die are (gold or aluminum) wire bonded to electrically connect from the chip to the wire bond pads on the periphery. However, the disadvantages of wire bonding are the slow rate, large pitch and long interconnect length and hence this will not be suitable for high I/O application. Instead of wires in the wire bonding, tape automated bonding (TAB) is an interconnect technology using a prefabricated perforated polyimide film, with copper leads between chip and substrate. The advantage of this technology is the high throughput and the high lead count. However, it is limited by the high initial costs for tooling. An alternative to peripheral interconnect technology is the area-array solution, as shown in Figure 2.3, that access the unused area by using the area under the chip. In area-array packaging, the chip has an array of solder bumps that are joined to a substrate. Under-fill is then fills the gap between the chip and substrate to enhance mechanical adhesion. This technology gives the highest packaging density methods and best electrical characteristics of all the avaiable interconnection technology. However, not only is its initial cost is high, it requires a very demanding technology to establish and operate. With the need for higher I/O density, compliant interconnects have been developed to satisfy the mechanical requirements of high performance micron sized interconnects. The basic idea is to reduce shear stress experienced by the interconnects through increasing their height or decreasing of its shear modulus (i.e. increases in their compliant) and hence the name compliant interconnects. Some of recent research in compliant interconnects include Tesseras Wide Area Vertical Expansion, Form Factors Wire on Wafer and Georgia Institute of Technologys Helix interconnects [17-19] as shown in Figure 2.4. Although compliant interconnects can solve the problem of mechanical reliability issue, they are done at the expense of the electrical performance. Since there is a need to reduce the packages parasitic through a decrease line delays, there is a need to minimize the electrical connection length in order to increase the system working frequency. Hence, compliant interconnect may not meet the high electrical frequency requirements of future devices. Figure 2.4: (a) Wide Area Vertical Expansion, (b) Wire on Wafer and (c) G-Helix [17-19] Lead and lead-free solders typically fail mechanical when scaled down to less than to a pitch of 100 mm. Compliant interconnections, on the other hand, do not meet the high frequency electrical requirements. The Microsystems Packaging Research Center at Georgia institute of Technology had demonstrated the feasibility of using re-workable nanostructure interconnections. Aggarwal et al [20] had show that nanostructured nickel interconnections, through a Flip Chip test vehicle, was able to improve the mechanical reliability while maintaining the shortest electrical connection length. However, the main disadvantages of this method was the significant signal loss at high frequency signal of nanocrystalline nickel [21]. As discussed above, nanostructure interconnects technology is the most promising interconnect technology to best meet the stringent mechanical and electrical requirement of next generation devices. However, there is a need of an alternate materials and a sensible choice of materials in this case would be nanocrystalline copper for its high strength material with superior electrical conductivity. Hence, it would be beneficial to use nanocrystalline-copper as material for the nanostructure interconnects. Due to the tendency for the grain to grow, there is a need to stabilize the grain growth in nanocrystalline copper before using it could be considered as a potential candidate for nanostructure interconnect. 2.2 Nanocrystalline material Nanocrystalline materials are polycrystalline materials with an average grain size of less than 100 nm [22]. Over the past decade , new nanocrystalline or nanostructured materials with key microstructural length scales on the order of a few tens of nanometers has been gaining a lot of interest in the material science research society. This is mainly due to its unique and superior properties, as compared to their microcrystalline counterparts which includes increased strength [22] and wear resistance [23]. These unique properties are due to the large volume fraction of atoms at or near the grain boundaries. As a result, these materials have unique properties that are representative of both the grain boundary surface characteristics and the bulk. Recent advances in synthesis and processing methodology for producing nanocrystalline materials such as inert gas condensation [24], mechanical milling [25, 26], electro-deposition [27], and severe plastic deformation [28] have made it possible to produce sufficient nanocrystalline materials for small scale application. 2.2.1 Synthesis Inert gas condensation, the first method used to synthesis bulk nanocrystalline [29], consists of evaporating a metal inside a high-vacuum chamber and then backfilling the chamber with inert gas [30]. These evaporated metal atoms would then collide with the gas atoms, causing them to lose kinetic energy and condenses into powder of small nano-crystals. These powders are then compacted under high pressure and vacuum into nearly fully dense nanocrystalline solids. The grain size distribution obtained from this method is usually very narrow. However, the major draws back of this method are its high porosity levels and imperfection bonding. Grain coarsening also occurs due to the high temperature during the compaction stage [31]. Mechanical milling consists of heavy cyclic deformation in powders until the final composition of the powders corresponds to a certain percentages of the respective initial constituents [25, 26]. A wide grain size distribution is obtained by this method. This technique is a popular method to prepare nanocrystalline materials because of its applicability to any material and simplicity. However, their main drawback includes contamination and grain coarsening during the consolidation stage. Electro-deposition consists of using electrical current to reduce cations of a desired material from a electrolyte solution and coating a conductive object on the substrate. Electro-deposition has many advantages over processing techniques and this includes its applicability to a wide variety of materials, low initial capital investment requirements and porosity-free finished products without a need for consolidation processing [27]. Furthermore, Shen et al. [32] and Lu et al.[33] had recently show that the right electro-deposition condition can produce a highly twinned structure which leads to enhanced ductility. The main drawback of this method is it is the difficulty to achieve high purity. Severe plastic deformation, such as high-pressure torsion, equal channel angular extrusion (ECAE), continuous confined shear straining and accumulative roll-bonding, uses extreme plastic straining to produce nanocrystalline materials by mechanisms such as grain fragmentation, dynamic recovery, and geometric re-crystallization [34]. It is the only technology that transformed conventional macro-grained metals directly into nanocrystalline materials without the need of potentially hazardous nano-sized powders. This is achieved by introducing very high shear deformations into the material under superimposed hydrostatic pressure. Two of the most commonly used methods are high-pressure torsion and ECAE [35]. In the study of the effect of ECAE on the microstructure of nanocrystalline copper, Dalla Torre et al [36] observed that the grains become more equi-axial and randomly orientation as the number of passes increases, as shown in Figure 2.5 Figure 2.5: Microstructure of ECAE copper subjected to (a) 1 passes (b) 2 passes (c) 4 passes (d) 8 passes (e) 12 passes and (f) 16 passes [36] 2.2.2 Mechanical Behavior of nanocrystalline materials Due to the small grain size and high volume fraction of grain boundaries, nanocrystalline materials exhibit significantly different properties and behavior as compared to their microcrystalline counterpart. The structure and mechanical behavior of nanocrystalline materials has been the subject of a lot of researchers interests both experimentally [37-43] and theoretically [44-50]. This section reviews the principal mechanical properties and behavior of nanocrystalline materials. 2.2.2.1 Strength and ductility Recent studies of nanocrystalline metals have shown that there is a five to ten fold increases in the strength and hardness as compared to their microcrystalline state [7, 36, 37, 51, 52]. This increase in the strength is due to the presence of grain boundaries impeding the nucleation and movement of dislocations. Since decreasing grain boundary size increases the number of barrier and the amount of applied stress necessary to move a dislocation across a grain boundary, this resulted in a much higher yield strength. The inverse relationship between grain size and strength is characterized by the Hall-Petch relationship [53, 54] as shown in equation (2.1). Eq (2.1) In equation (2.1), s is the mechanical strength, k is a material constant and d is the average grain size. Hence, nanocrystalline materials are expected to exhibit higher strength as compared to their microcrystalline counterpart. Figure 2.6 and Figure 2.7 show the summary of hardness and yield strength from tensile test that are reported in the literature. Indeed, hardness and yield strength of copper with a grain size of 10nm (3GPa) can be one order higher than their microcrystalline counterpart. To the larger specimens. Derivation from Hall-Petch relationship begins as the grain size approaches 30nm where the stresses needed to activate the dislocation multiplication via Frank-Read sources within the grains are too high and the plastic deformation is instead accommodated by grain boundaries sliding and migration.[12]. Furthermore, as the grain size reduces, the volume fraction of the grain boundaries and the triple points increases. Material properties will be more representative of the grain boundary activity [64] and this will resulting the strength to be inversely proportional to grain size instead of square roots of the grain size as predicted by Hall Petch relation [65]. Further reduction in the grain size will result in grain boundaries processes controlling the plastic deformation and reverse Hall-Petch effect, where the materials soften, will take place. Although sample defects had been account for the earlier experimental observation of reverse Hall-Petch effect[24], Swygenhoven et al [66] and Schiotz et al [47], using molecular simulation, was able to showed that nanocrystalline copper had the highest strength (about 2.3GPa ) at a grain size of 8nm and 10-15nm respectively. Conrad et al [67] pointed out that below this critical grain size, the mechanisms shifted to grain boundary-mediated from dislocation-mediated plasticity and this causes the material to become dependent on strain rate, temperature, Taylor orientation factor and presence of the type of dislocation. The yield stress of nanocrystalline copper was highly sensitive to strain rate even though it is a fcc materials. The strain rate sensitivity, m, in equation 2.2 a engineering parameter which measured the dependency of the strain rate and Figure 2.8 shows a summary of m as a function of grain size for copper specimen in the literature [51, 68-70]. Due to high localized dislocation activities at the grain boundaries which results in enhanced strain rate sensitivities in nanocrystalline materials, m increases drastically when the grain size is below 0.1 mm as shown in Figure 2.8. (2.2) Room temperature strain rate sensitivity was found to dependent on dislocation activities and grain boundaries diffusion [52, 71, 72]. Due to the negligible lattice diffusion at room temperature, the rate limiting process for microcrystalline copper was the gliding dislocation to cutting through forest dislocation, resulting in low strain rate sensitivities. However, due to the increasing presence of obstacles such as grain boundaries for nanocrystalline materials, the rate limiting process for smaller grain size was the interaction of dislocation and the grain boundaries, which is strain rate and temperature dependence. By considering the length scale of the dislocation and grain boundaries interaction, Cheng et al [52] proposed the following model for strain rate sensitivities . (2.3) z is the distance swept by the dislocation during activation, r is the dislocation density and a, a and b are the proportional factors. With this model, they will be able to predict higher strain rate sensitivities for nanocrystalline material produced by severe plastic deformation as compared to other technique. Since the twin boundaries in nanocrystalline or ultra fine grain copper served as a barriers for dislocation motion and nucleation which led to highly localized dislocations near the twin boundaries, the strain rate sensitivity of copper with high density of coherent twin boundaries was found to be higher than those without any twin boundaries [33]. Lastly, the increase enhanced strain rate sensitivity in nanocrystalline copper had been credited for it increases in strength and ductility. For example, Valiev et al [60] credited the enhanced strain rate sensitivity of 0.16 for the high ductility. In addition to a strong dependency on the strain rate, strength in nanocrystalline materials was also highly dependent on the temperature. Wang et al [73] observed that the yield strength for ultra fine grain copper with a grain size of 300nm increases from approximately 370MPa to 500MPa when the temperature reduces from room temperature to 77k. The authors attributed this increase in yield strength due to the absence of additional thermal deformation processes at 77k. This is consistent with Huang et al [74] observation where the temperature dependence of nanocrystalline copper with an increase in hardness of nanocrystalline copper with lowering the temperature is noted Ductility is another important characteristic of nanocrystalline materials. In microcrystalline materials, a reduction in grain size will increase the ductility due to the presence of grain boundaries acting as effective barriers to the propagation of micro-cracks[75]. However, nanocrystalline copper showed a lower strain to failure than that of their microcrystalline counterparts and this lacks in ductility was attributed to the presence of processing defects [76]. Recent advanced in processing of nanocrystalline materials offer materials with fairly good ductility in additional to ultra-high strength. Lu et al [10] reported that nanocrystalline copper with minimal flaw produced via electro-deposition had an elongation to fracture of 30%. Furthermore, Youssef et al [77] observed a 15.5% elongation to failure for defect free nanocrystalline copper produced via mechanical milling. Hence, it was possible for nanocrystalline copper to be both strong and ductile if the processing artifacts are minimized. The failure are usually consists of dimples several time larger than their grain size was normally found on the failure morphology of nanocrystalline materials and Kumar et al [78] presented the following model for initiation and hence the eventual failure of nanocrystalline materials. Furthermore, the presence of shear region was found to be due to shear localization since the ratio of strain hardening rate to prevailing stress was usually small [79, 80]. Figure 2.9: Schematic illustration of fracture in nanocrystalline material postulated by Kumar et al [78] 2.2.2.2 Creeps Nanocrystalline materials are expected to creep during room temperature. This is because Due to the higher fraction of grain boundaries and triple junctions, self diffusivity of nanocrystalline material had been shown to increase by an order of three as compared to microcrystalline copper [81]. Since creep behavior was dependent on grain size and diffusivity, with creep rate increases with an increase in diffusivity or a decrease in grain size, the creep temperature for nanocrystalline copper was known to be a small fraction of melting temperature (about 0.22 of its melting points). Furthermore, since creep had always been cited as one of the reason for grain size softening in nanocrystalline materials, creeps were other important mechanical properties of nanocrystalline materials that had been gaining a lot of researchers attention. Due to the high volume fraction of grain boundaries and enhanced diffusivity rate