As the world evolves to technology scaling, leakage power has become a problem where the fraction of leakage power continues to intensify because of reduced gate dielectric thickness and shortened channel lengths. In an attempt to achieve energy efficient, cheaper and faster computing, 3-D (three-dimensional) transistors which are promising replacements for 2-D or planar transistors are being proposed. Processor makers in their bid to reduce the planar Metal-Oxide-Semiconductor Field Effect Transistor (MOSFET) beyond 25nm from 250nm transistors encountered challenges in controlling the on-and-off flow of current in conventional chips since it is very difficult to turn off the transistor when it's very small. With the 3-D transistors, control of current in chips is made achievable.
According to Chenming (2012) the two structure concepts of 3-D transistors being considered today as an emerging technology and in response to a DARPA [the Defense Advanced Research Projects Agency] request for proposal for "Sub 25nm Switches" in 1996 are:
i. FinFET (Fin Field Effect Technology) and
ii. UTB-SOI (Ultrathin-body Silicon-on-Insulator)
BRIEF DESCRIPTIONS
FinFET (Fin Field Effect Technology)
FinFET is designed with a thin body shaped like a fish fin which can be constructed on Silicon-on-Insulator (SOI) substrate. The base is patterned much as a planar MOSFET. The fin is coated with gate stack - the gate and insulator - and lower than the gate thickness in order to suppress the short channel effects i.e. Gate Voltage, Vt become increasingly sensitive to device variation. The practical design of FINFET enables voltage on the gate to effectively stop the leak of charge across the transistor's channel which is a problem in conventional transistors. The FinFET design is chosen by Intel and is referred to as "tri-gate" transistor.
UTB-SOI (Ultrathin-body Silicon-on-Insulator)
University of Bedfordshire, United KingdomUTB-SOI is designed with a sandwich of Silicon substrate, glass and thin Silicon as top layer. The Silicon film is so thin i.e. a nanometers-thick that it allows the gate to better stanch any leaks. Intel competitors such as IBM and AMD may go with the ultrathin-body (UTB) design for their 22-nm chips.
SIGNIFICANCE OF 3-D TRANSISTORS
The tri-gate transistor will allow Intel to shrink the smallest features in its transistors from 32nm to 22 nanometers while cutting power consumption in half.
Making things small is crucial for making electronic devices faster, cheaper and power efficient for the consumers and the producers.
3-D transistors solve one of the main problems with conventional transistors i.e. the leak of charge across transistor's channel.
COMPARISON BETWEEN THE METHODS
Because UTBs rely on something that the semiconductor makers do not have to make, UTBs need less manufacturing and design development work than FinFETs.
UTB's thin silicon makes less current goes through, hence a lower speed.
ADVANTAGES OF FinFET OVER UTBs
UTB wafers are costlier to produce than FinFETs.
FinFET's versatility makes it a better option for high speed over UTBs.
FinFETs have ease of fabrication and compability with existing CMOS fabrication technology (Nowak et al. 2004)
TREND AND FUTURE OF EACH METHOD
By scaling body thickness with length of gate Lg, future opportunities for low power circuits with higher performance and better speed can be proposed with:
UTB-SOI - its prospect of easy ramp up and back-gating
FinFET - by multiplying fin height for better density and vacuum spacer.
CONCLUSION
FinFET and UTB-SOI both show a new scaling path forward and promise practical low voltage near-threshold circuits. The proposals of these two 3-D transistors will eliminate the challenges faced in the scaling of bulk MOSFETs beyond 32nm: severe short-channel effects, subthreshold leakage, gate-dielectric leakage, enhanced sensitivity to process variations. (Muttreja et al. 2007)
For future research, improving electrostatics in 3-D FinFET over UTBs should be examined.
References
Chenming Hu (2012) 'Physical and Failure Analysis of Integrated Circuits (IPFA)'. Proceedings of the 2012 19th IEEE International Symposium on the 3D FinFET and other sub-22nm transistors. Singapore, 2-6/7/12. IEEE. Available at: http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=6306337&tag=1. (Accessed: 27 November 2012).
Chenming Hu (2011) The Origins of Intel's New Transistor, and Its Future, [Proceedings of Q&A by Rachel Courtland]. 9 May. IEEE Spectrum [Online]. Available at: http://spectrum.ieee.org/semiconductors/design/the-origins-of-intels-new-transistor-and-its-future/1 (Accessed: 27 November 2012).
Freedman, David H (2012) 'Technology Review', 3-D Transistors, 116(3), pp.40. CSA Illumina [Online] Available at: http://md1.csa.com/partners/viewrecord.php (Accessed: 28 November 2012)
MUTTREJA, A., AGARWAL, N., AND JHA, N. K. 2007. CMOS logic design with independent-gate FinFETs. In Proceedings of the International Conference on Computer Design. 560-567.
NOWAK, E. J., ALLER, I., LUDWIG, T., KIM, K., JOSHI, R. V., AND CHUANG, C.-T. 2004. Turning silicon on its edge. IEEE Circ. Dev. Mag. 4, 20-31.
Radosavljevic, M.; Dewey, G.; Basu, D. et al (2011) 'Electron Devices Meeting (IEDM)'. Proceedings of the 2011 IEEE International Symposium on Electrostatics improvement in 3-D tri-gate over ultra-thin body planar InGaAs quantum well field effect transistors with high-K gate dielectric and scaled gate-to-drain/gate-to-source separation. Washington, DC, 5-7/12/11. IEEE. Available at: http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=6131661&tag=1. (Accessed: 28 November 2012).
Wei Z., Niraj K. and Li S. (2010) 'Emerging Technologies in Computing Systems', Low-power 3D nano/CMOS hybrid dynamically reconfigurable architecture, 6(3), pp.17-20. ACM [Online] Available at: http://0-dl.acm.org.brum.beds.ac.uk/citation.cfm?id=1777401.1777403&coll=DL&dl=ACM&CFID=215357008&CFTOKEN=63057394 (Accessed: 28 November 2012)
Survey of Facebook's Timeline
Oyediran Adeyemi Oyepeju
Student No.: 1119124
University of Bedfordshire, UK
Abstract-Facebook's Timeline is a product of Web 2.0 which is growing in artificial intelligence using complex combination of algorithms and metrics. In this study, we try to review the dynamics of Timeline, how it provides users with processed data streams, its advantages as well as disadvantages to the web community and where its future holds.
Keywords- Social Index; Facebook; Timeline; Google +1; Data Stream; Social Network; Microblog, Intelligent Search Engine, Collaborative Computing.
Introduction
Social Networking Technology reaches a new today and it is becoming relevant among a reasonable portion of the world's population. Friends and loved ones want to connect and share, businesses want to sell, organizations need an authentic and loyal customer base. Facebook, a social network site recently introduced a new method to interconnect these intentions and aspirations with minimal interference at the same time beneficial for advertisers and users. This method of social indexing is called the Facebook's Timeline.
The primary aim of the Facebook's timeline is to promote advertisements efficiently and help users create and exploit their digital autobiographies effectively. (Greenwald T. 2012)
BRIEF DESCRIPTIONS OF EXISTING METHODS
Prior to the Facebook's timeline, search engines such as Google, Yahoo mathematically index the web by scanning through pages for hyperlinks and will rank a page in its search results according to its listing rate on the Web. This method of indexing is still in use and not likely to be replaced by social indexing.
Likewise, news website have tried to personalize what they offer by collecting your past behaviour and provide information they presume is likely to interest you. (Simonite T. 2011).
SIGNIFICANCE OF FACEBOOK'S TIMELINE
Facebook implements a like button designed with a thumb up logo, sometimes linked to third-party websites to feed its timeline interface of user's interests, opinions on a web content - topic, product etc. and also to collect personal data of users and friends of related likeness which can then be used by marketers to build an accurate demography such as gender, income bracket, age bracket of their market.
ADVANTAGES OF TIMELINE
Timeline proves to be resourceful to mine and refine users' information and interests along with that of every person digitally linked to them.
Social indexing is less vulnerable to the manipulation that many SEO companies engage in to falsify the true rank of a site by self creation of links on multiple pages.
Timeline provides Facebook with more accurate personal data of users.
Its efficient data mining allow for companies to advertise to potential customers effectively.
DISADVANTAGES OF TIMELINE
Facebook's timeline will be of less use to people who don't have any evident online presence.
It is has a high potential to impinge on user's rights and privacy.
Unproductive companies using social indexing could later find it to be an uncontainable monster on resources - cost, servers and storage devices.
They make permanent record of our digital diaries which can be made available and accessible to unscrupulous individuals or companies.
THE FUTURE OF TIMELINE
According to Simonite (2011) 10,000 additional websites connect themselves to Facebook every day. The future holds for Facebook and the digital world if the Timeline is constantly tuned to be more accurate, speedy and scalable. The more the Web implements Timeline interface, the better it would become oriented around people. Social index would be much more powerful in mining web users' information and interests and this would mean quicker and easier searching for products, services, music playlists, news, topics etc. that may be of interest to web users.
CONCLUSION
Facebook's Timeline has great potential for the future by constantly fine-tuning the interface to make online services more customized to what a user really likes and wants. Thus, it can be concluded that social indexing can be used effectively to make people access their want more readily with minimal input in searching but with the aid of a digital diary of their personal setting.
