preview

Literature Review

Decent Essays

UNIT 2
LITERATURE REVIEW
Early Work
Fabrication
2 LITERATURE REVIEW
2.1 Early Work
The influence of strain on the mobility of intrinsic silicon was first observed in 1954 by C.S Smith [19]. The origin of strained Si film grown on relaxed SiGe can be traced to the 1980s [19]. While strain effects were not largely exploited, it was in the early 1990s that the strain was once again revived at Massachusetts Institute of Technology (MIT), USA on process induced and biaxial strain. In 1992, the first n-channel MOSFET with a strained Si channel exhibiting a 70% higher mobility was demonstrated [19]. The commercial adoption of strain technology was followed in 90 nm technology node by all major semiconductor companies like AMD, Integrated …show more content…

However, as demonstrated by our results, there are undesirable side effects with increasing equivalent Ge content such as a roll off in Vth, which may affect the device characteristics and performance significantly.
In year 2007, M. J. Kumar et al[13] have first time examined the impact of various device parameters like strain (concentration of Ge in SiGe substrate), gate length, S/D junction depths, substrate (body) doping, strained silicon thin-film thickness and gate work function on the threshold voltage of strained-Si on Si1-xGexMOSFET. There is a significant drop in threshold voltage with increasing strain in relaxed Si1-xGex substrate and decreasing channel length. The increase in mole fraction of Ge, enhances the performance of MOSFETs in terms of transconductance and speed because of an increase in the carrier mobility. In the Same year V.Venkataraman [22], have also demonstrated fully depleted strained-Si on SGOI MOSFETs. This article also shows that there is significant increase in mobility due to strain.
In year 2010, A. Chaudhry have submitted a review of strained silicon technology. The uniaxial and biaxial structures proposed by both industry and academia via literature and patents have been reviewed. The main structures under biaxial category are relaxed SiGe, graded SiGe, strained SOI, SGOI and

Get Access