High Speed Deep Sub-Micron MOSFET using High Mobility Strained Silicon Channel

The purpose of this work is to determine the advantages gained by using high mobility strained silicon in MOSFETs. It is frequently argued that for deep submicron devices the important parameter is velocity saturation rather than mobility. Computer simulation has been used to demonstrate that improvements in the cut-off frequency, f
_t
, of around 50% in n-channel devices can be achieved in 0.1 μm MOSFETs by using a strained Si channel grown on a relaxed Si
_0.7
Ge
_0.3
buffer and separated from the Si/SiO
₂
interface by a SiGe capping layer. The saturation velocity in both cases is assumed to be the same.