STRAINED-SI HETEROSTRUCTURE FETS
In conventional Si technology, the complementary metal-oxide semiconductor dominates the integrated circuit market. Its popularity comes from the simplicity in processing, as well as high input impedance. However, p-channel devices are inferior to n-channel ones in terms of current drive capability and speed performance. This is a consequence of the lower mobility of holes compared to electrons in Si. In order to match the current drive capability of n-channel (n-MOS), p-channel (p-MOS) devices are designed to be about 2-3 times larger than that of n-MOS. This adversely aﬀects the level of integration and device speed.