SiGe heterostructures for FET applications

The high room-temperature carrier mobilities which have recently been observed for both electrons and holes in Si/SiGe heterostructures and the possibility of further improvements offer the prospect of silicon-based field effect transistors (FETs) with performances matching those of bipolar transistors and III–V modulation-doped FETs. In this article the electrical properties of this semiconductor system and the associated materials challenges are discussed, and some of the more important device applications are reviewed.