In this chapter, a review of the present status of the fabrication and characterization of Si HFETs in the Si/SiGe and SiGeC material systems is presented. Heterojunction MOSFETs may use a strained SiGe/SiGeC channel or strained Si or strained Ge channel. The substrate for a compressively (tensilely) strained channel would have a lower (larger) lattice constant. The channels may lie on the surface or be buried. The other freedom is to use a vertical channel. The choice of the cap layer for a buried SiGe channel is an important issue having bearing on the performance of the device. A brief discussion of design considerations is given.
Heterostructure Field Effect Transistors, Page 1 of 2
< Previous page Next page > /docserver/preview/fulltext/books/cs/pbcs012e/PBCS012E_ch6-1.gif /docserver/preview/fulltext/books/cs/pbcs012e/PBCS012E_ch6-2.gif