Book excerpt: Volume 41 includes an in-depth review of the most important, high-speed switches made with heterojunction technology. This volume is aimed at the graduate student or working researcher who needs a broad overview andan introduction to current literature. - The first complete review of InP-based HFETs and complementary HFETs, which promise very low power and high speed - Offers a complete, three-chapter review of resonant tunneling - Provides an emphasis on circuits as well as devices