This paper reviews the history, evolution, current status, and applications
of semiconductor devices for radio frequency (RF) applications. The most i
mportant developments and major milestones leading to modern high-performan
ce RF transistors are presented. Heterostructures, which are key elements f
or some advanced RF transistors, are described, and an overview of the diff
erent transistor types and their figures of merit is given. Applications of
RF transistors in civil RF systems with special emphasis on wireless commu
nication systems are addressed, and the issues of transistor reliability ar
e also briefly discussed. (C) 2001 Elsevier Science Ltd. All rights reserve
d.