ABSTRACT
Significant increases in the operating frequency range of silicon semiconductor devices over the past
decade have made low-cost electronic equipment available to the consumers at spectacular performance
levels. The development of techniques to make silicon-based heterojunction bipolar transistors (HBTs)
using SiGe and, later, SiGe:C, was responsible for great strides forward in bipolar transistor performance.
An important way to use HBTs is to combine them with high-performance CMOS and well-character-
ized passive components in monolithic integrated circuit processes designated BiCMOS. Philips has
manufactured RF BiCMOS products in the QUBiC family since 1989. SiGe HBTs were added to the
process in 2002 and SiGe:C HBTs were added in 2004.