SiGe HBT Technology

Abstract

Advances in silicon–germanium (SiGe) heterojunction bipolar transistor (HBT) technologies resulted in an impressive increase in high-frequency performance during the last decade extending the addressed application frequencies into the mm- and sub-mm-wave bands. Today, SiGe HBTs are widely used for applications like automotive radar, high-speed wireless and optical data links, and high-precision analog circuits. BiCMOS technologies which comprise high-speed SiGe HBTs in a radio-frequency (RF) CMOS technology environment combine the excellent RF performance of SiGe HBTs with the high level of integration and the high computing power of Si CMOS. These technologies became a key enabler for demanding mm-wave systems which integrate radio front-end circuits together with digital control circuits and signal processing on a single chip. Previous development has demonstrated that SiGe HBTs continue to offer significantly higher cutoff frequencies, higher output power, and superior analog characteristics compared to CMOS transistors of the same lithography node. Thus, the integration of SiGe HBTs in a CMOS platform represents a very attractive option to boost the RF performance of a given technology node.