Advances in wireless communications and information processing systems require implementation of very high performance electronic systems. In recent years, SiGe heterojunction bipolar transistors (HBTs) have emerged as one of the leading contenders to satisfy these demands. The low emitter-base turn-on voltage and device scaling significantly reduce power consumption in circuit operation, while maintaining high speed. With the increasing demand placed on voice and data communications, transmitting, receiving, and processing information at high frequencies and high speeds, the use of SiGe bipolar transistors becomes increasingly important.