Design and simulation of silicon-germanium HBT for power applications at 10 GHz.

摘要

Power amplifiers are an integral part of most communication systems. The operation frequency of the communication systems like cell phones and LANs vary from 900MHz to 5.5GHz. For satellite communications the operating frequency is about 10 GHz. Hence the power amplifiers are required to work well at these frequencies. While a Si BJT works well for frequencies less than 2GHz, for high frequencies, III--V based transistors are used. Apart from being more expensive than the Si based technology, the III--V's cannot be integrated into Si based CMOS technology. Hence it is necessary to develop a power amplifier that can work at higher frequency that can be integrated into Si technology. With careful design and development, the SiGe power HBTs has the potential to replace III--V transistors. SiGe HBTs are cost effective and can be integrated into Si technology, thus making system on chip a reality. This work examines the epilayer design, geometrical layout and self-heating effects of a SiGe HBT in an effort to improve its high frequency performance.