Design and Thermal Analysis of SiGe HBT With Composite Structure of Segmented Emitter and Non-uniform Finger Spacing

A novel multi-finger power SiGe heterojunction bipolar transistor (HBT) with segmented emitter and non-uniform finger spacing structure is proposed to improve thermal stability of HBT.Thermal simulation for a ten-finger power SiGe HBT with novel structure are conducted with ANSYS software.Three-dimensional temperature distribution on emitter fingers is obtained.Compared with traditional integrity structure or segmented emitter and uniform finger spacing structure,the maximum junction temperature,temperature distribution and heat-flux distribution are significantly improved.Thermal stability is effectively enhanced.