Bernd Heinemann and Alexander Fox, IHP, Frankfurt, Germany

The addition of a small amount of C in the B-doped base layer of a npn SiGe heterojunction bipolar transistor (HBT) paved the way for exposing the high frequency (HF) performance potential of such devices more than 10 years ago. 1 Significantly, the suppression of thermal diffusion and point-defect...