Performance analysis of a bandgap engineered Silicon bipolar transistor

Silicon-Germanium Heterojunction Bipolar Transistor (SiGe HBTs) represents the first practical bandgap-engineered Silicon-based transistor. The design issues related to SiGe HBT that makes it suitable for high speed application has been explored. Emphasis has been given to the requirement of low base resistance for achieving a reasonable value of gain at a high frequency. Compared to Silicon bipolar transistors much higher values of gain are obtained for such HBTs.