Pedestal Bipolar Transistor with Polysilicon Active Base and Emitter Which Achieves Minimized Capacitances

Bipolar transistors using a boron doped polysilicon layer for the intrinsic (on monocrystalline silicon) and extrinsic base regions (on field oxide), and a phosphorous doped polysilicon emitter, have been realized with upward current gains up to 10. The process is based on standard polysilicon film deposition followed by doping dependent recrystallization.