Rapid Thermal Processing of Polysilicon Emitter Bipolar Transistors in a Combined CMOS/Bipolar Process

The effect of RTA time on the emitter profiles and base current of polysilicon emitter bipolar transistors has been studied. Experimental results show increasing base current with anneal time. The contact saturation current density Jos has been extracted for a device with polysilicon doping level of 3×10 20 cm ?3 and a 45 second 1100°C RTA.