Design and Fabrication of High Speed NPN SiGe Heterojunction Bipolar Transistor

The paper presents the device structure and fabrication process of 0.18 μm high speed SiGe HBT.The DC and RF characteristics of SiGe HBT are analyzed with typical Ft=110 GHz,BVCEZ=1.8 V and β=270.The impact of different process conditions on SiGe HBT performance is investigated,including the doping of implanted collector,EPI SiGeC base and polysilicon emitter as well as the thickness of SiGeC base.The optimum process conditions are exhibited.