Abstract: A method for manufacturing BiCMOS semiconductor devices in which an oxide layer formed on the surface of a semiconductor substrate for the purpose of facilitating formation of spacers adjacent to sidewalls of the gates of the MOS transistors thereof is only partially removed, by using a dry etching process, to thereby leave a residual oxide layer, which is then removed, by using a wet etching process, to thereby form the spacers. Alternatively, all portions of the oxide layer except a portion thereof overlying the base-emitter region of the bipolar transistor of the BiCMOS device is removed, thereby precluding the necessity of etching the oxide layer away at the base-emitter junction. In either case, the DC forward current gain Hfe and linearity of the bipolar transistor of the BiCMOS device are enhanced.

Abstract: A method for manufacturing BiCMOS semiconductor devices in which an oxide layer formed on the surf ace of a semiconductor substrate for the purpose of facilitating formation of spacers adjacent to sidewalls of the gates of the MOS transistors thereof is only partially removed, by using a dry etching process, to thereby leave a residual oxide layer, which is then removed, by using a wet etching process, to thereby form the spacers. Alternatively, all portions of the oxide layer except a portion thereof overlying the base-emitter region of the bipolar transistor of the BiCMOS device is removed, thereby precluding the necessity of etching the oxide layer away at the base-emitter junction. In either case, the DC forward current gain Hfe and linearity of the bipolar transistor of the BiCMOS device are enhanced.

Abstract: The present invention relates to a method for manufacturing BiCMOS device. The emitter of bipolar transistor and the load resistors of CMOS transistors are formed in such a manner that the amorphous silicon layer is formed at a low temperature in order to prevent an oxide layer from forming on the exposed base region and then the ion impurities are implanted into this region so as to be annealed and oxidized, where the ion impurities are not implanted into the load resistor portion. Thus, any oxide layer is scarcely formed between the emitter region and polysilicon layers. And the resistance becomes substantially low since the amorphous silicon layer is changed to the polysilicon layer with large grains and the emitter region is formed by diffusing the ion impurities.In addition, the polysilicon layer for the load resistors of CMOS transistors is intrinsic and has large grain, thereby making the resistance value high.