METHOD OF MANUFACTURING A SEMICONDUCTOR DEVICE WITH BICMOS CIRCUIT WITH BIPOLAR TRANSISTOR AND MOSE TRANSISTOR

摘要

A bipolar transistor 1 formed in a silicon body 3 provided with a field isolation region 4 for isolating the semiconductor regions 6 and 7 adjacent to the surface 5 of the silicon body 3 from each other; A method of manufacturing a semiconductor device including a MOS transistor (2) is disclosed. The first region 6 is used for a bipolar transistor and the second region 7 is used for a MOS transistor. A gate insulating layer 10 is formed in the second region. Next, an amorphous silicon electrode layer 11 is formed on the surface of the gate electrode 13, and the electrode layer is doped. Next, in this electrode layer, the emitter electrode 12 is formed in the first region and the gate electrode 13 Is formed in the second region. A doping layer is provided in the electrode layer by a first doping in the region of the first region and a second doping in the region of the second region, wherein the first doping is performed such that the emitter region of the transistor The second doping is performed at a concentration lower than the concentration of the first doping, while the second doping is performed at a concentration that is formed through diffusion from the emitter electrode to be formed. The relatively low doping levels prevent gate oxidation breakdown during plasma etching and ion implantation.