Method of manufacturing semiconductor device

摘要

A simplified method of manufacturing a semiconductor device is disclosed wherein a base region is formed on a silicon substrate and an impurity is diffused into the base region. Any insulating film present on the silcon substrate is removed, substrate and an even film of silicon dioxide is coated thereon. Emitter diffusion windows, base electrode windows, collector electrode windows and resistor electrode windows are formed in the silicon dioxide film and a uniform film of polycrystal silicon is deposited over the silicon dioxide film and the electrode windows. Impurities are diffused through the polycrystal silicon film at the emitter and collector windows but not through the base window. An aluminum electrode layer is formed on the polycrystal silicon layer and patterned to form an electrode wiring pattern. Subsequently, the polysilicon layer is removed in exposed areas utilizing the aluminum electrode layer as a mask.