Semiconductor device
Abstract
Abstract PURPOSE:To restrict surface recombination and improve a current amplification factor by providing the surface layer of the base region in a horizontal PNP transistor with a layer, wherein the maximum concentration of N type impurities is distributed on the surface side, for instance, through injection of ions. CONSTITUTION:An N type epitaxial layer 3 is formed on a substrate 1 provided with a burried layer 2 and the epitaxial layer 3 is provided with a diffused isolation layer 4 then to form an emitter region 5, collector regin 6, base taking out diffusion layer 7 and a channel stopper layer 8 masked by an oxide film. Next, the oxide film used as a diffusion mask is removed to again form a thermal oxide film 9, then, for instance, phosphor is injected into the surface layer of the base region masked by a resist 11 to form an N region 12 wherein the maximum concentration of phosphor is distributed on the surface side. Subsequently the resist 11 is removed to form a circuit element after various process of piling up of an interlayer film 13, forming of a contact window and forming a electrodes. Thereby, an internal electric field restrict the surface recombination of minority carriers injected into the base region 10 to improve a current amplification factor of the horizontal PNP transistor.
Inventors
- 👤 Takashi Yasujima
- 👤 Jiro Oshima
- 👤 Toshio Yonezawa
Bibliographic Details
Claims Analysis
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