Patent ID: 6552374
Filing Date: 2003-04-22
Classification: H01L

Abstract:
A bipolar device, comprising:an insulation film disposed on a surface of a substrate and including a silicon nitride layer, said film having a collector area provided therein with a vertical sidewall; a collector filled in the collector area and having a portion thereof protruding over the silicon nitride layer, said collector being formed into a mushroom shape; an oxide film enclosing only the sides of the protruding portion of the collector; a first base semiconductor electrode formed on the insulation film at a thickness corresponding to the height of the oxide film; and a base disposed in contacting relationship on the collector and having a side portion forming a second base semiconductor electrode extending over said oxide film and said first base semiconductor electrode wherein the oxide film defines the junction between the collector and the base, prevents leakage current therebetween, and minimizes the formation of parasitic capacitance across the junction.