Patent ID: 6118171
Filing Date: 2000-09-12
Classification: H01L

Abstract:
A semiconductor device comprising:a semiconductor substrate;a pedestal structure overlying the semiconductor substrate, wherein the pedestal structure has an upper surface, sides, a corner, the corner having a tapered profile that curves inward from the sides of the pedestal structure to the upper surface of the pedestal structure;an emitter structure overlying the upper surface of the pedestal structure, wherein the emitter structure includes:a first layer of undoped material; anda core comprising doped material, wherein the core is encompassed by the first layer of undoped material;a base region, a collector region, and an emitter region in the pedestal structure;a first doped region in the semiconductor substrate;a plug structure that is electrically coupled to the collector region by the first doped region; anda conductive layer that contacts the corner of the pedestal structure and is electrically coupled to the base region.