Patent ID: 6249031
Filing Date: 2001-06-19
Classification: H01L

Abstract:
Lateral bipolar transistors with improved current gain on a semiconductor substrate comprised of:a silicon substrate having a first conductive type dopant;doped wells having a second conductive type dopant;field oxide isolation surrounding device areas on said substrate;a patterned polysilicon layer over a gate oxide layer on portions of said device areas over base areas in said wells for said lateral bipolar transistors and further said wells having a base contact doped with a second conductive type dopant;doped buried base regions of said second conductive type dopant under emitter areas and lying within said wells for improving said current gain of said lateral bipolar transistors;doped emitters of said first conductive type dopant formed over said buried base regions and making metallurgical junctions with said buried base regions and collectors formed from said first conductive type dopant to complete said lateral bipolar transistors with said improved current gain.