Patent ID: 7491617

Claim:
A method of forming a bipolar transistor comprising the steps of: forming a first conductivity first epitaxially grown silicon-containing layer atop second conductivity portion of a substrate; forming at least two isolation regions in said first conductivity epitaxially grown silicon-containing layer, wherein an active area is formed between said at least two isolation regions; forming a base window dielectric layer atop said first conductivity epitaxially grown silicon-containing layer and said at least two isolation regions; wherein said base window dielectric layer is removed within said active area; forming first conductivity second epitaxial extrinsic base regions, each first conductivity epitaxial base region of said first conductivity extrinsic base regions separated by an emitter channel, said emitter channel exposing a portion of said first conductivity epitaxially grown silicon-containing layer; and forming a second conductivity emitter within said emitter channel, wherein said emitter is separated from said first conductivity extrinsic base regions by emitter/base spacers.