Bipolar transistor with diffusion compensation

A bipolar transistor having an emitter region, a collector region, and a base intrinsic region, the emitter region, the collector region, and the base intrinsic region each having at least a portion thereof adjacent to a first isolation oxide region, the emitter region contacted by an emitter contact region, the base intrinsic region having a diffusion compensation region extending a small, predefined area into the collector region at a point where the base intrinsic region and the collector region abut a sidewall of the first isolation oxide region and underlyiing a portion of said emitter region which is contacting said emitter contact region, the base intrinsic region being formed by the steps of:

• a) forming a mask over the base intrinsic region;
• b) implanting dopants o a same conductivity type as said base intrinsic region in regions exposed by the mask;
• c) diffusing dopants from the implant laterally under a portion of the mask to form oxide diffusion compensation regions;
• d) etching the regions exposed by the mask;
• e) forming field oxide regions in the regions exposed by the mask;
• and
• f) forming an emitter contact on said emitter region, at least a portion of said diffusion compensation region underlying a portion of said emitter region which is contacting said emitter contact.