Patent ID: 7425754
Filing Date: 2008-09-16
Classification: H01L

Abstract:
1. A bipolar transistor, comprising: a collector including a frustum-shaped collector pedestal having an at least substantially planar upper surface extending in lateral directions, a lower surface, and a slanted sidewall extending between said upper surface and said lower surface, wherein said upper surface has an area substantially less than an area of said lower surface; an intrinsic base overlying all of said area of said upper surface of said collector pedestal; an emitter overlying said intrinsic base; an extrinsic base conductively connected to said intrinsic base; and a first dielectric region laterally adjacent to said emitter; and a second dielectric region laterally adjacent to said collector pedestal, wherein an opening extends through said first and second dielectric regions, said opening defining edges of said first and second dielectric regions, said edges being aligned in a vertical direction transverse to said lateral directions, said emitter having an edge referenced to said edge of said first dielectric region and said collector pedestal having an edge referenced to said edge of said second dielectric region, such that said emitter is aligned with said collector pedestal.