Patent ID: 6906401

Claim:
A structure comprising: a base region having a monocrystalline region located atop a Si substrate and polycrystalline regions located atop trench isolation regions that are present in the Si substrate, with said monocrystalline region separating the polycrystalline regions; a patterned emitter landing pad stack atop portions of the monocrystalline region, said patterned emitter landing pad stack comprising at least a bottom oxide; a raised extrinsic base located atop the polycrystalline regions of the structure and part of the monocrystalline region that does not contain said patterned emitter landing pad stack; an emitter opening located above said monocrystalline region, said emitter opening is defined by said patterned emitter landing pad stack; and an emitter region located in said emitter opening.