Patent ID: 6740563
Filing Date: 2004-05-25
Classification: H01L

Abstract:
A method for fabricating a bipolar transistor comprising:providing a semiconductor substrate having formed therein: an intrinsic base region of a first polarity which includes a surface of the semiconductor substrate; an extrinsic base region of the first polarity formed adjoining the intrinsic base region; and a collector region of a second polarity opposite the first polarity formed within the semiconductor substrate and beneath the intrinsic base region; forming a polysilicon emitter layer upon the intrinsic base region and separated from the extrinsic base region; implanting first a portion of the intrinsic base region interposed between the extrinsic base region and the polysilicon emitter layer with an amorphizing non-active dopant; and implanting second the polysilicon emitter layer with an active dopant to form a doped polysilicon emitter layer.