Bipolar transistor with maskless self-aligned emitter

Abstract

Embodiments of the present invention include a method for forming a semiconductor emitter and the resulting structure. The invention comprises forming an epitaxial base layer on a semiconductor substrate. A dielectric layer is deposited over the epitaxial base layer. An opening is etched in a portion of the dielectric layer exposing a portion of the epitaxial base layer and a spacer is deposited along the sidewall of the opening. The emitter is grown from the epitaxial base layer to overlap the top surface of the spacer and a portion of the dielectric layer. The single crystal emitter is formed without a mask and without the requirement of subsequent patterning processes.

Dependencies are inferred from the claim text.