Method of forming a bipolar transistor with maskless self-aligned emitter

摘要

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.

主权项

1. A method of forming a semiconductor emitter, the method comprising the steps of:
forming at least an epitaxial base layer on a semiconductor substrate; depositing a dielectric layer directly on top of the epitaxial base layer, which is used as an etch stop to protect the epitaxial base layer during a subsequent etching process; etching a portion of the dielectric layer to form an opening exposing at least a portion of the epitaxial base layer; depositing a spacer along a sidewall of the opening, wherein a portion of the dielectric layer extends past the sidewall in a plane parallel to the epitaxial base layer; and forming an emitter, where the emitter grows from the epitaxial base layer in a <100> crystal direction to overlap a top surface of the spacer and a portion of the dielectric layer.