METHOD OF MANUFACTURING A BIPOLAR TRANSISTOR AND BIPOLAR TRANSITOR OBTAINED THEREWITH

摘要

The invention relates to a method of manufacturing a semiconductor device (10) comprising a substrate (12) and a silicon semiconductor body (11) and comprising a bipolar transistor with an emitter region (1) of a first conductivity type, a base region (2) of a second conductivity type opposite to the first conductivity type, and a collector region (3) of the first conductivity type, on the surface of the semiconductor body (11) in which the collector region (3) is formed at least an epitaxial semiconductor layer (20,21,22) being deposited in which the base region (2) is formed, on top of this an etch stop layer (15) being deposited on which a silicon low-crystalline semiconductor layer (24) is deposited in which a connection zone of the base region (2) is formed and in which at the location of an emitter region (1) to be formed an opening (7) is provided running up to the etch stop layer (15), a portion of the etch stop layer (15) covering the opening (7) being removed by means of etching and also an adjoining portion of the etch stop layer (15), a hollow being created underneath the silicon low-crystalline semiconductor layer (24) adjoining and connected the opening (7), whereinafter a high-crystalline semiconductor layer (5) is formed within the hollow. In a method according to the invention the formation of the high-crystalline semiconductor layer (5) is carried out in such a way that a part of the surface of the semiconductor body (11) adjoining the opening (7) is kept free from the high-crystalline semiconductor layer (5). In this way a high-quality device (10) is obtained in easy manner. The relevant surface is kept free using a cover layer (6) or in a preferred manner even without the use of such a layer.