BIPOLAR TRANSISTOR AND ITS MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a dipolar transistor which has a high breakdown strength characteristic, which prevents the generation of a leakage current by movable ions, which prevents the degradation of an electric characteristic due to a thermal strain and which is of high reliability. SOLUTION: The bipolar transistor comprises a structure in which a base layer of a second conductivity type is sandwiched between an emitter layer and a collector layer of a first conductivity type. The base layer is composed mainly of SiGe which contains Ge in a desired amount. An exposed face which comprises at least the boundary interface between the base layer and the collector layer is covered with a coating member which is composed of gel-like or rubber-like silicone.