| 摘要 |
PURPOSE:To form a flat insulating film on the entire region on an epitaxial layer and to improve the effect of preventing breading at a step part, by forming gentle opening windows for a base contact window, a collector contact window and other contact windows simultaneously by the same method, when an insulating film is made to remain at the side wall of an emitter window and the vicinity thereof. CONSTITUTION:A third oxide insulating film is removed by a washing-out method, and an emitter contact window 11 is formed. A base contact window 12 and a collector window 13 are formed in a second oxide insulating film 8 by an ordinary photoetching method. Then, a fourth oxide insulating film 14 is grown on the entire surface by a CVD method. Thereafter, anisotropic reactive ion etching is performed on the entire surface. A side wall 14a of the fourth oxide insulating film is made to remain at the side wall of the window and the vicinity thereof. Then, an emitter electrode 15, a base electrode 16 and a collector electrode 17 comprising aluminum silicon alloy or high melting point metal are formed. Thus, the breading of interconnection metal due to the step part in the insulating film does not occur, and the risks of short- circuit between the emitter and the base are remarkably less.
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