PURPOSE: To readily manufacture bipolar transistors of high density in a high yield at a high speed by forming a base leading electrode and an emitter electrode at an ultrafine separating interval by a self-alignment.

CONSTITUTION: After an oxide preventive film 26, an accumulated film 27 and an accumulated film 28 including an impurity are formed on an active region 23 of a transistor, a semiconductor film 30 is formed. Then, an impurity is diffused in the semiconductor film 30 from laminated films 26∼28 by a heat treatment. Then, a semiconductor film of an impurity diffused region having a fast etching rate is selectively removed by the difference of the etching rate of the film 30, and a region 30b in which the impurity is not diffused is allowed to remain. Subsequently, the films 26∼28 are implanted, and other conductive type impurity is implanted to the film 30b. Then, the films 27, 28 are removed, with the film 26 as a mask an insulating film 31 is formed on the film 30b. Then, the film 26 is removed, and windows for diffusing an emitter and contacting the emitter are formed.