| 摘要 |
The present invention aims to suppress certainly the single-crystallizing in polycrystalline silicon that is to compose an emitter electrode, as well as to prevent the interface oxide film from remaining, when a heat treatment is conducted to diffuse dopants, and thereby it is also aimed to regulate the emitter dopant concentrations according to the design as well as to lower the emitter electrode resistance, which will provide a stable hFE; and further, the present invention aims to prevent anomalous bodies such as water-marks to be accidentally produced in a cleaning step following dry etching step to form an emitter electrode, and thereby to achieve an increase in yield as well as an enhancement of device reliability; in the process of the present invention, after an insulating film 4 and a first polycrystalline silicon film 5 are selectively dry etched to form a contact hole, a substrate is cleaned with such a cleansing agent as that composed of ammonia, hydrogen peroxide and water.
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