SEMICONDUCTOR DEVICE MANUFACTURING METHOD

摘要

In the present invention, a reverse blocking IGBT is manufactured using a silicon wafer cut from a single crystal silicon ingot manufactured by means of a floating method using, as a raw material, a single crystal silicon ingot that is manufactured by means of the Czochralski method. An isolating layer to be formed for the purpose of ensuring the reverse blocking performance of the reverse blocking IGBT is formed by diffusing an impurity by thermal diffusion, said impurity having been introduced into the silicon wafer. The thermal diffusion for forming the isolating layer is performed in an inert gas atmosphere at 1,290°C or higher but lower than the melting point of silicon. Consequently, crystal defects are not generated in the silicon wafer, and reverse withstand voltage failures and forward direction failures are prevented from being generated in the reverse blocking IGBT, thereby improving the yield rate of the semiconductor element.