MANUFACTURING METHOD FOR INSULATION GATE TYPE SEMICONDUCTOR DEVICE AND INSULATION GATE TYPE SEMICONDUCTOR DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a high breakdown voltage for an insulation gate type semiconductor device.SOLUTION: The manufacturing method for insulation gate type semiconductor device, performing switching between a surface electrode and a back electrode, includes: a step of injecting first second-conduction-type impurities into a bottom face of a gate trench 34 and diffusing the injected first second-conduction-type impurities, and a step of injecting second second-conduction-type impurities into a bottom face of an outer peripheral trench 54 and diffusing the injected second second-conduction-type impurities.