POWER SEMICONDUCTOR DEVICE

摘要

In power semiconductor devices which switch at high speeds, there had been cases in which the flow of displacement current at the time of switching, in combination with the resistance of that path, generated high voltage which caused thin insulating films such as gate insulating films to break down and semiconductor devices to break. The semiconductor device disclosed here divides the p-type well region arranged at the outer circumference of the power semiconductor device into an inward side and outward side, is provided with a field oxide film, on the outward side well region until the inner circumference of that well region, which is thicker than the gate insulating film, and thereby is able to prevent the gate insulating film from breaking down from the voltage generated by displacement current flowing at the time of switching.