SEMICONDUCTOR DEVICE

摘要

PURPOSE:To prevent current breakdown by a method wherein the width of contact of the first semiconductor layer with the second semiconductor layer is formed larger than that of either one semiconductor layer of the first and second ones. CONSTITUTION:The rectangular region of the second semiconductor layer 14 formed under a contact hole 11 is formed by extension from under a polycrystalline Si layer 8 toward the first conductive layer 13. The width W2 of a region 15 etched at the time of etching the polycrystalline Si layer on the second semiconductor layer 14 is formed sufficiently larger than W1. This increase of area causes the decrease of resistance of the region 14 and has the strong property to current breakdown. Therefore, this device is endurable to the current breakdown when an over current is inputted.