Patent ID: 9171930
Filing Date: 2015-10-27
Classification: H01L

Abstract:
1. A method of manufacturing a semiconductor device, comprising: sequentially forming an n-type epitaxial layer, a p-type epitaxial layer, and an n+ region on a first surface of an n+ type silicon carbide substrate; forming a buffer layer on the n+ region; forming a photosensitive film pattern on a part of the buffer layer; etching the buffer layer using the photosensitive film pattern as a mask to form a buffer layer pattern which is disposed below the photosensitive film pattern and exposes a part of the n+ region; sequentially forming a first metal layer and a second metal layer which both include first portions disposed on the n+ region and second portions disposed on the photosensitive film pattern on the exposed part of the n+ region and the photosensitive film pattern; removing the buffer layer pattern, the photosensitive film pattern, the second portion of the first metal layer, and the second portion of the second metal layer to expose the part of the n+ region; and etching the exposed part of the n+ region using the first portion of the first metal layer and the first portion of the second metal layer as masks to form a trench, wherein the trench passes through the n+ region and the p-type epitaxial layer and is formed on the n-type epitaxial layer.