Patent ID: 8912099
Filing Date: 2014-12-16
Classification: H01L

Abstract:
1. A method of manufacturing a semiconductor device, comprising: forming a first layer of SiO on a semiconductor layer; forming a second layer of SiN on said first layer; forming a patterned mask on said second layer, wherein said patterned mask has a width and covers a portion of said second layer; etching and removing the portion of said second layer that is not covered by said patterned mask; wet etching said first layer, using a solution containing hydrofluoric acid, to a width which is less than the width of said patterned mask; after said wet etching, forming an insulating layer on said semiconductor layer; removing said first layer and said second layer to form an opening in said insulating layer; and forming a gate electrode on a surface of said semiconductor layer exposed through the opening, wherein in said wet etching, etching said first layer is faster than etching said second layer.