Patent ID: 8673788
Filing Date: 2014-03-18
Classification: H01L

Abstract:
1. A method of fabricating a semiconductor device, comprising: providing a substrate, wherein the substrate includes a first trench having a first width and a second trench having a second width, wherein the first width is greater than the second width; forming a first layer of polysilicon on the substrate including in the first trench and the second trench, wherein the forming the first layer forms an indentation in the first layer in a region overlying the first trench; forming a second layer conformally on the first layer to form a conformal second layer, wherein the conformal second layer extends over the first trench and the second trench, and wherein the second layer is photoresist; dry etching the conformal second layer such that it is disposed only in the indentation; and after etching the conformal second layer, etching the first layer, wherein the etched second layer remains in the indentation during the etching of the first layer, and wherein the etching reduces a depth of the indentation by reducing a thickness of the first layer.