Patent ID: 8586478
Filing Date: 2013-11-19
Classification: H01L

Abstract:
1. A method of forming a semiconductor device comprising: forming a first mask having a first pattern defining a grooved area, said first mask overlying a metal film formed in an interconnect dielectric layer of said semiconductor device, wherein said first mask is formed by sidewall image transfer; forming a second mask having at least one opening overlapping said first pattern to form a second pattern, said second mask overlying said first mask and said opening overlapping said grooved area in plan view; etching the interconnect dielectric layer through said first and second masks, to transfer said first pattern to said interconnect dielectric layer; and etching the interconnect dielectric layer through said second mask, to transfer said second pattern to said interconnect dielectric layer; wherein said first pattern is formed in said interconnect dielectric layer to a different depth than said second pattern.