Patent ID: 7883835

Claim:
A method of double patterning a thin film on a substrate, comprising: preparing a film stack on said substrate, said film stack comprising said thin film formed on said substrate, an anti-reflective coating (ARC) layer formed on said thin film, and a mask layer formed on said ARC layer; forming a first pattern in said mask layer; partially forming said first pattern in said ARC layer by forming said first pattern to a first depth less than the thickness of said ARC layer; forming a second pattern in said mask layer, wherein said second pattern is spaced apart from and non-overlapping with said first pattern; partially forming said second pattern in said ARC layer by forming said second pattern to a second depth less than the thickness of said ARC layer; removing said mask layer; completing said partially forming of said first pattern and said second pattern in said ARC layer by etching said ARC layer; and transferring said first pattern and said second pattern to said thin film while substantially consuming said ARC layer.