Patent ID: 7358182
Filing Date: 2008-04-15
Classification: H01L

Abstract:
1. A method, comprising: forming an organo-silicate glass layer over a substrate; forming a first hardmask layer over said organo-silicate glass layer; forming a second hardmask layer over said first hardmask layer; forming a first photoresist layer over said second hardmask layer; removing a region of said first photoresist layer; removing a region of said second hardmask layer where said second hardmask layer is not protected by said first photoresist layer using a first plasma etch process to define a wire pattern in said second hardmask layer; removing said first photoresist layer; forming a second photoresist layer over said second hardmask layer and exposed surfaces of said first hardmask layer; removing a region of said second photoresist layer; performing a second plasma etch process to remove a region of said first hardmask layer to define a via pattern in said first hardmask layer, said via pattern aligned at least partially within said wire pattern, said second plasma etch removing a less than whole portion of a first region of said organo-silicate glass layer where said organo-silicate layer is not protected by said first hardmask layer; removing said second photoresist layer; performing a third plasma etch process, said third plasma process removing said first hardmask layer in regions of said first hardmask layer not protected by said second hardmask layer, removing a less than whole portion of a second region of said organo-silicate glass layer within a perimeter of said wire pattern and removing an additional less than whole portion of said organo-silicate glass layer in said first region of said organo-silicate glass layer; and performing a fourth plasma etch process, said fourth plasma etch process removing an additional less than whole portion of said organo-silicate glass layer in said second region of said organo-silicate glass layer to form a wire trench and removing all remaining portions of said organo-silicate glass layer in said first region of said organo-silicate glass layer to form a via opening.