Patent ID: 7473639
Filing Date: 2009-01-06
Classification: H01L

Abstract:
1. A method of forming a dual damascene pattern, the method comprising the steps of: forming a preliminary via hole exposing a part of a first etch stop layer in an insulating layer structure comprising a first dielectric layer, a second etch stop layer, and a second dielectric layer on the first etch stop layer; forming a sacrificial layer in the preliminary via hole; forming a mask pattern on the insulating layer structure; forming a trench exposing the second etch stop layer and the sacrificial layer by patterning the second dielectric layer and a part of the sacrificial layer using the mask pattern as an etch mask in an etching apparatus; and forming a via hole by removing the sacrificial layer pattern in the preliminary via hole and the mask pattern in-situ through an ashing process using the same etching apparatus, wherein the ashing process comprises treating the substrate with a first plasma phase from a first gas mixture comprising CF