Patent ID: 6372653
Filing Date: 2002-04-16
Classification: H01L

Abstract:
A method of forming a dual damascene structure, comprising the steps of:providing a substrate; sequentially forming a first dielectric layer, a heat diffusion layer and a second dielectric layer over the substrate; forming a first mask layer over the second dielectric layer, wherein the first mask layer has a via opening that exposes a portion of the second dielectric layer; forming a second mask layer over the first mask layer, wherein the second mask layer has a trench that exposes a portion of the first mask layer and the second dielectric layer; removing the second dielectric layer exposed by the via opening using the first mask layer as a hard mask and the heat diffusion layer as a stopping layer so that the via opening pattern is transferred to the second dielectric layer; removing the first mask layer that is exposed by the trench and the heat diffusion layer that is exposed by the via opening using the second mask layer and the second dielectric layer as a hard mask so that the trench pattern is transferred to the first mask layer and the via opening pattern is transferred to the heat diffusion layer; removing the second dielectric layer that is exposed by the trench and the first dielectric layer that is exposed by the via opening using the second mask layer and the heat diffusion layer as a mask so that a trench is formed in the second dielectric layer and a via opening is formed in the first dielectric layer; forming a metallic layer that fills the trench and the via opening; and removing the second mask layer.