Patent ID: 6706611
Filing Date: 2004-03-16
Classification: H01L

Abstract:
A method for forming a dual damascene opening, comprising:providing a substrate with a dielectric layer thereon; providing a first patterned photoresist on said dielectric layer to expose a first portion of said dielectric layer; implanting ions into said first portion of said dielectric layer in a depth of part of said dielectric layer under a masking of said first patterned photoresist so as to form a dense region in said first portion or said dielectric layer; removing said first patterned photoresist; providing a second patterned photoresist on said dielectric layer, said second patterned photoresist defining an etching opening for exposing at least part of said dense region and a second portion of said dielectric layer; performing an etching process whose by said second patterned photoresist to etch said dielectric layer under said etching opening until exposing said substrate wherein an etching rate of said dense region is lower than said second portion of said dielectric layer, whereby a trench region is formed in said dense region and a via region is formed in said second portion of said dielectric layer; and removing said second patterned photoresist to form said dual damascene opening having said trench region and said via region.