Patent ID: 6531783
Filing Date: 2003-03-11
Classification: H01L,Y10S

Abstract:
A contact structure on a semiconductor integrated circuit, comprising:a conductive element; a first dielectric layer overlying said conductive element; a second dielectric layer overlying said first dielectric layer; a third dielectric layer overlying said second dielectric layer, said third dielectric layer containing voids which allow a chemical wet etch to pass through said third dielectric layer to said second dielectric layer, wherein said second dielectric layer is made of material having a slower etching speed than said third dielectric layer; an opening through said first, second and third dielectric layers to expose a portion of said conductive element; said opening having an upper portion and a lower portion wherein the upper portion of said opening is the result of a chemical wet etch; a second conductive element overlying portions of said third dielectric layer and extending into said opening; wherein said second conductive element makes electrical contact with said first conductive element.