Patent ID: 6174802
Filing Date: 2001-01-16
Classification: H01L

Abstract:
A method for forming a self aligned contact, comprising the steps of:a. providing a semiconductor structure, having sequentially a first conductive layer, a first dielectric layer, and a conductive structure thereover; said conductive structure having sidewalls with sidewall spacers thereon; said first conductive layer having a contact area thereon adjacent to said conductive structure; said conductive structure comprising at least one conductive layer having a hard mask thereover;b. forming an second dielectric layer over said sidewall spacers, said hard mask, and said first dielectric layer; whereby a keyhole is formed in said second dielectric layer;c. forming a contact opening in said first dielectric layer and said second dielectric layer over said contact area;d. forming a first contact layer in said contact opening and over said second dielectric layer; said first contact layer having poor step coverage properties; whereby said keyhole is plugged without being filled; ande. forming a second contact layer over said first contact layer.