Patent ID: 6420252
Filing Date: 2002-07-16
Classification: H01L

Abstract:
A method of forming a self-aligned contact on a semiconductor comprising:forming a layer of a dielectric material over a semiconductor; providing a photoresist layer over the dielectric layer; exposing the photoresist layer with a desired pattern and developing an opening in said photoresist layer; removing the dielectric material exposed through the photoresist layer opening to form a contact opening extending through the dielectric material to the semiconductor; after the step of removing the dielectric material for forming the contact opening extending through the dielectric material to the semiconductor, further eroding the photoresist layer so as to enlarge the size of the opening in the photoresist layer, wherein said dielectric material adjacent the contact opening is exposed through the enlarged opening of said photoresist layer; depositing a barrier metal in the enlarged opening of said photoresist layer and in the contact opening of said dielectric material, wherein said barrier metal overlies the exposed dielectric material; and depositing a contact metal atop said barrier metal, wherein said barrier metal prevents said contact metal from diffusing into said semiconductor.