Patent ID: 7635644

Claim:
A method of forming a metal interconnection, the method comprising the steps of: forming first and second interlayer dielectric layers on a substrate having a predetermined pattern; performing a chemical mechanical polishing process to planarize the second interlayer dielectric layer; selectively etching the first and second interlayer dielectric layers only up to a top surface of the pattern, thereby forming a contact hole for exposing the pattern; forming a slope by etching a corner of the contact hole; forming a barrier metal layer only on side surfaces of the first interlayer dielectric layer and on top and side surfaces of the second interlayer dielectric layer including the contact hole, wherein the barrier metal layer only partially covers the top surface of the pattern; forming a tungsten layer on the barrier metal layer including the contact hole, wherein the tungsten layer directly contacts the top surface of the pattern; and performing a chemical mechanical polishing process on the tungsten layer until the second interlayer dielectric layer is exposed.