Patent ID: 9614052
Date: 2017-04-04
CPC Classifications: H01L

Claim:
1. A method comprising: forming a conductive layer comprising a bottom portion, and a sidewall portion over the bottom portion, wherein the sidewall portion is connected to an end of the bottom portion; forming an aluminum-containing layer over the bottom portion of the conductive layer, wherein an aluminum oxide layer is formed at a top surface of the aluminum-containing layer; forming a dielectric layer over the aluminum-containing layer; forming an opening in the dielectric layer to expose a top edge of the sidewall portion of the conductive layer, and a portion of the aluminum oxide layer; filling the opening with a barrier layer and a copper-containing material over the barrier layer; and removing excess portions of the barrier layer and the copper-containing material, wherein a portion of the barrier layer and a portion of the copper-containing material remain in the opening to form a contact plug, and wherein the barrier layer comprises a first bottom surface contacting a top surface of the aluminum oxide layer, and a second bottom surface contacting a top edge of the conductive layer.