摘要 |
Interconnects to an underlying Cu feature are formed with improved reliability by replacing a portion of the capping layer in the bottom of an opening in an overlying dielectric layer, e.g., an ILD, with a barrier material, such as Ta or TaN. During Ar sputter etching to round the ILD corners, the exposed barrier layer portion is removed and redeposited to form a liner on the side surfaces of the dielectric layer defining the opening, thereby avoiding Cu redeposition on, and/or penetration through, the side surfaces of the dielectric layer.
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