Conductive polishing pad with anode and cathode
AssigneeRohm and Haas Electronic Materials CMP Holdings, Inc.
InventorJoseph K. So
Life of this patent
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Abstract
A conductive polishing pad that includes one or more anodes and one or more cathodes formed at or near the polishing surface of a polishing pad. The anodes and cathodes are connected to a wiring network that is part of an electrical connector system that allows for a current source to be connected to the polishing pad and provide a current to the anodes and cathodes even if the polishing pad is moving relative to the current source. An electrolytic polishing fluid introduced between the polishing surface and the metal layer of a wafer forms an electrical circuit between the anode, cathode and the metal layer. The conductive polishing pad allows for electrochemical mechanical polishing (ECMP) to be performed on a conventional chemical mechanical polishing (CMP) tool.
Claims10
A polishing pad comprising:
- one or more anodes formed in the polishing pad at or near a polishing surface of the polishing pad;
- and
- one or more cathodes formed in the polishing pad at or near the polishing surface of the polishing pad and electrically isolated from the one or more anodes.
A method of using a chemical mechanical polishing (CMP) tool to perform electrochemical mechanical polishing (ECMP) of a substrate having metal formed thereon, the method comprising:
- providing a polishing pad having one or more anodes formed in the polishing pad at or near a polishing surface of the polishing pad, and one or wore cathodes formed in the polishing pad at or near the polishing surface of the polishing pad and electrically isolated from the one or more anodes;
- introducing an electrolytic polishing fluid between the substrate and the polishing surface so as to establish an electrical circuit between the one or more anodes, the metal, and the one or more cathodes;
- providing a current to the one or more anodes and the one or more cathodes to cause electrochemical migration of metal ions from the metal into the electrolytic polishing solution;
- and
- pressing the substrate against the polishing surface while moving at least one of the polishing pad and the substrate.
Dependencies are inferred from the claim text.