摘要 |
A method for electrochemical mechanical polishing (ECMP) is disclosed. The polishing rate and surface finish of the layer on the wafer are improved by controlling the surface speed of both the platen and head, controlling the current applied to the pad, and preselecting the density of the perforations on the fully conductive polishing pad. ECMP produces much higher removal rates, good surface finishes, and good planarization efficiency at a lower down force. Generally, increasing the surface speed of both the platen and the head will increase the surface smoothness. Also, increasing the current density on the wafer will increase the surface smoothness. There is virtually no difference in the smoothness of the wafer surface between the center, middle, and edge of the wafer. For copper, removal rates of 10,000 Å/min and greater can be achieved.
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