Lam Research Corporation

Xu Li

John Martin De Larios

Diane J Hymes

Yuexing Zhao

A cleaning solution, method, and apparatus for cleaning semiconductor substrates after chemical mechanical polishing of copper films is described. The present invention includes a cleaning solution which combines deionized water, an organic compound, and an ammonium compound in an acidic pH environment for cleaning the surface of a semiconductor substrate after polishing a copper layer. Such methods of cleaning semiconductor substrates after copper CMP alleviate the problems associated with brush loading and surface and subsurface contamination.

Cleaning solutions for semiconductor substrates after polishing of copper film

A cleaning solution for cleaning a semiconductor substrate is formed by mixing an amount of citric acid and an amount of ammonia in deionized water. In one embodiment, the amount of citric acid is in a range from about 0.18% by weight to about 0.22% by weight and the amount of ammonia is in a range from about 0.0225% by weight to about 0.0275% by weight, and the cleaning solution has a pH of about 4. A method for cleaning a semiconductor substrate having a polished copper layer in which a concentrated cleaning solution is mixed with deionized water proximate to a scrubbing apparatus also is described.

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Santa Clara, CA, United States of America

Xu Li