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AssigneeInternational Business Machines Corporation
InventorsThomas R. Fisher, Jr., Mark A. Jaso, Leonard C. Stevens, Jr.
Estimating the term…
A method and apparatus for monitoring polishing pad wear during processing is developed to extend the pad's useful life, and maintain pad uniformity. This is accomplished in the present invention by measuring and monitoring the diminished pad thickness using a non-intrusive measurement system, and creating a closed-loop system for adjusting the chemical-mechanical polishing tool process parameters. The non-intrusive measurement system consists of an interferometer measurement technique utilizing ultrasound or electromagnetic radiation transmitters and receivers aligned to cover any portion of the radial length of a polishing pad surface. The measurement system is sensitive to relative changes in pad thickness for uniformity, and to abrupt changes such as detecting wafer detachment from the CMP wafer carrier.
A method for monitoring a polishing pad of a chemical-mechanical polishing tool, said pad having an initial thickness uniformity, and adjusting pad conditioning operational parameters comprising the steps of:
An apparatus for monitoring the thickness and thickness uniformity of a polishing pad used in a chemical-mechanical polishing process, comprising:
Dependencies are inferred from the claim text.