International Business Machines Corporation

Leonard C Stevens, Jr

Mark A Jaso

Thomas R Fisher, Jr

Michael F Lofaro

Karl E Boggs

Marc Mattaroccia

A semiconductor wafer is cleaned while a sponge or brush is pressed against the wafer with a constant forced applied utilizing a bias in a constant force pencil. The wafer is cleaned in the state wherein a collapsing portion of the constant force pencil with respect to the cleaning sponge cloth is set in such a way that the cleaning pressure, which is applied from the cleaning sponge to the wafer, can be constant and is adjustable. A method for cleaning wafers using a constant force pencil is also described.

Apparatus and method for wafer cleaning

In a chemical-mechanical polishing (CMP) process, semiconductor substrates are rotated against a polishing pad in order to planarize substrate layers. The condition of the polishing pad directly affects the polishing rate of material removal and uniformity of removal from the semiconductor wafer. Conditioning of the polishing pad surface with an abrasive improves polishing uniformity and rates, however, it has the detrimental affect of removing a quantity of pad material. 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.

Method and apparatus for monitoring polishing pad wear during processing

A cleaning pad and roller assembly for cleaning semiconductor wafers. The pad may be a felt sheet with a pair of tabs located at opposite ends. The roller may be polyvinylchloride and may have a drive gear at one end and a clamp at each end. Each clamp is a clamping lever mounted on a shelf and may be locked in place by a clamping screw. Each clamping lever may have a pivot at one end and a serrated surface at an opposite end. The clamping screw may pass through the clamping lever into the shelf.

Pad and roller assembly for cleaning semiconductor wafers

A chemical mechanical polishing apparatus comprises a delivery system for supplying a slurry, wherein the slurry includes suspended particles and at least one acoustic element, connected to the delivery system, the acoustic element generating sound waves for agitating the slurry and maintaining the particles in suspension.

Acoustically agitated delivery

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.

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Poughquag, NY, United States of America

Leonard C Stevens, Jr