International Business Machines Corporation

Thomas R Fisher, Jr

William Francis Landers

Mark A Jaso

Leonard C Stevens, Jr

Carol Elaine Gustafson

Michael F Lofaro

Matthew J Rutten

Adam D Ticknor

Thomas Edwin Sandwick

Dean Allen Schaffer

John Carlo Minunni, Jr

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 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 of monitoring polishing pad wear during processing

A wafer carrier assembly including a subassembly for in-situ nondestructive pad conditioning, characterized by continuously cleansing the pad surface with an energized fluid. The fluid may be abrasive in nature, such as a slurry, or non-abrasive, such as DeIonized (DI) water. In addition, the fluid may be of a type known to assist in removing slurry and/or residual materials from a pad surface and followed by a DI water rinse. The chemical may be either liquid or gas.

Wafer carrier assembly

A vertically-oriented wafer polishing apparatus and method is disclosed including a vertically-oriented polishing device, a semiconductor wafer carrier and a cleaning module to clean the polishing device by removing contaminants that may scratch the wafer and also reduce the polishing rate of the apparatus. The device reduces the 'down time' of a polishing apparatus and, therefore, increases the yield of well-polished wafers in a given time period.

Vertical polishing tool and method

An improved Chemical Mechanical Planarization (CMP) method is provided for selectively removing a layer of metallization material such as tungsten or copper and a liner film such as Ti/Tin or Ta/TaN from the surface of an oxide layer of a semiconductor wafer. The method includes removing the metallization and liner layers with a first removal process which utilizes CMP polishing and an alumina-based slurry. The first removal process is stopped after the metallization layer is completely removed and before the liner film is completely removed. The remainder of the liner film is removed using a second removal process which includes CMP polishing using a neutral pH silica-based slurry which is selective to the liner film.

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Beacon, NY, United States of America

Thomas R Fisher, Jr