Patents by Inventor Timothy Scott Bullard

Timothy Scott Bullard has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6352596
    Abstract: A method of detecting the presence of a brush used in a semiconductor wafer cleaner for post-CMP processing is described. Semiconductor wafers are loaded into the wet environment of the wafer cleaner, affixed to a rotatable fixture and rotated at high speed. The rotatable fixture is effectuated by a servo motor linked to a servo controller and a torque monitor. A first torque on the rotating wafer is calculated prior to the start of the brush cleaning cycle. During the brush cleaning cycle, as the brush within the brush cleaner contacts the rotating wafer, the torque on the wafer increases and a second torque is calculated. If, during the brush cleaning cycle, the second torque calculation is substantially equal to the first torque calculation, the brush cleaner is not contacting the wafer and cleaning has not progressed. A tool user can be notified to reaffix the brush within the cleaner.
    Type: Grant
    Filed: June 7, 2001
    Date of Patent: March 5, 2002
    Assignee: International Business Machines Corporation
    Inventors: Gary Joseph Beardsley, Timothy Scott Bullard, Cuc Kim Huynh, Theodore Gerard van Kessel, David Louis Walker
  • Patent number: 6269510
    Abstract: An apparatus for and method of detecting the presence of a brush used in a semiconductor wafer cleaner for post-CMP processing is described. Semiconductor wafers are loaded into the wet environment of the wafer cleaner, affixed to a rotatable fixture and rotated at high speed. The rotatable fixture is effectuated by a servo motor linked to a servo controller and a torque monitor. A first torque on the rotating wafer is calculated prior to the start of the brush cleaning cycle. During the brush cleaning cycle, as the brush within the brush cleaner contacts the rotating wafer, the torque on the wafer increases and a second torque is calculated. If, during the brush cleaning cycle, the second torque calculation is substantially equal to the first torque calculation, the brush cleaner is not contacting the wafer and cleaning has not progressed. A tool user can be notified to reaffix the brush within the cleaner.
    Type: Grant
    Filed: January 4, 1999
    Date of Patent: August 7, 2001
    Assignee: International Business Machines Corporation
    Inventors: Gary Joseph Beardsley, Timothy Scott Bullard, Cuc Kim Huynh, Theodore Gerard van Kessel, David Louis Walker
  • Patent number: 6022266
    Abstract: An improved method of in-situ conditioning of a polishing pad for use with a stationary pad conditioner during chemical mechanical polishing is described. A polishing table having a polishing pad on its surface is rotated in a first direction during polishing of a semiconductor wafer. A polishing pad conditioner is adjustably attached to the rotating polishing table such that the conditioner is stationary in relation to the rotating polishing table. The conditioner has a roughened surface which is in contact with the polishing pad providing in-situ conditioning during polishing of a semiconductor wafer. After polishing of the semiconductor wafer, the polishing table is rotated in a second direction while the conditioner is still in contact with polishing pad. Rotating the polishing pad in a second direction dislodges the polishing debris clogging the roughened surface of the conditioner and redistributes CMP slurry.
    Type: Grant
    Filed: October 9, 1998
    Date of Patent: February 8, 2000
    Assignee: International Business Machines Corporation
    Inventors: Timothy Scott Bullard, Richard John Lebel, Rock Nadeau, Paul Henry Smith, Jr.