Patents by Inventor Johann Tam

Johann Tam 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: 5700046
    Abstract: A wafer gripper assembly comprises first and second gripping members movably supported relative to each other. A motor propels the gripping members linearly towards and away from each other. Preferably both gripping members are movably supported, and a rotary-to-linear translator produces equal and opposite linear movement of the gripping members. Typically, at least six contactor elements are defined on the pair of gripping members. The contactor elements include a vertically extending portion having an inwardly facing convex surface for contacting an edge of a wafer, and an inwardly extending flange for supporting a lower surface of the wafer.
    Type: Grant
    Filed: September 13, 1995
    Date of Patent: December 23, 1997
    Assignee: Silicon Valley Group, Inc.
    Inventors: Matthew J. Van Doren, Don Sauer, Alexander H. Slocum, David Pap Rocki, Johann Tam, Larry Gerszewski
  • Patent number: 4507078
    Abstract: A wafer handling method and apparatus insures proper centering of a wafer at a work station and controls the heat transferred to the wafer in a baking operation. The amount of heat transferred and the rate at which the heat is transferred to the wafer are regulated by controlling the distance between the wafer and a hot plate. The hot plate is maintained at a constant temperature higher than the bake out or equilibrium temperature to which the wafer is to be heated.
    Type: Grant
    Filed: March 28, 1983
    Date of Patent: March 26, 1985
    Assignee: Silicon Valley Group, Inc.
    Inventors: Johann Tam, Jalal Ashjaee, Nobuo B. Kuwaki, Tuan M. Ngo, Susan W. Kung
  • Patent number: 4313266
    Abstract: A method and apparatus for drying a wafer at a drying station includes a wafer holder which grips the wafer on its edge so that there is no contact with a face of the wafer. This eliminates contact areas which could cause stains on the face. A carriage mechanism brings a wet wafer into the drying station at one level and takes the dry wafer out of the drying station at a different level to prevent any contact between the dry wafer and residual moisture at the incoming level.
    Type: Grant
    Filed: May 1, 1980
    Date of Patent: February 2, 1982
    Assignee: The Silicon Valley Group, Inc.
    Inventor: Johann Tam
  • Patent number: 4227347
    Abstract: A drive mechanism for a wafer processing machine of the kind which holds a silicon wafer on a vacuum chuck and rotates the wafer for processing operations on the wafer periphery or upper surface incorporates a low-speed motor, a high-speed motor and an overrunning clutch. The low-speed motor is connected to a drive shaft for the chuck through the overrunning clutch and rotates the chuck and wafer at a relatively low and precisely-controlled speed while the edge of the wafer is contoured by a grinding wheel or while the upper surface is mechanically cleaned by a brush engaged with the upper surface of the wafer. The high-speed motor is directly connected to the drive shaft and, when energized for a rinsing and drying operation, rotates the chuck and wafer in the same direction of rotation as the low-speed motor but at high speed while the wafer is being rinsed and dried after the grinding or cleaning operation.
    Type: Grant
    Filed: September 14, 1978
    Date of Patent: October 14, 1980
    Assignee: Silicon Valley Group, Inc.
    Inventor: Johann Tam
  • Patent number: 4217977
    Abstract: A conveyor system for conveying a relatively fragile work piece, such as a silicon wafer, to and from a work station where one or more processing operations are performed on the work piece comprises two parallel conveyor belts. Each conveyor belt is mounted on a separate carriage, and the carriages are moveable laterally toward and away from each other during different periods of operation of the conveyor system and also to enable different size work pieces to be carried by the conveyor belts. The conveyor belts are driven by a drive belt system which comprises a fixed length, closed loop drive belt and a pulley arrangement operatively associated with the drive belt for accommodating lateral motion of the carriages while permitting drive of the conveyor belts at all lateral positions of the carriages and without any change in the length of the drive belt. The conveyor system also provides positive handling of the work piece during all conveying and processing operations to minimize breakage of the work piece.
    Type: Grant
    Filed: September 15, 1978
    Date of Patent: August 19, 1980
    Assignee: The Silicon Valley Group, Inc.
    Inventor: Johann Tam