Patents by Inventor Thorbjoern R. Fredriksen

Thorbjoern R. Fredriksen 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: 4328553
    Abstract: A method and apparatus for targetless X, Y and .theta. alignment of a semiconductor wafer having thereon a large number of identical microcircuits or dies that are arranged in a pattern to form rows and columns separated by scribe lines or "streets." The orientation of the wafer is defined by the location of the wafer flat. Each one of the scribe lines or "streets" has a known angular relationship with the wafer flat. The alignment method and apparatus utilizes the wafer "street" pattern for identification instead of special targets located on the wafer. Coarse alignment of the wafer is achieved by locating the wafer flat and then rotating the wafer into approximately correct orientation. Fine alignment of the wafer is performed by opto-electrically locating the edge of a "street" and then rotating the wafer until the "street" edge is parallel to either the X or Y principal axis.
    Type: Grant
    Filed: September 8, 1980
    Date of Patent: May 4, 1982
    Assignee: Computervision Corporation
    Inventors: Thorbjoern R. Fredriksen, Philippe Villers