Patents by Inventor Clifford G. Wells

Clifford G. Wells 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).

  • Apparatus for evaluating thermal and electrical characteristics in a sample
    Patent number: 5228776
    Abstract: An apparatus is disclosed for evaluating thermal and electrical characteristics of a sample. An intensity modulated pump beam is focused onto the surface of a sample at one spot. A non-modulated probe beam is focused onto the sample at a second spot, spaced laterally and vertically from the first spot. The distance between the two spots is at least two microns. The modulated power of the reflected probe beam that is in phase with the pump beam modulation frequency is monitored to provide information about the characteristics of the sample. The apparatus is particularly useful in evaluating the integrity of metal lines and vias in a semiconductor sample.
    Type: Grant
    Filed: May 6, 1992
    Date of Patent: July 20, 1993
    Assignee: Therma-Wave, Inc.
    Inventors: Walter L. Smith, Clifford G. Wells, Allan Rosencwaig