Patents by Inventor Robert M. Silva, deceased

Robert M. Silva, deceased 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: 5032734
    Abstract: A method and apparatus are disclosed for nondestructively measuring the density and orientation of crystalline and other micro defects on and directly below the surface of a properly prepared material such as a semiconductor wafer. The material surface is illuminated with a probe beam of electromagnetic radiation which is limited to a nondestructive power level or levels. Polarization and wavelength or wavelengths of the electromagnetic radiation are selected according to certain characteristics of the material so that penetration depth is controlled. Specific orientation of the material with respect to the probe beam and the detector is required to detect that portion of the probe beam scattered from the defects of interest, surface or subsurface, without interference from other scatter sources and to identify the orientation of the defects. Maps of scatter intensity versus position are made according to the density of the defects encountered.
    Type: Grant
    Filed: October 15, 1990
    Date of Patent: July 16, 1991
    Assignee: VTI, Inc.
    Inventors: Fred D. Orazio, Jr., Robert B. Sledge, Jr., Robert M. Silva, deceased
  • Patent number: 4978862
    Abstract: A method and apparatus are disclosed for nondestructively measuring the density and orientation of crystalline and other micro defects on and directly below the surface of a properly prepared material such as a semiconductor wafer. The material surface is illuminated with a probe beam of electromagnetic radiation which is limited to a nondestructive power level or levels. Polarization and wavelength or wavelengths of the electromagnetic radiation are selected according to certain characteristics of the material so that penetration depth is controlled. Specific orientation of the material with respect to the probe beam and the detector is required to detect that portion of the probe beam scattered from the defects of interest, surface or subsurface, without interference from other scatter sources and to identify the orientation of the defects. Maps of scatter intensity versus position are made according to the density of the defects encountered.
    Type: Grant
    Filed: November 16, 1989
    Date of Patent: December 18, 1990
    Assignee: VTI, Inc.
    Inventors: Robert M. Silva, deceased, Fred D. Orazio, Jr., Robert B. Sledge, Jr.
  • Patent number: 4933567
    Abstract: A method and apparatus are disclosed for nondestructively measuring the density and orientation of crystalline and other micro defects directly below the surface of a properly prepared material such as a semiconductor wafer. The material surface is illuminated with a probe beam of electromagnetic radiation which is limited to a nondestructive power level and with a wavelength, or wavelengths, selected according to certain characteristics of the material so that penetration depth is controlled. Specific orientation of the material with respect to the probe beam and the detector is required to detect that portion of the probe beam scattered from the subsurface region without interference from the surface scatter and to identify the orientation of the defects. Maps of scatter intensity versus position are made according to the density of the defects in the subsurface.
    Type: Grant
    Filed: January 26, 1989
    Date of Patent: June 12, 1990
    Assignee: VTI, Inc.
    Inventors: Robert M. Silva, deceased, Fred D. Orazio, Jr., Robert B. Sledge, Jr.