Patents by Inventor Alok K. Berry

Alok K. Berry 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).

  • Method and apparatus for non-destructively measuring local resistivity of semiconductors
    Patent number: 5379109
    Abstract: An apparatus for non-destructively measuring resistivity of a semiconductor, such as InP, comprises light sources for illuminating a preselected portion of the semiconductor with first and second light beams, each of a preselected single wavelength, the first light beam operating to excite the semiconductor by photo injecting carriers, and the second light beam bombarding the local portion of the semiconductor with a preselected photon energy. The apparatus measures a fractional change in reflectance of the second light beam responsive to the first light beam, and records this fractional change in reflectance for various values of photon energy of the second light beam, to generate a photoreflectance line-shape. The photoreflectance line-shape is used to calculate a photoreflectance line-shape phase angle, which is used to determine the resistivity of the preselected portion of the semiconductor.
    Type: Grant
    Filed: June 17, 1992
    Date of Patent: January 3, 1995
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: D. Kurt Gaskill, Nicholas Bottka, Alok K. Berry