Patents by Inventor Kiron B. Malwankar

Kiron B. Malwankar 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 system for calibrating an ellipsometer
    Patent number: 5581350
    Abstract: A method for calibrating an ellipsometer, and an ellipsometer including a processor programmed to control the analyzer, polarizer, and other ellipsometer components, and to process the data measured by the ellipsometer to perform the calibration method automatically. Where the ellipsometer's polarizer rotates and the analyzer remains fixed during measurement, the method determines coarse approximations of values A.sub.0 and P.sub.0, and then processes reflectivity data obtained at two or more analyzer angles to determine refined approximations of the values A.sub.0 and P.sub.0, where P.sub.0 is the angle of the polarizer's optical axis at an initial time, and A.sub.0 is the offset of the actual orientation angle of the analyzer from a nominal analyzer angle. Preferably the ellipsometer is a spectroscopic ellipsometer, the reflectivity data determine a tan.psi. spectrum and a cos.DELTA. spectrum for each of the analyzer angles, and the coarse approximations of A.sub.0 and P.sub.
    Type: Grant
    Filed: June 6, 1995
    Date of Patent: December 3, 1996
    Assignee: Tencor Instruments
    Inventors: Xing Chen, Philip D. Flanner, III, Kiron B. Malwankar, Jennming Chen