Patents Represented by Attorney, Agent or Law Firm James D. Welch
  • System and method of applying xenon arc-lamps to provide 193 nm wavelengths
    Patent number: 7489400
    Abstract: Application of Xenon arc-lamps to provide UV/deep UV wavelengths in spectrophotometer, reflectometer, ellipsometer, polarimeter or the like systems.
    Type: Grant
    Filed: August 3, 2006
    Date of Patent: February 10, 2009
    Assignee: J.A. Woollam Co., Inc.
    Inventors: Ping He, Martin M. Liphardt, James D. Welch
  • Ellipsometric investigation of very thin films
    Patent number: 7483148
    Abstract: Use of spectroscopic data obtained by investigation of a witness sample having a relatively thick dielectric on a surface thereof during deposition of a thin film onto the witness sample and onto a process sample having no, or a relatively thin dielectric on its surface, in characterizing thin film deposited onto the process sample.
    Type: Grant
    Filed: March 16, 2007
    Date of Patent: January 27, 2009
    Assignee: J. A. Woollam Co., Inc.
    Inventor: Blaine D. Johs
  • Sample masking in ellipsometer and the like systems including detection of substrate backside reflections
    Patent number: 7477388
    Abstract: A system and method of preventing substrate backside reflected components in a beam of electromagnetic radiation caused to reflect from the surface of a sample in an ellipsometer or polarimeter system, involving placing a mask adjacent to the surface of the sample which allows electromagnetic radiation to access the sample over only a limited area, wherein the mask can include detector elements for collecting electromagnetic radiation reflected from the sample backside.
    Type: Grant
    Filed: May 24, 2006
    Date of Patent: January 13, 2009
    Assignee: J.A. Woollam Co., Inc.
    Inventors: Martin M. Liphardt, James D. Welch, Corey L. Bungay, John A. Woollam
  • Rotating compensator ellipsometer system with spatial filter equivalent
    Patent number: 7468794
    Abstract: Application of a spatial filter equivalent constructed from a converging lens and an optical fiber in rotating compensator ellipsometer systems, after a sample system. The purpose is to eliminate a radially outer annulus of a generally arbitrary Profile beam that presents with low intensity level irregular content, so that electromagnetic beam intensity is caused to quickly decay to zero as a function of radius.
    Type: Grant
    Filed: August 15, 2005
    Date of Patent: December 23, 2008
    Assignee: J.A. Woollam Co., Inc.
    Inventors: Martin M. Liphardt, Blaine D. Johs, Craig M. Herzinger, Ping He
  • Deviation angle self compensating substantially achromatic retarder
    Patent number: 7460230
    Abstract: A substantially achromatic multiple element compensator system for use in wide spectral range (for example, 190-1700 nm) rotating compensator spectroscopic ellipsometer and/or polarimeter systems. Multiple total internal reflections enter retardance into an entered beam of electromagnetic radiation, and the elements are oriented to minimize changes in the net retardance vs. the input beam angle resulting from changes in the position and/or rotation of the system of elements.
    Type: Grant
    Filed: October 31, 2006
    Date of Patent: December 2, 2008
    Assignee: J.A. Woollam Co., Inc.
    Inventors: Blaine D. Johs, Steven E. Green, Craig M. Herzinger, Duane E. Meyer
  • Deviation angle self compensating substantially achromatic retarder
    Patent number: 7450231
    Abstract: A substantially achromatic multiple element compensator system for use in wide spectral range (for example, 190-1700 nm) rotating compensator spectroscopic ellipsometer and/or polarimeter systems. Multiple total internal reflections enter retardance into an entered beam of electromagnetic radiation, and the elements are oriented to minimize changes in the net retardance vs. the input beam angle resulting from changes in the position and/or rotation of the system of elements.
    Type: Grant
    Filed: December 4, 2006
    Date of Patent: November 11, 2008
    Assignee: J.A. Woollam Co., Inc.
    Inventors: Blaine D. Johs, Steven E. Green, Craig M. Herzinger, Duane E. Meyer
  • Reduced gas flow purging system in reflectometer, ellipsometer, polarimeter and the like systems
    Patent number: 7426030
    Abstract: Reflectometer, ellipsometer, polarimeter or the like system, which functionally comprise means for providing gas confined in a mini-chamber near the surface of a sample, at a location at which a beam having UV, VUV, IR and NIR wavelengths of electromagnetic radiation is caused to be impinged thereupon.
    Type: Grant
    Filed: February 10, 2007
    Date of Patent: September 16, 2008
    Assignee: J.A. Woollam Co., Inc.
    Inventors: Martin M. Liphardt, James D. Welch
  • Chain saw chain tensioning and braking system
    Patent number: 7412769
    Abstract: Disclosed is a chain saw which includes chain saw chain tensioning and braking systems. Tensioning and braking are effected by the presence and control of longitudinal slits in an elongated support which provides a continuous chain channel guide in its outer circumference.
    Type: Grant
    Filed: November 10, 2004
    Date of Patent: August 19, 2008
    Inventor: William C. King
  • System and method of selectively monitoring sample front and backside reflections in ellipsometer and the like systems
    Patent number: 7385698
    Abstract: A spectrophotometer, reflectometer, ellipsometer polarimeter or the like system having a detector means for independently intercepting electromagnetic radiation reflected from a sample frontside or backside, and methodology for pursuing less correlated determination of refractive index and thickness values.
    Type: Grant
    Filed: November 30, 2005
    Date of Patent: June 10, 2008
    Assignee: J.A. Woollam Co., Inc.
    Inventors: James D. Welch, John A. Woollam, Martin M. Liphardt
  • Sample analysis methodology utilizing electromagnetic radiation
    Patent number: 7385697
    Abstract: Simultaneous use of wavelengths in at least two ranges selected from RADIO, MICRO, FIR, IR, NIR-VIS-NUV, UV, DUV, VUV EUV, XRAY in a regression procedure to evaluate parameters in mathematical dispersion structures to model dielectric functions.
    Type: Grant
    Filed: May 20, 2004
    Date of Patent: June 10, 2008
    Assignee: J.A. Woollam Co., Inc.
    Inventors: John A. Woollam, Corey L. Bungay, Thomas E. Tiwald, Martin M. Liphardt, Ronald A. Synowicki, Gregory K. Pribil, Craig M. Herzinger, Blaine D. Johs, James N. Hilfiker
  • Drag race simulator
    Patent number: 7373888
    Abstract: A system which simulates a dragster which exposes a driver to both “G” forces and “wheelies”, and methodology of conducting a competition therewith.
    Type: Grant
    Filed: October 25, 2005
    Date of Patent: May 20, 2008
    Inventors: Kenneth D. Namanny, Keith E. Namanny, Kerry T. Namanny
  • Method of determining initial thickness value for sample surface layer, and use of splines for fitting ellipsometric data
    Patent number: 7362435
    Abstract: A method of determining a starting value for thickness of the most influential layer in a mathematical model of a sample for use in a data fitting routine, supplemented by the use of ordinary or B-spline polynomials to represent at least one of the real and imaginary parts of optical constants in the mathematical model.
    Type: Grant
    Filed: January 5, 2006
    Date of Patent: April 22, 2008
    Assignee: J.A. Wollam Co., Inc.
    Inventors: Blaine D. Johs, Jeffrey S. Hale
  • System for reducing stress induced effects during determination of fluid optical constants
    Patent number: 7349092
    Abstract: A system for determination of optical constants of liquids, including provision for reducing stress induced effects while obtaining data.
    Type: Grant
    Filed: October 24, 2005
    Date of Patent: March 25, 2008
    Assignee: J.A. Woollam Co., Inc
    Inventors: Thomas E. Tiwald, John A. Woollam, Galen L. Pfeiffer, Blaine D. Johs, Craig M. Herzinger
  • Control of beam spot size in ellipsometer and the like systems
    Patent number: 7345762
    Abstract: Disclosed are system for and method of analyzing substantially the exact same spot size on a sample system with at least two wavelengths for which the focal lengths do not vary more than within an acceptable amount.
    Type: Grant
    Filed: August 15, 2005
    Date of Patent: March 18, 2008
    Assignee: J.A. Woollam Co., Inc.
    Inventors: Martin M. Liphardt, Blaine D. Johs, John A. Woollam, Duane E. Meyer, James D. Welch
  • Spectroscopic ellipsometer and polarimeter systems
    Patent number: 7336361
    Abstract: A spectroscopic ellipsometer or polarimeter system having a source of a polychromatic beam of electromagnetic radiation, a polarizer, a stage for supporting a material system, an analyzer, a dispersive optics and a detector system which comprises a multiplicity of detector elements, there being apertures before the stage for supporting a material system, and thereafter, the system further having at least one multi-element lens and optionally being present in an environmental control chamber.
    Type: Grant
    Filed: October 25, 2005
    Date of Patent: February 26, 2008
    Assignee: J.A. Woollam Co., Inc.
    Inventors: Martin M. Liphardt, Blaine D. Johs, Jeffrey S. Hale, Craig M. Herzinger, Steven E. Green, Ping He, John A. Woollam
  • Sample orientation system and method
    Patent number: 7333198
    Abstract: Disclosed are systems and methodology for orienting the vertical position, and tilt, of samples, as applied in ellipsometer and the like systems.
    Type: Grant
    Filed: July 29, 2006
    Date of Patent: February 19, 2008
    Assignee: J.A. Woollam Co., Inc.
    Inventor: Martin M. Liphardt
  • Spectrophotometer, ellipsometer, polarimeter and the like systems
    Patent number: 7327456
    Abstract: Disclosed are improvements in ellipsometer and the like systems capable of operating in the Vacuum-Ultra-Violet (VUV) to Near Infrared (NIR) wavelength range, and methodology of use.
    Type: Grant
    Filed: June 6, 2005
    Date of Patent: February 5, 2008
    Assignee: J.A. Woollam Co., Inc.
    Inventors: John A. Woollam, Steven E. Green, Ping He, Blaine D. Johs, Craig M. Herzinger, Galen L. Pfeiffer, Brian D. Guenther, Martin M. Liphardt, Gerald T. Cooney
  • Aspects of producing, directing, conditioning, impinging and detecting spectroscopic electromagnetic radiation from small spots on samples
    Patent number: 7317529
    Abstract: Systems and methods for providing and enhancing electromagnetic radiation beam radial energy homogeneity and intensity vs. wavelength content, for reliably directing electromagnetic radiation emitted by a source thereof in a common direction, for achromatically reducing spot size on a sample (eg. liquid cavity containing lenses and low aberration 1:1 imaging systems modified to perform as spatial filters), and for directing different wavelengths into different detectors, in ellipsometer, polarizer or the like systems.
    Type: Grant
    Filed: August 27, 2004
    Date of Patent: January 8, 2008
    Assignee: J.A. Woollam Co., Inc.
    Inventors: Martin M. Liphardt, Ping He, Blaine D. Johs, Galen L. Pfeiffer, James D. Welch, John A. Woollam
  • Combined spatial filter and relay systems
    Patent number: 7317530
    Abstract: Low aberration relay systems modified to perform as spatial filters in reflectometer, spectrophotometer, ellipsometer, polarimeter and the like systems.
    Type: Grant
    Filed: March 22, 2005
    Date of Patent: January 8, 2008
    Assignee: J.A. Woollam Co., Inc.
    Inventors: Martin M. Liphardt, Ping He
  • Method of reducing the effect of noise in determining the value of a dependent variable
    Patent number: 7307724
    Abstract: A method of reducing the effect of systematic and/or random noise during determination of dependent variable values, (eg. pseudo “n” and “k” and/or ellipsometric PSI and DELTA or mathematical equivalent vs. wavelength or angle of incidence), involving selecting a mathematical function and an independent variable subset range combination so that a square error best fit with total summed square error over the independent variable subset range being minimized, zero or within an acceptable range near zero, are achieved.
    Type: Grant
    Filed: March 5, 2004
    Date of Patent: December 11, 2007
    Assignee: J.A. Woollam Co., Inc.
    Inventors: Martin M. Liphardt, Blaine D. Johs