Patents by Inventor Henry K. Chau

Henry K. Chau 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).

  • Publication number: 20030124028
    Abstract: The invention provides methods, apparatus, and systems for performing high-throughput preparation and screening of salts and polymorphs of drug candidates. The invention is directed towards enhancing the pre-formulation discovery process used for drug development. In particular, processes that determine suitable salts and processes that discover substantially every polymorph that can form from a particular drug candidate are provided. The processes are performed using several apparatuses that are specifically configured to carry-out various steps in a high-throughput characterization process. One such apparatus is configured for synthesizing a plurality of library members based on, for example, a library model generated by a computer system. Another apparatus may filter the synthesized solution to provide a substantially pure mixture that can be subjected to salt or polymorph testing.
    Type: Application
    Filed: May 24, 2002
    Publication date: July 3, 2003
    Inventors: Eric D. Carlson, Peijun Cong, William H. Chandler, Henry K. Chau, Earl Danielson, Peter J. Desrosiers, Robert D. Doolen, Luping Wu, C. Eric Ramberg, Thomas Crevier, Ralph B. Nielsen, Colin S. Masui, John F. Varni
  • Patent number: 5936254
    Abstract: A method and apparatus for detecting the presence of a thin film such as a photoresist film on a semiconductor wafer or other substrate. Only when a film is present does the surface reflectance (reflective power) of light incident on the wafer surface vary sinusoidally when the incidence angle of the light is varied. This sinusoidal variation in the reflected optical power is due to interference occurring between the film surface and wafer surface reflections. This method and apparatus allows determining whether an undeveloped photoresist layer is present on a wafer; this is not possible using merely visual inspection especially when an underlying pattern is present. The present method and apparatus may also be used to determine the thickness of a particular thin film.
    Type: Grant
    Filed: March 11, 1997
    Date of Patent: August 10, 1999
    Assignee: Nikon Research Corporation of America
    Inventors: Arun A. Aiyer, John H. McCoy, Henry K. Chau
  • Patent number: 5859698
    Abstract: Macro defects in a processed or partly processed semiconductor wafer, liquid crystal display element, disk drive element or the like, are detected using scattered light. By use of automated image processing techniques, a reference image and a sample image are formed from the scattered light and edge enhanced. A difference image is formed by comparing the edge enhanced reference and sample images. The difference image is evaluated using one or more automated image processing techniques such as thresholding, morphological transformations and blob analysis to identify macro defects.
    Type: Grant
    Filed: May 7, 1997
    Date of Patent: January 12, 1999
    Assignee: Nikon Corporation
    Inventors: Henry K. Chau, Arun A. Aiyer
  • Patent number: 5838448
    Abstract: A chemical-mechanical polishing (CMP) optical process monitor apparatus allows in situ measurement of the thickness of a thin film being polished. As the incidence angle of the incident light on the wafer being polished is changed, the reflected intensity of the light from the thin film on the wafer undergoes a variation in local maxima and minima. The angle at which the light intensity is a maximum or minimum determined by the thin film interference equation, thus providing a measurement of the thin film thickness and/or the change in the thin film thickness.
    Type: Grant
    Filed: March 11, 1997
    Date of Patent: November 17, 1998
    Assignee: Nikon Corporation
    Inventors: Arun A. Aiyer, Paul Derek Coon, Henry K. Chau
  • Patent number: 5777729
    Abstract: Defects in a processed or partly processed semiconductor wafer, or other similar three-dimensional periodic pattern formed on a substrate surface, are detected by light diffraction. Incident monochromatic light is provided from an elongated and extended source to illuminate the entire wafer surface. By use of automated image processing techniques, wafer macro inspection is thereby automated. The elongated and extended light source allows light at different angles to be incident upon each point of the wafer surface, thereby allowing defect detection for an entire wafer surface in a single field of view and reducing inspection time. The particular wavelength of the incident monochromatic light is predetermined to allow optimum detection of defects in the periodic pattern on the wafer, depending on the width and pitch of the features of the periodic pattern.
    Type: Grant
    Filed: May 7, 1996
    Date of Patent: July 7, 1998
    Assignee: Nikon Corporation
    Inventors: Arun A. Aiyer, John H. McCoy, Kyoichi Suwa, Henry K. Chau