Patents by Inventor Hajo van der Muehlen

Hajo van der Muehlen 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).

  • Wafer orientation sensor for GaAs wafers
    Patent number: 6489626
    Abstract: A wafer oriented includes a mechanism for rotating a wafer and a wafer orientation sensor. The wafer orientation sensor includes a light source for emitting light, a light sensor for sensing the light emitted by the light source as an edge of the wafer is rotated between the light source and the sensor and for producing a sensor signal representative of the sensed light, and an optical filter positioned between the light source and the light sensor. The optical filter has a light-transmission characteristic wherein light in the pass band of the wafer is blocked. When the wafer orientation sensor is used for sensing gallium arsenide wafers, the optical filter is selected to block light at wavelengths greater than about 860 nanometers.
    Type: Grant
    Filed: July 27, 2001
    Date of Patent: December 3, 2002
    Assignee: Varian Semiconductor Equipment Associates, Inc.
    Inventors: Hajo van der Muehlen, Peter Bruno Mouttet, Bernhard Boche
  • Wafer orientation sensor for GaAs wafers
    Publication number: 20010042845
    Abstract: A wafer orienter includes a mechanism for rotating a wafer and a wafer orientation sensor. The wafer orientation sensor includes a light source for emitting light, a light sensor for sensing the light emitted by the light source as an edge of the wafer is rotated between the light source and the sensor and for producing a sensor signal representative of the sensed light, and an optical filter positioned between the light source and the light sensor. The optical filter has a light-transmission characteristic wherein light in the pass band of the wafer is blocked. When the wafer orientation sensor is used for sensing gallium arsenide wafers, the optical filter is selected to block light at wavelengths greater than about 860 nanometers.
    Type: Application
    Filed: July 27, 2001
    Publication date: November 22, 2001
    Applicant: Varian Semiconductor Equipment Associates, Inc.
    Inventors: Hajo van der Muehlen, Peter Bruno Mouttet, Bernhard Boche