Patents by Inventor Heinrich Hennhofer

Heinrich Hennhofer 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).

  • Patent number: 6530826
    Abstract: A process for the surface polishing of a silicon wafer, includes the successive polishing of the silicon wafer on at least two different polishing plates covered with polishing cloth, with a continuous supply of alkaline polishing abrasive with SiO2 constituents, an amount of silicon removed during the polishing on a first polishing plate being significantly higher than on a second polishing plate, with the overall amount of silicon removed not exceeding 1.5 &mgr;m. A polishing abrasive (1a), then a mixture of a polishing abrasive (1b) and at least one alcohol, and finally ultrapure water (1c) are added to the first polishing plate, and a mixture of a polishing abrasive (2a) and at least one alcohol and then ultrapure water (2b) are added to the second plate.
    Type: Grant
    Filed: October 30, 2001
    Date of Patent: March 11, 2003
    Assignee: Wacker Siltronic Gesellschaft für Halbleitermaterialien AG
    Inventors: Guido Wenski, Thomas Buschhardt, Heinrich Hennhöfer, Bruno Lichtenegger
  • Publication number: 20020187639
    Abstract: A process is provided for treating a polished semiconductor wafer immediately after the semiconductor wafer has been polished. The semiconductor wafer is brought into contact with an aqueous treatment agent solution and its polished surface is oxidized by the action of the aqueous treatment agent solution.
    Type: Application
    Filed: February 27, 1998
    Publication date: December 12, 2002
    Inventors: HEINRICH HENNHOFER, THOMAS BUSCHHARDT, FRANZ MANGS, GERLINDE WENSAUER
  • Publication number: 20020077039
    Abstract: A process for the surface polishing of a silicon wafer, includes the successive polishing of the silicon wafer on at least two different polishing plates covered with polishing cloth, with a continuous supply of alkaline polishing abrasive with SiO2 constituents, an amount of silicon removed during the polishing on a first polishing plate being significantly higher than on a second polishing plate, with the overall amount of silicon removed not exceeding 1.5 &mgr;m. A polishing abrasive (1a), then a mixture of a polishing abrasive (1b) and at least one alcohol, and finally ultrapure water (1c) are added to the first polishing plate, and a mixture of a polishing abrasive (2a) and at least one alcohol and then ultrapure water (2b) are added to the second plate.
    Type: Application
    Filed: October 30, 2001
    Publication date: June 20, 2002
    Applicant: WACKER, SILTRONIC GESELLSCHAFT FUR HALBLEITERMATERIALIEN AG
    Inventors: Guido Wenski, Thomas Buschhardt, Heinrich Hennhofer, Bruno Lichtenegger
  • Patent number: 6095898
    Abstract: A process and device for polishing semiconductor wafers has at least one side of at least one semiconductor wafer pressed against a polishing plate, over which a polishing cloth is stretched. The semiconductor wafer and the polishing plate are moved relative to each other to polish the wafer. During the polishing, the semiconductor wafer passes over at least two regions on the polishing plate, which regions have defined radial widths and are at different temperatures. Temperature-control means are provided in the polishing plate, with the aid of which the number, the radial widths and the temperatures of the regions are fixed before the semiconductor wafers are polished.
    Type: Grant
    Filed: October 28, 1998
    Date of Patent: August 1, 2000
    Assignee: Wacker Siltronic Gesellschaft fur Halbleitermaterialien AG
    Inventors: Heinrich Hennhofer, Hans Kramer, Helmut Kirschner, Manfred Thurner, Thomas Buschhardt, Klaus Rottger
  • Patent number: 5980361
    Abstract: A method is for the polishing of semiconductor wafers, which are mounted on a front side of a support plate and one side face of which is pressed anst a polishing plate, which is covered with a polishing cloth, with a specific polishing pressure and polished. A device is provided which is suitable for carrying out the method. The method includes a) applying a specific pressure to at least one of a plurality of pressure chambers prior to the polishing of the semiconductor wafers, and b) during the polishing of the semiconductor wafers, transmitting the polishing pressure to a rear side of the support plate via elastic bearing surfaces of the pressure chambers to which pressure has been applied.
    Type: Grant
    Filed: December 9, 1997
    Date of Patent: November 9, 1999
    Assignee: Wacker Siltronic Gesellschaft fur Halbleitermaterialien AG
    Inventors: Paul Muller, Thomas Buschhardt, Heinrich Hennhofer, Norbert Sickmann, Rainer Neumann, Franz Mangs, Manfred Thurner, Klaus Rottger