Patents by Inventor Helmut Kirschner

Helmut Kirschner 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: 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: 5049200
    Abstract: Silicon wafers can be provided with a hydrophilic surface and/or freed of hering cement residues originating from the polishing operation with the aid of solutions adjusted to a pH of 8 to 14 with the aid of alkali-metal or alkaline-earth-metal compounds and containing hydrogen peroxide. These processes can even be carried out at room temperature and are remarkable for their low chemical consumption and easy manageability.
    Type: Grant
    Filed: October 5, 1988
    Date of Patent: September 17, 1991
    Assignee: Wacker-Chemitronic Gesellschaft fur Elektronik-Grundstoffe mbH
    Inventors: Roland Brunner, Susanne Bauer-Mayer, Rudolf Griesshammer, Helmut Kirschner
  • Patent number: 4114175
    Abstract: The shutter mechanism includes an aperture-unblocking member mounted for movement between an unactivated aperture-blocking position and an activated aperture-unblocking position. A cocked drive mechanism is coupled to the aperture-unblocking member and is operative when released for moving the member from the unactivated to the activated position. An inertial braking mechanism is driven by the drive mechanism when the latter moves the aperture-unblocking member to the activated position, and is operative during such movement for applying to the drive mechanism an inertial braking force slowing the movement of the aperture-unblocking member to the activated position. The drive mechanism includes a drive cam, and the inertial braking mechanism includes a driven cam. The surface of the drive cam bears upon the surface of the driven cam and transmits to the driven cam the drive force by means of which the drive mechanism drives the inertial braking mechanism.
    Type: Grant
    Filed: January 28, 1977
    Date of Patent: September 12, 1978
    Assignee: Agfa-Gevaert AG
    Inventors: Leonhard Huber, Helmut Kirschner, Herbert Muller
  • Patent number: 4070797
    Abstract: Process for making haze-free surfaces of semiconductor bodies which comprs a first step of polishing the surface by means of a polishing agent containing at least one member of the group consisting of quartz, silica, silicates and fluosilicates, and a second step of polishing the surface by means of a polishing agent containing in addition to the above defined agents from 0.1 to 10% by weight calculated on the polishing agent of a nitrogen-free surfactant selected from the group consisting of anionic and non-ionic surfactants, and a mixture thereof.
    Type: Grant
    Filed: July 2, 1976
    Date of Patent: January 31, 1978
    Assignee: Wacker-Chemitronic Gesellshaft fur Elektronic Grundstoffe mbH
    Inventors: Rudolf Griesshammer, Helmut Kirschner, Gunther Lechner
  • Patent number: 4057142
    Abstract: A stackable plastics pallet for packaging semiconductor discs on a gas-ti foil covering, said pallet having a plurality of circular depressions each for accommodating a semiconductor disc, and means for securing the discs between the pallets, the securing means being in the form of sloping part-sector shaped surfaces surrounding said depressions, with two opposite sets of sloping surfaces clamping the semiconductor discs at their outermost rims and immobilizing them thereby.
    Type: Grant
    Filed: July 26, 1976
    Date of Patent: November 8, 1977
    Assignee: Wacker-Chemitronic Gesellschaft fur Elektronik-Grundstoffe mbH
    Inventors: Gunther Lechner, Karl Pritscher, Helmut Kirschner
  • Patent number: 4042419
    Abstract: Process of the removal of point defects and point defect agglomerates from emiconductor discs, which comprises the steps of providing one side of the discs with a mechanical stress field and then subjecting the discs to a heat treatment.
    Type: Grant
    Filed: July 23, 1976
    Date of Patent: August 16, 1977
    Assignee: Wacker-Chemitronic Gesellschaft fur Elektronik-Grundstoffe mbH
    Inventors: Wolfgang Heinke, Helmut Kirschner, Detlef Reimann