Patents by Inventor Dieter Helmreich

Dieter Helmreich 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: 6362487
    Abstract: The nondestructive detection and characterization of crystal defects in monocrystalline semiconductor material is by a combination of photoluminescence heterodyne spectroscopy, photothermal heterodyne spectroscopy and SIRD.
    Type: Grant
    Filed: May 25, 1999
    Date of Patent: March 26, 2002
    Assignee: Wacker Siltronic Gesellschaft für Halbleitermaterialien AG
    Inventors: Andreas Ehlert, Michael Kerstan, Holger Lundt, Dieter Helmreich
  • Patent number: 4769107
    Abstract: A process and apparatus for the manufacture of silicon blocks having a columnar structure comprising monocrystalline crystal zones having a crystallographic preferred orientation. In a casting process, each mold filled with molten silicon is transferred, before the silicon has solidified completely, to a separate crystallization station where the silicon can then crystallize completely. During this process, the exposed surface of the silicon is maintained in a molten state until the end of the solidification process has almost been reached. The process allows the various, necessary steps to be carried out simultaneously and yields high-quality solar cell base material.
    Type: Grant
    Filed: June 26, 1985
    Date of Patent: September 6, 1988
    Assignee: Heliotronic Forschungs- und Entwicklungsgesellschaft fur Solarzellen-Grundstoffe mbH
    Inventors: Dieter Helmreich, Cord Gessert, Hans-Dieter Miller, Helmut Zauhar, Georg Priewasser, Leonhard Schmidhammer
  • Patent number: 4447289
    Abstract: The invention provides a process for the manufacture of coarsely crystalline to monocrystalline sheets and/or plates of semiconductor material of preferred orientation. A meniscus of molten semiconductor material comes in contact with a moving, cooler substrate of the same coarsely crystalline to monocrystalline semiconductor material, during which, while transferring the preferred orientation, a thin sheet of the semiconductor material is pulled onto the substrate and, after cooling, becomes detached from the substrate. The substrate can be reused as often as desired.
    Type: Grant
    Filed: July 12, 1982
    Date of Patent: May 8, 1984
    Assignee: Heliotronic Forschungs-und Entwicklungsgesellschaft fur Solarzellen-Grundstoffe mbH
    Inventors: Joachim Geissler, Dieter Helmreich
  • Patent number: 4366024
    Abstract: Competitive current generation by the exploitation of solar energy requires cheap solar cells. A process is described which makes it possible to manufacture from silicon a base material for solar cells of this type in an economical manner and in large quantities. This is achieved by bringing silicon from a supply container into contact with a non-elemental lubricating melt, which is immiscible with silicon but will not wet silicon and has a melting point below that of silicon, and by drawing off a silicon film, sliding on this lubricating melt, and solidifying the silicon continuously by cooling to below its' melting point.
    Type: Grant
    Filed: January 25, 1980
    Date of Patent: December 28, 1982
    Assignee: Heliotronic Forschungs-und Entwicklungsgesellschaft fur Solarzellen-Grundstoffe mbH
    Inventors: Gerhard Ast, Josef Dietl, Dieter Helmreich, Hans-Dieter Miller, Erhard Sirtl
  • Patent number: 4312700
    Abstract: To make solar energy competitive, as compared against other sources of energy, inexpensive solar cells are required. To accomplish this goal, a method is provided which enables one to produce silicon rods having a columnar structure made of monocrystalline zones with preferential crystallographic orientation. This is effected by feeding a silicon melt into a crystallization chamber having a vertically movable cooled bottom face under the influence of a temperature gradient directed parallel to the rod axis, so that the rods can be made continuously or semicontinuously with high drawing speeds.
    Type: Grant
    Filed: June 9, 1980
    Date of Patent: January 26, 1982
    Assignee: Helictronic Forschungs- und Entwicklungs- Gesellschaft fur Solarzellen-Grundstoffe mbH
    Inventors: Dieter Helmreich, Erhard Sirtl, Theo Zollner