Patents Assigned to Hahn-Meitner-Institut fur Kernforschung Berlin GmbH
  • Patent number: 4704576
    Abstract: Variations in parameters of a waveguide system caused by an excitation of charge carriers of a specimen to be measured and positioned in a microwave field, give definite information on the material properties of the specimen without having to destroy, or even contact the specimen. Irradiation with a sharply focused photon or electron beam of a surface spot having a diameter of about 0.1 to 10.0 micrometers, and displacing of this light spot across the surface of the specimen, with the displacement increments of the specimen within the cross sectional area of a waveguide being of the order of magnitude of micrometers, surface structures such as ground boundaries, steps in stratified-lattice crystals, formation defects, destroyed surface areas, etc., can be detected in photosensitive semiconductor layers with a high resolution.
    Type: Grant
    Filed: February 28, 1985
    Date of Patent: November 3, 1987
    Assignee: Hahn-Meitner-Institut fur Kernforschung Berlin GmbH
    Inventors: Helmut Tributsch, Gerhard Beck, Marinus Kunst
  • Patent number: 4700311
    Abstract: Materials and systems substantially having photoactive properties are produced with a high quality output and without time losses in the fabrication process. To determine the quality of the photoactive material in situ, conductivity is induced in the material by exciting charge carriers through irradiation, and an electromagnetic field influenced thereby is measured, with the result of the measurement being evaluated by a computer with a corresponding control of actuating members such as valves and controllers. Optimum process parameters are thus found and used for the process.
    Type: Grant
    Filed: January 25, 1985
    Date of Patent: October 13, 1987
    Assignee: Hahn-Meitner-Institut fur Kernforschung Berlin GmbH
    Inventors: Helmut Tributsch, Gerhard Beck, Marinus Kunst, Udo Kuppers, Hans-Joachim Lewerenz, Jochen Lilie, Andre Werner
  • Patent number: 4663830
    Abstract: A buried grid structure is produced in a semiconductor material particularly a silicon wafer, while using a metallic grid mask. The buried grid is formed directly within the semiconductor material by contradoping ion implantation by means of a high energy accelerator through the metallic grid mask. The bars or ribs of the metallic grid mask stop the ions passing therethrough so that two vertically separated and laterally offset buried grid structures are produced. By beveling the periphery of the wafer, buried conductive structures are formed at the same time as connections between the buried grid structures and a control electrode provided on the back side of the wafer.
    Type: Grant
    Filed: February 7, 1985
    Date of Patent: May 12, 1987
    Assignee: Hahn-Meitner-Institut fur Kernforschung Berlin GmbH
    Inventors: Dietrich Braunig, Meinhard Knoll, Joachim Laschinski, Wolfgang Fahrner
  • Patent number: 4601960
    Abstract: To obtain an efficiency of about 10% in photoelectrochemical solar cells, the pairing of semiconductor material for the working electrode and composition of the electrolyte liquid is of critical importance. The semiconductor material therefore should not be too expensive, and should have a short absorption length for light and be resistant to photocorrosion. Further, a non-toxic electrolyte should be employed permitting operation even without a hermetic seal. The photoelectrochemical solar cell of the invention utilizes a CuInSe.sub.2 or CuInS.sub.2 in a ternary compound, for the semiconductor material, which is used with an iodine-iodide solution as an electrolyte. In a method of fabricating a substrate for such a cell, a surface film is produced on a single-crystal or polycrystalline semiconductor material, particularly CuInSe.sub.
    Type: Grant
    Filed: August 6, 1984
    Date of Patent: July 22, 1986
    Assignee: Hahn-Meitner-Institut fur Kernforschung Berlin GmbH
    Inventors: Shalini Menezes, Hans-Joachim Lewerenz, Klaus Bachmann
  • Patent number: 4547679
    Abstract: A generator for producing high-voltage rectangular pulses is provided which comprises devices for conversion of input power supplied from a DC source into pulses of output power using capacitive storage units, a pulser head for the connection of a coaxial cable leading to a load and a gas-filled pulser tube.
    Type: Grant
    Filed: April 8, 1983
    Date of Patent: October 15, 1985
    Assignee: Hahn-Meitner-Institut fur Kernforschung Berlin GmbH
    Inventors: Diethard Hansen, Martin Wilhelm
  • Patent number: 4032477
    Abstract: An enhanced electron yield is obtained during irradiation of a sensibilizer with light in the presence of water when a hydrophobic organic material is present as a separate phase having an electron repelling surface in contact with the water and containing the sensibilizer.
    Type: Grant
    Filed: March 18, 1976
    Date of Patent: June 28, 1977
    Assignee: Hahn-Meitner-Institut fur Kernforschung Berlin GmbH
    Inventor: Michael Gratzel
  • Patent number: 3932225
    Abstract: Spent reactor fuel elements are dissolved in dilute nitric acid. After addition of acetic acid as a complexing agent, the nitric acid is partly decomposed and the mixture subjected to electrolysis while a carrier liquid, which may be dilute acetic acid or a dilute mixture of acetic acid and nitric acid is caused to flow in the electric field between the electrodes either against the direction of ion migration or transversely thereto. The ions of uranium, plutonium and other transuranium elements, and of fission products accumulate in discrete portions of the electrolyte and are separately withdrawn as at least three fractions after one or more stages of electrolysis.
    Type: Grant
    Filed: November 3, 1972
    Date of Patent: January 13, 1976
    Assignee: Hahn-Meitner-Institut fur Kernforschung Berlin GmbH
    Inventors: Abdel-Lativ Bilal, Klaus Metscher, Bernhard Muhlig, Christoph Reichmuth, Bernd Schwarz, Karl-Erik Zimen