Patents by Inventor Lennart Ramberg

Lennart Ramberg 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: 6104043
    Abstract: A Schottky diode of SiC has a substrate layer, a drift layer and emitter layer regions formed in the drift layer. A metal layer makes an ohmic contact to the emitter layer regions and Schottky contact to the drift layer. A depletion of the drift layer region between two adjacent emitter layer regions is allowed in the blocking state of the diode making the two adjacent p-type emitter layer regions form a continuous depleted region therebetween in this state.
    Type: Grant
    Filed: February 20, 1997
    Date of Patent: August 15, 2000
    Assignee: ABB Research Ltd.
    Inventors: Willy Hermansson, Bo Bijlenga, Lennart Ramberg, Kurt Rottner, Lennart Zdansky, Christopher Ian Harris, Mietek Bakowski, Adolf Schoner, Nils Lundberg, Mikael Ostling, Fanny Dahlquist
  • Patent number: 5914499
    Abstract: The invention relates to a method in which proton or ion implantation is used for restructuring a silicon carbide region from being conductive to being resistive and wherein this implantation method is used for manufacturing a semiconductor device which comprises a p-n junction where both the p-conductive and the n-conductive layers are designed as doped layers of silicon carbide (SiC), whereby the implantation method is used for at least one of the steps passivation of a silicon carbide surface of the device with a semi-insulating layer, definition of the area of the p-n junction during manufacture, termination of the edges of the p-n junction by means of a semi-insulating layer, creation of a positive edge angle at the edge of the p-n junction, and insulation of different devices from one another during manufacture of a plurality of devices on one and the same wafer of silicon carbide, wherein the invention also relates to the implantation method proper.
    Type: Grant
    Filed: March 5, 1997
    Date of Patent: June 22, 1999
    Assignee: ABB Research Ltd.
    Inventors: Willy Hermansson, Lennart Ramberg, Dag Sigurd