Patents by Inventor Kati Hemmann

Kati Hemmann 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: 8395244
    Abstract: A fast recovery diode includes an n-doped base layer having a cathode side and an anode side opposite the cathode side. A p-doped anode layer is arranged on the anode side. The anode layer has a doping profile and includes at least two sublayers. A first one of the sublayers has a first maximum doping concentration, which is between 2*1016 cm?3 and 2*1017 cm?3 and which is higher than the maximum doping concentration of any other sublayer. A last one of the sublayers has a last sublayer depth, which is larger than any other sublayer depth. The last sublayer depth is between 90 to 120 ?m. The doping profile of the anode layer declines such that a doping concentration in a range of 5*1014 cm?3 and 1*1015 cm?3 is reached between a first depth, which is at least 20 ?m, and a second depth, which is at maximum 50 ?m. Such a profile of the doping concentration is achieved by using aluminum diffused layers as the at least two sublayers.
    Type: Grant
    Filed: November 9, 2010
    Date of Patent: March 12, 2013
    Assignee: ABB Technology AG
    Inventors: Jan Vobecky, Kati Hemmann, Hamit Duran, Munaf Rahimo
  • Publication number: 20110108953
    Abstract: A fast recovery diode includes an n-doped base layer having a cathode side and an anode side opposite the cathode side. A p-doped anode layer is arranged on the anode side. The anode layer has a doping profile and includes at least two sublayers. A first one of the sublayers has a first maximum doping concentration, which is between 2*1016 cm?3 and 2*1017 cm?3 and which is higher than the maximum doping concentration of any other sublayer. A last one of the sublayers has a last sublayer depth, which is larger than any other sublayer depth. The last sublayer depth is between 90 to 120 ?m. The doping profile of the anode layer declines such that a doping concentration in a range of 5*1014 cm?3 and 1*1015 cm?3 is reached between a first depth, which is at least 20 ?m, and a second depth, which is at maximum 50 ?m. Such a profile of the doping concentration is achieved by using aluminium diffused layers as the at least two sublayers.
    Type: Application
    Filed: November 9, 2010
    Publication date: May 12, 2011
    Applicant: ABB Technology AG
    Inventors: Jan VOBECKY, Kati Hemmann, Hamit Duran, Munaf Rahimo