Patents by Inventor Hans-Joachim Wurfl

Hans-Joachim Wurfl 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).

  • Publication number: 20230420542
    Abstract: The invention relates to a method for producing a transistor with a high degree of electron mobility and to a transistor with a high degree of electron mobility. The method is characterized in that an epitaxial layer is first grown on a flat substrate, and the flat substrate is then completely removed from the bottom of the epitaxial layer, wherein a thermally conductive layer is applied onto the bottom of the epitaxial layer such that the thermally conductive layer contacts at least 80%, preferably at least 90%, particularly preferably at least 95%, in particular 100%, of the bottom of the epitaxial layer. The method is simple and inexpensive to carry out and provides a transistor which has a high degree of electron mobility, an improved electric output without backgating, and an improved heat dissipation. The method additionally allows a transistor to be provided with a vertical transistor structure.
    Type: Application
    Filed: November 25, 2021
    Publication date: December 28, 2023
    Applicants: FRAUNHOFER-GESELLSCHAFT ZUR FÖRDERUNG DER ANGEWANDTEN FORSCHUNG E.V., FERDINAND-BRAUN-INSTITUT GGMBH, LEIBNIZ-INSTITUT FÜR HÖCHSTFREQUENZTECHNIK
    Inventors: Elke MEISSNER, Hans-Joachim WÜRFL
  • Patent number: 11127863
    Abstract: This invention concerns a gate structure and a process for its manufacturing. In particular, the present invention concerns the gate structuring of a field effect transistor with reduced thermo-mechanical stress and increased reliability (lower electromigration or diffusion of the gate metal). The gate structure according to the invention comprises a substrate; an active layer disposed on the substrate; an intermediate layer disposed on the active layer, the intermediate layer-having a recess extending through the entire intermediate layer towards the active layer; and a contact element which is arranged within the recess, the contact element completely filling the recess and extending to above the intermediate layer, the contact element resting at least in sections directly on the intermediate layer; the contact element being made of a Schottky metal and the contact element having an interior cavity completely enclosed by the Schottky metal.
    Type: Grant
    Filed: November 20, 2017
    Date of Patent: September 21, 2021
    Assignee: FORSCHUNGSVERBUND BERLIN E.V.
    Inventors: Konstantin Osipov, Richard Lossy, Hans-Joachim Würfl
  • Publication number: 20200066919
    Abstract: This invention concerns a gate structure and a process for manufacturing. In particular, the present invention concerns the gate structuring of a field effect transistor with reduced thereto-mechanical stress and increased reliability (lower electromigration or diffusion of the gate metal).
    Type: Application
    Filed: November 20, 2017
    Publication date: February 27, 2020
    Inventors: Konstantin OSIPOV, Richard LOSSY, Hans-Joachim WÜRFL
  • Patent number: 9431557
    Abstract: The present invention relates to a UV photodetector having a high sensitivity and a low dark current. The object of the present invention is to specify a UV photodetector that has a high sensitivity and a low dark current. According to the invention, the fingers of the first electrode structure and the fingers of the second electrode structure have a cover layer made of a second semiconducting material, wherein the cover layer is arranged on the absorber layer and directly contacts the absorber layer in the region of the fingers, and the first semiconducting material and the second semiconducting material are designed in such a manner that a two-dimensional electron gas (2DEG) is formed at the boundary layer between the absorber layer and the cover layer in the region of the fingers.
    Type: Grant
    Filed: April 26, 2012
    Date of Patent: August 30, 2016
    Assignee: Forschungsverbung Berlin E.V.
    Inventors: Andrea Knigge, Markus Weyers, Hans-Joachim Wurfl
  • Patent number: 8809968
    Abstract: This invention relates to a semiconductor layer structure. The semiconductor layer structure described includes a substrate and a buffer layer deposited onto the substrate. The semiconductor layer structure is characterized in that a drain voltage threshold lower than the breakdown voltage threshold is determined by isolating ions that are selectively implanted in just one region of the substrate into the substrate, wherein charge can dissipate from the one contact through the buffer layer towards a substrate region without isolating ions, if the one potential deviates from the other at least by the drain voltage threshold, and wherein the substrate region without isolating ions is located underneath the one contact. The semiconductor layer structure described allows dissipation of currents induced by induction in blocking active structures without damaging the active structures.
    Type: Grant
    Filed: May 7, 2013
    Date of Patent: August 19, 2014
    Assignee: Forschungsverbund Berlin E.V.
    Inventors: Oliver Hilt, Rimma Zhytnytska, Hans-Joachim Würfl
  • Publication number: 20140070272
    Abstract: The present invention relates to a UV photodetector having a high sensitivity and a low dark current. The object of the present invention is to specify a UV photodetector that has a high sensitivity and a low dark current. According to the invention, the fingers of the first electrode structure and the fingers of the second electrode structure have a cover layer made of a second semiconducting material, wherein the cover layer is arranged on the absorber layer and directly contacts the absorber layer in the region of the fingers, and the first semiconducting material and the second semiconducting material are designed in such a manner that a two-dimensional electron gas (2DEG) is formed at the boundary layer between the absorber layer and the cover layer in the region of the fingers.
    Type: Application
    Filed: April 26, 2012
    Publication date: March 13, 2014
    Applicant: Forschungsverbund Berlin e.V.
    Inventors: Andrea Knigge, Markus Weyers, Hans-Joachim Wurfl
  • Publication number: 20130240894
    Abstract: An overvoltage protection device for compound semiconductor field effect transistors includes an implanted region disposed in a compound semiconductor material. The implanted region has spatially distributed trap states which cause the implanted region to become electrically conductive at a threshold voltage. A first contact is connected to the implanted region. A second contact spaced apart from the first contact is also connected to the implanted region. The distance between the first and second contacts partly determines the threshold voltage of the overvoltage protection device.
    Type: Application
    Filed: March 13, 2012
    Publication date: September 19, 2013
    Inventors: Hans Joachim Würfl, Eldad Bahat-Treidel, Chia-Ta Chang, Oliver Hilt, Rimma Zhytnytska
  • Publication number: 20130241006
    Abstract: This invention relates to a semiconductor layer structure. The semiconductor layer structure described includes a substrate and a buffer layer deposited onto the substrate. The semiconductor layer structure is characterized in that a drain voltage threshold lower than the breakdown voltage threshold is determined by isolating ions that are selectively implanted in just one region of the substrate into the substrate, wherein charge can dissipate from the one contact through the buffer layer towards a substrate region without isolating ions, if the one potential deviates from the other at least by the drain voltage threshold, and wherein the substrate region without isolating ions is located underneath the one contact. The semiconductor layer structure described allows dissipation of currents induced by induction in blocking active structures without damaging the active structures.
    Type: Application
    Filed: May 7, 2013
    Publication date: September 19, 2013
    Applicant: Forschungsverbund Berlin E.V.
    Inventors: Oliver HILT, Rimma ZHYTNYTSKA, Hans-Joachim WÜRFL