Search Patents
  • Patent number: 6521917
    Abstract: A group III-nitride quaternary material system and method is disclosed for use in semiconductor structures, including laser diodes, transistors, and photodetectors, which reduces or eliminates phase separation and provides increased emission efficiency. In an exemplary embodiment the semiconductor structure includes a first InGaAlN layer of a first conduction type formed substantially without phase separation, an InGaAlN active layer substantially without phase separation, and a third InGaAlN layer of an opposite conduction type formed substantially without phase separation.
    Type: Grant
    Filed: March 26, 1999
    Date of Patent: February 18, 2003
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Toru Takayama, Takaaki Baba, James S. Harris, Jr.
  • Patent number: 6229150
    Abstract: A group III-nitride quatenary material system and method is disclosed for use in semiconductor structures, including laser diodes, transistors, and photodetectors, which reduces or eliminates phase separation and provides increased emission efficiency and reliability. In an exemplary embodiment the semiconductor structure includes first GaAINAs layer of a first conduction type formed substantially without phase separation, an GaAINAs active layer substantially without phase separation, and a third GaAINAs layer of an opposite conduction type formed substantially without phase separation.
    Type: Grant
    Filed: July 30, 1999
    Date of Patent: May 8, 2001
    Assignee: Matsushita Electronics Corp.
    Inventors: Toru Takayama, Takaaki Baba, James S. Harris, Jr.
  • Patent number: 5270798
    Abstract: A high-electron mobility transistor or HEMT has a top surface layer between its gate and drain arranged to produce a channel to drain conductance that is close to the ungated channel conductance to lower the output conductance and reduce gate leakage and gate capacitance. The transistor has a high band-gap active layer to produce a 2DEG channel in an adjacent layer, and source, gate and drain electrodes on the active layer. An undoped or lightly doped surface layer in the region between the gate and the drain produces a low conductance for a region of a few hundred .ANG. from the drain-side edge of the gate. This spreads the electric field domain over at least this few hundred .ANG. distance.
    Type: Grant
    Filed: February 20, 1990
    Date of Patent: December 14, 1993
    Assignee: Varian Associates, Inc.
    Inventors: Yi-Ching Pao, James S. Harris
  • Patent number: 6472680
    Abstract: Group III-nitride quaternary and pentenary material systems and methods are disclosed for use in semiconductor structures, including laser diodes, transistors, and photodetectors, which reduce or eliminate phase separation and provide increased emission efficiency. In an exemplary embodiment the semiconductor structure includes a first ternary, quaternary or pentenary material layer using an InGaAlNAs material system of a first conduction type formed substantially without phase separation, a quaternary or pentenary material active layer using an InGaAlNAs material system substantially without phase separation, and a third ternary, quaternay or pentenary an InGaAlNAs material system of an opposite conduction type formed substantially without phase separation.
    Type: Grant
    Filed: December 31, 1999
    Date of Patent: October 29, 2002
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Toru Takayama, Takaaki Baba, James S. Harris, Jr.
  • Patent number: 6472679
    Abstract: Group III-nitride quaternary and pentenary material systems and methods are disclosed for use in semiconductor structures, including laser diodes, transistors, and photodetectors, which reduces or eliminates phase separation and provides increased emission efficiency. In an exemplary embodiment the semiconductor structure includes a first ternary, quaternary or pentenary material layer using an InGaAlNP layer of a first conduction type formed substantially without phase separation, a quaternary or pentenary material active layer using an InGaAlNP active layer substantially without phase separation, and a third ternary, quaternary or pentenary InGaAlNP material layer of an opposite conduction type formed substantially without phase separation.
    Type: Grant
    Filed: December 31, 1999
    Date of Patent: October 29, 2002
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Toru Takayama, Takaaki Baba, James S. Harris, Jr.
  • Patent number: 6903364
    Abstract: Group III-nitride quaternary and pentenary material systems and methods are disclosed for use in semiconductor structures, including laser diodes, transistors, and photodetectors, which reduce or eliminate phase separation and provide increased emission efficiency. In an exemplary embodiment the semiconductor structure includes a first ternary, quaternary or pentenary material layer using BlnGaAlN material system of a first conduction type formed substantially without phase separation, and a quaternary or pentenary material active layer using BlnGaAlN material system substantially without phase separation, and a third ternary, quaternary or pentenary material layer using BlnGaAlN material system of an opposite conduction type formed substantially without phase separation.
    Type: Grant
    Filed: November 16, 1999
    Date of Patent: June 7, 2005
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Toru Takayama, Takaaki Baba, James S. Harris, Jr.