Patents by Inventor Michael R. T. Tan

Michael R. T. Tan 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: 7276390
    Abstract: An InAsP active region for a long wavelength light emitting device and a method for growing the same are disclosed. In one embodiment, the method comprises placing a substrate in an organometallic vapor phase epitaxy (OMVPE) reactor, the substrate for supporting growth of an indium arsenide phosphide (InAsP) film, forming a quantum well layer of InAsP, and forming a barrier layer adjacent the quantum well layer, where the quantum well layer and the barrier layer are formed at a temperature of less than 520 degrees C. Forming the quantum well layer and the barrier layer at a temperature of less than 520 degrees C. results in fewer dislocations by suppressing relaxation of the layers. A long wavelength active region including InAsP quantum well layers and InGaP barrier layers is also disclosed.
    Type: Grant
    Filed: August 29, 2002
    Date of Patent: October 2, 2007
    Assignee: Avago Technologies General IP Pte Ltd
    Inventors: David P. Bour, Michael R. T. Tan, William H. Perez
  • Patent number: 7269196
    Abstract: The method comprises forming barrier layers of AlxGa1-xAs, forming a quantum well layer of InGaAs between the barrier layers, and forming an interfacial layer between the quantum well layer and each of the barrier layers.
    Type: Grant
    Filed: July 6, 2004
    Date of Patent: September 11, 2007
    Assignee: Avago Technologies Fiber IP (Singapore) Pte. Ltd.
    Inventors: Ashish Tandon, Michael R. T. Tan, Ying-Lan Chang
  • Patent number: 7215848
    Abstract: An optical isolator for coupling light from a first waveguide to a second waveguide is disclosed. The optical isolator utilizes a resonator coupled to the first and second optical waveguides. The resonator has a resonance at ? for light traveling from the first optical waveguide to the second optical waveguide; however, the resonator does not have a resonance at ? for light traveling from the second waveguide to the first waveguide. The resonator can use a layer of ferromagnetic material in an applied magnetic field. The magnetic field within the ferromagnetic material varies in strength and/or direction over the layer of ferromagnetic material. The magnetic field can be generated by an external magnetic field that varies over the layer of ferromagnetic material. Alternatively, the resonator can include a layer of ferromagnetic metal that overlies a portion of the layer of ferromagnetic material and a constant external magnetic field.
    Type: Grant
    Filed: January 29, 2004
    Date of Patent: May 8, 2007
    Assignee: Avago Technologies General IP (Singapore) Pte. Ltd.
    Inventors: Michael R. T. Tan, William Trutna, David P. Bour, Michael H. Leary
  • Patent number: 7072531
    Abstract: A light modulator having a waveguide and a resonator is disclosed. The waveguide routes light of wavelength ? past the resonator. The resonator is coupled to the waveguide such that a portion of the light is input to the resonator, the resonator having a resonance at ?. The resonator includes a gain region in which light of wavelength ? is amplified and an absorption region in which light of wavelength ? is absorbed, the absorption region having first and second states, the first state absorbing less light of wavelength ? than the second state, the state of the absorption region is determined by an electrical signal coupled to the absorption region. The gain region provides a gain that compensates for the light absorption in the first state. In one embodiment, the waveguide and resonator are critically coupled when the absorption region is in the second state.
    Type: Grant
    Filed: September 16, 2004
    Date of Patent: July 4, 2006
    Assignee: Agilent Technologies, Inc.
    Inventors: Kostadin D. Djordjev, Michael R. T. Tan, Chao-Kun Lin, Scott W. Corzine
  • Patent number: 7033938
    Abstract: The active region of a long-wavelength light emitting device is made by providing an organometallic vapor phase epitaxy (OMVPE) reactor, placing a substrate wafer capable of supporting growth of indium gallium arsenide nitride in the reactor, supplying a Group III–V precursor mixture comprising an arsenic precursor, a nitrogen precursor, a gallium precursor, an indium precursor and a carrier gas to the reactor and pressurizing the reactor to a sub-atmospheric elevated growth pressure no higher than that at which a layer of indium gallium arsenide layer having a nitrogen fraction commensurate with light emission at a wavelength longer than 1.2 ?m is deposited over the substrate wafer.
    Type: Grant
    Filed: February 23, 2004
    Date of Patent: April 25, 2006
    Inventors: David P. Bour, Tetsuya Takeuchi, Ashish Tandon, Ying-Lan Chang, Michael R. T. Tan, Scott W. Corzine
  • Patent number: 7034331
    Abstract: The tunnel junction structure comprises a p-type tunnel junction layer of a first semiconductor material, an n-type tunnel junction layer of a second semiconductor material and a tunnel junction between the tunnel junction layers. At least one of the semiconductor materials includes gallium (Ga), arsenic (As) and either nitrogen (N) or antimony (Sb). The probability of tunneling is significantly increased, and the voltage drop across the tunnel junction is consequently decreased, by forming the tunnel junction structure of materials having a reduced difference between the valence band energy of the material of the p-type tunnel junction layer and the conduction band energy of the n-type tunnel junction layer.
    Type: Grant
    Filed: June 4, 2004
    Date of Patent: April 25, 2006
    Assignee: Agilent Technologies, Inc.
    Inventors: Ying-Lan Chang, Ashish Tandon, Michael H. Leary, Michael R. T. Tan
  • Patent number: 6931044
    Abstract: A method and apparatus is provided for improving the temperature performance of GaAsSb materials utilizing an AlGaInP confinement structure. An active region containing a GaAsSb quantum well layer and (In)GaAs barrier layers is sandwiched between two AlGaInP confinement layers. AlGaInP confinement structures provide sufficient electron confinement, thereby improving the stability of the threshold current with respect to increasing temperature for GaAsSb/GaAs heterostructures.
    Type: Grant
    Filed: February 18, 2003
    Date of Patent: August 16, 2005
    Assignee: Agilent Technologies, Inc.
    Inventors: David P. Bour, Michael R. T. Tan, Ying-Lan Chang
  • Patent number: 6878970
    Abstract: Light-emitting devices are described. One example of a light-emitting device includes a first barrier layer and a second barrier layer, and a quantum well layer located between the first and second barrier layers. The first and second barrier layers are composed of gallium arsenide, and the quantum well layer is composed of indium gallium arsenide nitride. A first layer is located between the quantum well layer and the first barrier layer. The first layer has a bandgap energy between that of the first barrier layer and that of the quantum well layer. Another example of a light-emitting device includes a quantum well and a carrier capture element adjacent the quantum well. The carrier capture element increases the effective carrier capture cross-section of the quantum well.
    Type: Grant
    Filed: April 17, 2003
    Date of Patent: April 12, 2005
    Assignee: Agilent Technologies, Inc.
    Inventors: David P. Bour, Michael H. Leary, Ying-Lan Chang, Yoon-Kyu Song, Michael R. T. Tan, Tetsuya Takeuchi, Danielle Chamberlin
  • Publication number: 20040217343
    Abstract: The tunnel junction structure comprises a p-type tunnel junction layer of a first semiconductor material, an n-type tunnel junction layer of a second semiconductor material and a tunnel junction between the tunnel junction layers. At least one of the semiconductor materials includes gallium (Ga), arsenic (As) and either nitrogen (N) or antimony (Sb). The probability of tunneling is significantly increased, and the voltage drop across the tunnel junction is consequently decreased, by forming the tunnel junction structure of materials having a reduced difference between the valence band energy of the material of the p-type tunnel junction layer and the conduction band energy of the n-type tunnel junction layer.
    Type: Application
    Filed: June 4, 2004
    Publication date: November 4, 2004
    Inventors: Ying-Lan Chang, Ashish Tandon, Michael H. Leary, Michael R. T. Tan
  • Publication number: 20040219703
    Abstract: The active region of a long-wavelength light emitting device is made by providing an organometallic vapor phase epitaxy (OMVPE) reactor, placing a substrate wafer capable of supporting growth of indium gallium arsenide nitride in the reactor, supplying a Group III-V precursor mixture comprising an arsenic precursor, a nitrogen precursor, a gallium precursor, an indium precursor and a carrier gas to the reactor and pressurizing the reactor to a sub-atmospheric elevated growth pressure no higher than that at which a layer of indium gallium arsenide layer having a nitrogen fraction commensurate with light emission at a wavelength longer than 1.2 &mgr;m is deposited over the substrate wafer.
    Type: Application
    Filed: February 23, 2004
    Publication date: November 4, 2004
    Inventors: David P. Bour, Tetsuya Takeuchi, Ashish Tandon, Ying-Lan Chang, Michael R. T. Tan, Scott W. Corzine
  • Patent number: 6813295
    Abstract: Various asymmetric InGaAsN VCSEL structures that are made using an MOCVD process are presented. Use of the asymmetric structure effectively eliminates aluminum contamination of the quantum well active region.
    Type: Grant
    Filed: March 25, 2002
    Date of Patent: November 2, 2004
    Assignee: Agilent Technologies, Inc.
    Inventors: Tetsuya Takeuchi, Ying-Lan Chang, David P. Bour, Michael H. Leary, Michael R. T. Tan
  • Publication number: 20040206949
    Abstract: Light-emitting devices are described. One example of a light-emitting device includes a first barrier layer and a second barrier layer, and a quantum well layer located between the first and second barrier layers. The first and second barrier layers are composed of gallium arsenide, and the quantum well layer is composed of indium gallium arsenide nitride. A first layer is located between the quantum well layer and the first barrier layer. The first layer has a bandgap energy between that of the first barrier layer and that of the quantum well layer. Another example of a light-emitting device includes a quantum well and a carrier capture element adjacent the quantum well. The carrier capture element increases the effective carrier capture cross-section of the quantum well.
    Type: Application
    Filed: April 17, 2003
    Publication date: October 21, 2004
    Inventors: David P. Bour, Michael H. Leary, Ying-Lan Chang, Yoon-Kyu Song, Michael R. T. Tan, Tetsuya Takeuchi, Danielle Chamberlin
  • Publication number: 20040161005
    Abstract: A method and apparatus is provided for improving the temperature performance of GaAsSb materials utilizing an AlGaInP confinement structure. An active region containing a GaAsSb quantum well layer and (In)GaAs barrier layers is sandwiched between two AlGaInP confinement layers. AlGaInP confinement structures provide sufficient electron confinement, thereby improving the stability of the threshold current with respect to increasing temperature for GaAsSb/GaAs heterostructures.
    Type: Application
    Filed: February 18, 2003
    Publication date: August 19, 2004
    Inventors: David P. Bour, Michael R.T. Tan, Ying-Lan Chang
  • Publication number: 20040161006
    Abstract: An InGaAsN semiconductor light-emitting device containing one or more barrier layers is designed to prevent diffusion of one or more elements out of the quantum well. In one embodiment, the barrier layer can either contain nitrogen in substantially the same concentration as the InGaAsN layer or contain two or more group III elements in combination with nitrogen, where the fractional composition of the two or more group III elements and nitrogen is designed to minimize out-diffusion of nitrogen from the quantum well. In other embodiments, the barrier layer can contain indium and gallium to minimize In/Ga intermixing at the heterointerface to the quantum well. In further embodiments, a compressive-strained or lattice-matched intermediate layer can be added between the InGaAsN quantum well and a tensile-strained barrier layer to minimize strain-related out-diffusion of nitrogen.
    Type: Application
    Filed: February 18, 2003
    Publication date: August 19, 2004
    Inventors: Ying-Lan Chang, Tetsuya Takeuchi, Danny E. Mars, David P. Bour, Michael R.T. Tan
  • Patent number: 6764926
    Abstract: A method for making high quality InGaAsN semiconductor devices is presented. The method allows the making of high quality InGaAsN semiconductor devices using a single MOCVD reactor while avoiding aluminum contamination.
    Type: Grant
    Filed: March 25, 2002
    Date of Patent: July 20, 2004
    Assignee: Agilent Technologies, Inc.
    Inventors: Tetsuya Takeuchi, Ying-Lan Chang, David P. Bour, Michael H. Leary, Michael R. T. Tan, Andy Luan
  • Patent number: 6765238
    Abstract: The tunnel junction structure comprises a p-type tunnel junction layer of a first semiconductor material, an n-type tunnel junction layer of a second semiconductor material and a tunnel junction between the tunnel junction layers. At least one of the semiconductor materials includes gallium (Ga), arsenic (As) and either nitrogen (N) or antimony (Sb). The probability of tunneling is significantly increased, and the voltage drop across the tunnel junction is consequently decreased, by forming the tunnel junction structure of materials having a reduced difference between the valence band energy of the material of the p-type tunnel junction layer and the conduction band energy of the n-type tunnel junction layer.
    Type: Grant
    Filed: September 12, 2002
    Date of Patent: July 20, 2004
    Assignee: Agilent Technologies, Inc.
    Inventors: Yin-Lan Chang, Ashish Tandon, Michael H. Leary, Michael R. T. Tan
  • Patent number: 6756325
    Abstract: Several methods for producing an active region for a long wavelength light emitting device are disclosed. In one embodiment, the method comprises placing a substrate in an organometallic vapor phase epitaxy (OMVPE) reactor, the substrate for supporting growth of an indium gallium arsenide nitride (InGaAsN) film, supplying to the reactor a group-III-V precursor mixture comprising arsine, dimethylhydrazine, alkyl-gallium, alkyl-indium and a carrier gas, where the arsine and the dimethylhydrazine are the group-V precursor materials and where the percentage of dimethylhydrazine substantially exceeds the percentage of arsine, and pressurizing the reactor to a pressure at which a concentration of nitrogen commensurate with light emission at a wavelength longer than 1.2 um is extracted from the dimethylhydrazine and deposited on the substrate.
    Type: Grant
    Filed: May 7, 2002
    Date of Patent: June 29, 2004
    Assignee: Agilent Technologies, Inc.
    Inventors: David P. Bour, Tetsuya Takeuchi, Ashish Tandon, Ying-Lan Chang, Michael R. T. Tan, Scott Corzine
  • Patent number: 6730944
    Abstract: The invention provides a laser structure that operates at a wavelength of 1.3 &mgr;m and at elevated temperatures and a method of making same. The laser structure includes a quantum well layer of InAsP. The quantum well layer is sandwiched between a first barrier layer and a second barrier layer. Each barrier layer exhibits a higher bandgap energy than the quantum well layer. Also, each barrier layer comprises Gax(AlIn)1−xP in which x 0. This material has a higher bandgap energy than conventional barrier layer materials, such as InGaP. The resulting larger conduction band discontinuity leads to improved high temperature performance without increasing the threshold current of the laser structure.
    Type: Grant
    Filed: January 30, 2003
    Date of Patent: May 4, 2004
    Assignee: Agilent Technologies, Inc.
    Inventors: Ashish Tandon, Ying-Ian Chang, Scott W. Corzine, David P. Bour, Michael R. T. Tan
  • Patent number: 6711195
    Abstract: The long-wavelength photonic device comprises an active region that includes at least one quantum-well layer of a quantum-well layer material that comprises InyGa1-yAsSb in which y≧0, and that additionally includes a corresponding number of barrier layers each of a barrier layer material that includes gallium and phosphorus. The barrier layer material has a conduction-band energy level greater than the conduction-band energy level of the quantum-well layer material and has a valence-band energy level less than the valence-band energy level of the quantum-well layer material.
    Type: Grant
    Filed: February 28, 2002
    Date of Patent: March 23, 2004
    Assignee: Agilent Technologies, Inc.
    Inventors: Ying-Lan Chang, Scott W. Corzine, Russell D. Dupuis, Min Soo Noh, Jae Hyun Ryou, Michael R. T. Tan, Ashish Tandon
  • Publication number: 20040051113
    Abstract: The tunnel junction structure comprises a p-type tunnel junction layer of a first semiconductor material, an n-type tunnel junction layer of a second semiconductor material and a tunnel junction between the tunnel junction layers. At least one of the semiconductor materials includes gallium (Ga), arsenic (As) and either nitrogen (N) or antimony (Sb). The probability of tunneling is significantly increased, and the voltage drop across the tunnel junction is consequently decreased, by forming the tunnel junction structure of materials having a reduced difference between the valence band energy of the material of the p-type tunnel junction layer and the conduction band energy of the n-type tunnel junction layer.
    Type: Application
    Filed: September 12, 2002
    Publication date: March 18, 2004
    Inventors: Ying-Lan Chang, Ashish Tandon, Michael H. Leary, Michael R. T. Tan