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: 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: 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: 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
  • 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: 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: 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
  • Patent number: 6650684
    Abstract: A surface-emitting laser (“SEL”) having predictable filamentation initiation. The SEL includes a light generation layer and first and second mirror layers. The first and second mirror layers reflect light generated in the light generation region back toward the light generation region. Each of the mirrors reflects light such that it adds coherently to the light generated in the light generation region or to the light reflected from the other mirror. One of the mirrors includes a localized imperfection which causes light interacting therewith to be attenuated or shifted in phase relative to light that does not interact with the imperfection region. As a result, lasing filaments are preferentially initiated in the regions adjacent to the localized imperfection.
    Type: Grant
    Filed: December 1, 1995
    Date of Patent: November 18, 2003
    Assignee: Agilent Technologies, Inc.
    Inventors: Michael R. T. Tan, Kenneth H. Hahn, Long Yang, Shih-Yuan Wang
  • Patent number: 6647050
    Abstract: A short-wavelength vertical cavity surface emitting laser (VCSEL) is flip-chip bonded to a long-wavelength VCSEL. The short-wavelength VCSEL is used to optically-pump the long-wavelength VCSEL. Certain embodiments of the invention can serve as optical sources for optical fiber communication systems. Methods also are provided.
    Type: Grant
    Filed: September 18, 2001
    Date of Patent: November 11, 2003
    Assignee: Agilent Technologies, Inc.
    Inventors: Albert T. Yuen, Michael R. T. Tan, Dubravko Ivan Babic, Scott William Corzine
  • Publication number: 20030181024
    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: Application
    Filed: March 25, 2002
    Publication date: September 25, 2003
    Inventors: Tetsuya Takeuchi, Ying-Lan Chang, David P. Bour, Michael H. Leary, Michael R. T. Tan, Andy Luan
  • Patent number: 6553051
    Abstract: An optical assembly includes an optical subassembly containing a prefabricated long wavelength laser optically coupled to a prefabricated short wavelength laser located in a housing. The optical subassembly may be removably installed in the housing in which the short wavelength laser is contained. The short wavelength laser optically pumps the long wavelength laser resulting in a long wavelength laser output. The optical subassembly allows the independent fabrication, optimization and testing of the short wavelength laser and the long wavelength laser.
    Type: Grant
    Filed: October 31, 2000
    Date of Patent: April 22, 2003
    Assignee: Agilent Technologies, Inc.
    Inventors: Michael R. T. Tan, Scott W. Corzine, Dubravko I. Babic, Albert T. Yuen
  • Publication number: 20030053510
    Abstract: A short-wavelength vertical cavity surface emitting laser (VCSEL) is flip-chip bonded to a long-wavelength VCSEL. The short-wavelength VCSEL is used to optically-pump the long-wavelength VCSEL. Certain embodiments of the invention can serve as optical sources for optical fiber communication systems. Methods also are provided.
    Type: Application
    Filed: September 18, 2001
    Publication date: March 20, 2003
    Inventors: Albert T. Yuen, Michael R. T. Tan, Dubravko Ivan Babic, Scott William Corzine
  • Patent number: 6483862
    Abstract: A light emitting device and photodetector combination having a structure in which the layer of the photodetector that contacts the light emitting device is separated from the light emitting device by a native semiconductor oxide layer that is both insulating and has a refractive index lower than that of the light emitting device and the photodetector. This configuration results in a light emitting device and photodetector structure that minimizes the capture of the spontaneous emission light output from the light emitting device by the photodetector while electrically isolating the light emitting device from the photodetector. The electrical isolation of the light emitting device from the photodetector results in a four terminal device in which the light emitting device and photodetector may be independently biased, and can therefore be operated at a very low bias voltage.
    Type: Grant
    Filed: December 11, 1998
    Date of Patent: November 19, 2002
    Assignee: Agilent Technologies, Inc.
    Inventors: Lewis B. Aronson, Michael R. T. Tan, Scott W. Corzine, Dubravko I. Babic