Patents by Inventor Supratik Guha

Supratik Guha 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: 20120070936
    Abstract: In an annealing process, a Kesterite film is provided on a substrate. The Kesterite film and the substrate are generally planar, have an interface, and have a substrate exterior side and a Kesterite exterior side. An additional step includes locating the cap adjacent the Kesterite exterior side. A further step includes applying sufficient heat to the Kesterite film and the substrate for a sufficient time to anneal the Kesterite film. The annealing is carried out with the cap adjacent the Kesterite exterior side. In another aspect, the film is not limited to Kesterite, and the cap is employed without any precursor layer thereon. Solar cell manufacturing techniques employing the annealing techniques are also disclosed.
    Type: Application
    Filed: June 3, 2011
    Publication date: March 22, 2012
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Supratik Guha, David B. Mitzi, Teodor K. Todorov, Kejia Wang
  • Patent number: 8138102
    Abstract: A method of placing a functionalized semiconducting nanostructure, includes functionalizing a semiconducting nanostructure including one of a nanowire and a nanocrystal, with an organic functionality including a functional group for bonding to a bonding surface, dispersing the functionalized semiconducting nanostructure in a solvent to form a dispersion, and depositing the dispersion onto the bonding surface.
    Type: Grant
    Filed: August 21, 2008
    Date of Patent: March 20, 2012
    Assignee: International Business Machines Corporation
    Inventors: Ali Afzali-Ardakani, Supratik Guha, Cherie R. Kagan, George S. Tulevski, Emanuel Tutuc
  • Patent number: 8120132
    Abstract: A photovoltaic cell and a method of forming an electrode grid on a photovoltaic semiconductor substrate of a photovoltaic cell are disclosed. In one embodiment, the photovoltaic cell comprises a photovoltaic semiconductor substrate; a back electrode electrically connected to a back surface of the substrate; and a front electrode electrically connected to a front surface of the substrate. The substrate, back electrode, and front electrode form an electric circuit for generating an electric current when said substrate absorbs light. The front electrode is comprised of a metal grid defining a multitude of holes. These holes may be periodic, aperiodic, or partially periodic. The front electrode may be formed by depositing nanospheres on the substrate; forming a metallic layer on the substrate, around the nanospheres; and removing the nanospheres, leaving an electrode grid defining a multitude of holes on the substrate.
    Type: Grant
    Filed: August 2, 2011
    Date of Patent: February 21, 2012
    Assignee: International Business Machines Corporation
    Inventors: Supratik Guha, Oki Gunawan
  • Patent number: 8119904
    Abstract: A multi-junction photovoltaic device includes a silicon substrate and a dielectric layer formed on the silicon substrate. A germanium layer is formed on the dielectric layer. The germanium includes a crystalline structure that is substantially similar to the crystalline structure of the silicon substrate. A first photovoltaic sub-cell includes a first plurality of doped semiconductor layers formed on the germanium layer. At least a second photovoltaic sub-cell includes a second plurality of doped semiconductor layers formed on the first photovoltaic sub-cell that is on the germanium layer that is on the dielectric layer.
    Type: Grant
    Filed: July 31, 2009
    Date of Patent: February 21, 2012
    Assignee: International Business Machines Corporation
    Inventors: Supratik Guha, Harold J. Hovel
  • Patent number: 8115097
    Abstract: Electrical contact to the front side of a photovoltaic cell is provided by an array of conductive through-substrate vias, and optionally, an array of conductive blocks located on the front side of the photovoltaic cell. A dielectric liner provides electrical isolation of each conductive through-substrate via from the semiconductor material of the photovoltaic cell. A dielectric layer on the backside of the photovoltaic cell is patterned to cover a contiguous region including all of the conductive through-substrate vias, while exposing a portion of the backside of the photovoltaic cell. A conductive material layer is deposited on the back surface of the photovoltaic cell, and is patterned to form a first conductive wiring structure that electrically connects the conductive through-substrate vias and a second conductive wiring structure that provides electrical connection to the backside of the photovoltaic cell.
    Type: Grant
    Filed: November 19, 2009
    Date of Patent: February 14, 2012
    Assignee: International Business Machines Corporation
    Inventors: Supratik Guha, Yves Martin, Naim Moumen, Robert L. Sandstrom, Theodore G. van Kessel
  • Publication number: 20120006318
    Abstract: A method of concentrating solar energy includes receiving solar energy through a surface of an optically clear shell, guiding the solar energy through a liquid contained in the optically clear shell, folding the solar energy back through the liquid toward a solar receiver, and shifting the solar receiver within the optically clear shell to track the sun, wherein the solar energy collected by the solar receiver is converted into electrical energy.
    Type: Application
    Filed: September 20, 2011
    Publication date: January 12, 2012
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Supratik Guha, Philip C. Hobbs, Yves C. Martin, Robert L. Sandstrom, Theodore G. van Kessel
  • Publication number: 20110284073
    Abstract: A photovoltaic cell and a method of forming an electrode grid on a photovoltaic semiconductor substrate of a photovoltaic cell are disclosed. In one embodiment, the photovoltaic cell comprises a photovoltaic semiconductor substrate; a back electrode electrically connected to a back surface of the substrate; and a front electrode electrically connected to a front surface of the substrate. The substrate, back electrode, and front electrode form an electric circuit for generating an electric current when said substrate absorbs light. The front electrode is comprised of a metal grid defining a multitude of holes. These holes may be periodic, aperiodic, or partially periodic. The front electrode may be formed by depositing nanospheres on the substrate; forming a metallic layer on the substrate, around the nanospheres; and removing the nanospheres, leaving an electrode grid defining a multitude of holes on the substrate.
    Type: Application
    Filed: August 2, 2011
    Publication date: November 24, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Supratik Guha, Oki Gunawan
  • Patent number: 8039292
    Abstract: A photovoltaic cell and a method of forming an electrode grid on a photovoltaic semiconductor substrate of a photovoltaic cell are disclosed. In one embodiment, the photovoltaic cell comprises a photovoltaic semiconductor substrate; a back electrode electrically connected to a back surface of the substrate; and a front electrode electrically connected to a front surface of the substrate. The substrate, back electrode, and front electrode form an electric circuit for generating an electric current when said substrate absorbs light. The front electrode is comprised of a metal grid defining a multitude of holes. These holes may be periodic, aperiodic, or partially periodic. The front electrode may be formed by depositing nanospheres on the substrate; forming a metallic layer on the substrate, around the nanospheres; and removing the nanospheres, leaving an electrode grid defining a multitude of holes on the substrate.
    Type: Grant
    Filed: November 18, 2009
    Date of Patent: October 18, 2011
    Assignee: International Business Machines Corporation
    Inventors: Supratik Guha, Oki Gunawan
  • Publication number: 20110235390
    Abstract: A memory device and a method of forming the same are provided. The memory device includes a substrate; a set of electrodes disposed on the substrate; a dielectric layer formed between the set of electrodes; and a transition metal oxide layer formed between the set of electrodes, the transition metal oxide layer configured to undergo a metal-insulator transition (MIT) to perform a read or write operation.
    Type: Application
    Filed: March 23, 2010
    Publication date: September 29, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Tymon Barwicz, Keith A. Jenkins, Supratik Guha
  • Patent number: 8026560
    Abstract: Techniques for ultra-sensitive detection are provided. In one aspect, a detection device is provided. The detection device comprises a source; a drain; a nanowire comprising a semiconductor material having a first end clamped to the source and a second end clamped to the drain and suspended freely therebetween; and a gate in close proximity to the nanowire.
    Type: Grant
    Filed: July 15, 2010
    Date of Patent: September 27, 2011
    Assignee: International Business Machines Corporation
    Inventors: Ali Afzali-Ardakani, Sudhir Gowda, Supratik Guha, Hendrik F. Hamann, Emanuel Tutuc
  • Patent number: 8026439
    Abstract: A solar concentration system includes an optically clear shell member having an outer surface and an inner surface, with the inner surface defining a hollow interior portion, a liquid contained within the hollow interior portion of the optically clear shell, and a solar collection system contained within the hollow interior portion of the optically clear shell. The solar collection system includes a tracking system configured and disposed to selectively shift within the hollow interior portion, a reflector member mounted to the tracking system, and a solar receiver mounted to the tracking system. The tracking system being configured and disposed orient the reflector member and the solar receiver to follow a path of the sun enhancing the collection of solar energy.
    Type: Grant
    Filed: November 20, 2009
    Date of Patent: September 27, 2011
    Assignee: International Business Machines Corporation
    Inventors: Supratik Guha, Philip C. Hobbs, Yves C. Martin, Robert L. Sandstrom, Theodore G. van Kessel
  • Publication number: 20110201163
    Abstract: A semiconductor structure is provided, which includes multiple sections arranged along a longitudinal axis. Preferably, the semiconductor structure comprises a middle section and two terminal sections located at opposite ends of the middle section. A semiconductor core having a first dopant concentration preferably extends along the longitudinal axis through the middle section and the two terminal sections. A semiconductor shell having a second, higher dopant concentration preferably encircles a portion of the semiconductor core at the two terminal sections, but not at the middle section, of the semiconductor structure. It is particularly preferred that the semiconductor structure is a nanostructure having a cross-sectional dimension of not more than 100 nm.
    Type: Application
    Filed: March 7, 2011
    Publication date: August 18, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Joerg Appenzeller, Supratik Guha, Emanuel Tutuc
  • Patent number: 7998788
    Abstract: Techniques for combining nanotechnology with photovoltaics are provided. In one aspect, a method of forming a photovoltaic device is provided comprising the following steps. A plurality of nanowires are formed on a substrate, wherein the plurality of nanowires attached to the substrate comprises a nanowire forest. In the presence of a first doping agent and a first volatile precursor, a first doped semiconductor layer is conformally deposited over the nanowire forest. In the presence of a second doping agent and a second volatile precursor, a second doped semiconductor layer is conformally deposited over the first doped layer. The first doping agent comprises one of an n-type doping agent and a p-type doping agent and the second doping agent comprises a different one of the n-type doping agent and the p-type doping agent from the first doping agent. A transparent electrode layer is deposited over the second doped semiconductor layer.
    Type: Grant
    Filed: July 27, 2006
    Date of Patent: August 16, 2011
    Assignee: International Business Machines Corporation
    Inventors: Supratik Guha, Hendrik F. Hamann, Emanuel Tutuc
  • Publication number: 20110180777
    Abstract: A semiconductor device includes a bonding surface, a semiconducting nanostructure including one of a nanowire and a nanocrystal, which is formed on the bonding surface, and a source electrode and a drain electrode which are formed on the nanostructure such that the nanostructure is electrically connected to the source and drain electrodes.
    Type: Application
    Filed: March 31, 2011
    Publication date: July 28, 2011
    Applicant: International Business Machines Corporation
    Inventors: Ali Afzali-Ardakani, Supratik Guha, Cherie R. Kagan, George S. Tulevski, Emanuel Tutuc
  • Publication number: 20110168247
    Abstract: Solar concentrator devices and techniques for the fabrication thereof are provided. In one aspect, a solar concentrator device is provided. The solar concentrator device comprises at least one solar converter cell; a heat sink; and a liquid metal between the solar converter cell and the heat sink, configured to thermally couple the solar converter cell and the heat sink during operation of the device. The solar converter cell can comprise a triple junction semiconductor solar converter cell fabricated on a germanium (Ge) substrate. The heat sink can comprise a vapor chamber heat sink. The liquid metal can comprise a gallium (Ga) alloy and have a thermal resistance of less than or equal to about five square millimeter degree Celsius per Watt (mm2° C./W).
    Type: Application
    Filed: March 23, 2011
    Publication date: July 14, 2011
    Applicant: International Business Machines Corporation
    Inventors: Supratik Guha, Theodore Gerard van Kessel, Yves C. Martin
  • Publication number: 20110168167
    Abstract: A solar concentrator includes an optical member having a focal point. The optical member is configured and disposed to direct incident solar radiation to the focal point. A support member is positioned adjacent to the focal point of the optical member. A solar energy collector is supported upon the support member. The solar energy collector is positioned at the focal point of the optical member. A base member is positioned in a spaced relationship from the support member. The base member and the support member define a chamber section that is in a heat exchange relationship with the solar energy collector. The chamber section is configured to absorb and dissipate heat from the solar energy collectors.
    Type: Application
    Filed: January 13, 2010
    Publication date: July 14, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Supratik Guha, Yves C. Martin, Robert L. Sandstrom, Theodore G. van Kessel
  • Patent number: 7977690
    Abstract: Techniques for combining nanotechnology with photovoltaics are provided. In one aspect, a method of forming a photovoltaic device is provided comprising the following steps. A plurality of nanowires are formed on a substrate, wherein the plurality of nanowires attached to the substrate comprises a nanowire forest. In the presence of a first doping agent and a first volatile precursor, a first doped semiconductor layer is conformally deposited over the nanowire forest. In the presence of a second doping agent and a second volatile precursor, a second doped semiconductor layer is conformally deposited over the first doped layer. The first doping agent comprises one of an n-type doping agent and a p-type doping agent and the second doping agent comprises a different one of the n-type doping agent and the p-type doping agent from the first doping agent. A transparent electrode layer is deposited over the second doped semiconductor layer.
    Type: Grant
    Filed: August 19, 2009
    Date of Patent: July 12, 2011
    Assignee: International Business Machines Corporation
    Inventors: Supratik Guha, Hendrik F. Hamann, Emanuel Tutuc
  • Publication number: 20110165724
    Abstract: Techniques for combining nanotechnology with photovoltaics are provided. In one aspect, a method of forming a photovoltaic device is provided comprising the following steps. A plurality of nanowires are formed on a substrate, wherein the plurality of nanowires attached to the substrate comprises a nanowire forest. In the presence of a first doping agent and a first volatile precursor, a first doped semiconductor layer is conformally deposited over the nanowire forest. In the presence of a second doping agent and a second volatile precursor, a second doped semiconductor layer is conformally deposited over the first doped layer. The first doping agent comprises one of an n-type doping agent and a p-type doping agent and the second doping agent comprises a different one of the n-type doping agent and the p-type doping agent from the first doping agent. A transparent electrode layer is deposited over the second doped semiconductor layer.
    Type: Application
    Filed: July 27, 2006
    Publication date: July 7, 2011
    Inventors: Supratik Guha, Hendrik F. Hamann, Emanuel Tutuc
  • Publication number: 20110165767
    Abstract: The present invention provides a semiconductor structure including a semiconductor substrate having a plurality of source and drain diffusion regions located therein, each pair of source and drain diffusion regions are separated by a device channel. The structure further includes a first gate stack of pFET device located on top of some of the device channels, the first gate stack including a high-k gate dielectric, an insulating interlayer abutting the gate dielectric and a fully silicided metal gate electrode abutting the insulating interlayer, the insulating interlayer includes an insulating metal nitride that stabilizes threshold voltage and flatband voltage of the p-FET device to a targeted value and is one of aluminum oxynitride, boron nitride, boron oxynitride, gallium nitride, gallium oxynitride, indium nitride and indium oxynitride.
    Type: Application
    Filed: March 14, 2011
    Publication date: July 7, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Nestor A. Bojarczuk, JR., Cyril Cabral, JR., Eduard A. Cartier, Matthew W. Copel, Martin M. Frank, Evgeni P. Gousev, Supratik Guha, Rajarao Jammy, Vijay Narayanan, Vamsi K. Paruchuri
  • Publication number: 20110156133
    Abstract: A semiconductor structure is provided, which includes multiple sections arranged along a longitudinal axis. Preferably, the semiconductor structure comprises a middle section and two terminal sections located at opposite ends of the middle section. A semiconductor core having a first dopant concentration preferably extends along the longitudinal axis through the middle section and the two terminal sections. A semiconductor shell having a second, higher dopant concentration preferably encircles a portion of the semiconductor core at the two terminal sections, but not at the middle section, of the semiconductor structure. It is particularly preferred that the semiconductor structure is a nanostructure having a cross-sectional dimension of not more than 100 nm.
    Type: Application
    Filed: March 7, 2011
    Publication date: June 30, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Joerg Appenzeller, Supratik Guha, Emanuel Tutuc