Patents by Inventor Oki Gunawan

Oki Gunawan 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: 20170299410
    Abstract: Techniques for manipulating objects and for determining the position of the objects in parallel dipole line (PDL) trap systems are provided. In one aspect, a PDL trap is provided. The PDL trap includes: a pair of dipole line magnets connected to a potential, wherein the pair of dipole line magnets includes magnets having magnetizations perpendicular to long axes of the magnets; a diamagnetic rod levitating above the pair of dipole line magnets; and at least one electrode above the pair of dipole line magnets, adjacent to the diamagnetic rod. The system produces a hybrid one-dimensional electromagnetic potential which is tunable by voltage. Techniques for operating the PDL trap to manipulate the diamagnetic rod and to detect a position of the diamagnetic rod in the PDL trap are also provided.
    Type: Application
    Filed: April 18, 2016
    Publication date: October 19, 2017
    Inventor: Oki Gunawan
  • Patent number: 9772385
    Abstract: A rotating magnetic field Hall apparatus is provided and includes first and second magnets disposed in a master-slave configuration, a device-under-test (DUT) stage interposable between the first and second magnets on which a DUT is disposable in first or second orientations for Hall measurement or photoelectromagnetic (PEM) testing, respectively, controllers disposed to center the DUT stage between the first and second magnets and orthogonal magnetic field sensors disposed aside lateral sides of the first magnet to facilitate positional initialization of the first and second magnets and to generate in-phase and out-of-phase reference signals for phase-sensitive or lock-in Hall signal detection. The system also includes software system to perform signal processing to yield the final Hall signal.
    Type: Grant
    Filed: June 24, 2015
    Date of Patent: September 26, 2017
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Oki Gunawan, Michael A. Pereira
  • Publication number: 20170227615
    Abstract: A rotating magnetic field Hall apparatus is provided and includes first and second magnets disposed in a master-slave configuration, a device-under-test (DUT) stage interposable between the first and second magnets on which a DUT is disposable in first or second orientations for Hall measurement or photoelectromagnetic (PEM) testing, respectively, controllers disposed to center the DUT stage between the first and second magnets and orthogonal magnetic field sensors disposed aside lateral sides of the first magnet to facilitate positional initialization of the first and second magnets and to generate in-phase and out-of-phase reference signals for phase-sensitive or lock-in Hall signal detection. The system also includes software system to perform signal processing to yield the final Hall signal.
    Type: Application
    Filed: April 28, 2017
    Publication date: August 10, 2017
    Inventors: Oki Gunawan, Michael A. Pereira
  • Publication number: 20170194518
    Abstract: Techniques for forming an ohmic back contact for Ag2ZnSn(S,Se)4 photovoltaic devices. In one aspect, a method for forming a photovoltaic device includes the steps of: depositing a refractory electrode material onto a substrate; depositing a contact material onto the refractory electrode material, wherein the contact material includes a transition metal oxide; forming an absorber layer on the contact material, wherein the absorber layer includes Ag, Zn, Sn, and at least one of S and Se; annealing the absorber layer; forming a buffer layer on the absorber layer; and forming a top electrode on the buffer layer. The refractory electrode material may be Mo, W, Pt, Ti, TiN, FTO, and combinations thereof. The transition metal oxide may be TiO2, ZnO, SnO, ZnSnO, Ga2O3, and combinations thereof. A photovoltaic device is also provided.
    Type: Application
    Filed: December 30, 2015
    Publication date: July 6, 2017
    Inventors: Talia S. Gershon, Oki Gunawan, Richard A. Haight, Ravin Mankad
  • Publication number: 20170181941
    Abstract: Tunable sunscreen compositions include quantum confined nanoparticles selected from the group of zinc oxide nanoparticles, titanium oxide nanoparticles, and gallium nitride-based nanoparticles. The zinc oxide nanoparticles have particle sizes that provide either quantum confined absorption at wavelengths of 290 nm to about 400 nm or emission at about 275 nm to about 290 nm. Still further, the zinc oxide with the quantum confined absorption provides transmission of radiation at wavelengths of about 275 nm to about 290 nm.
    Type: Application
    Filed: December 28, 2015
    Publication date: June 29, 2017
    Inventors: Oki Gunawan, Huan Hu, Ning Li, Devendra K. Sadana
  • Publication number: 20170167981
    Abstract: Methods, apparatuses, and computer program products are provided where fluid, such as a blood sample, is entered into a microfluidic channel in a microchip where the microfluidic channel possesses a micro/nanopillar array for sorting molecules by size. When the fluid passes through the micro/nanopillar array it is separated into particles of interest or particles not of interest or both. When particles of interest are lit by a light source via a first waveguide in the microchip connecting the light source to the microfluidic channel, then lighted particles of interest can be detected by an optical detector via a second waveguide in the microchip connecting the optical detector to the microfluidic channel. The information from the optical detector can be analyzed further by connecting the microchip to a mobile computing device with its own processing abilities or abilities via the internet or cloud.
    Type: Application
    Filed: December 11, 2015
    Publication date: June 15, 2017
    Inventors: Huan Hu, Oki Gunawan, Ning Li, Devendra K. Sadana, Joshua T. Smith, William T. Spratt, Yann Astier
  • Patent number: 9678040
    Abstract: A rotating magnetic field Hall apparatus is provided and includes first and second magnets disposed in a master-slave configuration, a device-under-test (DUT) stage interposable between the first and second magnets on which a DUT is disposable in first or second orientations for Hall measurement or photoelectromagnetic (PEM) testing, respectively, controllers disposed to center the DUT stage between the first and second magnets and orthogonal magnetic field sensors disposed aside lateral sides of the first magnet to facilitate positional initialization of the first and second magnets and to generate in-phase and out-of-phase reference signals for phase-sensitive or lock-in Hall signal detection. The system also includes software system to perform signal processing to yield the final Hall signal.
    Type: Grant
    Filed: April 9, 2015
    Date of Patent: June 13, 2017
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Oki Gunawan, Michael A. Pereira
  • Publication number: 20170155068
    Abstract: A photovoltaic device includes an inorganic substrate having a surface; an organic monolayer disposed onto the surface of the inorganic substrate, the inorganic monolayer having the following formula: ˜X—Y, wherein X is an oxygen or a sulfur; Y is an alkyl chain, an alkenyl chain, or an alkynyl chain; and X covalently bonds to the surface of the inorganic substrate by a covalent bond; a doped organic material layer disposed onto the organic monolayer; and a conductive electrode disposed onto a portion of the doped organic material.
    Type: Application
    Filed: February 13, 2017
    Publication date: June 1, 2017
    Inventors: Ali Afzali-Ardakani, Tze-Chiang Chen, Oki Gunawan, Bahman Hekmatshoartabari
  • Patent number: 9660577
    Abstract: Techniques for solar cell electrical characterization are provided. In one aspect, a solar testing device is provided. The device includes a solar simulator; and a continuous neutral density filter in front of the solar simulator having regions of varying light attenuation levels ranging from transparent to opaque, the continuous neutral density filter having an area sufficiently large to filter all light generated by the solar simulator, and wherein a position of the continuous neutral density filter relative to the solar simulator is variable so as to control a light intensity produced by the device. A solar cell electrical characterization system and a method for performing a solar cell electrical characterization are also provided.
    Type: Grant
    Filed: November 18, 2016
    Date of Patent: May 23, 2017
    Assignee: International Business Machines Corporation
    Inventors: Oki Gunawan, Bao Lei
  • Patent number: 9651354
    Abstract: One or more embodiments are directed to a magnet configured to be coupled to an object under test, an array of sensors configured to measure a magnetic field associated with the magnet, and a circuit configured to obtain voltage readings based on the measured magnetic field from the array of sensors and compute a distance between the array of sensors and the magnet based on the obtained voltage readings.
    Type: Grant
    Filed: August 7, 2012
    Date of Patent: May 16, 2017
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventor: Oki Gunawan
  • Patent number: 9651353
    Abstract: One or more embodiments are directed to a magnet configured to be coupled to an object under test, an array of sensors configured to measure a magnetic field associated with the magnet, and a circuit configured to obtain voltage readings based on the measured magnetic field from the array of sensors and compute a distance between the array of sensors and the magnet based on the obtained voltage readings.
    Type: Grant
    Filed: July 24, 2012
    Date of Patent: May 16, 2017
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventor: Oki Gunawan
  • Publication number: 20170133539
    Abstract: Photovoltaic devices based on an Ag2ZnSn(S,Se)4 (AZTSSe) absorber and techniques for formation thereof are provided. In one aspect, a method for forming a photovoltaic device includes the steps of: coating a substrate with a conductive layer; contacting the substrate with an Ag source, a Zn source, a Sn source, and at least one of a S source and a Se source under conditions sufficient to form an absorber layer on the conductive layer having Ag, Zn, Sn, and at least one of S and Se; and annealing the absorber layer. Methods of doping the AZTSSe are provided. A photovoltaic device is also provided.
    Type: Application
    Filed: November 9, 2015
    Publication date: May 11, 2017
    Inventors: Talia S. Gershon, Supratik Guha, Oki Gunawan, Richard A. Haight, Yun Seog Lee
  • Patent number: 9608141
    Abstract: A photovoltaic device includes a substrate, a back contact comprising a stable low-work function material, a photovoltaic absorber material layer comprising Ag2ZnSn(S,Se)4 (AZTSSe) on a side of the back contact opposite the substrate, wherein the back contact forms an Ohmic contact with the photovoltaic absorber material layer, a buffer layer or Schottky contact layer on a side of the absorber layer opposite the back contact, and a top electrode on a side of the buffer layer opposite the absorber layer.
    Type: Grant
    Filed: December 14, 2015
    Date of Patent: March 28, 2017
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Talia S. Gershon, Oki Gunawan, Richard A. Haight, Yun Seog Lee
  • Patent number: 9608220
    Abstract: A photovoltaic device includes an inorganic substrate having a surface; an organic monolayer disposed onto the surface of the inorganic substrate, the inorganic monolayer having the following formula: ˜X—Y, wherein X is an oxygen or a sulfur; Y is an alkyl chain, an alkenyl chain, or an alkynyl chain; and X covalently bonds to the surface of the inorganic substrate by a covalent bond; a doped organic material layer disposed onto the organic monolayer; and a conductive electrode disposed onto a portion of the doped organic material.
    Type: Grant
    Filed: December 14, 2015
    Date of Patent: March 28, 2017
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Ali Afzali-Ardakani, Tze-Chiang Chen, Oki Gunawan, Bahman Hekmatshoartabari
  • Publication number: 20170084853
    Abstract: A photovoltaic device includes an inorganic substrate having a surface; an organic monolayer disposed onto the surface of the inorganic substrate, the inorganic monolayer having the following formula: ˜X—Y, wherein X is an oxygen or a sulfur; Y is an alkyl chain, an alkenyl chain, or an alkynyl chain; and X covalently bonds to the surface of the inorganic substrate by a covalent bond; a doped organic material layer disposed onto the organic monolayer; and a conductive electrode disposed onto a portion of the doped organic material.
    Type: Application
    Filed: December 14, 2015
    Publication date: March 23, 2017
    Inventors: Ali Afzali-Ardakani, Tze-Chiang Chen, Oki Gunawan, Bahman Hekmatshoartabari
  • Publication number: 20170084852
    Abstract: A photovoltaic device includes an inorganic substrate having a surface; an organic monolayer disposed onto the surface of the inorganic substrate, the inorganic monolayer having the following formula: ˜X—Y, wherein X is an oxygen or a sulfur; Y is an alkyl chain, an alkenyl chain, or an alkynyl chain; and X covalently bonds to the surface of the inorganic substrate by a covalent bond; a doped organic material layer disposed onto the organic monolayer; and a conductive electrode disposed onto a portion of the doped organic material.
    Type: Application
    Filed: September 17, 2015
    Publication date: March 23, 2017
    Inventors: Ali Afzali-Ardakani, Tze-Chiang Chen, Oki Gunawan, Bahman Hekmatshoartabari
  • Publication number: 20170070190
    Abstract: Techniques for solar cell electrical characterization are provided. In one aspect, a solar testing device is provided. The device includes a solar simulator; and a continuous neutral density filter in front of the solar simulator having regions of varying light attenuation levels ranging from transparent to opaque, the continuous neutral density filter having an area sufficiently large to filter all light generated by the solar simulator, and wherein a position of the continuous neutral density filter relative to the solar simulator is variable so as to control a light intensity produced by the device. A solar cell electrical characterization system and a method for performing a solar cell electrical characterization are also provided.
    Type: Application
    Filed: November 18, 2016
    Publication date: March 9, 2017
    Inventors: Oki Gunawan, Bao Lei
  • Publication number: 20170069861
    Abstract: Techniques for forming a transparent conducting oxide (TCO) top contact using a low temperature process are provided. In one aspect of the invention, a method of forming a TCO on a substrate is provided. The method includes the steps of: generating a source gas of the TCO using e-beam evaporation; generating atomic oxygen using RF plasma; and contacting the substrate with the TCO source gas and the atomic oxygen under conditions sufficient to form the TCO on the substrate. A photovoltaic device is also provided which includes a bottom cell; and a perovskite-based top cell on the kesterite-based bottom cell. The perovskite-based top cell includes a top electrode formed from a TCO.
    Type: Application
    Filed: September 4, 2015
    Publication date: March 9, 2017
    Inventors: Bruce A. Ek, Talia S. Gershon, Supratik Guha, Oki Gunawan, Teodor K. Todorov
  • Publication number: 20170070191
    Abstract: Techniques for solar cell electrical characterization are provided. In one aspect, a solar testing device is provided. The device includes a solar simulator; and a continuous neutral density filter in front of the solar simulator having regions of varying light attenuation levels ranging from transparent to opaque, the continuous neutral density filter having an area sufficiently large to filter all light generated by the solar simulator, and wherein a position of the continuous neutral density filter relative to the solar simulator is variable so as to control a light intensity produced by the device. A solar cell electrical characterization system and a method for performing a solar cell electrical characterization are also provided.
    Type: Application
    Filed: November 18, 2016
    Publication date: March 9, 2017
    Inventors: Oki Gunawan, Bao Lei
  • Patent number: 9576853
    Abstract: A magnetic trap is configured to arrange at least one diamagnetic rod. The magnetic trap includes first and second magnets on a substrate that forms the magnetic trap defining a template configured to self-assemble diamagnetic material. Each of the first and second magnets extends along a longitudinal direction to define a magnet length, and contact each other to define a contact line. The first magnet and the second magnet have a diametric magnetization in a direction perpendicular to the contact line and the longitudinal direction so as to generate a longitudinal energy potential that traps the diamagnetic rod along the longitudinal direction.
    Type: Grant
    Filed: May 31, 2016
    Date of Patent: February 21, 2017
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Qing Cao, Oki Gunawan