Patents by Inventor Tze-Chiang Chen

Tze-Chiang Chen 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: 10115916
    Abstract: Device architectures based on trapping and de-trapping holes or electrons and/or recombination of both types of carriers are obtained by carrier trapping either in near-interface deep ambipolar states or in quantum wells/dots, either serving as ambipolar traps in semiconductor layers or in gate dielectric/barrier layers. In either case, the potential barrier for trapping is small and retention is provided by carrier confinement in the deep trap states and/or quantum wells/dots. The device architectures are usable as three terminal or two terminal devices.
    Type: Grant
    Filed: April 11, 2015
    Date of Patent: October 30, 2018
    Assignee: International Business Machines Corporation
    Inventors: Ali Afzali-Ardakani, Tze-Chiang Chen, Kailash Gopalakrishnan, Bahman Hekmatshoartabari
  • Publication number: 20180254361
    Abstract: A photovoltaic device and method include a crystalline substrate and an emitter contact portion formed in contact with the substrate. A back-surface-field junction includes a homogeneous junction layer formed in contact with the crystalline substrate and having a same conductivity type and a higher active doping density than that of the substrate. The homogeneous junction layer includes a thickness less than a diffusion length of minority carriers in the homogeneous junction layer. A passivation layer is formed in contact with the homogeneous junction layer opposite the substrate, which is either undoped or has the same conductivity type as that of the substrate.
    Type: Application
    Filed: April 30, 2018
    Publication date: September 6, 2018
    Inventors: TZE-CHIANG CHEN, BAHMAN HEKMATSHOARTABARI, DEVENDRA K. SADANA, DAVOOD SHAHRJERDI
  • Patent number: 10043935
    Abstract: A photovoltaic device includes a crystalline substrate having a first dopant conductivity, an interdigitated back contact and a front surface field structure. The front surface field structure includes a crystalline layer formed on the substrate and a noncrystalline layer formed on the crystalline layer. The crystalline layer and the noncrystalline layer are doped with dopants having a same dopant conductivity as the substrate. Methods are also disclosed.
    Type: Grant
    Filed: November 19, 2015
    Date of Patent: August 7, 2018
    Assignee: International Business Machines Corporation
    Inventors: Tze-Chiang Chen, Bahman Hekmatshoartabari, Devendra K. Sadana, Davood Shahrjerdi
  • Publication number: 20180212094
    Abstract: A photovoltaic device includes a crystalline substrate having a first dopant conductivity, an interdigitated back contact and a front surface field structure. The front surface field structure includes a crystalline layer formed on the substrate and a noncrystalline layer formed on the crystalline layer. The crystalline layer and the noncrystalline layer are doped with dopants having an opposite dopant conductivity from that of the substrate. Methods are also disclosed.
    Type: Application
    Filed: March 21, 2018
    Publication date: July 26, 2018
    Inventors: TZE-CHIANG CHEN, BAHMAN HEKMATSHOARTABARI, DEVENDRA K. SADANA, DAVOOD SHAHRJERDI
  • Patent number: 10008624
    Abstract: A photovoltaic device and method include a crystalline substrate and an emitter contact portion formed in contact with the substrate. A back-surface-field junction includes a homogeneous junction layer formed in contact with the crystalline substrate and having a same conductivity type and a higher active doping density than that of the substrate. The homogeneous junction layer includes a thickness less than a diffusion length of minority carriers in the homogeneous junction layer. A passivation layer is formed in contact with the homogeneous junction layer opposite the substrate, which is either undoped or has the same conductivity type as that of the substrate.
    Type: Grant
    Filed: September 28, 2015
    Date of Patent: June 26, 2018
    Assignee: International Business Machines Corporation
    Inventors: Tze-Chiang Chen, Bahman Hekmatshoartabari, Devendra K. Sadana, Davood Shahrjerdi
  • Patent number: 10003036
    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: February 13, 2017
    Date of Patent: June 19, 2018
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Ali Afzali-Ardakani, Tze-Chiang Chen, Oki Gunawan, Bahman Hekmatshoartabari
  • Patent number: 9985167
    Abstract: A photovoltaic device includes a crystalline substrate having a first dopant conductivity, an interdigitated back contact and a front surface field structure. The front surface field structure includes a crystalline layer formed on the substrate and a noncrystalline layer formed on the crystalline layer. The crystalline layer and the noncrystalline layer are doped with dopants having an opposite dopant conductivity from that of the substrate. Methods are also disclosed.
    Type: Grant
    Filed: August 14, 2013
    Date of Patent: May 29, 2018
    Assignee: International Business Machines Corporation
    Inventors: Tze-Chiang Chen, Bahman Hekmatshoartabari, Devendra K. Sadana, Davood Shahrjerdi
  • Patent number: 9972797
    Abstract: Device architectures based on trapping and de-trapping holes or electrons and/or recombination of both types of carriers are obtained by carrier trapping either in near-interface deep ambipolar states or in quantum wells/dots, either serving as ambipolar traps in semiconductor layers or in gate dielectric/barrier layers. In either case, the potential barrier for trapping is small and retention is provided by carrier confinement in the deep trap states and/or quantum wells/dots. The device architectures are usable as three terminal or two terminal devices.
    Type: Grant
    Filed: July 15, 2017
    Date of Patent: May 15, 2018
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Ali Afzali-Ardakani, Tze-Chiang Chen, Kailash Gopalakrishnan, Bahman Hekmatshoartabari
  • Patent number: 9911888
    Abstract: A method for forming a photovoltaic device includes providing a substrate. A layer is deposited to form one or more layers of a photovoltaic stack on the substrate. The depositing of the amorphous layer includes performing a high power flash deposition for depositing a first portion of the layer. A low power deposition is performed for depositing a second portion of the layer.
    Type: Grant
    Filed: December 21, 2015
    Date of Patent: March 6, 2018
    Assignee: International Business Machines Corporation
    Inventors: Tze-Chiang Chen, Augustin J. Hong, Jeehwan Kim, Devendra K. Sadana
  • Patent number: 9859455
    Abstract: A photovoltaic device includes a crystalline substrate having a first dopant conductivity, an interdigitated back contact and a front surface field structure. The front surface field structure includes a crystalline layer formed on the substrate and a noncrystalline layer formed on the crystalline layer. The crystalline layer and the noncrystalline layer are doped with dopants having an opposite dopant conductivity from that of the substrate. Methods are also disclosed.
    Type: Grant
    Filed: February 8, 2013
    Date of Patent: January 2, 2018
    Assignee: International Business Machines Corporation
    Inventors: Tze-Chiang Chen, Bahman Hekmatshoartabari, Devendra K. Sadana, Davood Shahrjerdi
  • Publication number: 20170317304
    Abstract: Device architectures based on trapping and de-trapping holes or electrons and/or recombination of both types of carriers are obtained by carrier trapping either in near-interface deep ambipolar states or in quantum wells/dots, either serving as ambipolar traps in semiconductor layers or in gate dielectric/barrier layers. In either case, the potential barrier for trapping is small and retention is provided by carrier confinement in the deep trap states and/or quantum wells/dots. The device architectures are usable as three terminal or two terminal devices.
    Type: Application
    Filed: July 15, 2017
    Publication date: November 2, 2017
    Inventors: Ali Afzali-Ardakani, Tze-Chiang Chen, Kailash Gopalakrishnan, Bahman Hekmatshoartabari
  • Patent number: 9735383
    Abstract: Device architectures based on trapping and de-trapping holes or electrons and/or recombination of both types of carriers are obtained by carrier trapping either in near-interface deep ambipolar states or in quantum wells/dots, either serving as ambipolar traps in semiconductor layers or in gate dielectric/barrier layers. In either case, the potential barrier for trapping is small and retention is provided by carrier confinement in the deep trap states and/or quantum wells/dots. The device architectures are usable as three terminal or two terminal devices.
    Type: Grant
    Filed: September 12, 2016
    Date of Patent: August 15, 2017
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Ali Afzali-Ardakani, Tze-Chiang Chen, Kailash Gopalakrishnan, Bahman Hekmatshoartabari
  • Publication number: 20170179412
    Abstract: Junction field-effect transistors including inorganic channels and organic gate junctions are used in some applications for forming high resolution active matrix displays. Arrays of such junction field-effect transistors are electrically connected to thin film switching transistors and provide high drive currents for passive devices such as organic light emitting diodes.
    Type: Application
    Filed: March 1, 2017
    Publication date: June 22, 2017
    Inventors: Ali Afzali-Ardakani, Tze-Chiang Chen, Bahman Hekmatshoartabari, Ghavam G. Shahidi
  • 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: 9640699
    Abstract: A photovoltaic device includes a crystalline substrate having a first dopant conductivity, an interdigitated back contact and a front surface field structure. The front surface field structure includes a crystalline layer formed on the substrate and a noncrystalline layer formed on the crystalline layer. The crystalline layer and the noncrystalline layer are doped with dopants having a same dopant conductivity as the substrate. Methods are also disclosed.
    Type: Grant
    Filed: February 8, 2013
    Date of Patent: May 2, 2017
    Assignee: International Business Machines Corporation
    Inventors: Tze-Chiang Chen, Bahman Hekmatshoartabari, Devendra K. Sadana, Davood Shahrjerdi
  • Patent number: 9620726
    Abstract: Junction field-effect transistors including inorganic channels and organic gate junctions are used in some applications for forming high resolution active matrix displays. Arrays of such junction field-effect transistors are electrically connected to thin film switching transistors and provide high drive currents for passive devices such as organic light emitting diodes.
    Type: Grant
    Filed: October 15, 2015
    Date of Patent: April 11, 2017
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Ali Afzali-Ardakani, Tze-Chiang Chen, Bahman Hekmatshoartabari, Ghavam G. Shahidi
  • 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: 20170005281
    Abstract: Device architectures based on trapping and de-trapping holes or electrons and/or recombination of both types of carriers are obtained by carrier trapping either in near-interface deep ambipolar states or in quantum wells/dots, either serving as ambipolar traps in semiconductor layers or in gate dielectric/barrier layers. In either case, the potential barrier for trapping is small and retention is provided by carrier confinement in the deep trap states and/or quantum wells/dots. The device architectures are usable as three terminal or two terminal devices.
    Type: Application
    Filed: September 12, 2016
    Publication date: January 5, 2017
    Inventors: Ali Afzali-Ardakani, Tze-Chiang Chen, Kailash Gopalakrishnan, Bahman Hekmatshoartabari