Patents by Inventor Venkatasubramani Balu

Venkatasubramani Balu 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: 20200119220
    Abstract: Tri-layer semiconductor stacks for patterning features on solar cells, and the resulting solar cells, are described herein. In an example, a solar cell includes a substrate. A semiconductor structure is disposed above the substrate. The semiconductor structure includes a P-type semiconductor layer disposed directly on a first semiconductor layer. A third semiconductor layer is disposed directly on the P-type semiconductor layer. An outermost edge of the third semiconductor layer is laterally recessed from an outermost edge of the first semiconductor layer by a width. An outermost edge of the P-type semiconductor layer is sloped from the outermost edge of the third semiconductor layer to the outermost edge of the third semiconductor layer. A conductive contact structure is electrically connected to the semiconductor structure.
    Type: Application
    Filed: December 9, 2019
    Publication date: April 16, 2020
    Inventors: Kieran Mark Tracy, David D. Smith, Venkatasubramani Balu, Asnat Masad, Ann Waldhauer
  • Publication number: 20200075784
    Abstract: Methods of fabricating solar cell emitter regions with differentiated P-type and N-type regions architectures, and resulting solar cells, are described. In an example, a back contact solar cell includes a substrate having a light-receiving surface and a back surface. A first polycrystalline silicon emitter region of a first conductivity type is disposed on a first thin dielectric layer disposed on the back surface of the substrate. A second polycrystalline silicon emitter region of a second, different, conductivity type is disposed on a second thin dielectric layer disposed on the back surface of the substrate. A third thin dielectric layer is disposed laterally directly between the first and second polycrystalline silicon emitter regions. A first conductive contact structure is disposed on the first polycrystalline silicon emitter region. A second conductive contact structure is disposed on the second polycrystalline silicon emitter region.
    Type: Application
    Filed: November 8, 2019
    Publication date: March 5, 2020
    Inventors: Seung Bum Rim, David D. Smith, Taiqing Qiu, Staffan Westerberg, Kieran Mark Tracy, Venkatasubramani Balu
  • Patent number: 10505068
    Abstract: Tri-layer semiconductor stacks for patterning features on solar cells, and the resulting solar cells, are described herein. In an example, a solar cell includes a substrate. A semiconductor structure is disposed above the substrate. The semiconductor structure includes a P-type semiconductor layer disposed directly on a first semiconductor layer. A third semiconductor layer is disposed directly on the P-type semiconductor layer. An outermost edge of the third semiconductor layer is laterally recessed from an outermost edge of the first semiconductor layer by a width. An outermost edge of the P-type semiconductor layer is sloped from the outermost edge of the third semiconductor layer to the outermost edge of the third semiconductor layer. A conductive contact structure is electrically connected to the semiconductor structure.
    Type: Grant
    Filed: February 25, 2019
    Date of Patent: December 10, 2019
    Assignee: SunPower Corporation
    Inventors: Kieran Mark Tracy, David D. Smith, Venkatasubramani Balu, Asnat Masad, Ann Waldhauer
  • Publication number: 20190267499
    Abstract: Methods of fabricating solar cell emitter regions with differentiated P-type and N-type regions architectures, and resulting solar cells, are described. In an example, a back contact solar cell can include a substrate having a light-receiving surface and a back surface. A first polycrystalline silicon emitter region of a first conductivity type is disposed on a first thin dielectric layer disposed on the back surface of the substrate. A second polycrystalline silicon emitter region of a second, different, conductivity type is disposed on a second thin dielectric layer disposed on the back surface of the substrate. A third thin dielectric layer is disposed over an exposed outer portion of the first polycrystalline silicon emitter region and is disposed laterally directly between the first and second polycrystalline silicon emitter regions. A first conductive contact structure is disposed on the first polycrystalline silicon emitter region.
    Type: Application
    Filed: March 4, 2019
    Publication date: August 29, 2019
    Inventors: David D. Smith, Timothy Weidman, Scott Harrington, Venkatasubramani Balu
  • Publication number: 20190207040
    Abstract: Chemical polishing of solar cell surfaces and the resulting structures are described herein. In an example, a method of fabricating a solar cell includes texturizing both first side and second side surfaces of a silicon substrate with a first hydroxide-based etch process. The method also includes reducing a surface roughness factor of the texturized second side surface of the silicon substrate with a second hydroxide-based etch process. The method also includes, subsequent to reducing the surface roughness factor of the texturized second side surface of the silicon substrate, forming emitter regions on the second side surface of the silicon substrate.
    Type: Application
    Filed: December 29, 2017
    Publication date: July 4, 2019
    Inventors: Scott HARRINGTON, Amada MONTESDEOCA SANTANA, Venkatasubramani BALU
  • Publication number: 20190189813
    Abstract: Tri-layer semiconductor stacks for patterning features on solar cells, and the resulting solar cells, are described herein. In an example, a solar cell includes a substrate. A semiconductor structure is disposed above the substrate. The semiconductor structure includes a P-type semiconductor layer disposed directly on a first semiconductor layer. A third semiconductor layer is disposed directly on the P-type semiconductor layer. An outermost edge of the third semiconductor layer is laterally recessed from an outermost edge of the first semiconductor layer by a width. An outermost edge of the P-type semiconductor layer is sloped from the outermost edge of the third semiconductor layer to the outermost edge of the third semiconductor layer. A conductive contact structure is electrically connected to the semiconductor structure.
    Type: Application
    Filed: February 25, 2019
    Publication date: June 20, 2019
    Inventors: Kieran Mark Tracy, David D. Smith, Venkatasubramani Balu, Asnat Masad, Ann Waldhauer
  • Publication number: 20190097068
    Abstract: Methods of fabricating solar cell emitter regions with differentiated P-type and N-type region architectures, and the resulting solar cells, are described herein. In an example, a solar cell includes an N-type semiconductor substrate having a light-receiving surface and a back surface. A plurality of N-type polycrystalline silicon regions is disposed on a first thin dielectric layer disposed on the back surface of the N-type semiconductor substrate. A plurality of P-type polycrystalline silicon regions is disposed on a second thin dielectric layer disposed in a corresponding one of a plurality of trenches interleaving the plurality of N-type polycrystalline silicon regions in the back surface of the N-type semiconductor substrate.
    Type: Application
    Filed: November 26, 2018
    Publication date: March 28, 2019
    Inventors: David D. Smith, Ann Waldhauer, Venkatasubramani Balu, Kieran Mark Tracy
  • Patent number: 10224442
    Abstract: Methods of fabricating solar cell emitter regions with differentiated P-type and N-type regions architectures, and resulting solar cells, are described. In an example, a back contact solar cell can include a substrate having a light-receiving surface and a back surface. A first polycrystalline silicon emitter region of a first conductivity type is disposed on a first thin dielectric layer disposed on the back surface of the substrate. A second polycrystalline silicon emitter region of a second, different, conductivity type is disposed on a second thin dielectric layer disposed on the back surface of the substrate. A third thin dielectric layer is disposed over an exposed outer portion of the first polycrystalline silicon emitter region and is disposed laterally directly between the first and second polycrystalline silicon emitter regions. A first conductive contact structure is disposed on the first polycrystalline silicon emitter region.
    Type: Grant
    Filed: October 26, 2016
    Date of Patent: March 5, 2019
    Assignee: SunPower Corporation
    Inventors: David D. Smith, Timothy Weidman, Scott Harrington, Venkatasubramani Balu
  • Patent number: 10217878
    Abstract: Tri-layer semiconductor stacks for patterning features on solar cells, and the resulting solar cells, are described herein. In an example, a solar cell includes a substrate. A semiconductor structure is disposed above the substrate. The semiconductor structure includes a P-type semiconductor layer disposed directly on a first semiconductor layer. A third semiconductor layer is disposed directly on the P-type semiconductor layer. An outermost edge of the third semiconductor layer is laterally recessed from an outermost edge of the first semiconductor layer by a width. An outermost edge of the P-type semiconductor layer is sloped from the outermost edge of the third semiconductor layer to the outermost edge of the third semiconductor layer. A conductive contact structure is electrically connected to the semiconductor structure.
    Type: Grant
    Filed: April 1, 2016
    Date of Patent: February 26, 2019
    Assignee: SunPower Corporation
    Inventors: Kieran Mark Tracy, David D. Smith, Venkatasubramani Balu, Asnat Masad, Ann Waldhauer
  • Patent number: 10141462
    Abstract: Methods of fabricating solar cell emitter regions with differentiated P-type and N-type region architectures, and the resulting solar cells, are described herein. In an example, a solar cell includes an N-type semiconductor substrate having a light-receiving surface and a back surface. A plurality of N-type polycrystalline silicon regions is disposed on a first thin dielectric layer disposed on the back surface of the N-type semiconductor substrate. A plurality of P-type polycrystalline silicon regions is disposed on a second thin dielectric layer disposed in a corresponding one of a plurality of trenches interleaving the plurality of N-type polycrystalline silicon regions in the back surface of the N-type semiconductor substrate.
    Type: Grant
    Filed: December 19, 2016
    Date of Patent: November 27, 2018
    Assignee: SunPower Corporation
    Inventors: David D. Smith, Ann Waldhauer, Venkatasubramani Balu, Kieran Mark Tracy
  • Publication number: 20180175221
    Abstract: Methods of fabricating solar cell emitter regions with differentiated P-type and N-type region architectures, and the resulting solar cells, are described herein. In an example, a solar cell includes an N-type semiconductor substrate having a light-receiving surface and a back surface. A plurality of N-type polycrystalline silicon regions is disposed on a first thin dielectric layer disposed on the back surface of the N-type semiconductor substrate. A plurality of P-type polycrystalline silicon regions is disposed on a second thin dielectric layer disposed in a corresponding one of a plurality of trenches interleaving the plurality of N-type polycrystalline silicon regions in the back surface of the N-type semiconductor substrate.
    Type: Application
    Filed: December 19, 2016
    Publication date: June 21, 2018
    Inventors: David D. Smith, Ann Waldhauer, Venkatasubramani Balu, Kieran Mark Tracy
  • Patent number: 9837259
    Abstract: A method of processing a silicon substrate can include etching the silicon substrate with a first etchant having a first concentration and etching with a second etchant having a second concentration. In an embodiment, the second concentration of the second etchant can be greater than the first concentration of the first etchant. In one embodiment, the first etchant can be a different type of etchant than the second etchant. In an embodiment, the first and second etchant can be the same type of etchant. In some embodiments the silicon substrate can be cleaned with a first cleaning solution to remove contaminants from the silicon substrate prior to etching with the first etchant. In an embodiment, the silicon substrate can be cleaned with a second cleaning solution after etching the silicon substrate with a second etchant.
    Type: Grant
    Filed: August 29, 2014
    Date of Patent: December 5, 2017
    Assignees: SunPower Corporation, Total Marketing Services
    Inventors: Scott Harrington, Venkatasubramani Balu, Amada Lorena Montesdeoca Santana
  • Publication number: 20170288074
    Abstract: Methods of fabricating solar cell emitter regions with differentiated P-type and N-type regions architectures, and resulting solar cells, are described. In an example, a back contact solar cell can include a substrate having a light-receiving surface and a back surface. A first polycrystalline silicon emitter region of a first conductivity type is disposed on a first thin dielectric layer disposed on the back surface of the substrate. A second polycrystalline silicon emitter region of a second, different, conductivity type is disposed on a second thin dielectric layer disposed on the back surface of the substrate. A third thin dielectric layer is disposed over an exposed outer portion of the first polycrystalline silicon emitter region and is disposed laterally directly between the first and second polycrystalline silicon emitter regions. A first conductive contact structure is disposed on the first polycrystalline silicon emitter region.
    Type: Application
    Filed: October 26, 2016
    Publication date: October 5, 2017
    Inventors: David D. Smith, Timothy Weidman, Scott Harrington, Venkatasubramani Balu
  • Publication number: 20170288070
    Abstract: Tri-layer semiconductor stacks for patterning features on solar cells, and the resulting solar cells, are described herein. In an example, a solar cell includes a substrate. A semiconductor structure is disposed above the substrate. The semiconductor structure includes a P-type semiconductor layer disposed directly on a first semiconductor layer. A third semiconductor layer is disposed directly on the P-type semiconductor layer. An outermost edge of the third semiconductor layer is laterally recessed from an outermost edge of the first semiconductor layer by a width. An outermost edge of the P-type semiconductor layer is sloped from the outermost edge of the third semiconductor layer to the outermost edge of the third semiconductor layer. A conductive contact structure is electrically connected to the semiconductor structure.
    Type: Application
    Filed: April 1, 2016
    Publication date: October 5, 2017
    Inventors: Kieran Mark Tracy, David D. Smith, Venkatasubramani Balu, Asnat Masad, Ann Waldhauer
  • Publication number: 20170222072
    Abstract: Methods of fabricating solar cell emitter regions with differentiated P-type and N-type regions architectures, and resulting solar cells, are described. In an example, a back contact solar cell includes a substrate having a light-receiving surface and a back surface. A first polycrystalline silicon emitter region of a first conductivity type is disposed on a first thin dielectric layer disposed on the back surface of the substrate. A second polycrystalline silicon emitter region of a second, different, conductivity type is disposed on a second thin dielectric layer disposed on the back surface of the substrate. A third thin dielectric layer is disposed laterally directly between the first and second polycrystalline silicon emitter regions. A first conductive contact structure is disposed on the first polycrystalline silicon emitter region. A second conductive contact structure is disposed on the second polycrystalline silicon emitter region.
    Type: Application
    Filed: April 20, 2017
    Publication date: August 3, 2017
    Inventors: Seung Bum Rim, David D. Smith, Taiqing Qiu, Staffan Westerberg, Kieran Mark Tracy, Venkatasubramani Balu
  • Patent number: 9634177
    Abstract: Methods of fabricating solar cell emitter regions with differentiated P-type and N-type regions architectures, and resulting solar cells, are described. In an example, a back contact solar cell includes a substrate having a light-receiving surface and a back surface. A first polycrystalline silicon emitter region of a first conductivity type is disposed on a first thin dielectric layer disposed on the back surface of the substrate. A second polycrystalline silicon emitter region of a second, different, conductivity type is disposed on a second thin dielectric layer disposed on the back surface of the substrate. A third thin dielectric layer is disposed laterally directly between the first and second polycrystalline silicon emitter regions. A first conductive contact structure is disposed on the first polycrystalline silicon emitter region. A second conductive contact structure is disposed on the second polycrystalline silicon emitter region.
    Type: Grant
    Filed: October 21, 2015
    Date of Patent: April 25, 2017
    Assignee: SunPower Corporation
    Inventors: Seung Bum Rim, David D. Smith, Taiqing Qiu, Staffan Westerberg, Kieran Mark Tracy, Venkatasubramani Balu
  • Patent number: 9502601
    Abstract: Methods of fabricating solar cell emitter regions with differentiated P-type and N-type regions architectures, and resulting solar cells, are described. In an example, a back contact solar cell can include a substrate having a light-receiving surface and a back surface. A first polycrystalline silicon emitter region of a first conductivity type is disposed on a first thin dielectric layer disposed on the back surface of the substrate. A second polycrystalline silicon emitter region of a second, different, conductivity type is disposed on a second thin dielectric layer disposed on the back surface of the substrate. A third thin dielectric layer is disposed over an exposed outer portion of the first polycrystalline silicon emitter region and is disposed laterally directly between the first and second polycrystalline silicon emitter regions. A first conductive contact structure is disposed on the first polycrystalline silicon emitter region.
    Type: Grant
    Filed: April 1, 2016
    Date of Patent: November 22, 2016
    Assignee: SunPower Corporation
    Inventors: David D. Smith, Timothy Weidman, Scott Harrington, Venkatasubramani Balu
  • Patent number: 9419166
    Abstract: A method of fabricating a solar cell can include forming a first dopant region over a silicon substrate and an oxide region over the first dopant region. In an embodiment, the oxide region can protect the first dopant region from a first etching process. In an embodiment, a second dopant region can be formed over the silicon substrate, where a mask can be formed to protect a first portion of the second dopant region from the first etching process. In an embodiment, the first etching process can be performed to expose portions of the silicon substrate and/or a silicon region. A second etching process can be performed to form a trench region to separate a first and second doped region of the solar cell. A third etching process can be performed to remove contaminants from the solar cell and remove any remaining portions of the oxide region.
    Type: Grant
    Filed: December 18, 2015
    Date of Patent: August 16, 2016
    Assignee: SunPower Corporation
    Inventors: Scott Harrington, Venkatasubramani Balu, Westerberg Staffan, Peter John Cousins
  • Publication number: 20160111583
    Abstract: A method of fabricating a solar cell can include forming a first dopant region over a silicon substrate and an oxide region over the first dopant region. In an embodiment, the oxide region can protect the first dopant region from a first etching process. In an embodiment, a second dopant region can be formed over the silicon substrate, where a mask can be formed to protect a first portion of the second dopant region from the first etching process. In an embodiment, the first etching process can be performed to expose portions of the silicon substrate and/or a silicon region. A second etching process can be performed to form a trench region to separate a first and second doped region of the solar cell. A third etching process can be performed to remove contaminants from the solar cell and remove any remaining portions of the oxide region.
    Type: Application
    Filed: December 18, 2015
    Publication date: April 21, 2016
    Inventors: Scott Harrington, Venkatasubramani Balu, Westerberg Staffan, Peter John Cousins
  • Publication number: 20160043267
    Abstract: Methods of fabricating solar cell emitter regions with differentiated P-type and N-type regions architectures, and resulting solar cells, are described. In an example, a back contact solar cell includes a substrate having a light-receiving surface and a back surface. A first polycrystalline silicon emitter region of a first conductivity type is disposed on a first thin dielectric layer disposed on the back surface of the substrate. A second polycrystalline silicon emitter region of a second, different, conductivity type is disposed on a second thin dielectric layer disposed on the back surface of the substrate. A third thin dielectric layer is disposed laterally directly between the first and second polycrystalline silicon emitter regions. A first conductive contact structure is disposed on the first polycrystalline silicon emitter region. A second conductive contact structure is disposed on the second polycrystalline silicon emitter region.
    Type: Application
    Filed: October 21, 2015
    Publication date: February 11, 2016
    Inventors: Seung Bum Rim, David D. Smith, Taiqing Qiu, Staffan Westerberg, Kieran Mark Tracy, Venkatasubramani Balu