Patents by Inventor Virendra V. Rana

Virendra V. Rana 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: 9455362
    Abstract: Methods for laser irradiation aluminum doping for monocrystalline silicon substrates are provided. According to one aspect of the disclosed subject matter, aluminum metal contacts are formed directly on a surface of a monocrystalline silicon substrate. The aluminum metal contact is selectively heated via laser irradiation, thereby causing the aluminum and a portion of the monocrystalline silicon substrate in proximity to the aluminum to reach a temperature sufficient to allow at least a portion of the silicon to dissolve in the aluminum. The aluminum and the portion of the monocrystalline silicon substrate in proximity to the aluminum is allowed to cool, thereby forming an aluminum-rich doped silicon layer on the monocrystalline silicon substrate.
    Type: Grant
    Filed: December 30, 2011
    Date of Patent: September 27, 2016
    Assignee: Solexel, Inc.
    Inventors: Mehrdad M. Moslehi, Virendra V. Rana, Pranav Anbalagan
  • Patent number: 9419165
    Abstract: A method for making a back contact solar cell. Base isolation regions are formed in a crystalline silicon back contact solar cell substrate having a substrate thickness in the range of approximately 1 micron to 100 microns. Pulsed laser ablation of a substance on the crystalline silicon back contact solar cell substrate is performed to form base openings, wherein the substance is at least one of silicon oxide, silicon nitride, aluminum oxide, silicon oxynitride, or silicon carbide. Emitter regions are selectively doped and base regions are selectively doped. Contact openings are formed for the selectively doped base regions and the selectively doped emitter regions. Metallization is formed on the selectively doped base regions and the selectively doped emitter regions.
    Type: Grant
    Filed: March 18, 2013
    Date of Patent: August 16, 2016
    Assignee: Solexel, Inc.
    Inventors: Virendra V. Rana, JianJun Liang, Pranav Anbalagan, Mehrdad M. Moslehi
  • Publication number: 20160190366
    Abstract: Fabrication methods and structures are provided for the formation of monolithically isled back contact back junction solar cells. In one embodiment, base and emitter contact metallization is formed on the backside of a back contact back junction solar cell substrate. A trench stop layer is formed on the backside of a back contact back junction solar cell substrate and is electrically isolated from the base and emitter contact metallization. The trench stop layer has a pattern for forming a plurality semiconductor regions. An electrically insulating layer is formed on the base and emitter contact metallization and the trench stop layer. A trench isolation pattern is formed through the back contact back junction solar cell substrate to the trench stop layer which partitions the semiconductor layer into a plurality of solar cell semiconductor regions on the electrically insulating layer.
    Type: Application
    Filed: September 4, 2015
    Publication date: June 30, 2016
    Inventors: Mehrdad M. Moslehi, Virendra V. Rana, Heather Deshazer, Pawan Kapur
  • Patent number: 9379258
    Abstract: Fabrication methods for making back contact back junction solar cells. A base dopant source, a field emitter dopant source, and an emitter dopant source are deposited on the back surface of a solar cell substrate. The solar cell substrate is annealed forming emitter contact regions corresponding to the emitter dopant source, field emitter regions corresponding to the field emitter dopant, and base contact regions corresponding to the base dopant source. The base dopant source, field emitter dopant source, and the emitter dopant source are etched. A backside passivation layer is deposited on the back surface of the solar cell. Contacts are opened to the emitter contact regions and the base contact regions through the backside passivation layer. Patterned base metallization and patterned emitter metallization is formed on the back surface of the solar cell with electrical interconnections to the base contact regions and the emitter contact regions.
    Type: Grant
    Filed: September 22, 2014
    Date of Patent: June 28, 2016
    Assignee: Solexel, Inc.
    Inventors: Pawan Kapur, Anand Deshpande, Virendra V. Rana, Mehrdad M. Moslehi, Sean M. Seutter
  • Patent number: 9318644
    Abstract: A back contact back junction thin-film solar cell is formed on a thin-film semiconductor solar cell. Preferably the thin film semiconductor material comprises crystalline silicon. Base regions, emitter regions, and front surface field regions are formed through ion implantation and annealing processes.
    Type: Grant
    Filed: May 29, 2012
    Date of Patent: April 19, 2016
    Assignee: Solexel, Inc.
    Inventors: Mehrdad M. Moslehi, Virendra V. Rana, Pawan Kapur
  • Publication number: 20160093763
    Abstract: The laser patterning methods utilizing a laser absorbent hard mask in combination with wet etching to form patterned solar cell doped regions which may further improve cell efficiency by completely avoiding laser ablation of an underlying semiconductor substrate associated with ablation of an overlying transparent passivation layer.
    Type: Application
    Filed: April 29, 2014
    Publication date: March 31, 2016
    Inventors: Virendra V. Rana, Pawan Kapur, Sean M. Seutter, Mehrdad M. Moslehi
  • Publication number: 20160013335
    Abstract: Fabrication methods and structures relating to backplanes for back contact solar cells that provide for solar cell substrate reinforcement and electrical interconnects are described. The method comprises depositing an interdigitated pattern of base electrodes and emitter electrodes on a backside surface of a semiconductor substrate, attaching a prepreg backplane to the interdigitated pattern of base electrodes and emitter electrodes, forming holes in the prepreg backplane which provide access to the first layer of electrically conductive metal, and depositing a second layer of electrically conductive metal on the backside surface of the prepreg backplane forming an electrical interconnect with the first layer of electrically conductive metal through the holes in the prepreg backplane.
    Type: Application
    Filed: February 5, 2015
    Publication date: January 14, 2016
    Inventors: Mehrdad M. Moslehi, Karl-Josef Kramer, Sean M. Seutter, Pawan Kapur, Thom Stalcup, David Xuan-Qi Wang, George D. Kamian, Kamran Manteghi, Yen-Sheng Su, Pranav Anbalagan, Virendra V. Rana, Anthony Calcaterra, Gerry Olsen, Wojciech Worwag
  • Patent number: 9236510
    Abstract: A method for making an ablated electrically insulating layer on a semiconductor substrate. A first relatively thin layer of at least an undoped glass or undoped oxide is deposited on a surface of a semiconductor substrate having n-type doping. A first relatively thin semiconductor layer having at least one substance chosen from amorphous semiconductor, nanocrystalline semiconductor, microcrystalline semiconductor, or polycrystalline semiconductor is deposited on the relatively thin layer of at least an undoped glass or undoped oxide. At least a layer of borosilicate glass or borosilicate/undoped glass stack is deposited on the relatively thin semiconductor layer. The at least borosilicate glass or borosilicate/undoped glass stack is selectively ablated with a pulsed laser, and the relatively thin semiconductor layer substantially protects the semiconductor substrate from the pulsed laser.
    Type: Grant
    Filed: December 20, 2013
    Date of Patent: January 12, 2016
    Assignee: Solexel, Inc.
    Inventors: Mehrdad M. Moslehi, Virendra V. Rana, Pranav Anbalagan, Vivek Saraswat
  • Patent number: 9214585
    Abstract: Annealing solutions providing damage-free laser patterning utilizing auxiliary heating to anneal laser damaged ablation regions are provided herein. Ablation spots on an underlying semiconductor substrate are annealed during or after pulsed laser ablation patterning of overlying transparent passivation layers.
    Type: Grant
    Filed: April 29, 2014
    Date of Patent: December 15, 2015
    Assignee: Solexel, Inc.
    Inventors: Virendra V. Rana, Mehrdad M. Moslehi, Pawan Kapur, Benjamin Rattle, Heather Deshazer, Solene Coutant
  • Patent number: 9196759
    Abstract: Back contact back junction solar cell and methods for manufacturing are provided. The back contact back junction solar cell comprises a substrate having a light capturing frontside surface with a passivation layer, a doped base region, and a doped backside emitter region with a polarity opposite the doped base region. A backside passivation layer and patterned reflective layer on the emitter form a light trapping backside mirror. An interdigitated metallization pattern is positioned on the backside of the solar cell and a permanent reinforcement provides support to the cell.
    Type: Grant
    Filed: February 23, 2015
    Date of Patent: November 24, 2015
    Assignee: Solexel, Inc.
    Inventors: Mehrdad M. Moslehi, Pawan Kapur, Karl-Josef Kramer, David Xuan-Qi Wang, Sean M. Seutter, Virendra V. Rana, Anthony Calcaterra, Emmanuel Van Kerschaver
  • Publication number: 20150311378
    Abstract: The present application provides effective and efficient structures and methods for the formation of solar cell base and emitter regions and passivation layers using laser processing. Laser absorbent passivation materials are formed on a solar cell substrate and patterned using laser ablation to form base and emitter regions. Laser damage to the solar cell substrate is removed using an etch.
    Type: Application
    Filed: February 26, 2015
    Publication date: October 29, 2015
    Inventors: Pawan Kapur, Anand Deshpande, Sean M. Seutter, Heather Deshazer, Virendra V. Rana, Solene Coutant, Swaroop Kommera, Mehrdad M. Moslehi
  • Patent number: 9130076
    Abstract: Fabrication methods and structures are provided for the formation of monolithically isled back contact back junction solar cells. In one embodiment, base and emitter contact metallization is formed on the backside of a back contact back junction solar cell substrate. A trench stop layer is formed on the backside of a back contact back junction solar cell substrate and is electrically isolated from the base and emitter contact metallization. The trench stop layer has a pattern for forming a plurality semiconductor regions. An electrically insulating layer is formed on the base and emitter contact metallization and the trench stop layer. A trench isolation pattern is formed through the back contact back junction solar cell substrate to the trench stop layer which partitions the semiconductor layer into a plurality of solar cell semiconductor regions on the electrically insulating layer.
    Type: Grant
    Filed: January 20, 2015
    Date of Patent: September 8, 2015
    Assignee: Solexel, Inc.
    Inventors: Mehrdad M. Moslehi, Virendra V. Rana, Heather Deshazer, Pawan Kapur
  • Publication number: 20150243814
    Abstract: Back contact back junction solar cell and methods for manufacturing are provided. The back contact back junction solar cell comprises a substrate having a light capturing frontside surface with a passivation layer, a doped base region, and a doped backside emitter region with a polarity opposite the doped base region. A backside passivation layer and patterned reflective layer on the emitter form a light trapping backside mirror. An interdigitated metallization pattern is positioned on the backside of the solar cell and a permanent reinforcement provides support to the cell.
    Type: Application
    Filed: February 23, 2015
    Publication date: August 27, 2015
    Inventors: Mehrdad M. Moslehi, Pawan Kapur, Karl-Josef Kramer, David Xuan-Qi Wang, Sean M. Seutter, Virendra V. Rana, Anthony Calcaterra, Emmanuel Van Kerschaver
  • Publication number: 20150221792
    Abstract: Fabrication methods for forming self aligned contacts for back contact solar cells are provided.
    Type: Application
    Filed: December 23, 2014
    Publication date: August 6, 2015
    Inventors: Anand Deshpande, Pawan Kapur, Mehrdad M. Moslehi, Virendra V. Rana, Sean M. Seutter
  • Publication number: 20150171230
    Abstract: Fabrication methods for forming thin film back contact solar cells are provided.
    Type: Application
    Filed: September 22, 2014
    Publication date: June 18, 2015
    Inventors: Pawan Kapur, Anand Deshpande, Virendra V. Rana, Mehrdad M. Moslehi, Sean M. Seutter
  • Publication number: 20150171240
    Abstract: According to one aspect of the disclosed subject matter, a method for forming a monolithically isled back contact back junction solar cell using bulk wafers is provided.
    Type: Application
    Filed: September 22, 2014
    Publication date: June 18, 2015
    Inventors: Pawan Kapur, Anand Deshpande, Virendra V. Rana, Mehrdad M. Moslehi, Sean M. Seutter
  • Publication number: 20150162486
    Abstract: The present application provides effective and efficient structures and methods for the formation of solar cell base and emitter regions using laser processing. Laser absorbent passivation materials are formed on a solar cell substrate and patterned using laser ablation to form base and emitter regions.
    Type: Application
    Filed: September 16, 2014
    Publication date: June 11, 2015
    Inventors: Heather Deshazer, Virendra V. Rana, Sean M. Seutter, Pawan Kapur, Mehrdad M. Moslehi, Solene Coutant
  • Publication number: 20150162487
    Abstract: The present application provides effective and efficient structures and methods for the formation of solar cell base and emitter regions and passivation layers using laser processing. Laser absorbent passivation materials are formed on a solar cell substrate and patterned using laser ablation to form base and emitter regions.
    Type: Application
    Filed: December 1, 2014
    Publication date: June 11, 2015
    Inventors: Heather Deshazer, Virendra V. Rana, Sean M. Seutter, Pawan Kapur, Mehrdad M. Moslehi, Solene Coutant
  • Publication number: 20150136227
    Abstract: Fabrication methods and structures are provided for the formation of monolithically isled back contact back junction solar cells. In one embodiment, base and emitter contact metallization is formed on the backside of a back contact back junction solar cell substrate. A trench stop layer is formed on the backside of a back contact back junction solar cell substrate and which is electrically isolated from the base and emitter contact metallization. The trench stop layer has a pattern for forming a plurality semiconductor regions. An electrically insulating layer is formed on the base and emitter contact metallization and the etch stop layer. And a trench isolation pattern is formed through the back contact back junction solar cell substrate to the trench stop layer which partitions semiconductor layer into a plurality of solar cell semiconductor regions on the electrically insulating layer.
    Type: Application
    Filed: January 20, 2015
    Publication date: May 21, 2015
    Inventors: Mehrdad M. Moslehi, Virendra V. Rana, Heather Deshazer, Pawan Kapur
  • Publication number: 20150140721
    Abstract: Various laser processing schemes are disclosed for producing various types of hetero junction and homo-junction solar cells. The methods include base and emitter contact opening, selective doping, metal ablation, annealing to improve passivation, and selective emitter doping via laser heating of aluminum. Also, laser processing schemes are disclosed that are suitable for selective amorphous silicon ablation and selective doping for hetero junction solar cells. Laser ablation techniques are disclosed that leave the underlying silicon substantially undamaged. These laser processing techniques may be applied to semiconductor substrates, including crystalline silicon substrates, and further including crystalline silicon substrates which are manufactured either through wire saw wafering methods or via epitaxial deposition processes, or other cleavage techniques such as ion implantation and heating, that are either planar or textured/three-dimensional.
    Type: Application
    Filed: December 20, 2013
    Publication date: May 21, 2015
    Applicant: SOLEXEL, INC.
    Inventors: Mehrdad M. Moslehi, Virendra V. Rana, Pranav Anbalagan, Vivek Saraswat