Patents by Inventor Teodor K. Todorov

Teodor K. Todorov 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: 9252304
    Abstract: Methods for depositing a kesterite film comprising a compound of the formula: Cu2?xZn1+ySn(S1?zSez)4+q, wherein 0?x?1; 0?y?1; 0?z?1; ?1?q?1, generally include contacting a hydrazine-based solvent, a source of Cu, a source of Sn, a source of Zn carboxylate, a source of at least one of S and Se, under conditions sufficient to form a solution substantially free of solid particles; applying the solution onto a substrate to form a thin layer; and annealing the thin layer at a temperature, pressure, and length of time sufficient to form the kesterite film. Also disclosed are hydrazine-based precursor solutions for forming a kesterite film and a photovoltaic device including the kesterite film formed by the above method.
    Type: Grant
    Filed: October 4, 2012
    Date of Patent: February 2, 2016
    Assignee: International Business Machines Corporation
    Inventor: Teodor K. Todorov
  • Publication number: 20150377702
    Abstract: In one aspect, a spectrometer insert is provided. The spectrometer insert includes: an enclosed housing; a first transparent window on a first side of the enclosed housing; a second transparent window on a second side of the enclosed housing, wherein the first side and the second side are opposing sides of the enclosed housing; and a sample mounting and heating assembly positioned within an interior cavity of the enclosed housing in between, and in line of sight of, the first transparent window and the second transparent window. A method for using the spectrometer insert to locally heat a sample so as to measure temperature-dependent optical properties of the sample is also provided.
    Type: Application
    Filed: June 27, 2014
    Publication date: December 31, 2015
    Inventors: Nestor A. Bojarczuk, Talia S. Gershon, Teodor K. Todorov, Theodore G. van Kessel
  • Publication number: 20150340536
    Abstract: A photovoltaic device and method include a substrate, a conductive layer formed on the substrate and an absorber layer formed on the conductive layer from a Cu—Zn—Sn containing chalcogenide material. An emitter layer is formed on the absorber layer and a buffer layer is formed on the emitter layer including an atomic layer deposition (ALD) layer. A transparent conductor layer is formed on the buffer layer.
    Type: Application
    Filed: August 5, 2015
    Publication date: November 26, 2015
    Inventors: JEEHWAN KIM, DAVID B. MITZI, BYUNGHA SHIN, TEODOR K. TODOROV, MARK T. WINKLER
  • Patent number: 9153729
    Abstract: A photovoltaic device and method include a substrate, a conductive layer formed on the substrate and an absorber layer formed on the conductive layer from a Cu—Zn—Sn containing chalcogenide material. An emitter layer is formed on the absorber layer and a buffer layer is formed on the emitter layer including an atomic layer deposition (ALD) layer. A transparent conductor layer is formed on the buffer layer.
    Type: Grant
    Filed: November 26, 2012
    Date of Patent: October 6, 2015
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Jeehwan Kim, David B. Mitzi, Byungha Shin, Teodor K. Todorov, Mark T. Winkler
  • Publication number: 20150263199
    Abstract: A photosensitive device and method includes a top cell having an N-type layer, a P-type layer and a top intrinsic layer therebetween. A bottom cell includes an N-type layer, a P-type layer and a bottom intrinsic layer therebetween. The bottom intrinsic layer includes a Cu—Zn—Sn containing chalcogenide.
    Type: Application
    Filed: June 1, 2015
    Publication date: September 17, 2015
    Inventors: OKI GUNAWAN, JEEHWAN KIM, DAVID B. MITZI, DEVENDRA K. SADANA, TEODOR K. TODOROV
  • Publication number: 20150144177
    Abstract: Methods for depositing a kesterite film comprising a compound of the formula: Cu2?xZn1+ySn(S1?zSez)4+q, wherein 0?x?1; 0?y?1; 0?z?1; ?1?q?1, generally include contacting a hydrazine-based solvent, a source of Cu, a source of Sn, a source of Zn carboxylate, a source of at least one of S and Se, under conditions sufficient to form a solution substantially free of solid particles; applying the solution onto a substrate to form a thin layer; and annealing the thin layer at a temperature, pressure, and length of time sufficient to form the kesterite film. Also disclosed are hydrazine-based precursor solutions for forming a kesterite film and a photovoltaic device including the kesterite film formed by the above method.
    Type: Application
    Filed: January 29, 2015
    Publication date: May 28, 2015
    Inventor: Teodor K. Todorov
  • Publication number: 20150135994
    Abstract: Methods for depositing a kesterite film comprising a compound of the formula: Cu2-xZn1+ySn(S1-zSez)4+q, wherein 0?x?1; 0<y?1; 0?z?1; ?1?q?1, generally include contacting a hydrazine-based solvent, a source of Cu, a source of Sn, a source of Zn carboxylate, a source of at least one of S and Se, under conditions sufficient to form a solution substantially free of solid particles; applying the solution onto a substrate to form a thin layer; and annealing the thin layer at a temperature, pressure, and length of time sufficient to form the kesterite film. Also disclosed are hydrazine-based precursor solutions for forming a kesterite film and a photovoltaic device including the kesterite film formed by the above method.
    Type: Application
    Filed: January 29, 2015
    Publication date: May 21, 2015
    Inventor: Teodor K. Todorov
  • Patent number: 8765518
    Abstract: Improved chalcogenide solutions are provided. In one aspect, a method of forming an aqueous selenium-containing solution is provided. The method includes the following step. Water, ammonium hydroxide, elemental selenium, and elemental aluminum are contacted under conditions sufficient to form the aqueous selenium-containing solution. The conditions may include sonication for a period of time of from about 1 minute to about 10 minutes and/or stirring for a period of time of from about 10 minutes to about 72 hours at a temperature of from about 20° C. to about 25° C. A method of fabricating a photovoltaic device is also provided.
    Type: Grant
    Filed: March 12, 2013
    Date of Patent: July 1, 2014
    Assignee: International Business Machines Corporation
    Inventor: Teodor K. Todorov
  • Publication number: 20140147958
    Abstract: A photovoltaic device and method include a substrate, a conductive layer formed on the substrate and an absorber layer formed on the conductive layer from a Cu—Zn—Sn containing chalcogenide material. An emitter layer is formed on the absorber layer and a buffer layer is formed on the emitter layer including an atomic layer deposition (ALD) layer. A transparent conductor layer is formed on the buffer layer.
    Type: Application
    Filed: August 14, 2013
    Publication date: May 29, 2014
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Jeehwan Kim, David B. Mitzi, Byungha Shin, Teodor K. Todorov, Mark T. Winkler
  • Publication number: 20140144497
    Abstract: A photovoltaic device and method include a substrate, a conductive layer formed on the substrate and an absorber layer formed on the conductive layer from a Cu—Zn—Sn containing chalcogenide material. An emitter layer is formed on the absorber layer and a buffer layer is formed on the emitter layer including an atomic layer deposition (ALD) layer. A transparent conductor layer is formed on the buffer layer.
    Type: Application
    Filed: November 26, 2012
    Publication date: May 29, 2014
    Applicant: International Business Machines Corporation
    Inventors: Jeehwan Kim, David B. Mitzi, Byungha Shin, Teodor K. Todorov, Mark T. Winkler
  • Publication number: 20140124011
    Abstract: Low-temperature sulfurization/selenization heat treatment processes for photovoltaic devices are provided. In one aspect, a method for fabricating a photovoltaic device is provided. The method includes the following steps. A substrate is provided that is either (i) formed from an electrically conductive material or (ii) coated with at least one layer of a conductive material. A chalcogenide absorber layer is formed on the substrate. A buffer layer is formed on the absorber layer. A transparent front contact is formed on the buffer layer. The device is contacted with a chalcogen-containing vapor having a sulfur and/or selenium compound under conditions sufficient to improve device performance by filling chalcogen vacancies within the absorber layer or the buffer layer or by passivating one or more of grain boundaries in the absorber layer, an interface between the absorber layer and the buffer layer and an interface between the absorber layer and the substrate.
    Type: Application
    Filed: January 13, 2014
    Publication date: May 8, 2014
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: David B. Mitzi, Teodor K. Todorov
  • Publication number: 20140096826
    Abstract: Methods for depositing a kesterite film comprising a compound of the formula: Cu2?xZn1+ySn(S1?zSez)4+q, wherein 0?x?1; 0?y?1; 0?z?1; ?1?q?1, generally include contacting a hydrazine-based solvent, a source of Cu, a source of Sn, a source of Zn carboxylate, a source of at least one of S and Se, under conditions sufficient to form a solution substantially free of solid particles; applying the solution onto a substrate to form a thin layer; and annealing the thin layer at a temperature, pressure, and length of time sufficient to form the kesterite film. Also disclosed are hydrazine-based precursor solutions for forming a kesterite film and a photovoltaic device including the kesterite film formed by the above method.
    Type: Application
    Filed: October 4, 2012
    Publication date: April 10, 2014
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventor: Teodor K. Todorov
  • Patent number: 8617915
    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: Grant
    Filed: June 3, 2011
    Date of Patent: December 31, 2013
    Assignee: International Business Machines Corporation
    Inventors: Supratik Guha, David B. Mitzi, Teodor K. Todorov, Kejia Wang
  • Publication number: 20120279565
    Abstract: A method of depositing a kesterite film which includes a compound of the formula: Cu2?xZn1+ySn(S1?zSez)4+q, wherein 0?x?1; 0?y?1; 0?z?1; ?1?q?1. The method includes contacting hydrazine, a source of Cu, and a source of at least one of S and Se forming solution A; contacting hydrazine, a source of Sn, a source of at least one of S and Se, and a source of Zn forming dispersion B; mixing solution A and dispersion B under conditions sufficient to form a dispersion which includes Zn-containing solid particles; applying the dispersion onto a substrate to form a thin layer of the dispersion on the substrate; and annealing at a temperature, pressure, and length of time sufficient to form the kesterite film. An annealing composition and a photovoltaic device including the kesterite film formed by the above method are also provided.
    Type: Application
    Filed: July 18, 2012
    Publication date: November 8, 2012
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: David B. Mitzi, Teodor K. Todorov
  • Publication number: 20120222730
    Abstract: A photosensitive device and method includes a top cell having an N-type layer, a P-type layer and a top intrinsic layer therebetween. A bottom cell includes an N-type layer, a P-type layer and a bottom intrinsic layer therebetween. The bottom intrinsic layer includes a Cu—Zn—Sn containing chalcogenide.
    Type: Application
    Filed: March 1, 2011
    Publication date: September 6, 2012
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Oki Gunawan, Jeehwan Kim, David B. Mitzi, Devendra K. Sadana, Teodor K. Todorov
  • 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
  • Publication number: 20110097496
    Abstract: A method with enhanced safety characteristics of depositing a kesterite film, which includes a compound of the formula: Cu2?xZn1+ySn(S1?zSez)4+q, wherein 0?x?1; 0?y?1; 0?z?1; ?1?q?1. The method includes contacting an aqueous solvent, ammonia, a source of hydrazine, a source of Cu, a source of Sn, a source of Zn, a source of at least one of S and Se, under conditions sufficient to form an aqueous dispersion which includes solid particles; applying the dispersion onto a substrate to form a thin layer of the dispersion on the substrate; and annealing at a temperature, pressure, and length of time sufficient to form the kesterite film. An annealing composition and a photovoltaic device including the kesterite film formed by the above method are also provided.
    Type: Application
    Filed: March 5, 2010
    Publication date: April 28, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: David B. Mitzi, Teodor K. Todorov
  • Publication number: 20110094557
    Abstract: A method of depositing a kesterite film which includes a compound of the formula: Cu2?xZn1+ySn(S1?zSez)4+q, wherein 0?x?1; 0?y?1; 0?z?1; ?1?q?1. The method includes contacting hydrazine, a source of Cu, and a source of at least one of S and Se forming solution A; contacting hydrazine, a source of Sn, a source of at least one of S and Se, and a source of Zn forming dispersion B; mixing solution A and dispersion B under conditions sufficient to form a dispersion which includes Zn-containing solid particles; applying the dispersion onto a substrate to form a thin layer of the dispersion on the substrate; and annealing at a temperature, pressure, and length of time sufficient to form the kesterite film. An annealing composition and a photovoltaic device including the kesterite film formed by the above method are also provided.
    Type: Application
    Filed: October 27, 2009
    Publication date: April 28, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: David B. Mitzi, Teodor K. Todorov