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).

  • Memristive device based on reversible intercalated ion transfer between two meta-stable phases
    Patent number: 10229736
    Abstract: Memristive devices based on ion-transfer between two meta-stable phases in an ion intercalated material are provided. In one aspect, a memristive device is provided. The memristive device includes: a first inert metal contact; a layer of a phase separated material disposed on the first inert metal contact, wherein the phase separated material includes interstitial ions; and a second inert metal contact disposed on the layer of the phase separated material. The first phase of the phase separated material can have a different concentration of the interstitial ions from the second phase of the phase separated material such that the first phase of the phase separated material has a different electrical conductivity from the second phase of the phase separated material. A method for operating the present memristive device is also provided.
    Type: Grant
    Filed: June 22, 2017
    Date of Patent: March 12, 2019
    Assignee: International Business Machines Corporation
    Inventors: Kevin W. Brew, Talia S. Gershon, Seyoung Kim, Glenn J. Martyna, Dennis M. Newns, Teodor K. Todorov
  • Solution-phase inclusion of silver into chalcogenide semiconductor inks
    Patent number: 10217888
    Abstract: Silver-containing absorbers for photovoltaic devices and techniques for fabrication thereof are provided. In one aspect, a method of forming an ink includes: mixing a silver halide and a solvent to form a first solution; mixing a metal, sulfur, and the solvent to form a second solution; combining the first solution and the second solution to form a precursor solution; and adding constituent components for an absorber material to the precursor solution to form the ink. Methods of forming an absorber film, a photovoltaic device, and the resulting photovoltaic device are also provided.
    Type: Grant
    Filed: October 6, 2016
    Date of Patent: February 26, 2019
    Assignee: International Business Machines Corporation
    Inventors: Priscilla D. Antunez, Talia S. Gershon, Richard A. Haight, Teodor K. Todorov
  • Three-terminal metastable symmetric zero-volt battery memristive device
    Patent number: 10186657
    Abstract: A method of fabricating a memristive structure for symmetric modulation between resistance states is presented. The method includes forming a first electrode and a second electrode over an insulating substrate, forming an anode contacting the first and second electrodes, forming an ionic conductor over the anode, forming a cathode of the same material as the anode over the ionic conductor, forming a third electrode over the cathode, and enabling bidirectional transport of ions between the anode and cathode resulting in a resistance adjustment of the memristive structure, the anode and the cathode being formed from metastable mixed conducting materials with ion concentration dependent conductivity.
    Type: Grant
    Filed: December 5, 2017
    Date of Patent: January 22, 2019
    Assignee: International Business Machines Corporation
    Inventors: Kevin W. Brew, Talia S. Gershon, Seyoung Kim, Dennis M. Newns, Teodor K. Todorov
  • Controllable indium doping for high efficiency CZTS thin-film solar cells
    Patent number: 10177269
    Abstract: A photovoltaic device includes a first contact layer formed on a substrate. An absorber layer includes Cu—Zn—Sn—S(Se) (CZTSSe) on the first contact layer. A buffer layer is formed in contact with the absorber layer. Metal dopants are dispersed in a junction region between the absorber layer and the buffer layer. The metal dopants have a valence between the absorber layer and the buffer layer to increase junction potential. A transparent conductive contact layer is formed over the buffer layer.
    Type: Grant
    Filed: June 24, 2015
    Date of Patent: January 8, 2019
    Assignee: International Business Machines Corporation
    Inventors: Talia S. Gershon, Jeehwan Kim, Yun Seog Lee, Teodor K. Todorov
  • Plasmonic enhancement of absorption in sunscreen applications
    Patent number: 10166176
    Abstract: Zinc oxide compositions as well as techniques for plasmonic enhancement of absorption in sunscreen applications are provided herein. A method includes selecting one or more metal particles to be used in conjunction with one or more zinc oxide particles in a sunscreen composition, wherein said selecting is based on the plasmon resonance frequency associated with each of the metal particles; and embedding the one or more selected metal particles into each of the one or more zinc oxide particles.
    Type: Grant
    Filed: February 16, 2017
    Date of Patent: January 1, 2019
    Assignee: International Business Machines Corporation
    Inventors: Talia S. Gershon, Yun Seog Lee, Ning Li, Devendra Sadana, Teodor K. Todorov
  • Memristive Device Based on Reversible Intercalated Ion Transfer Between Two Meta-Stable Phases
    Publication number: 20180374535
    Abstract: Memristive devices based on ion-transfer between two meta-stable phases in an ion intercalated material are provided. In one aspect, a memristive device is provided. The memristive device includes: a first inert metal contact; a layer of a phase separated material disposed on the first inert metal contact, wherein the phase separated material includes interstitial ions; and a second inert metal contact disposed on the layer of the phase separated material. The first phase of the phase separated material can have a different concentration of the interstitial ions from the second phase of the phase separated material such that the first phase of the phase separated material has a different electrical conductivity from the second phase of the phase separated material. A method for operating the present memristive device is also provided.
    Type: Application
    Filed: June 22, 2017
    Publication date: December 27, 2018
    Inventors: Kevin W. Brew, Talia S. Gershon, Seyoung Kim, Glenn J. Martyna, Dennis M. Newns, Teodor K. Todorov
  • Low Temperature Method of Forming Layered HT-LiCoO2
    Publication number: 20180371617
    Abstract: Low temperature techniques for forming layered lithium cobalt oxide (LCO) are provided. In one aspect, a method of synthesizing layered LCO includes: forming a metal catalyst layer (e.g., platinum) on a substrate; depositing LCO onto the metal catalyst layer; and annealing the LCO under conditions sufficient to form the layered LCO on the metal catalyst layer. An adhesion layer can be deposited on the substrate, and the metal catalyst layer can be deposited onto the adhesion layer. In another aspect, a structure is provided including: a substrate; a metal catalyst layer (e.g., platinum) disposed on the substrate; and layered LCO formed on the metal catalyst layer. An adhesion layer can be disposed between the substrate and the metal catalyst layer.
    Type: Application
    Filed: June 23, 2017
    Publication date: December 27, 2018
    Inventors: Kevin W. Brew, Saurabh Singh, Teodor K. Todorov
  • SOLUTION PROCESS FOR SILVER-CONTAINING CHALCOGENIDE LAYER DEPOSITION
    Publication number: 20180374971
    Abstract: A method of preparing a Ag2ZnSn(S,Se)4 compound, including dissolving selenourea (SeC(NH2)2) in an aprotic solvent, and dissolving a silver salt, a zinc salt, and a tin salt in the aprotic solvent with the selenourea to form a metal solution; and coating the metal solution onto a substrate to form an Ag2ZnSn(S,Se)4 compound layer on the substrate.
    Type: Application
    Filed: April 12, 2018
    Publication date: December 27, 2018
    Inventors: Talia S. Gershon, Richard A. Haight, Saurabh Singh, Teodor K. Todorov
  • Ultraviolet-blocking photovoltaic sunglasses
    Patent number: 10156739
    Abstract: Techniques for integrating photovoltaics into wearables, such as eyewear, are provided. In one aspect, a method of forming a lens for photovoltaic eyewear includes: forming a semitransparent photovoltaic film on at least a portion of a viewable area of the lens, wherein the semitransparent photovoltaic film includes an inorganic absorber material having a band gap of from about 1.4 eV to about 2.2 eV, and ranges therebetween. The semitransparent photovoltaic film can be configured to block greater than about 99.9% UVA, UVB, and UVC light rays, and from about 95% to about 99%, and ranges therebetween, of HEV light rays from passing therethrough. Photovoltaic eyewear formed by the present techniques is also provided.
    Type: Grant
    Filed: February 14, 2017
    Date of Patent: December 18, 2018
    Assignee: International Business Machines Corporation
    Inventors: Douglas M. Bishop, Saurabh Singh, Teodor K. Todorov
  • THREE-TERMINAL METASTABLE SYMMETRIC ZERO-VOLT BATTERY MEMRISTIVE DEVICE
    Publication number: 20180358553
    Abstract: A method of fabricating a memristive structure for symmetric modulation between resistance states is presented. The method includes forming a first electrode and a second electrode over an insulating substrate, forming an anode contacting the first and second electrodes, forming an ionic conductor over the anode, forming a cathode of the same material as the anode over the ionic conductor, forming a third electrode over the cathode, and enabling bidirectional transport of ions between the anode and cathode resulting in a resistance adjustment of the memristive structure, the anode and the cathode being formed from metastable mixed conducting materials with ion concentration dependent conductivity.
    Type: Application
    Filed: December 5, 2017
    Publication date: December 13, 2018
    Inventors: Kevin W. Brew, Talia S. Gershon, Seyoung Kim, Dennis M. Newns, Teodor K. Todorov
  • THREE-TERMINAL METASTABLE SYMMETRIC ZERO-VOLT BATTERY MEMRISTIVE DEVICE
    Publication number: 20180358552
    Abstract: A method of fabricating a memristive structure for symmetric modulation between resistance states is presented. The method includes forming a first electrode and a second electrode over an insulating substrate, forming an anode contacting the first and second electrodes, forming an ionic conductor over the anode, forming a cathode of the same material as the anode over the ionic conductor, forming a third electrode over the cathode, and enabling bidirectional transport of ions between the anode and cathode resulting in a resistance adjustment of the memristive structure, the anode and the cathode being formed from metastable mixed conducting materials with ion concentration dependent conductivity.
    Type: Application
    Filed: June 7, 2017
    Publication date: December 13, 2018
    Inventors: Kevin W. Brew, Talia S. Gershon, Seyoung Kim, Dennis M. Newns, Teodor K. Todorov
  • Aqueous-based method of forming semiconductor film and photovoltaic device including the film
    Patent number: 10147604
    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: Grant
    Filed: March 5, 2010
    Date of Patent: December 4, 2018
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: David B. Mitzi, Teodor K. Todorov
  • Precision dual annealing apparatus
    Patent number: 10126053
    Abstract: A dual annealing apparatus and use thereof for precision annealing of an article are provided. In one aspect, an annealing apparatus includes: a first heating plate opposite a second heating plate; a first cooling source associated with the first heating plate; and a second cooling source associated with the second heating plate, wherein the first heating plate and the second heating plate are independently controllable, and wherein the first cooling source and the second cooling source are independently controllable. A method for annealing an article using the annealing apparatus is also provided.
    Type: Grant
    Filed: September 2, 2016
    Date of Patent: November 13, 2018
    Assignee: International Business Machines Corporation
    Inventor: Teodor K. Todorov
  • Chalcogen Back Surface Field Layer
    Publication number: 20180294368
    Abstract: Kesterite photovoltaic devices having a back surface field layer are provided. In one aspect, a method of forming a photovoltaic device includes: forming a complete photovoltaic device having a substrate, an electrically conductive layer on the substrate, an absorber layer on the electrically conductive layer, a buffer layer on the absorber layer, and a transparent front contact on the buffer layer; removing the substrate and the electrically conductive layer from the complete photovoltaic device to expose a backside surface of the absorber layer; forming a passivating layer on the backside surface of the absorber layer; and forming a high work function back contact on the passivating layer. A photovoltaic device having a passivating layer is also provided.
    Type: Application
    Filed: June 14, 2018
    Publication date: October 11, 2018
    Inventors: Priscilla D. Antunez, Bruce A. Ek, Richard A. Haight, Ravin Mankad, Saurabh Singh, Teodor K. Todorov
  • Anneal techniques for chalcogenide semiconductors
    Patent number: 10096738
    Abstract: Techniques for precisely controlling the composition of volatile components (such as sulfur (S), selenium (Se), and tin (Sn)) of chalcogenide semiconductors in real-time—during production of the material are provided. In one aspect, a method for forming a chalcogenide semiconductor material includes providing a S source(s) and a Se source(s); heating the S source(s) to form a S-containing vapor; heating the Se source(s) to form a Se-containing vapor; passing a carrier gas first through the S-containing vapor and then through the Se-containing vapor, wherein the S-containing vapor and the Se-containing vapor are transported via the carrier gas to a sample; and contacting the S-containing vapor and the Se-containing vapor with the sample under conditions sufficient to form the chalcogenide semiconductor material. A multi-chamber processing apparatus is also provided.
    Type: Grant
    Filed: November 13, 2017
    Date of Patent: October 9, 2018
    Assignee: International Business Machines Corporation
    Inventors: Sunit S. Mahajan, Teodor K. Todorov
  • Plasmonic enhancement of absorption in sunscreen applications
    Patent number: 10092487
    Abstract: Zinc oxide compositions as well as techniques for plasmonic enhancement of absorption in sunscreen applications are provided herein. A method includes selecting one or more metal particles to be used in conjunction with one or more zinc oxide particles in a sunscreen composition, wherein said selecting is based on the plasmon resonance frequency associated with each of the metal particles; and embedding the one or more selected metal particles into each of the one or more zinc oxide particles.
    Type: Grant
    Filed: April 29, 2016
    Date of Patent: October 9, 2018
    Assignee: International Business Machines Corporation
    Inventors: Talia S. Gershon, Yun Seog Lee, Ning Li, Devendra Sadana, Teodor K. Todorov
  • Shell-structured particles for sunscreen applications
    Patent number: 10076475
    Abstract: Shell-structured particles for sunscreen applications are provided herein. A method includes selecting one or more particles to serve as a core material in a sunscreen composition, wherein each of the one or more particles comprises a band gap within a predetermined range, and wherein said selecting is based on a desired absorption spectrum of the sunscreen composition; coating the one or more particles with at least one layer of zinc oxide. A composition includes selecting one or more particles to serve as a coating layer in a sunscreen composition, wherein each of the one or more particles comprises a band gap within a predetermined range, and wherein said selecting is based on a desired absorption spectrum of the sunscreen composition; and coating one or more zinc oxide particles with the one or more selected particles.
    Type: Grant
    Filed: April 29, 2016
    Date of Patent: September 18, 2018
    Assignee: International Business Machines Corporation
    Inventors: Talia S. Gershon, Yun Seog Lee, Ning Li, Devendra Sadana, Teodor K. Todorov
  • ATOMIC LAYER DEPOSITION FOR PHOTOVOLTAIC DEVICES
    Publication number: 20180261711
    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: May 10, 2018
    Publication date: September 13, 2018
    Inventors: JEEHWAN KIM, DAVID B. MITZI, BYUNGHA SHIN, TEODOR K. TODOROV, MARK T. WINKLER
  • ATOMIC LAYER DEPOSITION FOR PHOTOVOLTAIC DEVICES
    Publication number: 20180261710
    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: May 10, 2018
    Publication date: September 13, 2018
    Inventors: JEEHWAN KIM, DAVID B. MITZI, BYUNGHA SHIN, TEODOR K. TODOROV, MARK T. WINKLER
  • Ultraviolet-Blocking Photovoltaic Sunglasses
    Publication number: 20180231804
    Abstract: Techniques for integrating photovoltaics into wearables, such as eyewear, are provided. In one aspect, a method of forming a lens for photovoltaic eyewear includes: forming a semitransparent photovoltaic film on at least a portion of a viewable area of the lens, wherein the semitransparent photovoltaic film includes an inorganic absorber material having a band gap of from about 1.4 eV to about 2.2 eV, and ranges therebetween. The semitransparent photovoltaic film can be configured to block greater than about 99.9% UVA, UVB, and UVC light rays, and from about 95% to about 99%, and ranges therebetween, of HEV light rays from passing therethrough. Photovoltaic eyewear formed by the present techniques is also provided.
    Type: Application
    Filed: February 14, 2017
    Publication date: August 16, 2018
    Inventors: Douglas M. Bishop, Saurabh Singh, Teodor K. Todorov