Patents by Inventor John Kouvetakis

John Kouvetakis 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: 8821635
    Abstract: Si—Ge materials are grown on Si(100) with Ge-rich contents (Ge>50 at. %) and precise stoichiometries SiGe, SiGe2, SiGe3 and SiGe4. New hydrides with direct Si—Ge bonds derived from the family of compounds (H3Ge)xSiH4-x (x=1-4) are used to grow uniform, relaxed, and highly planar films with low defect densities at unprecedented low temperatures between about 300-450° C. At about 500-700° C., SiGex quantum dots are grown with narrow size distribution, defect-free microstructures and highly homogeneous elemental content at the atomic level. The method provides for precise control of morphology, composition, structure and strain. The grown materials possess the required characteristics for high frequency electronic and optical applications, and for templates and buffer layers for high mobility Si and Ge channel devices.
    Type: Grant
    Filed: April 8, 2005
    Date of Patent: September 2, 2014
    Assignee: Arizona Board of Regents on Behalf of Arizona State University
    Inventors: John Kouvetakis, Ignatius S. T. Tsong, Changwu Hu, John Tolle
  • Patent number: 8803194
    Abstract: Semiconductor structures are provided comprising a substrate and a epitaxial layer formed over the substrate, wherein the epitaxial layer comprises B; and one or more element selected from the group consisting of Zr, Hf and Al and has a thickness greater than 50 nm. Further, methods for integrating Group III nitrides onto a substrate comprising, forming an epitaxial buffer layer of a diboride of Zr, Hf, Al, or mixtures thereof, over a substrate; and forming a Group III nitride layer over the buffer layer, are provided which serve to thermally decouple the buffer layer from the underlying substrate, thereby greatly reducing the strain induced in the semiconductor structures upon fabrication and/or operation.
    Type: Grant
    Filed: January 4, 2008
    Date of Patent: August 12, 2014
    Assignee: Arizona Board of Regents, a body corporate of the State of Arizona Acting for and on Behalf of Arizona State University
    Inventors: John Kouvetakis, Radek Roucka
  • Publication number: 20130313579
    Abstract: Detectors based on such Ge(Sn) alloys of the formula Ge1-xSnx (e.g., 0<x<0.01) have increased responsivity while keeping alloy scattering to a minimum. Such small amounts of Sn are also useful for improving the performance of the recently demonstrated Ge-on-Si laser structures, since the addition of Sn monotonically reduces the separation between the direct and indirect minima in the conduction band of Ge. Thus, provided herein are Ge(Sn) alloys of the formula Ge1xSnx, wherein x is less than 0.01, wherein the alloy is optionally n-doped or p-doped; and assemblies and photodiodes comprising the same, and methods for their formation.
    Type: Application
    Filed: November 18, 2011
    Publication date: November 28, 2013
    Inventors: John Kouvetakis, Richard Beeler, Jose Menendez, Radek Roucka
  • Patent number: 8568681
    Abstract: A method is provided for synthesizing silicon-germanium hydride compounds of the formula (H3Ge)4-xSiHx, wherein x=0, 1, 2 or 3. The method includes combining a silane triflate with a compound having a GeH3 ligand under conditions whereby the silicon-germanium hydride is formed. The compound having the GeH3 ligand is selected from the group consisting of KGeH3, NaGeH3 and MR3GeH3, wherein M is a Group IV element and R is an organic ligand. The silane triflate can be HxSi(OSO2CF3)4-x or HxSi(OSO2C4F9)4-x. The method can be used to synthesize trisilane, (H3Si)2SiH2, and the iso-tetrasilane analog, (H3Si)3SiH, by combining a silane triflate with a compound comprising a SiH3 ligand under conditions whereby the silicon hydride is formed. The silane triflate can include HxSi(OSO2CF3)4-x or HxSi(OSO2C4F9)4-x wherein x=1 or 2. A method for synthesizing (H3Ge)2SiH2 includes combining H3GeSiH2(OSO2CF3) with KGeH3 under conditions whereby (H3Ge)2SiH2 is formed.
    Type: Grant
    Filed: July 12, 2011
    Date of Patent: October 29, 2013
    Assignee: Arizona Board of Regents, a body corporate of the State of Arizona acting for and on behalf of Arizona State University
    Inventors: John Kouvetakis, Cole J. Ritter, John Tolle
  • Patent number: 8545627
    Abstract: Semiconductor structures are provided comprising a substrate and a epitaxial layer formed over the substrate, wherein the epitaxial layer comprises B; and one or more element selected from the group consisting of Zr, Hf and Al and has a thickness greater than 50 nm. Further, methods for integrating Group III nitrides onto a substrate comprising, forming an epitaxial buffer layer of a diboride of Zr, Hf, Al, or mixtures thereof, over a substrate; and forming a Group III nitride layer over the buffer layer, are provided which serve to thermally decouple the buffer layer from the underlying substrate, thereby greatly reducing the strain induced in the semiconductor structures upon fabrication and/or operation.
    Type: Grant
    Filed: April 12, 2011
    Date of Patent: October 1, 2013
    Assignee: Arizona Board of Regents
    Inventors: John Kouvetakis, Radek Roucka
  • Patent number: 8524582
    Abstract: The present invention provides novel silicon-germanium hydride compounds, methods for their synthesis, methods for their deposition, and semiconductor structures made using the novel compounds.
    Type: Grant
    Filed: February 28, 2012
    Date of Patent: September 3, 2013
    Assignee: The Arizona Board of Regents
    Inventors: John Kouvetakis, Cole J. Ritter, III
  • Patent number: 8518360
    Abstract: The present invention provides novel silicon-germanium hydride compounds, methods for their synthesis, methods for their deposition, and semiconductor structures made using the novel compounds.
    Type: Grant
    Filed: July 6, 2012
    Date of Patent: August 27, 2013
    Inventors: John Kouvetakis, Cole J. Ritter, III, Changwu Hu, Ignatius S. T. Tsong, Andrew Chizmeshya
  • Publication number: 20130032857
    Abstract: The present invention provides novel silicon-germanium hydride compounds, methods for their synthesis, methods for their deposition, and semiconductor structures made using the novel compounds.
    Type: Application
    Filed: July 6, 2012
    Publication date: February 7, 2013
    Applicant: The Arizona Board of Regents, a body corporate acting on behalf of Arizona State University
    Inventors: John Kouvetakis, Cole J. Ritter, III, Changwu Hu, Ignatius S.T. Tsong, Andrew Chizmeshya
  • Publication number: 20120217618
    Abstract: The present invention provides novel silicon-germanium hydride compounds, methods for their synthesis, methods for their deposition, and semiconductor structures made using the novel compounds.
    Type: Application
    Filed: February 28, 2012
    Publication date: August 30, 2012
    Applicant: The Arizona Board of Regents, a body corporated acting on behalf of Arizona State University
    Inventors: John Kouvetakis, Cole J. Ritter, III
  • Patent number: 8216537
    Abstract: The present invention provides novel silicon-germanium hydride compounds, methods for their synthesis, methods for their deposition, and semiconductor structures made using the novel compounds.
    Type: Grant
    Filed: November 21, 2006
    Date of Patent: July 10, 2012
    Assignee: Arizona Board of Regents
    Inventors: John Kouvetakis, Cole J. Ritter, III, Changwu Hu, Ignatius S. T. Tsong, Andrew Chizmeshya
  • Patent number: 8133802
    Abstract: The present invention provides silicon-germanium hydride compounds, methods for their synthesis, methods for their deposition, and semiconductor structures made using the compounds. The compounds are defined by formula: SiHnI (GeHn2)y, wherein y is 2, 3, or 4 wherein n1 is 0 1, 2 or 3 to satisfy valency and wherein n2 is independently 0, 1, 2 or 3 for each Ge atom in the compound, to satisfy valency.
    Type: Grant
    Filed: November 21, 2006
    Date of Patent: March 13, 2012
    Assignee: Arizona Board of Regents
    Inventors: John Kouvetakis, Cole J. Ritter, III
  • Publication number: 20120025212
    Abstract: Photodiode devices with GeSn active layers can be integrated directly on p+ Si platforms under CMOS-compatible conditions. It has been found that even minor amounts of Sn incorporation (2%) dramatically expand the range of IR detection up to at least 1750 nm and substantially increases the absorption. The corresponding photoresponse can cover of all telecommunication bands using entirely group IV materials.
    Type: Application
    Filed: September 16, 2009
    Publication date: February 2, 2012
    Applicant: Arizona Board of Regents, a body corporate acting for and on behalf of Arizona State University
    Inventors: John Kouvetakis, Jose Menendez, Radek Roucka, Jay Mathews
  • Publication number: 20120020864
    Abstract: A method is provided for synthesizing silicon-germanium hydride compounds of the formula (H3Ge)4-xSiHx, wherein x=0, 1, 2 or 3. The method includes combining a silane triflate with a compound having a GeH3 ligand under conditions whereby the silicon-germanium hydride is formed. The compound having the GeH3 ligand is selected from the group consisting of KGeH3, NaGeH3 and MR3GeH3, wherein M is a Group IV element and R is an organic ligand. The silane triflate can be HxSi(OSO2CF3)4-x or HxSi(OSO2C4F9)4-x. The method can be used to synthesize trisilane, (H3Si)2SiH2, and the iso-tetrasilane analog, (H3Si)3SiH, by combining a silane triflate with a compound comprising a SiH3 ligand under conditions whereby the silicon hydride is formed. The silane triflate can include HxSi(OSO2CF3)4-x or HxSi(OSO2C4F9)4-x wherein x=1 or 2. A method for synthesizing (H3Ge)2SiH2 includes combining H3GeSiH2(OSO2CF3) with KGeH3 under conditions whereby (H3Ge)2SiH2 is formed.
    Type: Application
    Filed: July 12, 2011
    Publication date: January 26, 2012
    Applicants: Arizona State
    Inventors: John Kouvetakis, Cole J. Ritter, III, John Tolle
  • Publication number: 20110316043
    Abstract: Thin group IV semiconductor structures are provided comprising a thin Si substrate and a second region formed directly on the Si substrate, where the second region comprises either (i) a Ge1-xSnx layer; or (ii) a Ge layer having a threading dislocation density of less than about 105/cm2, and the effective bandgap of the second region is less than the effective bandgap of the Si substrate. Further, methods for preparing the thin group IV semiconductor structures are provided. Such structures are useful, for example, as components of solar cells.
    Type: Application
    Filed: September 16, 2009
    Publication date: December 29, 2011
    Applicant: Arizona Board of Regents
    Inventors: John Kouvetakis, Jose Menendez
  • Patent number: 8043980
    Abstract: The invention provides compounds of, and methods for the preparation of compounds of, the molecular formula, SixGeyHz—aXa; wherein X is halogen, and x, y, z, and a are defined herein, and methods for the deposition of high-Ge content Si films on silicon substrates using compounds of the invention.
    Type: Grant
    Filed: April 2, 2008
    Date of Patent: October 25, 2011
    Assignee: Arizona Board of Regents, A Body Corporate Acting for and on Behalf of Arizona State University
    Inventors: John Kouvetakis, Jesse Tice, Yan-Yan Fang
  • Publication number: 20110254052
    Abstract: Described herein are semiconductor structures comprising (i) a Si substrate; (ii) a buffer region formed directly over the Si substrate, wherein the buffer region comprises (a) a Ge layer having a threading dislocation density below about 105 cm?2; or (b) a Ge1-xSnx layer formed directly over the Si substrate and a Ge1-x-ySixSny layer formed over the Ge1-xSnx layer; and (iii) a plurality of III-V active blocks formed over the buffer region, wherein the first III-V active block formed over the buffer region is lattice matched or pseudomorphically strained to the buffer region. Further, methods for forming the semiconductor structures are provided and novel Ge1-x-ySixSny, alloys are provided that are lattice matched or pseudomorphically strained to Ge and have tunable band gaps ranging from about 0.80 eV to about 1.4O eV.
    Type: Application
    Filed: September 16, 2009
    Publication date: October 20, 2011
    Applicant: Arizona Board of Regents, a body corporate acting for and on behalf of Arizona State University
    Inventors: John Kouvetakis, Jose Menendez
  • Patent number: 8029905
    Abstract: The present invention provides novel compounds of the formula Gei-x-ySixSny, wherein 0.01<y<0.11, and 0.26<x<0.35, and semiconductor structures comprising such compounds. The present invention also provides novel semiconductor structures comprising silicon substrates, an SiGe buffer layer, and a Group III-V or II-VI active layer. The present invention also provides novel semiconductor structures comprising silicon substrates, an SiGe buffer layer, an SiGeSn template layer, and an SiGe, Ge, Group III-V, or Group II-VI active layer.
    Type: Grant
    Filed: March 10, 2006
    Date of Patent: October 4, 2011
    Assignee: Arizona Board of Regents, a Body Corporate of the State of Arizona acting for and on behalf of Arizona State University
    Inventors: John Kouvetakis, Radek Roucka
  • Publication number: 20110198729
    Abstract: The present disclosure describes methods for preparing semiconductor structures, comprising forming a Ge1-ySny buffer layer on a semiconductor substrate and forming a tensile strained Ge layer on the Ge1-ySny buffer layer using an admixture of (GeH3)2CH2 and Ge2H6 in a ratio of between 1:10 and 1:30. The disclosure further provides semiconductor structures having highly strained Ge epilayers (e.g., between about 0.15% and 0.45%) as well as compositions comprising an admixture of (GeH3)2CH2 and Ge2H6 in a ratio of between about 1:10 and 1:30. The methods herein provide, and the semiconductor structure provide, Ge epilayers having high strain levels which can be useful in semiconductor devices for example, in optical fiber communications devices.
    Type: Application
    Filed: February 23, 2011
    Publication date: August 18, 2011
    Applicants: of Arizona State University
    Inventors: John Kouvetakis, Yan-Yan Fang
  • Publication number: 20110189838
    Abstract: Semiconductor structures are provided comprising a substrate and a epitaxial layer formed over the substrate, wherein the epitaxial layer comprises B; and one or more element selected from the group consisting of Zr, Hf and Al and has a thickness greater than 50 nm. Further, methods for integrating Group III nitrides onto a substrate comprising, forming an epitaxial buffer layer of a diboride of Zr, Hf, Al, or mixtures thereof, over a substrate; and forming a Group III nitride layer over the buffer layer, are provided which serve to thermally decouple the buffer layer from the underlying substrate, thereby greatly reducing the strain induced in the semiconductor structures upon fabrication and/or operation.
    Type: Application
    Filed: April 12, 2011
    Publication date: August 4, 2011
    Applicant: Arizona Board of Regents, a body corporate of the State of Arizona, acting for and on behalf of Ariz
    Inventors: John Kouvetakis, Radek Roucka
  • Patent number: 7981392
    Abstract: A method is provided for synthesizing silicon-germanium hydride compounds of the formula (H3Ge)4-XSiHX, wherein x=0, 1, 2 or 3. The method includes combining a silane triflate with a compound having a GeH3 ligand under conditions whereby the silicon-germanium hydride is formed. The compound having the GeH3 ligand is selected from the group consisting of KGeH3, NaGeH3 and MR3GeH3, wherein M is a Group IV element and R is an organic ligand. The silane triflate can be HXSi(OSO2CF3)4-x or HxSi(OSO2C4F9)4-x. The method can be used to synthesize trisilane, (H3Si)2SiH2, and the iso-tetrasilane analog, (H3Si)3SiH, by combining a silane triflate with a compound comprising a SiH3 ligand under conditions whereby the silicon hydride is formed. The silane triflate can include HXSi(OSO2CF3)4-x or HXSi(OSO2C4F9)4-x wherein x=1 or 2. A method for synthesizing (H3Ge)2SiH2 includes combining H3GeSiH2(OSO2CF3) with KGeH3 under conditions whereby (H3Ge)2SiH2 is formed.
    Type: Grant
    Filed: December 31, 2004
    Date of Patent: July 19, 2011
    Assignee: The Arizona Board of Regents, a body corporate of the state of Arizona acting for and on behalf of Arizona State University
    Inventors: John Kouvetakis, Cole J. Ritter, III, John Tolle