Patents by Inventor Raphael Tsu

Raphael Tsu 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: 10374037
    Abstract: A semiconductor junction may include a first semiconductor material and a second material. The first and the second semiconductor materials are extrinsically undoped. At least a portion of a valence band of the second material has a higher energy level than at least a portion of the conduction band of the first semiconductor material (type-III band alignment). A flow of a majority of free carriers across the semiconductor junction is diffusive. A region of generation and/or recombination of a plurality of free carriers is confined to a two-dimensional surface of the second material, and at the interface of the first semiconductor material and the second material.
    Type: Grant
    Filed: February 27, 2014
    Date of Patent: August 6, 2019
    Assignee: THE UNIVERSITY OF NORTH CAROLINA AT CHARLOTTE
    Inventors: Raphael Tsu, Ian T. Ferguson, Nikolaus Dietz
  • Patent number: 10203526
    Abstract: A semiconductor junction may include a first layer and a second layer. The first layer may include a first semiconductor material and the second layer may be deposited on the first layer and may include a second material. The valence band maximum of the second material is higher than a conduction band minimum of the first semiconductor material, thereby allowing a flow of a majority of free carriers across the semiconductor junction between the first and second layers to be diffusive.
    Type: Grant
    Filed: July 6, 2016
    Date of Patent: February 12, 2019
    Assignee: THE UNIVERSITY OF NORTH CAROLINA AT CHARLOTTE
    Inventors: Raphael Tsu, Michael Fiddy, Tsinghua Her
  • Patent number: 9812527
    Abstract: Graphene is used as an interfacial layer to grow Si and other semiconductors or crystalline materials including two-dimensional Si and other structures on any foreign substrate that can withstand the growth temperature without the limitation matching condition typically required for epitaxial growth.
    Type: Grant
    Filed: March 20, 2017
    Date of Patent: November 7, 2017
    Assignee: THE UNIVERSITY OF NORTH CAROLINA AT CHARLOTTE
    Inventors: Yong Zhang, Raphael Tsu, Naili Yue
  • Publication number: 20170194437
    Abstract: Graphene is used as an interfacial layer to grow Si and other semiconductors or crystalline materials including two-dimensional Si and other structures on any foreign substrate that can withstand the growth temperature without the limitation matching condition typically required for epitaxial growth.
    Type: Application
    Filed: March 20, 2017
    Publication date: July 6, 2017
    Applicant: THE UNIVERSITY OF NORTH CAROLINA AT CHARLOTTE
    Inventors: Yong ZHANG, Raphael TSU, Naili YUE
  • Patent number: 9601579
    Abstract: Graphene is used as an interfacial layer to grow Si and other semiconductors or crystalline materials including two-dimensional Si and other structures on any foreign substrate that can withstand the growth temperature without the limitation matching condition typically required for epitaxial growth.
    Type: Grant
    Filed: May 27, 2014
    Date of Patent: March 21, 2017
    Assignee: THE UNIVERSITY OF NORTH CAROLINA AT CHARLOTTE
    Inventors: Yong Zhang, Raphael Tsu, Naili Yue
  • Publication number: 20170010484
    Abstract: A semiconductor junction may include a first layer and a second layer. The first layer may include a first semiconductor material and the second layer may be deposited on the first layer and may include a second material. The valence band maximum of the second material is higher than a conduction band minimum of the first semiconductor material, thereby allowing a flow of a majority of free carriers across the semiconductor junction between the first and second layers to be diffusive.
    Type: Application
    Filed: July 6, 2016
    Publication date: January 12, 2017
    Applicant: THE UNIVERSITY OF NORTH CAROLINA AT CHARLOTTE
    Inventors: Raphael TSU, Michael FIDDY, Tsinghua HER
  • Publication number: 20160064489
    Abstract: Graphene is used as an interfacial layer to grow Si and other semiconductors or crystalline materials including two-dimensional Si and other structures on any foreign substrate that can withstand the growth temperature without the limitation matching condition typically required for epitaxial growth.
    Type: Application
    Filed: May 27, 2014
    Publication date: March 3, 2016
    Applicant: THE UNIVERSITY OF NORTH CAROLINA AT CHARLOTTE
    Inventors: Yong ZHANG, Raphael TSU, Naili YUE
  • Publication number: 20150340439
    Abstract: A semiconductor junction may include a first semiconductor material and a second material. The first and the second semiconductor materials are extrinsically undoped. At least a portion of a valence band of the second material has a higher energy level than at least a portion of the conduction band of the first semiconductor material (type-III band alignment). A flow of a majority of free carriers across the semiconductor junction is diffusive. A region of generation and/or recombination of a plurality of free carriers is confined to a two-dimensional surface of the second material, and at the interface of the first semiconductor material and the second material.
    Type: Application
    Filed: February 27, 2014
    Publication date: November 26, 2015
    Applicants: GEORGIA STATE UNIVERSITY RESEARCH FOUNDATION, INC., THE UNIVERSITY OF NORTH CAROLINA AT CHARLOTTE
    Inventors: Raphael TSU, Ian T. FERGUSON, Nikolaus DIETZ
  • Patent number: 9000432
    Abstract: A multilayered structure is provided. The multilayered structure may include a silicon substrate and a film of gadolinium oxide disposed on the silicon substrate. The top surface of the silicon substrate may have silicon orientated in the 100 direction (Si(100)) and the gadolinium oxide disposed thereon may have an orientation in the 100 direction (Gd2O3(100)).
    Type: Grant
    Filed: June 25, 2014
    Date of Patent: April 7, 2015
    Assignee: The University of North Carolina at Charlotte
    Inventors: Raphael Tsu, Wattaka Sitapura, John Hudak
  • Publication number: 20140306315
    Abstract: A multilayered structure is provided. The multilayered structure may include a silicon substrate and a film of gadolinium oxide disposed on the silicon substrate. The top surface of the silicon substrate may have silicon orientated in the 100 direction (Si(100)) and the gadolinium oxide disposed thereon may have an orientation in the 100 direction (Gd2O3(100)).
    Type: Application
    Filed: June 25, 2014
    Publication date: October 16, 2014
    Applicant: THE UNIVERSITY OF NORTH CAROLINA AT CHARLOTTE
    Inventors: Raphael TSU, Wattaka SITAPURA, John HUDAK
  • Patent number: 8846506
    Abstract: A multilayered structure is provided. The multilayered structure may include a silicon substrate and a film of gadolinium oxide disposed on the silicon substrate. The top surface of the silicon substrate may have silicon orientated in the 100 direction (Si(100)) and the gadolinium oxide disposed thereon may have an orientation in the 100 direction (Gd2O3(100)).
    Type: Grant
    Filed: April 22, 2013
    Date of Patent: September 30, 2014
    Assignee: The University of North Carolina at Charlotte
    Inventors: Raphael Tsu, Wattaka Sitapura, John Hudak
  • Publication number: 20130285048
    Abstract: A multilayered structure is provided. The multilayered structure may include a silicon substrate and a film of gadolinium oxide disposed on the silicon substrate. The top surface of the silicon substrate may have silicon orientated in the 100 direction (Si(100)) and the gadolinium oxide disposed thereon may have an orientation in the 100 direction (Gd2O3(100)).
    Type: Application
    Filed: April 22, 2013
    Publication date: October 31, 2013
    Applicant: THE UNIVERSITY OF NORTH CAROLINA AT CHARLOTTE
    Inventors: Raphael TSU, Wattaka SITAPURA, John HUDAK
  • Patent number: 7105895
    Abstract: A method for producing an insulating or barrier layer (FIG. 1B), useful for semiconductor devices, comprises depositing a layer of silicon and at least one additional element on a silicon substrate whereby said deposited layer is substantially free of defects such that epitaxial silicon substantially free of defects can be deposited on said deposited layer. Alternatively, a monolayer of one or more elements, preferably comprising oxygen, is absorbed on a silicon substrate. A plurality of insulating layers sandwiched between epitaxial silicon forms a barrier composite. Semiconductor devices are disclosed which comprise said barrier composite.
    Type: Grant
    Filed: June 14, 2001
    Date of Patent: September 12, 2006
    Assignee: Nanodynamics, Inc.
    Inventors: Chia-Gee Wang, Raphael Tsu, John Clay Lofgren
  • Patent number: 7023010
    Abstract: A Si/C superlattice useful for semiconductor devices comprises a plurality of epitaxially grown silicon layers alternating with carbon layers respectively adsorbed on surfaces of said silicon layers. Structures and devices comprising the superlattice and methods are described.
    Type: Grant
    Filed: April 14, 2004
    Date of Patent: April 4, 2006
    Assignee: Nanodynamics, Inc.
    Inventors: Chia Gee Wang, Raphael Tsu
  • Publication number: 20060003500
    Abstract: A method for producing an insulating or barrier layer (FIG. 1B), useful for semiconductor devices, comprises depositing a layer of silicon and at least one additional element on a silicon substrate whereby said deposited layer is substantially free of defects such that epitaxial silicon substantially free of defects can be deposited on said deposited layer. Alternatively, a monolayer of one or more elements, preferably comprising oxygen, is absorbed on a silicon substrate. A plurality of insulating layers sandwiched between epitaxial silicon forms a barrier composite. Semiconductor devices are disclosed which comprise said barrier composite.
    Type: Application
    Filed: June 14, 2001
    Publication date: January 5, 2006
    Inventors: Chia-Gee Wang, Raphael Tsu, John Lofgren
  • Publication number: 20040227165
    Abstract: A Si/C superlattice useful for semiconductor devices comprises a plurality of epitaxially grown silicon layers alternating with carbon layers respectively adsorbed on surfaces of said silicon layers. Structures and devices comprising the superlattice and methods are described.
    Type: Application
    Filed: April 14, 2004
    Publication date: November 18, 2004
    Applicant: NANODYNAMICS, INC.
    Inventors: Chia Gee Wang, Raphael Tsu
  • Patent number: 6376337
    Abstract: A method for producing an insulating or barrier layer, useful for semiconductor devices, comprises depositing a layer of silicon and at least one additional element on said silicon substrate whereby said deposited layer is substantially free of defects such that epitaxial silicon substantially free of defects can be deposited on said deposited layer. Alternatively, a monolayer of one or more elements, preferably comprising oxygen, is absorbed on a silicon substrate. A plurality of insulating layers sandwiched between epitaxial silicon forms a barrier composite. Semiconductor devices are disclosed which comprise said barrier composite.
    Type: Grant
    Filed: November 9, 1998
    Date of Patent: April 23, 2002
    Assignee: Nanodynamics, Inc.
    Inventors: Chia-Gee Wang, Raphael Tsu, John Clay Lofgren
  • Patent number: 6239450
    Abstract: A solid state electronic device exhibiting negative differential resistance is fabricated by depositing a thin layer of amorphous silicon on a single crystal substrate, doped N+. The amorphous silicon is simultaneously crystallized and oxidized in a dry N2 and O2 mixture. The result is a layer of amorphous SiO2 surrounding microclusters of crystalline silicon. A layer of polycrystalline silicon is deposited to a thickness of approximately 0.5 micron. Ohmic metal contacts are made to the top and bottom. These active layers are isolated by insulating SiO2. A bias voltage applied between the metal contacts results in negative differential resistance due to tunneling through resonant energy levels in microclusters.
    Type: Grant
    Filed: January 14, 1999
    Date of Patent: May 29, 2001
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: James F. Harvey, Robert A. Lux, Raphael Tsu
  • Patent number: 5895934
    Abstract: A solid state electronic device exhibiting negative differential resistance s fabricated by depositing a thin layer of amorphous silicon on a single crystal substrate, doped N.sup.+. The amorphous silicon is simultaneously crystallized and oxidized in a dry N.sub.2 and O.sub.2 mixture. The result is a layer of amorphous Sio.sub.2 surrounding microclusters of crystalline silicon. A layer of polycrystalline silicon is deposited to a thickness of approximately 0.5 micron. Ohmic metal contacts are made to the top and bottom. These active layers are isolated by insulating SiO.sub.2. A bias voltage applied between the metal contacts results in negative differential resistance due to tunneling through resonant energy levels in microclusters.
    Type: Grant
    Filed: August 13, 1997
    Date of Patent: April 20, 1999
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: James F. Harvey, Robert A. Lux, Raphael Tsu
  • Patent number: 5627386
    Abstract: The invention provides light sources which are easily compatible with standard silicon VLSI processing and can be located directly in the material of the silicon VLSI chip. P-type silicon substrate is processed to produce proturbances, the proturbances preferably having tip dimensions on the order of 5-10 mm. A native oxide film (SiO.sub.2) is caused to develop on the surface of the silicon substrate. A thin, transparent, conductive film is then deposited on top of the SiO.sub.2. Electrical contacts are made to the top of the conductive film and to the bottom of the silicon substrate. The carriers for electroluminescence are supplied by the P-doped silicon substrate (holes) and the conductive film (electrons). When a voltage is applied across the layers via the electrical contacts, the holes are concentrated in the region of the tip of the proturbances because the electric field lines concentrate near a pointed object, and electron current across the SiO.sub.
    Type: Grant
    Filed: October 27, 1995
    Date of Patent: May 6, 1997
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: James F. Harvey, Robert A. Lux, Raphael Tsu