Patents by Inventor Rahul Sen

Rahul Sen 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: 8128993
    Abstract: Methods for forming anisotropic nanotube fabrics are disclosed. In one aspect, a nanotube application solution is rendered into a nematic state prior to its application over a substrate. In another aspect, a pump and narrow nozzle assembly are employed to realize a flow induced alignment of a plurality of individual nanotube elements as they are deposited onto a substrate element. In another aspect, nanotube adhesion promoter materials are used to form a patterned nanotube application layer, providing narrow channels over which nanotube elements will self align during an application process. Specific dip coating processes which are well suited for aiding in the creation of anisotropic nanotube fabrics are also disclosed.
    Type: Grant
    Filed: July 31, 2009
    Date of Patent: March 6, 2012
    Assignee: Nantero Inc.
    Inventors: Thomas Rueckes, Ramesh Sivarajan, Rahul Sen
  • Patent number: 8110883
    Abstract: Electromagnetic radiation detecting and sensing systems using carbon nanotube fabrics and methods of making the same are provided. In certain embodiments of the invention, an electromagnetic radiation detector includes a substrate, a nanotube fabric disposed on the substrate, the nanotube fabric comprising a non-woven network of nanotubes, and first and second conductive terminals, each in electrical communication with the nanotube fabric, the first and second conductive terminals disposed in space relation to one another. Nanotube fabrics may be tuned to be sensitive to a predetermined range of electromagnetic radiation such that exposure to the electromagnetic radiation induces a change in impedance between the first and second conductive terminals. The detectors include microbolometers, themistors and resistive thermal sensors, each constructed with nanotube fabric. Nanotube fabric detector arrays may be formed for broad-range electromagnetic radiation detecting.
    Type: Grant
    Filed: March 12, 2008
    Date of Patent: February 7, 2012
    Assignee: Nantero Inc.
    Inventors: Jonathan W. Ward, Elwood James Egerton, Rahul Sen, Brent M. Segal
  • Publication number: 20110291315
    Abstract: A method for arranging nanotube elements within nanotube fabric layers and films is disclosed. A directional force is applied over a nanotube fabric layer to render the fabric layer into an ordered network of nanotube elements. That is, a network of nanotube elements drawn together along their sidewalls and substantially oriented in a uniform direction. In some embodiments this directional force is applied by rolling a cylindrical element over the fabric layer. In other embodiments this directional force is applied by passing a rubbing material over the surface of a nanotube fabric layer. In other embodiments this directional force is applied by running a polishing material over the nanotube fabric layer for a predetermined time. Exemplary rolling, rubbing, and polishing apparatuses are also disclosed.
    Type: Application
    Filed: March 30, 2011
    Publication date: December 1, 2011
    Applicant: Nantero, Inc.
    Inventors: David A. ROBERTS, Hao-Yu LIN, Thomas R. BENGTSON, Thomas RUECKES, Karl ROBINSON, H. Montgomery MANNING, Rahul SEN, Michel MONTEIRO
  • Publication number: 20110244121
    Abstract: A method for arranging nanotube elements within nanotube fabric layers and films is disclosed. A directional force is applied over a nanotube fabric layer to render the fabric layer into an ordered network of nanotube elements. That is, a network of nanotube elements drawn together along their sidewalls and substantially oriented in a uniform direction. In some embodiments this directional force is applied by rolling a cylindrical element over the fabric layer. In other embodiments this directional force is applied by passing a rubbing material over the surface of a nanotube fabric layer. In other embodiments this directional force is applied by running a polishing material over the nanotube fabric layer for a predetermined time. Exemplary rolling, rubbing, and polishing apparatuses are also disclosed.
    Type: Application
    Filed: November 12, 2010
    Publication date: October 6, 2011
    Applicant: Nantero, Inc.
    Inventors: David A. Roberts, Hao-Yu Lin, Thomas R. Bengtson, Thomas Rueckes, Karl Robinson, H. Montgomery Manning, Rahul Sen, Michel Pires Monteiro
  • Publication number: 20110203632
    Abstract: Photovoltaic (PV) devices employing layers of semiconducting carbon nanotubes as light absorption elements are disclosed. In one aspect a layer of p-type carbon nanotubes and a layer of n-type carbon nanotubes are used to form a p-n junction PV device. In another aspect a mixed layer of p-type and n-type carbon nanotubes are used to form a bulk hetero-junction PV device. In another aspect a metal such as a low work function metal electrode is formed adjacent to a layer of semiconducting nanotubes to form a Schottky barrier PV device. In another aspect various material deposition techniques well suited to working with nanotube layers are employed to realize a practical metal-insulator-semiconductor (MIS) PV device. In another aspect layers of metallic nanotubes are used to provide flexible electrode elements for PV devices. In another aspect layers of metallic nanotubes are used to provide transparent electrode elements for PV devices.
    Type: Application
    Filed: February 22, 2010
    Publication date: August 25, 2011
    Inventors: RAHUL SEN, SUCHIT SHAH, HAO-YU LIN, THOMAS RUECKES
  • Publication number: 20110163290
    Abstract: Methods for passivating a carbonic nanolayer (that is, material layers comprised of low dimensional carbon structures with delocalized electrons such as carbon nanotubes and nano-scopic graphene flecks) to prevent or otherwise limit the encroachment of another material layer are disclosed. In some embodiments, a sacrificial material is implanted within a porous carbonic nanolayer to fill in the voids within the porous carbonic nanolayer while one or more other material layers are applied over or alongside the carbonic nanolayer. Once the other material layers are in place, the sacrificial material is removed. In other embodiments, a non-sacrificial filler material (selected and deposited in such a way as to not impair the switching function of the carbonic nanolayer) is used to form a barrier layer within a carbonic nanolayer. In other embodiments, carbon structures are combined with and nanoscopic particles to limit the porosity of a carbonic nanolayer.
    Type: Application
    Filed: October 22, 2010
    Publication date: July 7, 2011
    Applicant: Nantero, Inc.
    Inventors: Thomas Rueckes, H. Montgomery Manning, Rahul Sen
  • Publication number: 20110027491
    Abstract: Methods for forming anisotropic nanotube fabrics are disclosed. In one aspect, a nanotube application solution is rendered into a nematic state prior to its application over a substrate. In another aspect, a pump and narrow nozzle assembly are employed to realize a flow induced alignment of a plurality of individual nanotube elements as they are deposited onto a substrate element. In another aspect, nanotube adhesion promoter materials are used to form a patterned nanotube application layer, providing narrow channels over which nanotube elements will self align during an application process. Specific dip coating processes which are well suited for aiding in the creation of anisotropic nanotube fabrics are also disclosed.
    Type: Application
    Filed: July 31, 2009
    Publication date: February 3, 2011
    Applicant: Nantero, Inc.
    Inventors: Thomas RUECKES, Ramesh SIVARAJAN, Rahul SEN
  • Publication number: 20110027497
    Abstract: Methods for forming anisotropic nanotube fabrics are disclosed. In one aspect, a nanotube application solution is rendered into a nematic state prior to its application over a substrate. In another aspect, a pump and narrow nozzle assembly are employed to realize a flow induced alignment of a plurality of individual nanotube elements as they are deposited onto a substrate element. In another aspect, nanotube adhesion promoter materials are used to form a patterned nanotube application layer, providing narrow channels over which nanotube elements will self align during an application process. Specific dip coating processes which are well suited for aiding in the creation of anisotropic nanotube fabrics are also disclosed.
    Type: Application
    Filed: July 31, 2009
    Publication date: February 3, 2011
    Applicant: Nantero, Inc.
    Inventors: Thomas RUECKES, Ramesh SIVARAJAN, Rahul SEN
  • Patent number: 7858185
    Abstract: Certain spin-coatable liquids and application techniques are described, which can be used to form nanotube films or fabrics of controlled properties. A spin-coatable liquid for formation of a nanotube film includes a liquid medium containing a controlled concentration of purified nanotubes, wherein the controlled concentration is sufficient to form a nanotube fabric or film of preselected density and uniformity, and wherein the spin-coatable liquid comprises less than 1×1018 atoms/cm3 of metal impurities. The spin-coatable liquid is substantially free of particle impurities having a diameter of greater than about 500 nm.
    Type: Grant
    Filed: June 3, 2004
    Date of Patent: December 28, 2010
    Assignee: Nantero, Inc.
    Inventors: Rahul Sen, Ramesh Sivarajan, Thomas Rueckes, Brent M. Segal
  • Publication number: 20100147657
    Abstract: Device design methods for use with non-volatile nanotube switches are disclosed. In a first aspect of the present disclosure, a plurality of nonconductive nanoparticles is adhered to a nanotube element such as to provide an isolation barrier from a control electrode and further provide a switching gap above that element. In a second aspect of the present disclosure, conductive nanoparticles are dispersed and adhered to either a control electrode or to a nanotube element positioned over said electrode element such that the interface area (that is, the area of the nanotube element which comes into contact with the control electrode) is minimized. In a third aspect of the present disclosure, a monolayer network of nonconductive nanotubes is used to provide an isolation barrier between a control electrode and a nanotube element. Voids or spaces in said monolayer network further provides switching gaps.
    Type: Application
    Filed: August 7, 2009
    Publication date: June 17, 2010
    Applicant: Nantero, Inc.
    Inventors: Rahul Sen, Ramesh Sivarajan, Thomas Rueckes, Jonathan W. Ward
  • Publication number: 20100051880
    Abstract: Certain applicator liquids and method of making the applicator liquids are described. The applicator liquids can be used to form nanotube films or fabrics of controlled properties. An applicator liquid for preparation of a nanotube film or fabric includes a controlled concentration of nanotubes dispersed in a liquid medium containing water. The controlled concentration is sufficient to form a nanotube fabric or film of preselected density and uniformity.
    Type: Application
    Filed: November 4, 2009
    Publication date: March 4, 2010
    Inventors: Eliodor G. Ghenciu, Tzong-Ru T. Han, Ramesh SIVARAJAN, Thomas Rueckes, Rahul Sen, Brent M. Segal, Jonathan W. Ward
  • Patent number: 7666382
    Abstract: Certain applicator liquids and method of making the applicator liquids are described. The applicator liquids can be used to form nanotube films or fabrics of controlled properties. An applicator liquid for preparation of a nanotube film or fabric includes a controlled concentration of nanotubes dispersed in a liquid medium containing water. The controlled concentration is sufficient to form a nanotube fabric or film of preselected density and uniformity.
    Type: Grant
    Filed: December 15, 2005
    Date of Patent: February 23, 2010
    Assignee: Nantero, Inc.
    Inventors: Eliodor G. Ghenciu, Tzong-Ru Terry Han, Ramesh Sivarajan, Thomas Rueckes, Rahul Sen, Brent M. Segal, Jonathan W. Ward
  • Patent number: 7658869
    Abstract: Certain applicator liquids and application techniques are described, which can be used to form nanotube films or fabrics of controlled properties. An applicator liquid for preparation of a nanotube film or fabric includes a controlled concentration of nanotubes dispersed in ethyl lactate. The controlled concentration is sufficient to form a nanotube fabric or film of preselected density and uniformity.
    Type: Grant
    Filed: June 3, 2004
    Date of Patent: February 9, 2010
    Assignee: Nantero, Inc.
    Inventors: Rahul Sen, Ramesh Sivarajan, Thomas Rueckes, Brent M. Segal
  • Patent number: 7556746
    Abstract: Certain spin-coatable liquids and application techniques are described, which can be used to form nanotube films or fabrics of controlled properties. A method of making an applicator liquid containing nanotubes for use in an electronics fabrication process includes characterizing an electronic fabrication process according to fabrication compatible solvents and allowable levels of metallic and particle impurities; providing nanotubes that satisfy the allowable impurities criteria for the electronics fabrication process; providing a solvent that meets the fabrication compatible solvents and allowable impurities criteria for the electronic fabrication process; and dispersing the nanotubes into the solvent at a concentration of at least one milligram of nanotubes per liter solvent to form an applicator liquid.
    Type: Grant
    Filed: June 3, 2004
    Date of Patent: July 7, 2009
    Assignee: Nantero, Inc.
    Inventors: Rahul Sen, Ramesh Sivarajan, Thomas Rueckes, Brent M. Segal
  • Publication number: 20090140213
    Abstract: Certain spin-coatable liquids and application techniques are described, which can be used to form nanotube films or fabrics of controlled properties. A method of making an applicator liquid containing nanotubes for use in an electronics fabrication process includes characterizing an electronic fabrication process according to fabrication compatible solvents and allowable levels of metallic and particle impurities; providing nanotubes that satisfy the allowable impurities criteria for the electronics fabrication process; providing a solvent that meets the fabrication compatible solvents and allowable impurities criteria for the electronic fabrication process; and dispersing the nanotubes into the solvent at a concentration of at least one milligram of nanotubes per liter solvent to form an applicator liquid.
    Type: Application
    Filed: June 3, 2004
    Publication date: June 4, 2009
    Applicant: Nantero, Inc.
    Inventors: Rahul Sen, Ramesh Sivarajan, Thomas Rueckes, Brent M. Segal
  • Patent number: 7504051
    Abstract: Certain spin-coatable liquids and application techniques are described, which can be used to form nanotube films or fabrics of controlled properties. A spin-coatable liquid containing nanotubes for use in an electronics fabrication process includes a solvent containing a plurality of nanotubes. The nanotubes are at a concentration of greater than 1 mg/L. The nanotubes are pretreated to reduce the level of metallic and particulate impurities to a preselected level, and the preselected metal and particulate impurities levels are selected to be compatible with an electronics manufacturing process. The solvent also is selected for compatibility with an electronics manufacturing process.
    Type: Grant
    Filed: June 3, 2004
    Date of Patent: March 17, 2009
    Assignee: Nantero, Inc.
    Inventors: Rahul Sen, Ramesh Sivarajan, Thomas Rueckes, Brent M. Segal
  • Publication number: 20080251723
    Abstract: Electromagnetic radiation detecting and sensing systems using carbon nanotube fabrics and methods of making the same are provided. In certain embodiments of the invention, an electromagnetic radiation detector includes a substrate, a nanotube fabric disposed on the substrate, the nanotube fabric comprising a non-woven network of nanotubes, and first and second conductive terminals, each in electrical communication with the nanotube fabric, the first and second conductive terminals disposed in space relation to one another. Nanotube fabrics may be tuned to be sensitive to a predetermined range of electromagnetic radiation such that exposure to the electromagnetic radiation induces a change in impedance between the first and second conductive terminals. The detectors include microbolometers, themistors and resistive thermal sensors, each constructed with nanotube fabric. Nanotube fabric detector arrays may be formed for broad-range electromagnetic radiation detecting.
    Type: Application
    Filed: March 12, 2008
    Publication date: October 16, 2008
    Inventors: Jonathan W. Ward, Elwood James Egerton, Rahul Sen, Brent M. Segal
  • Publication number: 20080224126
    Abstract: Certain spin-coatable liquids and application techniques are described, which can be used to form nanotube films or fabrics of controlled properties. A spin-coatable liquid for formation of a nanotube film includes a liquid medium containing a controlled concentration of purified nanotubes, wherein the controlled concentration is sufficient to form a nanotube fabric or film of preselected density and uniformity, and wherein the spin-coatable liquid comprises less than 1×1018 atoms/cm3 of metal impurities. The spin-coatable liquid is substantially free of particle impurities having a diameter of greater than about 500 nm.
    Type: Application
    Filed: July 25, 2007
    Publication date: September 18, 2008
    Applicant: Nantero, Inc.
    Inventors: Rahul Sen, Ramesh Sivarajan, Thomas Rueckes, Brent M. Segal
  • Publication number: 20080179571
    Abstract: Certain spin-coatable liquids and application techniques are described, which can be used to form nanotube films or fabrics of controlled properties. A spin-coatable liquid for formation of a nanotube film includes a liquid medium containing a controlled concentration of purified nanotubes, wherein the controlled concentration is sufficient to form a nanotube fabric or film of preselected density and uniformity, and wherein the spin-coatable liquid comprises less than 1×1018 atoms/cm3 of metal impurities. The spin-coatable liquid is substantially free of particle impurities having a diameter of greater than about 500 nm.
    Type: Application
    Filed: July 25, 2007
    Publication date: July 31, 2008
    Applicant: Nantero, Inc.
    Inventors: Rahul Sen, Ramesh Sivarajan, Thomas Rueckes, Brent M. Segal
  • Patent number: 7375369
    Abstract: Certain spin-coatable liquids and application techniques are described, which can be used to form nanotube films or fabrics of controlled properties. A spin-coatable liquid for formation of a nanotube film includes a liquid medium containing a controlled concentration of purified nanotubes, wherein the controlled concentration is sufficient to form a nanotube fabric or film of preselected density and uniformity, and wherein the spin-coatable liquid includes less than 1×1018 atoms/cm3 of metal impurities. The spin-coatable liquid is substantially free of particle impurities having a diameter of greater than about 500 nm.
    Type: Grant
    Filed: June 3, 2004
    Date of Patent: May 20, 2008
    Assignee: Nantero, Inc.
    Inventors: Rahul Sen, Ramesh Sivarajan, Thomas Rueckes, Brent M. Segal