Patents by Inventor Neil Dasgupta

Neil Dasgupta 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: 8168251
    Abstract: A method of making nanowire probes is provided. The method includes providing a template having a nanoporous structure, providing a probe tip that is disposed on top of the template, and growing nanowires on the probe tip, where the nanowires are grown from the probe tip along the nanopores, and the nanowires conform to the shape of the nanopores.
    Type: Grant
    Filed: October 10, 2008
    Date of Patent: May 1, 2012
    Assignees: The Board of Trustees of the Leland Stanford Junior University, Honda Motor Co., Ltd
    Inventors: Friedrich B. Prinz, Neil Dasgupta, Munekazu Motoyama
  • Publication number: 20110269298
    Abstract: A method of fabricating quantum confinements is provided. The method includes depositing, using a deposition apparatus, a material layer on a substrate, where the depositing includes irradiating the layer, before a cycle, during a cycle, and/or after a cycle of the deposition to alter nucleation of quantum confinements in the material layer to control a size and/or a shape of the quantum confinements. The quantum confinements can include quantum wells, nanowires, or quantum dots. The irradiation can be in-situ or ex-situ with respect to the deposition apparatus. The irradiation can include irradiation by photons, electrons, or ions. The deposition is can include atomic layer deposition, chemical vapor deposition, MOCVD, molecular beam epitaxy, evaporation, sputtering, or pulsed-laser deposition.
    Type: Application
    Filed: March 24, 2011
    Publication date: November 3, 2011
    Inventors: Timothy P. Holme, Andrei Iancu, Hee Joon Jung, Michael C Langston, Munekazu Motoyama, Friedrich B. Prinz, Takane Usui, Hitoshi Iwadate, Neil Dasgupta, Cheng-Chieh Chao
  • Publication number: 20100240167
    Abstract: The current invention provides a method of fabricating quantum confinement (QC) in a solar cell that includes using atomic layer deposition (ALD) for providing at least one QC structure embedded into an intrinsic region of a p-i-n diode in the solar cell, where optical and electrical properties of the confinement structure are adjusted according to at least one dimension of the confinement structure. The QC structures can include quantum wells, quantum wires, quantum tubes, and quantum dots.
    Type: Application
    Filed: March 23, 2010
    Publication date: September 23, 2010
    Inventors: Neil Dasgupta, Wonyoung Lee, Timothy P. Holme, Friedrich B. Prinz
  • Publication number: 20100089866
    Abstract: A method of making nanowire probes is provided. The method includes providing a template having a nanoporous structure, providing a probe tip that is disposed on top of the template, and growing nanowires on the probe tip, where the nanowires are grown from the probe tip along the nanopores, and the nanowires conform to the shape of the nanopores.
    Type: Application
    Filed: October 10, 2008
    Publication date: April 15, 2010
    Inventors: Friedrich B. Prinz, Neil Dasgupta, Munekazu Motoyama
  • Publication number: 20090255580
    Abstract: Efficient photovoltaic devices with quantum dots are provided. Quantum dots have numerous desirable properties that can be used in solar cells, including an easily selected bandgap and Fermi level. In particular, the size and composition of a quantum dot can determine its bandgap and Fermi level. By precise deposition of quantum dots in the active layer of a solar cell, bandgap gradients can be present for efficient sunlight absorption, exciton dissociation, and charge transport. Mismatching Fermi levels are also present between adjacent quantum dots, allowing for built-in electric fields to form and aid in charge transport and the prevention of exciton recombination.
    Type: Application
    Filed: March 24, 2009
    Publication date: October 15, 2009
    Inventors: Neil Dasgupta, Friedrich B. Prinz, Timothy P. Holme, James F. Mack
  • Publication number: 20090258157
    Abstract: Lateral nano-scale pattern control for atomic layer deposition can be provided by using a scanning tunneling microscope (SPM) tip to locally influence chemical reaction rates. An electric field and/or charge transfer can significantly reduce the potential energy barrier that affects reaction kinetics, and thereby significantly enhance reaction rates. By operating the ALD growth system in a regime where reaction rates without an electric field and/or charge transfer are negligible, deposition can be precisely controlled to occur only at locations defined by the SPM tip. Alternatively, the SPM tip can be used to locally inhibit ALD growth.
    Type: Application
    Filed: March 24, 2009
    Publication date: October 15, 2009
    Inventors: Neil Dasgupta, Friedrich B. Prinz, Timothy P. Holme, Stephen Walch, Wonyoung Lee, James F. Mack
  • Publication number: 20090238990
    Abstract: Improved tip-patterned atomic layer deposition (ALD) is provided by using a scanning probe microscope (SPM) tip to define an oxide pattern in a self-assembled monolayer deposited on a substrate. The oxide pattern can directly define the ALD deposition pattern. Alternatively, the oxide pattern can be removed (e.g., with a chemical etch), and the resulting exposed substrate pattern can be used to define the ALD deposition pattern.
    Type: Application
    Filed: March 24, 2009
    Publication date: September 24, 2009
    Inventors: Neil Dasgupta, Young Beom Kim, Wonyoung Lee, Friedrich R. Prinz
  • Publication number: 20090241232
    Abstract: A localized nanostructure growth apparatus that has a partitioned chamber is provided, where a first partition includes a scanning probe microscope (SPM) and a second partition includes an atomic layer deposition (ALD) chamber, where the first partition is hermetically isolated from the second partition, and at least one SPM probe tip of the SPM is disposed proximal to a sample in the ALD chamber. According to the invention, the hermetic isolation between the chambers prevents precursor vapor from damaging critical microscope components and ensuring that contaminants in the ALD chamber can be minimized.
    Type: Application
    Filed: March 23, 2009
    Publication date: September 24, 2009
    Inventors: James F. Mack, Neil Dasgupta, Timothy P. Holme, Friedrich B. Prinz, Andrei Iancu, Wonyoung Lee