Patents by Inventor Sidlgata V. Sreenivasan

Sidlgata V. Sreenivasan 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).

  • Device for holding a template for use in imprint lithography
    Patent number: 8033814
    Abstract: An imprint lithography template may be used to form an imprinted layer in a light curable liquid disposed on a substrate. During use, the template may be disposed within a template holder. The template holder may include a body with an opening configured to receive the template, a support plate, and an actuator system coupled to the body. The actuator system may be configured to alter a physical dimension of the template during use.
    Type: Grant
    Filed: March 2, 2010
    Date of Patent: October 11, 2011
    Assignee: Board of Regents, The University of Texas System
    Inventors: Todd C. Bailey, Byung-Jin Choi, Matthew E. Colburn, Sidlgata V. Sreenivasan, Carlton Grant Willson, John G. Ekerdt
  • Preserving filled features when vacuum wiping
    Patent number: 8021594
    Abstract: A method/process for curing imprint on a template prior to contact with a substrate. A curing process is used to adhere the imprint to a wafer or substrate. Monomer is deposited on a template and then partially cured using a UV exposure. The exposure is controlled so that the imprint is cured past the gel point, but still retains a thin liquid layer of uncured monomer at the surface that will bond with the wafer. Further, this partially cured layer enables the alignment adjustments between the template and the substrate to be performed after contact between the two without pulling any monomer out of the features.
    Type: Grant
    Filed: June 22, 2009
    Date of Patent: September 20, 2011
    Assignee: Molecular Imprints, Inc.
    Inventors: Steven C. Shackleton, Pankaj B. Lad, Ian Matthew McMackin, Frank Y. Xu, Sidlgata V. Sreenivasan
  • Step and Repeat Imprint Lithography Process
    Publication number: 20110221095
    Abstract: The present invention is directed to methods for patterning a substrate by imprint lithography. Imprint lithography is a process in which a liquid is dispensed onto a substrate. A template is brought into contact with the liquid and the liquid is cured. The cured liquid includes an imprint of any patterns formed in the template. In one embodiment, the imprint process is designed to imprint only a portion of the substrate. The remainder of the substrate is imprinted by moving the template to a different portion of the template and repeating the imprint lithography process.
    Type: Application
    Filed: May 16, 2011
    Publication date: September 15, 2011
    Applicant: MOLECULAR IMPRINTS, INC.
    Inventors: Sidlgata V. Sreenivasan, Byung J. Choi, Norman E. Schumaker, Ronald D. Voisin, Michael P. C. Watts, Mario J. Meissl
  • Flexure based macro motion translation stage
    Patent number: 8016277
    Abstract: Described are flexure-based high precision positioning stages. The stages are constrained to motion along each axis by a system of symmetrical flexure linkages. The linkages may be formed of link coupled by flexure joints. Magnetic linear servomotors may provide motive force for the stages. In some embodiments, the stages may have no frictional contact joints.
    Type: Grant
    Filed: August 21, 2001
    Date of Patent: September 13, 2011
    Assignee: Board of Regents, The University of Texas System
    Inventors: Byung J. Choi, Sidlgata V. Sreenivasan
  • Template pattern density doubling
    Patent number: 8012394
    Abstract: A sub-master template is patterned to provide at least double the density of features of a master template. The sub-master template and master template may employ the use of alignment marks during the patterning process.
    Type: Grant
    Filed: December 24, 2008
    Date of Patent: September 6, 2011
    Assignee: Molecular Imprints, Inc.
    Inventor: Sidlgata V. Sreenivasan
  • Imprinting of Partial Fields at the Edge of the Wafer
    Publication number: 20110212263
    Abstract: Edge field patterning of a substrate having full fields and partial fields may include patterning using a template having multiple mesas with each mesa corresponding to a field on the substrate. Polymerizable material may be deposited solely between the template and the full fields of the substrate. A non-reactive material may be deposited between the template and partial fields of the substrate.
    Type: Application
    Filed: May 2, 2011
    Publication date: September 1, 2011
    Applicant: MOLECULAR IMPRINTS, INC.
    Inventors: Sidlgata V. Sreenivasan, Byung-Jin Choi
  • NANOIMPRINT LITHOGRAPHY PROCESSES FOR FORMING NANOPARTICLES
    Publication number: 20110190463
    Abstract: A lithography method for forming nanoparticles includes patterning sacrificial material on a multilayer substrate. In some cases, the pattern is transferred to or into a removable layer of the multilayer substrate, and functional material is disposed on the removable layer of the multilayer substrate and solidified. At least a portion of the functional material is then removed to expose protrusions of the removable layer, and pillars of the functional material are released from the removable layer to yield nanoparticles. In other cases, the multilayer substrate includes the functional material, and the pattern is transferred to or into a removable layer of the multilayer substrate. The sacrificial layer is removed, and pillars of the functional material are released from the removable layer to yield nanoparticles.
    Type: Application
    Filed: January 31, 2011
    Publication date: August 4, 2011
    Applicant: MOLECULAR IMPRINTS, INC.
    Inventors: Frank Y. Xu, Sidlgata V. Sreenivasan
  • METHODS AND SYSTEMS OF MATERIAL REMOVAL AND PATTERN TRANSFER
    Publication number: 20110183521
    Abstract: Polymerized material on a substrate may be removed by exposure to vacuum ultraviolet (VUV) radiation from an energy source within a gaseous atmosphere of a controlled composition. Following such removal, additional etching techniques are also described for nano-imprinting.
    Type: Application
    Filed: January 26, 2011
    Publication date: July 28, 2011
    Applicant: MOLECULAR IMPRINTS, INC.
    Inventors: Gerard M. Schmid, Michael N. Miller, Byung-Jin Choi, Douglas J. Resnick, Sidlgata V. Sreenivasan, Frank Y. Xu, Darren D. Donaldson
  • SOLAR CELL FABRICATION BY NANOIMPRINT LITHOGRAPHY
    Publication number: 20110180127
    Abstract: Fabricating a solar cell stack includes forming a nanopatterned polymeric layer on a first surface of a silicon wafer and etching the first surface of the silicon wafer to transfer a pattern of the nanopatterned polymeric layer to the first surface of the silicon wafer. A layer of reflective electrode material is formed on a second surface of the silicon wafer. The nanopatterned first surface of the silicon wafer undergoes a buffered oxide etching. After the buffered oxide etching, the nanopatterned first surface of the silicon wafer is treated to decrease a contact angle of water on the nanopatterned first surface. Electron donor material is deposited on the nanopatterned first surface of the silicon wafer to form an electron donor layer, and a transparent electrode material is deposited on the electron donor layer to form a transparent electrode layer on the electron donor layer.
    Type: Application
    Filed: January 28, 2011
    Publication date: July 28, 2011
    Applicant: MOLECULAR IMPRINTS, INC.
    Inventors: Fen Wan, Shuqiang Yang, Frank Y. Xu, Weijun Liu, Edward Brian Fletcher, Sidlgata V. Sreenivasan, Michael N. Miller, Darren D. Donaldson
  • Template Having a Varying Thickness to Facilitate Expelling a Gas Positioned Between a Substrate and the Template
    Publication number: 20110171340
    Abstract: A nanoimprint lithography template including, inter alia, a body having first and second opposed sides with a first surface disposed on the first side, the second side having a recess disposed therein, the body having first and second regions with the second region surrounding the first region and the recess in superimposition with the first region, with a portion of the first surface in superimposition with the first region being spaced-apart from the second side a first distance and a portion of the first surface in superimposition with the second region being spaced-apart from the second side a second distance, with the second distance being greater than the first distance; and a mold disposed on the first side of the body in superimposition a portion of the first region.
    Type: Application
    Filed: March 28, 2011
    Publication date: July 14, 2011
    Applicant: MOLECULAR IMPRINTS, INC.
    Inventors: Douglas J. Resnick, Mario J. Meissl, Byung-Jin Choi, Sidlgata V. Sreenivasan
  • Capillary Imprinting Technique
    Publication number: 20110140302
    Abstract: The present invention provides a method for patterning a substrate with a template having a mold that features positioning conformable material between the substrate and the mold and filling a volume defined between the mold and the substrate with the conformable material through capillary action between the conformable material and one of the mold and the substrate. Thereafter, the conformable material is solidified. Specifically, the distance between the mold and the substrate is controlled to a sufficient degree to attenuate, if not avoid, compressive forces between the mold and the substrate. As a result, upon initial contact of the mold with the conformable material, capillary filling of the volume between the mold and the substrate occurs.
    Type: Application
    Filed: February 16, 2011
    Publication date: June 16, 2011
    Applicant: MOLECULAR IMPRINTS, INC.
    Inventors: Byung-Jin Choi, Sidlgata V. Sreenivasan
  • Positive tone bi-layer method
    Patent number: 7947608
    Abstract: Methods of imprint lithography are described. Generally, the methods include imprinting, via a patterned mold, a pattern into a polymerizable fluid composition on a substrate to form a patterned imprinting layer. A conformal layer is overlayed on the patterned imprinting layer. A portion of the conformal layer is used as a hard mask for subsequent processing. The imprinted pattern may be transferred to the substrate by a plurality of etches.
    Type: Grant
    Filed: November 15, 2010
    Date of Patent: May 24, 2011
    Assignee: Molecular Imprints, Inc.
    Inventor: Sidlgata V. Sreenivasan
  • Step and repeat imprint lithography processes
    Patent number: 7943081
    Abstract: Methods of forming continuous layers on regions of a substrate are described. Generally, an imprint lithography template may contact liquid positioned on the substrate. The liquid may be cured forming a masking layer, and the imprint lithography template separated from the masking layer. Prior to separation, pressurized gas and/or vacuum may be applied between the template and the substrate. Additionally, during separation, pressurized gas and/or vacuum may be applied between the template and the substrate.
    Type: Grant
    Filed: April 19, 2010
    Date of Patent: May 17, 2011
    Assignee: Molecular Imprints, Inc.
    Inventors: Sidlgata V. Sreenivasan, Byung-Jin Choi, Norman E. Schumaker, Ronald D. Voisin, Michael P. C. Watts, Mario Johannes Meissl
  • Imprinting of partial fields at the edge of the wafer
    Patent number: 7935292
    Abstract: Edge field patterning of a substrate having full fields and partial fields may include patterning using a template having multiple mesas with each mesa corresponding to a field on the substrate. Polymerizable material may be deposited solely between the template and the full fields of the substrate. A non-reactive material may be deposited between the template and partial fields of the substrate.
    Type: Grant
    Filed: June 5, 2009
    Date of Patent: May 3, 2011
    Assignee: Molecular Imprints, Inc.
    Inventors: Sidlgata V. Sreenivasan, Byung-Jin Choi
  • Full-wafer or large area imprinting with multiple separated sub-fields for high throughput lithography
    Patent number: 7927541
    Abstract: A layer on a substrate is formed using an imprint lithography system. The layer is formed by providing a plurality of flowable regions on the substrate, spreading material in the flowable regions, and contacting the regions with a plurality of imprint lithography molds that are disposed on a template.
    Type: Grant
    Filed: April 27, 2009
    Date of Patent: April 19, 2011
    Assignee: Molecular Imprints, Inc.
    Inventor: Sidlgata V. Sreenivasan
  • LARGE AREA LINEAR ARRAY NANOIMPRINTING
    Publication number: 20110084417
    Abstract: Systems and methods for imprinting and aligning an imprint lithography template with a field on a substrate are described. The field of the substrate may include an elongated side, and alignment sensitivity on the elongated side may be intentionally minimized.
    Type: Application
    Filed: October 7, 2010
    Publication date: April 14, 2011
    Applicant: MOLECULAR IMPRINTS, INC.
    Inventors: Byung-Jin Choi, Sidlgata V. Sreenivasan, Anshuman Cherala
  • Capillary imprinting technique
    Patent number: 7910042
    Abstract: The present invention provides a method for patterning a substrate with a template having a mold that features positioning conformable material between the substrate and the mold and filling a volume defined between the mold and the substrate with the conformable material through capillary action between the conformable material and one of the mold and the substrate. Thereafter, the conformable material is solidified. Specifically, the distance between the mold and the substrate is controlled to a sufficient degree to attenuate, if not avoid, compressive forces between the mold and the substrate. As a result, upon initial contact of the mold with the conformable material, spontaneous capillary filling of the volume between the mold and the substrate occurs.
    Type: Grant
    Filed: February 17, 2010
    Date of Patent: March 22, 2011
    Assignee: Molecular Imprints, Inc.
    Inventors: Byung-Jin Choi, Sidlgata V. Sreenivasan
  • Positive Tone Bi-Layer Method
    Publication number: 20110056911
    Abstract: Methods of imprint lithography are described. Generally, the methods include imprinting, via a patterned mold, a pattern into a polymerizable fluid composition on a substrate to form a patterned imprinting layer. A conformal layer is overlayed on the patterned imprinting layer. A portion of the conformal layer is used as a hard mask for subsequent processing. The imprinted pattern may be transferred to the substrate by a plurality of etches.
    Type: Application
    Filed: November 15, 2010
    Publication date: March 10, 2011
    Applicant: MOLECULAR IMPRINTS, INC.
    Inventor: Sidlgata V. Sreenivasan
  • Nanostructured thin film inorganic solar cells
    Publication number: 20110048518
    Abstract: Inorganic solar cells having a nano-patterned p-n or p-i-n junction to reduce electron and hole travel distance to the separation interface to be less than the magnitude of the drift length or diffusion length, and meanwhile to maintain adequate active material to absorb photons. Formation of the inorganic solar cells may include one or more nano-lithography steps.
    Type: Application
    Filed: August 17, 2010
    Publication date: March 3, 2011
    Applicants: MOLECULAR IMPRINTS, INC., BOARD OF REGENTS, THE UNIVERSITY OF TEXAS SYSTEM
    Inventors: Shuqiang Yang, Sidlgata V. Sreenivasan, Frank Y. Xu
  • Functional Nanoparticles
    Publication number: 20110049096
    Abstract: Functional nanoparticles may be formed using at least one nano-lithography step. In one embodiment, sacrificial material may be patterned on a multi-layer substrate using an imprint lithography system. The pattern may be further etched into the multi-layer substrate. Functional material may then be deposited on multi-layer substrate and solidified. At least a portion of the functional material may then be removed to provide a crown surface exposing pillars. Pillars may be removed from multi-layer substrate forming functional nanoparticles.
    Type: Application
    Filed: August 11, 2010
    Publication date: March 3, 2011
    Applicants: BOARD OF REGENTS, THE UNIVERSITY OF TEXAS SYSTEM, MOLECULAR IMPRINTS, INC.
    Inventors: Sidlgata V. Sreenivasan, Shuqiang Yang, Frank Y. Xu, Vikramjit Singh