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).

  • Patent number: 8387482
    Abstract: Systems to control movement of a template during an imprint lithography process are described. The systems include an orientation stage having an inner frame, and outer frame, and a plurality of actuators coupled between the inner frame and the outer frame to vary translational motion and impart angular motion about a plurality of axes.
    Type: Grant
    Filed: November 9, 2010
    Date of Patent: March 5, 2013
    Assignee: Molecular Imprints, Inc.
    Inventors: Byung-Jin Choi, Sidlgata V. Sreenivasan
  • Patent number: 8349241
    Abstract: The present invention is directed to a method of and a mold for arranging features on a substrate to replicate the features with minimal dimensional variability. The method includes arranging features on a layer to minimize thickness variations in the layer that are attributable to density variations of the plurality of features on the layer. The features are transferred into an underlying substrate. It is believed that by forming the features so as to define a uniform fill factor in the layer, the thickness variations may be reduced, if not abrogated. To that end, one method in accordance with the present invention includes forming a flowable material on the substrate. Thereafter, a plurality of features is formed in a region of the flowable material. The plurality of features are arranged to provide a substantially uniform fill factor in the region.
    Type: Grant
    Filed: October 4, 2002
    Date of Patent: January 8, 2013
    Assignee: Molecular Imprints, Inc.
    Inventors: Sidlgata V. Sreenivasan, Michael P. C. Watts
  • Patent number: 8334967
    Abstract: The present invention includes a substrate support system having a chuck body. The chuck body includes a body surface with a pin extending therefrom having a contact surface lying in a plane. The pin may be movably coupled to the chuck body to move with respect to the plane. The pin may also include a cross-member having multiple contact lands.
    Type: Grant
    Filed: August 27, 2009
    Date of Patent: December 18, 2012
    Assignee: Board of Regents, The University of Texas System
    Inventors: Pawan Kumar Nimmakayala, Sidlgata V. Sreenivasan
  • Patent number: 8318066
    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: Grant
    Filed: May 16, 2011
    Date of Patent: November 27, 2012
    Assignee: Molecular Imprints, Inc.
    Inventors: Sidlgata V. Sreenivasan, Byung-Jin Choi, Norman E. Schumaker, Ronald D. Voisin, Michael P. C. Watts, Mario Johannes Meissl
  • Patent number: 8282383
    Abstract: The present invention is directed towards a system for expelling a gas positioned between a substrate and a mold, the substrate and the mold further having a liquid positioned therebetween.
    Type: Grant
    Filed: February 17, 2010
    Date of Patent: October 9, 2012
    Assignee: Molecular Imprints, Inc.
    Inventors: Byung-Jin Choi, Sidlgata V. Sreenivasan, Ian Matthew McMackin, Pankaj B. Lad
  • Publication number: 20120214066
    Abstract: A silicon nanowire array including a multiplicity of silicon nanowires extending from a silicon substrate. Cross-sectional shape of the silicon nanowires and spacing between the silicon nanowires can be selected to maximize the ratio of the surface area of the silicon nanowires to the volume of the nanowire array. Methods of forming the silicon nanowire array include a nanoimprint lithography process to form a template for the silicon nanowire array and an electroless etching process to etch the template formed by the nanoimprint lithography process.
    Type: Application
    Filed: February 16, 2012
    Publication date: August 23, 2012
    Applicants: BOARD OF REGENTS, THE UNIVERSITY OF TEXAS SYSTEM, MOLECULAR IMPRINTS, INC.
    Inventors: Michael N. Miller, Fen Wan, Vikramjit Singh, Darren D. Donaldson, Gerard M. Schmid, Sidlgata V. Sreenivasan, Frank Y. Xu
  • Publication number: 20120187085
    Abstract: Thickness of a residual layer may be altered to control critical dimension of features in a patterned layer provided by an imprint lithography process. The thickness of the residual layer may be directly proportional or inversely proportional to the critical dimension of features. Dispensing techniques and material selection may also provide control of the critical dimension of features in the patterned layer.
    Type: Application
    Filed: April 6, 2012
    Publication date: July 26, 2012
    Applicant: Molecular Imprints, Inc.
    Inventors: Cynthia B. Brooks, Dwayne L. LaBrake, Niyaz Khusnatdinov, Michael N. Miller, Sidlgata V. Sreenivasan, David James Lentz, Frank Y. Xu
  • Patent number: 8187515
    Abstract: Droplets of polymerizable material may be patterned on a film sheet. The droplets of polymerizable material may be dispensed on the film sheet. A pre-determined force may be applied to an imprint lithography template such that localized trapping of the droplets of the polymerizable material on the film sheet is minimized and the droplets coalesce to form a continuous layer. The polymerizable material may be solidified to form a patterned layer having a residual layer and at least one feature.
    Type: Grant
    Filed: March 31, 2009
    Date of Patent: May 29, 2012
    Assignees: Molecular Imprints, Inc., Board of Regents, The University of Texas
    Inventors: Sidlgata V. Sreenivasan, Shrawan Singhal, Byung Jin Choi, Ian Matthew McMackin
  • Publication number: 20120112385
    Abstract: Methods of making nano-scale structures with geometric cross-sections, including convex or non-convex cross-sections, are described. The approach may be used to directly pattern substrates and/or create imprint lithography templates or molds that may be subsequently used to directly replicate nano-shaped patterns into other substrates, such as into a functional or sacrificial resist to form functional nanoparticles.
    Type: Application
    Filed: November 7, 2011
    Publication date: May 10, 2012
    Applicants: BOARD OF REGENTS, THE UNIVERSITY OF TEXAS SYSTEM, MOLECULAR IMPRINTS, INC.
    Inventors: Sidlgata V. Sreenivasan, Vikramjit Singh, Frank Y. Xu, Byung-Jin Choi
  • Publication number: 20120114559
    Abstract: Functional nanoparticles may be formed using at least one nanoimprint lithography step. In one embodiment, sacrificial material may be patterned on a multilayer substrate including one or more functional layers between removable layers using an imprint lithography process. At least one of the functional layers includes a functional material such as a pharmaceutical composition or imaging agent. The pattern may be further etched into the multilayer substrate. At least a portion of the functional material may then be removed to provide a crown surface exposing pillars. Removing the removable layers releases the pillars from the patterned structure to form functional nanoparticles such as drug or imaging agent carriers.
    Type: Application
    Filed: November 4, 2011
    Publication date: May 10, 2012
    Applicants: BOARD OF REGENTS, THE UNIVERSITY OF TEXAS SYSTEM, MOLECULAR IMPRINTS, INC.
    Inventors: Vikramjit Singh, Frank Y. Xu, Sidlgata V. Sreenivasan
  • Patent number: 8142850
    Abstract: A method of patterning a substrate comprising a plurality of fields, including, inter alia, positioning a first volume of fluid on a first subset of the plurality of fields of the substrate, with the first volume of fluid being subjected to a first evaporation time; positioning a second volume of fluid on a second subset of the plurality of fields of the substrate, differing from the first subset, with the second volume of fluid being subjected to a second evaporation time, differing from the first evaporation time; and patterning the first and second subsets of the plurality of fields, with the first subset of the plurality of fields being patterned prior to the second subset of the plurality of fields being patterned, with a volume associated with the second subset of the plurality of fields being greater than a volume associated with the first subset of the plurality of fields to compensate for the second evaporation time being greater than the first evaporation time.
    Type: Grant
    Filed: March 28, 2007
    Date of Patent: March 27, 2012
    Assignee: Molecular Imprints, Inc.
    Inventors: Sidlgata V. Sreenivasan, Philip D. Schumaker
  • Patent number: 8123514
    Abstract: The present invention includes a template for patterning liquids disposed on a substrate. The template includes a body having opposed first and second surfaces with one surface having at least one recess and the other surface having a patterning region. In one embodiment, the template may be mounted to a fluid chamber having an inlet and a throughway. The template may be connected to the throughway and the inlet is connected to a fluid source.
    Type: Grant
    Filed: March 4, 2010
    Date of Patent: February 28, 2012
    Assignee: Molecular Imprints, Inc.
    Inventors: Sidlgata V. Sreenivasan, Byung-Jin Choi, Ronald D. Voisin
  • Patent number: 8109753
    Abstract: A nano-imprint lithography system is described for patterning first and second substrates, the system includes a translation stage constructed to alternatively place substrate chucks in position with respect to a nano-imprint mold assembly such that the nano-imprint mold assembly may imprint a pattern on one of the substrates, while concurrently obtaining a desired spatial relationship for the remaining substrate.
    Type: Grant
    Filed: January 8, 2010
    Date of Patent: February 7, 2012
    Assignee: Molecular Imprints, Inc.
    Inventors: Byung-Jin Choi, Sidlgata V. Sreenivasan
  • Patent number: 8109754
    Abstract: A system of patterning first and second opposed sides of a substrate is described. The system may employ a mold assembly and obtaining a desired spatial relationship between the first and second opposed sides of the substrate and the mold assembly. In a further embodiment, the method and system may employ a first and a second mold assembly.
    Type: Grant
    Filed: January 13, 2010
    Date of Patent: February 7, 2012
    Assignee: Molecular Imprints, Inc.
    Inventors: Byung-Jin Choi, Sidlgata V. Sreenivasan
  • Patent number: 8075299
    Abstract: Separation of an imprint lithography template and a patterned layer in an imprint lithography process may result in stress to features of the template and/or features of the patterned layer. Such stress may be reduced by minimizing open areas on the template, including dummy features within the open areas, and/or selective positioning of features on the template.
    Type: Grant
    Filed: October 19, 2009
    Date of Patent: December 13, 2011
    Assignee: Molecular Imprints, Inc.
    Inventors: Frank Y. Xu, Sidlgata V. Sreenivasan
  • Patent number: 8066930
    Abstract: The present invention is directed to a method of forming an imprinting layer on a substrate including high resolution features, and transferring the features into a solidified region of the substrate. Desired thickness of the residual layer may be minimized in addition to visco-elastic behavior of the material.
    Type: Grant
    Filed: March 30, 2010
    Date of Patent: November 29, 2011
    Assignee: Molecular Imprints, Inc.
    Inventors: Sidlgata V. Sreenivasan, Michael P. C. Watts
  • Publication number: 20110277833
    Abstract: Variations of interdigitated backside contact (IBC) solar cells having patterned areas formed using nano imprint lithography are described.
    Type: Application
    Filed: May 11, 2011
    Publication date: November 17, 2011
    Applicant: Molecular Imprints, Inc.
    Inventors: Michael N. Miller, Sidlgata V. Sreenivasan, Frank Y. Xu, Gerard M. Schmid
  • Publication number: 20110277827
    Abstract: Systems and methods for fabrication of nanostructured solar cells having arrays of nanostructures are described, including nanostructured solar cells having a repeating pattern of pyramid nanostructures, providing for low cost thin-film solar cells with improved PCE.
    Type: Application
    Filed: May 11, 2011
    Publication date: November 17, 2011
    Applicants: BOARD OF REGENTS, THE UNIVERSITY OF TEXAS SYSTEM, MOLECULAR IMPRINTS, INC.
    Inventors: Shuqiang Yang, Michael N. Miller, Mohamed M. Hilali, Fen Wan, Gerard M. Schmid, Liang Wang, Sidlgata V. Sreenivasan, Frank Y. Xu
  • Patent number: 8057725
    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: Grant
    Filed: February 16, 2011
    Date of Patent: November 15, 2011
    Assignee: Molecular Imprints, Inc.
    Inventors: Byung-Jin Choi, Sidlgata V. Sreenivasan
  • Publication number: 20110260361
    Abstract: Control of lateral strain and lateral strain ratio (dt/db) between template and substrate through the selection of template and/or substrate thicknesses (Tt and/or Tb), control of template and/or substrate back pressure (Pt and/or Pb), and/or selection of material stiffness are described.
    Type: Application
    Filed: April 27, 2011
    Publication date: October 27, 2011
    Applicant: Molecular Imprints, Inc.
    Inventors: Se-Hyuk Im, Mahadevan GanapathiSubramanian, Edward Brian Fletcher, Niyaz Khusnatdinov, Gerard M. Schmid, Mario Johannes Meissl, Anshuman Cherala, Frank Y. Xu, Byung-Jin Choi, Sidlgata V. Sreenivasan