Patents by Inventor Kunal Taravade

Kunal Taravade 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: 7149340
    Abstract: A method and system for detecting defects in a physical mask used for fabricating a semiconductor device having multiple layers is disclosed, where each layer has a corresponding mask. The method and system include receiving a digital image of the mask, and automatically detecting edges of the mask in the image using pattern recognition. The detected edges, which are stored in a standard format, are imported along with processing parameters into a process simulator that generates an estimated aerial image of the silicon layout that would be produced by a scanner using the mask and the parameters. The estimated aerial image is then compared to an intended aerial image of the same layer, and any differences found that are greater than predefined tolerances are determined to horizontal defects. In addition, effects that the horizontal defects may have on adjacent layers are analyzed to discover vertical defects.
    Type: Grant
    Filed: September 20, 2002
    Date of Patent: December 12, 2006
    Assignee: LSI Logic Corporation
    Inventors: Paul Filseth, Neal Callan, Kunal Taravade, Mario Garza
  • Publication number: 20060188793
    Abstract: A phase shift mask having transmission properties that are dependent at least in part on an intensity of an incident light beam. The phase shift mask has a mask substrate that is substantially transparent to the incident light beam. A first phase shift layer is disposed on the mask substrate. The first phase shift layer has a refractive index that is nonlinear with the intensity of the incident light beam. The refractive index of the first phase shift layer changes with the intensity of the incident light beam on the phase shift mask. By using a first phase shift layer on the phase shift mask that has a refractive index that is non linear with the intensity of the incident light beam, properties of a light beam transmitted through the first phase shift layer, such as interference patterns in the transmitted light beam, can be adjusted by adjusting the intensity of the incident light beam.
    Type: Application
    Filed: May 3, 2006
    Publication date: August 24, 2006
    Applicant: LSI Logic Corporation
    Inventors: Kunal Taravade, Dodd Defibaugh
  • Publication number: 20060105564
    Abstract: The present invention is directed to a method and system of intelligent dummy filling placement to reduce inter-layer capacitance caused by overlaps of dummy filling area on successive layers. The method and system treats each consecutive pair of layers together so as to minimize dummy filling overlaps between each layer. In particular, dummy fill features on each layer may be placed in a checkerboard pattern to avoid overlaps. As such, the present invention may eliminate large overlap area of the dummy patterns on consecutive layers by utilizing intelligent dummy filling placement.
    Type: Application
    Filed: November 17, 2004
    Publication date: May 18, 2006
    Inventors: Kunal Taravade, Neal Callan, Paul Filseth
  • Publication number: 20050112478
    Abstract: A phase shift mask having transmission properties that are dependent at least in part on an intensity of an incident light beam. The phase shift mask has a mask substrate that is substantially transparent to the incident light beam. A first phase shift layer is disposed on the mask substrate. The first phase shift layer has a refractive index that is nonlinear with the intensity of the incident light beam. The refractive index of the first phase shift layer changes with the intensity of the incident light beam on the phase shift mask. By using a first phase shift layer on the phase shift mask that has a refractive index that is non linear with the intensity of the incident light beam, properties of a light beam transmitted through the first phase shift layer, such as interference patterns in the transmitted light beam, can be adjusted by adjusting the intensity of the incident light beam.
    Type: Application
    Filed: October 25, 2004
    Publication date: May 26, 2005
    Inventors: Kunal Taravade, Dodd Defibaugh
  • Patent number: 6864020
    Abstract: An attenuated phase shift mask is formed using a non-linear optical material for both fiducial features and pattern features. The non-linear optical material selected has predetermined transmission at the actinic exposure wavelength and a smaller transmission at the fiducial recognition wavelengths.
    Type: Grant
    Filed: December 24, 2002
    Date of Patent: March 8, 2005
    Assignee: LSI Logic Corporation
    Inventors: Kunal Taravade, Neal Callan
  • Publication number: 20050019673
    Abstract: A phase shift mask which includes an etched quartz region that provides a 180 degree phase shift, and an attenuated film which provides a 0 (or 360) degree phase shift. The phase shift mask provides performance comparable to CPL, while at the same time, avoiding the problems and manufacturability issues associated with EDA. The phase shift mask has better contrast than CPL, and a process window that is comparable to both CPL and alternating phase shift masks. The phase shift mask that does not require a second critical write, as is the case with CPL, does not need a second mask to eliminate unwanted patterns resulting from phase edges, and does not need a complicated EDA solution (like CPL). Finally, the phase shift mask is simple to manufacture, requiring only a single write step if employed with the back-side exposure technique which is well known in the mask-making industry.
    Type: Application
    Filed: July 22, 2003
    Publication date: January 27, 2005
    Inventors: Kunal Taravade, Ebo Croffie, Neal Callan
  • Publication number: 20050014075
    Abstract: A binary mask and method for improving the aerial image and mask error enhancement factor (MEEF) of binary masks. A phase edge darkening binary mask is provided which has quartz etched, preferably at a depth which corresponds to a phase shift of 180 degrees. A method of manufacturing a phase edge darkening binary mask is also provided, where the method consists of changing the phase of the layout background by etching to take advantage of the phase edge darkening as a result of light leakage through chrome.
    Type: Application
    Filed: July 18, 2003
    Publication date: January 20, 2005
    Inventors: Ebo Croffie, Kunal Taravade, Nicholas Eib
  • Patent number: 6775818
    Abstract: A circuit, gate, or device parameter simulation includes data on the initial conditions of manufacture, including illumination conditions on a stepper, material parameters for processing conditions, and chip layout. Optical effects and processing tolerances may be accounted for in the simulation of the final device performance characteristics. The circuit, gate, or device parameter simulation may incorporate optical proximity code software. Simulated active and passive components are generated by the circuit, gate, or device parameter simulation from the simulated patterned layers on the substrate. Feedback may be provided to the circuit, gate, or device parameter simulation to optimize performance.
    Type: Grant
    Filed: August 20, 2002
    Date of Patent: August 10, 2004
    Assignee: LSI Logic Corporation
    Inventors: Kunal Taravade, Neal Callan, Nadya Strelkova
  • Publication number: 20040057610
    Abstract: A method and system for detecting defects in a physical mask used for fabricating a semiconductor device having multiple layers is disclosed, where each layer has a corresponding mask. The method and system include receiving a digital image of the mask, and automatically detecting edges of the mask in the image using pattern recognition. The detected edges, which are stored in a standard format, are imported along with processing parameters into a process simulator that generates an estimated aerial image of the silicon layout that would be produced by a scanner using the mask and the parameters. The estimated aerial image is then compared to an intended aerial image of the same layer, and any differences found that are greater than predefined tolerances are determined to horizontal defects. In addition, effects that the horizontal defects may have on adjacent layers are analyzed to discover vertical defects.
    Type: Application
    Filed: September 20, 2002
    Publication date: March 25, 2004
    Inventors: Paul Filseth, Neal Callan, Kunal Taravade, Mario Garza
  • Publication number: 20040040000
    Abstract: A circuit, gate, or device parameter simulation includes data on the initial conditions of manufacture, including illumination conditions on a stepper, material parameters for processing conditions, and chip layout. Optical effects and processing tolerances may be accounted for in the simulation of the final device performance characteristics. The circuit, gate, or device parameter simulation may incorporate optical proximity code software. Simulated active and passive components are generated by the circuit, gate, or device parameter simulation from the simulated patterned layers on the substrate. Feedback may be provided to the circuit, gate, or device parameter simulation to optimize performance.
    Type: Application
    Filed: August 20, 2002
    Publication date: February 26, 2004
    Inventors: Kunal Taravade, Neal Callan, Nadya Strelkova
  • Patent number: 6527867
    Abstract: A method of fabricating an integrated circuit using photolithography and an antireflective coating. An antireflective coating is formed on a substrate wherein the antireflective coating is electrically polarizable. A photoresist coating is formed on the antireflective coating on a side opposite from the substrate and the photoresist is exposed to activating radiation. The antireflective coating is subjected to an applied electric field at substantially the same time as the photoresist is exposed to activating radiation. The radiation absorption coefficient of said antireflective coating is increased and the refractive index of said antireflective coating is changed to be substantially equal to the refractive index of said photoresist coating.
    Type: Grant
    Filed: May 30, 2000
    Date of Patent: March 4, 2003
    Assignee: LSI Logic Corporation
    Inventors: Kunal Taravade, Gayle Miller, Gail Shelton
  • Patent number: 6441419
    Abstract: An integrated circuit includes a vertical-interdigitated capacitor located between an upper interconnect layer and a lower interconnect layer. Both interconnect layers include conductors formed of a metal capable of atom diffusion or ion migration, such as copper. The capacitor plates contact an interconnect layer conductor to create barrier layers to prevent atom diffusion or ion migration from the conductors at the contact locations. Additional barrier layers contact the conductors at locations other than where the capacitor plate portions contact the conductors, and the additional barrier layers are preferably formed of the same material and at the same time that one of the plates is formed. The integrated circuit may include a via plug interconnect extending between conductors of upper and lower interconnect layers, with a plug barrier layer surrounding the plug material to prevent atom diffusion or ion migration from the plug material.
    Type: Grant
    Filed: March 15, 2000
    Date of Patent: August 27, 2002
    Assignee: LSI Logic Corporation
    Inventors: Gregory A. Johnson, Kunal Taravade, Gayle Miller
  • Patent number: 6225215
    Abstract: A method of fabricating an integrated circuit using photolithography and an antireflective coating. An antireflective coating is formed on a substrate wherein the antireflective coating is electrically polarizable. A photoresist coating is formed on the antireflective coating on a side opposite from the substrate and the photoresist is exposed to activating radiation. The antireflective coating is subjected to an applied electric field at substantially the same time as the photoresist is exposed to activating radiation. The radiation absorption coefficient of said antireflective coating is increased and the refractive index of said antireflective coating is changed to be substantially equal to the refractive index of said photoresist coating.
    Type: Grant
    Filed: September 24, 1999
    Date of Patent: May 1, 2001
    Assignee: LSI Logic Corporation
    Inventors: Kunal Taravade, Gayle Miller, Gail Shelton