Patents by Inventor Sairam Shekhar

Sairam Shekhar 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).

  • CMP compositions and methods for selective removal of silicon nitride
    Patent number: 9850402
    Abstract: The present invention provides chemical mechanical polishing compositions and methods for polishing a substrate comprising silicon dioxide and silicon nitride, which provide selective removal of SiN relative to silicon oxide (e.g., PETEOS) on patterned wafers. In one embodiment, a CMP method comprises abrading a surface of a substrate comprising SiN and silicon oxide with a CMP composition to remove at least some SiN therefrom. The CMP composition comprises, consists essentially of, or consists of a particulate abrasive (e.g., ceria) suspended in an aqueous carrier and containing a cationic polymer bearing pendant quaternized nitrogen-heteroaromatic moieties, wherein the composition has a pH of greater than about 3.
    Type: Grant
    Filed: December 9, 2013
    Date of Patent: December 26, 2017
    Assignee: Cabot Microelectronics Corporation
    Inventors: Dmitry Dinega, Sairam Shekhar, Renhe Jia, Daniel Mateja
  • Wet-process ceria compositions for polishing substrates, and methods related thereto
    Patent number: 9281210
    Abstract: Disclosed are a chemical-mechanical polishing composition and a method of polishing a substrate. The polishing composition comprises low average particle size (e.g., 30 nm or less) wet-process ceria abrasive particles, at least one alcohol amine, and water, wherein said polishing composition has a pH of about 6. The polishing composition can be used, e.g., to polish any suitable substrate, such as a polysilicon wafer used in the semiconductor industry.
    Type: Grant
    Filed: October 10, 2013
    Date of Patent: March 8, 2016
    Assignee: Cabot Microelectronics Corporation
    Inventors: Brian Reiss, Jeffrey Dysard, Sairam Shekhar
  • CMP COMPOSITIONS AND METHODS FOR SELECTIVE REMOVAL OF SILICON NITRIDE
    Publication number: 20150159046
    Abstract: The present invention provides chemical mechanical polishing compositions and methods for polishing a substrate comprising silicon dioxide and silicon nitride, which provide selective removal of SiN relative to silicon oxide (e.g., PETEOS) on patterned wafers. In one embodiment, a CMP method comprises abrading a surface of a substrate comprising SiN and silicon oxide with a CMP composition to remove at least some SiN therefrom. The CMP composition comprises, consists essentially of, or consists of a particulate abrasive (e.g., ceria) suspended in an aqueous carrier and containing a cationic polymer bearing pendant quaternized nitrogen-heteroaromatic moieties, wherein the composition has a pH of greater than about 3.
    Type: Application
    Filed: December 9, 2013
    Publication date: June 11, 2015
    Inventors: Dmitry DINEGA, Sairam SHEKHAR, Renhe JIA, Daniel Mateja
  • WET-PROCESS CERIA COMPOSITIONS FOR POLISHING SUBSTRATES, AND METHODS RELATED THERETO
    Publication number: 20150104939
    Abstract: Disclosed are a chemical-mechanical polishing composition and a method of polishing a substrate. The polishing composition comprises low average particle size (e.g., 30 nm or less) wet-process ceria abrasive particles, at least one alcohol amine, and water, wherein said polishing composition has a pH of about 6. The polishing composition can be used, e.g., to polish any suitable substrate, such as a polysilicon wafer used in the semiconductor industry.
    Type: Application
    Filed: October 10, 2013
    Publication date: April 16, 2015
    Applicant: Cabot Miroelectronics Corporation
    Inventors: Brian REISS, Jeffrey Dysard, Sairam Shekhar