Patents by Inventor Vamsi K Devarapalli

Vamsi K Devarapalli 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: 8822340
    Abstract: A colloidal dispersion for chemical mechanical polishing comprising: (a) an abrasive component; and (b) from about 0.05% to about 10% by weight of the abrasive component, a water-soluble amphoteric polymer comprising at least one macromolecular chain B and a part A bonded to a single end of the at least one macromolecular chain B, wherein the macromolecular chain B is derived from one or more ethylenically unsaturated monomers having quaternary ammonium groups or inium groups, and wherein the part A is a polymeric or nonpolymeric group comprising at least one anionic group; wherein the dispersion has a pH of between about 1.5 and about 6. The colloidal dispersion is capable of polishing a substrate comprising silicon nitride and silicon oxide with a reverse selectivity ratio of at least about 27, typically at least 50 the reverse selectivity ratio being the ratio of the rate of removal of the silicon nitride to the rate of removal of the silicon oxide.
    Type: Grant
    Filed: January 3, 2013
    Date of Patent: September 2, 2014
    Assignees: Rhodia Operations, Clarkson University—Division of Research
    Inventors: Suryadevara V. Babu, Pradeepa Dandu, Vamsi K. Devarapalli, Guillaume Criniere, Claire Pitois
  • Publication number: 20130122705
    Abstract: A colloidal dispersion for chemical mechanical polishing comprising: (a) an abrasive component; and (b) from about 0.05% to about 10% by weight of the abrasive component, a water-soluble amphoteric polymer comprising at least one macromolecular chain B and a part A bonded to a single end of the at least one macromolecular chain B, wherein the macromolecular chain B is derived from one or more ethylenically unsaturated monomers having quaternary ammonium groups or inium groups, and wherein the part A is a polymeric or nonpolymeric group comprising at least one anionic group; wherein the dispersion has a pH of between about 1.5 and about 6. The colloidal dispersion is capable of polishing a substrate comprising silicon nitride and silicon oxide with a reverse selectivity ratio of at least about 27, typically at least 50 the reverse selectivity ratio being the ratio of the rate of removal of the silicon nitride to the rate of removal of the silicon oxide.
    Type: Application
    Filed: January 3, 2013
    Publication date: May 16, 2013
    Applicants: Clarkson University, Rhodia Operations
    Inventors: Suryadevara V. BABU, Pradeepa DANDU, Vamsi K. DEVARAPALLI, Guillaume CRINIERE, Claire PITOIS
  • Patent number: 8366959
    Abstract: A colloidal dispersion for chemical mechanical polishing comprising: (a) an abrasive component; and (b) from about 0.05% to about 10% by weight of the abrasive component, a water-soluble amphoteric polymer comprising at least one macromolecular chain B and a part A bonded to a single end of the at least one macromolecular chain B, wherein the macromolecular chain B is derived from one or more ethylenically unsaturated monomers having quaternary ammonium groups or inium groups, and wherein the part A is a polymeric or nonpolymeric group comprising at least one anionic group; wherein the dispersion has a pH of between about 1.5 and about 6. The colloidal dispersion is capable of polishing a substrate comprising silicon nitride and silicon oxide with a reverse selectivity ratio of at least about 27, typically at least 50 the reverse selectivity ratio being the ratio of the rate of removal of the silicon nitride to the rate of removal of the silicon oxide.
    Type: Grant
    Filed: September 25, 2009
    Date of Patent: February 5, 2013
    Assignees: Rhodia Operations, Clarkson University
    Inventors: Suryadevara V. Babu, Pradeepa Dandu, Vamsi K Devarapalli, Guillaume Crinière, Claire Pitois
  • Publication number: 20100081281
    Abstract: A colloidal dispersion for chemical mechanical polishing comprising: (a) an abrasive component; and (b) from about 0.05% to about 10% by weight of the abrasive component, a water-soluble amphoteric polymer comprising at least one macromolecular chain B and a part A bonded to a single end of the at least one macromolecular chain B, wherein the macromolecular chain B is derived from one or more ethylenically unsaturated monomers having quaternary ammonium groups or inium groups, and wherein the part A is a polymeric or nonpolymeric group comprising at least one anionic group; wherein the dispersion has a pH of between about 1.5 and about 6. The colloidal dispersion is capable of polishing a substrate comprising silicon nitride and silicon oxide with a reverse selectivity ratio of at least about 27, typically at least 50 the reverse selectivity ratio being the ratio of the rate of removal of the silicon nitride to the rate of removal of the silicon oxide.
    Type: Application
    Filed: September 25, 2009
    Publication date: April 1, 2010
    Applicants: RHODIA OPERATIONS, CLARKSON UNIVERSITY
    Inventors: Suryadevara V. Babu, Pradeepa Dandu, Vamsi K. Devarapalli, Guillaume Criniere, Claire Pitois