Patents by Inventor Suryadevara V. Babu

Suryadevara V. Babu 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: 9097994
    Abstract: A process for abrasive-free chemical mechanical planarization of silicon thin film coated EUV mask substrates is disclosed. The process removes bumps and pits on the substrate thereby mitigating reflective errors in the mask. The process employs a two-step polishing procedure, in which the second step is abrasive-free and uses an amine or amine salt as the polishing agent.
    Type: Grant
    Filed: January 25, 2013
    Date of Patent: August 4, 2015
    Assignees: Sematech, Inc., Clarkson University
    Inventors: Suryadevara V. Babu, Hariprasad Amanapu, Uma Rames Krishna Laguda, Ranganath Teki
  • 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: 20130209924
    Abstract: A process for abrasive-free chemical mechanical planarization of silicon thin film coated EUV mask substrates is disclosed. The process removes bumps and pits on the substrate thereby mitigating reflective errors in the mask. The process employs a two-step polishing procedure, in which the second step is abrasive-free and uses an amine or amine salt as the polishing agent.
    Type: Application
    Filed: January 25, 2013
    Publication date: August 15, 2013
    Inventors: Suryadevara V. BABU, Hariprasad AMANAPU, Uma Rames Krishna LAGUDA, Ranganath TEKI
  • 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: 20120190200
    Abstract: A chemical mechanical planarization method uses a chemical mechanical planarization composition that includes at least one nitrogen containing material and a pH modifying material, absent an abrasive material. The nitrogen containing material may be selected from a particular group of nitrogen containing polymers and corresponding nitrogen containing monomers. The chemical mechanical planarization method and the chemical mechanical planarization composition provide for planarizing a silicon material layer, such as but not limited to a poly-Si layer, in the presence of a silicon containing dielectric material layer, such as but not limited to a silicon oxide layer or a silicon nitride layer, with enhanced efficiency provided by an enhanced removal rate ratio.
    Type: Application
    Filed: January 24, 2012
    Publication date: July 26, 2012
    Applicant: CLARKSON UNIVERSITY
    Inventors: Naresh K. Penta, Suryadevara V. Babu
  • Patent number: 7723234
    Abstract: A method of removing polysilicon in preference to silicon dioxide and/or silicon nitride by chemical mechanical polishing. The method removes polysilicon from a surface at a high removal rate while maintaining a high selectivity of polysilicon to silicon dioxide and/or a polysilicon to silicon nitride. The method is particularly suitable for use in the fabrication of MEMS devices.
    Type: Grant
    Filed: November 22, 2006
    Date of Patent: May 25, 2010
    Assignees: Clarkson University, Infotonics Technology Center Inc.
    Inventors: Suryadevara V. Babu, Anita Natarajan, Sharath Hegde
  • 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
  • Patent number: 7629258
    Abstract: The present invention provides a method of removing silicon nitride at about the same removal rate as silicon dioxide by CMP. The method utilizes a polishing slurry that includes colloidal silica abrasive particles dispersed in water and additives that modulate the silicon dioxide and silicon nitride removal rates such that they are about the same. In one embodiment of the invention, the additive is lysine or lysine mono hydrochloride in combination with picolinic acid, which is effective at a pH of about 8. In another embodiment of the invention, the additive is arginine in combination with picolinic acid, which is effective at a pH of about 10.
    Type: Grant
    Filed: November 22, 2006
    Date of Patent: December 8, 2009
    Assignees: Clarkson University, Infotonics Technology Center Inc.
    Inventors: Suryadevara V. Babu, Anita Natarajan
  • Publication number: 20090176371
    Abstract: The present invention provides a method of removing silicon nitride in preference to silicon dioxide by CMP. The method utilizes a polishing slurry that includes colloidal silica abrasive particles dispersed in water and an additive that suppresses the silicon dioxide removal rate but enhances the silicon nitride removal rate. In one embodiment of the invention, the additive is lysine, which is effective at a pH of about 9, or arginine, which is effective at a pH of about 8. In another embodiment of the invention, the additive is lysine mono hydrochloride in combination with picolinic acid, which is effective at a pH of about 8, or arginine in combination with picolinic acid, which is effective at a pH of about 9.
    Type: Application
    Filed: November 7, 2008
    Publication date: July 9, 2009
    Applicants: CLARKSON UNIVERSITY, INFOTONICS TECHNOLOGY CENTER INC.
    Inventors: Suryadevara V. Babu, Anita Natarajan
  • Publication number: 20080116172
    Abstract: The present invention provides a method of removing silicon nitride at about the same removal rate as silicon dioxide by CMP. The method utilizes a polishing slurry that includes colloidal silica abrasive particles dispersed in water and additives that modulate the silicon dioxide and silicon nitride removal rates such that they are about the same. In one embodiment of the invention, the additive is lysine or lysine mono hydrochloride in combination with picolinic acid, which is effective at a pH of about 8. In another embodiment of the invention, the additive is arginine in combination with picolinic acid, which is effective at a pH of about 10.
    Type: Application
    Filed: November 22, 2006
    Publication date: May 22, 2008
    Applicants: Clarkson University, Infotonics Technology Center Inc.
    Inventors: Suryadevara V. Babu, Anita Natarajan
  • Publication number: 20080119051
    Abstract: A method of removing polysilicon in preference to silicon dioxide and/or silicon nitride by chemical mechanical polishing. The method removes polysilicon from a surface at a high removal rate while maintaining a high selectivity of polysilicon to silicon dioxide and/or a polysilicon to silicon nitride. The method is particularly suitable for use in the fabrication of MEMS devices.
    Type: Application
    Filed: November 22, 2006
    Publication date: May 22, 2008
    Applicants: Clarkson University, Infotonics Technology Center Inc.
    Inventors: Suryadevara V. Babu, Anita Natarajan, Sharath Hegde
  • Publication number: 20080116171
    Abstract: The present invention provides a method of removing silicon nitride in preference to silicon dioxide by CMP. The method utilizes a polishing slurry that includes colloidal silica abrasive particles dispersed in water and an additive that suppresses the silicon dioxide removal rate but enhances the silicon nitride removal rate. In one embodiment of the invention, the additive is lysine, which is effective at a pH of about 9, or arginine, which is effective at a pH of about 8. In another embodiment of the invention, the additive is lysine mono hydrochloride in combination with picolinic acid, which is effective at a pH of about 8, or arginine in combination with picolinic acid, which is effective at a pH of about 9.
    Type: Application
    Filed: November 22, 2006
    Publication date: May 22, 2008
    Applicants: Clarkson University, Infotonics Technology Center Inc.
    Inventors: Suryadevara V. Babu, Anita Natarajan
  • Patent number: 7279119
    Abstract: This invention relates to a silica, a slurry composition, and a method of their preparation. In particular, the silica of the present invention includes aggregated primary particles. The slurry composition which incorporates the silica, is suitable for polishing articles and especially useful for chemical-mechanical planarization of semiconductor substrates and other microelectronic substrates.
    Type: Grant
    Filed: July 28, 2003
    Date of Patent: October 9, 2007
    Assignee: PPG Industries Ohio, Inc.
    Inventors: Stuart D. Hellring, Colin P. McCann, Suryadevara V. Babu, Yuzhuo Li, Satish Narayanan, Robert L. Auger
  • Patent number: 7091164
    Abstract: A new slurry for shallow trench isolation (STI) processing in the chemical mechanical planarization (CMP) in microelectronic industry comprising an aqueous medium having an abrasive; and a compound which has a carboxylic group and an electrophilic functional group. The combination of ceria and/or titania with amino acids to obtain polishing selectivity's greater than 5:1. CMP is used for removing the excess oxide and planarizing the substrate and the trench. The silicon nitride acts as a stop layer, preventing the polishing of underlying silicon substrate.
    Type: Grant
    Filed: July 11, 2003
    Date of Patent: August 15, 2006
    Assignees: Eastman Kodak Company, Ferro Corporation, Clarkson University
    Inventors: Ramanathan Srinivasan, Suryadevara V. Babu, William G. America, Yie-Shein Her
  • Patent number: 6918820
    Abstract: This invention relates generally to compositions and methods for removing adherent materials and polishing surfaces. In one embodiment, the method employs an improved media comprising core-shell particles. The media can be applied to microelectronic objects of manufacture.
    Type: Grant
    Filed: April 11, 2003
    Date of Patent: July 19, 2005
    Assignee: Eastman Kodak Company
    Inventors: Dennis E. Smith, Suryadevara V. Babu
  • Publication number: 20040203324
    Abstract: This invention relates generally to compositions and methods for removing adherent materials and polishing surfaces. In one embodiment, the method employs an improved media comprising core-shell particles. The media can be applied to microelectronic objects of manufacture.
    Type: Application
    Filed: April 11, 2003
    Publication date: October 14, 2004
    Inventors: Dennis E. Smith, Suryadevara V. Babu
  • Publication number: 20040127045
    Abstract: An aqueous composition for chemical mechanical planarization of a wafer or film using a fixed polishing pad, includes:
    Type: Application
    Filed: September 12, 2003
    Publication date: July 1, 2004
    Inventors: Venkata R. K. Gorantla, Suryadevara V. Babu
  • Publication number: 20040067649
    Abstract: This invention relates to a silica, a slurry composition, and a method of their preparation. In particular, the silica of the present invention includes aggregated primary particles. The slurry composition which incorporates the silica, is suitable for polishing articles and especially useful for chemical-mechanical planarization of semiconductor substrates and other microelectronic substrates.
    Type: Application
    Filed: July 28, 2003
    Publication date: April 8, 2004
    Inventors: Stuart D. Hellring, Colin P. McCann, Suryadevara V. Babu, Yuzhuo Li, Satish Narayanan, Robert L. Auger
  • Publication number: 20040051077
    Abstract: A new slurry for shallow trench isolation (STI) processing in the chemical mechanical planarization (CMP) in microelectronic industry comprising an aqueous medium having an abrasive; and a compound which has a carboxylic group and an electrophilic functional group. The combination of ceria and/or titania with amino acids to obtain polishing selectivity's greater than 5:1. CMP is used for removing the excess oxide and planarizing the substrate and the trench. The silicon nitride acts as a stop layer, preventing the polishing of underlying silicon substrate.
    Type: Application
    Filed: July 11, 2003
    Publication date: March 18, 2004
    Inventors: Ramanathan Srinivasan, Suryadevara V. Babu, William G. America, Yie-Shein Her