Patents by Inventor Madhavi R. Chandrachood

Madhavi R. Chandrachood 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: 11249386
    Abstract: Extreme ultraviolet (EUV) mask blanks, methods for their manufacture and production systems therefor are disclosed. The EUV mask blanks comprise a substrate having a first side and a second side; a backside coating layer comprising an alloy of tantalum and nickel on the first side of the substrate; a multilayer stack of reflective layers on the second side of the substrate, the multilayer stack of reflective layers including a plurality of reflective layers including reflective layer pairs; a capping layer on the multilayer stack of reflecting layers; and an absorber layer on the capping layer.
    Type: Grant
    Filed: October 24, 2019
    Date of Patent: February 15, 2022
    Assignee: APPLIED MATERIALS, INC.
    Inventors: Vibhu Jindal, Madhavi R Chandrachood, Vikash Banthia
  • Publication number: 20200133114
    Abstract: Extreme ultraviolet (EUV) mask blanks, methods for their manufacture and production systems therefor are disclosed. The EUV mask blanks comprise a substrate having a first side and a second side; a backside coating layer comprising an alloy of tantalum and nickel on the first side of the substrate; a multilayer stack of reflective layers on the second side of the substrate, the multilayer stack of reflective layers including a plurality of reflective layers including reflective layer pairs; a capping layer on the multilayer stack of reflecting layers; and an absorber layer on the capping layer.
    Type: Application
    Filed: October 24, 2019
    Publication date: April 30, 2020
    Inventors: Vibhu Jindal, Madhavi R. Chandrachood, Vikash Banthia
  • Patent number: 10170280
    Abstract: A plasma reactor has an array of plural gas injectors arranged around a circular side wall that are individually controlled.
    Type: Grant
    Filed: October 26, 2015
    Date of Patent: January 1, 2019
    Assignee: Applied Materials, Inc.
    Inventors: Madhavi R. Chandrachood, Michael N. Grimbergen, Khiem K. Nguyen, Richard Lewington, Ibrahim M. Ibrahim, Sheeba J. Panayil, Ajay Kumar
  • Publication number: 20160042917
    Abstract: A plasma reactor has an array of plural gas injectors arranged around a circular side wall that are individually controlled.
    Type: Application
    Filed: October 26, 2015
    Publication date: February 11, 2016
    Inventors: Madhavi R. Chandrachood, Michael N. Grimbergen, Khiem K. Nguyen, Richard Lewington, Ibrahim M. Ibrahim, Sheeba J. Panayil, Ajay Kumar
  • Patent number: 9218944
    Abstract: A plasma reactor has an array of passages extending through its workpiece support pedestal from a bottom thereof that forms a two-dimensional array of openings in the support surface. The reactor further includes a plurality of optical fibers, each fiber extending through a respective one of the passages. Optical sensing apparatus is coupled to the output ends of the optical fibers and is responsive in the range of wavelengths. The reactor further includes a tunable element capable of changing a two-dimensional etch rate distribution across the surface of a workpiece supported on the pedestal, and a process controller connected to receive information from the optical sensing apparatus and to transmit control commands to the tunable element.
    Type: Grant
    Filed: October 30, 2006
    Date of Patent: December 22, 2015
    Assignee: APPLIED MATERIALS, INC.
    Inventors: Madhavi R. Chandrachood, Michael N. Grimbergen, Khiem K. Nguyen, Richard Lewington, Ibrahim M. Ibrahim, Sheeba J. Panayil, Ajay Kumar
  • Patent number: 8568553
    Abstract: A method and apparatus for etching photomasks is provided herein. In one embodiment, the apparatus comprises a process chamber having a support pedestal adapted for receiving a photomask. An ion-neutral shield is disposed above the pedestal and a deflector plate assembly is provided above the ion-neutral shield. The deflector plate assembly defines a gas flow direction for process gases towards the ion-neutral shield, while the ion-neutral shield is used to establish a desired distribution of ion and neutral species in a plasma for etching the photomask.
    Type: Grant
    Filed: March 10, 2011
    Date of Patent: October 29, 2013
    Assignee: Applied Materials, Inc.
    Inventors: Ajay Kumar, Madhavi R. Chandrachood, Richard Lewington, Darin Bivens, Amitabh Sabharwal, Sheeba J. Panayil, Alan Hiroshi Ouye
  • Patent number: 8202441
    Abstract: Method and apparatus for etching a metal layer disposed on a substrate, such as a photolithographic reticle, are provided. In one aspect, a method is provided for processing a substrate including positioning a substrate having a metal layer disposed on an optically transparent material in a processing chamber, introducing a processing gas processing gas comprising an oxygen containing gas, a chlorine containing gas, and a chlorine-free halogen containing gas, and optionally, an inert gas, into the processing chamber, generating a plasma of the processing gas in the processing chamber, and etching exposed portions of the metal layer disposed on the substrate.
    Type: Grant
    Filed: March 22, 2010
    Date of Patent: June 19, 2012
    Assignee: Applied Materials, Inc.
    Inventors: Madhavi R. Chandrachood, Nicole Sandlin, Yung-Hee Yvette Lee, Jian Ding
  • Patent number: 8017029
    Abstract: A plasma etch method includes simultaneously illuminating an array of plural locations on front surface of the workpiece through the backside of the workpiece with light of a wavelength range for which the workpiece is transparent, while viewing light reflected from the array of plural locations to the backside of the workpiece. The method further includes determining plural etch depths at the array of locations from the light reflected from the array of locations on the front side of the workpiece, and deducing from the plural etch depths a spatial distribution of etch rate across the array of locations. The method also includes changing the etch rate distribution by adjusting a tunable element of the reactor.
    Type: Grant
    Filed: October 30, 2006
    Date of Patent: September 13, 2011
    Assignee: Applied Materials, Inc.
    Inventors: Madhavi R. Chandrachood, Michael N. Grimbergen, Khiem K. Nguyen, Richard Lewington, Ibrahim M. Ibrahim, Sheeba J. Panayil, Ajay Kumar
  • Patent number: 8012366
    Abstract: A method is provided for defining a pattern on a workpiece such as a transparent substrate or mask or a workpiece that is at least transparent within a range of optical wavelengths. The method includes defining a photoresist pattern on the top surface of the mask, the pattern including a periodic structure having a periodic spacing between elements of the structure. The method further includes placing the mask on a support pedestal in a plasma reactor chamber and generating a plasma in the chamber to etch the top surface of the mask through openings in the photoresist pattern. The method also includes transmitting light through the pedestal and through the bottom surface of the mask, while viewing through the support pedestal light reflected from the periodic structure and detecting an interference pattern in the reflected light. The method further includes determining from the interference pattern a depth to which periodic structure has been etched in the top surface.
    Type: Grant
    Filed: October 30, 2006
    Date of Patent: September 6, 2011
    Assignee: Applied Materials, Inc.
    Inventors: Richard Lewington, Michael N. Grimbergen, Khiem K. Nguyen, Darin Bivens, Madhavi R. Chandrachood, Ajay Kumar
  • Patent number: 8002946
    Abstract: A plasma reactor for etching a workpiece such as a rectangular or square mask, includes a vacuum chamber having a ceiling and a sidewall and a workpiece support pedestal within the chamber including a cathode having a surface for supporting a workpiece, the surface comprising plural respective zones, the respective zones of the surface being formed of respective materials of different electrical characteristics. The zones can be arranged concentrically relative to an axis of symmetry of the wafer support pedestal.
    Type: Grant
    Filed: October 30, 2006
    Date of Patent: August 23, 2011
    Assignee: Applied Materials, Inc.
    Inventors: Richard Lewington, Michael N. Grimbergen, Khiem K. Nguyen, Darin Bivens, Madhavi R. Chandrachood, Ajay Kumar
  • Patent number: 7976671
    Abstract: A plasma reactor for processing a workpiece such as a mask or wafer includes a vacuum chamber having a cylindrical side wall, a ceiling overlying the side wall and a ring supported on a top edge of the side wall and supporting the ceiling, the ring comprising an external surface and an interior surface. An RF plasma source power applicator and an RF source power generator coupled to the applicator furnish plasma source power. Plural passages extend in a radial direction through the ring from the external surface to the interior surface and are spaced apart along a circumference of the ring. A process gas supply furnishes process gas. An external gas flow conduit apparatus outside of the chamber extends around a circumference of the chamber and is coupled to the process gas supply.
    Type: Grant
    Filed: October 30, 2006
    Date of Patent: July 12, 2011
    Assignee: Applied Materials, Inc.
    Inventors: Madhavi R. Chandrachood, Michael N. Grimbergen, Khiem K. Nguyen, Richard Lewington, Ibrahim M. Ibrahim, Sheeba J. Panayil, Ajay Kumar
  • Publication number: 20110162797
    Abstract: A method and apparatus for etching photomasks is provided herein. In one embodiment, the apparatus comprises a process chamber having a support pedestal adapted for receiving a photomask. An ion-neutral shield is disposed above the pedestal and a deflector plate assembly is provided above the ion-neutral shield. The deflector plate assembly defines a gas flow direction for process gases towards the ion-neutral shield, while the ion-neutral shield is used to establish a desired distribution of ion and neutral species in a plasma for etching the photomask.
    Type: Application
    Filed: March 10, 2011
    Publication date: July 7, 2011
    Inventors: Ajay Kumar, Madhavi R. Chandrachood, Richard Lewington, Darin Bivens, Amitabh Sabharwal, Sheeba J. Panayil, Alan Hiroshi Ouye
  • Patent number: 7967930
    Abstract: A plasma reactor is provided for processing a workpiece such as a transparent mask or a semiconductor wafer. The reactor includes a vacuum chamber having a ceiling and a sidewall. A workpiece support pedestal within the chamber includes a metal cathode having a support surface facing the ceiling and defining a support plane for supporting a workpiece. The cathode has a hollow space formed within its interior. The reactor further includes a movable metal element within the hollow space and a mechanism for controlling a distance between the metal element and the support plane.
    Type: Grant
    Filed: October 30, 2006
    Date of Patent: June 28, 2011
    Assignee: Applied Materials, Inc.
    Inventors: Richard Lewington, Michael N. Grimbergen, Khiem K. Nguyen, Darin Bivens, Madhavi R. Chandrachood, Ajay Kumar
  • Patent number: 7964818
    Abstract: A method of fabricating yttria parts is provided herein. In one embodiment, the method includes sintering a yttria sample, machining the sintered sample to form a part, and annealing the part in a three-stage process that includes heating the part at a predetermined heating rate, maintaining the part at a constant annealing temperature, and cooling the part at a predetermined cooling rate.
    Type: Grant
    Filed: October 30, 2006
    Date of Patent: June 21, 2011
    Assignee: Applied Materials, Inc.
    Inventors: Elmira Ryabova, Richard Lewington, Madhavi R. Chandrachood, Amitabh Sabharwal, Darin Bivens
  • Patent number: 7955516
    Abstract: Methods for etching a metal layer using an imprinted resist material are provided. In one embodiment, a method for processing a photolithographic reticle includes providing a reticle having a metal photomask layer formed on an optically transparent substrate and an imprinted resist material deposited on the metal photomask layer, etching recessed regions of the imprinted resist material to expose portions of the metal photomask layer in a first etching step, and etching the exposed portions of the metal photomask layer through the imprinted resist material in a second etching step, wherein at least one of the first or second etching steps utilizes a plasma formed from a processing gas comprising oxygen, halogen and chlorine containing gases. In one embodiment, the process gas is utilized in both the first and second etching steps. In another embodiment, the first and second etching steps are performed in the same processing chamber.
    Type: Grant
    Filed: August 9, 2007
    Date of Patent: June 7, 2011
    Assignee: Applied Materials, Inc.
    Inventors: Madhavi R. Chandrachood, Ajay Kumar
  • Patent number: 7943005
    Abstract: A method and apparatus for etching photomasks is provided herein. In one embodiment, the apparatus comprises a process chamber having a support pedestal adapted for receiving a photomask. An ion-neutral shield is disposed above the pedestal and a deflector plate assembly is provided above the ion-neutral shield. The deflector plate assembly defines a gas flow direction for process gases towards the ion-neutral shield, while the ion-neutral shield is used to establish a desired distribution of ion and neutral species in a plasma for etching the photomask.
    Type: Grant
    Filed: October 30, 2006
    Date of Patent: May 17, 2011
    Assignee: Applied Materials, Inc.
    Inventors: Ajay Kumar, Madhavi R. Chandrachood, Richard Lewington, Darin Bivens, Amitabh Sabharwal, Sheeba J. Panayil, Alan Hiroshi Ouye
  • Patent number: 7909961
    Abstract: A method and apparatus for etching photomasks are provided herein. The apparatus includes a process chamber with a shield above a substrate support. The shield comprises a plate with apertures, and the plate has two zones with at least one characteristic, such as material or potential bias, that is different from each other. The method provides for etching a photomask substrate with a distribution of ions and neutral species that pass through the shield.
    Type: Grant
    Filed: October 30, 2006
    Date of Patent: March 22, 2011
    Assignee: Applied Materials, Inc.
    Inventors: Ajay Kumar, Madhavi R. Chandrachood, Richard Lewington, Darin Bivens, Amitabh Sabharwal, Sheeba J. Panayil, Alan Hiroshi Ouye
  • Publication number: 20100276391
    Abstract: Methods of operating inductively coupled plasma (ICP) reactors having ICP sources and substrate bias with phase control are provided herein. In some embodiments, a method of operating a first plasma reactor having a source RF generator inductively coupled to the first plasma reactor on one side of a substrate support surface of a substrate support within the first plasma reactor and a bias RF generator coupled to the substrate support on an opposing side of the substrate support surface, wherein the source RF generator and the bias RF generator provide respective RF signals at a common frequency may include selecting a desired value of a process parameter for a substrate to be processed; and adjusting the phase between respective RF signals provided by the source RF generator and the bias RF generator to a desired phase based upon a predetermined relationship between the process parameter and the phase.
    Type: Application
    Filed: March 29, 2010
    Publication date: November 4, 2010
    Applicant: APPLIED MATERIALS, INC.
    Inventors: MICHAEL N. GRIMBERGEN, KEVEN KAISHENG YU, ALAN HIROSHI OUYE, MADHAVI R. CHANDRACHOOD, VALENTIN N. TODOROW, TOI YUE BECKY LEUNG, RICHARD LEWINGTON, DARIN BIVENS, RENEE KOCH, IBRAHIM M. IBRAHIM, AMITABH SABHARWAL, AJAY KUMAR
  • Patent number: 7771895
    Abstract: Embodiments of methods of etching EUV photomasks are provided herein. In one embodiment, a method of etching an extreme ultraviolet photomask includes providing a photomask comprising, in order, a substrate, a multi-material layer, a capping layer, and a multi-layer absorber layer, the multilayer absorber layer comprising a self-mask layer disposed over a bulk absorber layer, wherein the self-mask layer comprises tantalum and oxygen and the bulk absorber layer comprises tantalum and essentially no oxygen; etching the self-mask layer using a first etch process; and etching the bulk absorber layer using a second etch process different than the first, wherein the etch rate of the bulk absorber layer is greater than the etch rate of the self-mask layer during the second etch process.
    Type: Grant
    Filed: September 15, 2006
    Date of Patent: August 10, 2010
    Assignee: Applied Materials, Inc.
    Inventors: Banqiu Wu, Madhavi R. Chandrachood, Ajay Kumar
  • Publication number: 20100178600
    Abstract: Method and apparatus for etching a metal layer disposed on a substrate, such as a photolithographic reticle, are provided. In one aspect, a method is provided for processing a substrate including positioning a substrate having a metal layer disposed on an optically transparent material in a processing chamber, introducing a processing gas processing gas comprising an oxygen containing gas, a chlorine containing gas, and a chlorine-free halogen containing gas, and optionally, an inert gas, into the processing chamber, generating a plasma of the processing gas in the processing chamber, and etching exposed portions of the metal layer disposed on the substrate.
    Type: Application
    Filed: March 22, 2010
    Publication date: July 15, 2010
    Applicant: APPLIED MATERIALS, INC.
    Inventors: Madhavi R. Chandrachood, Nicole Sandlin, Yung-Hee Yvette Lee, Jian Ding