Patents by Inventor Mandyam A. Sriram

Mandyam A. Sriram 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: 8524612
    Abstract: Embodiments related to depositing thin conformal films using plasma-activated conformal film deposition (CFD) processes are described herein. In one example, a method of processing a substrate includes, applying photoresist to the substrate, exposing the photoresist to light via a stepper, patterning the resist with a pattern and transferring the pattern to the substrate, selectively removing photoresist from the substrate, placing the substrate into a process station, and, in the process station, in a first phase, generating radicals off of the substrate and adsorbing the radicals to the substrate to form active species, in a first purge phase, purging the process station, in a second phase, supplying a reactive plasma to the surface, the reactive plasma configured to react with the active species and generate the film, and in a second purge phase, purging the process station.
    Type: Grant
    Filed: January 21, 2011
    Date of Patent: September 3, 2013
    Assignee: Novellus Systems, Inc.
    Inventors: Ming Li, Hu Kang, Mandyam Sriram, Adrien LaVoie
  • Patent number: 8479683
    Abstract: A method of forming a boron nitride or boron carbon nitride dielectric produces a conformal layer without loading effect. The dielectric layer is formed by chemical vapor deposition (CVD) of a boron-containing film on a substrate, at least a portion of the deposition being conducted without plasma, and then exposing the deposited boron-containing film to a plasma. The CVD component dominates the deposition process, producing a conformal film without loading effect. The dielectric is ashable, and can be removed with a hydrogen plasma without impacting surrounding materials. The dielectric has a much lower wet etch rate compared to other front end spacer or hard mask materials such as silicon oxide or silicon nitride, and has a relatively low dielectric constant, much lower then silicon nitride.
    Type: Grant
    Filed: September 13, 2012
    Date of Patent: July 9, 2013
    Assignee: Novellus Systems, Inc.
    Inventors: George Andrew Antonelli, Mandyam Sriram, Vishwanathan Rangarajan, Pramod Subramonium
  • Publication number: 20130157466
    Abstract: The embodiments herein relate to plasma-enhanced chemical vapor deposition methods and apparatus for depositing silicon nitride on a substrate. The disclosed methods provide silicon nitride films having wet etch rates (e.g., in dilute hydrofluoric acid or hot phosphoric acid) suitable for certain applications such as vertical memory devices. Further, the methods provide silicon nitride films having defined levels of internal stress suitable for the applications in question. These silicon nitride film characteristics can be set or tuned by controlling, for example, the composition and flow rates of the precursors, as well as the RF power supplied to the plasma and the pressure in the reactor. In certain embodiments, a boron-containing precursor is added.
    Type: Application
    Filed: February 13, 2013
    Publication date: June 20, 2013
    Inventors: Keith Fox, Dong Niu, Joseph L. Womack, Mandyam Sriram, George Andrew Antonelli, Bart J. van Schravendijk, Jennifer O'Loughlin
  • Publication number: 20130040447
    Abstract: Disclosed herein are methods of doping a patterned substrate in a reaction chamber. The methods may include forming a first conformal film layer which has a dopant source including a dopant, and driving some of the dopant into the substrate to form a conformal doping profile. In some embodiments, forming the first film layer may include introducing a dopant precursor into the reaction chamber, adsorbing the dopant precursor under conditions whereby it forms an adsorption-limited layer, and reacting the adsorbed dopant precursor to form the dopant source. Also disclosed herein are apparatuses for doping a substrate which may include a reaction chamber, a gas inlet, and a controller having machine readable code including instructions for operating the gas inlet to introduce dopant precursor into the reaction chamber so that it is adsorbed, and instructions for reacting the adsorbed dopant precursor to form a film layer containing a dopant source.
    Type: Application
    Filed: September 7, 2012
    Publication date: February 14, 2013
    Inventors: Shankar Swaminathan, Mandyam Sriram, Bart van Schravendijk, Pramod Subramonium, Adrien La Voie
  • Patent number: 8362571
    Abstract: Transistor architectures and fabrication processes generate channel strain without adversely impacting the efficiency of the transistor fabrication process while preserving the material quality and enhancing the performance of the resulting transistor. Transistor strain is generated is PMOS devices using a highly compressive post-salicide amorphous carbon capping layer applied as a blanket over on at least the source and drain regions. The stress from this capping layer is uniaxially transferred to the PMOS channel through the source-drain regions to create compressive strain in PMOS channel.
    Type: Grant
    Filed: January 28, 2011
    Date of Patent: January 29, 2013
    Assignee: Novellus Systems, Inc.
    Inventors: Qingguo Wu, James S. Sims, Mandyam Sriram, Seshasayee Varadarajan, Haiying Fu, Pramod Subramonium, Jon Henri, Sirish Reddy
  • Publication number: 20130008378
    Abstract: A method of forming a boron nitride or boron carbon nitride dielectric produces a conformal layer without loading effect. The dielectric layer is formed by chemical vapor deposition (CVD) of a boron-containing film on a substrate, at least a portion of the deposition being conducted without plasma, and then exposing the deposited boron-containing film to a plasma. The CVD component dominates the deposition process, producing a conformal film without loading effect. The dielectric is ashable, and can be removed with a hydrogen plasma without impacting surrounding materials. The dielectric has a much lower wet etch rate compared to other front end spacer or hard mask materials such as silicon oxide or silicon nitride, and has a relatively low dielectric constant, much lower then silicon nitride.
    Type: Application
    Filed: September 13, 2012
    Publication date: January 10, 2013
    Inventors: George Andrew Antonelli, Mandyam Sriram, Vishwanathan Rangarajan, Pramod Subramonium
  • Patent number: 8317923
    Abstract: Protective self aligned buffer (PSAB) layers are layers of material that are selectively formed at the surface of metal layers in a partially fabricated semiconductor device. In a Damascene interconnect, PSAB layer typically resides at an interface between the metal layer and a dielectric diffusion barrier layer. PSAB layers promote improved adhesion between a metal layer and an adjacent dielectric diffusion barrier layer. Further, PSAB layers can protect metal surfaces from inadvertent oxidation during fabrication process. A PSAB layer may be formed entirely within the top portion of a metal layer, by, for example, chemically converting metal surface to a thin layer of metal silicide. Thickness of PSAB layers, and, consequently resistance of interconnects can be controlled by partially passivating metal surface prior to formation of PSAB layer. Such passivation can be accomplished by controllably treating metal surface with a nitrogen-containing compound to convert metal to metal nitride.
    Type: Grant
    Filed: April 16, 2010
    Date of Patent: November 27, 2012
    Assignee: Novellus Systems, Inc.
    Inventors: Kaushik Chattopadhyay, Bart van Schravendijk, Yongsik Yu, Mandyam Sriram
  • Patent number: 8288292
    Abstract: A method of forming a boron nitride or boron carbon nitride dielectric produces a conformal layer without loading effect. The dielectric layer is formed by chemical vapor deposition (CVD) of a boron-containing film on a substrate, at least a portion of the deposition being conducted without plasma, and then exposing the deposited boron-containing film to a plasma. The CVD component dominates the deposition process, producing a conformal film without loading effect. The dielectric is ashable, and can be removed with a hydrogen plasma without impacting surrounding materials. The dielectric has a much lower wet etch rate compared to other front end spacer or hard mask materials such as silicon oxide or silicon nitride, and has a relatively low dielectric constant, much lower than silicon nitride.
    Type: Grant
    Filed: March 30, 2010
    Date of Patent: October 16, 2012
    Assignee: Novellus Systems, Inc.
    Inventors: George Andrew Antonelli, Mandyam Sriram, Vishwanathan Rangarajan, Pramod Subramonium
  • Patent number: 8217513
    Abstract: Embodiments related to the cleaning of interface surfaces in a semiconductor wafer fabrication process via remote plasma processing are disclosed herein. For example, in one disclosed embodiment, a semiconductor processing apparatus includes a processing chamber, a load lock coupled to the processing chamber via a transfer port, a wafer pedestal disposed in the load lock and configured to support a wafer in the load lock, a remote plasma source configured to provide a remote plasma to the load lock, and an ion filter disposed between the remote plasma source and the wafer pedestal.
    Type: Grant
    Filed: February 2, 2011
    Date of Patent: July 10, 2012
    Assignee: Novellus Systems, Inc.
    Inventors: George Andrew Antonelli, Jennifer O'Loughlin, Tony Xavier, Mandyam Sriram, Bart van Schravendijk, Vishwanathan Rangarajan, Seshasayee Varadarajan, Bryan L. Buckalew
  • Publication number: 20120142172
    Abstract: Smooth silicon and silicon germanium films are deposited by plasma enhanced chemical vapor deposition (PECVD). The films are characterized by roughness (Ra) of less than about 4 ?. In some embodiments, smooth silicon films are undoped and doped polycrystalline silicon films. The dopants can include boron, phosphorus, and arsenic. In some embodiments the smooth polycrystalline silicon films are also highly conductive. For example, boron-doped polycrystalline silicon films having resistivity of less than about 0.015 Ohm cm and Ra of less than about 4 ? can be deposited by PECVD. In some embodiments smooth silicon films are incorporated into stacks of alternating layers of doped and undoped polysilicon, or into stacks of alternating layers of silicon oxide and doped polysilicon employed in memory devices. Smooth films can be deposited using a process gas having a low concentration of silicon-containing precursor and/or a process gas comprising a silicon-containing precursor and H2.
    Type: Application
    Filed: December 7, 2011
    Publication date: June 7, 2012
    Inventors: Keith FOX, Mandyam SRIRAM, Bart VAN SCHRAVENDIJK, Jennifer O'LOUGHLIN, Joe WOMACK
  • Publication number: 20120077349
    Abstract: Embodiments related to depositing thin conformal films using plasma-activated conformal film deposition (CFD) processes are described herein. In one example, a method of processing a substrate includes, applying photoresist to the substrate, exposing the photoresist to light via a stepper, patterning the resist with a pattern and transferring the pattern to the substrate, selectively removing photoresist from the substrate, placing the substrate into a process station, and, in the process station, in a first phase, generating radicals off of the substrate and adsorbing the radicals to the substrate to form active species, in a first purge phase, purging the process station, in a second phase, supplying a reactive plasma to the surface, the reactive plasma configured to react with the active species and generate the film, and in a second purge phase, purging the process station.
    Type: Application
    Filed: January 21, 2011
    Publication date: March 29, 2012
    Inventors: Ming Li, Hu Kang, Mandyam Sriram, Adrien LaVoie
  • Publication number: 20120028454
    Abstract: Methods of depositing a film on a substrate surface include surface mediated reactions in which a film is grown over one or more cycles of reactant adsorption and reaction. In one aspect, the method is characterized by intermittent delivery of dopant species to the film between the cycles of adsorption and reaction.
    Type: Application
    Filed: September 23, 2011
    Publication date: February 2, 2012
    Inventors: Shankar Swaminathan, Jon Henri, Dennis M. Hausmann, Pramod Subramonium, Mandyam Sriram, Vishwanathan Rangarajan, Kirthi K. Kattige, Bart J. van Schravendijk, Andrew J. McKerrow
  • Patent number: 8101531
    Abstract: Methods and hardware for depositing thin conformal films using plasma-activated conformal film deposition (CFD) processes are described herein. In one example, a method for forming a thin conformal film comprises, in a first phase, generating precursor radicals off of a surface of the substrate and adsorbing the precursor radicals to the surface to form surface active species; in a first purge phase, purging residual precursor from the process station; in a second phase, supplying a reactive plasma to the surface, the reactive plasma configured to react with the surface active species and generate the thin conformal film; and in a second purge phase, purging residual reactant from the process station.
    Type: Grant
    Filed: September 23, 2010
    Date of Patent: January 24, 2012
    Assignee: Novellus Systems, Inc.
    Inventors: Ming Li, Hu Kang, Mandyam Sriram, Adrien LaVoie
  • Publication number: 20120009802
    Abstract: Methods of depositing a film on a substrate surface include surface mediated reactions in which a film is grown over one or more cycles of reactant adsorption and reaction. In one aspect, the method is characterized by intermittent delivery of dopant species to the film between the cycles of adsorption and reaction.
    Type: Application
    Filed: September 1, 2011
    Publication date: January 12, 2012
    Inventors: Adrien LaVoie, Mandyam Sriram
  • Patent number: 8084339
    Abstract: Embodiments related to the cleaning of interface surfaces in a semiconductor wafer fabrication process via remote plasma processing are disclosed herein. For example, in one disclosed embodiment, a semiconductor processing apparatus includes a processing chamber, a load lock coupled to the processing chamber via a transfer port, a wafer pedestal disposed in the load lock and configured to support a wafer in the load lock, a remote plasma source configured to provide a remote plasma to the load lock, and an ion filter disposed between the remote plasma source and the wafer pedestal.
    Type: Grant
    Filed: June 12, 2009
    Date of Patent: December 27, 2011
    Assignee: Novellus Systems, Inc.
    Inventors: George Andrew Antonelli, Jennifer O'Loughlin, Tony Xavier, Mandyam Sriram, Bart Van Schravendijk, Vishwanathan Rangarajan, Seshasayee Varadarajan, Bryan L. Buckalew
  • Publication number: 20110256734
    Abstract: Described are methods of making SiN materials on substrates, particularly SiN thin films on semiconductor substrates. Improved SiN films made by the methods are also included.
    Type: Application
    Filed: April 11, 2011
    Publication date: October 20, 2011
    Inventors: Dennis M. Hausmann, Jon Henri, Mandyam Sriram, Bart J. van Schravendijk
  • Publication number: 20110256726
    Abstract: Methods of depositing a film on a substrate surface include surface mediated reactions in which a film is grown over one or more cycles of reactant adsorption and reaction. In one aspect, the method is characterized by the following operations: (a) exposing the substrate surface to a first reactant in vapor phase under conditions allowing the first reactant to adsorb onto the substrate surface; (b) exposing the substrate surface to a second reactant in vapor phase while the first reactant is adsorbed on the substrate surface; and (c) exposing the substrate surface to plasma to drive a reaction between the first and second reactants adsorbed on the substrate surface to form the film.
    Type: Application
    Filed: April 11, 2011
    Publication date: October 20, 2011
    Inventors: Adrien LaVoie, Shankar Swaminathan, Hu Kang, Ramesh Chandrasekharan, Tom Dorsh, Dennis M. Hausmann, Jon Henri, Thomas Jewell, Ming Li, Bryan Schlief, Antonio Xavier, Thomas W. Mountsier, Bart J. van Schravendijk, Easwar Srinivasan, Mandyam Sriram
  • Publication number: 20110244694
    Abstract: A method of forming a boron nitride or boron carbon nitride dielectric produces a conformal layer without loading effect. The dielectric layer is formed by chemical vapor deposition (CVD) of a boron-containing film on a substrate, at least a portion of the deposition being conducted without plasma, and then exposing the deposited boron-containing film to a plasma. The CVD component dominates the deposition process, producing a conformal film without loading effect. The dielectric is ashable, and can be removed with a hydrogen plasma without impacting surrounding materials. The dielectric has a much lower wet etch rate compared to other front end spacer or hard mask materials such as silicon oxide or silicon nitride, and has a relatively low dielectric constant, much lower then silicon nitride.
    Type: Application
    Filed: March 30, 2010
    Publication date: October 6, 2011
    Inventors: George Andrew Antonelli, Mandyam Sriram, Vishwanathan Rangarajan, Pramod Subramonium
  • Publication number: 20110236594
    Abstract: Methods and hardware for depositing film stacks in a process tool in-situ (i.e., without a vacuum break or air exposure) are described. In one example, a method for depositing, on a substrate, a film stack including films of different compositions in-situ in a process station using a plasma is described, the method including, in a first plasma-activated film deposition phase, depositing a first layer of film having a first film composition on the substrate; in a second plasma-activated deposition phase, depositing a second layer of film having a second film composition on the first layer of film; and sustaining the plasma while transitioning a composition of the plasma from the first plasma-activated film deposition phase to the second plasma-activated film deposition phase.
    Type: Application
    Filed: December 16, 2010
    Publication date: September 29, 2011
    Inventors: Jason Haverkamp, Pramod Subramonium, Joe Womack, Dong Niu, Keith Fox, John Alexy, Patrick Breiling, Jennifer O'Loughlin, Mandyam Sriram, George Andrew Antonelli, Bart van Schravendijk
  • Publication number: 20110236600
    Abstract: Methods and hardware for depositing ultra-smooth silicon-containing films and film stacks are described. In one example, an embodiment of a method for forming a silicon-containing film on a substrate in a plasma-enhanced chemical vapor deposition apparatus is disclosed, the method including supplying a silicon-containing reactant to the plasma-enhanced chemical vapor deposition apparatus; supplying a co-reactant to the plasma-enhanced chemical vapor deposition apparatus; supplying a capacitively-coupled plasma to a process station of the plasma-enhanced chemical vapor deposition apparatus, the plasma including silicon radicals generated from the silicon-containing reactant and co-reactant radicals generated from the co-reactant; and depositing the silicon-containing film on the substrate, the silicon-containing film having a refractive index of between 1.4 and 2.1, the silicon-containing film further having an absolute roughness of less than or equal to 4.5 ? as measured on a silicon substrate.
    Type: Application
    Filed: December 16, 2010
    Publication date: September 29, 2011
    Inventors: Keith Fox, Dong Niu, Joe Womack, Mandyam Sriram, George Andrew Antonelli, Bart van Schravendijk, Jennifer O'Loughlin