Patents by Inventor Mahadevaiyer Krishnan

Mahadevaiyer Krishnan 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).

  • Publication number: 20120083125
    Abstract: Planarization methods include depositing a mask material on top of an overburden layer on a semiconductor wafer. The mask material is planarized to remove the mask material from up areas of the overburden layer to expose the overburden layer without removing the mask material from down areas. The exposed overburden layer is wet etched and leaves a thickness remaining over an underlying layer. Remaining portions of the mask layer and the exposed portions of the overburden layer are planarized to expose the underlying layer.
    Type: Application
    Filed: January 25, 2011
    Publication date: April 5, 2012
    Applicants: JSR CORPORATION, INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Leslie Charns, John M. Cotte, Jason E. Cummings, Lukasz J. Hupka, Dinesh R. Koli, Tomohisa Konno, Mahadevaiyer Krishnan, Michael F. Lafaro, Jakub W. Nalaskowski, Masahiro Noda, Dinesh K. Penigalapati, Tatsuya Yamanaka
  • Publication number: 20120040277
    Abstract: A reticle carrier for a polishing tool capable of accommodating a reticle includes a base plate with an obverse and reverse surfaces, a retaining ring secured to the obverse surface of the base plate forming a recess defined by the obverse surface of the rigid base plate and internal edges of the retaining ring. A reticle pad supports a reticle in the recess. The base plate and the reticle pad having an array of matching, aligned passageway holes therethrough for exhaustion of air from space between the base plate and a the reticle and for supply of air to that space so a vacuum can retain a the reticle in place on the reticle carrier under vacuum conditions and application of air under pressure can eject a reticle from the reticle carrier.
    Type: Application
    Filed: October 21, 2011
    Publication date: February 16, 2012
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Kevin S. Petrarca, Donald F. Canaperi, Mahadevaiyer Krishnan, Rebecca D. Mih, Steven Steen, Henry Grabarz, Michael S. Hibbs
  • Patent number: 8110321
    Abstract: A method for manufacturing an optical projection reticle employs a damascene process. First feature recesses are etched into a projection reticle mask plate which is transmissive or transparent. Then feature recesses are tilled with a radiation transmissivity modifying material comprising a partially transmissive material and/or a radiation absorber for absorbing actinic radiation. Sacrificial materials may be added to the recess temporarily prior to filling the recess to provide gaps juxtaposed with the material filling the recess. Thereafter, the sacrificial materials are removed. Then the projection mask is planarized leaving feature recesses filled with transmissivity modifying material, and any gaps desired. The projection mask is planarized while retained in a fixture holding it in place during polishing with a polishing tool and a slurry.
    Type: Grant
    Filed: May 16, 2007
    Date of Patent: February 7, 2012
    Assignee: International Business Machines Corporation
    Inventors: Kevin S. Petrarca, Donald F. Canaperi, Mahadevaiyer Krishnan, Rebecca D. Mih, Steven Steen, Henry Grabarz, Michael S. Hibbs
  • Patent number: 8101518
    Abstract: The present invention provides a method for forming a self-aligned Ni alloy silicide contact. The method of the present invention begins by first depositing a conductive Ni alloy with Pt and optionally at least one of the following metals Pd, Rh, Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, W or Re over an entire semiconductor structure which includes at least one gate stack region. An oxygen diffusion barrier comprising, for example, Ti, TiN or W is deposited over the structure to prevent oxidation of the metals. An annealing step is then employed to cause formation of a NiSi, PtSi contact in regions in which the metals are in contact with silicon. The metal that is in direct contact with insulating material such as SiO2 and Si3N4 is not converted into a metal alloy silicide contact during the annealing step A. selective etching step is then performed to remove unreacted metal from the sidewalls of the spacers and trench isolation regions.
    Type: Grant
    Filed: June 11, 2008
    Date of Patent: January 24, 2012
    Assignee: International Business Machines Corporation
    Inventors: Cyril Cabral, Jr., Michael A. Cobb, Asa Frye, Balasubramanian S. Pranatharthi Haran, Randolph F. Knarr, Mahadevaiyer Krishnan, Christian Lavoie, Andrew P. Mansson, Renee T. Mo, Jay W. Strane, Horatio S. Wildman
  • Publication number: 20120009771
    Abstract: A method for formation of a segregated interfacial dopant layer at a junction between a semiconductor material and a silicide layer includes depositing a doped metal layer over the semiconductor material; annealing the doped metal layer and the semiconductor material, wherein the anneal causes a portion of the doped metal layer and a portion of the semiconductor material to react to form the silicide layer on the semiconductor material, and wherein the anneal further causes the segregated interfacial dopant layer to form between the semiconductor material and the silicide layer, the segregated interfacial dopant layer comprising dopants from the doped metal layer; and removing an unreacted portion of the doped metal layer from the silicide layer.
    Type: Application
    Filed: July 9, 2010
    Publication date: January 12, 2012
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Cyril Cabral, JR., John M. Cotte, Dinesh R. Koli, Laura L. Kosbar, Mahadevaiyer Krishnan, Christian Lavoie, Stephen M. Rossnagel, Zhen Zhang
  • Patent number: 8039382
    Abstract: The present invention relates to a method for forming self-aligned metal silicide contacts over at least two silicon-containing semiconductor regions that are spaced apart from each other by an exposed dielectric region. Preferably, each of the self-aligned metal silicide contacts so formed comprises at least nickel silicide and platinum silicide with a substantially smooth surface, and the exposed dielectric region is essentially free of metal and metal silicide. More preferably, the method comprises the steps of nickel or nickel alloy deposition, low-temperature annealing, nickel etching, high-temperature annealing, and aqua regia etching.
    Type: Grant
    Filed: August 12, 2009
    Date of Patent: October 18, 2011
    Assignee: International Business Machines Corporation
    Inventors: Sunfei Fang, Randolph F. Knarr, Mahadevaiyer Krishnan, Christian Lavoie, Renee T. Mo, Balasubramanian Pranatharthiharan, Jay W. Strane
  • Publication number: 20100051474
    Abstract: Methods and compositions for electro-chemical-mechanical polishing (e-CMP) of silicon chip interconnect materials, such as copper, are provided. The methods include the use of compositions according to the invention in combination with pads having various configurations.
    Type: Application
    Filed: August 27, 2009
    Publication date: March 4, 2010
    Inventors: Panayotis C. Andricacos, Caliopi Andricacos, Donald F. Canaperi, Emanuel I. Cooper, John M. Cotte, Hariklia Deligianni, Laertis Economikos, Daniel C. Edelstein, Silvia Franz, Balasubramanian Pranatharthiharan, Mahadevaiyer Krishnan, Andrew P. Mansson, Erick G. Walton, Alan C. West
  • Publication number: 20090309228
    Abstract: The present invention relates to a method for forming self-aligned metal silicide contacts over at least two silicon-containing semiconductor regions that are spaced apart from each other by an exposed dielectric region. Preferably, each of the self-aligned metal silicide contacts so formed comprises at least nickel silicide and platinum silicide with a substantially smooth surface, and the exposed dielectric region is essentially free of metal and metal silicide. More preferably, the method comprises the steps of nickel or nickel alloy deposition, low-temperature annealing, nickel etching, high-temperature annealing, and aqua regia etching.
    Type: Application
    Filed: August 12, 2009
    Publication date: December 17, 2009
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Sunfei Fang, Randolph F. Knarr, Mahadevaiyer Krishnan, Christian Lavoie, Renee T. Mo, Balasubramanian Pranatharthiharan, Jay W. Strane
  • Patent number: 7618891
    Abstract: The present invention relates to a method for forming self-aligned metal silicide contacts over at least two silicon-containing semiconductor regions that are spaced apart from each other by an exposed dielectric region. Preferably, each of the self-aligned metal silicide contacts so formed comprises at least nickel silicide and platinum silicide with a substantially smooth surface, and the exposed dielectric region is essentially free of metal and metal silicide. More preferably, the method comprises the steps of nickel or nickel alloy deposition, low-temperature annealing, nickel etching, high-temperature annealing, and aqua regia etching.
    Type: Grant
    Filed: May 1, 2006
    Date of Patent: November 17, 2009
    Assignee: International Business Machines Corporation
    Inventors: Sunfei Fang, Randolph F. Knarr, Mahadevaiyer Krishnan, Christian Lavoie, Renee T. Mo, Balasubramanian Pranatharthiharan, Jay W. Strane
  • Patent number: 7581314
    Abstract: A semiconductor micro-electromechanical system (MEMS) switch provided with noble metal contacts that act as an oxygen barrier to copper electrodes is described. The MEMS switch is fully integrated into a CMOS semiconductor fabrication line. The integration techniques, materials and processes are fully compatible with copper chip metallization processes and are typically, a low cost and a low temperature process (below 400° C.). The MEMS switch includes: a movable beam within a cavity, the movable beam being anchored to a wall of the cavity at one or both ends of the beam; a first electrode embedded in the movable beam; and a second electrode embedded in an wall of the cavity and facing the first electrode, wherein the first and second electrodes are respectively capped by the noble metal contact.
    Type: Grant
    Filed: February 21, 2006
    Date of Patent: September 1, 2009
    Assignee: International Business Machines Corporation
    Inventors: Hariklia Deligianni, Panayotis Andricacos, L. Paivikki Buchwalter, John M. Cotte, Christopher Jahnes, Mahadevaiyer Krishnan, John H. Magerlein, Kenneth Stein, Richard P. Volant, James A. Tornello, Jennifer Lund
  • Patent number: 7544610
    Abstract: The present invention provides a method for forming a self-aligned Ni alloy silicide contact. The method of the present invention begins by first depositing a conductive Ni alloy with Pt and optionally at least one of the following metals Pd, Rh, Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, W or Re over an entire semiconductor structure which includes at least one gate stack region. An oxygen diffusion barrier comprising, for example, Ti, TiN or W is deposited over the structure to prevent oxidation of the metals. An annealing step is then employed to cause formation of a NiSi, PtSi contact in regions in which the metals are in contact with silicon. The metal that is in direct contact with insulating material such as SiO2 and Si3N4 is not converted into a metal alloy silicide contact during the annealing step. A selective etching step is then performed to remove unreacted metal from the sidewalls of the spacers and trench isolation regions.
    Type: Grant
    Filed: September 7, 2004
    Date of Patent: June 9, 2009
    Assignee: International Business Machines Corporation
    Inventors: Cyril Cabral, Jr., Michael A. Cobb, Asa Frye, Balasubramanian S. Pranatharthi Haran, Randolph F. Knarr, Mahadevaiyer Krishnan, Christian Lavoie, Andrew P. Mansson, Renee T. Mo, Jay W. Strane, Horatio S. Wildman
  • Publication number: 20090127711
    Abstract: A highly reliable copper interconnect structure and method of fabricating the same is provided. The interconnect structure comprises a metal layer buried between an adjacent upper copper layer and an adjacent lower copper layer structure. More specifically, the interconnect structure comprises a recess formed in a dielectric layer; a barrier metal lining sidewalls of the recess; a first copper layer within the recess; a second copper layer within the recess; and a metal layer buried between the first copper layer and the second copper layer. The method comprises forming a recess in an interlayer dielectric; forming a first copper layer, a metal layer over the first copper layer and a second copper layer over the metal layer, all within the recess. The metal layer is sandwiched between the first copper layer and the second copper layer within the recess.
    Type: Application
    Filed: November 15, 2007
    Publication date: May 21, 2009
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Griselda Bonilla, Daniel C. Edelstein, Mahadevaiyer Krishnan, Takeshi Nogami, David L. Rath
  • Publication number: 20080286660
    Abstract: A method for manufacturing an optical projection reticle employs a damascene process. First feature recesses are etched into a projection reticle mask plate which is transmissive or transparent. Then feature recesses are tilled with a radiation transmissivity modifying material comprising a partially transmissive material and/or a radiation absorber for absorbing actinic radiation. Sacrificial materials may be added to the recess temporarily prior to filling the recess to provide gaps juxtaposed with the material filling the recess. Thereafter, the sacrificial materials are removed. Then the projection mask is planarized leaving feature recesses filled with transmissivity modifying material, and any gaps desired. The projection mask is planarized while retained in a fixture holding it in place during polishing with a polishing tool and a slurry.
    Type: Application
    Filed: May 16, 2007
    Publication date: November 20, 2008
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Kevin S. Petrarca, Donald F. Canaperi, Mahadevaiyer Krishnan, Rebecca D. Mih, Steven Steen, Henry Grabarz, Michael S. Hibbs
  • Publication number: 20080274611
    Abstract: The present invention provides a method for forming a self-aligned Ni alloy silicide contact. The method of the present invention begins by first depositing a conductive Ni alloy with Pt and optionally at least one of the following metals Pd, Rh, Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, W or Re over an entire semiconductor structure which includes at least one gate stack region. An oxygen diffusion barrier comprising, for example, Ti, TiN or W is deposited over the structure to prevent oxidation of the metals. An annealing step is then employed to cause formation of a NiSi, PtSi contact in regions in which the metals are in contact with silicon. The metal that is in direct contact with insulating material such as SiO2 and Si3N4 is not converted into a metal alloy silicide contact during the annealing step A selective etching step is then performed to remove unreacted metal from the sidewalls of the spacers and trench isolation regions.
    Type: Application
    Filed: June 11, 2008
    Publication date: November 6, 2008
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Cyril Cabral, Michael A. Cobb, Asa Frye, Balasubramanian S. Pranatharthi Haran, Randolph F. Knarr, Mahadevaiyer Krishnan, Christian Lavoie, Andrew P. Mansson, Renee T. Mo, Jay W. Strane, Horatio S. Wildman
  • Patent number: 7407605
    Abstract: An aqueous seeding solution of palladium acetate, acetic acid and chloride.
    Type: Grant
    Filed: May 22, 2007
    Date of Patent: August 5, 2008
    Assignee: International Business Machines Corporation
    Inventors: Darryl D. Restaino, Donald F. Canaperi, Judith M. Rubino, Sean P. E. Smith, Richard O. Henry, James E. Fluegel, Mahadevaiyer Krishnan
  • Publication number: 20080156636
    Abstract: Defects on the edge of copper interconnects for back end of the line semiconductor devices are alleviated by an interconnect that comprises an impure copper seed layer. The impure copper seed layer covers a barrier layer, which covers an insulating layer that has an opening. Electroplated copper fills the opening in the insulating layer. Through a chemical mechanical polish, the barrier layer, the impure an impure copper seed layer derived from an electroplated copper bath copper seed layer, and the electroplated copper are planarized to the insulating layer.
    Type: Application
    Filed: January 9, 2008
    Publication date: July 3, 2008
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Kevin S. Petrarca, Mahadevaiyer Krishnan, Michael Lofaro, Kenneth P. Rodbell
  • Publication number: 20070254479
    Abstract: The present invention relates to a method for forming self-aligned metal silicide contacts over at least two silicon-containing semiconductor regions that are spaced apart from each other by an exposed dielectric region. Preferably, each of the self-aligned metal silicide contacts so formed comprises at least nickel silicide and platinum silicide with a substantially smooth surface, and the exposed dielectric region is essentially free of metal and metal silicide. More preferably, the method comprises the steps of nickel or nickel alloy deposition, low-temperature annealing, nickel etching, high-temperature annealing, and aqua regia etching.
    Type: Application
    Filed: May 1, 2006
    Publication date: November 1, 2007
    Applicant: International Business Machines Corporation
    Inventors: Sunfei Fang, Randolph Knarr, Mahadevaiyer Krishnan, Christian Lavoie, Renee Mo, Balasubramanian Pranatharthiharan, Jay Strane
  • Publication number: 20070215842
    Abstract: An aqueous seeding solution of palladium acetate, acetic acid and chloride.
    Type: Application
    Filed: May 22, 2007
    Publication date: September 20, 2007
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Darryl Restaino, Donald Canaperi, Judith Rubino, Sean Smith, Richard Henry, James Fluegel, Mahadevaiyer Krishnan
  • Patent number: 7253106
    Abstract: A method to electrolessly plate a CoWP alloy on copper in a reproducible manner that is effective for a manufacturable process. In the method, a seed layer of palladium (Pd) is deposited on the copper by an aqueous seeding solution of palladium acetate, acetic acid and chloride. Thereafter, a complexing solution is applied to remove any Pd ions which are adsorbed on surfaces other than the copper. Finally, a plating solution of cobalt (Co), tungsten (W) and phosphorous (P) is applied to the copper so as to deposit a layer of CoWP on the Pd seed and copper.
    Type: Grant
    Filed: December 22, 2004
    Date of Patent: August 7, 2007
    Assignee: International Business Machines Corporation
    Inventors: Darryl D. Restaino, Donald F. Canaperi, Judith M. Rubino, Sean P. E. Smith, Richard O. Henry, James E. Fluegel, Mahadevaiyer Krishnan
  • Patent number: 7202764
    Abstract: A semiconductor micro-electromechanical system (MEMS) switch provided with noble metal contacts that act as an oxygen barrier to copper electrodes is described. The MEMS switch is fully integrated into a CMOS semiconductor fabrication line. The integration techniques, materials and processes are fully compatible with copper chip metallization processes and are typically, a low cost and a low temperature process (below 400° C.). The MEMS switch includes: a movable beam within a cavity, the movable beam being anchored to a wall of the cavity at one or both ends of the beam; a first electrode embedded in the movable beam; and a second electrode embedded in an wall of the cavity and facing the first electrode, wherein the first and second electrodes are respectively capped by the noble metal contact.
    Type: Grant
    Filed: July 8, 2003
    Date of Patent: April 10, 2007
    Assignee: International Business Machines Corporation
    Inventors: Hariklia Deligianni, Panayotis Andricacos, L. Paivikki Buchwalter, John M. Cotte, Christopher Jahnes, Mahadevaiyer Krishnan, John H. Magerlein, Kenneth Stein, Richard P. Volant, James A. Tornello, Jennifer Lund