Patents by Inventor Chandrasekharan Kothandaraman

Chandrasekharan Kothandaraman 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: 8159040
    Abstract: A semiconductor structure and a method for fabricating the semiconductor structure provide a field effect device located and formed upon an active region of a semiconductor substrate and at least one of a fuse structure, an anti-fuse structure and a resistor structure located and formed at least in part simultaneously upon an isolation region laterally separated from the active region within the semiconductor substrate. The field effect device includes a gate dielectric comprising a high dielectric constant dielectric material and a gate electrode comprising a metal material. The at least one of the fuse structure, anti-fuse structure and resistor structure includes a pad dielectric comprising the same material as the gate dielectric, and optionally, also a fuse, anti-fuse or resistor that may comprise the same metal material as the gate electrode.
    Type: Grant
    Filed: May 13, 2008
    Date of Patent: April 17, 2012
    Assignee: International Business Machines Corporation
    Inventors: Douglas D. Coolbaugh, Ebenezer E. Eshun, Ephrem G. Gebreselasie, Zhong-Xiang He, Herbert Lei Ho, Deok-kee Kim, Chandrasekharan Kothandaraman, Dan Moy, Robert Mark Rassel, John Matthew Safran, Kenneth Jay Stein, Norman Whitelaw Robson, Ping-Chuan Wang, Hongwen Yan
  • Publication number: 20120012977
    Abstract: An antifuse is provided having a unitary monocrystalline semiconductor body including first and second semiconductor regions each having the same first conductivity type, and a third semiconductor region between the first and second semiconductor regions which has a second conductivity type opposite from the first conductivity type. An anode and a cathode can be electrically connected with the first semiconductor region. A conductive region including a metal, a conductive compound of a metal or an alloy of a metal can contact the first semiconductor region and extend between the cathode and the anode. The antifuse can further include a contact electrically connected with the second semiconductor region.
    Type: Application
    Filed: July 14, 2010
    Publication date: January 19, 2012
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Yan Zun Li, Chandrasekharan Kothandaraman, Dan Moy, Norman W. Robson, John M. Safran
  • Publication number: 20110272779
    Abstract: An eFuse, includes: a substrate and an insulating layer disposed on the substrate; a first layer including a single crystal or polycrystalline silicon disposed on the insulating layer; a second layer including a single crystal or polycrystalline silicon germanium disposed on the first layer, and a third layer including a silicide disposed on the second layer. The Ge has a final concentration in a range of approximately five percent to approximately twenty-five percent.
    Type: Application
    Filed: July 22, 2011
    Publication date: November 10, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Deok-Kee Kim, Dureseti Chidambarrao, William K. Henson, Chandrasekharan Kothandaraman
  • Patent number: 8030736
    Abstract: A method forms an anti-fuse structure comprises a plurality of parallel conductive fins positioned on a substrate, each of the fins has a first end and a second end. A second electrical conductor is electrically connected to the second end of the fins. An insulator covers the first end of the fins and a first electrical conductor is positioned on the insulator. The first electrical conductor is electrically insulated from the first end of the fins by the insulator. The insulator is formed to a thickness sufficient to break down on the application of a predetermined voltage between the second electrical conductor and the first electrical conductor and thereby form an uninterrupted electrical connection between the second electrical conductor and the first electrical conductor through the fins.
    Type: Grant
    Filed: August 10, 2009
    Date of Patent: October 4, 2011
    Assignee: International Business Machines Corporation
    Inventors: Roger A. Booth, Jr., Kangguo Cheng, Chandrasekharan Kothandaraman
  • Publication number: 20110207286
    Abstract: A reversible fuse structure in an integrated circuit is obtained through the implementation of a fuse cell having a short thin line of phase change materials in contact with via and line structures capable of passing current through the line of phase change material (fuse cell). The current is passed through the fuse cell in order to change the material from a less resistive material to a more resistive material through heating the phase change material in the crystalline state to the melting point then quickly quenching the material into the amorphous state. The reversible programming is achieved by passing a lower current through the fuse cell to convert the high resistivity amorphous material to a lower resistivity crystalline material. Appropriate sense-circuitry is integrated to read the information stored in the fuses, wherein said sense circuitry is used to enable or disable circuitry.
    Type: Application
    Filed: May 4, 2011
    Publication date: August 25, 2011
    Inventors: Geoffrey W. Burr, Chandrasekharan Kothandaraman, Chung Hon Lam, Xiao Hu Liu, Stephen M. Rossnagel, Christy S. Tyberg, Robert L. Wisnieff
  • Patent number: 8004060
    Abstract: A metal layer and a semiconductor layer are sequentially deposited on a substrate. The semiconductor layer and the metal layer are lithographically patterned to form a stack of a semiconductor portion and a metal gate portion, which is preferably performed concurrently with formation of at least one metal gate stack. In one embodiment, the size of the semiconductor portion is reduced and a metal semiconductor alloy portion is formed on the semiconductor portion by metallization. In a first electrical antifuse formed thereby, the metal semiconductor alloy portion may be electromigrated to form a short between the metal semiconductor alloy portion and the metal gate portion. In another embodiment, two disjoined metal semiconductor alloy portions are formed on the semiconductor portion. In a second electrical antifuse formed thereby, the metal semiconductor alloy portion may be electromigrated to form a short between the two previously disjoined metal semiconductor alloy portions.
    Type: Grant
    Filed: November 29, 2007
    Date of Patent: August 23, 2011
    Assignee: International Business Machines Corporation
    Inventors: Deok-kee Kim, Chandrasekharan Kothandaraman, Dan Moy, Norman W. Robson, John M. Safran, Kenneth J. Stein
  • Patent number: 8004059
    Abstract: An eFuse, includes: a substrate and an insulating layer disposed on the substrate; a first layer including a single crystal or polycrystalline silicon disposed on the insulating layer; a second layer including a single crystal or polycrystalline silicon germanium disposed on the first layer, and a third layer including a silicide disposed on the second layer. The Ge has a final concentration in a range of approximately five percent to approximately twenty-five percent.
    Type: Grant
    Filed: January 12, 2007
    Date of Patent: August 23, 2011
    Assignee: International Business Machines Corporation
    Inventors: Deok-Kee Kim, Dureseti Chidambarrao, William K. Henson, Chandrasekharan Kothandaraman
  • Publication number: 20110187407
    Abstract: Embodiments of the invention provides a method, device, and system for programming an electromigration fuse (eFuse) using a radio frequency (RF) signal. A first aspect of the invention provides a method of testing circuitry on a semiconductor chip, the method comprising: receiving a radio frequency (RF) signal using at least one antenna on the semiconductor chip; powering circuitry on the semiconductor chip using the RF signal; activating a built-in self test (BIST) engine within the circuitry; determining whether a fault exists within the circuitry using the BIST; and programming an electromigration fuse (eFuse) to alter the circuitry in response to a fault being determined to exist.
    Type: Application
    Filed: January 29, 2010
    Publication date: August 4, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Subramanian S. Iyer, Chandrasekharan Kothandaraman, Gerard M. Salem
  • Patent number: 7982285
    Abstract: The present invention provides antifuse structures having an integrated heating element and methods of programming the same, the antifuse structures comprising first and second conductors and a dielectric layer formed between the conductors, where one or both of the conductors functions as both a conventional antifuse conductor and as a heating element for directly heating the antifuse dielectric layer during programming.
    Type: Grant
    Filed: January 8, 2008
    Date of Patent: July 19, 2011
    Assignee: International Business Machines Corporation
    Inventors: Byeongju Park, Subramanian S. Iyer, Chandrasekharan Kothandaraman
  • Patent number: 7960808
    Abstract: A reversible fuse structure in an integrated circuit is obtained through the implementation of a fuse cell having a short thin line of phase change materials in contact with via and line structures capable of passing current through the line of phase change material (fuse cell). The current is passed through the fuse cell in order to change the material from a less resistive material to a more resistive material through heating the phase change material in the crystalline state to the melting point then quickly quenching the material into the amorphous state. The reversible programming is achieved by passing a lower current through the fuse cell to convert the high resistivity amorphous material to a lower resistivity crystalline material. Appropriate sense-circuitry is integrated to read the information stored in the fuses, wherein said sense circuitry is used to enable or disable circuitry.
    Type: Grant
    Filed: August 23, 2007
    Date of Patent: June 14, 2011
    Assignee: International Business Machines Corporation
    Inventors: Geoffrey W. Burr, Chandrasekharan Kothandaraman, Chung Hon Lam, Xiao Hu Liu, Stephen M. Rossnagel, Christy S. Tyberg, Robert L. Wisnieff
  • Patent number: 7960809
    Abstract: A fuse includes a fuse link region, a first region and a second region. The fuse link region electrically connects the first region to the second region. A SiGe layer is disposed only in the fuse link region and the first region.
    Type: Grant
    Filed: January 16, 2009
    Date of Patent: June 14, 2011
    Assignee: International Business Machines Corporation
    Inventors: Chandrasekharan Kothandaraman, Deok-kee Kim, Dureseti Chidambarrao, William K. Henson
  • Patent number: 7943493
    Abstract: A contiguous block of a stack of two heterogeneous semiconductor layers is formed over an insulator region such as shallow trench isolation. A portion of the contiguous block is exposed to an etch, while another portion is masked during the etch. The etch removes an upper semiconductor layer selective to a lower semiconductor layer in the exposed portion. The etch mask is removed and the entirety of the lower semiconductor layer within the exposed region is metallized. A first metal semiconductor alloy vertically abutting the insulator region is formed, while exposed surfaces of the stack of two heterogeneous semiconductor layers, which comprises the materials of the upper semiconductor layer, are concurrently metallized to form a second metal semiconductor alloy. An inflection point for current and, consequently, a region of flux divergence are formed at the boundary of the two metal semiconductor alloys.
    Type: Grant
    Filed: September 1, 2010
    Date of Patent: May 17, 2011
    Assignee: International Business Machines Corporation
    Inventors: Dureseti Chidambarrao, William K. Henson, Deok-Kee Kim, Chandrasekharan Kothandaraman
  • Publication number: 20110101496
    Abstract: The present invention provides antifuse structures having an integrated heating element and methods of programming the same, the antifuse structures comprising first and second conductors and a dielectric layer formed between the conductors, where one or both of the conductors functions as both a conventional antifuse conductor and as a heating element for directly heating the antifuse dielectric layer during programming.
    Type: Application
    Filed: January 11, 2011
    Publication date: May 5, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Byeongju Park, Subramanian S. Iyer, Chandrasekharan Kothandaraman
  • Publication number: 20110049460
    Abstract: A method of fabricating a phase change memory element within a semiconductor structure includes etching an opening to an upper surface of a bottom electrode, the opening being formed of a height equal to a height of a metal region at a same layer within the semiconductor structure, depositing phase change material within the opening, recessing the phase change material within the opening, and forming a top electrode on the recessed phase change material.
    Type: Application
    Filed: August 28, 2009
    Publication date: March 3, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Matthew J. Breitwisch, Chandrasekharan Kothandaraman, Chung H. Lam
  • Publication number: 20110031582
    Abstract: A method forms an anti-fuse structure comprises a plurality of parallel conductive fins positioned on a substrate, each of the fins has a first end and a second end. A second electrical conductor is electrically connected to the second end of the fins. An insulator covers the first end of the fins and a first electrical conductor is positioned on the insulator. The first electrical conductor is electrically insulated from the first end of the fins by the insulator. The insulator is formed to a thickness sufficient to break down on the application of a predetermined voltage between the second electrical conductor and the first electrical conductor and thereby form an uninterrupted electrical connection between the second electrical conductor and the first electrical conductor through the fins.
    Type: Application
    Filed: August 10, 2009
    Publication date: February 10, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Roger A. Booth, JR., Kangguo Cheng, Chandrasekharan Kothandaraman
  • Patent number: 7880266
    Abstract: The present invention provides antifuse structures having an integrated heating element and methods of programming the same, the antifuse structures comprising first and second conductors and a dielectric layer formed between the conductors, where one or both of the conductors functions as both a conventional antifuse conductor and as a heating element for directly heating the antifuse dielectric layer during programming.
    Type: Grant
    Filed: December 3, 2007
    Date of Patent: February 1, 2011
    Assignee: International Business Machines Corporation
    Inventors: Byeongju Park, Subramanian S. Iyer, Chandrasekharan Kothandaraman
  • Publication number: 20100330783
    Abstract: A contiguous block of a stack of two heterogeneous semiconductor layers is formed over an insulator region such as shallow trench isolation. A portion of the contiguous block is exposed to an etch, while another portion is masked during the etch. The etch removes an upper semiconductor layer selective to a lower semiconductor layer in the exposed portion. The etch mask is removed and the entirety of the lower semiconductor layer within the exposed region is metallized. A first metal semiconductor alloy vertically abutting the insulator region is formed, while exposed surfaces of the stack of two heterogeneous semiconductor layers, which comprises the materials of the upper semiconductor layer, are concurrently metallized to form a second metal semiconductor alloy. An inflection point for current and, consequently, a region of flux divergence are formed at the boundary of the two metal semiconductor alloys.
    Type: Application
    Filed: September 1, 2010
    Publication date: December 30, 2010
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Dureseti Chidambarrao, William K. Henson, Deok-Kee Kim, Chandrasekharan Kothandaraman
  • Publication number: 20100327399
    Abstract: An electrically programmable fuse that includes an anode contact region and a cathode contact region are formed of a polysilicon layer having a silicide layer formed thereon, and a fuse link conductively connecting the cathode contact region with the anode contact region, which is programmable by applying a programming current, and a plurality of anisometric contacts formed on the silicide layer of the cathode contact region or on both the silicide layer of the cathode contact region and the anode contact region in a predetermined configuration, respectively.
    Type: Application
    Filed: June 29, 2009
    Publication date: December 30, 2010
    Applicant: International Business Machines Corporation
    Inventors: CHANDRASEKHARAN KOTHANDARAMAN, DAN MOY, NORMAN W. ROBSON, JOHN M. SAFRAN
  • Patent number: 7838963
    Abstract: A contiguous block of a stack of two heterogeneous semiconductor layers is formed over an insulator region such as shallow trench isolation. A portion of the contiguous block is exposed to an etch, while another portion is masked during the etch. The etch removes an upper semiconductor layer selective to a lower semiconductor layer in the exposed portion. The etch mask is removed and the entirety of the lower semiconductor layer within the exposed region is metallized. A first metal semiconductor alloy vertically abutting the insulator region is formed, while exposed surfaces of the stack of two heterogeneous semiconductor layers, which comprises the materials of the upper semiconductor layer, are concurrently metallized to form a second metal semiconductor alloy. An inflection point for current and, consequently, a region of flux divergence are formed at the boundary of the two metal semiconductor alloys.
    Type: Grant
    Filed: October 26, 2007
    Date of Patent: November 23, 2010
    Assignee: International Business Machines Corporation
    Inventors: Dureseti Chidambarrao, William K. Henson, Deok-Kee Kim, Chandrasekharan Kothandaraman
  • Patent number: 7825479
    Abstract: An electrical antifuse comprising a field effect transistor includes a gate dielectric having two gate dielectric portions. Upon application of electric field across the gate dielectric, the magnitude of the electrical field is locally enhanced at the boundary between the thick and thin gate dielectric portions due to the geometry, thereby allowing programming of the electrical antifuse at a lower supply voltage between the two electrodes, i.e., the body and the gate electrode of the transistor, across the gate dielectric.
    Type: Grant
    Filed: August 6, 2008
    Date of Patent: November 2, 2010
    Assignee: International Business Machines Corporation
    Inventors: Roger A. Booth, Jr., Kangguo Cheng, Chandrasekharan Kothandaraman, Chengwen Pei, Ravi M. Todi, Xiaojun Yu