Patents by Inventor Chandrasekara Kothandaraman

Chandrasekara 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).

  • Publication number: 20180017509
    Abstract: Methods and systems for generating an identifier include detecting emissions from a phosphor pattern with a sensor grid comprising one or more sensors when the phosphor pattern is stimulated with radiation. An output signal of each sensor in the sensor grid is compared to a threshold value to generate respective identifier bits. An identifier is generated from the identifier bits.
    Type: Application
    Filed: July 18, 2016
    Publication date: January 18, 2018
    Inventors: Dirk Pfeiffer, Sami Rosenblatt, Chandrasekara Kothandaraman
  • Publication number: 20180019881
    Abstract: Methods and systems for generating an identifier includes testing an operational characteristic for each device in an array of pairs of devices. Each pair of devices includes a first device and a second device. The first device of each pair has a higher inter-device uniformity for the operational characteristic than the second device of the pair. The operational characteristic between the first device and the second device is compared for each pair of devices to generate a respective identifier bit for each pair of devices. An identifier is generated from the identifier bits.
    Type: Application
    Filed: July 13, 2016
    Publication date: January 18, 2018
    Inventors: Dirk Pfeiffer, Sami Rosenblatt, Chandrasekara Kothandaraman
  • Publication number: 20170356811
    Abstract: A ring oscillator system for characterizing substrate strain including, a substrate including a through-substrate-via, at least two ring oscillators, wherein a first ring oscillator is closer to the through-substrate-via than a second ring oscillator, and a logic difference circuit that is configured to receive an input from at least the first ring oscillator and the second ring oscillator, and detect a difference between the signal frequency of the first ring oscillator and the signal frequency of the second ring oscillator.
    Type: Application
    Filed: June 14, 2016
    Publication date: December 14, 2017
    Inventors: Chandrasekara Kothandaraman, Sami Rosenblatt, Akil K. Sutton
  • Patent number: 9698339
    Abstract: Embodiments are directed to an electromagnetic memory device having a memory cell and an encapsulation layer formed over the memory cell. The memory cell may include a magnetic tunnel junction (MTJ), and the encapsulation layer may be formed from a layer of hydrogenated amorphous silicon. Amorphous silicon improves the coercivity of the MTJ but by itself is conductive. Adding hydrogen to amorphous silicon passivates dangling bonds of the amorphous silicon, thereby reducing the ability of the resulting hydrogenated amorphous silicon layer to provide a parasitic current path to the MTJ. The hydrogenated amorphous silicon layer may be formed using a plasma-enhanced chemical vapor deposition, which can be tuned to enable a hydrogen level of approximately 10 to approximately 20 percent. By keeping subsequent processing operations at or below about 400 Celsius, the resulting layer of hydrogenated amorphous silicon can maintain its hydrogen level of approximately 10 to 20 percent.
    Type: Grant
    Filed: December 29, 2015
    Date of Patent: July 4, 2017
    Assignees: INTERNATIONAL BUSINESS MACHINES CORPORATION, SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Anthony J. Annunziata, Marinus Hopstaken, Chandrasekara Kothandaraman, JungHyuk Lee, Deborah A. Neumayer, Jeong-Heon Park
  • Publication number: 20170186943
    Abstract: Embodiments are directed to an electromagnetic memory device having a memory cell and an encapsulation layer formed over the memory cell. The memory cell may include a magnetic tunnel junction (MTJ), and the encapsulation layer may be formed from a layer of hydrogenated amorphous silicon. Amorphous silicon improves the coercivity of the MTJ but by itself is conductive. Adding hydrogen to amorphous silicon passivates dangling bonds of the amorphous silicon, thereby reducing the ability of the resulting hydrogenated amorphous silicon layer to provide a parasitic current path to the MTJ. The hydrogenated amorphous silicon layer may be formed using a plasma-enhanced chemical vapor deposition, which can be tuned to enable a hydrogen level of approximately 10 to approximately 20 percent. By keeping subsequent processing operations at or below about 400 Celsius, the resulting layer of hydrogenated amorphous silicon can maintain its hydrogen level of approximately 10 to 20 percent.
    Type: Application
    Filed: December 29, 2015
    Publication date: June 29, 2017
    Inventors: Anthony J. Annunziata, Marinus Hopstaken, Chandrasekara Kothandaraman, JungHyuk Lee, Deborah A. Neumayer, Jeong-Heon Park
  • Patent number: 9281390
    Abstract: A method of fabricating a memory device is provided that may begin with forming a layered gate stack atop a semiconductor substrate and patterning a metal electrode layer stopping on the high-k gate dielectric layer of the layered gate stack to provide a first metal gate electrode and a second metal gate electrode on the semiconductor substrate. In a next process sequence, at least one spacer is formed on the first metal gate electrode atop a portion of the high-k gate dielectric layer, wherein a remaining portion of the high-k gate dielectric is exposed. The remaining portion of the high-k gate dielectric layer is etched to provide a first high-k gate dielectric having a portion that extends beyond a sidewall of the first metal gate electrode and a second high-k gate dielectric having an edge that is aligned to a sidewall of the second metal gate electrode.
    Type: Grant
    Filed: August 12, 2013
    Date of Patent: March 8, 2016
    Assignee: GLOBALFOUNDRIES INC.
    Inventors: Roger A. Booth, Jr., Kangguo Cheng, Chandrasekara Kothandaraman, Chengwen Pei
  • Publication number: 20130328136
    Abstract: A method of fabricating a memory device is provided that may begin with forming a layered gate stack atop a semiconductor substrate and patterning a metal electrode layer stopping on the high-k gate dielectric layer of the layered gate stack to provide a first metal gate electrode and a second metal gate electrode on the semiconductor substrate. In a next process sequence, at least one spacer is formed on the first metal gate electrode atop a portion of the high-k gate dielectric layer, wherein a remaining portion of the high-k gate dielectric is exposed. The remaining portion of the high-k gate dielectric layer is etched to provide a first high-k gate dielectric having a portion that extends beyond a sidewall of the first metal gate electrode and a second high-k gate dielectric having an edge that is aligned to a sidewall of the second metal gate electrode.
    Type: Application
    Filed: August 12, 2013
    Publication date: December 12, 2013
    Applicant: International Business Machines Corporation
    Inventors: Roger A. Booth, JR., Kangguo Cheng, Chandrasekara Kothandaraman, Chengwen Pei
  • Patent number: 7551470
    Abstract: The embodiments of the invention provide an apparatus, method, etc. for a non volatile memory RAD-hard (NVM-rh) system. More specifically, an IC permanent non-volatile storage element comprises an integrated semiconductor stable reference component, wherein the component is resistant to external radiation. The storage element further comprises e-fuse structures in the component and a sensing circuit coupled to the e-fuse structures. The sensing circuit is adapted to update an external device at a specified time interval to reduce incidence of soft errors and errors due to power failure. Moreover, the sensing circuit is adapted to cease updating the external device to program the e-fuse structures; and, continue updating the external device after programming the e-fuse structures.
    Type: Grant
    Filed: October 19, 2006
    Date of Patent: June 23, 2009
    Assignee: International Business Machines Corporation
    Inventors: Karl R. Erickson, John A. Fifield, Chandrasekara Kothandaraman, Phil C. Paone, William R. Tonti
  • Publication number: 20080217733
    Abstract: The present invention provides an electrical fuse structure for achieving a post-programming resistance distribution with higher resistance values and to enhance the reliability of electrical fuse programming. A partly doped electrical fuse structure with undoped semiconductor material in the cathode combined with P-doped semiconductor material in the fuselink and anode is disclosed and the data supporting the superior performance of the disclosed electrical fuse is shown.
    Type: Application
    Filed: March 7, 2007
    Publication date: September 11, 2008
    Applicant: Inernational Business Machines Corporation
    Inventors: Subramanian S. Iyer, Deok-Kee Kim, Chandrasekara Kothandaraman, Byeongju Park
  • Publication number: 20080094896
    Abstract: The embodiments of the invention provide an apparatus, method, etc. for a non volatile memory RAD-hard (NVM-rh) system. More specifically, an IC permanent non-volatile storage element comprises an integrated semiconductor stable reference component, wherein the component is resistant to external radiation. The storage element further comprises e-fuse structures in the component and a sensing circuit coupled to the e-fuse structures. The sensing circuit is adapted to update an external device at a specified time interval to reduce incidence of soft errors and errors due to power failure. Moreover, the sensing circuit is adapted to cease updating the external device to program the e-fuse structures; and, continue updating the external device after programming the e-fuse structures.
    Type: Application
    Filed: October 19, 2006
    Publication date: April 24, 2008
    Inventors: Karl R. Erickson, John A. Fifield, Chandrasekara Kothandaraman, Phil C. Paone, William R. Tonti
  • Patent number: 6972614
    Abstract: An identification circuit for establishing and sensing the state of a fusible element used in on chip identification of the chip's type comprising: a circuit establishing control signals for turning the identification circuit on and off; dual paths energized by the control signals generated by the level setting circuit to energize one path through the fusible element to provide a state level and the other path through a reference path which provides a reference voltage level which is distinguishable from both the blown and unblown states of the fusible element; a differential sensing circuit for comparing the reference voltage level to the state level to provide a signal indicating the state of the fusible element; and protection circuitry to protect the circuit during an operation in which the state of the fusible element is set.
    Type: Grant
    Filed: April 7, 2004
    Date of Patent: December 6, 2005
    Assignee: International Business Machines Corporation
    Inventors: Mark E. Anderson, II, Sundar K. Iyer, Chandrasekara Kothandaraman, Edward P. Maciejewski, George E. Smith, III
  • Publication number: 20050225375
    Abstract: An identification circuit for establishing and sensing the state of a fusible element used in on chip identification of the chip's type comprising: a circuit establishing control signals for turning the identification circuit on and off; dual paths energized by the control signals generated by the level setting circuit to energize one path through the fusible element to provide a state level and the other path through a reference path which provides a reference voltage level which is distinguishable from both the blown and unblown states of the fusible element; a differential sensing circuit for comparing the reference voltage level to the state level to provide a signal indicating the state of the fusible element; and protection circuitry to protect the circuit during an operation in which the state of the fusible element is set.
    Type: Application
    Filed: April 7, 2004
    Publication date: October 13, 2005
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Mark Anderson, Sundar Iyer, Chandrasekara Kothandaraman, Edward Maciejewski, George Smith