Patents by Inventor Manjul Bhushan

Manjul Bhushan 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: 20060273803
    Abstract: A method and apparatus is provided for measuring alternating current (AC) and direct current (DC) characteristics of a plurality of semiconductor devices. A ring oscillator generates pulses to drive the plurality of semiconductor devices under test. Current/Voltage (IV) and transfer characteristics of the plurality of semiconductor devices are measured using only DC input/output.
    Type: Application
    Filed: June 29, 2006
    Publication date: December 7, 2006
    Applicant: International Business Machines Corporation
    Inventors: Manjul Bhushan, Mark Ketchen
  • Patent number: 7145347
    Abstract: A method and apparatus for measuring alternating current (AC) and direct current (DC) characteristics of a plurality of semiconductor devices. A ring oscillator generates pulses to drive the plurality of semiconductor devices under test. Current/Voltage (IV) and transfer characteristics of the plurality of semiconductor devices are measured using only DC input/output.
    Type: Grant
    Filed: August 31, 2004
    Date of Patent: December 5, 2006
    Assignee: International Business Machines Corporation
    Inventors: Manjul Bhushan, Mark B. Ketchen
  • Patent number: 7085658
    Abstract: A method and apparatus for monitoring a plurality of semiconductor devices is disclosed. At least one array of 2n semiconductor circuits is provided. A clock ring oscillator provides a clock signal. The clock signal drives a frequency divider followed by an n-stage binary counter. The outputs from the counter's stages drive an n-input decoder which sequentially addresses each semiconductor circuit. An output signal from each semiconductor circuit is measured and read out over a common bus, where a distribution of the output signals is a measure of a distribution of a parameter of interest.
    Type: Grant
    Filed: October 20, 2004
    Date of Patent: August 1, 2006
    Assignee: International Business Machines Corporation
    Inventors: Manjul Bhushan, Mark B. Ketchen
  • Publication number: 20060158239
    Abstract: An integrated circuit device having at least one fuse capable of being blown in order to provide measurements of fuse current-voltage characteristics is provided. The integrated circuit device also provides at least one pulse generation circuit associated with the fuse and capable of generating a pulse to blow the fuse through one or more DC input signals.
    Type: Application
    Filed: January 18, 2005
    Publication date: July 20, 2006
    Applicant: International Business Machines Corporation
    Inventors: Manjul Bhushan, Mark Ketchen, Chandrasekharan Kothandaraman, Edward Maciejewski
  • Patent number: 7069525
    Abstract: A set of ring oscillators is formed within a predetermined distance of each other. Each ring oscillator includes a number of coupled stages. The stages for a first given ring oscillator include an inverter having one or more first MOS devices having a first gate length. The stages for a second given ring oscillator include one or more second MOS devices having a second designed gate length. The stages for a third given ring oscillator comprise one or more third MOS devices having a third designed gate length. The second and third designed gate lengths are different and one of the second and third designed gate lengths is approximately equal to the first designed gate length. Performance is measured by using one of more of the given ring oscillators. The set of ring oscillators is used to determine one or more additional characteristics of MOS devices in the ring oscillators.
    Type: Grant
    Filed: July 18, 2003
    Date of Patent: June 27, 2006
    Assignee: International Business Machines Corporation
    Inventors: Manjul Bhushan, Mark B. Ketchen
  • Publication number: 20060100811
    Abstract: A method and apparatus for monitoring a plurality of semiconductor devices is disclosed. At least one array of 2n semiconductor circuits is provided. A clock ring oscillator provides a clock signal. The clock signal drives a frequency divider followed by an n-stage binary counter. The outputs from the counter's stages drive an n-input decoder which sequentially addresses each semiconductor circuit. An output signal from each semiconductor circuit is measured and read out over a common bus, where a distribution of the output signals is a measure of a distribution of a parameter of interest.
    Type: Application
    Filed: October 20, 2004
    Publication date: May 11, 2006
    Inventors: Manjul Bhushan, Mark Ketchen
  • Publication number: 20060044004
    Abstract: A method and apparatus for measuring alternating current (AC) and direct current (DC) characteristics of a plurality of semiconductor devices. A ring oscillator generates pulses to drive the plurality of semiconductor devices under test. Current/Voltage (IV) and transfer characteristics of the plurality of semiconductor devices are measured using only DC input/output.
    Type: Application
    Filed: August 31, 2004
    Publication date: March 2, 2006
    Inventors: Manjul Bhushan, Mark Ketchen
  • Patent number: 6960926
    Abstract: A method of characterizing a circuit comprises the steps of measuring a first delay associated with the circuit when the circuit is substantially unloaded; measuring a second delay associated with the circuit when the circuit is loaded by a predetermined impedance; determining a difference between the second delay and the first delay, the delay difference corresponding to a switching impedance associated with the circuit; and determining a characterization parameter of the circuit, the characterization parameter being a function of at least the switching impedance associated with the circuit. The methodologies of the present invention are directed primarily to individually evaluating pullup and pulldown delays with substantial precision (e.g., sub-picosecond) for a representative set of circuits in the presence of an arbitrary switching history.
    Type: Grant
    Filed: June 24, 2002
    Date of Patent: November 1, 2005
    Assignee: International Business Machines Corporation
    Inventors: Carl J. Anderson, Manjul Bhushan, Mark B. Ketchen
  • Publication number: 20050012556
    Abstract: A set of ring oscillators is formed within a predetermined distance of each other. Each ring oscillator includes a number of coupled stages. The stages for a first given ring oscillator include an inverter having one or more first MOS devices having a first gate length. The stages for a second given ring oscillator include an inverter substantially identical to the inverters in the coupled stages of the first given ring oscillator and one or more second MOS devices having a second designed gate length. The stages for a third given ring oscillator comprise an inverter substantially identical to the inverters in the coupled stages of the first given ring oscillator and one or more third MOS devices having a third designed gate length. The second and third designed gate lengths are different and one of the second and third designed gate lengths is approximately equal to the first designed gate length. Performance is measured by using one of more of the given ring oscillators.
    Type: Application
    Filed: July 18, 2003
    Publication date: January 20, 2005
    Applicant: International Business Machines Corporation
    Inventors: Manjul Bhushan, Mark Ketchen
  • Patent number: 6798261
    Abstract: A method for characterizing a change in delay induced by a switching history of a circuit includes the steps of generating a first signal having a pulse width that is selectively adjustable, the first signal having a first edge and a second edge associated therewith, the first and second edges being opposite in polarity with respect to one another; generating a second signal having a first switch delay characteristic of the first edge of the first signal and a second switch delay characteristic of the second edge of the first signal, wherein the pulse width of the first signal is less than the first switch delay associated with the second signal; varying the pulse width of the first signal; monitoring the second signal; determining a value of the pulse width that defines a boundary of when the second signal is present and when the second signal is not present; and determining a ratio of the value of the pulse width that defines the boundary to the first switch delay and/or the second switch delay, whereby the
    Type: Grant
    Filed: May 22, 2003
    Date of Patent: September 28, 2004
    Assignee: International Business Machines Corporation
    Inventors: Manjul Bhushan, Mark B. Ketchen, Dale J. Pearson
  • Publication number: 20030237029
    Abstract: A method of characterizing a circuit comprises the steps of measuring a first delay associated with the circuit when the circuit is substantially unloaded; measuring a second delay associated with the circuit when the circuit is loaded by a predetermined impedance; determining a difference between the second delay and the first delay, the delay difference corresponding to a switching impedance associated with the circuit; and determining a characterization parameter of the circuit, the characterization parameter being a function of at least the switching impedance associated with the circuit. The methodologies of the present invention are directed primarily to individually evaluating pullup and pulldown delays with substantial precision (e.g., sub-picosecond) for a representative set of circuits in the presence of an arbitrary switching history.
    Type: Application
    Filed: June 24, 2002
    Publication date: December 25, 2003
    Applicants: International Business, Machines Corporation
    Inventors: Carl J. Anderson, Manjul Bhushan, Mark B. Ketchen
  • Patent number: 4443653
    Abstract: A thin film photovoltaic device which utilizes at least one compound semiconductor layer chosen from Groups IIB and VA of the Periodic Table is formed on a multilayer substrate The substrate includes a lowermost support layer on which all of the other layers of the device are formed. Additionally, an uppermost carbide or silicon layer is adjacent to the semiconductor layer. Below the carbide or silicon layer is a metal layer of high conductivity and expansion coefficient equal to or slightly greater than that of the semiconductor layer.
    Type: Grant
    Filed: February 23, 1982
    Date of Patent: April 17, 1984
    Assignee: The University of Delaware
    Inventors: Anthony W. Catalano, Manjul Bhushan
  • Patent number: 4342879
    Abstract: A thin film photovoltaic solar cell which utilizes a zinc phosphide semiconductor is of the homojunction type comprising an n-type conductivity region forming an electrical junction with a p-type region, both regions consisting essentially of the same semiconductor material. The n-type region is formed by treating zinc phosphide with an extrinsic dopant such as magnesium. The semiconductor is formed on a multilayer substrate which acts as an opaque contact. Various transparent contacts may be used, including a thin metal film of the same chemical composition as the n-type dopant or conductive oxides or metal grids.
    Type: Grant
    Filed: October 24, 1980
    Date of Patent: August 3, 1982
    Assignee: The University of Delaware
    Inventors: Anthony W. Catalano, Manjul Bhushan