Patents by Inventor Kenneth Wilsher

Kenneth Wilsher 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: 7659981
    Abstract: A system for probing a DUT is disclosed, the system having a pulsed laser source, a CW laser source, beam optics designed to point a reference beam and a probing beam at the same location on the DUT, optical detectors for detecting the reflected reference and probing beams, and a collection electronics. The beam optics is a common-path polarization differential probing (PDP) optics. The common-path PDP optics divides the incident laser beam into two beams of orthogonal polarization—one beam simulating a reference beam while the other simulating a probing beam. Both reference and probing beams are pointed to the same location on the DUT. Due to the intrinsic asymmetry of a CMOS transistor, the interaction of the reference and probing beams with the DUT result in different phase modulation in each beam. This difference can be investigated to study the response of the DUT to the stimulus signal.
    Type: Grant
    Filed: October 27, 2005
    Date of Patent: February 9, 2010
    Assignee: DCG Systems, Inc.
    Inventors: William Lo, Kenneth Wilsher, Nagamani Nataraj, Nina Boiadjieva
  • Patent number: 7616312
    Abstract: An apparatus and method for laser probing of a DUT at very high temporal resolution is disclosed. The system includes a CW laser source, a beam optics designed to point two orthogonally polarized beams at the same location on the DUT, optical detectors for detecting the reflected beams, collection electronics, and an oscilloscope. The beam optics defines a common-path polarization differential probing (PDP) optics. The common-path PDP optics divides the laser beam into two beams of orthogonal polarization. Due to the intrinsic asymmetry of a CMOS transistor, the interaction of the beams with the DUT result in different phase modulation in each beam. This difference can be investigated to study the response of the DUT to the stimulus signal.
    Type: Grant
    Filed: June 29, 2005
    Date of Patent: November 10, 2009
    Assignee: DCG Systems, Inc.
    Inventors: Steven Kasapi, Kenneth Wilsher, Gary Woods, William Lo, Radu Ispasoiu, Nagamani Nataraj, Nina Boiadjieva
  • Patent number: 7450245
    Abstract: A system for probing a DUT is provided, the system comprising a tunable or CW laser source, a modulator for modulating the output of the laser source, a beam optics designed to point a probing beam at a designated location on the DUT, optical detector for detecting the reflected beam, and collection and signal processing electronics. The system deciphers perturbations in the reflected beam by detecting beat frequency between operation frequency of the DUT and frequency of the modulation. In an alternative embodiment, the laser is CW and the modulation is applied to the optical detector.
    Type: Grant
    Filed: May 17, 2006
    Date of Patent: November 11, 2008
    Assignee: DCG Systems, Inc.
    Inventors: Gary Woods, Steven Kasapi, Kenneth Wilsher
  • Publication number: 20070046947
    Abstract: A system for probing a DUT is disclosed, the system having a pulsed laser source, a CW laser source, beam optics designed to point a reference beam and a probing beam at the same location on the DUT, optical detectors for detecting the reflected reference and probing beams, and a collection electronics. The beam optics is a common-path polarization differential probing (PDP) optics. The common-path PDP optics divides the incident laser beam into two beams of orthogonal polarization - one beam simulating a reference beam while the other simulating a probing beam. Both reference and probing beams are pointed to the same location on the DUT. Due to the intrinsic asymmetry of a CMOS transistor, the interaction of the reference and probing beams with the DUT result in different phase modulation in each beam. This difference can be investigated to study the response of the DUT to the stimulus signal.
    Type: Application
    Filed: October 27, 2005
    Publication date: March 1, 2007
    Applicant: Credence Systems Corporation
    Inventors: William Lo, Kenneth Wilsher, Nagamani Nataraj, Nina Boiadjieva
  • Publication number: 20070002329
    Abstract: An apparatus and method for laser probing of a DUT at very high temporal resolution is disclosed. The system includes a CW laser source, a beam optics designed to point two orthogonally polarized beams at the same location on the DUT, optical detectors for detecting the reflected beams, collection electronics, and an oscilloscope. The beam optics defines a common-path polarization differential probing (PDP) optics. The common-path PDP optics divides the laser beam into two beams of orthogonal polarization. Due to the intrinsic asymmetry of a CMOS transistor, the interaction of the beams with the DUT result in different phase modulation in each beam. This difference can be investigated to study the response of the DUT to the stimulus signal.
    Type: Application
    Filed: June 29, 2005
    Publication date: January 4, 2007
    Inventors: Steven Kasapi, Kenneth Wilsher, Gary Woods, William Lo, Radu Ispasoiu, Nagamani Nataraj, Nina Boiadjieva
  • Publication number: 20070002328
    Abstract: A system for probing a DUT is provided, the system comprising a tunable or CW laser source, a modulator for modulating the output of the laser source, a beam optics designed to point a probing beam at a designated location on the DUT, optical detector for detecting the reflected beam, and collection and signal processing electronics. The system deciphers perturbations in the reflected beam by detecting beat frequency between operation frequency of the DUT and frequency of the modulation. In an alternative embodiment, the laser is CW and the modulation is applied to the optical detector.
    Type: Application
    Filed: May 17, 2006
    Publication date: January 4, 2007
    Applicant: CREDENCE SYSTEMS CORPORATION
    Inventors: Gary Woods, Steven Kasapi, Kenneth Wilsher
  • Publication number: 20050160331
    Abstract: PICA probe system methods and apparatus are described, including methods and apparatus for calibrating an event timer having a coarse measurement capability in which time intervals defined by clock boundaries are counted and a fine measurement capability in which time between boundaries is interpolated using a voltage ramp.
    Type: Application
    Filed: October 26, 2004
    Publication date: July 21, 2005
    Inventor: Kenneth Wilsher
  • Publication number: 20050128471
    Abstract: A method and system of testing integrated circuits (IC) via optical coupling. The optical system includes an optical fiber, fixture and focussing element. In addition, channels are provided in the fixture mounted on the integrated circuit to accommodate the optical system. The fixture acts as a heat sink. As such, one or more photosensitive elements/targets on the integrated circuit are probed using light that is brought to a focus on each target site. The light causes latching of data into the integrated circuit (which is operating under influence of a test program) and formation of a test pattern output from the integrated circuit that is used to confirm proper functioning of the IC.
    Type: Application
    Filed: January 24, 2005
    Publication date: June 16, 2005
    Applicant: Credence Systems Corporation
    Inventors: Kenneth Wilsher, Steven Kasapi
  • Publication number: 20050109956
    Abstract: A system and method for determining precisely in-situ the endpoint of halogen-assisted charged particle beam milling of a hole or trench in the backside of the substrate of a flipchip packaged IC. The backside of the IC is mechanically thinned. Optionally, a coarse trench is then milled in the thinned backside of the IC using either laser chemical etching or halogen-assisted charged particle beam milling. A further small trench is milled using a halogen-assisted charged-particle beam (electron or ion beam). The endpoint for milling this small trench is determined precisely by monitoring the power supply leakage current of the IC induced by electron-hole pairs created by the milling process. A precise in-situ endpoint detection signal is generated by modulating the beam at a reference frequency and then amplifying that frequency component in the power supply leakage current with an amplifier, narrow-band amplifier or lock-in amplifier.
    Type: Application
    Filed: November 9, 2004
    Publication date: May 26, 2005
    Inventors: Theodore Lundquist, Kenneth Wilsher
  • Publication number: 20050051726
    Abstract: A single-photon detector includes a superconductor strip biased near its critical current. The superconductor strip provides a discernible output signal upon absorption of a single incident photon. In one example, the superconductor is a strip of NbN (niobium nitride). In another example, the superconductor strip meanders to increase its probability of receiving a photon from a light source. The single-photon detector is suitable for a variety of applications including free-space and satellite communications, quantum communications, quantum cryptography, weak luminescence, and semiconductor device testing.
    Type: Application
    Filed: October 19, 2004
    Publication date: March 10, 2005
    Applicant: Credence Systems Corporation
    Inventors: Roman Sobolewski, Grigory Gol'tsman, Alexey Semenov, Oleg Okunev, Kenneth Wilsher, Steven Kasapi
  • Publication number: 20050006602
    Abstract: A method and apparatus for laser-assisted fault mapping which synchronizes the laser control with the tester unit. The inventive method provides for laser-assisted pseudo-static fault mapping to localize defects in a device whose inputs are being stimulated dynamically by a tester. It further provides for laser-assisted dynamic soft error mapping, to localize in terms of location and to correlate with respect to a specific test vector, sensitive areas in a device by utilizing device performance criteria such as pass-fail status outputs. The apparatus includes a fully controllable dynamic laser stimulation apparatus connected to a control unit that provides complete synchronization with a tester unit.
    Type: Application
    Filed: July 9, 2004
    Publication date: January 13, 2005
    Inventors: Philippe Perdu, Romain Desplats, Felix Beaudoin, Praveen Vedagarbha, Martin Leibowitz, Kenneth Wilsher
  • Publication number: 20040173878
    Abstract: A method and apparatus for accessing internal nodes of an integrated circuit using a package substrate are provided. Embodiments of the present invention include an integrated circuit comprising an integrated circuit die comprising a principal side; a conductive element formed on the principal side of the integrated circuit die; a package substrate comprising a principal side facing the principal side of the integrated circuit die; a conductive element located on the principal side of the package substrate; a transmission path wherein a first end of the transmission path is coupled to the conductive element of the integrated circuit die and wherein a second end of the transmission path is coupled to the conductive element of the package substrate.
    Type: Application
    Filed: March 4, 2003
    Publication date: September 9, 2004
    Inventor: Kenneth Wilsher
  • Patent number: 6781218
    Abstract: A method and apparatus for accessing internal nodes of an integrated circuit using a package substrate are provided. Embodiments of the present invention include an integrated circuit comprising an integrated circuit die comprising a principal side; a conductive element formed on the principal side of the integrated circuit die; a package substrate comprising a principal side facing the principal side of the integrated circuit die; a conductive element located on the principal side of the package substrate; a transmission path wherein a first end of the transmission path is coupled to the conductive element of the integrated circuit die and wherein a second end of the transmission path is coupled to the conductive element of the package substrate.
    Type: Grant
    Filed: March 4, 2003
    Date of Patent: August 24, 2004
    Assignee: NPTest, Inc.
    Inventor: Kenneth Wilsher