Patents Assigned to Essai, Inc.
  • Patent number: 8653842
    Abstract: Thermal control units (TCU) for maintaining a set point temperature on an IC device under test (DUT) are provided. The units include a pedestal assembly comprising a heat-conductive pedestal, a fluid circulation block, a thermoelectric module (Peltier device) between the heat-conductive pedestal and the block for controlling heat flow between the pedestal and fluid circulation block, and a force distribution block for controllably distributing a z-axis force between different pushers of the TCU. Alternatively, instead of a thermoelectric module, a heater can provide heat to the DUT. Optionally, a swivelable temperature-control fluid inlet and outlet arms may be provided to reduce instability of the thermal control unit due to external forces exerted on the TCU such as by fluid lines attached to the fluid inlet and outlet arms. Also optionally, an integrated means for abating condensation on surfaces of the TCU during cold tests may be provided.
    Type: Grant
    Filed: April 6, 2011
    Date of Patent: February 18, 2014
    Assignee: Essai, Inc.
    Inventors: Nasser Barabi, Chee Wah Ho, Joven R. Tienzo, Oksana Kryachek, Elena V. Nazarov
  • Publication number: 20140021972
    Abstract: A test socket assembly, useful in association with a thermal control unit (TCU) used to maintain a set point temperature on an IC device under test, has alignment holes with bushings that are secured within the alignment holes by using retaining pins. The retaining pins can be easily screwed in and out of the socket. This provision allows the bushings to be replaced easily as they get worn out or deformed from repeated testing.
    Type: Application
    Filed: July 12, 2013
    Publication date: January 23, 2014
    Applicant: Essai, Inc.
    Inventors: Nasser Barabi, Chee Wah Ho, Joven R. Tienzo, Oksana Kryachek, Elena V. Nazarov
  • Patent number: 8508245
    Abstract: Thermal control units (TCU) for maintaining a set point temperature on an IC device under test (DUT) are provided. The units include a pedestal assembly comprising a heat-conductive pedestal, a fluid circulation block, a thermoelectric module (Peltier device) between the heat-conductive pedestal and the block for controlling heat flow between the pedestal and fluid circulation block, and a force distribution block for controllably distributing a z-axis force between different pushers of the TCU. Optionally, a swivelable temperature-control fluid inlet and outlet arms may be provided to reduce instability of the thermal control unit due to external forces exerted on the TCU such as by fluid lines attached to the fluid inlet and outlet arms. Also optionally, an integrated means for abating condensation on surfaces of the TCU during cold tests may be provided.
    Type: Grant
    Filed: November 30, 2010
    Date of Patent: August 13, 2013
    Assignee: Essai, Inc.
    Inventors: Nasser Barabi, Elena Nazarov, Joven R. Tienzo, Chee-Wah Ho
  • Patent number: 8493085
    Abstract: A spring contact pin includes a depressible probe member having a tapered configuration that prevents contact between the projecting end of the probe member and the end of the spring barrel throughout the compression and release cycle of the probe. The tapered configuration of the depressible probe member improves the mechanical performance, reliability, and high-speed signal performance of the contact pin.
    Type: Grant
    Filed: March 29, 2010
    Date of Patent: July 23, 2013
    Assignee: Essai, Inc.
    Inventors: Nasser Barabi, Oksana Kryachek, Chee-Wah Ho
  • Publication number: 20100277191
    Abstract: A spring contact pin includes a depressible probe member having a tapered configuration that prevents contact between the projecting end of the probe member and the end of the spring barrel throughout the compression and release cycle of the probe. The tapered configuration of the depressible probe member improves the mechanical performance, reliability, and high-speed signal performance of the contact pin.
    Type: Application
    Filed: March 29, 2010
    Publication date: November 4, 2010
    Applicant: ESSAI, INC.
    Inventors: Nasser Barabi, Oksana Kryachek, Chee-Wah Ho
  • Patent number: 7663388
    Abstract: A thermal control unit (TCU) for maintaining the set point temperature of an IC device under test (DUT) has a thermoelectric module (a Peltier device), a fluid circulation block, a lower pedestal assembly containing a thermal sensor, and an upper cover housing arranged in a stacked relationship along the z-axis of the TCU. A z-axis compliant force is supplied from the TCU's cover housing by means of a spring-loaded pusher mechanism that supplies a compliant spring force to the stacked arrangement of the fluid block, peltier device, and pedestal assembly. The z-axis compliant force provided by the spring-loaded pusher mechanism produces efficient thermal contact between the peltier device and the stacked components of the TCU containing the peltier device and allows the peltier device to expand and contract within the TCU to extend the life of the peltier device.
    Type: Grant
    Filed: March 31, 2008
    Date of Patent: February 16, 2010
    Assignee: Essai, Inc.
    Inventors: Nasser Barabi, Elena Nazarov, Joven R. Tienzo, Chee-Wah Ho
  • Patent number: 7651340
    Abstract: An improved IC chip actuator cover assembly for an IC socket includes a pedestal assembly spring-mounted to the bottom of a carrier housing and side leaf springs or other similar force transferring means on the pedestal assembly which transmit a z-axis force to the corner regions of the pedestal assembly for advancing the pedestal assembly in the z-axis direction against an IC chip in the IC socket. The compliance of the leaf springs maintains a constant and precise actuating force on the IC chip when the IC chip is contacted by the pusher end portion or portions of the pedestal assembly. In a preferred aspect of the invention, the front, back, and sides of the carrier housing define a central cavity region above the pedestal assembly for permitting air flow through the carrier housing to improve the heat dissipation capability of the cover assembly.
    Type: Grant
    Filed: February 22, 2008
    Date of Patent: January 26, 2010
    Assignee: Essai, Inc.
    Inventors: Nasser Barabi, Oksana Kryachek, Chee-Wah Ho
  • Patent number: 7583097
    Abstract: An improved contactor nest for receiving and holding IC devices against a pin board interposer during the test or burn-in of the devices includes a frame having an IC pocket with a top opening, which is oversized in relation to the footprint of the IC device for which the contactor is designed, and centering guide walls for guiding an IC device to be tested into the pocket from the oversized top opening to the IC device seating plane. The centering guide walls have a gradual angle relative to the insertion axis of the IC pocket, and extend down to a bottom perimeter portion of the IC pocket immediately adjacent the IC seating plane for gradually centering the IC device in the pocket as the IC device approaches the seating plane. Preferably, the angled guide walls extend far enough into the IC pocket to allow the spring pins of the pin board interposer to scrub the contact pads of the IC devices as the IC device is being centered.
    Type: Grant
    Filed: December 20, 2006
    Date of Patent: September 1, 2009
    Assignee: Essai, Inc.
    Inventors: Nasser Barabi, Oksana Kryachek, Chee-Wah Ho