Patents Assigned to FormFactor
  • Patent number: 6491968
    Abstract: A method including fabricating a multi-tiered structure to form a compact, resilient interconnect structure. Fabricating each tier or leaf includes, in one aspect, providing a base substrate material, and applying a masking material over the base substrate material. An opening is patterned in the masking material and a resilient element is formed in the opening. A resilient element is coupled to the resilient element to form the resulting product. The method includes repeating this process one or more times to fabricate a chip-level interconnection element. The interconnection element fabricated, in another aspect, is of a size suitable for contacting a packaged semiconductor device, such as in an LGA package.
    Type: Grant
    Filed: December 29, 1999
    Date of Patent: December 10, 2002
    Assignee: FormFactor, Inc.
    Inventors: Gaetan L. Mathieu, Benjamin N. Eldridge, Gary W. Grube
  • Publication number: 20020175697
    Abstract: A system for testing integrated circuit devices is disclosed in which a tester communicates with a known good device through a channel. Tester-DUT interface circuitry is provided for monitoring the channel while the tester is writing data as part of a test sequence to locations in the known good device. In response, the interface circuitry writes the data to corresponding locations in each of a number of devices under test (DUTs). The interface circuitry monitors the channel while the tester is reading from the locations in the known good device (KGD), and in response performs a comparison between DUT data read from the corresponding locations in the DUTs and expected responses obtained form the KGD.
    Type: Application
    Filed: July 29, 2002
    Publication date: November 28, 2002
    Applicant: FormFactor, Inc.
    Inventors: Charles A. Miller, Richard S. Roy
  • Patent number: 6483328
    Abstract: A probe card is provided for contacting an electric componet with raised contact elements. In particular, the present invention is useful for contacting a semiconductor wafer with resilient contact elements, such as springs. A probe card is designed to have terminals to mate with the contact elements on the wafer. In a preferred embodiment, the terminals are posts. In a preferred embodiment the terminals include a contact material suitable for repeated contacts. In one particularly preferred embodiment, a space transformer is prepared with contact posts on one side and terminals on the opposing side. An interposer with spring contacts connects a contact on the opposing side of the space transformer to a corresponding terminal on a probe card, which terminal is in turn connected to a terminal which is connectable to a test device such as a conventional tester.
    Type: Grant
    Filed: December 2, 1998
    Date of Patent: November 19, 2002
    Assignee: Formfactor, Inc.
    Inventors: Benjamin N. Eldridge, Gary W. Grube, Gaetan L. Mathieu
  • Patent number: 6482013
    Abstract: Spring contact elements having a base end portion, a contact end portion, and a central body portion. In a first embodiment, the spring contact elements provide for movement of a majority of the spring contact element characterized by a first spring constant. As the force and deflection increase, the movement of a rearward portion of the spring contact element will stop when a portion of the contact element abuts a portion of its mounting member while the movement of a forward portion will continue with a second and different spring constant. In a second embodiment, the spring contact elements include additional conductive and insulating layers formed about the contact element for controlling the impedance of the spring contact element throughout its range of motion. The additional conductive layer may be connected to ground.
    Type: Grant
    Filed: February 18, 1997
    Date of Patent: November 19, 2002
    Assignee: FormFactor, Inc.
    Inventors: Benjamin N. Eldridge, Gary W. Grube, Igor Y. Khandros, Gaetan L. Mathieu
  • Patent number: 6479308
    Abstract: A method and system for sealing or covering exposed fuses on a semiconductor device are disclosed. A semiconductor device prober incorporating a spray device for applying a sealing compound to individual fuses on a semiconductor device subsequent to testing the semiconductor device is disclosed. A method and system for sealing exposed fuses on a semiconductor device is disclosed which allows the sealing step to be performed either prior to or following singulation of the semiconductor device into individual dice.
    Type: Grant
    Filed: December 27, 2001
    Date of Patent: November 12, 2002
    Assignee: FormFactor, Inc.
    Inventor: Benjamin N. Eldridge
  • Patent number: 6480978
    Abstract: What is disclosed is a system for testing a plurality of integrated circuit devices under test (DUTs), that includes a tester having at least one set of tester input/output (I/O) lines, the tester providing data values for testing a single DUT on the set of tester I/O lines, and circuitry coupled to the set of tester I/O lines to receive the data values from the tester and to provide error values to the tester, the circuitry forwards the data values to each of the plurality of DUTs, the circuitry performs a first comparison of the values of two locations having corresponding addresses in different DUTs after reading from the locations, and in response generates the error values indicative of the first comparison. The circuitry may further perform a second comparison of the values of two different locations in the same DUT to generate further error values indicative of the second comparison.
    Type: Grant
    Filed: March 1, 1999
    Date of Patent: November 12, 2002
    Assignee: FormFactor, Inc.
    Inventors: Richard S. Roy, Charles A. Miller
  • Patent number: 6475822
    Abstract: Spring contact elements are fabricated by depositing at least one layer of metallic material into openings defined on a sacrificial substrate. The openings may be within the surface of the substrate, or in one or more layers deposited on the surface of the sacrificial substrate. Each spring contact element has a base end portion, a contact end portion, and a central body portion. The contact end portion is offset in the z-axis (at a different height) than the central body portion. The base end portion is preferably offset in an opposite direction along the z-axis from the central body portion. In this manner, a plurality of spring contact elements are fabricated in a prescribed spatial relationship with one another on the sacrificial substrate.
    Type: Grant
    Filed: December 29, 2000
    Date of Patent: November 5, 2002
    Assignee: FormFactor, Inc.
    Inventors: Benjamin N. Eldridge, Gary W. Grube, Igor Y. Khandros, Gaetan L. Mathieu
  • Patent number: 6476630
    Abstract: Signal paths within an interconnect structure linking input/output (I/O) ports of an integrated circuit (IC) tester and test points of an IC die on a wafer are tested for continuity, shorts and resistance by using the interconnect structure to access a similar arrangement of test points on a reference wafer. Conductors in the reference wafer interconnect groups of test points. The tester may then test the continuity of signal paths through the interconnect structure by sending test signals between pairs of its ports through those signal paths and the interconnecting conductors within the reference wafer. A parametric test unit within the tester can also determine impedances of the signal paths through the interconnect structure by comparing magnitudes of voltage drops across pairs of its I/O ports to magnitudes of currents it transmits between the I/O port pairs.
    Type: Grant
    Filed: May 9, 2000
    Date of Patent: November 5, 2002
    Assignee: FormFactor, Inc.
    Inventors: Ralph G. Whitten, Benjamin N. Eldridge
  • Patent number: 6476333
    Abstract: An interconnection contact structure assembly including an electronic component having a surface and a conductive contact carried by the electronic component and accessible at the surface. The contact structure includes an internal flexible elongate member having first and second ends and with the first end forming a first intimate bond to the surface of said conductive contact terminal without the use of a separate bonding material. An electrically conductive shell is provided and is formed of at least one layer of a conductive material enveloping the elongate member and forming a second intimate bond with at least a portion of the conductive contact terminal immediately adjacent the first intimate bond.
    Type: Grant
    Filed: October 21, 1996
    Date of Patent: November 5, 2002
    Assignee: FormFactor, Inc.
    Inventors: Igor Y. Khandros, Gaetan L. Mathieu
  • Publication number: 20020158723
    Abstract: In an interconnect system for providing access to a common I/O terminal for multiple circuit devices such as drivers, receivers and electrostatic protection devices implemented on an IC, each such device is provided with a separate contact pad within the IC. The contact pads are linked to one another and to the IC I/O terminal though inductive conductors such as bond wires, metalization layer traces in the IC, or legs of a forked, lithographically-defined spring contact formed on the IC. The conductor inductance isolates the capacitance of the circuit devices from one another, thereby improving characteristics of the frequency response of the interconnect system. The inductances of the conductors and various capacitances of the interconnect system are also appropriately adjusted to optimize desired interconnect system frequency response characteristics.
    Type: Application
    Filed: April 26, 2002
    Publication date: October 31, 2002
    Applicant: FORMFACTOR, INC.
    Inventor: Charles A. Miller
  • Patent number: 6468098
    Abstract: An electrical interconnect assembly and methods for making an electrical interconnect assembly. In one embodiment, an interconnect assembly includes a flexible wiring layer having a plurality of first contact elements and a fluid containing structure which is coupled to the flexible wiring layer. The fluid, when contained in the fluid containing structure, presses the flexible wiring layer towards a device under test to form electrical interconnections between the first contact elements and corresponding second contact elements on the device under test. In a further embodiment, an interconnect assembly includes a flexible wiring layer having a plurality of first contact terminals and a semiconductor substrate which includes a plurality of second contact terminals.
    Type: Grant
    Filed: August 17, 1999
    Date of Patent: October 22, 2002
    Assignee: FormFactor, Inc.
    Inventor: Benjamin N. Eldridge
  • Publication number: 20020145032
    Abstract: Interconnection elements for electronic components, exhibiting desirable mechanical characteristic (such as resiliency, for making pressure contacts) are formed by using a shaping tool (512) to shape an elongate core element (502) of a soft material (such as gold or soft copper wire) to have a springable shape (including cantilever beam, S-shape, U-shape), and overcoating the shaped core element with a hard material (such as nickel and its alloys), to impart to desired spring (resilient) characteristic to the resulting composite interconnection element. A final overcoat of a material having superior electrical qualities (e.g., electrical conductivity and/or solderability) may be applied to the composite interconnection element.
    Type: Application
    Filed: December 29, 2000
    Publication date: October 10, 2002
    Applicant: FORMFACTOR INC
    Inventors: Igor Y. Khandros, Thomas H. Dozier, Gary W. Grube, Gaetan L. Mathieu
  • Publication number: 20020145437
    Abstract: A probe card assembly includes a printed circuit board with tester contacts for making electrical connections to a semiconductor tester. The probe card assembly also includes a probe head assembly with probes for contacting a semiconductor device under test. One or more daughter cards is mounted to the printed circuit board such that they are substantially coplanar with the printed circuit board. The daughter cards may contain a circuit for processing test data, including test signals to be input into the semiconductor and/or response signals generated by the semiconductor device in response to the test signals.
    Type: Application
    Filed: April 10, 2001
    Publication date: October 10, 2002
    Applicant: FormFactor, Inc.
    Inventors: A. Nicholas Sporck, Makarand S. Shinde
  • Patent number: 6459343
    Abstract: In an interconnect system for providing access to a common I/O terminal for multiple circuit devices such as drivers, receivers and electrostatic discharge (ESD) protection devices implemented on an IC, each such device is provided with a separate contact pad within the IC. The contact pads are linked to one another and to the IC I/O terminal though inductive conductors such as bond wires, metalization layer traces in the IC, or legs of a forked, lithographically-defined spring contact formed on the IC. The conductor inductance isolates the capacitance of the circuit devices from one another, thereby improving characteristics of the frequency response of the interconnect system. Also the ESD protection function is distributed among multiple ESD devices interconnected by series inductors to provide a multi-pole filter at each IC terminal.
    Type: Grant
    Filed: February 22, 2000
    Date of Patent: October 1, 2002
    Assignee: Formfactor, Inc.
    Inventor: Charles A. Miller
  • Patent number: 6456103
    Abstract: A main power supply continuously provides a current to a power input terminal of an integrated circuit device under test (DUT). The DUT's demand for current at the power input terminal temporarily increases during state changes in synchronous logic circuits implemented within the DUT. To limit variation (noise) in voltage at the power input terminal arising from these temporary increases in current demand, a charged capacitor is connected to the power input terminal during each DUT state change. The capacitor discharges into the power input terminal to supply additional current to meet the DUT's increased demand. Following each DUT state change the capacitor is disconnected from the power input terminal and charged to a level sufficient to meet a predicted increase in current demand during a next DUT state change.
    Type: Grant
    Filed: October 30, 2001
    Date of Patent: September 24, 2002
    Assignee: Formfactor, Inc.
    Inventors: Benjamin N. Eldridge, Charles A. Miller
  • Patent number: 6456099
    Abstract: One embodiment of the present invention concerns an integrated circuit that includes bond pads and special contact pads or points. The bond pads are for interfacing the integrated circuit as a whole with an external circuit, and are to be bonded to a package or circuit board. The bond pads are disposed on the die in a predetermined alignment such as a peripheral, grid, or lead-on-center alignment. The special contact pads are used to provide external test patterns to internal circuits and/or to externally monitor results from testing the internal circuits. The special contact pads may be advantageously located on the integrated circuit with a high degree of positional freedom. For one embodiment, the special contact pads may be disposed on the die at a location that is not in the same alignment as the bond pads. The special contact pads may be smaller than the bond pads so as not to increase the die size due to the special contact pads.
    Type: Grant
    Filed: December 31, 1998
    Date of Patent: September 24, 2002
    Assignee: FormFactor, Inc.
    Inventors: Benjamin N. Eldridge, Igor Y. Khandros, David V. Pedersen, Ralph G. Whitten
  • Patent number: 6452411
    Abstract: A system for testing integrated circuit devices is disclosed in which a tester communicates with a known good device through a channel. Tester-DUT interface circuitry is provided for monitoring the channel while the tester is writing data as part of a test sequence to locations in the known good device. In response, the interface circuitry writes the data to corresponding locations in each of a number of devices under test (DUTs). The interface circuitry monitors the channel while the tester is reading from the locations in the known good device (KGD), and in response performs a comparison between DUT data read from the corresponding locations in the DUTs and expected responses obtained form the KGD.
    Type: Grant
    Filed: March 1, 1999
    Date of Patent: September 17, 2002
    Assignee: FormFactor, Inc.
    Inventors: Charles A. Miller, Richard S. Roy
  • Publication number: 20020125904
    Abstract: A power supply provides power to a power terminal of an integrated circuit device under test (DUT). The DUT's demand for current at the power input terminal may temporarily increase due, for example, to state changes in the DUT. To limit variation (noise) in voltage at the power input terminal, a supplemental current is supplied to the power input terminal.
    Type: Application
    Filed: January 30, 2002
    Publication date: September 12, 2002
    Applicant: FormFactor, Inc.
    Inventors: Benjamin N. Eldridge, Charles A. Miller
  • Patent number: 6448865
    Abstract: In an interconnect system for providing access to a common I/O terminal for multiple circuit devices such as drivers, receivers and electrostatic protection devices implemented on an IC, each such device is provided with a separate contact pad within the IC. The contact pads are linked to one another and to the IC I/O terminal though inductive conductors such as bond wires, metalization layer traces in the IC, or legs of a forked, lithographically-defined spring contact formed on the IC. The conductor inductance isolates the capacitance of the circuit devices from one another, thereby improving characteristics of the frequency response of the interconnect system. The inductances of the conductors and various capacitances of the interconnect system are also appropriately adjusted to optimize desired interconnect system frequency response characteristics.
    Type: Grant
    Filed: February 25, 1999
    Date of Patent: September 10, 2002
    Assignee: Formfactor, Inc.
    Inventor: Charles A. Miller
  • Patent number: 6442831
    Abstract: Interconnection elements for electronic components, exhibiting desirable mechanical characteristics (such as resiliency, for making pressure contacts) are formed by using a shaping tool (512) to shape an elongate core element (502) of a soft material (such as gold or soft copper wire) to have a springable shape (including cantilever beam, S-shape, U-shape), and overcoating the shaped core element with a hard material (such as nickel and its alloys), to impart a desired spring (resilient) characteristic to the resulting composite interconnection element. A final overcoat of a material having superior electrical qualities (e.g., electrical conductivity and/or solderability) may be applied to the composite interconnection element.
    Type: Grant
    Filed: January 24, 1997
    Date of Patent: September 3, 2002
    Assignee: FormFactor, Inc.
    Inventors: Igor Y. Khandros, Thomas H. Dozier, Gary W. Grube, Gaetan L. Mathieu