Patents Assigned to FormFactor
  • Patent number: 6664628
    Abstract: The present invention provides an ancillary electrical component in very close proximity to a semiconductor device, preferably mounted directly to the semiconductor device. In one preferred embodiment, the ancillary electrical component is a capacitor. In a preferred embodiment, a terminal is provided on the semiconductor device such that the capacitor can be electrically connected directly to the terminals, as by soldering or with conductive epoxy. Connecting the capacitor between terminals of a power loop provides superior noise and transient suppression. The very short path between the capacitor and the active circuit provides for extremely low inductance, allowing for the use of relatively small capacitors. The semiconductor device then is connected to an electronic device such as a PC board for further connection to other circuitry.
    Type: Grant
    Filed: October 4, 2001
    Date of Patent: December 16, 2003
    Assignee: FormFactor, Inc.
    Inventors: Igor Y. Khandros, David V. Pedersen, Benjamin N. Eldridge, Richard S. Roy, Gaetan Mathieu
  • Patent number: 6661316
    Abstract: A printed circuit board (PCB) via, providing a conductor extending vertically between microstrip or stripline conductors formed on separate layers of a PCB, includes a conductive pad surrounding the conductor and embedded within the PCB between those PCB layers. The pad's shunt capacitance and the magnitudes of capacitances of other portions of the via are sized relative to the conductor's inherent inductance to optimize frequency response characteristics of the via.
    Type: Grant
    Filed: December 3, 2002
    Date of Patent: December 9, 2003
    Assignee: FormFactor, Inc.
    Inventors: Emad B. Hreish, Charles A. Miller
  • Publication number: 20030222667
    Abstract: In a probe card assembly, a series of probe elements can be arrayed on a silicon space transformer. The silicon space transformer can be fabricated with an array of primary contacts in a very tight pitch, comparable to the pitch of a semiconductor device. One preferred primary contact is a resilient spring contact. Conductive elements in the space transformer are routed to second contacts at a more relaxed pitch. In one preferred embodiment, the second contacts are suitable for directly attaching a ribbon cable, which in turn can be connected to provide selective connection to each primary contact. The silicon space transformer is mounted in a fixture that provides for resilient connection to a wafer or device to be tested. This fixture can be adjusted to planarize the primary contacts with the plane of a support probe card board.
    Type: Application
    Filed: June 10, 2003
    Publication date: December 4, 2003
    Applicant: FormFactor, Inc.
    Inventors: Igor Y. Khandros, A. Nicholas Sporck, Benjamin N. Eldridge
  • Patent number: 6655023
    Abstract: Resilient contact structures are mounted directly to bond pads on semiconductor dies, prior to the dies being singulated (separated) from a semiconductor wafer. This enables the semiconductor dies to be exercised (e.g., tested and/or burned-in) by connecting to the semiconductor dies with a circuit board or the like having a plurality of terminals disposed on a surface thereof. Subsequently, the semiconductor dies may be singulated from the semiconductor wafer, whereupon the same resilient contact structures can be used to effect interconnections between the semiconductor dies and other electronic components (such as wiring substrates, semiconductor packages, etc.). Using the all-metallic composite interconnection elements of the present invention as the resilient contact structures, burn-in can be performed at temperatures of at least 150° C., and can be comprised in less than 60 minutes.
    Type: Grant
    Filed: December 21, 1999
    Date of Patent: December 2, 2003
    Assignee: FormFactor, Inc.
    Inventors: Benjamin N. Eldridge, Gary W. Grube, Igor Y. Khandros, Gaetan L. Mathieu
  • Patent number: 6657455
    Abstract: A main power source supplies current through path impedance to a power terminal of an integrated circuit device under test (DUT). The DUT's demand for current at the power input terminal temporarily increases following edges of a clock signal applied to the DUT during a test as transistors within the IC switch in response to the clock signal edges. To limit variation (noise) in voltage at the power input terminal, an auxiliary power supply supplies an additional current pulse to the power input terminal to meet the increased demand during each cycle of the clock signal. The magnitude of the current pulse is a function of a predicted increase in current demand during that clock cycle, and of the magnitude of an adaption signal controlled by a feedback circuit provided to limit variation in voltage developed at the DUT's power input terminal.
    Type: Grant
    Filed: July 25, 2002
    Date of Patent: December 2, 2003
    Assignee: FormFactor, Inc.
    Inventors: Benjamin N. Eldridge, Charles A. Miller
  • Patent number: 6646520
    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: August 2, 2002
    Date of Patent: November 11, 2003
    Assignee: FormFactor, Inc.
    Inventor: Charles A. Miller
  • Patent number: 6644982
    Abstract: An apparatus for use in manipulating one or more IC die through testing after they have been cut from the original wafer. A carrier supports the die during the transport, testing, and/or final application. The die is placed into the carrier through an opening and then resides on a ledge lining some portion of the base of the opening. The spring components of the die extend downward through the opening and past the lower side of the ledge to allow for electrical contact. The die may be secured within the carrier opening in a variety of ways, including a cover coupled to the top of the carrier or through use of snap locks in the carrier. One useful cover has openings revealing a portion of the backside of the die. The cover openings allow access to the backside of the die. The carrier can be mounted onto a test bed for testing or a printed circuit board for a specific application. Alternatively, the carrier may first be positioned on the board with the die and the cover subsequently mounted thereon.
    Type: Grant
    Filed: March 1, 1999
    Date of Patent: November 11, 2003
    Assignee: FormFactor, Inc.
    Inventors: Douglas S. Ondricek, David V. Pedersen
  • Patent number: 6640415
    Abstract: A method of fabricating a large area, multi-element contactor. A segmented contactor is provided for testing semiconductor devices on a wafer that comprises a plurality of contactor units mounted to a substrate. The contactor units are formed, tested, and assembled to a backing substrate. The contactor units may include leads extending laterally for connection to an external instrument such as a burn-in board. The contactor units include conductive areas such as pads that are placed into contact with conductive terminals on devices under test.
    Type: Grant
    Filed: July 25, 2002
    Date of Patent: November 4, 2003
    Assignee: FormFactor, Inc.
    Inventors: Mohammad Eslamy, David V Pedersen, Harry D. Cobb
  • Patent number: 6642625
    Abstract: Temporary connections to spring contact elements extending from an electronic component such as a semiconductor device are made by urging the electronic component, consequently the ends of the spring contact elements, vertically against terminals of an interconnection substrate, or by horizontally urging terminals of an interconnection substrate against end portions of the spring contact elements. A variety of terminal configurations are disclosed.
    Type: Grant
    Filed: November 19, 2002
    Date of Patent: November 4, 2003
    Assignee: FormFactor, Inc.
    Inventors: Thomas H. Dozier, II, Benjamin N. Eldridge, Gary W. Grube, Igor Y. Khandros, Gaetan L. Mathieu, David V. Pederson, Michael A. Stadt
  • Patent number: 6640432
    Abstract: A method of fabricating and using an interconnection element that includes a first element material adapted to be coupled to a substrate and a second element material comprising a material having a transformable property such that upon transformation, a shape of the interconnection is deformed. An example is a material that has a transformable property such that a volume of the first and/or second element material may undergo a thermal transformation from one volume to a different volume (such as a smaller volume) resulting in the deformation of the interconnection element.
    Type: Grant
    Filed: April 12, 2000
    Date of Patent: November 4, 2003
    Assignee: FormFactor, Inc.
    Inventors: Gaetan L. Mathieu, Benjamin N. Eldridge, Stuart W. Wenzel
  • Publication number: 20030199179
    Abstract: Contact tip structures are fabricated on sacrificial substrates for subsequent joining to interconnection elements including composite interconnection elements, monolithic interconnection elements, tungsten needles of probe cards, contact bumps of membrane probes, and the like. The spatial relationship between the tip structures can lithographically be defined to very close tolerances. The metallurgy of the tip structures is independent of that of the interconnection element to which they are attached, by brazing, plating or the like. The contact tip structures are readily provided with topological (small, precise, projecting, non-planar) contact features, such as in the form of truncated pyramids, to optimize electrical pressure connections subsequently being made to terminals of electronic components. Elongate contact tip structures, adapted in use to function as spring contact elements without the necessity of being joined to resilient contact elements are described.
    Type: Application
    Filed: September 14, 2001
    Publication date: October 23, 2003
    Applicant: FormFactor, Inc.
    Inventors: Thomas H. Dozier, Benjamin N. Eldridge, Igor Y. Khandros, Gaetan L. Mathieu, Sheldon A. Taylor
  • Patent number: 6627483
    Abstract: A method for mounting an electronic component. In one example of this method, the electronic component is an integrated circuit which is placed against an element of a carrier, such as a frame of a carrier. The electronic component has a plurality of elongate, resilient, electrical contact elements which are mounted on a corresponding first electrical contact pads on the electronic component. The electronic component is secured to the carrier, aNd the carrier is pressed against a first substrate having a plurality of second electrical contacts on a surface of the first substrate. In a typical example of this method, the electronic component is an integrated circuit which is being tested while being held in a carrier. The integrated circuit has been singulated from a wafer containing a plurality of integrated circuits.
    Type: Grant
    Filed: March 1, 1999
    Date of Patent: September 30, 2003
    Assignee: FormFactor, Inc.
    Inventors: Douglas S. Ondricek, David V. Pedersen
  • Patent number: 6627980
    Abstract: A three-dimensional, stacked semiconductor device assembly with microelectronic spring contacts, and components thereof, is disclosed. The assembly comprises a plurality of stacked modules, which are capable of being readily mounted to, and demounted from, one another. Each module of the assembly comprises a semiconductor device, comprising a die, mounted to an stacking substrate. The die and the stacking substrate are optionally capable of being readily mounted to, and demounted from one another. A bottommost module in the assembly is suitable for attaching directly to a substrate or other component, such as a printed circuit board, and a topmost component in the assembly preferably comprises a decoupling and/or termination substrate. Each semiconductor device in the assembly has terminals on a surface thereof, at least selected ones of which are provided with an contact element. In addition, each device preferably comprises one or more stop structures for the microelectronic springs on its terminal surface.
    Type: Grant
    Filed: April 12, 2001
    Date of Patent: September 30, 2003
    Assignee: FormFactor, Inc.
    Inventor: Benjamin N. Eldridge
  • Patent number: 6624648
    Abstract: A probe card assembly includes a probe card, a space transformer, and an interposer disposed between the space transformer and the probe card. Suitable mechanisms for adjusting the orientation of the space transformer without changing the orientation of the probe card, and for determining what adjustments to make, are disclosed.
    Type: Grant
    Filed: December 5, 2001
    Date of Patent: September 23, 2003
    Assignee: FormFactor, Inc.
    Inventors: Benjamin N. Eldridge, Gary W. Grube, Igor Y. Khandros, Gaetan L. Mathieu
  • Patent number: 6621260
    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 29, 2000
    Date of Patent: September 16, 2003
    Assignee: FormFactor, Inc.
    Inventors: Benjamin N. Eldridge, Igor Y. Khandros, David V. Pedersen, Ralph G. Whitten
  • Patent number: 6622103
    Abstract: A timing calibration system for a wafer level integrated circuit (IC) tester is disclosed. The tester includes channels linked by paths through an interconnect system to pads of the IC. During a test each channel may send a test signal edge to an IC pad following a clock signal edge with a delay including “programmable drive” delay and “drive calibration” delay components, or may sample an IC output signal following the clock signal edge with a delay including “programmable compare” delay and adjustable “compare calibration” delay components. The interconnect system also links a spare channel to a point on the IC. To adjust the compare calibration delay of each channel, the interconnect system sequentially connects the tester channels to interconnect areas on a “calibration” wafer instead of to the IC on the wafer to be tested. Each interconnect area provides a path linking a channel to be calibrated to the spare channel.
    Type: Grant
    Filed: June 20, 2000
    Date of Patent: September 16, 2003
    Assignee: FormFactor, Inc.
    Inventor: Charles A. Miller
  • Publication number: 20030169061
    Abstract: An interconnect structure employs a closed-grid bus to link an integrated circuit tester channel to an array of input/output (I/O) pads on a semiconductor wafer so that the tester channel can concurrently communicate with all of the I/O pads. The interconnect structure includes a circuit board implementing an array of bus nodes, each corresponding to a separate one of the I/O pads. The circuit board includes at least two layers. Traces mounted on a first layer form a set of first daisy-chain buses, each linking all bus nodes of a separate row of the bus node array. Traces mounted on a second circuit board layer form a set of second daisy-chain buses, each linking all bus nodes of a separate column of the bus node array. Vias and other circuit board interconnect ends of the first and second daisy-chain buses so that they form the closed-grid bus. Each bus node is connected though a separate isolation resistor to a separate contact pad mounted on a surface of the circuit board.
    Type: Application
    Filed: April 2, 2003
    Publication date: September 11, 2003
    Applicant: FORMFACTOR, INC.
    Inventors: Charles A. Miller, John Matthew Long
  • Patent number: 6615485
    Abstract: A probe card assembly includes a probe card, a space transformer having resilient contact structures (probe elements) mounted directly to (i.e., without the need for additional connecting wires or the like) and extending from terminals on a surface thereof, and an interposer disposed between the space transformer and the probe card. The space transformer and interposer are “stacked up” so that the orientation of the space transformer, hence the orientation of the tips of the probe elements, can be adjusted without changing the orientation of the probe card. Suitable mechanisms for adjusting the orientation of the space transformer, and for determining what adjustments to make, are disclosed.
    Type: Grant
    Filed: December 27, 2001
    Date of Patent: September 9, 2003
    Assignee: FormFactor, Inc.
    Inventors: Benjamin Niles Eldridge, Gary William Grube, Igor Yan Khandros, Gaetan L. Mathieu
  • Patent number: 6616966
    Abstract: A method of forming an interconnection, including a spring contact element, by lithographic techniques. In one embodiment, the method includes applying a masking material over a first portion of a substrate, the masking material having an opening which will define a first portion of a spring structure, depositing a structure material (e.g., conductive material) in the opening, and overfilling the opening with the structure material, removing a portion of the structure material, and removing a first portion of the masking material. In this embodiment, at least a portion of the first portion of the spring structure is freed of masking material. In one aspect of the invention, the method includes planarizing the masking material layer and structure material to remove a portion of the structure material. In another aspect, the spring structure formed includes one of a post portion, a beam portion, and a tip structure portion.
    Type: Grant
    Filed: February 26, 2001
    Date of Patent: September 9, 2003
    Assignee: FormFactor, Inc.
    Inventors: Gaetan L. Mathieu, Benjamin N. Eldridge, Gary W. Grube
  • Patent number: 6606575
    Abstract: To calibrate timing of test signals generated by all channels of an integrated circuit, each channel is programmed to generate a test signal having a repetitive pseudo-random test signal edge pattern. The test signal pattern of each channel is compared to a reference signal having the same edge pattern and the delay of each channel is adjusted to maximize cross-correlation between the test signal and the reference signal.
    Type: Grant
    Filed: December 29, 2000
    Date of Patent: August 12, 2003
    Assignee: FormFactor, Inc.
    Inventor: Charles A. Miller