Abstract: Bandwidth of a test channel is determined from a single port Time Domain Reflectometer (TDR) measurement with the channel terminated in a short or an open circuit. Bandwidth is estimated by: (1) making a TDR measurement of a channel terminated in a short or open circuit; (2) determining a maximum slope of the reflection from the TDR measurement; (2) calculating an interpolated rise or fall time, for example by taking 80% of the applied voltage between the 10% and 90% points, and then dividing the applied voltage by the maximum slope determined; (3) dividing the overall interpolated rise time by the square root of two to account for the TDR signal proceeding through the channel twice; (4) removing the contribution of rise time from measurement equipment; and (5) completing calculation of channel bandwidth using a formula to relate bandwidth to rise time, such as: bandwidth=0.35/rise time.

Abstract: Methods and apparatuses for testing semiconductor devices are disclosed. Over travel stops limit over travel of a device to be tested with respect to probes of a probe card assembly. Feedback control techniques are employed to control relative movement of the device and the probe card assembly. A probe card assembly includes flexible base for absorbing excessive over travel of the device to be tested with respect to the probe card assembly.

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.

Abstract: Contact structures are formed by building a core structure on a substrate and over coating the core structure with a material that is harder or has a greater yield strength than the material of the core structure. The core structure may be formed by attaching a wire to the substrate and spooling the wire out from a spool. While spooling the wire out, the spool may be moved to impart a desired shape to the wire. The wire is severed from the spool and over coated. As an alternative, the wire is not over coated. The substrate may be an electronic device, such as a semiconductor die.

Abstract: Techniques for performing wafer-level burn-in and test of semiconductor devices include a test substrate having active electronic components such as ASICs mounted to an interconnection substrate or incorporated therein, metallic spring contact elements effecting interconnections between the ASICs and a plurality of devices-under-test (DUTs) on a wafer-under-test (WUT), all disposed in a vacuum vessel so that the ASICs can be operated at temperatures independent from and significantly lower than the burn-in temperature of the DUTs. The spring contact elements may be mounted to either the DUTs or to the ASICs, and may fan out to relax tolerance constraints on aligning and interconnecting the ASICs and the DUTs. Physical alignment techniques are also described.

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.

Abstract: The present invention discloses a method and system compensating for thermally induced motion of probe cards used in testing die on a wafer. A probe card incorporating temperature control devices to maintain a uniform temperature throughout the thickness of the probe card is disclosed. A probe card incorporating bi-material stiffening elements which respond to changes in temperature in such a way as to counteract thermally induced motion of the probe card is disclosed including rolling elements, slots and lubrication. Various means for allowing radial expansion of a probe card to prevent thermally induced motion of the probe card are also disclosed. A method for detecting thermally induced movement of the probe card and moving the wafer to compensate is also disclosed.

Abstract: A mechanical support configuration for a probe card of a wafer test system is provided to increase support for a very low flexural strength substrate that supports spring probes. Increased mechanical support is provided by: (1) a frame around the periphery of the substrate having an increased sized horizontal extension over the surface of the substrate; (2) leaf springs with a bend enabling the leaf springs to extend vertically and engage the inner frame closer to the spring probes; (3) an insulating flexible membrane, or load support member machined into the inner frame, to engage the low flexural strength substrate farther away from its edge; (4) a support structure, such as support pins, added to provide support to counteract probe loading near the center of the space transformer substrate; and/or (5) a highly rigid interface tile provided between the probes and a lower flexural strength space transformer substrate.

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.

Abstract: A central test facility transmits wirelessly test data to a local test facility, which tests electronic devices using the test data. The local test facility transmits wirelessly response data generated by the electronic devices back to the central test facility, which analyzes the response data to determine which electronic devices passed the testing. The central test facility may provide the results of the testing to other entities, such as a design facility where the electronic devices were designed or a manufacturing facility where the electronic devices where manufactured. The central test facility may accept requests for test resources from any of a number of local test facilities, schedule test times corresponding to each test request, and at a scheduled test time, wirelessly transmits test data to a corresponding local test facility.

Abstract: An emitter follower or source follower transistor is provided in the channel of a wafer test system between a DUT and a test system controller to enable a low power DUT to drive a test system channel. A bypass resistor is included between the base and emitter of the emitter follower transistor to enable bidirectional signals to be provided between the DUT channel and test system controller, as well as to enable parametric tests to be performed. The emitter follower transistor and bypass resistor can be provided on the probe card, with a pull down termination circuit included in the test system controller. The test system controller can provide compensation for the base to emitter voltage drop of the emitter follower transistor.

Abstract: A cooling assembly includes a package with one or more dies cooled by direct cooling. The cooled package includes one or more dies with active electronic components. A coolant port allows a coolant to enter the package and directly cool the active electronic components of the dies.

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.

Abstract: An improved microelectronic spring structure, and method of making the same, are disclosed. The improvement comprises, in a spring contact of the type comprising a beam attached to a post, of replacing the post with a plurality of column elements. The beam component is thus provided with one or more column elements which both structurally support and electrically connect one end of the beam to an electronic component. The column elements are preferably comprised of relatively straight segments of wire elements that are ball-bonded to a substrate and are over-coated with suitable structural and/or conducting materials. In the alternative, the improvement comprises a single column element comprised of a relatively straight segment of wire that is ball-bonded to a substrate and over-coated with suitable structural and conducting materials, wherein the column element is essentially rigid.

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.

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.

Abstract: A transmission line includes a signal conductor and at least one varactor diode capacitively coupled to the signal conductor. The transmission line's signal path delay is a function of its shunt capacitance, and the varactor's capacitance forms a part of the transmission line's shunt capacitance. The transmission line's signal path delay is adjusted by adjusting a control voltage across the varactor diode thereby to adjust the varactor diode's capacitance.

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.

Abstract: An interconnection element and a method of forming an interconnection element. In one embodiment, the interconnection element includes a first structure and a second structure coupled to the first structure. The second structure coupled with the first material has a spring constant greater than the spring constant of the first structure alone. In one embodiment, the interconnection element is adapted to be coupled to an electronic component tracked as a conductive path from the electronic component. In one embodiment, the method includes forming a first (interconnection) structure coupled to a substrate to define a shape suitable as an interconnection in an integrated circuit environment and then coupling, such as by coating, a second (interconnection) structure to the first (interconnection) structure to form an interconnection element.

Abstract: A method of making a microelectronic spring contact array comprises forming a plurality of spring contacts on a sacrificial substrate and then releasing the spring contacts from the sacrificial substrate. Each of the spring contacts has an elongated beam having a base end. The method of making the array includes attaching the spring contacts at their base ends to a base substrate after they have been released entirely from the sacrificial substrate, so that each contact extends from the base substrate to a distal end of its beams. The distal ends are aligned with a predetermined array of tip positions. In an embodiment of the invention, the spring contacts are formed by patterning contours of the spring contacts in a sacrificial layer on the sacrificial substrate. The walls of patterned recesses in the sacrificial layer define side profiles of the spring contacts, and a conductive material is deposited in the recesses to form the elongated beams of the spring contacts.