Abstract:
By segregating at least a substantial portion of the power connections to the space transformer component (506, 700, 800) from the signal connections thereto, constraints on the interposer component (504) may be relaxed. This is particularly advantageous in the context of probing one or more high power semiconductor components. The technique of the present invention provides for a plurality of signals (including power and ground) to be inserted into an electronic component such as a space transformer both from a one main surface thereof and an edge (periphery) thereof to an opposite main surface thereof. The space transformer includes pads (522, 706, 810) for engaging, by means of spring elements (524), component (508) to be tested and includes exposed edge pads (750, 804, 854) for engagement by a flexible cable (752) for transmission of power and ground signals to the space transformer. The system also includes an interposer (504) having resilient contacts (514, 516) for electrically interconnecting a probe card (502) to the space transformer (506).
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.degree. C., and can be completed in less than 60 minutes.
Abstract:
Interconnection elements and/or tip structures for interconnection elements may first be fabricated upon sacrificial substrates for subsequent mounting to electronic components. In this manner, the electronic components are not `at risk` during the fabrication process. The sacrificial substrate establishes a predetermined spatial relationship between the interconnection elements which may be composite interconnection elements having a relatively soft elongate element as a core and a relatively hard (springy material) overcoat. Tip structures fabricated on sacrificial substrates may be provided with a surface texture optimized for mounting to any interconnection elements for making pressure connections to terminals of electronic components. Interconnection elements may be fabricated upon such tip structures, or may first be mounted to the electronic component and the tip structures joined to the free-ends of the interconnection elements. Tip structures formed as cantilever beams are described.
Abstract:
The efficacy of electrical discharges for severing bond wires and/or for forming balls at the ends of bond wires (including bond wires already severed by alternative mechanisms) is improved by performing the electrical discharges in the presence of ultraviolet light. A "spark gap" is formed between an EFO electrode and the wire, one of which serves as the cathode of the spark gap. Preferably, the ultraviolet light is directed at the element serving as the cathode of the spark gap. Providing photoemission at the cathode element of the spark gap stabilizes arc/plasma formation and produces more reliable and predictable results. This technique may be used in conjunction with negative EFO systems or with positive EFO systems, and may benefit from either direct or field-assisted photoemission.
Abstract:
Surface-mount, solder-down sockets permit electronic components such as semiconductor packages to be releasably mounted to a circuit board. Resilient contact structures extend from a top surface of a support substrate, and solder-ball (or other suitable) contact structures are disposed on a bottom surface of the support substrate. Composite interconnection elements are used as the resilient contact structures disposed atop the support substrate. In any suitable manner, selected ones of the resilient contact structures atop the support substrate are connected, via the support substrate, to corresponding ones of the contact structures on the bottom surface of the support substrate. In an embodiment intended to receive a LGA-type semiconductor package, pressure contact is made between the resilient contact structures and external connection points of the semiconductor package with a contact force which is generally normal to the top surface of the support substrate. In an embodiment intended to receive a BGA-type semiconductor package, pressure contact is made between the resilient contact structures and external connection points of the semiconductor package with a contact force which is generally parallel to the top surface of the support substrate.
Abstract:
Techniques for testing an electronic device with through-device vias can include using a probe card assembly with probes for contacting connection structures of the electronic device including ends of through-device vias of the electronic device. A pair of the probes can be electrically connected in the probe card assembly and can thus contact and form a direct return loop from one through-device via to another through-device via of a pair of the through-device vias with which the pair of probes is in contact. The electronic device can include test circuitry for driving a test signal onto the one of the through-device vias and a receiver for detecting the test signal on the other of the through-device vias.
Abstract:
A fuel cell comprises an anode, a cathode, and a proton exchange membrane. The anode and cathode can include a catalyst layer which includes a plurality of generally aligned carbon nanotubes. Methods of making a fuel cell are also disclosed.
Abstract:
A probe head can comprise a substrate and electrically conductive structures extending from opposite surfaces of the substrate. The probe head can be made by forming frame structures each comprising a frame to which a row of the conductive structures is coupled. The frame structures can be placed in a stack. A compressible shim or a curable adhesive can be provided between adjacent frames in the stack to control a distance between the contact ends of the conductive structures in adjacent rows of the conductive structures. The frames can include cavities that form a mold while the frames are in the stack, and the substrate can be formed by introducing a moldable material into the mold. After the moldable material hardens, the frame can be removed, leaving the conductive structures embedded in the substrate.
Abstract:
Contact structures exhibiting resilience or compliance for a variety of electronic components are formed. A variety of materials for the wire stem (which serves as a falsework) and for the overcoat (which serves as a superstructure over the falsework) are disclosed. Various techniques are described for mounting the contact structures to a variety of electronic components (e.g., semiconductor wafers and dies, semiconductor packages, interposers, interconnect substrates, etc.), and various process sequences are described. The resilient contact structures described herein are ideal for making a “temporary” (probe) connections to an electronic component such as a semiconductor die, for burn-in and functional testing.
Abstract:
A robust mechanical structure is provided to prevent small foundation structures formed on a substrate from detaching from the substrate surface. The strengthened structure is formed by plating a foundation metal layer on a seed layer and then embedding the plated foundation structure in an adhesive polymer material, such as epoxy. Components, such as spring probes, can then be constructed on the plated foundation. The adhesive polymer material better assures the adhesion of the metal foundation structure to the substrate surface by counteracting forces applied to an element, such as a spring probe, attached to the plated foundation.