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. Generally, the invention is directed to making (pre-fabricating) relatively ‘perfect’ contact tip structures (“tips”) and joining them to relatively ‘imperfect’ interconnection elements to improve the overall capabilities of resulting “tipped” interconnection elements.
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.
Abstract:
A wafer test assembly includes multiple probe head substrates arranged like tiles with connectors attached to one side and probes supported on the opposing side. In one embodiment, flexible cable connectors directly connect the connectors on the probe head tile to a test head, while in another embodiment the flexible cables connect the probe head tile to a PCB providing horizontal routing to test head connectors. In one embodiment, leveling pins provide a simplified support structure connecting to a retaining element attached to the tiles to provide for applying a push-pull leveling force. A test head connector interface frame enables rearrangement of connectors between the test head and the probe card to provide for both full wafer contact or partial wafer contact. The test head connectors are rearranged by being slidable on rails, or pluggable and unpluggable enabling movement over a range of positions.
Abstract:
Contact structures exhibiting resilience or compliance for a variety of electronic components are formed by bonding a free end of a wire to a substrate, configuring the wire into a wire stem having a springable shape, severing the wire stem, and overcoating the wire stem with at least one layer of a material chosen primarily for its structural (resiliency, compliance) characteristics. A variety of techniques for configuring, severing, and overcoating the wire stem are disclosed. In an exemplary embodiment, a free end of a wire stem is bonded to a contact area on a substrate, the wire stem is configured to have a springable shape, the wire stem is severed to be free-standing by an electrical discharge, and the free-standing wire stem is overcoated by plating. 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. The self-same resilient contact structures can be used for subsequent permanent mounting of the electronic component, such as by soldering to a printed circuit board (PCB). An irregular topography can be created on or imparted to the tip of the contact structure to enhance its ability to interconnect resiliently with another electronic component. Among the numerous advantages of the present invention is the great facility with which the tips of a plurality of contact structures can be made to be coplanar with one another. Other techniques and embodiments, such as wherein the falsework wirestem protrudes beyond an end of the superstructure, or is melted down, and wherein multiple free-standing resilient contact structures can be fabricated from loops, are described.
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:
Probes of a probe card assembly can be adjusted with respect to an element of the probe card assembly, which can be an element of the probe card assembly that facilitates mounting of the probe card assembly to a test apparatus. The probe card assembly can then be mounted in a test apparatus, and an orientation of the probe card assembly can be adjusted with respect to the test apparatus, such as a structural part of the test apparatus or a structural element attached to the test apparatus.
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:
A wafer test assembly includes multiple probe head substrates arranged like tiles with connectors attached to one side and probes supported on the opposing side. In one embodiment, flexible cable connectors directly connect the connectors on the probe head tile to a test head, while in another embodiment the flexible cables connect the probe head tile to a PCB providing horizontal routing to test head connectors. In one embodiment, leveling pins provide a simplified support structure connecting to a retaining element attached to the tiles to provide for applying a push-pull leveling force. A test head connector interface frame enables rearrangement of connectors between the test head and the probe card to provide for both full wafer contact or partial wafer contact. The test head connectors are rearranged by being slidable on rails, or pluggable and unpluggable enabling movement over a range of positions.
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.
Abstract:
Methods are provided for making plated through holes usable for inserting and attaching connector probes. In a first method, a curved plated through hole is formed by bonding curved etchable wires to a first substrate, plating the wires with a non-etchable conductive material, encasing the plated wires with a dielectric material to form a second substrate, planing the second substrate to expose the etchable wire, and etching the wires to leave plated through holes. In a second method, wires coated with a first etchable layer are initially bonded to a substrate, a second non-etchable plating layer is then applied over the first layer, and the first layer is etched away leaving plated through holes with wires disposed inside. In a third embodiment, a layer of masking material is initially deposited on a substrate and etched to form holes which are filled with a sacrificial fill material, the masking material is then removed, the fill material plated, grinding is performed to remove some plating to expose the fill material, and the fill material is then etched away leaving plated attachment wells. Probes may be attached to the plated through holes or attachment wells to create resilient spring contacts to form a wafer probe card assembly. A twisted tube plated through hole structure is formed by supporting twisted sacrificial wires coated with the plating material in a substrate, and later etching away the wires.