EP1275150A2 - Ressorts faconnes et leurs procedes de fabrication et d'utilisation - Google Patents

Ressorts faconnes et leurs procedes de fabrication et d'utilisation

Info

Publication number
EP1275150A2
EP1275150A2 EP01922806A EP01922806A EP1275150A2 EP 1275150 A2 EP1275150 A2 EP 1275150A2 EP 01922806 A EP01922806 A EP 01922806A EP 01922806 A EP01922806 A EP 01922806A EP 1275150 A2 EP1275150 A2 EP 1275150A2
Authority
EP
European Patent Office
Prior art keywords
element material
interconnection
substrate
assembly
electronic component
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP01922806A
Other languages
German (de)
English (en)
Inventor
Gaetan L. Mathieu
Benjamin N. Eldridge
Stuart W. Wenzel
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
FormFactor Inc
Original Assignee
FormFactor Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from US09/547,560 external-priority patent/US6640432B1/en
Priority claimed from US09/547,561 external-priority patent/US7458816B1/en
Application filed by FormFactor Inc filed Critical FormFactor Inc
Publication of EP1275150A2 publication Critical patent/EP1275150A2/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
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    • G01R1/02—General constructional details
    • G01R1/06—Measuring leads; Measuring probes
    • G01R1/067—Measuring probes
    • G01R1/06711—Probe needles; Cantilever beams; "Bump" contacts; Replaceable probe pins
    • G01R1/06755—Material aspects
    • G01R1/06761—Material aspects related to layers
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    • H01L23/48—Arrangements for conducting electric current to or from the solid state body in operation, e.g. leads, terminal arrangements ; Selection of materials therefor
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    • H01L24/10—Bump connectors ; Manufacturing methods related thereto
    • H01L24/11—Manufacturing methods
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    • H01L24/10—Bump connectors ; Manufacturing methods related thereto
    • H01L24/12—Structure, shape, material or disposition of the bump connectors prior to the connecting process
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    • G01R1/067—Measuring probes
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    • G01R1/06733—Geometry aspects
    • G01R1/06744—Microprobes, i.e. having dimensions as IC details
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    • G01R1/07342—Multiple probes with individual probe elements, e.g. needles, cantilever beams or bump contacts, fixed in relation to each other, e.g. bed of nails fixture or probe card the body of the probe being at an angle other than perpendicular to test object, e.g. probe card
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Definitions

  • the invention relates to an interconnection (contact) element suitable for effective connections between electronic components .
  • Interconnection or contact elements may be used to connect devices of an electronic component or one electronic component to another electronic component.
  • an interconnection element may be used to connect two circuits of an integrated circuit chip or to connect an application specific integrated circuit (ASIC) .
  • Interconnection elements may also be used to connect the integrated circuit chip to a chip package suitable for mounting on a printed circuit board (PCB) of a computer or other electronic device or to connect the integrated circuit chip directly to the PCB.
  • Interconnection elements may further be used to connect the integrated circuit chip to a test device such as a probe card assembly or other substrate to test the chip.
  • interconnection or contact elements between electronic components can be classified into at least the two broad categories of "relatively permanent" and “readily demountable. "
  • a "relatively permanent" contact element is a wire bond. Once two electronic components are connected to one another by a bonding of an interconnection element to each electronic component, a process of unbonding must be used to separate the components.
  • a wire bond interconnection element such as between an integrated circuit chip or die and inner leads of a chip or package (or inner ends of lead frame fingers) typically utilizes a “relatively permanent" interconnection element.
  • a "readily demountable" interconnection element is the interconnection element between rigid pins of one electronic component received by resilient socket elements of another electronic component, for example, a spring-loaded GA socket or a zero-insertion force socket.
  • a second type of a "readily demountable” interconnection element is an interconnection element that itself is resilient or springlike or mounted in or on a spring or resilient medium.
  • An example of such an interconnection element is a tungsten needle or a micro-spring contact of a probe card component such as described in commonly assigned U.S. Patent No. 5,974,662, titled “Method of Planarizing Tips of Probe Elements of a Probe Card Assembly," issued November 2, 1999 (FFI-P06) .
  • the interconnection element of a probe card component is typically intended to effect a temporary pressure connection between an electronic component to which the interconnection element is mounted and terminals of a second electronic component, such as a semiconductor device under test.
  • a minimum contact force is desired to effect reliable pressure contact to an electronic component (e.g., to terminals of an electronic component) .
  • a contact (load) force of approximately 15 grams (including as little as 2 grams or less and as much as 150 grams or more, per terminal) may be desired to effect a reliable electrical pressure connection to a terminal of an electronic component.
  • a second factor of interest with regard to spring interconnection elements is the shape and metallurgy of the portion of the interconnection element making pressure connection to the terminal of the electronic component.
  • the contact end is limited by the metallurgy of the element (i.e., tungsten) and, as the tungsten needle becomes smaller in diameter, it becomes commensurately more difficult to control or establish a desired shape at the contact end.
  • the element i.e., tungsten
  • interconnection elements themselves are not resilient, but rather are supported by a resilient membrane.
  • Membrane probes exemplify this situation, where a plurality of microbumps are disposed on a resilient membrane. Again, the technology required to manufacture such contact elements limits the design choices for the shape and metallurgy of the contact portion of the contact elements.
  • exemplary materials for the core element include gold.
  • exemplary materials for the coating include nickel and its alloys.
  • the resulting spring interconnection element is suitably used to effect pressure, or demountable, interconnections between two or more electronic components, including semiconductor devices.
  • spring interconnection elements are formed on a substrate, including a substrate that is an electronic component, by depositing and patterning a plurality of masking layers to form an opening corresponding to a shape embodied for the spring interconnection element, depositing conductive material in the opening made by the patterned masking layers, and removing the masking layer to form the free-standing spring interconnection element .
  • U.S. Patent No. 5,613,861 (and its counterpart divisional U.S. Patent No. 5,848,685) issued to Smith et al . disclose photolithographically patterned spring interconnection elements formed on a substrate with a body having an inherent stress gradient formed of a resilient (e.g., elastic) material such as chrome-molybdenum alloy or a nickel-zirconium alloy.
  • the stress gradient causes an end of the body to bend away from the substrate in the shape of an arc when the end is freed from the substrate.
  • a limit on the thickness of the interconnection element limits the spring constant, k, of the interconnection element (k increases as thickness increases) particularly in state-of-the-art interconnection element arrays where the dimensions (e.g., length and width) of individual interconnection arrays are reduced to accommodate a corresponding increase in contact pad or terminal density.
  • F load or force
  • the interconnection element includes a first element material adapted to be coupled to a substrate and a second element material coupled to the first element material. At least one of the first element material and the second element material comprises a material having a transformable property such that upon transformation, a shape of the interconnection element is deformed.
  • a first and/or second element material having a property such that a first volume of the material is adapted to be transformed to a second, different volume.
  • One portion of the interconnection element of the invention may be coupled to a substrate such as an electronic component and in electrical communication with a signal at the substrate.
  • the interconnection element may adopt a variety of configurations to allow elastic deformation when interconnecting two electronic components.
  • One preferred embodiment is a configuration of a cantilever where a free end of the interconnection element is available for electrical connection, such as to probe contact pads or terminals of another electronic component or electrically couple two electronic components.
  • the first element material and the second element material of the interconnection element are arranged in a configuration such that the second element material overlies the first element material and the first volume is greater than the second volume.
  • the transformation to a smaller second volume causes the interconnection element to deform along some portion of its length.
  • the volume transformation will cause, in one embodiment, the free end of the interconnection element to deform away (i.e., deflect) from the substrate with the free end arcing toward the coupled base, thus providing a projecting interconnection element.
  • the distance that an interconnection may deflect from the substrate may be limited by, for example, a travel stop so that, in one instance, a consistent deflection distance may be established for a plurality of interconnection elements on a substrate (or above the substrate) .
  • the second element material may be retained or removed, to yield a bi-material or mono-material interconnection element, respectively.
  • the bi-material or mono-material interconnection element may also serve as a precursor or core to a final interconnection structure, the final structure formed by incorporating additional materials or layers, e.g., resilient layers, to form the interconnection element.
  • the electronic assembly includes a substrate having a plurality of contact nodes accessible on the substrate and a plurality of free-standing resilient interconnection elements coupled to the substrate in such a manner that an attachment element or a base of an interconnection element electrically contacts a corresponding one of the contact nodes.
  • the contact nodes are signal lines on or in the substrate.
  • the interconnection element comprises, in one aspect, a first element material adapted to be coupled to a substrate, and a second element material coupled to the first element material .
  • One of the first element material and the second element material comprises a material having a transformable property such that upon transformation, a shape of the interconnection element is deformed.
  • One example is a first and/or second element material having a property such that a first volume of the material is adapted to be transformed to a different second volume .
  • a method is further disclosed.
  • the method includes creating an interconnection element coupled to a substrate and comprising a first element material and a second element material; releasing the interconnection element from the substrate at one end; and transforming a property of one of the first element material and the second element material to deform the interconnection element.
  • a property transformation is transforming the volume of one of the first element material and the second element material from a first volume to a second, different volume.
  • the release of the one end of the interconnection element may occur before or after the transformation step.
  • the interconnection element may adopt a variety of configurations such as a cantilever where a free end of the interconnection element is available for electrical connection, such as to probe or electrically couple an electronic assembly.
  • the second element material may overly the first element material such that, in one embodiment, a volume transformation, for example, results in the second volume being less than the first volume.
  • a volume transformation for example, results in the second volume being less than the first volume.
  • the free end of the interconnection element may deform upon transformation to move the free end of the contact away from the substrate.
  • the second element material may be removed to create a mono-material interconnection element. This latter operation is particularly useful where the remaining material is in a state where it will retain, at least more or less, the modified shape.
  • the interconnection element formed by the method of the invention may stand alone or may serve as a precursor to a final interconnection structure.
  • the method includes, after the transformation step, patterning a masking material over the substrate to have an opening exposing the surface of the interconnection element and coating a third element material, such as a resilient material, on the exposed surface of the interconnection element to increase the spring constant of the interconnection element.
  • a masking material is an electrophoretic resist material that may be introduced onto the surface of the substrate.
  • One advantage of using the electrophoretic resist material as the masking material is that it may be introduced uniformly over the surface without disrupting (e.g., damaging) the interconnection element or elements on the substrate.
  • Products including the new contact elements can be secured to a second electronic component by means of pressure, as in a holding fixture or a probing apparatus for testing wafers. Products also can be secured more permanently, as by soldering, much as in conventional mounting of ICs to system boards .
  • Figure 1 illustrates a cross-sectional side view of a portion of an electronic component having a plurality of contact pads with a shorting layer over the pads.
  • Figure 2 illustrates the structure of Figure 1 after the patterning of a masking material over the substrate and having openings to the plurality of contact pads according to a first embodiment of the invention.
  • Figure 3 shows the structure of Figure 1 after a thermal treatment .
  • Figure 4 shows the structure of Figure 1 after the conformal introduction of an activation layer over the top surface of a structure.
  • Figure 5 shows the structure of Figure 1 after the patterning of a second masking material over the top surface of a structure.
  • Figure 6 shows the structure of Figure 1 after the introduction of first element material in openings defined by the second masking material .
  • Figure 7 shows the structure of Figure 1 after the introduction of second element material over the first element material .
  • Figure 8 shows the structure of Figure 1 after the removal of the second masking material .
  • Figure 9 shows the structure of Figure 1 after the removal of exposed adhesion layer material.
  • Figure 10 shows the structure of Figure 1 after the removal of the first masking material.
  • Figure 11 shows the structure of Figure 1 after inducing a volumetric change in the second element material .
  • Figure 12 shows the structure of Figure 1 after the conformal deposition of a third masking material.
  • Figure 13 shows the structure of Figure 1 defining the third masking material .
  • Figure 14 shows the structure of Figure 1 after the definition of the third masking material to have an opening to the second element material .
  • Figure 15 shows the structure of Figure 1 after the introduction of third element material over the exposed portions of the second element material.
  • Figure 16 shows the structure of Figure 1 after the introduction of a probe material over the third element material.
  • Figure 17 shows the structure of Figure 1 after the removal of the third masking material.
  • Figure 18 shows the structure of Figure 1 after the introduction of travel stop material.
  • Figure 19 shows the structure of Figure 1 after patterning the travel stop material.
  • Figure 20 shows the structure of Figure 1 after introduction of a second contact material .
  • Figure 21 shows a graphical representation of the deflection distance of an interconnection element of a first element material of palladium/cobalt alloy of 200 micro-inches (about 5 ⁇ m) and varying thickness of a second element material of nickel/cobalt alloy.
  • Figure 22 illustrates a cross-sectional side view of a portion of an electronic component having a shorting layer over contact pads, a masking material over the shorting layer, an activation layer over the masking material, and first element material introduced and patterned over the activation layer in accordance with another embodiment of the invention.
  • Figure 23 shows the structure of Figure 22 after the introduction of a shape memory alloy (SMA) material in a martinsite state over the patterned first element material.
  • SMA shape memory alloy
  • Figure 24 shows the structure of Figure 22 after the patterning of the SMA material.
  • Figure 25 shows the structure of Figure 22 after the removal of the first element material .
  • Figure 26 shows the structure of Figure 22 after the transformation of the SMA material to its memory state.
  • Figure 27 shows the structure of Figure 22 after the removal of the SMA material.
  • Figure 28 shows the structure of Figure 22 after the introduction of probe material and contact material to each interconnection element and the patterning of travel stop material.
  • an interconnection element includes at least two materials and one or both of the materials is adapted to undergo a transformation to deform the shape of the interconnection element.
  • a transformation to deform the shape of the interconnection element is a volume transformation of at least one of the materials from a first volume to a second, different volume, the volume transformation bringing about a change in the shape of the interconnection element.
  • the invention describes an interconnection element having improved characteristics over prior art interconnection elements thus improving the suitability of the interconnection element of the invention for use in present and future, reduced-sized applications, including providing a conductive path between electronic components such as in contacting and/or testing of contact pads or terminals of an electronic component.
  • the following discussion describes the transformation (e.g., volume transformation) of at least one of two interconnection materials to deform (e.g., modify) the shape of the interconnection element.
  • volume transformation transformation of at least one of two interconnection materials to deform (e.g., modify) the shape of the interconnection element.
  • Such scenarios include, but are not limited to, a second element material that undergoes a volume transformation to a smaller volume; a first element material that undergoes a volume transformation to a larger volume; a first element material and a second element material (and possibly additional materials) that each undergo a volume transformation to deform an interconnection element; and two materials with different stress properties that will deform the shape of an interconnection element, for example, through a heat treatment.
  • a second element material that undergoes a volume transformation to a smaller volume
  • a first element material that undergoes a volume transformation to a larger volume
  • a first element material and a second element material (and possibly additional materials) that each undergo a volume transformation to deform an interconnection element
  • two materials with different stress properties that will deform the shape of an interconnection element, for example, through a heat treatment.
  • the behavior of metallic materials under temperature changes is understood in the art and the invention capitalizes on this behavior in designing interconnection elements with improved resiliency and spring constants in a simplified manner.
  • suitable electronic components include, but are not limited to, an active semiconductor device; a memory chip; a portion of a semiconductor wafer including a semiconductor wafer or die, made of any suitable semiconductor material such as silicon (Si) or gallium arsenide (GaAs) ; a ceramic substrate; an organic substrate; a printed circuit board (PCB) ; an organic membrane; a polyimide sheet; a space transformer; a probe card; a chip carrier; a production interconnect socket; a test socket; a sacrificial member; a semiconductor package including, but not limited to, ceramic and plastic packages and chip carriers; and a connector.
  • the electronic component may be an active device or a passive device that supports one or more electronic connections.
  • suitable electronic components include, but are not limited to, devices comprising an integrated circuit having at least two contact pads or terminals providing electrical access to the circuit.
  • Such a device is representatively demonstrated by an integrated circuit chip (or micro-chip) having a plurality of exposed contact pads or terminals providing access to the integrated circuit of the device.
  • the interconnection element of the invention may be fabricated on or independent of the electronic component to which it is joined.
  • the invention contemplates that the interconnection element or elements can be fabricated with a shape, size, and metallurgy that are not limited by the materials and layout considerations associated with the manufacture of the electronic component. Independent fabrication also avoids the exposure of the electronic component to the process conditions associated with forming the interconnection element.
  • the invention contemplates that the interconnection elements can be formed directly on contacts or terminals on the substrate, thus reducing transferring operations and reducing alignment issues .
  • the interconnection elements of the invention are designed to accommodate contact pads or terminals of electronic components having very small pitch or spacing tolerances.
  • the interconnection elements of the invention adopt alternating orientation (e.g., left-right-left-right) so as to achieve a greater pitch between their post portions than between their tip portions.
  • the interconnection elements of the invention adopt alternating lengths (e.g., short-long-short-long) so as to achieve a greater pitch between a post or anchor portion than at the tip portion of adjacent interconnection elements.
  • alternating interconnection elements can be fabricated to have a greater pitch at their tip portions than their post or anchor portions.
  • the interconnection elements, whether fabricated on or independent of the electronic component to which they are joined may adopt a variety of orientations to accommodate various configurations associated with the electronic components to which they contact.
  • Figure 1 shows a cross-sectional side view of electronic component or structure 100.
  • Structure 100 is, for example, a space transformer of a probe card assembly or an integrated circuit.
  • Structure 100 includes, in this example, semiconductor-, organic-, metal-, or ceramic-based substrate 110 having contact pads or terminals 120 on a surface of substrate 110.
  • a commercially available ceramic-based electronic component e.g., a multi-layer ceramic substrate such as a low-temperature, co-fired ceramic (LTCC) substrate
  • structure 100 may contain corresponding contact pads or terminals 121 on opposing surfaces of substrate 110.
  • LTCC low-temperature, co-fired ceramic
  • Corresponding contact pads or terminals 121 on opposing surfaces are connected, for example, through conductive circuit 119 running through substrate 110 such as, for example, a circuit of molybdenum, copper, gold, nickel, or tungsten and aluminum or combination of these materials or their alloys or other conductive element and its alloys. Details of materials, thickness, processing variations and the like can be found in co-pending, commonly-owned U.S. Patent Application No. 09/032,473, filed February 26, 1998, titled “Lithographically Defined Microelectronic Contact Structures" (FFI-P048), and PCT equivalent published as W098/52224 on November 9, 1998, both of which are incorporated herein by reference.
  • conductive circuit 119 running through substrate 110 such as, for example, a circuit of molybdenum, copper, gold, nickel, or tungsten and aluminum or combination of these materials or their alloys or other conductive element and its alloys.
  • Contact pads or terminals 120 on substrate 110 are, for example, copper, nickel, and gold that may be suitable for connecting to an interconnection element formed to the deposition of a conductive material by, for example, sputtering, electroplating or soldering.
  • the copper facilitates the electroplating process and is the upper layer.
  • overlying substrate 110 of structure 100 is shorting layer 130.
  • Shorting layer 130 is, for example, a copper (Cu) , titanium (Ti) or titanium-tungsten (Ti-W) or other appropriate metal or alloy that serves, in one sense, to short contact pads or terminals 120 during the formation of interconnection elements on substrate 110.
  • the shorting feature of shorting layer 130 can advantageously be employed to establish an appropriate potential for an electrolytic process (e.g., an electroplating process) for fabricating interconnection elements on substrate 110.
  • an electrolytic process is one technique for forming the interconnection elements of the invention, and that other techniques may also be suitable, such as chemical or sputter deposition or electroless plating processes.
  • the operations indicated can be carried out either simultaneously or sequentially on both surfaces of substrate 110, to create a "double-sided" spring device. In this case, re-distributions and a non one-to-one relationship may exist between contact structures and/or interconnection elements on opposing surfaces .
  • shorting layer 130 is introduced to a thickness of about 3000A to 6000A, such as about 5000A over a surface of substrate 110 by, for example, sputtering.
  • One alternative may be to introduce shorting layer 130 over the opposite side of substrate 110 to short contact pads or terminals 121 that extend through substrate 110.
  • Figure 2 shows structure 100 after the deposition of first masking material layer 140 over the surface of substrate 110.
  • first masking material layer 140 is a photoresist that is spin-coated on the surface of substrate 110 and patterned as known in the art.
  • First masking material layer 140 is deposited and patterned to include openings. The openings may be located at a position that is directly over a portion of contact pads or terminals 120 or, in some cases, may be located at a position that is remote from contact pads or terminals 120. By locating openings at a position remote from the contact pads or terminals, interconnection elements can be fabricated on an electronic component with a layout that differs from that of the contact pads or terminals of the electronic component.
  • first masking material layer 140 is deposited to a thickness of approximately 15-25 microns ( ⁇ ) .
  • First masking material layer 140 is generally deposited to a thickness of the desired minimum spacing distance between the body of a subsequently-formed interconnection element and the surface of substrate 110. In the example where resiliency is desired, the thickness of first masking material layer 140 should be chosen such that potential "bottoming out" of the interconnection element is minimized.
  • first masking material layer 140 is a photoresist
  • the photoresist layer may be subjected to a re-flow or other process to slope the edges of the openings. Creating sloped edges tends to reduce the number of stress points associated with an interconnection element formed through the openings.
  • a re-flow process also introduces additional cross-linking in the photoresist which strengthens the photoresist to improve its properties for subsequent processing operations. In one example, the re-flow is accomplished in stages.
  • structure 100 is brought to a temperature of approximately 105°C then ramped to 110°C and then ramped and retained for one hour at 120°C.
  • the temperature is increased to 130°C for another hour. It is to be appreciated that the temperature of the re-flow process can be adjusted higher or lower to adapt to subsequent process operations.
  • One alternative to a re-flow process is to slope the edges of the openings in first masking material layer 140 with a sputter or chemical etch.
  • FIG. 4 shows structure 100 after the introduction of activation layer 150.
  • activation layer 150 is introduced to activate the exposed surfaces for introduction of subsequent material by way of an electroplating process.
  • activation layer 150 is formed by sputtering a material such as chromium/titanium-tungsten/gold (Cr/TiW/Au) layers. Titanium/gold (Ti/Au) or chromium/gold (Cr/Au) may also be utilized.
  • An alternative to activating the surface structure 100 through sputter deposition is to chemically activate the surface.
  • a palladium/tin (Pd/Sn) chloride bath introduces a film on the surface of structure 100 and electroless plating of palladium (Pd) is introduced to form a conductive film.
  • Figure 5 shows structure 100 after the introduction and patterning of second masking material layer 160.
  • second masking material layer 160 defines the shape of the body of a subsequently-formed interconnection element.
  • first element material 170 is a thermally-stable layer.
  • One particular preferred material is a resilient alloy material of, for example, palladium/cobalt (Pd/Co) that generally will not change dimension upon exposure to temperatures to which it may be exposed, is generally inert, and is relatively easy to activate.
  • Other possible materials for first element material 170 include nickel, tungsten, rhodium, iron, copper, silver, and aluminum, preferably in alloy form.
  • activation layer 150 may be used as the thermally stable layer.
  • first element material 170 is introduced through an electroplating process as known in the art.
  • first element material 170 is made up of a plurality of layers, such as a first layer of a palladium/cobalt alloy and a second layer of palladium.
  • Figure 7 shows structure 100 after the introduction of second element material 180 over the superior surface of first element material 170.
  • second element material 180 includes a property such that its volume can be transformed from a first volume to a different second volume.
  • the volume transformation may be reversible or irreversible. Irreversibility may be achieved, for example, through a re- crystallization of the material.
  • Ni/Co nickel/cobalt
  • NTSA napthalene-tri-sulfonic acid
  • levelers such as 2- butyne-1, 4-diol and thiourea
  • salts such as nickel bromide and nickel chloride.
  • first element material 170 and second element material 180 are selected, in one embodiment, to control the amount of deformation (e.g., deflection) of the interconnection element structure away from the substrate.
  • second element material 180 is transformed from a first volume to a second, different volume.
  • the volume change is irreversible and the second volume is smaller or different (in an x, y, z coordinate sense) than the first volume. It has been determined that the ratio of thickness of first element material 170 to second element material 180, at least with first element material 170 of Pd/Co and second element material 180 of Ni/Co, is important for a chosen deflection.
  • Figure 21 shows the amount of deflection ( ⁇ (h 180 )) in thousandths of an inch of an interconnection element of a cantilever beam having first element material 170 of Pd/Co and a thickness of 200 micro-inches (about 5 microns) and varying thicknesses of second element material 180 of Ni/Co according to the relation:
  • ⁇ is the percentage of shrinkage
  • I is the length of the interconnection element beam
  • h 170 is the thickness of first element material 170
  • h 180 is the thickness of second element material 180.
  • the interconnection element is a rectangular beam of length of approximately 40 mils (about 1000 ⁇ m) .
  • the thickness of second element material 180 may range from approximately 125 to 250 micro- inches (about 3-6 ⁇ m) of Ni/Co to yield a deflection distance ( ⁇ 2 (h 180 )) on deformation of approximately 0.008 inches or 8 mils (about 200 ⁇ m) .
  • the ratio of first element material 170 to second element material 180 may vary between about 1.6 to 1 to about 0.8 to 1. Less of additional second element material 180 will produce less deflection in this example. Varying the amount of first element material 170 may dramatically affect the deflection distance.
  • first element material 170 thickness that allows for a range of thickness of second element material 180 alleviates some concern of the exactitude of a given deposition, since so long as the final structure is within the calculated ratio with a reasonable tolerance, a desired deflection should be realized.
  • concerns over plating thickness uniformity or optimizing a thickness of an electroplated structure such as by chemical-mechanical or mechanical polish
  • a polish may be suitable provided such polish is compatible with the scale of the optimization, e.g., polishing a few micro-inches (less than 1 ⁇ m) .
  • first element material 170 comprises a Pd/Co alloy and second element material 180, a Ni/Co alloy overlying first element material 170.
  • first element material 170 may constitute Ni/Co alloy and second element material 180 Pd/Co alloy.
  • first and second element materials 170 and 180 are introduced such that stress varies through the composite beam element 185, with the stress becoming increasingly tensile in the direction away from the substrate.
  • first element material 170 comprises a Ni/Co alloy that when introduced has a stress that ranges from tensile to compressive.
  • additives such as saccharin
  • Second element material 180 comprises a Pd/Co alloy that when introduced has a stress that is more tensile than that of first element 170. Sufficient tensile stress is inherent in a plated Pd/Co alloy but additional stress may be introduced through additives as known in the art.
  • first element material 170 is compressive and the stress in second element material 180 is tensile.
  • Amounts of first element material 170 and second element material 180 on the order of approximately 0.04 to 20 mils (about 1 to 500 ⁇ m) are suitable. Suitable thickness ratios may be experimentally determined.
  • first element material 170 and second element material 180 Following the introduction and patterning of first element material 170 and second element material 180, structure 100 is heated, in one example, to 40°-100°C for a period of time sufficient to relax first element material 170 of a Ni/Co.
  • the moderate heating of Ni/Co causes the material to, it is believed, creep to a more relaxed form. Creep in a material is defined generally as the time-dependent part of strain resulting from stress.
  • first element material 170 creeps under the tensile stress exerted by second element material 180. This causes interconnection element 185 to deform (e.g., deflect away from the surface of substrate 110) and reduces the magnitude of the stress in the first and second element materials 170 and 180.
  • stress relaxation can be considered the driving force for the deformation.
  • Figure 8 shows structure 100 after the removal of second masking material layer 160.
  • the removal of second masking material layer 160 may be accomplished with an oxygen plasma etch (e.g., oxygen ashing).
  • Other methods of removing second masking material layer 160 include, but are not limited to, laser ablation and wet chemical etching.
  • activation layer 150 is removed in those areas previously protected by second masking material layer 160.
  • Activation layer 150 may be removed, for example, by a chemical or sputter etch as known in the art.
  • Figure 9 shows structure 100 after the removal of activation layer 150 in exposed areas.
  • Figure 10 shows structure 100 after the removal of first masking material layer 140.
  • first masking material layer 140 is a photoresist
  • first masking material layer 140 may be suitably removed by various methods including an oxygen plasma etch, laser ablation, and wet chemical etching. Once removed, Figure 10 shows substrate 110 having a plurality of interconnection elements 185 formed on a surface thereof.
  • Figure 11 shows structure 100 after subjecting the structure generally to a thermal treatment to induce a transformation of one or both of first element material 170 and second element material 180.
  • the transformation is a volume transformation of second element material 180.
  • the volume transformation proceeds, in one embodiment, to at least 90 percent completion and preferably 90-95 percent completion.
  • the volume transformation of second element material 180 may be estimated by determining the linear coefficient of thermal expansion of the material.
  • a second element material of nickel/cobalt deposited to a thickness of about 125 to 175 micro-inches (about 3-4 ⁇ m) will experience a linear change of about 0.2 percent upon heat treatment at 310°C for ten minutes.
  • Such linear change causes the volume to shrink while the volume of first element material 170, in one embodiment, remains relatively constant.
  • the volume change causes the free end of the interconnection element to bend toward its secured base.
  • a suitable curvature measured by a distance, h., from the surface of substrate 110 is, for example, approximately 6 to 8 mils (150-200 ⁇ m) .
  • the volume transformation of second element material 180 will modify the shape of interconnection element 185.
  • the volume transformation of second element material 180 with the free end of interconnection element 185 tending to curve towards its base will similarly deform first element material 170 and activation layer 150 of interconnection element 185.
  • second element material 180 it may be desirable to limit the amount of curvature of second element material 180. Nevertheless, in one embodiment, it is desirable to achieve greater than or equal to 90 percent transformation or approximately 90-95 percent transformation to, for example, form a reliable interconnection element, e.g., reliable in the sense of deformation characteristics. In such cases, a curvature stop may be imposed over structure 100. Referring to Figure 11, once interconnection element 185 curves away from substrate
  • curvature stop 187 shown in ghost lines
  • materials may be chosen having volume transformation properties much greater than might otherwise be chosen in the absence of curvature stop 187.
  • the materials e.g., first element material 170 and second element material 180
  • the materials may be chosen of a type and amount such that the inherent deflection distance on, for example, thermal transformation is greater than 8 mils (e.g., 10-12 mils (about 250-300 ⁇ m) )
  • Curvature stop 187 such as planar substrate may be placed at a distance of about 8 mils (about 200 ⁇ m) from the surface of substrate 110 to limit the deflection distance of the interconnection elements during transformation.
  • the interconnection elements may still deform in x- and y- coordinate planes.
  • the final interconnection elements will consistently have a height of about 8 mils (about 200 ⁇ m) from the surface of substrate 110.
  • the discussion has focused on a second element material that overlies a first element material and undergoes a transformation to transform to a smaller volume or to a different stress level and cause the free end of the interconnection element to curve away from the substrate.
  • the second element material may underlie the first element material and have a property such that thermal transformation of the second element material will increase the volume of the material. In such case, similar curvature of the interconnection away from the substrate should be achieved.
  • a first element material may be selected such that it undergoes a volume transformation compared with a second element material having a relatively constant volume.
  • Other configurations such as where both materials undergo a volume transformation or have different thermal expansion properties will behave similarly as will shape memory alloys (SMAs) .
  • SMAs shape memory alloys
  • Figure 12 shows structure 100 after the deposition of third masking material layer 190 conformally over substrate 110.
  • a suitable thickness for third masking material layer 190 is about 0.3-1.5 mils (about 8 to 30 ⁇ m) .
  • third masking material layer 190 is selected such that the conformal deposition will provide adequate masking of the entire portion of the superior surface of substrate 110 as well as coverage over interconnection element 185.
  • the structural stability of interconnection element 185 is not sufficient to sustain a masking material layer deposited, for example, by spin-coating. Additional deposition techniques known in the art can be considered for this application. CVD or PECVD (plasma enhanced CVD) may be particularly useful for deposition.
  • a positive electrophoretic resist is introduced as third masking material layer 190.
  • an electrophoretic resist is an electro-deposited photoresist in which charged particles on the order of 1000 to 2000 angstroms (A) are introduced in a uniform coating over a conductive surface.
  • a suitable positive electrophoretic resist is Electro Image ® , commercially available from PPG Industries of Pittsburgh, Pennsylvania.
  • a second alternative is applying positive photoresist by spray-on method that will not damage the composite interconnection element.
  • third masking material layer 190 is chosen, in one aspect, to have a thickness sufficient to define an additional layer substantially over the interconnection element as well as provide sufficient (in one embodiment, total) masking of interconnection element 185 such that additional interconnection materials will be introduced only onto an exposed area of interconnection element 185 and not over the surface of substrate 110 (e.g., not under interconnection element 185) .
  • Figure 13 shows structure 100 being exposed to open an area over a superior surface of the composite interconnection elements.
  • mask 200 is aligned over structure 100 having openings 210 corresponding with the superior surfaces of interconnection elements 185.
  • developing proceeds like a conventional positive photoresist.
  • third masking material layer 190 will remain in all areas except the superior surface of the interconnection element 185.
  • Figure 14 illustrates the structure after development.
  • Figure 15 shows structure 100 after the introduction of third element material 220 over interconnection element 185.
  • third element material 220 is a conductive material of, for example, a nickel alloy such as nickel-cobalt (e.g., 70 percent nickel-30 percent cobalt) possibly with an additive such as discussed in detail in co-pending, commonly- assigned U.S. Patent Application No. 09/217,589, filed December 22, 1998, titled "Method of Making a Product with Improved Material Properties by Moderate Heat Treatment of a Metal Incorporating a Dilute Additive" (FFI-P036D1) , and the corresponding PCT Application No.
  • a nickel alloy such as nickel-cobalt (e.g., 70 percent nickel-30 percent cobalt) possibly with an additive such as discussed in detail in co-pending, commonly- assigned U.S. Patent Application No. 09/217,589, filed December 22, 1998, titled "Method of Making a Product with Improved Material Properties by Moderate Heat Treatment of a Metal Incorpor
  • third element material 220 is introduced to a thickness suitable for increasing the spring constant of interconnection element 185.
  • third element material 220 is introduced to a thickness of, for example, about 1 mil (about 25 ⁇ m) to account for more than 90 percent of the body of interconnection element 185.
  • interconnection element 185 including third element material 220 define an interconnection element having a spring constant and a measurable resiliency greater than interconnection element 185 without third element material 220 (e.g., the spring constant generally depending in part on the dimensions of the interconnection element) .
  • a spring constant of about 0.2 gram-force per mil or greater is suitable. It is to be appreciated that the desired spring constant may vary according to the desired application such as spring constants between about 0.01 and 10 gram-force per mil and preferably about 0.01 and 2 gram-force per mil. These parameters are only illustrative as one skilled in the art can make very thin or very thick structures with a wide range of spring constants . It is to be appreciated that interconnection element 185 may already possess the desired spring constant, even a spring constant between about 0.01 and 10 gram-force per mil, rendering the inclusion of additional spring material unnecessary.
  • a sufficient amount of spring material such as, for example, 0.5 to 1 mil (about 12 to 25 ⁇ m) of first element material 170 may be introduced, eliminating the need to introduce more spring material at this point.
  • third element material 220 is a nickel alloy, such as nickel-cobalt
  • third element material 220 may be deposited by several deposition techniques, including but not limited to, electroplating, chemical vapor deposition, sputter deposition, and electroless plating.
  • third element material 220 is deposited through an electroplating process.
  • Third element material 220 is typically applied in the form of a commercially available electroplate solution or bath.
  • a current is applied between interconnection element 185 and an anode of an electroplating cell (not shown) . Negative charge build-up on interconnection element 185 causes metal ions in the electroplating solution to be reduced to a metallic state, coating third element material 220 on interconnection element 185.
  • Nickel or a Ni/Co alloy is generally not a good receiving surface for a plating process because of its tendency to oxidize.
  • Techniques to improve nickel's or Ni/Co alloy's receiving properties include introducing (e.g., plating) a thin layer of copper (Cu) , on the order of 10-100 micro-inches (about 3 ⁇ m) to second element material 180 immediately after the introduction of second element material 180 (e.g., prior to a significant amount of oxidation of the Ni/Co) .
  • interconnection element 185 may be placed in a bath of hydrochloric acid (HC1) , a "strike bath", to activate the surface of the Ni/Co alloy, then third element material 220 may be introduced.
  • Figure 16 shows structure 100 after the optional introduction of contact material 230 on the surface of third element material 220.
  • contact material 230 reduces the resistivity of third element material 220 and provides contact metallurgy to the interconnection structure that is formed.
  • Suitable contact materials include, but are not limited to, gold (Au) , palladium (Pd) , rhodium (Rh) , and silver (Ag) , and their alloys.
  • contact material 230 is introduced to a thickness of approximately 30 micro-inches (about 0.75 ⁇ m) to the surface of third element material 220.
  • Figure 17 shows structure 100 after removal of third masking material layer 190.
  • third masking material layer 190 is a photoresist
  • third masking material layer 190 may be removed using conventional methods, such as plasma etching (e.g., oxygen ashing), laser ablation, or wet chemical etching.
  • plasma etching e.g., oxygen ashing
  • laser ablation e.g., laser ablation
  • wet chemical etching e.g., wet chemical etching.
  • interconnection element 185 having a freestanding portion is formed on substrate 110.
  • interconnection element 185 is a composite interconnection element comprised of activation layer 150, first element material 170, second element material 180, third element material 220, and contact material 230.
  • structure 100 may be subjected to a heat treatment to improve the properties of interconnection elements 185.
  • Figure 18 shows structure 100 after the introduction of travel stop material 240 over and around the structure.
  • Travel stop material 240 is introduced to limit the travel of the composite interconnection element when making contact with, for example, a contact pad or terminal of an electronic component.
  • the height, h 2 of the tip of the composite interconnection element from the surface of substrate 110 is approximately 5-15 mils (about 250-400 ⁇ m) .
  • the desired amount of deflection for interconnection element 185 may be determined to be approximately 3 mils (about 75 ⁇ m) .
  • travel stop material 240 is deposited to a thickness of approximately 2-12 mils (about 50-300 ⁇ m) to provide a height, h 2 , of interconnection element 185 over travel stop material
  • travel stop material 240 is a non-conductive material such as a photoimageable material such as SU-8, which is a negative photoresist, commercially available from MicroChem Corporation of Newton, Massachusetts.
  • Other material for travel stop material 240 includes silicon nitride or silicon oxynitride or Probelec® from Ciba Specialty Chemicals (Basil, Switzerland, www.cibasc.com).
  • travel stop material 240 is patterned.
  • travel stop material 240 is exposed through a mask such that an area around anchor portion 112 is exposed. Because travel stop material 240 is a negative photoresist, those areas that did not receive an exposure due to the mask will be developed to remove the photoresist (and the exposed portions of the photoresist will remain) .
  • Figure 19 shows structure 100 after patterning travel stop material 240 over a portion of substrate 110 including anchor portion 112 of interconnection elements 185.
  • travel stop material 240 will allow the deflection of interconnection elements 185 towards substrate 110 with some limitation. For example, when a second electronic component is directed towards substrate 110, the electronic component will be stopped by travel stop material 240.
  • FIG 20 shows interconnection element 185 having an overcoating of contact material 250, such as electroless gold (Au) coated to a few micro-inches (about 1-10 ⁇ m) .
  • contact material 250 such as electroless gold (Au) coated to a few micro-inches (about 1-10 ⁇ m) .
  • Au electroless gold
  • coating 250 is optional in this embodiment.
  • interconnection element 185 is a composite interconnection element. It is to be appreciated that the formation of interconnection element 185 of the core of first element material 170 and second element material 180 may be sufficient for certain applications and the introduction of additional resilient material (e.g., third element material 220) is unnecessary.
  • Such an interconnection element may be defined possibly with an over-coating of contact material (e.g., Au) .
  • third element material 220 may be added beyond third element material 220 to, for example, increase the resiliency of the interconnection elements.
  • process steps similar to those described with the introduction of third element material 220 may be employed.
  • concerns of damaging the interconnection element in the application of additional masking material layer (s) are generally not as significant so more traditional forms of masking material may be utilized.
  • Figures 22-27 illustrate an additional embodiment of forming an interconnection element according to the invention, starting from the structure illustrated in Figure 6 showing first element material 170 overlying activation layer 150 patterned according to the pattern established by second masking material layer 160.
  • first element material 170 is a thermally-stable material such as a Pd/Co alloy.
  • second masking material layer 160 is removed, for example, by an oxygen plasma etch (e.g., oxygen ashing), wet chemical etching, or laser ablation.
  • FIG 23 shows structure 100 after the introduction of shape memory alloy (SMA) material 380.
  • SMAs are groups of metallic materials that demonstrate the ability to return to some previously defined shape or size when subjected to the appropriate procedure, typically a thermal procedure. Such materials can recover substantial strain or generate significant force upon changing shape. Certain nickel- titanium alloys and copper-based alloys meet this criteria. The copper-based alloys (such as copper-zinc alloys) are particularly suitable for plating operations.
  • SMA material 380 is stretched from a memory state or shape to a martinsite (low-temperature) state, i.e., in this example, the martinsite state is a stretched state.
  • SMA material 380 that is a sheet has greater dimensions, for example, in its length and width than in a memory state.
  • SMA material 380 is laminated over first element material 170 using, for example, an adhesive such as an epoxy or a eutectic method such as with a gold eutectic.
  • laminated SMA material 380 in its martinsite state is patterned, using, for example, photolithography techniques, into beams overlying patterned first element material 170.
  • first masking material layer 140 is removed by a suitable technique to reveal a plurality of interconnection elements of first element material 170 each having a beam of SMA material 380 laminated thereto, a cantilever beam of each structure separated from the surface of substrate 110 by a height, h 3 .
  • Figure 25 shows an exploded side view of a single beam of SMA material 380, having a length, a, and a thickness, t, in its martinsite or stressed state.
  • Figure 26 shows a structure after a heat treatment to, in one sense, transition SMA material 380 from its martinsite state to a high-temperature austensite phase or memory state.
  • Figure 26 includes an insert of SMA material 380 in its memory state, having a length, a', and thickness, t'. In a memory state, SMA material 380 has different dimensions than in its martinsite state.
  • the insert for Figure 26 shows SMA material 380 in its memory state having length (a' ⁇ a) and a width less than a width in a martinsite or stressed state.
  • the structure is subjected to a heat treatment at a temperature above the transition temperature of SMA material 380 for the austensite phase. Above the transition temperature, SMA material 380 will deform back towards its memory state thereby shrinking the film. Through bimorphic or bi-metallic action, the end of the composite beam of SMA material 380 and first element material 170 will, in this instance, bend toward its base. In this manner, a desired curvature of an interconnection element may be achieved, such as a height, h 4 of approximately 8 mils (about 200 ⁇ m) from the surface of substrate 110. In some instances, it may be desirable to limit the amount of curvature of the interconnection element by, for example, a curvature stop such as described above with reference to Figure 11 and the accompanying text.
  • the transition of SMA material 380 to its memory state is a thermal transformation. It is to be appreciated that it may be possible to incorporate alternative external stimuli (e.g., pressure changes or radiation) to bring about the transformation. In the case of a thermal transformation at elevated temperature, the temperature treatment that brought about such thermal transformation may be extended to anneal first element material 170 to modify the stress of the material and increase the stability of the deformed material.
  • alternative external stimuli e.g., pressure changes or radiation
  • SMA material 380 may be removed, leaving an interconnection element of first element material 170 (and activation layer 150) .
  • SMA material 380 may be removed directly by way of a plasma or chemical etch or laser ablation.
  • the adhesive may be dissolved to separate SMA material 380 from the first element material 170.
  • Figure 27 shows the resultant structure wherein SMA material 380 is removed leaving first interconnection element of first element material 170.
  • SMA material can be left on.
  • the stiffness of the SMA material will contribute to the overall spring constant, giving a spring constant which is high enough, without the addition of more material.
  • a thickness of SMA material can be selected which will deflect a relatively thick beam (material 170). Such a thick beam can be conditioned to retain this new shape and the SMA material can be removed, such that the resulting structure will have a sufficiently high spring constant.
  • Figure 28 shows one final structure formed according to this embodiment.
  • the structure is similar to Figure 20, and shows a cross-sectional side view of three interconnection elements formed on the surface of substrate 110.
  • Each interconnection element includes first element material 170 and third element material 220 of, for example, a nickel alloy such Ni/Co (e.g., 70 percent Ni-30 percent Co), possibly with an additive, that provides increased spring force to the interconnection element (i.e., a "spring material").
  • third element material 220 is introduced to a thickness suitable for increasing the spring constant of the interconnection element to a suitable level. Thicknesses on the order of about 1 mil (about 25 ⁇ m) which accounts for more than 90 percent of the body of the interconnection element are suitable according to current technology.
  • Figure 28 also shows optional contact material 230 of, for example, gold (Au) , palladium (Pd) , rhodium (Rh) , and silver (Ag) , and their alloys introduced to a thickness of approximately 30 micro- inches (about 0.75 ⁇ m) . Also shown in this illustration is optional contact material 250, such as electroless gold (Au) coated to a few micro-inches (about 1-10 ⁇ m) . Finally, Figure 28 shows optional travel stop material 240 that may be used to, in one instance, limit the deflection of the interconnection element. The introduction of each of these materials is similar to that described above with reference to Figures 12-20 and the accompanying text. The preceding description illustrates, among other aspects, interconnection elements and the fabrication of interconnection elements with a desired shape and spring constant. The fabrication techniques take advantage of the behavior of certain metallic materials with transformable properties to deform in response to an external stimulus
  • interconnection elements described herein are suitable for many uses including, but not limited to employment with an electronic component to make temporary or permanent contact, or temporary and then permanent contact to the electronic component. Such contact may be utilized in manufacturing flows in, for example, the formation of integrated circuit chips or dies.
  • the interconnection elements of the invention may form temporary contacts to bond pads of a singulated or unsingulated chip or die as part of "burn-in" and/or functional testing of the chip or die to link the chip or die to a testing device.
  • An example of a permanent connection is the use of the interconnection elements of the invention, possibly including the interconnection elements utilized to make temporary connection while testing a chip or die, to electrically link the chip or die to external system components (e.g., a PCB) through, for example, a package.
  • external system components e.g., a PCB
  • interconnection elements of the invention may be utilized in testing equipment such as extending as probes from a substrate, such as a probe card or a space transformer of a probe card for testing electronic components as described in U.S. Patent No.
  • U.S. Patent No. 5,829,128 further describes interconnection elements connected directly to a semiconductor die (e.g., to bond pads) eliminating the need for a corresponding package.
  • the interconnection elements described herein are likewise suitable for such an application.
  • One example is interconnection elements coupled to a first substrate are coupled, for example, through pressure connections, to corresponding ones of contact nodes on a second substrate (e.g., a support substrate).
  • the second contact nodes include external connection points to couple the collective assembly (e.g., first and second substrates) to corresponding third contact nodes on a third substrate such as a circuit board.

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  • Engineering & Computer Science (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Manufacturing & Machinery (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • Measuring Leads Or Probes (AREA)
  • Testing Or Measuring Of Semiconductors Or The Like (AREA)
  • Electric Connection Of Electric Components To Printed Circuits (AREA)
  • Battery Mounting, Suspending (AREA)
  • Connecting Device With Holders (AREA)

Abstract

L'invention concerne un élément d'interconnexion ainsi qu'un procédé de fabrication et d'utilisation d'un élément d'interconnexion comprenant un premier matériau destiné à être couplé à un substrat et un deuxième matériau constitué d'un matériau à propriété transformable, de sorte que lors de la transformation, la forme de l'interconnexion soit modifiée. Par exemple, on peut utiliser un matériau transformable, de manière que le volume des premier et/ou deuxième matériaux puisse subir une transformation thermique et change (par exemple, diminue).
EP01922806A 2000-04-12 2001-03-28 Ressorts faconnes et leurs procedes de fabrication et d'utilisation Withdrawn EP1275150A2 (fr)

Applications Claiming Priority (5)

Application Number Priority Date Filing Date Title
US09/547,560 US6640432B1 (en) 2000-04-12 2000-04-12 Method of fabricating shaped springs
US547561 2000-04-12
US547560 2000-04-12
US09/547,561 US7458816B1 (en) 2000-04-12 2000-04-12 Shaped spring
PCT/US2001/009994 WO2001080315A2 (fr) 2000-04-12 2001-03-28 Ressorts faconnes et leurs procedes de fabrication et d'utilisation

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Publication Number Publication Date
EP1275150A2 true EP1275150A2 (fr) 2003-01-15

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EP (1) EP1275150A2 (fr)
JP (1) JP2003531495A (fr)
KR (2) KR100835027B1 (fr)
CN (1) CN100339985C (fr)
AU (1) AU2001249567A1 (fr)
TW (1) TW546803B (fr)
WO (1) WO2001080315A2 (fr)

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KR20020026585A (ko) * 2000-06-20 2002-04-10 나노넥서스, 인코포레이티드 집적회로를 테스트하고 패키지하기 위한 시스템
KR100941360B1 (ko) * 2006-07-21 2010-02-11 가부시키가이샤후지쿠라 집적 회로 소켓, 집적 회로 소켓 조립체, 및 집적 회로 소켓의 제조 방법
ATE503037T1 (de) * 2008-10-17 2011-04-15 Atotech Deutschland Gmbh Spannungsreduzierte ni-p/pd-stapel für waferoberfläche
US8476749B2 (en) * 2009-07-22 2013-07-02 Oracle America, Inc. High-bandwidth ramp-stack chip package
US8441808B2 (en) * 2010-09-22 2013-05-14 Palo Alto Research Center Incorporated Interposer with microspring contacts
TWI449280B (zh) * 2011-01-17 2014-08-11 Hon Hai Prec Ind Co Ltd 測試連接器
KR101738421B1 (ko) 2015-11-10 2017-05-23 광주과학기술원 자가변형 플렉서블 필름 및 이의 제조 방법
KR102042052B1 (ko) * 2017-03-23 2019-11-08 광주과학기술원 자가변형 플렉서블 필름 및 이의 제조 방법
KR102114210B1 (ko) * 2018-12-17 2020-05-25 주식회사 코리아 인스트루먼트 프로브 빔 및 프로브 모듈
CN114108041A (zh) * 2021-12-20 2022-03-01 太仓市惠得利弹簧有限公司 一种弹簧表面抗氧化处理工艺

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CN100339985C (zh) 2007-09-26
AU2001249567A1 (en) 2001-10-30
JP2003531495A (ja) 2003-10-21
KR20020090234A (ko) 2002-11-30
TW546803B (en) 2003-08-11
KR20070093456A (ko) 2007-09-18
WO2001080315A2 (fr) 2001-10-25
CN1451179A (zh) 2003-10-22
KR100835027B1 (ko) 2008-06-03
KR100801353B1 (ko) 2008-02-05
WO2001080315A3 (fr) 2002-03-28

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