SPECIFICATION

Title: Probes with Planar Unbiased Spring Elements for Electronic Component Contact

FIELD OF THE PRESENTDISCLOSURE

[0001] Embodiments of the present disclosure relate to microprobes (e.g., for use in the wafer level testing or socket testing of integrated circuits, or for use in making electrical connections to PCBs or other electronic components) and mote particularly to pin-like microprobes (i.e., microprobes that have vertical or longitudinal heights that are much greater than their widths) wherein spring elements have planar configurations when in an unbiased state. In some embodiments, the microprobes are produced, at least in part, by electrochemical fabrication methods and more particularly by multi-layer, multi-material electrochemical fabrication methods.

BACKGROUND OF THE PRESENT DISCLOSURE

Probes:

[0002] Numerous electrical contact probe and pin configurations have been commercially used or proposed, some of which may qualify as prior art and others of which do not qualify as prior art. Electrochemical Fabrication:

[0003] Electrochemical fabrication techniques for forming three-dimensional structures from a plurality of adhered layers have been, or are being, commercially pursued by Microfabrica® Inc. (formerly MEMGen Corporation) of VanNuys, California under the process names EFAB™ and MICA FREEFORM®.

[0004] Various electrochemical fabrication techniques and methods for forming microstructures using electrochemical fabrication techniques are known.

[0005] Electrochemical fabrication provides the ability to form prototypes and commercial quantities of miniature objects, parts, structures, devices, and the like at reasonable costs and in reasonable times. In fact, electrochemical fabrication is an enabler for the formation of many structures that were hitherto impossible to produce. Electrochemical fabrication opens the spectrum for new designs and products in many industrial fields. Even though electrochemical fabrication offers this new capability, and it is understood that electrochemical fabrication techniques can be combined with designs and structures known within various fields to produce new structures, certain uses for electrochemical fabrication provide designs, structures, capabilities and/or features not known or obvious in view of the state of the art.

[0006] A need exists in various fields for miniature devices having improved characteristics, reduced fabrication times, reduced fabrication costs, simplified fabrication processes, greater versatility in device design, improved selection of materials, improved material properties, more cost effective and less risky production of such devices, and/or more independence between PCT Application Attorney Docket No. 202718-201001/WO(MFT027CWO) geometric configuration and the selected fabrication process.

SUMMARY OF THE PRESENT DISCLOSURE

[0007] It is an object of some embodiments of the present disclosure to provide improved probes that include compliant elements formed from a plurality of compliant modules that include planar but non-linear (i.e., not straight) springs (when unbiased) where the planes of the springs are perpendicular to a longitudinal axis of the probes and provide for compliance along the longitudinal axis of the probes wherein the compliant modules are stacked in a serial manner. [0008] It is an object of some embodiments of the present disclosure to provide an improved method of forming probes.

[0009] It is an object of some embodiments of the present disclosure to use individual compliant modules as probes with a single contact tip.

[0010] It is an object of some embodiments of the present disclosure to use individual compliant modules as probes with two oppositely facing contact tips.

[0011] It is an object of some embodiments of the present disclosure to provide two or more compliant modules with reversed orientations to provide probes with two oppositely oriented contact surfaces or tips.

[0012] It is an object of some embodiments of the present disclosure to provide probes and/or compliant modules with base features for engaging array structures or engage tips of other compliant modules.

[0013] It is an object of some embodiments of the present disclosure to provide probes and/or compliant modules with tip features for engaging tips or base structures of other compliant modules.

[0014] It is an object of some embodiments of the present disclosure to provide array structures (e.g., guide plates, mounting bases, or the like) with features for engaging probes. [0015] It is an object of some embodiments of the present disclosure to provide probes and/or modules with structures with features for engaging array structures (e.g., guide plates, mounting bases, or the like).

[0016] It is an object of some embodiments of the present disclosure to provide probe arrays with compliant modules extending from one surface of an array structure (e.g., an array substrate).

[0017] It is an object of some embodiments of the present disclosure to provide probe arrays with compliant modules extending from an upper surface and from a lower surface of an array. [0018] It is an object of some embodiments to provide dielectric array structures with at least one surface (e.g., an upper surface, a lower surface) or both an upper surface and a lower surface configured for receiving compliant modules. PCT Application Attorney Docket No. 202718-201001/WO(MFT027CWO)

[0019] It is an object of some embodiments to provide a dielectric array structure that includes at least one surface with electrically conductive regions for engaging compliant modules (e.g., a top surface, a bottom surface, or both surfaces having electrical contact or connection regions for engaging probes and/or having traces that electrically connect probes to one another or that provide connections between individual probes and other circuit elements).

[0020] It is an object of some embodiments to provide a conductive array structure that includes at least one surface with dielectric regions for providing electrical isolation of compliant modules (e.g., dielectric regions located on a top surface, a bottom surface, or both surfaces).

[0021] It is an object of some embodiments to provide an array structure with electrically conductive paths that extend from one side of the structure to another side of the structure wherein at least one or more conductive paths are isolated from one or more other conductive paths.

[0022] It is an object of some embodiments of the present disclosure to provide array structures with recesses or raised features for engaging compliant modules without regard to rotational orientation about a longitudinal axis of the module, only with regard to selected longitudinal orientations, or with regard to a single longitudinal orientation.

[0023] It is an object of some embodiments of the present disclosure to provide array structures with through holes configured for accepting inserted probes or compliant modules, for retaining probes or compliant modules by limiting extent of insertion from at least one direction based, at least in part, on at least one feature of the array structure.

[0024] It is an object of some embodiments of the present disclosure to provide probes or compliant modules with features for engaging through holes in array structures such that the probes or the compliant modules are retained by limiting extent of insertion from at least one direction based, at least in part, on one or more features of the probes or compliant modules. [0025] It is an object of some embodiments of the present disclosure to provide methods for making probe arrays that include multiple probes formed from stacked compliant modules.

[0026] It is an object of some embodiments of the present disclosure to provide methods for making probe arrays that include probes formed from single compliant modules.

[0027] It is an object of some embodiments of the present disclosure to provide methods for making probe arrays that include probes formed from pairs of back-to-back compliant modules that may or may not share a common base or that may not include a base at all.

[0028] Other objects and advantages of various embodiments of the present disclosure will be apparent to those of skill in the art upon review of the teachings herein. The various embodiments of the present disclosure, set forth explicitly herein or otherwise ascertained from the teachings herein, may address one or more of the above objects alone or in combination, or PCT Application Attorney Docket No. 202718-201001/WO(MFT027CWO) alternatively may address some other object ascertained from the teachings herein. It is not necessarily intended that all objects be addressed by any single aspect of the present disclosure even though that may be the case regarding some aspects.

[0029] In a first aspect of the invention, a probe for making contact between two electronic circuit elements, includes: (i) at least one standoff having a proximal end and a distal end; (ii) at least one first compliant element that has a non-linear planar configuration when not biased and that provides compliance in a direction perpendicular to the planar configuration of the first compliant element, wherein a first portion of the first compliant element functionally joins the standoff at a location closer to the proximal end than the distal end and a second portion of the first compliant element functionally joins a first tip that can compliantly move relative to the standoff, wherein the first tip extends longitudinally beyond a proximal end of the standoff when the compliant element is not biased; and (iii) at least one second compliant element that provides compliance in a direction perpendicular to the planar configuration of the first compliant element, wherein a first portion of the second compliant element functionally joins the standoff at a location closer to the distal end than the proximal end and a second portion of the second compliant element functionally joins a second tip that can compliantly move wherein the second tip extends longitudinally beyond the distal end of the standoff when the second compliant element is not biased, wherein the first and second compliant elements are spaced from one another along at least a portion of a longitudinal length of the standoff and undergo opposite longitudinal changes when the first and second tips are compressed.

[0030] Numerous variations of the first aspect exist and include, for example: (1) the second compliant element may have a non-linear planar configuration (i.e. is not a straight beam) when not biased and providing compliance in a direction substantially perpendicular to the planar configuration of both the first and second compliant elements; (2) the first compliant element may include at least two longitudinally spaced compliant elements which are functionally joined to the first module tip such that they move together upon longitudinal compression of the first module tip toward the second module tip and the second compliant element may include at least two longitudinally spaced compliant elements which are functionally joined to the second module tip such that they move together upon longitudinal compression of the second module tip toward the first module tip; (3) the first compliant element may couple to the standoff at the proximal end of the standoff, and the second compliant element may have a surface that joins the proximal end of the standoff; (4) the standoff may include a laterally extended structure at an intermediate longitudinal position between the first and second compliant elements that provides a stop structure that inhibits excessive longitudinal motion of at least one of the first and second compliant elements (e.g. motion that might exceed the elastic range of motion of one of the PCT Application Attorney Docket No. 202718-201001/WO(MFT027CWO) compliant elements) upon compression; (5) the first compliant element may include at least two co-planar spring elements that are intertwined and each is attached to the first tip and each is attached to a separate standoff; (6) the separate standoffs may be functionally joined to one another via the base; (7) the first compliant element may include at least two longitudinally spaced compliant elements which are functionally joined to the first tip such that they move together upon longitudinal compression of the first tip toward the second tip; (8) the longitudinally spaced compliant elements of the first compliant element may have a rotational orientation selected from the group consisting of: (i) a same rotational orientation, and (ii) opposite rotational orientations; (9) the at least two co-planar spring elements may include at least three co-planar spring elements; (10) the first compliant element may include at least two co-planar spring elements that are intertwined and each is attached to the first module tip and each is attached to a separate standoff; and (11) a combination of two or more of the prior variations, mutatis mutandis, to the extent the combination does not eliminate the functionality of the probe.

[0031] In a second aspect of the invention, a probe module includes: (i) a base; (ii) at least one standoff connected to the base; and (iii) at least one compliant element that has a planar configuration, when not biased, that provides a compliance in a direction perpendicular to the planar configuration, wherein the first compliant element comprises at least two co-planar spring elements that are intertwined with each other having a first portion that functionally couples to the at least one standoff and a second portion that functionally couples to a common first tip, wherein the common first tip can compliantly move relative to the first base and wherein the common first tip extends beyond a height of the at least one first standoff when the first compliant element is not biased.

[0032] Numerous variations of the first aspect exist and include, for example: (1) the at least two co-planar springs may each have an inward rotating spiral configuration that couples the at least one first standoff to the common first tip wherein the spiral has a configuration selected from the group consisting of: (i) a circular spiral, (ii) a rectangular spiral, (iii) a hexagonal spiral, (iv) an octagonal spiral, (v) a counterclockwise rotating inward spiral, (vi) a clockwise inward rotating spiral, and (vii) a spiral having a radially extending connection to the common first tip; (2) the spiral may have a rotational extent selected from the group consisting of: (i) at least 180°, (ii) at least 360°, (iii) at least 540°, and (iv) at least 720°; (3) the base may include a first portion and a second portion, the first portion having at least one transversal size that is different than a corresponding transversal size of the second portion; (4) the base may additionally include a base second tip that points in a direction opposite to that of the common first tip; (5) the probe module may further include a down-facing extension that is configures for acting as a movement stop in PCT Application Attorney Docket No. 202718-201001/WO(MFT027CWO) the event that an excessive compression force is applied between the common first tip and the base; (6) the at least one compliant element may further include a protruding stop structure that extends from the base toward the at least one compliant element such that a lower portion of the common first tip will be engaged by the protruding stop structure, in the event that an excessive compression force is applied between the common first tip and the base; (7) the at least one compliant element may include at least two co-planar spring elements that are intertwined and each is attached to the common first tip and each is attached to a separate standoff; (8) the separate standoffs may be functionally joined to one another via the base; and (9) a combination of two or more of the prior variations, mutatis mutandis, to the extent the combination does not eliminate the functionality of the probe module.

[0033] Other aspects of the present disclosure will be understood by those of skill in the art upon review of the teachings herein. Other aspects of the present disclosure may involve combinations of the above noted aspects. These other aspects of the present disclosure may provide various combinations of the aspects presented above as well as provide other configurations, structures, functional relationships, and processes that have not been specifically set forth above but are taught by other specific teachings set forth herein, by the teachings of the specification as a whole, or by known teachings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0034] FIGS. 1A - IF schematically depict the formation of a first layer of a structure using adhered mask plating where the blanket deposition of a second material overlays both the openings between deposition locations of a first material and the first material itself.

[0035] FIG. 1G depicts the completion of formation of the first layer resulting from planarizing the deposited materials to a desired level.

[0036] FIGS. 1H and II respectively depict the state of the process after formation of the multiple layers of the structure and after release of the structure from the sacrificial material. [0037] FIG. 2 depicts an isometric view of an example spring module or compliant module having two connected spring elements, a base, and a connecting support that may be used in a probe or as a probe.

[0038] FIG. 3 depicts an isometric view of a second example spring module or compliant module that may be used in a probe, or as a probe, similar to the module of FIG. 2 with the exception that the two spring elements are thicker and, as such, provide a greater spring constant than that of the elements of FIG. 2.

[0039] FIG. 4 depicts a partially cut view of a probe including a plurality of spring modules and a sheath.

[0040] FIGS. 5A-5B, 6A-6B, 7A-7C, and 8-10 provide side views of spring modules or PCT Application Attorney Docket No. 202718-201001/WO(MFT027CWO) compliant modules similar to those of FIGS. 2 and 3 or cut views through planar spring elements of such modules.

[0041] FIGS. 11 - 13 provide pairs of modules that share a common base with one of the modules oriented upward and the other oriented downward such that two oppositely oriented contact tips are provided along with two independently operable pairs of compliant elements. [0042] FIG. 14 illustrates a side view of three probes at different stages of mounting to an array plate.

[0043] FIG. 15 is similar to that of FIG. 14 with the exception that the array structure is provided with recesses for receiving probe modules.

[0044] FIG. 16 provides a side view showing the loading of a plurality of probes like those of FIG. 8 into an array structure plate having through holes.

[0045] FIG. 17 provides a side view showing the loading of a plurality of probes like those of FIG. 9 into an array structure having through holes.

[0046] FIG. 18A provides a top view of the upper surface of an example three-by-three array structure plate with circular through holes.

[0047] FIG. 18B provides a cut view of the array structure plate of FIG. 18 A along line 18B/18C - 18B/18C along with probes being loaded into the three openings at different stages of loading.

[0048] FIG. 18C shows a similar view to that of FIG. 18B with the three probes loaded into their respective openings and with the lower portion of the probe bases providing lateral alignment and the upper portion of the bases providing a lip which engages the upper surface of the array structure to provide longitudinal alignment.

[0049] FIG. 18D provides a side cut view of a probe along with three example layer configurations (Examples A, B, and C) that may be used in forming the probe of FIG. 12.

[0050] FIG. 19 provides a side view of a spring module similar to those of some of the previous embodiments, with the exception that the module includes not only a first upward facing tip attached to the compliant elements but also a downward facing tip attached to a lower surface of the base of the module.

[0051] FIG. 20 provides a side view of a module according to another embodiment of the present disclosure.

[0052] FIGS. 21 A - 21C provide different views of a module according to another embodiment of present disclosure.

[0053] FIGS. 22A - 22C provide three similar views to those shown in FIGS. 21 A - 21C for another embodiment of the present disclosure.

[0054] FIGS. 23 A - 23B provide a side view of a module and a side view of the module PCT Application Attorney Docket No. 202718-201001/WO(MFT027CWO) engaging another module, respectively.

[0055] FIG. 24 provides a side view of a module according to another embodiment of the present disclosure.

[0056] FIGS. 25A - 25B provide a side view and a cut view of a module according to another embodiment of the present disclosure.

[0057] FIG. 26 provides a side view of module with a single spring element supporting a tip. [0058] FIG. 27 provides a side view of module with a single spring element supporting a tip.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS Electrochemical Fabrication in General

[0059] FIGS. 1 A - II illustrate side views of various states in an alternative multi-layer, multi-material electrochemical fabrication process. FIGS. 1A - 1G illustrate various stages in the formation of a single layer of a multi-layer fabrication process where a second metal is deposited on a first metal as well as in openings in the first metal so that the first and second metal form part of the layer. In FIG. 1 A, a side view of a substrate 82 having a surface 88 is shown, onto which pattemable photoresist 84 is cast as shown in FIG. IB. In FIG. 1C, a pattern of resist is shown that results from the curing, exposing, and developing of the resist. The patterning of the photoresist 84 results in openings or apertures 92(a) - 92(c) extending from a surface 86 of the photoresist through the thickness of the photoresist to surface 88 of the substrate 82. In FIG. ID, a metal 94 (e.g., nickel) is shown as having been electroplated into the openings 92(a) - 92(c). In FIG. IE, the photoresist has been removed (i.e., chemically or otherwise stripped) from the substrate to expose regions of the substrate 82 which are not covered with the first metal 94. In FIG. IF, a second metal 96 (e.g., silver) is shown as having been blanket electroplated over the entire exposed portions of the substrate 82 (which is conductive) and over the first metal 94 (which is also conductive). FIG. 1G depicts the completed first layer of the structure which has resulted from the planarization of the first and second metals down to a height that exposes the first metal and sets a thickness for the first layer. In FIG. 1H, the result of repeating the process steps shown in FIGS. IB - 1G several times to form a multi-layer structure is shown where each layer consists of two materials. For most applications, one of these materials is removed, as shown in FIG. II, to yield a desired 3-D structure 98 (e.g., component or device) or multiple such structures.

[0060] Various embodiments of various aspects of the present disclosure are directed to formation of three-dimensional structures from materials, some, or all, of which may be electrodeposited or electroless deposited (as illustrated in FIGS. 1 A - II). Some of these structures may be formed from a single build level formed from one or more deposited materials while others are formed from a plurality of build layers, each including at least two materials PCT Application Attorney Docket No. 202718-201001/WO(MFT027CWO)

(e.g., two or more layers, more preferably five or more layers, and most preferably ten or more layers). In some embodiments, layer thicknesses may be as small as one micron or as large as fifty microns. In other embodiments, thinner layers may be used while in other embodiments, thicker layers may be used. In some embodiments, microscale structures have lateral features positioned with 0.1 - 10 micron level precision and minimum feature sizes on the order of microns to tens of microns. In other embodiments, structures with less precise feature placement and/or larger minimum features may be formed. In still other embodiments, higher precision and smaller minimum feature sizes may be desirable. In the present application, mesoscale and millimeter-scale have the same meaning and refer to devices that may have one or more dimensions that may extend into the 0.5 - 50 millimeter range, or larger, and features positioned with a precision in the micron to 100 micron range and with minimum feature sizes on the order of tens of microns to hundreds of microns.

[0061] The various embodiments, alternatives, and techniques disclosed herein may form multi-layer structures using a single patterning technique on all layers or using different patterning techniques on different layers. For example, various embodiments of the present disclosure may perform selective patterning operations using conformable contact masks and masking operations (i.e. operations that use masks which are contacted to but not adhered to a substrate), proximity masks and masking operations (i.e. operations that use masks that at least partially selectively shield a substrate by their proximity to the substrate even if contact is not made), non-conformable masks and masking operations (i.e. masks and operations based on masks whose contact surfaces are not significantly conformable), and/or adhered masks and masking operations (masks and operations that use masks that are adhered to a substrate onto which selective deposition or etching is to occur as opposed to only being contacted to it). Conformable contact masks, proximity masks, and non-conformable contact masks share the property that they are preformed and brought to, or in proximity to, a surface which is to be treated (i.e. the exposed portions of the surface are to be treated). These masks can generally be removed without damaging the mask or the surface that received treatment to which they were contacted or located in proximity to. Adhered masks are generally formed on the surface to be treated (i.e. the portion of that surface that is to be masked) and bonded to that surface such that they cannot be separated from that surface without being completely destroyed or damaged beyond any point of reuse. Adhered masks may be formed in a number of ways including: (1) by application of a photoresist, selective exposure of the photoresist, and then development of the photoresist, (2) selective transfer of pre-patterned masking material, and/or (3) direct formation of masks from computer-controlled depositions of material. In some embodiments, adhered mask material may be used as a sacrificial for the layer or may be used only as a masking PCT Application Attorney Docket No. 202718-201001/WO(MFT027CWO) material which is replaced by another material (e.g., dielectric or conductive material) prior to completing formation of a layer where the replacement material will be considered the sacrificial material of the respective layer. Masking material may or may not be planarized before or after deposition of material into voids or openings included therein.

[0062] Patterning operations may be used in selectively depositing material and/or may be used in the selective etching of material. Selectively etched regions may be selectively filled in or filled in via blanket deposition, or the like, with a different desired material. In some embodiments, the layer-by-layer build up may involve the simultaneous formation of portions of multiple layers. In some embodiments, depositions made in association with some layer levels may result in depositions to regions associated with other layer levels (i.e., regions that lie within the top and bottom boundary levels that define a different layer’s geometric configuration).

[0063] Temporary substrates on which structures may be formed may be of the sacrificial- type (i.e. destroyed or damaged during separation of deposited materials to the extent they cannot be reused) or non-sacrificial-type (i.e. not destroyed or excessively damaged, i.e. not damaged to the extent they may not be reused, e.g. with a sacrificial or release layer located between the substrate and the initial layers of a structure that is formed). Non-sacrificial substrates may be considered reusable, with little or no rework (e.g., by replanarizing one or more selected surfaces or applying a release layer, and the like) though they may or may not be reused for a variety of reasons.

[0064] Definitions of various terms and concepts that may be used in understanding the embodiments of the present disclosure (either for the devices themselves, certain methods for making the devices, or certain methods for using the devices) will be understood by those of skill in the art.

Probes with Planar Spring Modules:

[0065] Some embodiments of the present disclosure are directed to spring modules with each spring module including at least one centrally located tip attached to at least one planar compliant spring element (while in an unbiased state) which is in turn attached to a base via a connecting bridge wherein an axis of primary spring compliance is perpendicular to the plane of the spring arm or arms that form the spring element. Some embodiments are directed to the spring modules including compliant elements that have flat springs in the form of inward winding spirals that end in longitudinally extending contact tips or tip stand off s/arms. Some embodiments are directed to probes formed as, or from, single spring modules. Some embodiments are directed to probes formed as, or from, back-to-back spring modules that may share a common base element. Some embodiments are directed to probes formed from a plurality of spring modules in combination with other components such as probe tips (that may PCT Application Attorney Docket No. 202718-201001/WO(MFT027CWO) be separate from spring module tips), tip extensions, and sheaths. Some embodiments are directed to methods for forming spring modules; forming probes that include single spring modules, forming probes that include back-to-back spring modules, or forming probes that include a plurality of adhered or contacting spring modules built up during a process that forms and simultaneously assembles components or structures, while still others are directed to forming probe components and thereafter assembling them into working probe structures. Still other embodiments are directed to probe arrays that include one or more of the probe types noted above and array structures (e.g., substrates, guide plates, and the like). Still other embodiments are directed to methods of making such probe arrays.

[0066] Example spring modules are shown in FIGS. 2 - 3. FIG. 2 depicts an isometric view of an example spring module 200 with two undeflected spring elements 221-1 and 221-2, a base 201 spaced from the spring elements and a connecting support (or bridge) 211 that bridges a longitudinal module gap MG between the spring elements and the base. In the example of FIG. 2, each of the two spring elements take the form of a planar radially extending spiral that extends from the radially displaced bridge 211 to a centrally or axially positioned tip element 231. The springs are separated longitudinally by a gap SG. In this example, the bridge 211 connects one end of each spring element together while a tip element 231 connects the other ends of the spring elements together. The tip element 231 is formed with a desired tip height TH extending above the upper spring, each spring element is formed with a desired material, beam thickness or spring height SH, beam width or spring width SW, spacing between spring coils CS, and coiled beam length that allows the spring to deflect a desired amount without exceeding an elastic deflection limit of the structure and associated material from which it is formed while providing a desired fixed or variable spring force over its deflection range. In particular, the length of the tip may be such that a desired compression of a module tip toward the base can occur without the base, bridge, and spring elements interfering with one another. In some embodiments, for example, a maximum travel distance for the tip of each module may be as little as 5 um (um = micron) or less or as much as 500 urns (e.g., 25 urns, 50 um ,100 um or 200 um) or more. For example, in some embodiments, a maximum travel distance per module may be 25 um to 200 um while in other example embodiments, the maximum travel distance per module may be 50 um to 150 um. In some embodiments, the maximum travel distance of the tip may be set by a hard stop such as by the deflected portion of the spring or tip coming into contact with the base, a stop structure on the base, or possibly by a surface that contacts the tip (e.g., the surface of an adjacent module) coming into contact with the upper portion of the bridge. In other embodiments, the maximum travel distance may be instilled by the compliant spring or tip portion coming into contact with a soft stop or compliance decreasing structure. The force to achieve maximum deflection (or PCT Application Attorney Docket No. 202718-201001/WO(MFT027CWO) travel) may be as small as 0.1 gram force to as large as 20 or more gram force. In some embodiments, a force target of 0.5 grams may be appropriate. In others, 1 gram, 2 grams, 4 grams, 8 grams or more may be appropriate. In some embodiments, a module height (longitudinal dimension) MH of 50 urns or less may be targeted while in others, a module height of 500 urns or more may be targeted. In some embodiments, overall module radial diameter or width MW may be 100 um or less or 400 urns or more (e.g., 150 um, 200 um, or 250 um). The spring beam element, or beam elements, of a module may have spring heights SH from 1 um or less to 100 um or more (e.g., 10, 20, 30, or 40 um) and beam widths or spring widths SW from 1 um or less to 100 um or more (e.g., 10, 20, 30, or 40 um). Tips may have uniform or changing geometries (e.g., with cylindrical, rectangular, conical, multi-prong, or other configurations, or combinations of configurations). Tips, where joining to spring beams, will generally possess larger cross-sectional widths TW than the widths SW of the beam or beams to which they connect.

[0067] FIG. 3 depicts an isometric view of a second example spring module 300 that is similar to the module of FIG. 2 with the exception that the two spring elements 321-1, 321-2 are thicker and, as such, provide a greater spring constant than that of the elements of FIG. 2. From another perspective, the example of FIG. 3 will require more force fora given deflection and, as such, will reach a yield strength (e.g., reach an elastic deflection limit) of the combined material and structural geometry with less deflection than the example of FIG. 2.

[0068] In other embodiments, spring modules may take different forms than those shown in FIG. 2 or FIG. 3. For example: (1) a module may have a single spring element or more than two spring elements; (2) each of the spring elements may have variations in one or more of widths, thicknesses, lengths, or extent of rotations; (3) spring elements may change over the lengths of the elements; (4) spring elements may have configurations other than Euler spirals, e.g. rectangular spirals, rectangular spirals with rounded comers, S-shaped structure, or C-shaped structures; (5) individual spring elements may connect to more than a single bridge junction, e.g. to bridge connection points located at 180 degrees around the module, 120 degrees or 90 degrees; (6) bridge junctions may be located on distinct bridges; (7) base elements may have smaller radial extents than spring/bridge junctions such that bases of higher modules may extend below upper extends of lower adjacent modules upon sufficient compression of module tips when modules are stacked; (8) module bases may be replaced with additional springs that allow compression of module springs from both directions upon deflection, (9) probe tips may not be laterally centered relative to the overall lateral configuration of the module (i.e. in the plane that is substantially perpendicular to the primary axis of compression or the primary build axis when formed on a layer-by-layer basis). PCT Application Attorney Docket No. 202718-201001/WO(MFT027CWO)

[0069] FIG. 4 depicts a partially cut view of a probe 400 including: (a) a plurality of spring modules 200-1, 200-2, 300-1, 300-2, some of which are of the FIG. 2 configuration 200-1 and 200-2 while others are of the FIG. 3 configuration 300-1 and 300-2, (b) a first tip 413, (c) a first or upper tip support or extension arm 414, (c) a first tip over-compression stop 412, (d) a second tip 423, (e) a second or lower tip support or extension arm 424, and (f) a sheath 401 (shown in a cut view that holds the spring modules in a substantially linear configuration with respect to one another as well as limiting the longitudinal extension of the tips) where the sheath has openings 410 and 420 for passing tip support arms 414 and 424, respectively. Tip 423 has a rectangular configuration that may be useful for contacting a solder bump or other protruding contact surface. In the probe design of FIG. 4, each module, if sufficient compression occurs, reaches a compression limit upon one of two events: (1) when the central portion of the lower spring element of a spring module comes into contact with the upper surface of the module base, or (2) when the lower surface of an immediately adjacent upper module base contacts the upper surface of the lower module bridge. The probe 400 as a whole may reach a compression limit when both an upper tip support arm 414 and a lower tip support arm 424 reach compression limits which may occur before any spring modules reach compression limits or after only a portion of the spring modules reach their own compression limits. Probes may have diameters of an appropriate size forthe array pitch desired. For example, effective probe diameters may be as small as 100 microns, or smaller, or as large as 600 microns, or larger. In some embodiments, for example, probes may have effective diameters in the range of 250 - 350 microns for use in an array having a 400 micron pitch or they may have effective diameters in the range of 150 to 250 microns for use in an array of 300 microns. Probe heights may be set to provide effective longitudinal travel so that overtravel requirements for individual modules, probes, or arrays as a whole can be accommodated when engaging semiconductor wafers or other electronic components. For example, overtravel may be in the range of 25 microns, or less, to 400 microns, or more, and probe heights may be in the range of 150 microns, or less, to 2000 microns, or more.

[0070] Numerous variations of the embodiments of the probe of FIG. 4 are possible and include for example: (1) module tips being joined to adjacent module bases or module tips may simply be contacted to adjacent module bases; (2) more than four or less than four spring modules may be used in forming a given probe; (3) some or all spring modules in a given probe may have similar spring constants and/or configurations or different spring constants and/or configurations; (4) tip arms may have compression stops located on them that are spaced from contact tips; (5) probes may have a contact tip on each end or may have a contact tip on one end and a bondable tip or attachment structure on the other end; (6) probes may have one or more PCT Application Attorney Docket No. 202718-201001/WO(MFT027CWO) fixed end caps that inhibit spring modules from sliding out of one or both ends of the sheath, or may have no fixed end caps; (7) probes may have sheath ends that allow spring module loading to occur and thus allow biasing of springs within the spring module without maintaining compressive pressure on probe end tips or that may allow modules to be formed in build locations that are different from working range locations within a sheath; (8) spring modules or tip arms may have sliding contacts or other contacts that allow current to be shunted away from the springs or spring elements and instead to flow through the sheaths; (9) modules may be formed with some dielectric elements; (10) spring modules and/or sheaths may include dielectric elements or be separated by dielectric elements such that electrical isolation of the spring modules/tip arms from the sheaths occurs, e.g. to provide dual electrically isolated conductive current paths or to ensure that central conductive paths of one probe of an array are not inadvertently shorted to a conductive path on another adjacent probe; (11) sheaths may be formed in two or more parts that allow formation or assembly of spring modules and other components into sheaths to form probes; (12) a plurality of spring modules may be formed in an attached manner to one another to provide a monolithic compliant structure (with or without tip arms and tips) that may be formed fully within a sheath, partially within a sheath for which loading will be completed subsequent to formation, or separate from a sheath for later assembly into a sheath;

(13) split sheaths may be formed with snap together features that provide for easy assembly after formation.

[0071] FIGS. 5A-5B, 6A-6B, 7A-7C, 8 to 10 provide side views of spring modules or compliant modules similar to those of FIGS. 2 and 3 with different compliant element rotational extents, with different rotational orientations between the pairs of compliant elements, with different base configurations for engaging array structures, and/or with different numbers of contact elements. In other embodiments, different configurations and combinations of features are possible.

[0072] The disclosed compliant or spring modules are combined to realize a probe being apt to make between two electronic circuit elements, in particular having at least one first tip to make contact to a first electronic circuit element, such as a contact pad or contact structure such a bump or pillar of a device under test DUT and at least a second tip to make contact to a second electronic circuit element, such as a contact pad or contact structure of an interposer or a PCB of a test circuitry (not shown in the figure). One of the tips may also be a structure that is to be bonded or attached to an electrical interface to the test circuitry.

[0073] FIGS. 5A and 5B show spring module 500 from a side view and a cut view respectively. As shown in FIG. 5B, spring elements 521-1, 521-2 of this spring module 500 have a polygonal shape and more specifically an octagonal shape. FIG. 5 A shows two spring PCT Application Attorney Docket No. 202718-201001/WO(MFT027CWO) elements 521-1 and 521-2, each having a right backside spring element portion 521 -IB and 521- 2B, respectively, and a left frontside spring element portion 521-1F and 521-2F, respectively. The right backside spring element portions 521-1B and 521-2B start at a standoff, orbridge, 511 and wrap around the back of a central moveable tip element 531 and then continue to become the left frontside element portions 521-1F and 521-2F which in turn join the tip element 531 on the front left of the probe 500. The spring elements 521-1, 521-2 of this spring module 500 are thus intertwined with each other. The standoff orbridge 511 bridges a longitudinal module gap between the spring elements 521-1 and 521-2 and a base 501. The springs or spring elements have an octagonal form with rotational extents between 180 degrees and 270 degrees. In alternative embodiments, the various elements of the module may take on different dimensional configurations and be formed from the same or different material, the various elements may be included in different multiple or singular quantities, and the spring may take different forms. For example: (1) the bridge may be formed from multiple separated bridge elements, (2) the spring elements may be provided in the form of three or more springs or as a single spring or be formed of multiple springs that are joined to one another at intermediate locations, (3) the spring elements may alternatively or additionally have different rotational extents, and be formed to have different curved, polygonal, straight, angular, or spiral configurations, (4) the base may have a configuration for accepting and laterally retaining (e.g. by surrounding or extending into) a tip of a lower spring module, or have an opening for allowing protrusion of a tip therethrough where the tip could be part of a preceding spring module or be part of the present spring module that extends from the bottom of the spring element or elements, and/or (5) tips may take on different configurations.

[0074] FIGS. 6A and 6B show spring module 600 from a side view and a cut view respectively. As shown in FIG. 6B, spring elements 621-1, 621-2 of this spring module 600 have a polygonal shape and more specifically an inward extending rectangular spiral shape. FIG. 6A shows the two spring elements 621-1 and 621-2 starting at a standoff, orbridge, 611 and wrapping around the back of a central contact element, or tip element, 631 as portions 621-1B and 621-2B and then extending around the front of the contact element, or tip element, 631 as portions 621-1F and 621-2F with thejoining location of the spring elements 621-1, 621-2 and the tip element 631 hidden from view such that the rotational extents of the spiral are something greater than 360 degrees. The spring elements 621-1, 621-2 of this spring module 600 are thus intertwined with each other. The standoff orbridge 611 bridges a longitudinal module gap between the spring elements 621-1 and 621-2 and a base 601. The full bridge to tip spiral of the top spring element can be seen in FIG. 6B along with portions of the material of the bridge 611 surrounding the initial portion of the spring element 621-2. Variations of the module of FIGS. PCT Application Attorney Docket No. 202718-201001/WO(MFT027CWO)

6A and 6B are possible and include, mutatis mutandis, the features and variations noted in the previous and subsequent module embodiments.

[0075] FIGS. 7A, 7B, and 7C show spring module 700 from a side view and at two different cut levels. FIG. 7 A shows the two spring elements 721-1 and 721-2 wrapping around a tip element 731 in different directions with an upper compliant element or spring element 721-2 having a rotational extent between 180 degrees and 360 degrees and with a lower compliant element or spring element 721-1 having its rotational extent hidden from view such that the extent is greater than 180 degrees. The upper spring element 721-2 has a right backside spring element portion 721-2B and a left frontside spring element portion 721-2F. A standoff orbridge 711 bridges a longitudinal module gap between the spring elements 721-1 and 721-2 and a base 701. When viewing from the top, the upper compliant element 721-2 has an inward spiral rotation in the counterclockwise direction while the lower compliant element or spring element 721-1 has a reversed rotation as shown in FIGS. 7A and 7B, respectively. The spring elements 721-1, 721-2 of this spring module 700 are thus intertwined with each other. The other reference numbers set forth in FIG. 7A - 7C show similar features to those shown by similar numbers in FIGS. 5A - 6B. Variations of the spring module of FIGS. 7A - 7C are possible and include, mutatis mutandis, the features and variations noted in the previous and subsequent spring module embodiments.

[0076] FIG. 8 shows a compliant or spring module 800 similar to that of FIG. 6 with the exception of a modification to the base of the compliant or spring module that is configured to allow the module to sit on and engage a recess or opening in or through an array structure (e.g. an array plate - not shown) wherein the compliant or spring module could be loaded in such recess or opening from the top of the array structure such that a central/lower portion 801-L of a base 801 thereof may slide into the recess to provide centering of the spring module within a slightly larger opening in the array plate while the outer edges of an upper portion 801-U of the base 801 provide a lip that can sit on the array plate surface to provide vertical or longitudinal positioning. In particular, the upper portion 801-U of the base 801 has at least one transversal size that is greater than a corresponding transversal size of the lower portion 800-L of the base 801, so that the outer edges of the upper portion 801-U of the base 801 can act as stopping elements for the spring module 800, while the lower portion 800-L slide into the recess of the array structure. The other reference numbers in FIG. 8 reference similar features as did the corresponding numbers in FIG. 6 with the exception that the numbers are incremented from the 600 series to the 800 series. Numerous variations of this embodiment are possible and include for example: (1) the compliant or spring module being configured to engage other position or retention structures such as probe sheaths, (2) the module base and the array opening have keyed features so that loading of the PCT Application Attorney Docket No. 202718-201001/WO(MFT027CWO) compliant or spring module into an opening in an engagement structure can only be completed when the rotational orientation (e.g. about the longitudinal axis of the module) is aligned with a complementary feature associated with the recess or opening in the engagement structure, (3) the base or the array structure may be provided with tabs, spring arms, springs arms with retention hooks or other locking features, or the like that provide for one or both of the enhanced lateral alignment or centering during engagement or improved retention of the compliant or spring module and an engagement structure.

[0077] FIG. 9 shows a compliant or spring module 900 similar to that of FIG. 8 with the exception of the module having a base 901 configured to abut and engage an array structure from below the array structure such that the compliant or spring module can be inserted into an opening in the array structure from below (while the compliant or spring module is in a tip-up orientation). An upper portion 901-U of the base 901 may slide into the opening to provide centering of the module within a slightly larger opening in the array plate while the outer edges of the lower portion 901-L of the base 901 provide a lip that can sit on the lower surface of the array plate to provide vertical or longitudinal positioning. In particular, the upper portion 901-U of the base 901 has at least one transversal size that is smaller than a corresponding transversal size of the lower portion 900-L of the base 901, so that the outer edges of the lower portion 901- L of the base 901 can act as stopping elements for the spring module 900, while the upper portion 900-U slide into the recess of the array structure. Variations of the embodiment of the compliant or spring module of FIG. 9 are possible and include those noted for the embodiment of FIG. 8. The other reference numbers in FIG. 9 refer to similar features as did the corresponding numbers in FIGS. 6 and 8 with the exception that the numbers are incremented from the 600 and 800 series, respectively, to the 900 series.

[0078] FIG. 10 shows a compliant or spring module similar to that of FIG. 5 with the exception that the spring module includes a lower contact element or tip 1031-B extending from a central portion of a base 1001 of the spring module 1000 such that the spring module 1000 is provided with two contact tips, namely a first or upper contact element or tip 1031 and the second or lower contact element or tip 1031-B. The other reference numbers in FIG. 10 refer to similar features as did the corresponding numbers in FIG. 5 with the exception that the numbers are incremented from the 500 series to the 1000 series. As disclosed with reference to FIG. 5, the spring module 1000 comprises two compliant or spring elements 1021-1 and 1021-2, each having a right backside spring element portion 1021-1B and 1021-2B, respectively, and a left frontside spring element portion 1021 -IF and 1021-2F, respectively. The right backside spring element portions 1021-1B and 1021-2B start at a standoff, orbridge, 1011 and wrap around the back of the upper tip 1031 and then continue to become the left frontside element portions 1021-1F and PCT Application Attorney Docket No. 202718-201001/WO(MFT027CWO)

1021-2F which in turn join the upper tip 1031 on the front left of the spring module 1000, the two compliant or spring elements 1021-1 and 1021-2 being thus intertwined with each other. The standoff orbridge 1011 bridges a longitudinal module gap between the spring elements 1021-1 and 1021-2 and the base 1001.

[0079] FIGS. 11 - 13 provide pairs of compliant or spring modules that share a common base with one of the modules oriented upward and the other oriented downward such that two oppositely oriented contact tips are provided along with two independently operable pairs of compliant elements wherein the example spring modules are similar to that of FIG. 6 and wherein different base structures are provided that allow for insertion to openings in an array structure from one or both directions and with or without guide features or features that provide for known lateral or longitudinal positioning.

[0080] FIG. 11 provides for a probe 1100 formed from a pair of joined and oppositely oriented compliant or spring modules having a common base or substrate 1101, separate upper and lower standoffs 1111-U and 1111-L supporting separate upper and lower pairs of planar springs 1121-2U and 1121-1U, and 1121-1L and 1121-2L, respectively, which in turn are connected to associated tips 1131-U and 1131-L. Such probes may be inserted into openings in an array structure where the base may sit on a surface of the array structure, the base may float within an opening in the array structure, or the base may enter an opening in the array structure and rest on a lip within the opening of the array structure. In such uses, insert may occur from above or below the array structure. In other uses, insertion may sandwich the bases of the probes between upper and lower array structures plates. In still other embodiments, the compliant or spring modules may be formed with or assembled with dielectric or conductive shield or skeleton structures which could form part of the probes. In still further embodiments, bonding materials such as solder may be added to selected locations on the modules or on any shield or skeleton structures to aid in mounting the module or probe to an array structure.

[0081] FIG. 12 provides a similar module or probe 1200 configuration to that shown in FIG. 11 with the exception that a base 1201 has a bottom 1201-L having a smaller diameter that a top 1201-U of the base 1201. Other reference numbers in FIG. 12 remain the same as noted for FIG. 11 with the exception that their series numbers have been incremented from 1100 to 1200. In particular, the probe 1200 is formed from a pair of joined and oppositely oriented compliant or spring modules having the common base 1201, separate upper and lower standoffs 1211-U and 1211-L supporting separate upper and lower pairs of planar springs 1221-2U and 1221-1U, and 1221-1L and 1221-2L, respectively, which in turn are connected to associated tips 1231-U and 1231-L. Furthermore, the reference numbers, as is also true for the other FIGS, set forth herein, also represent similar module or probe features as dotheir counterpart reference numbers in the PCT Application Attorney Docket No. 202718-201001/WO(MFT027CWO) other figures set forth herein. All the loading possibilities noted for the FIG. 11 example apply, but preferentially the probe 1200 may be loaded into an array structure from above, with the probe 1200 being in an up-facing configuration as shown in FIG. 12, particularly when the array structure has an opening larger than the bottom 1201-L of the base 1201 but smaller than the top 1201-U of the base 1201 such that the bottom 1201-L of the base 1201 and the walls of the opening in the array structure provide for some degree of lateral alignment when inserted (i.e. alignment perpendicular to the longitudinal axis of the probe 1200 or perpendicular to the primary compressional axis of the probe 1200) while the top 1201-U of the base 1201 provides for longitudinal alignment (i.e. known stopping location, or alignment, along the length of the probe 1200 from tip-to-tip). In the present embodiment, as in the other illustrated embodiments, it is assumed the base 1201 has a circular configuration so that any rotational alignment upon insertion is possible, but in other embodiments (particularly if the tips of the spring modules or probe are not centered), other configurations may be provided for the base 1201 and for the opening in the array structure such that rotational orientation of the probe 1200 and the array structure are ensured (e.g. (1) a square configuration could limit full insertion to four possible orientations, (2) an equilateral triangular configuration may limit full insertion to three orientations, (3) a rectangular or oval configuration may limit full insertion to two orientations, or (4) a non-equilateral triangular configuration may limit full insertion to a single orientation. Tabbed, notched or other configurations may also be used to limit full insertion to a single orientation.

[0082] FIG. 13 is like FIG. 12 with the exception that the base 1301 is provided with three distinct longitudinal levels as opposed to two such levels as in FIG. 12. A smaller diameter base configuration is provided at the upper 1301-U and lower 1301 -L portions of the base with a central or middle portion 1301-M having a larger diameter such that insertion of modules or probes can occur from above or below an array structure while still providing full engagement while avoiding the disadvantage that could occur if right-side-up or upside-down probe loading inadvertently occurred. Other reference numbers in FIG. 13 remain the same as noted for FIG. 12 with the exception that their series numbers have been incremented from 1200 to 1300. In particular, the probe 1300 is formed from a pair of joined and oppositely oriented compliant or spring modules having the common base 1301, separate upper and lower standoffs 1311-U and 1311-L supporting separate upper and lower pairs of planar springs 1321-2U and 1321-1U, and 1321-1L and 1321-2L, respectively, which in turn are connected to associated tips 13231-U and 1331-L. In other embodiments, precautions or configurational changes may limit the ability for inverted loading of modules.

[0083] FIG. 14 provides a side view of a partially formed array 1400 with three probe PCT Application Attorney Docket No. 202718-201001/WO(MFT027CWO) modules or probes 600, corresponding to the embodiment shown in FIG. 6, only as an example, at different stages of mounting to an array plate 1440 where the array plate 1440 may be a dielectric, a conductor, a dielectric with conductive traces or conductive vias, a conductive plate with dielectric regions that provide electrical isolation or selected connection to individual or groups of probes. The probes 600 may be mounted to the array plate 1440 using an adhesive, solder, solder with regions of solder masking material, ultrasonic bonding, laser welding, brazing, or the like. The probes 600 may be loaded onto the array plate 1440 one at a time or in groups. The probe modules or probes may be formed with desired array spacings and temporarily or permanently held together by conductive tethers or dielectric tethers.

[0084] FIG. 15 is similar to that of FIG. 14 with the exception that the array 1500 includes an array structurel540 that is provided with recesses 1541 for receiving probe modules or probes 600. Such recesses 1541 may be useful in helping to ensure proper probe positioning and possibly rotational alignment if necessary. The recesses 1541 may be formed with vertical side walls, with sloped side walls, or a combination of the two to aid in insertion. In some embodiments, the bases 601 of the probe module or probes 600 may alternatively or additionally have sloped sidewalls to aid in insertion and alignment.

[0085] FIG. 16 provides a side view of an array 1600 being formed with the loading of probes 800 of FIG. 8, as an example, into an array structure 1640 having through holes 1641 where three probes 800 are shown at different stages of loading with the bottom portion 801-L of the base 801 providing lateral alignment and the upper portion 801-U of the base 801 providing a lower lip which rests against an upper surface 1640A of the array structure 1640.

[0086] FIG. 17 provides a side view of an array 1700 being formed with the loading of probes 900 of FIG. 9 into an array structure 1740 having through holes 1741 into which three probes 900 are shown at different stages of loading with the upper portion 901-U of the base 901 providing lateral alignment and the lower portion 901-L of the base 901 providing an upper lip which rests against a lower surface 1740B of the array structure 1740.

[0087] FIG. 18A provides a view of the upper surface of an example three-by-three array structure 1840 with circular through holes 1841(1,1) to 1841(3,3).

[0088] FIG. 18B provides a cut view of the array structure 1840 of FIG. 18A along line 18B/18C - 18B/18C along with three probes 1200 (i.e., probes similar to those of FIG. 12 as an example) being loaded into the three openings at different stages of loading.

[0089] FIG. 18C shows a similar view of the array 1800 to that of FIG. 18B with the exception that the three probes 1200 have been loaded into their respective openings 1841 of an array structure 1840 and with the lower portion 1201-L of the probe bases 1201 providing lateral alignment and the upper portion 1201-U of the bases 1201 providing a lip which engages an PCT Application Attorney Docket No. 202718-201001/WO(MFT027CWO) upper surface 1840A of the array structure 1840 to provide longitudinal alignment.

[0090] Modules and probes may be formed using only multi-layer multi-material electrochemical methods as disclosed herein, partially using multi-layer multi-material electrochemical methods as disclosed herein or using some other method that does not involve electrochemical fabrication methods. When formed using electrochemical methods, probes may be built up by deposition of material such that upon completion of deposition and separation of any sacrificial material, a resulting configuration occurs: (1) a fully assembled probe array is formed, (2) a partially assembled probe array is formed with all or a portion of the array elements formed as part of the same build up process or as part of a build substrate, e.g. with all elements positioned and aligned for final movement from build locations to working locations, or (3) individual components formed separately or together but unaligned which can thereafter undergo be automated or manual assembly into operational probes.

[0091] FIG. 18D provides three example layer configurations (Examples A, B, and C) that may be used in forming the probe of FIG. 12. In Example A, the probe 1200A is formed from 12 layers LI -LI 2 with each formed with one or more structural materials, with the layers having different thickness, and with the layer levels dictated by longitudinal (z-direction) geometric changes that require different patterning for the successful formation of the probe structure. In Example B, the probe 1200B is formed with 17 layers L1-L17 with different build levels formed with multiple layers so that the layer thicknesses become more uniform. In Example C, the probe 1200C is formed with 26 layers L1-L26 with each layer having the same thickness. In other embodiments, different layer numbers and configurations may be used.

[0092] FIG. 19 provides a side view of a spring module 1900 similar to those of some of the previous embodiments (with like reference numbers representing similar features with the exception of updates to series numbers), with two primary exceptions: (1) the spring module 1900 includes not only a first upward facing tip 1931-U attached to the compliant elements but also a downward facing tip 1931-L attached to a lower surface of the base 1901 of the spring module 1900; and (2) the spring module 1900 is formed with only a single planar spring element 1921 identified by front and back portions 1921-F and 1921-B. A standoff orbridge 1911 bridges a longitudinal module gap between the spring element 1921 and the base 1901.

[0093] FIG. 20 provides a side view of a module 2000 according to another embodiment of the present disclosure wherein the spring module 2000 does not include a base but instead has a lower set of compliant planar elements shown with front and back portions as 2021-1F-L & 2021-1B-L and 2021-2F-L & 2021-2B-L whereas the upper pair of planar elements is represented with 2021-lF-U & 2021-1B-U and 2021-2F-U & 2021-2B-U. The spring module 2000 also includes an upper tip 2031-U and a lower tip 2031-L connected to their respective pairs PCT Application Attorney Docket No. 202718-201001/WO(MFT027CWO) of planar compliant elements. The pairs of planer compliant element 2021-U, 2021-L are joined to a common standoff orbridge 2011. In particular, the spring module 2000 comprises a first or upper compliant element 2021-U including two longitudinally spaced compliant elements 2021- 1-U, 2021 -2 -U which are functionally joined to the first tip 2031-U and a second or lower compliant element 2021-L including two longitudinally spaced compliant elements 2021-1-L, 2021 -2 -L which are functionally joined to the second tip 2031-L.

[0094] In this way, the upper compliant elements 2021-1-U, 2021-2 -U move together upon longitudinal compression of the first tip 2031-U toward the second tip 2031-L, and the lower compliant elements 2021-1-L, 2021-2 -L move together upon longitudinal compression of the second tip 2031-L toward the first tip 2031-U.

[0095] In other alternative embodiments, other compliant element arrangements may be used to engage upper and lower tips 2031-U, 2031-L, tips may or may not be centered, and tips may have different configurations to those shown. For example, tips may have (1) points, (2) elongated structures, (3) open structures (e.g., for engaging bumps), (4) structures with curved upper or lower surfaces, and (5) the like.

[0096] FIGS. 21A - 21C provide, respectively, a sideview of a module 2100 according to another embodiment of present disclosure (FIG. 21 A), a cut view through a down-facing engagement structure 2131-L, e.g. a ring as shown (FIG. 2 IB) of the module, and a side view of two laterally aligned longitudinally stacked modules (FIG. 21C) that engage one another via an internal region of the ring on the lower surface of the upper spring module 2100-U and a tip on the upper portion of the lower spring module 2100-L such that even under deflection, the two spring modules will remain engaged with one another without excessive lateral slippage or misalignment occurring. As shown in FIG. 21 A, the spring module 2100 has a pair of planar elements, which is represented with 2121-1F & 2121-1B and 2121-2F & 2121-2B. The spring module 2100 also includes an upper tip 2131-U connected to the pair of planar elements. A bridge, or standoff, 2111 bridges a longitudinal module gap between the planar elements and a base 2101. In other embodiments, different fully enclosed retention structure configuration may be used. In still other embodiments, the fully enclosed retention structure may be formed on a module tip while a base may have a structure extending therefrom that engages such fully enclosed retention structure. In still other alternative embodiments, the base may include a recess into which a tip of an adjacent module can be engaged.

[0097] FIGS. 22A - 22C provide three similar views to those shown in FIGS. 21 A - 21C for another module 2200 embodiment of the present disclosure wherein the engagement structure on the base 2201 of the present embodiment takes the form of an arc 2231-L, instead of a full ring, the opening of the arc facing toward the standoff, orbridge, 2211 with the direction of the PCT Application Attorney Docket No. 202718-201001/WO(MFT027CWO) opening selected to block any anticipated excess lateral movement of a tip against the base in absence of a barrier to slippage. As shown in FIG. 22A, the spring module 2200 has a pair of planar elements, represented with 2221-lF & 2221-1B and 2221-2F & 2221-2B. The spring module 2200 also includes an upper tip 2231-U connected to the pair of planar elements. The standoff orbridge 2211 bridges a longitudinal module gap between the planar elements and a base 2201. In other embodiments, the configuration of the open retention structure may take on other configurations with the open direction selected based on an anticipated direction of potential slippage between engaged modules.

[0098] FIGS. 23 A - 23B provide a side view of a module 2300 with a lower tip 2331-L that includes an engagement or retention structure (FIG. 23 A) that may be used to engage bumps of an electronic device that is to be contacted or that may be used to engage a tip 2331-U of another module as shown in the laterally aligned and longitudinally stacked modules of FIG. 23B wherein an upper tip 2331-U of the lower spring module 2300-L engages and is retained by the retention structure of the lower tip 2331-L of the upper spring module 2300-U so as to minimize slippage and misalignment risks during module stacking. The other reference numbers in FIGS. 23 A - 23B, with the exception the 2300 series number, are similar to those with corresponding reference numbers as set forth in the other figures. As shown in FIG. 23 A, the spring module 2300 has a pair of planar elements, which are represented with 2321-1F & 2321-1B and 2321-2F & 2321-2B. A standoff orbridge 2311 bridges a longitudinal module gap between the planar elements and a base 2301. In other embodiments, different retention structural configurations may be used, some may be closed, some may be open, some may involve complementary features on both of the surfaces that are to be engaged, some may simply involve textured surfaces that provide enhanced friction and thus provide for reduced slippage as compared to smooth surfaces. In still other embodiments, retention configuration may be replaced by direct bonding of contact surfaces to one another.

[0099] FIG. 24 provides a side view of a spring module 2400 according to another embodiment of the present disclosure where the module 2400 does not include a rigid base but does include a pair of compliant intermediate elements 2421-1M and 2421-2M that join two oppositely oriented stand offs 2411-U and 2411-L and compliant pairs of proximal and distal tip supporting spring elements which are represented with 2421-lF & 2421-1B and 2421-2F & 2421-2B. In particular, the pair of compliant intermediate elements 2421-1M and 2421-2M act as a laterally extended structure 2421-M which is at an intermediate longitudinal position between the first and second compliant elements 2421-U, 2421-L and provides a stop structure that inhibits excessive longitudinal motion of at least one of the first and second compliant elements 2421-U, 2421-L upon compression. The other reference numbers used in the drawing, PCT Application Attorney Docket No. 202718-201001/WO(MFT027CWO) with the exception of the 2400 series number, are similar to the corresponding references used in the other figures and particular to those of FIG. 11.

[00100] FIGS. 25A - 25B provide a side view and a cut view of a spring module 2500 according to another embodiment of the present disclosure where a base structure 2501 supports two laterally opposed standoffs 2511-1 and 2511-2 which each in turn support spiral compliant spring elements, 2521-1 and 2521-2, labelled as 2521-1F and 2521-2F, starting on the left, and 2521-1B and 2521-2B, starting on the right, such that a movable central tip 2531 is supported on each side by a spring force such that any tilting bias upon compression of the tip structure is reduced. The spring elements, 2521-1 and 2521-2, are coplanar spring elements that are intertwined, each of the spring elements, 2521-1 and 2521-2, being attached to the central tip 2531 and to a separate standoff, 2511-1 and 2511-2, respectively. The spring module 2500 can be joined to another spring module by the base 2501, in line with one of the previously described embodiments, such as the probe 1100 shown in FIG. 11 for instance. Each spring module is functionally joined to a respective first and second tip, so that the spring elements, 2521-1 and 2521-2 move together upon longitudinal compression of the first tip toward the second tip. Suitably, different rotational orientations may be provided between the pairs of compliant or spring elements, 2521-1 and 2521-2, in particular a same rotational orientation or opposite rotational orientations, as explained also with reference to FIGS. 7B and 7C, for instance. In other embodiments, different numbers of support springs may be used with their connection points having an appropriate angular orientation (e.g., three elements separated by 120°). Different springs may have different thicknesses, different widths or may vary in width or thickness from one end to another.

[00101] FIG. 26 provides a side view of module 2600 with a single spring element 2621 with front and back portions 2621-F and 2621-B supporting a tip 2631-U where the tip includes a down-facing extension 2651 that can act as a movement stop in the event that an excessive compression force is applied between the tip 2631-U and a base 2601. A standoff orbridge 2611 bridges a longitudinal module gap between the spring element and the base 2601. An engagement structure can be also provided on the base 2601 (not shown in FIG. 26).

[00102] FIG. 27 provides a side view of module 2700 with a single spring element 2721 with front and back portions 2721-F and 2721-B supporting a tip 2731-U and where a protruding stop structure 2752 extends upward from a base 2701 such that the lower portion of the tip will be engaged by the stop structure, in the event that an excessive compression force is applied between the tip 2731-U and the base. A standoff orbridge 2711 bridges a longitudinal module gap between the spring element 2721 and the base 2701. An engagement structure can be also provided on the base 2701 (not shown in FIG. 27). In other embodiments, stop elements may PCT Application Attorney Docket No. 202718-201001/WO(MFT027CWO) exist on both the moving tip as well as the base. In other embodiments, other stop structures may be used. An example of such alternative structures may include a standoff of one module being configured to contact a base of another module.

[00103] Still other embodiments may be created by combining features of the various embodiments and their alternatives which have been set forth herein with other embodiments and their alternatives which have been set forth herein.

[00104] Further Comments and Conclusions

[00105] Various other embodiments of the present disclosure exist. Some of these embodiments may be based on a combination of the teachings herein with various known teachings. For example, some embodiments may not use any blanket deposition process. Some embodiments may use selective deposition processes or blanket deposition processes on some layers that are not electrodeposition processes. Some embodiments may use nickel or nickelcobalt as a structural material while other embodiments may use different materials. For example, preferred spring materials include nickel (Ni), copper (Cu) in combination with one or more other materials, beryllium copper (BeCu), nickel phosphorous (Ni-P), tungsten (W), aluminum copper (Al-Cu), steel, P7 alloy, palladium, palladium cobalt, molybdenum, manganese, brass, chrome, chromium copper (Cr-Cu), and combinations of these. Some embodiments may use copper as the structural material with or without a sacrificial material.

[00106] Structural or sacrificial dielectric materials may be incorporated into embodiments of the present disclosure in a variety of different ways. Such materials may form a third material or higher deposited material on selected layers or may form one of the first two materials deposited on some layers.

[00107] Some embodiments may employ diffusion bonding or the like to enhance adhesion between successive layers of material or to reduce stress.

[00108] Various other embodiments of the present disclosure exist. Some of these embodiments may be based on a combination of the teachings herein with various known teachings. Some embodiments may not use any blanket deposition process and/or they may not use a planarization process. Some embodiments may use selective deposition processes or blanket deposition processes on some layers that are not electrodeposition processes. Some embodiments, for example, may use nickel, nickel-phosphorous, nickel-cobalt, gold, copper, tin, silver, zinc, solder, rhodium, rhenium as structural materials while other embodiments may use different materials. Some embodiments, for example, may use copper, tin, zinc, solder or other materials as sacrificial materials. Some embodiments may use different structural materials on different layers or on different portions of single layers. Some embodiments may remove a sacrificial material while other embodiments may not. Some embodiments may use photoresist, PCT Application Attorney Docket No. 202718-201001/WO(MFT027CWO) polyimide, glass, ceramics, other polymers, and the like as dielectric structural materials.

[00109] It will be understood by those of skill in the art that additional operations may be used in variations of the above presented embodiments. These additional operations may, for example, perform cleaning functions (e.g., between the primary operations discussed above), and they may perform activation functions and monitoring functions.

[00110] It will also be understood that the probe elements of some aspects of the present disclosure may be formed with processes which are very different from the processes set forth herein, and it is not intended that structural aspects of the present disclosure need to be formed by only those processes taught herein or by processes made obvious by those taught herein.

[00111] Though various portions of this specification have been provided with headers, it is not intended that the headers be used to limit the application of teachings found in one portion of the specification from applying to other portions of the specification. For example, alternatives acknowledged in association with one embodiment are intended to apply to all embodiments to the extent that the features of the different embodiments make such application functional and do not otherwise contradict or remove all benefits of the adopted embodiment. Various other embodiments of the present disclosure exist. Some of these embodiments may be based on a combination of the teachings set forth herein with various known teachings.

[00112] It is intended that any aspects of the present disclosure set forth herein represent independent disclosure descriptions which Applicant contemplates as full and complete disclosure descriptions that Applicant believes may be set forth as independent claims without need of importing additional limitations or elements, from other embodiments or aspects set forth herein, for interpretation or clarification other than when explicitly set forth in such independent claims once written. It is also understood that any variations of the aspects set forth herein represent individual and separate features that may form separate independent claims, be individually added to independent claims, or added as dependent claims to further define a disclosure being claimed by those respective dependent claims should they be written.

[00113] In view of the teachings herein, many further embodiments, alternatives in design and uses of the embodiments of the instant disclosure will be apparent to those of skill in the art. As such, it is not intended that the present disclosure be limited to the particular illustrative embodiments, alternatives, and uses described above but instead that it be solely limited by the claims presented hereafter.