Semiconductor device with flexible connector array

Abstract

The present application relates to a semiconductor device having an array of flexible connectors. A semiconductor device having an array of flexible connectors configured to relieve thermomechanical stress and associated systems and methods are disclosed herein. In one embodiment, a semiconductor assembly includes a substrate coupled to an array of flexible connectors. Each flexible connector is convertible between a rest configuration and a load configuration. Each flexible connector may include a conductive wire electrically coupled to the substrate and a support material at least partially surrounding the conductive wire. The conductive wire may have a first shape when the flexible connector is in the rest configuration and a second different shape when the flexible connector is in the load configuration.

Description

Technical Field

[0001] The present technology relates generally to semiconductor devices, and more particularly to semiconductor devices having flexible connector arrays configured to relieve thermomechanical stress. Background Art

[0002] Packaged semiconductor die including memory chips, microprocessor chips, and imager chips typically include a semiconductor die mounted on a substrate and encased in a protective covering. The semiconductor die may include functional features, such as memory cells, processor circuits, and imager devices, and bonding pads electrically connected to the functional features. The bonding pads may be electrically connected to terminals external to the protective covering to allow the semiconductor die to be connected to higher-level circuitry.

[0003] In some semiconductor assemblies, a packaged semiconductor die may be electrically coupled to a printed circuit board (PCB) via solder bumps arranged in a ball grid array (BGA). However, cyclic heating and / or cooling of the semiconductor package may induce significant thermomechanical stresses between the semiconductor package and the PCB due to the mismatch in the coefficients of thermal expansion of these components. Typically, the stresses may cause the semiconductor package to crack at or near the solder joints, which may render the semiconductor package inoperable. Summary of the invention

[0004] One aspect of the present disclosure relates to a semiconductor assembly comprising: a substrate; and an array of flexible connectors coupled to the substrate, each flexible connector being transformable between a rest configuration and a load configuration, wherein each flexible connector includes: a conductive wire electrically coupled to the substrate, the conductive wire having a first shape when the flexible connector is in the rest configuration, and having a second shape when the flexible connector is in the load configuration, the second shape being different from the first shape; and a support material at least partially surrounding the conductive wire.

[0005] In another aspect of the present disclosure, a method of manufacturing a semiconductor assembly includes: electrically coupling a first end portion of a conductive wire to a printed circuit board; surrounding at least a portion of the conductive wire with a supporting material; and electrically coupling a second end portion of the conductive wire to a substrate, wherein a length of the conductive wire between the first and second end portions is greater than a distance between the printed circuit board and the substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Many aspects of the present invention may be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale. Instead, the emphasis is placed on clearly illustrating the principles of the present invention.

[0007] Figure 1Ais a side cross-sectional view of a semiconductor assembly.

[0008] Figure 1B yes Figure 1A Side cross-sectional view of a semiconductor assembly subjected to thermomechanical stress.

[0009] Figure 2A is a side cross-sectional view of a semiconductor assembly including an array of flexible connectors configured in accordance with embodiments of the present technology.

[0010] Figure 2B yes Figure 2A Side cross-sectional view of a semiconductor assembly subjected to thermomechanical stress.

[0011] Figure 3A yes Figure 2A A side cross-sectional view of the flexible connector of the assembly in a rest configuration.

[0012] Figure 3B yes Figure 3A Side cross-sectional view of the flexible connector in a stretched configuration.

[0013] Figure 3C yes Figure 3A Side cross-sectional view of the flexible connector in a compressed configuration.

[0014] Figures 4A-4D is a side cross-sectional view of a flexible connector configured in accordance with other embodiments of the present technology.

[0015] Figures 5A-5F Various stages are shown of a method for fabricating a semiconductor assembly including an array of flexible connectors configured in accordance with embodiments of the present technology.

[0016] Figure 6 is a schematic diagram of a system including a semiconductor device or package configured according to an embodiment of the present technology. DETAILED DESCRIPTION

[0017] The following describes specific details of several embodiments of semiconductor devices and associated systems and methods. Those skilled in the art will recognize that the appropriate stages of the methods described herein may be performed at the wafer level or at the die level. Therefore, depending on the context in which it is used, the term "substrate" may refer to a wafer-level substrate or a singulated die-level substrate. In addition, unless the context indicates otherwise, conventional semiconductor manufacturing techniques may be used to form the structures disclosed herein. For example, chemical vapor deposition, physical vapor deposition, atomic layer deposition, plating, electroless plating, spin coating, and / or other suitable techniques may be used to deposit materials. Similarly, for example, plasma etching, wet etching, chemical mechanical planarization, or other suitable techniques may be used to remove materials.

[0018] In several embodiments described below, a semiconductor assembly configured according to the present technology may include a substrate coupled to a PCB via an array of flexible connectors. Each flexible connector can be transformed between a rest configuration and at least one load configuration (e.g., a compression configuration and / or a tension configuration). In some embodiments, each flexible connector includes a conductive element (e.g., a conductive wire) electrically coupled to the substrate and a support material at least partially surrounding the conductive element. The conductive element may have a first shape when the flexible connector is in a rest configuration, and a second different shape when the flexible connector is in a load configuration. The support material may deform as the flexible connector moves between the rest configuration and the load configuration. Therefore, when the assembly is subjected to thermomechanical stress, the flexible connector can be compressed and / or stretched without cracking or breaking. The flexible connector array of the present technology is expected to improve the reliability and robustness of semiconductor devices, especially in applications involving temperature and / or power cycles or other harsh field use scenarios such as automotive applications.

[0019] Although certain embodiments of the present invention are described herein with respect to a flexible connector for coupling a package substrate to a PCB, the present technology can also be used to couple other components of a semiconductor device to each other, such as two semiconductor dies, a semiconductor die and a substrate (e.g., a package substrate), etc.

[0020] Numerous specific details are disclosed herein to provide a thorough and useful description of embodiments of the present invention. However, those skilled in the art will appreciate that the technology may have additional embodiments and that the technology may be used without the following references. Figure 2A-6 The present invention is practiced without the need for several details of the embodiments described herein. For example, some details of semiconductor devices and / or packages well known in the art have been omitted so as not to obscure the present invention. In general, it should be understood that various other devices and systems besides those specific embodiments disclosed herein may be within the scope of the present invention.

[0021] As used herein, the terms "vertical," "lateral," "upper," "lower," "above," and "below" may refer to the relative direction or position of features in a semiconductor device in view of the orientation shown in the figure. For example, "upper" or "uppermost" may refer to a feature that is positioned closer to the top of the page than another feature. However, these terms should be broadly construed to include semiconductor devices having other orientations, such as inverted or tilted orientations, where top / bottom, over / under, above / under, up / down, and left / right may be interchanged depending on the orientation.

[0022] Figure 1A1 is a side cross-sectional view of a semiconductor assembly 100 ("assembly 100"). Assembly 100 includes a semiconductor package 102 coupled to a PCB 104 via a connector array 120 (eg, solder BGA). Semiconductor package 102 includes a semiconductor die 108 mounted on a package substrate 110 and encapsulated by a mold material 112.

[0023] Figure 1B 1 is a side cross-sectional view of assembly 100 when subjected to thermomechanical stresses, for example, during manufacturing and / or use. Thermomechanical stresses may be induced, for example, by the assembly process, by thermal cycling and / or thermal shock during component / board level reliability testing, and / or by temperature and / or power cycling during end-customer use. In some embodiments, semiconductor package 102 or a component thereof (e.g., package substrate 110) has a coefficient of thermal expansion (CTE) that is different from that of PCB 104, and the CTE mismatch between these components may cause them to deform (e.g., twist, bend) relative to each other during cooling and / or heating of assembly 100. For example, if Figure 1B As shown in , semiconductor package 102 and PCB 104 may have a distorted non-planar shape after heating and / or cooling. The relative deformation of semiconductor package 102 and PCB 104 may generate thermomechanical loads on connector 120, resulting in fatigue and / or creep failure. For example, Figure 1B As shown in FIG, cracks may form and propagate within connector 120. Cracks may also form and propagate at the joint between connector 120 and semiconductor package 102 or PCB 104. Once the crack length reaches a critical value, the electrical coupling between package 102 and PCB 104 may be disrupted, rendering assembly 100 fully or partially inoperable. This process may be accelerated under conditions where assembly 100 is subjected to cyclic loading and / or extreme temperature fluctuations (e.g., in automotive applications).

[0024] Figure 2A-2B2 is a side cross-sectional view of a semiconductor assembly 200 including an array of flexible connectors 220 configured in accordance with an embodiment of the present technology. The assembly 200 includes a semiconductor package 202 coupled to a PCB 204 via an array of flexible connectors 220. The semiconductor package 202 includes a semiconductor die 208, which may include a semiconductor substrate (e.g., a silicon substrate, a gallium arsenide substrate, an organic laminate substrate, etc.) and different types of semiconductor components and / or functional features, such as memory circuits (e.g., dynamic random access memory (DRAM), static random access memory (SRAM), flash memory, or other types of memory circuits), controller circuits (e.g., DRAM controller circuits), logic circuits, processing circuits, circuit elements (e.g., wires, traces, interconnects, transistors, etc.), imaging components, and / or other semiconductor features. Although the illustrated embodiment shows a single semiconductor die 208, in other embodiments, the semiconductor package 202 may include multiple semiconductor dies (e.g., two, four, five, six, seven, eight, nine, ten, or more dies) arranged in a die stack.

[0025] The semiconductor die 208 may be carried by a packaging substrate 210, which may include a redistribution layer, an interposer, a printed circuit board, a dielectric spacer, another semiconductor die (e.g., a logic die), or another suitable substrate. In some embodiments, the packaging substrate 210 includes semiconductor components (e.g., a doped silicon wafer or a gallium arsenide wafer), non-conductive components (e.g., various ceramic substrates such as aluminum oxide (Al2O3), etc.), aluminum nitride, and / or conductive portions (e.g., interconnect circuitry, through silicon vias (TSVs), etc.). The packaging substrate 210 may be electrically coupled to the semiconductor die 208 via a plurality of interconnects (e.g., bumps, micro-bumps, pillars, studs, columns, etc.—not shown).

[0026] The semiconductor package 202 may further include a mold material 212 formed over the package substrate 210 and / or at least partially surrounding the semiconductor die 208. The mold material 212 may be a resin, an epoxy, a silicone-based material, a polyimide, or any other material suitable for encapsulating the semiconductor die 208 and / or at least a portion of the package substrate 210 to protect these components from contaminants and / or physical damage. In some embodiments, the semiconductor package 202 includes other components such as an external heat sink, a sleeve (e.g., a thermal sleeve), an electromagnetic interference (EMI) shielding component, and the like.

[0027] The semiconductor package 202 may be electrically coupled to the PCB 204 via an array of flexible connectors 220 (e.g., solder balls, conductive bumps, conductive pillars, conductive epoxy, and / or other suitable conductive elements). Each flexible connector 220 may electrically couple the package substrate 210 to the PCB 204, for example, via corresponding bonding pads (not shown) on the surfaces of these components. Thus, the semiconductor die 208 may be electrically coupled to the PCB 204 via the package substrate 210 and the flexible connectors 220. Optionally, the flexible connectors 220 may be surrounded by an underfill material (not shown).

[0028] The flexible connector 220 is configured to mitigate the effects of thermomechanical stress and reduce the probability of failure of the assembly 200. For example, the flexible connector 220 can be more compliant than conventional materials (e.g., solid metal structures such as solder balls) used to connect the semiconductor package 202 and the PCB 204. Thus, when the assembly 200 is subjected to thermomechanical loads (e.g., Figure 2B 204 ), the flexible connector 220 may deform (e.g., elastically and / or plastically) or otherwise change geometry to dissipate stresses that would otherwise cause cracking or other failure modes. In some embodiments, the flexible connector 220 is configured to deform elastically when the assembly 200 is subjected to thermal mechanical loads, with little or no plastic deformation. The flexible connectors 220 may each have a target length range based on the gap distance between the package 202 and the PCB 204, and in operation the flexible connector 220 may be compressed or extended by 5%, 10%, 15%, 20%, 25%, 30%, 34%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75% and / or any percentage from 5% to 75% relative to the target length range and remain fully operational. Optionally, the flexible connector 220 may be surrounded by an underfill material (not shown), which may provide further cushioning to dissipate applied stresses and / or increase the mechanical strength of the assembly 200.

[0029] In some embodiments, each flexible connector 220 of the array is configured to transform between a rest configuration and at least one loaded configuration without mechanical failure (e.g., cracking, rupture, creep, fatigue, etc.). The rest configuration can be one in which the flexible connector 220 and / or the assembly 200 is subjected to little or no thermomechanical load (e.g., such as Figure 2A For example, the flexible connector 220 may be in a rest configuration prior to operation of the assembly 200 (e.g., prior to thermal and / or power cycling). Load configurations may include where the flexible connector 220 and / or the assembly 200 is subjected to a thermomechanical load (e.g., such as Figure 2B200 ), such as a tension configuration and / or a compression configuration. For example, the flexible connector 220 can be in a loaded configuration during or after operation of the assembly 200 (e.g., during or after thermal and / or power cycling) and / or in an ambient environment having low (e.g., below -20°C) or high (e.g., above 40°C) temperatures. The ability of the flexible connector 220 to transform between different configurations without mechanical failure can increase the robustness and reliability of the assembly 200, such as even under cyclic loading and / or severe operating conditions.

[0030] Optionally, when the assembly 200 is subjected to thermomechanical loads, the flexible connectors 220 at different portions of the assembly 200 may be subjected to different loads and thus may be in different configurations. For example, some flexible connectors 220 may be in a loaded configuration (e.g., a tension or compression configuration), while other flexible connectors 220 may be in a rest configuration. As another example, the flexible connectors 220 at or near an edge of the assembly 200 may be in a tension configuration, while the flexible connectors 220 at or near an interior portion of the assembly 200 may be in a compression configuration.

[0031] Figures 3A-3C According to an embodiment of the present invention Figure 2A and 2B More specifically, Figure 3A The flexible connector 220 is shown in a rest configuration, Figure 3B The flexible connector 220 is shown in a stretched configuration (eg, under tension), and Figure 3C The flexible connector 220 is shown in a compressed configuration (eg, under compression).

[0032] First see Figure 3A , the flexible connector 220 includes a conductive element 300 configured to electrically couple the package substrate 210 and the PCB 204. The conductive element 300 can be an elongated structure such as a wire, a filament, a tape, a coil, etc. The conductive element 300 can be made of any suitable conductive material such as copper, nickel, gold, silicon, tungsten, conductive epoxy, or a combination thereof. For example, in some embodiments, the conductive element 300 is a conductive metal wire, such as a gold wire or a copper wire. The conductive element 300 can be flexible enough to change shape while maintaining electrical connectivity between the PCB 204 and the package substrate 210, as described in more detail below.

[0033] In some embodiments, conductive element 300 includes a first end portion 302a coupled to PCB 204 (eg, coupled to bonding pad 304), and a second end portion 302b coupled to package substrate 210 (eg, coupled to bonding pad 306). Figure 3AAs shown in FIG. 1 , when the flexible connector 220 is in the rest configuration, the length of the conductive element 300 between the first and second end portions 302a-b is greater than the spacing or gap distance d between the PCB 204 and the package substrate 210. 1 For example, the length of the conductive element may be comparable to the distance d 1 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or 100% greater. Thus, in the rest configuration, the conductive element 300 can have a curved shape (e.g., a bend, fold, spiral, helical, serpentine, zigzag, or other nonlinear shape). The curvature of the conductive element 300 can allow the conductive element 300 to change shape (e.g., expand and / or contract) in response to thermomechanical loads, as described in more detail below. For example, in the illustrated embodiment, the conductive element 300 has a serpentine shape having three vertices 301a-c between the first and second end portions 302a-b. As shown in FIG. Figure 3A , the vertices 301a-c can each have a rounded shape and can extend laterally outward relative to the central longitudinal axis of the flexible connector 220. Although the illustrated embodiment includes three vertices 301a-c, in other embodiments, the conductive element 300 can include fewer or more vertices (e.g., one, two, four, five, six, seven, eight, nine, ten, or more vertices). Additional geometric shapes suitable for the conductive element 300 are further described below.

[0034] The flexible connector 220 may further include a support material 308 that partially or completely surrounds the conductive element 300 to provide mechanical support thereto. In the illustrated embodiment, for example, the conductive element 300 is embedded and / or encapsulated in the support material 308. The support material 308 may be coupled to the bonding pads 304 and 306, and in some cases to the surface of the package substrate 210 and / or the PCB 204. In some embodiments, the support material 308 is a relatively soft and / or compliant material (e.g., a polymer or resin) that is configured to deform (e.g., elastic and / or plastic, by stretching and / or compressing) when a thermomechanical load is applied, as described in more detail below. The support material 308 may be a curable material (e.g., an epoxy resin) that can be cured from a liquid state to a solid or semi-solid state by applying energy (e.g., heat and / or light). Optionally, the support material 308 may be non-conductive in order to reduce or avoid electrical interference (e.g., electrical interference with adjacent flexible connectors 220).

[0035] The support material 308 can be configured in many different ways. For example, the support material 308 can have any suitable shape, such as a sphere, a bump, a spherical, an ellipsoidal, or a cylindrical shape. In some embodiments, the support material 308 has a uniform cross-sectional dimension (e.g., area, diameter, width, etc.). In other embodiments, different portions of the support material 308 can have different cross-sectional dimensions. The cross-sectional dimension of the support material 308 can be greater than the cross-sectional dimension of the conductive element 308. For example, the cross-sectional dimension (e.g., minimum, maximum, and / or average cross-sectional dimension) of the support material 308 can be at least 2, 5, 20, 25, 20, 25, 30, 40, or 50 times the cross-sectional dimension of the conductive element 308.

[0036] Next reference Figure 3B In some embodiments, when subjected to tensile thermomechanical loads, the PCB 204 and the package substrate 210 may twist, bend, or otherwise move away from each other to an increased separation or gap distance d 2 The increased spacing distance d 2 Comparable initial separation distance d 1 The flexible connector 220 is at least 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% or 100% larger. Thus, the flexible connector 220 is transformed into a stretched configuration (e.g., Figure 3B ). The shape of the conductive element 300 may also be changed to a linear, substantially linear, and / or less curved shape having a reduced amount of curvature as compared to the rest configuration. For example, in the illustrated embodiment, the conductive element 300 has a substantially linear shape in which the vertices 301a-c have been vertically moved away from each other and / or laterally moved inward toward the central longitudinal axis of the flexible connector 220. Similarly, the support material 308 may also be transformed into an elongated shape having a reduced cross-sectional dimension (e.g., area, diameter, width) as compared to the rest configuration. For example, the cross-sectional dimension (e.g., minimum, maximum, and / or average cross-sectional dimension) of the support material 308 in the stretched configuration may not exceed 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, or 90% of the cross-sectional dimension of the support material 308 in the rest configuration. The shape change of the conductive element 300 and / or the support material 308 may be primarily or entirely based on elastic deformation, with little or no plastic deformation.

[0037] Next reference Figure 3C In other embodiments, when subjected to compressive thermomechanical loads, the PCB 204 and the package substrate 210 may twist, bend, or otherwise move toward each other to a reduced separation or gap distance d 3 . Reduced separation distance d 3 The initial separation distance d may not exceed 110%, 20%, 30%, 40%, 50%, 60%, 70%, 80% or 90%. Therefore, the flexible connector 220 is transformed to a compressed configuration (e.g., Figure 3C ). The conductive element 300 may also be transformed into a more curved shape having a greater amount of curvature as compared to the rest configuration. For example, in the illustrated embodiment, the conductive element 300 has been transformed into a more curved serpentine shape, wherein the vertices 301a-c have been moved vertically toward each other and / or laterally outwardly away from the central longitudinal axis of the flexible connector 220. Similarly, the support material 308 may also be transformed into a shortened shape having an increased cross-sectional dimension (e.g., area, diameter, width) as compared to the rest configuration. For example, the cross-sectional dimension (e.g., minimum, maximum, and / or average cross-sectional dimension) of the support material 308 in the stretched configuration may be at least 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or 100% greater than the cross-sectional dimension of the support material 308 in the rest configuration. The shape change of the conductive element 300 and / or the support material 308 may be primarily or entirely based on elastic deformation, with little or no plastic deformation.

[0038] Figures 4A-4D is a side cross-sectional view of a flexible connector 220 for electrically coupling a package substrate 210 to a PCB 204 according to other embodiments of the present technology. Figures 4A-4D The features of the embodiments of the present invention may be combined with each other and / or with other embodiments described herein (e.g., Figures 3A-3C In addition, Figures 4A-4D Any of the embodiments of may be implemented as a semiconductor assembly (eg, Figure 2A-2B A portion of the assembly 200).

[0039] Figure 4A The flexible connector 220 is shown with a conductive element 400. The conductive element 400 may be substantially similar to the conductive element 400 of FIG. Figures 3A-3C The conductive element 300 is described above, except that the conductive element 400 has a single vertex 401 instead of multiple vertices. The vertex 401 can extend laterally outward from the central longitudinal axis of the flexible connector 220 so that the conductive element 400 is curved. The curvature of the vertex 401 can increase or decrease accordingly as the flexible connector 220 is compressed or stretched. Although the vertex 401 is Figure 4A As having a rounded shape, but in other embodiments, the apex 401 may have a pointed or sharp shape.

[0040] Figure 4BA flexible connector 220 is shown having a conductive element 402 having a spiral or helical shape. The conductive element 402 may include a plurality of coils 403 arranged vertically along a central longitudinal axis of the flexible connector 220. As the flexible connector 220 is compressed or stretched, the coils 403 may move vertically toward or away from each other, respectively. Alternatively or in combination, the coil size may increase or decrease, respectively, as the flexible connector 220 is compressed or stretched. Although Figure 4B The embodiment includes three coils 403, but in other embodiments, the conductive element 402 may include fewer or more coils (e.g., one, two, four, five, six, seven, eight, nine, ten or more coils).

[0041] Figure 4C A flexible connector 220 is shown having a conductive element 404 having a folded or zigzag shape. The conductive element 404 may be substantially similar to a Figures 3A-3C Conductive element 300 is depicted except that conductive element 404 is comprised of linear segments rather than curved segments and vertices 405a-c have a pointed shape rather than a rounded shape. Vertices 405a-c can move laterally outward and / or vertically together as flexible connector 220 compresses, and can move laterally inward and / or vertically apart as flexible connector 220 stretches. Figure 4C The embodiment includes three vertices 405a-c, but in other embodiments, the conductive element 404 may include fewer or more vertices (e.g., one, two, four, five, six, seven, eight, nine, ten, or more vertices).

[0042] Figure 4D A flexible connector 220 is shown having a conductive element 406 having a serpentine shape with a plurality of vertices 407a-b. The conductive element 406 may be substantially similar to a Figures 3A-3C Conductive element 300 is depicted with vertices 407a-b oriented in a vertical or substantially vertical direction rather than in a transverse direction. Vertices 407a-b may move vertically toward each other as flexible connector 220 stretches, and may move vertically away from each other as flexible connector 220 compresses. Figure 4D The embodiment of the present invention includes two vertices 407a-b, but in other embodiments, the conductive element 406 may include fewer or more vertices (e.g., one, three, four, five, six, seven, eight, nine, ten, or more vertices). In addition, in other embodiments, the vertices 407a-b may have a pointed shape rather than a rounded shape.

[0043] Figures 5A-5FVarious stages of a method for manufacturing a semiconductor assembly having an array of flexible connectors configured according to an embodiment of the present technology are shown. The method can be used to manufacture any embodiment of the semiconductor assembly and flexible connector described herein, such as Figure 2A-2B , 3A-3C and 4A-4D embodiments.

[0044] First see Figure 5A , a PCB 204 having a plurality of bonding pads 304 (eg, copper bonding pads) is provided. The bonding pads 304 may be formed in an array or other patterned arrangement, as known to those skilled in the art.

[0045] Next reference Figure 5B , forming a first end portion 302a of a conductive element (e.g., a conductive wire), and electrically coupled to a bonding pad 304 on the PCB 204, for example, using wire bonding or another suitable process. In some embodiments, the coupling is performed using a manufacturing apparatus having a nozzle 500, which is configured to form a wire-bonded conductive element on the bonding pad 304, as known to those skilled in the art. The nozzle 500 may include an internal lumen 502 through which a conductive material 503 may flow to form the conductive element.

[0046] Next reference Figure 5C As the conductive material 503 exits the lumen 502 and cools, a conductive element 300 having at least one bend (e.g., a kink, a spiral, a helix, a fold, etc.) is formed. In some embodiments, the bend is formed by moving the nozzle 500 along a predetermined trajectory as the conductive material 503 flows from the interior lumen 502. For example, the conductive element 300 may be formed along a shape having the same or similar shape as the desired shape of the conductive element 300 (e.g., a shape relative to the shape of the conductive element 300 described herein). Figures 3A-3C 4A-4D). Alternatively or in combination, the nozzle 500 may be moved vertically upward to a predetermined height to form a row of conductive material 503 in a straight line having a desired length, and then moved vertically downward to bend, fold, or otherwise present a curved shape to form the conductive element 300.

[0047] Next reference Figure 5D, the conductive element 300 is at least partially surrounded by the support material 308. The support material 308 can be delivered from the nozzle 500, for example, from the outer lumen 504 surrounding the inner lumen 502. In other embodiments, the support material 308 can be delivered from a separate device. Optionally, the support material 308 can be delivered in a liquid and / or uncured form, and its viscosity is configured so that the support material 308 can be ejected from the nozzle 500 to surround the conductive element 300 without flowing or encroaching on other parts of the PCB 204. The support material 308 can be solidified and / or cured (e.g., using heat, light) simultaneously with or after the delivery of the support material 308 from the nozzle 500. In other embodiments, the support material 308 is solidified and / or cured at a later stage of the manufacturing process, as described below.

[0048] Next reference Figure 5E , the nozzle 500 is separated from the conductive element 300, thereby exposing the second end portion 302b of the conductive element 300. Figures 5B-5D The process described is to form an array of flexible connectors 220. In some embodiments, a single nozzle is used to sequentially form each flexible connector 220. Alternatively, an array of nozzles can be used to form multiple flexible connectors 220 simultaneously.

[0049] Next reference Fig. 5F , the second end portion 302b of each conductive element 300 is electrically coupled to the package substrate 210 (e.g., via the bonding pad 306). The package substrate 210 may be part of a semiconductor package (not shown) such that the conductive elements 300 electrically couple the PCB 204 to the semiconductor package, as previously described. In some embodiments, the package substrate 210 includes a plurality of bonding pads 306 formed in an array or other patterned arrangement, and the bonding pads 306 are aligned and contacted with the flexible connector 220 and / or the second end portion 302b. The bonding pads 306 may then be bonded or otherwise coupled to the flexible connector 220 and / or the second end portion 302b according to methods known to those skilled in the art. For example, in embodiments in which the support material 308 is in liquid and / or uncured form, the support material 308 may also solidify and / or cure to mechanically couple the package substrate 210 to the flexible connector 220 and / or the PCB 204.

[0050] Relative to Figures 5A-5FThe described method can be implemented in a number of different ways. For example, the support material 308 can be delivered to the PCB 204 before the conductive element 300. In such embodiments, the conductive element 300 can then be pushed through the support material 308 to contact and couple to the PCB 204. As another example, the array of flexible connectors 220 can be formed on the packaging substrate 210 instead of the PCB 204. In yet another example, the array of flexible connectors can be formed on a separate manufacturing substrate, then separated from the manufacturing substrate and coupled between the packaging substrate 210 and the PCB 204.

[0051] With above reference Figure 2A-5F Any of the semiconductor devices and / or packages of the described features may be incorporated into any of a number of larger and / or more complex systems, a representative example of which is Figure 6 The system 600 is schematically shown in FIG. The system 600 may include a processor 602, a memory 604 (eg, SRAM, DRAM, flash, and / or other memory devices), an input / output device 606, and / or other subsystems or components 608. Figure 2A-5F The described semiconductor die and / or package may be included in Figure 6 . The resulting system 600 may be configured to perform any of a wide variety of suitable computing, processing, storage, sensing, imaging, and / or other functions. Accordingly, representative examples of system 600 include, but are not limited to, computers and / or other data processors, such as desktop computers, laptop computers, network appliances, handheld devices (e.g., palmtop computers, wearable computers, cellular or mobile phones, personal digital assistants, music players, etc.), tablet computers, multiprocessor systems, processor-based or programmable consumer electronic devices, network computers, and microcomputers. Additional representative examples of system 600 include lights, cameras, vehicles, etc. With respect to these and other examples, system 600 may be housed in a single unit or distributed over multiple interconnected units, for example, via a communication network. Therefore, components of system 600 may include any of local and / or remote memory storage devices and various suitable computer-readable media.

[0052] It should be understood from the above that although specific embodiments of the present technology have been described herein for illustrative purposes, various modifications may be made without departing from the present disclosure. Therefore, the present invention is not limited except by the appended claims. In addition, certain aspects of the new technology described in the context of specific embodiments may also be combined or removed in other embodiments. In addition, although the advantages associated with certain embodiments of the new technology have been described in the context of those embodiments, other embodiments may also exhibit these advantages, and not all embodiments must exhibit these advantages to fall within the scope of the present technology. Therefore, the present disclosure and associated technologies may cover other embodiments that are not explicitly shown or described herein.

Claims

1. A semiconductor assembly comprising: substrate; as well as an array of flexible connectors coupled to the substrate, each flexible connector being convertible between a rest configuration and a load configuration, wherein each flexible connector comprises— a conductive line electrically coupled to the substrate, the conductive line having a first shape when the flexible connector is in the rest configuration and a second shape when the flexible connector is in the load configuration, the second shape being different from the first shape, wherein the first shape is a first serpentine shape, the first serpentine shape comprising a plurality of vertices, the plurality of vertices being laterally spaced apart from a central longitudinal axis of the flexible connector by a plurality of first distances, and wherein the second shape is a second serpentine shape, the second serpentine shape comprising the plurality of vertices, the plurality of vertices being laterally spaced apart from the central longitudinal axis by a plurality of second distances, the plurality of second distances being different from the first plurality of distances, and A support material at least partially surrounds the conductive wire.

2. The semiconductor assembly according to claim 1, wherein: The loading configuration is a compressive configuration and the second shape has a greater amount of curvature than the first shape, or the loading configuration is a tensile configuration and the second shape has a lesser amount of curvature than the first shape.

3. The semiconductor assembly according to claim 1, wherein: Each flexible connector is convertible between the rest configuration and a second load configuration, and The conductive line has a third shape when the flexible connector is in the second load configuration, the third shape being different from the first and second shapes. 4 . The semiconductor assembly of claim 1 , wherein the support material is configured to elastically deform as the flexible connector transforms between the rest configuration and the load configuration. The semiconductor assembly of claim 1 , wherein the support material comprises a polymer.

6. The semiconductor assembly of claim 1 , wherein each flexible connector has a target length range based on a gap distance between the substrate and a printed circuit board coupled to the substrate via the array of flexible connectors, and wherein in operation each flexible connector can be compressed or extended 5%-75% from the target length range and remain fully operational. The semiconductor assembly of claim 1 , wherein the support material is spherical or elliptical in shape.

8. The semiconductor assembly of claim 1 , wherein the support material has a maximum load cross-sectional area when the flexible connector is in the load configuration, and the support material has a maximum rest cross-sectional area when the flexible connector is in the rest configuration, and Wherein the maximum load cross-sectional area differs from the maximum rest cross-sectional area by at least 10% of the value of the maximum rest cross-sectional area.

9. The semiconductor assembly of claim 1, wherein a maximum cross-sectional width of the support material is at least 25 times greater than a cross-sectional width of the conductive line.

10. The semiconductor assembly of claim 1, wherein at least one end portion of the conductive line has a cross-sectional area greater than a middle portion of the conductive line.

11. The semiconductor assembly of claim 1, wherein the first shape and the second shape include three or more vertices.

12. The semiconductor assembly of claim 1, wherein the plurality of vertices are located in a same vertical plane.

13. A method of manufacturing a semiconductor assembly, the method comprising: electrically coupling the first end portion of the conductive wire to the printed circuit board; surrounding at least a portion of the conductive wire with a support material to form a flexible connector; as well as electrically coupling the second end portion of the conductive line to the substrate, wherein a length of the conductive line between the first and second end portions is greater than a distance between the printed circuit board and the substrate, wherein the conductive line has a first serpentine shape when the flexible connector is in a rest configuration and has a second serpentine shape when the flexible connector is in a loaded configuration, wherein the first serpentine shape has a plurality of vertices, the plurality of vertices being laterally spaced apart from a central longitudinal axis of the flexible connector by a plurality of first distances, and The second serpentine shape includes the plurality of vertices, the plurality of vertices being laterally spaced apart from the central longitudinal axis by a plurality of second distances, respectively, the plurality of second distances being different from the first plurality of distances. The method of claim 13 , wherein the first end portion is electrically coupled to the printed circuit board by wire bonding.

15. The method of claim 13, further comprising forming at least one bend, bend, spiral, helix, or fold in the conductive line between the first and second end portions.

16. The method of claim 13, wherein the support material comprises a curable material, and wherein the method further comprises curing the curable material.

17. The method of claim 16, wherein the curable material is cured using heat or light.

18. The method of claim 16, wherein the curable material is cured after surrounding at least the portion of the conductive line with the curable material.

19. The method of claim 13, further comprising delivering the conductive wire and the support material from a nozzle of a fabrication apparatus.

20. The method of claim 19, further comprising moving the nozzle along a predetermined trajectory as the conductive line is delivered from the nozzle so as to form at least one bend, bend, spiral, helix, or fold in the conductive line.

21. The method of claim 19, wherein the conductive wire is delivered from an interior lumen of the nozzle and the support material is delivered from an exterior lumen of the nozzle.

22. The method of claim 19, wherein the conductive wire is delivered from the nozzle prior to delivering the support material from the nozzle.

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