Wafer alignment structure

Abstract

A system-on-wafer (SoW) assembly is disclosed. The SoW assembly can include a first SoW assembly structure with a first coefficient of thermal expansion (CTE). The first SoW assembly structure includes first through third slots at different locations. The SoW assembly can include a second SoW assembly structure stacked on the first SoW assembly structure. The second SoW assembly structure has a second CTE different from the first CTE. The second SoW assembly structure has first through third pins extending from the second SoW assembly structure and disposed in the first through third slots. The first and second slots are shaped to allow the first and second pins to move along a first axis, and the third slot is shaped to allow the third pin to move along a second axis. In certain applications, the first SoW assembly structure can be a SoW and the second SoW assembly structure can be a heat dissipating structure.

Description

Technical Field

[0001] (Cross - Reference to Related Applications) This application claims the benefit of U.S. Provisional Patent Application No. 63 / 155,202, filed on March 1, 2021, entitled "WAFER ALIGNMENT STRUCTURE", the disclosure of which is incorporated herein by reference in its entirety for all purposes.

[0002] The present disclosure generally relates to alignment structures, and more specifically, to wafer - level alignment structures.

Background Art

[0003] Accurately aligning elements with respect to other elements at the wafer level can be difficult. In systems such as system - on - wafer assemblies, elements with high coefficient of thermal expansion (CTE) and low CTE elements can be attached to each other. For example, a system - on - wafer and a heat - dissipation structure can have different CTEs and can be attached to each other. The mismatch between the CTEs of the elements causes misalignment between the elements due to thermal stress.

Summary of the Invention

[0004] In one embodiment, a system-on-wafer (SoW) assembly is disclosed. The SoW assembly may include a first SoW assembly structure comprising a first slot in a first position, a second slot in a second position, and a third slot in a third position. The SoW assembly may include a second SoW assembly structure stacked with the first SoW assembly structure. The second SoW assembly structure has a first pin extending from the second SoW assembly structure and at least partially located in the first slot, a second pin extending from the second SoW assembly structure and at least partially located in the second slot, and a third pin extending from the second SoW assembly structure and at least partially located in the third slot. The first and second slots are molded to allow the first and second pins to move along a first axis in one plane, and the third slot is molded to allow the third pin to move along a second axis different from the first axis in the plane. Either the first SoW assembly structure or the second SoW assembly structure is included in a thermal system configured to cool the SoW.

[0005] In one embodiment, elements can be stacked with a SoW.

[0006] In one embodiment, the element includes a SoW. The SoW assembly may further include a reinforcing component coupled to the SoW. The reinforcing component may include an opening that aligns with a first slot. The size of the opening may be smaller than the size of the first slot so that the reinforcing component prevents the first pin from physically contacting the SoW. The opening may have an elliptical shape. The first axis may be substantially perpendicular to the second axis.

[0007] In one embodiment, a system-on-wafer (SoW) assembly is disclosed. The SoW assembly may include a first SoW assembly structure having a first coefficient of thermal expansion, the first SoW assembly structure including a first slot in a first position, a second slot in a second position, and a third slot in a third position. The SoW assembly may include a second SoW assembly structure stacked on the first SoW assembly structure and configured to dissipate heat from the SoW. The second SoW assembly structure has a second coefficient of thermal expansion different from the first coefficient of thermal expansion. The second SoW assembly structure includes a first pin extending from the second SoW assembly structure and at least partially located in the first slot, a second pin extending from the second SoW assembly structure and at least partially located in the second slot, and a third pin extending from the second SoW assembly structure and at least partially located in the third slot. The first and second slots are formed to allow the first and second pins to move along a first axis in one plane, and the third slot is formed to allow the third pin to move along a second axis in one plane, the second axis being different from the first axis.

[0008] In one embodiment, a first SoW assembly structure is stacked with the SoW.

[0009] In one embodiment, the second coefficient of thermal expansion is greater than the first coefficient of thermal expansion.

[0010] In one embodiment, the first SoW assembly structure comprises a SoW. The SoW assembly may further include a reinforcing functional section coupled to the SoW. The reinforcing functional section may include an opening that aligns with the first slot, the size of which the opening may be smaller than the size of the first slot.

[0011] In one embodiment, the first axis and the second axis are substantially perpendicular to each other.

[0012] In one embodiment, the first slot comprises an elliptical slot configured to receive a first pin, with the major axis of the elliptical slot of the first slot extending along the first axis. The third slot may include an elliptical slot configured to receive a third pin, with the major axis of the elliptical slot of the third slot extending along the second axis.

[0013] In one embodiment, the second SoW assembly structure includes a heat dissipation structure.

[0014] In one embodiment, the first SoW assembly structure may include three or fewer slots configured to receive pins extending from the second SoW assembly structure.

[0015] In one embodiment, a wafer is disclosed, which includes an alignment structure for aligning the wafer with elements stacked perpendicularly on the wafer. The wafer may include a first slot formed at a first location on the wafer. The first slot is configured to mate with a first pin to align the wafer and the element along a first axis. The first slot is shaped to allow the wafer to move along the first axis when the first slot and the first pin are engaged. The wafer may include a second slot formed at a second location on the wafer, different from the first location. The second slot is configured to mate with a second pin to align the wafer and the element along a first axis. The wafer may include a third slot formed at a third location on the wafer, different from the first and second locations. The third slot is configured to mate with a third pin to align the wafer and the element along a second axis different from the first axis.

[0016] In one embodiment, the wafer includes a material having a coefficient of thermal expansion lower than the coefficient of thermal expansion of the element material.

[0017] In one embodiment, the first axis and the second axis are substantially perpendicular to each other.

[0018] In one embodiment, the first slot includes an oval slot configured to receive a first pin, and a major axis of the oval slot of the first slot extends along a first axis. The third alignment slot includes an oval slot configured to receive a third pin, and a major axis of the oval slot of the third slot extends along a second axis.

[0019] In one embodiment, the wafer further includes a reinforcing functional part thereon. The reinforcing functional part can include an opening that aligns with the first slot. The size of the opening of the reinforcing functional part can be made smaller than the size of the first slot such that the first pin is prevented from physically contacting the wafer.

[0020] In one embodiment, the wafer comprises a plurality of integrated circuit dies.

Brief Description of the Drawings

[0021] Here, specific implementations will be described with reference to the following drawings given by way of example and not limitation.

[0022] [Figure 1A] It is a decomposition diagram of a processing system.

[0023] [Figure 1B] It is an assembly diagram of the processing system of FIG. 1A.

[0024] [Figure 2A] It is a schematic perspective view of a system-on-wafer (SoW) according to one embodiment.

[0025] [Figure 2B] It is an enlarged view of a part of the SoW illustrated in FIG. 2A.

[0026] [Figure 3] It is a schematic perspective view of a heat dissipation structure according to one embodiment.

[0027] [Figure 4] A top view of an alignment structure according to one embodiment is shown.

[0028] [Figure 5A] This is a schematic perspective view of a reinforcing function unit according to one embodiment.

[0029] [Figure 5B] This is a schematic top view of an alignment function unit according to one embodiment.

[0030] [Figure 5C] This is a schematic cross-sectional view of an assembly including an alignment structure according to one embodiment.

[0031] [Figure 6A] This is a schematic perspective view of an input / output (I / O) frame according to one embodiment.

[0032] [Figure 6B] This is a schematic perspective view of a cooling system according to one embodiment. [Modes for carrying out the invention]

[0033] The following detailed descriptions of specific embodiments present various descriptions of those specific embodiments. However, the innovations described herein can be embodied in numerous different ways, for example, as based on and encompassed by the claims. In this description, similar reference numbers and / or terms refer to drawings in which identical or functionally similar elements may be shown. It should be understood that the elements shown in the drawings are not necessarily drawn to scale. Furthermore, it should be understood that a particular embodiment may include more elements and / or subsets of elements shown in the drawings than those shown. Moreover, some embodiments may incorporate any suitable combination of features from two or more drawings.

[0034] A system-on-wafer (SoW) assembly may include the SoW and a heat dissipation structure coupled to the SoW. The SoW may include an array of integrated circuit dies. The integrated circuit dies in the SoW can generate heat during operation. The heat dissipation structure can dissipate the heat generated in the SoW. In some applications, it may be important to align the SoW with the heat dissipation structure with relatively high precision. Locking pins can be used to ensure that the SoW and the heat dissipation structure are aligned with each other. However, locking pins may damage the SoW due to a mismatch between the coefficient of thermal expansion (CTE) of the SoW and the CTE of the heat dissipation structure.

[0035] Embodiments disclosed herein relate to SoW assemblies including alignment structures for aligning stacked SoW assembly structures that can achieve relatively high-precision alignment while preventing and / or mitigating damage to elements due to CTE mismatch. The SoW assembly structure may be referred to as an element. The alignment structure may include alignment slots and pins positioned within the alignment slots. The alignment slots of the alignment structure disclosed herein consist of three slots. The alignment structure disclosed herein can align a first element in a processing system with a second element stacked on the first element. For example, the first element may comprise a SoW, and the second element may comprise a heat dissipation structure. As another example, the first element may comprise a cooling system, and the second element may comprise an input / output (I / O) frame. Thus, the thermal system may include one of the stacked elements (e.g., a heat dissipation structure or a cooling system). Both the first and second elements are SoW assembly structures. In some embodiments, alignment slots can be formed within or with the SoW, and pins can be positioned on or with a heat dissipation structure stacked on the SoW. The alignment structure may include reinforcing components that protect the SoW from the pins.

[0036] Figures 1A and 1B show a processing system 10 according to an aspect of the present disclosure. Figure 1A is an exploded view of the processing system 10. Figure 1B is an assembled view of the processing system 10. Features of this disclosure, such as wafer alignment structures, can be implemented in the processing system 10 and / or any other suitable processing system. Features of this disclosure can be implemented in any system comprising two or more elements having different CTEs. The processing system 10 can have a high computation density, and the heat dissipation generated by the processing system 10 can significantly affect the performance of the processing system 10. The processing system 10 can perform trillions of operations per second in a particular application. The processing system 10 can be used in and / or specifically configured for high-performance computing and / or computationally intensive applications such as neural network training and / or processing, machine learning, and artificial intelligence. The processing system 10 can provide redundancy. In several applications, the processing system 10 may be used for neural network training to generate data for use by an autopilot system of a vehicle (e.g., an automobile), to implement other autonomous vehicle functions, or to implement advanced driver-assistance system (ADAS) functions.

[0037] As shown in Figure 1A, the processing system 10 includes a heat dissipation structure 12, a SoW 14, an input / output (I / O) frame 15, a voltage regulation module (VRM) 16, a cooling system 18, and a control broad 19. In the processing system 10, the thermal system includes the heat dissipation structure 12 and the cooling system 18. Each of the illustrated elements of the processing system is an SoW assembly structure. Figure 1B shows the processing system 10 upside down compared to Figure 1A. In Figure 1B, the processing system 10 is shown without the control board 19. The heat dissipation structure 12 and the SoW 14 can be stacked vertically and aligned horizontally using an alignment structure which may include an alignment function and alignment pins. The alignment structure will be described in detail in relation to later drawings.

[0038] The heat dissipation structure 12 can dissipate heat from the SoW 14. The heat dissipation structure 12 may include a heat spreader. Such a heat spreader may include a metal plate. Alternatively, or in addition to this, the heat dissipation structure 12 may include a heat sink. The heat dissipation structure 12 may include any suitable material having desirable heat dissipation properties. A thermal interface material may be included between the heat dissipation structure 12 and the SoW 14 to reduce and / or minimize heat transfer resistance.

[0039] SoW14 can include an array of integrated circuit (IC) dies. The IC dies can be embedded in the molding material. SoW14 can have a high computational density. The IC dies can be semiconductor dies, such as silicon dies. The array of IC dies can include any appropriate number of IC dies. For example, an array of IC dies can include 16, 25, 36, or 49 IC dies. SoW14 can be, for example, an integrated fan-out (InFO) wafer. An InFO wafer can include multiple routing layers on the array of IC dies. For example, an InFO wafer can include 4, 5, 6, 8, or 10 routing layers in a particular application. The routing layers on an InFO wafer can provide signal connectivity between IC dies and / or to external components. SoW14 can have a relatively large diameter, such as in the range of 10 to 15 inches. As an example, SoW14 can have a diameter of 12 inches.

[0040] The I / O frame 15 can contribute to the structural integrity of the processing system 10. The I / O frame 15 can support the VRM 16 and hold the VRM 16 in place.

[0041] The VRM16 may be positioned such that each VRM is stacked with the IC die of the SoW14. In the processing system 10, high-density packing of the VRM16 is present. Therefore, the VRM16 can consume considerable power and generate heat. The VRM16 is configured to receive a direct current (DC) supply voltage and supply a lower output voltage to the corresponding IC die of the SoW14.

[0042] The cooling system 18 can perform active cooling for the VRM 16. The cooling system 18 can perform active cooling for the control board 19. The cooling system 18 may include metal having channels for the flow of heat transfer fluid. In the assembled processing system 10, the cooling system 18 can be bolted to the heat dissipation structure 12. This can provide structural support for the SoW 14 and / or reduce the possibility of damage to the SoW 14. A thermal interface material may be included between the cooling system 18 and the control board 19 to reduce and / or minimize heat transfer resistance.

[0043] The control board 19 may include electrical components. The electronic components of the control board 19 may supply control signals for the VRM 16. The control board 19 may include electronic components for controlling the operation of the SoW 14.

[0044] Figure 2A is a schematic perspective view of SoW14 according to one embodiment. Figure 2B is an enlarged view of a portion of SoW14 shown in Figure 2A, indicated by a dashed rectangle. Figure 3 is a schematic perspective view of the heat dissipation structure 12. SoW14 and heat dissipation structure 12 can be included in a processing system such as the processing system 10 shown in Figures 1A and 1B.

[0045] In some embodiments, the heat dissipation structure 12 may include a material having a relatively high coefficient of thermal expansion (CTE). For example, the heat dissipation structure 12 may include copper (Cu) and / or aluminum (Al). In some embodiments, the heat dissipation structure 12 may include a material having a CTE in the range of 10 ppm / °C to 20 ppm / °C. For example, the heat dissipation structure 12 may include copper having a CTE of about 17 ppm / °C. In some embodiments, the SoW 14 may include a material having a relatively low CTE coefficient. For example, the SoW 14 may comprise a silicon (Si) wafer. In some embodiments, the SoW 14 may include a material having a CTE in the range of 1 ppm / °C to 10 ppm / °C. For example, silicon may have a CTE of about 2.6 ppm / °C. In some embodiments, the CTE of the heat dissipation structure 12 may be 2 to 7 times greater than the CTE of the SoW 14.

[0046] The SoW14 may include an array of integrated circuit (IC) dies 22 located on a wafer 24. In some embodiments, the IC dies 22 may include sensor dies, memory dies, application-specific integrated circuit (ASIC) dies, and / or micro-electromechanical system (MEMS) dies. In some embodiments, the IC dies 22 may communicate with each other within the SoW14 via redistribution layers (RDLs) formed on the IC dies 22. The RDLs and / or other electrical connections within the SoW14 may beneficially provide, for example, relatively low latency, relatively high bandwidth density, and / or relatively low power distribution network (PDN) impedance in communication between the IC dies 22. During operation, the SoW14 generates heat.

[0047] To obtain desirable heat dissipation, it may be beneficial to align the SoW14 and the heat dissipation structure 12 with relatively high precision. For example, it may be beneficial to align the SoW14 and the heat dissipation structure 12 such that the reference point 26 (e.g., center point) of the SoW14 aligns with the reference point 32 (e.g., center point) of the heat dissipation structure 12. The reference point 26 of the SoW14 can be aligned with the reference point 32 of the heat dissipation structure 12 within a tolerance range of 100 to 200 microns. For example, the reference point 26 of the SoW14 can be aligned with the reference point 32 of the heat dissipation structure 12 within a tolerance range of 100 to 150 microns, 150 to 200 microns, or 125 to 175 microns. However, the mechanism for locking the heat dissipation structure 12 and the SoW14 in place may damage the heat dissipation structure 12 and / or the SoW14 due to a CTE mismatch.

[0048] The heat dissipation structure 12 and SoW 14 can be stacked vertically. The heat dissipation structure 12 and SoW 14 can be aligned horizontally using an alignment structure. The alignment structure may comprise slots 28a, 28b, 28c and alignment pins 34a, 34b, 34c. For example, SoW 14 may have an alignment function section 28 that includes first to third holes or slots 28a, 28b, 28c, as shown in Figures 2A and 2B. Slots 28a, 28b, 28c are examples of the alignment function section of SoW 14. As shown in Figure 3, first to third pins 34a, 34b, 34c may extend from the heat dissipation structure 12. In some embodiments, the heat dissipation structure 12 and the first to third pins 34a, 34b, 34c may be formed separately and assembled together. Slots 28a, 28b, and 28c can mate with or receive the first to third pins 34a, 34b, and 34c, respectively. The alignment structure can achieve alignment with relatively high precision while preventing and / or mitigating damage to elements caused by CTE mismatch between the heat dissipation structure 12 and the SoW 14.

[0049] The illustrated embodiment shows slots 28a, 28b, 28c within the SoW 14 and pins 34a, 34b, 34c extending from the heat dissipation structure 12; however, in some other applications, the slots can be formed in the heat dissipation structure 12 and the pins can extend from the SoW 14. Support structures (not shown) can be provided around the pins extending from the SoW 14 so that the pins are coupled more strongly and / or more securely to the SoW 14 than if there were no support structures. Any suitable principles and advantages disclosed herein can be utilized when aligning two or more elements having different CTEs.

[0050] Figure 4 shows a plan view of an alignment structure comprising a first slot 28a and a first pin 34a positioned within the slot 28a. The alignment structure may also include second and third slots 34b and 34c and second and third pins 28b and 28b positioned within the respective second and third slots 28b and 28c in the same or substantially similar manner as shown in Figure 4.

[0051] The first slot 28a can be used to allow the first pin 34a to shift or move along the first horizontal axis 40 (see Figure 2A). The second slot 28b can be used to allow the second pin 34b to shift or move along the first horizontal axis 40 (see Figure 2A). The third slot 28c can be used to allow the third pin 34c to shift or move along the second horizontal axis 42 (see Figure 2A) (see Figure 2A). The first horizontal axis 40 and the second horizontal axis 42 are non-parallel to each other. For example, the first horizontal axis 40 and the second horizontal axis 42 may be perpendicular to each other, as shown in Figure 2A. The first horizontal axis 40 and the second horizontal axis 42 may be substantially perpendicular to each other, such as being oriented at angles in the range of 85° to 95° relative to each other. The first horizontal axis 40 and the second horizontal axis 42 are examples of two axes in one plane.

[0052] The first to third slots 28a, 28b, and 28c can take any suitable shape. In some embodiments, the first to third slots 28a, 28b, and 28c may have elliptical or oblong holes. In such embodiments, the major axis 36 of the elliptical hole in the first slot 28a and the major axis 36 of the elliptical hole in the second slot 28b may extend along the first horizontal axis 40, and the major axis 36 of the elliptical hole in the third slot 28c may extend along the second horizontal axis 42. As shown in Figure 4, the first to third pins 34a, 34b, and 34c may be smaller than the first to third slots 28a, 28b, and 28c. In some embodiments, the pins 34a, 34b, and 34c can be configured as pins having a circular cross-section that fits relatively tightly along the minor axis 38 of the elliptical holes in the slots 28a, 28b, and 28c, while having a gap along the major axis 36 of the elliptical holes in the slots 28a, 28b, and 28c, thereby allowing the pins 34a, 34b, and 34c to move along the major axis 36. Thus, the pins 34a, 34b, and 34c can move to compensate for the CTE mismatch between the heat dissipation structure 12 and the SoW 14, thereby preventing and / or mitigating damage to the heat dissipation structure 12 and / or the SoW 14. At the same time, the pins 34a, 34b, and 34c, together with the slots 28a, 28b, and 28c, can maintain a relatively high degree of precision in the alignment between the heat dissipation structure 12 and the SoW 14.

[0053] The three slots 28a, 28b, and 28c and their respective three pins 34a, 34b, and 34c allow the heat dissipation structure 12 and the SoW 14 to be aligned horizontally with each other. For example, the first and second slots 28a, 28b and the first and second pins 34a, 34b can contribute to the alignment of the heat dissipation structure 12 and the SoW 14 along one horizontal axis, while the third slot 28c and the third pin 34c can contribute to the alignment of the heat dissipation structure 12 and the SoW 14 along the other horizontal axis. Therefore, when the pins 34a, 34b, and 34c move to compensate for the CTE mismatch between the heat dissipation structure 12 and the SoW 14, the alignment between the reference points 26 and 32 of the heat dissipation structure 12 and the SoW 14 can be sufficiently maintained.

[0054] An alignment structure with three slots 28a, 28b, and 28c and their respective pins 34a, 34b, and 34c may be more beneficial than one with four or more slots and their respective pins. For example, an alignment structure with three slots and their respective pins allows the heat dissipation structure 12 and SoW 14 to move relative to each other in both horizontal and vertical directions to maintain alignment. In contrast, an alignment structure with four or more slots may prevent the heat dissipation structure 12 and SoW 14 from moving relative to each other in two orthogonal directions. Therefore, with four or more slots and their respective pins, the heat dissipation structure 12 and / or SoW 14 may become misaligned due to a CTE mismatch between the heat dissipation structure 12 and SoW 14. Using four slots and corresponding pins may excessively restrict the SoW 14 and heat dissipation structure 12, thereby allowing thermal expansion due to the CTE mismatch to cause misalignment or damage to the SoW 14 and / or heat dissipation structure 12.

[0055] On the other hand, in an alignment structure with two slots and their respective pins, the degrees of freedom for the heat dissipation structure 12 and the SoW 14 to move relative to each other may become too large, potentially causing misalignment between the heat dissipation structure 12 and the SoW 14. Using two slots and corresponding pins may restrict the SoW 14 and the heat dissipation structure 12, which could lead to thermal expansion due to CTE mismatch causing misalignment or damage to the SoW 14 and / or the heat dissipation structure 12.

[0056] The sizes of slots 28a, 28b, and 28c can be determined at least in part based on manufacturing tolerances during the lamination process and CTE mismatch between the heat dissipation structure 12 and the SoW 14. For example, the sizes of slots 28a, 28b, and 28c can be determined to give sufficient space for pins 34a, 34b, and 34c to move along the long axis 36 without contacting the ends of slots 28a, 28b, and 28c.

[0057] The first and second slots 28a and 28b have a length along the first horizontal axis 40 and a width along an axis perpendicular to the first horizontal axis 40 (e.g., the second horizontal axis 42). The third slot 28c has a length along the second horizontal axis 42 and a width along an axis perpendicular to the second horizontal axis 42 (e.g., the first horizontal axis 40). In some embodiments, the length of slots 28a, 28b, and 28c may be about 1.5 times the diameter of pins 34a, 34b, and 34c. For example, the length of slots 28a, 28b, and 28c may be about 1.1 to 2, about 1.4 to 2, about 1.1 to 1.7, or about 1.4 to 1.7 times the diameter of pins 34a, 34b, and 34c. In some embodiments, the width of slots 28a, 28b, and 28c can be approximately the same size as the diameter of pins 34a, 34b, and 34c.

[0058] Figure 5A is a schematic perspective view of a reinforcing function 50 according to one embodiment. The reinforcing function 50 can be implemented using any of the alignment structures disclosed herein. Figure 5B is a schematic top view of an alignment function 28 including a slot 28a in which the SoW 14 and the reinforcing function 50 positioned on the SoW 14 are formed. Two or more reinforcing function 50 may be provided on other parts of the SoW 14. For example, two further reinforcing function 50 can be positioned above slots 28b, 28c and aligned with slots 28b, 28c (see Figure 2A). Figure 5C is a schematic cross-sectional side view of an assembly including an alignment structure. As shown in Figure 5C, the alignment structure includes an alignment function 28 and a pin 34 extending from a heat dissipation structure 12.

[0059] The reinforcing function section 50 may include a material that is more durable and / or rigid than the material of the SoW 14. In some embodiments, the reinforcing function section 50 may include a ceramic, a ceramic-like material, or an organic material. In some embodiments, the reinforcing function section 50 may include a material having a CTE similar to that of the SoW 14. For example, the CTE of the SoW can be closer to that of the reinforcing function section 50 than the CTE of the heat dissipation structure 12.

[0060] The reinforcing function section 50 may be provided with an opening 52. The size of the opening 52 may be less than or equal to the size of the slot 28a. The shape of the opening 52 may be the same as or similar to the shape of the slot 28a. For example, the opening 52 may be an elliptical or oblong hole. When the pin 34a moves together within the slot 28a, the reinforcing function section 50 can prevent the pin 34 from coming into contact with the SoW 14, thereby protecting the SoW 14 from damage by the pin 34. Therefore, the reinforcing function section 50 can reduce or eliminate the risk of the SoW 14 being scraped and cracked by the contact force between the pin and the slot.

[0061] In some embodiments, the reinforcing section 50 can be bonded to the SoW 14 by adhesive 54. The reinforcing section 50 can serve as an alignment board. In some embodiments, the reinforcing section 50 can be bonded to the SoW 14 by a ball grid array (BGA). Such a BGA can be aligned with pads on the SoW 14. The reinforcing section 50 can be optically aligned with the SoW. After this optical alignment, an underfill can be provided for strength and reliability. The adhesive 54 may include the underfill.

[0062] While embodiments disclosed herein may relate to alignment structures for aligning a SoW with a heat dissipation structure, any suitable principles and advantages disclosed herein can be applied to alignment structures at any location within a processing system, such as between an I / O frame 15 and a cooling system 18 (see Figures 1A, 1B, 6A, and 6B). Any suitable principles and advantages disclosed herein in relation to alignment structures can be applied to maintain precise alignment between two different elements having different CTEs within a SoW assembly.

[0063] Figure 6A is a schematic perspective view of an I / O frame 15 according to one embodiment. Figure 6B is a schematic perspective view of a cooling system 18 according to one embodiment. The I / O frame 15 can receive pins 60 through an opening that penetrates it. The cooling system 18 may be provided with slots 62a, 62b, and 62c. The slots 62a, 62b, and 62c may be configured to mate with or receive pins 60 in order to align the I / O frame 15 and the cooling system 18. Any suitable principles and advantages disclosed herein can be applied to pins 60 and slots 62a, 62b, and 62c. In some other embodiments, the I / O frame 15 may be provided with slots and the cooling system may be provided with pins.

[0064] The alignment structures disclosed herein can be used to align two or more SoW assembly structures within a processing system (e.g., processing system 10 shown in Figure 1A). The alignment structures disclosed herein can be used to align first and second SoW assembly structures within a processing system having different CTEs. For example, the first SoW assembly structure may be SoW 14 and the second SoW assembly structure may be a heat dissipation structure 12. As another example, the first SoW assembly structure may be a cooling system 18 and the second SoW assembly structure may be an I / O frame 15.

[0065] Unless the context clearly requires otherwise, throughout the specification and claims, words such as “comprise,” “comprising,” “include,” and “including” should be interpreted in a comprehensive sense, as opposed to an exclusive or exhaustive sense, i.e., “including but not limited to.” The term “combined” as commonly used herein refers to two or more elements that can be directly joined or joined by one or more intermediate elements. Similarly, the term “connected” as commonly used herein refers to two or more elements that can be directly joined or joined by one or more intermediate elements. Furthermore, the words “herein,” “below,” “above,” and words with similar meanings, when used in this application, refer to the entire application and not to any particular part thereof. Where the context allows, words in the above detailed description that use singular or plural numbers may also include plural or singular numbers, respectively. The word "or" in relation to a list of two or more items encompasses all of the following interpretations of the word: any of the items in the list, all of the items in the list, and any combination of the items in the list.

[0066] Furthermore, the conditional language used herein, in particular "can," "could," "might," "may," "eg," "for example," and "such as," unless otherwise specifically stated or understood to have a different meaning in the context in which they are used, generally intends to convey that certain embodiments include certain features, elements, and / or states, while other embodiments do not. Thus, such conditional language is not generally intended to suggest that features, elements, and / or states are required in any way for one or more embodiments.

[0067] The above description is provided in relation to a specific embodiment. However, the above illustrative description is not intended to be exhaustive or to limit the invention to the form described. Many modifications and variations are possible in light of the above teachings. This will enable those skilled in the art to best utilize the technology and various embodiments with various modifications suitable for various applications.

[0068] While the present disclosure and embodiments have been described in relation to the accompanying drawings, various changes and modifications will be apparent to those skilled in the art. Such changes and modifications should be understood to be within the scope of the present disclosure.

Claims

1. A system-on-wafer (SoW) assembly, A first SoW assembly structure including a first slot in a first position, a second slot in a second position, and a third slot in a third position, A second SoW assembly structure stacked with the first SoW assembly structure, the second SoW assembly structure having a first pin extending from the second SoW assembly structure and at least partially disposed within the first slot, a second pin extending from the second SoW assembly structure and at least partially disposed within the second slot, and a third pin extending from the second SoW assembly structure and at least partially disposed within the third slot, The first slot and the second slot are formed to allow the first pin and the second pin to move along a first axis in one plane, and the third slot is formed to allow the third pin to move along a second axis different from the first axis in the plane. A SoW assembly in which either the first SoW assembly structure or the second SoW assembly structure is included in a thermal system configured to cool the SoW.

2. The SoW assembly according to claim 1, wherein the first SoW assembly structure comprises the SoW, and the second SoW assembly structure comprises a heat dissipation structure.

3. The SoW assembly according to claim 2, further comprising a reinforcing function portion coupled to the SoW, wherein the reinforcing function portion has an opening that aligns with the first slot, and the size of the opening is smaller than the size of the first slot such that the reinforcing function portion prevents the first pin from physically contacting the SoW.

4. The SoW assembly according to claim 3, wherein the opening has an elliptical shape.

5. The SoW assembly according to claim 1, wherein the first axis is substantially perpendicular to the second axis.

6. The SoW assembly according to claim 1, wherein the first SoW assembly structure comprises a cooling system, the second SoW assembly structure comprises an input / output frame, and the first and second SoW assembly structures are stacked with the SoW.

7. A system-on-wafer (SoW) assembly, A first SoW assembly structure having a first coefficient of thermal expansion, comprising a first slot in a first position, a second slot in a second position, and a third slot in a third position, A second SoW assembly structure is laminated on the first SoW assembly structure, and the second SoW assembly structure has a second coefficient of thermal expansion different from that of the first SoW assembly structure, and comprises a first pin extending from the second SoW assembly structure and at least partially disposed within the first slot, a second pin extending from the second SoW assembly structure and at least partially disposed within the second slot, and a third pin extending from the second SoW assembly structure and at least partially disposed within the third slot, SoW assembly wherein the first slot and the second slot are formed to allow the first pin and the second pin to move along a first axis in one plane, and the third slot is formed to allow the third pin to move along a second axis in the plane, the second axis being different from the first axis.

8. The SoW assembly according to claim 7, wherein the first SoW assembly structure is stacked with the SoW.

9. The SoW assembly according to claim 7, wherein the second coefficient of thermal expansion is greater than the first coefficient of thermal expansion.

10. The SoW assembly according to claim 7, wherein the first SoW assembly structure comprises a SoW.

11. The SoW assembly according to claim 10, further comprising a reinforcing functional part coupled to the SoW.

12. The SoW assembly according to claim 11, wherein the reinforcing function portion has an opening that aligns with the first slot, and the size of the opening is smaller than the size of the first slot.

13. The SoW assembly according to claim 7, wherein the first axis and the second axis are substantially perpendicular to each other.

14. The SoW assembly according to claim 7, wherein the first slot comprises an elliptical slot configured to receive the first pin, and the major axis of the elliptical slot of the first slot extends along the first axis.

15. The SoW assembly according to claim 14, wherein the third slot comprises an elliptical slot configured to receive the third pin, and the major axis of the elliptical slot of the third slot extends along the second axis.

16. The SoW assembly according to claim 7, wherein the second SoW assembly structure comprises a heat dissipation structure.

17. The SoW assembly according to claim 7, wherein the first SoW assembly structure includes three or fewer slots configured to receive pins extending from the second SoW assembly structure.

18. A wafer having an alignment structure for aligning the wafer with elements stacked vertically on the wafer, A first slot formed at a first position on the wafer, configured to engage with a first pin to align the wafer and the element along a first axis, and molded to allow the wafer to move along the first axis when the first slot and the first pin are engaged, A second slot formed at a second position on the wafer, different from the first position, and configured to engage with a second pin to align the wafer and the element along the first axis, A wafer comprising: a third slot formed at a third position on the wafer different from the first and second positions, the third slot being configured to engage with a third pin to align the wafer and the element along a second axis different from the first axis.

19. The wafer according to claim 18, comprising a material having a coefficient of thermal expansion lower than the coefficient of thermal expansion of the material of the aforementioned element.

20. The wafer according to claim 18, wherein the first axis and the second axis are substantially perpendicular to each other.

21. The wafer according to claim 18, wherein the first slot comprises an elliptical slot configured to receive the first pin, the major axis of the elliptical slot of the first slot extends along the first axis, and the third slot comprises an elliptical slot configured to receive the third pin, the major axis of the elliptical slot of the third slot extends along the second axis.

22. The wafer according to claim 18, further comprising a reinforcing function portion on the wafer, the reinforcing function portion having an opening that aligns with the first slot, the size of the opening in the reinforcing function portion being smaller than the size of the first slot such that the reinforcing function portion is configured to prevent the first pin from physically contacting the wafer.

23. The wafer according to claim 18, wherein the wafer comprises a plurality of integrated circuit dies.

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