Electronic assemblies and methods of manufacturing the same

Abstract

Wafer components and related manufacturing methods are disclosed. Such components and methods can take into account different heights of electronic modules positioned on a wafer. In one embodiment, a wafer component includes a cooling system, a wafer, a first electronic module, a second electronic module, and a height adjustment structure. A first thermal interface material (TIM) may be disposed between the first electronic module and a first portion of the cooling system. A second TIM may be disposed between the second electronic module and a second portion of the cooling system. The height adjustment structure can compensate for the height difference between the first and second electronic modules. Other wafer components and manufacturing methods are disclosed.

Description

Technical Field

[0001] This invention relates generally to electronic components and methods for manufacturing electronic components. [Mutually] [close] [state] [please] [Cross-references] [] [This invention claims a document filed on July 7, 2021, entitled "..." “ELECTRONIC ASSEMBLIES AND METHODS OF The benefit of U.S. Provisional Patent Application No. 63 / 219,205, “Manufacture the Same,” the disclosure of which is incorporated herein by reference in its entirety for all purposes. Prior Technology

[0002] A system-on-wafer (SoW) component may include a SoW and a heat dissipation structure coupled to the SoW. A voltage regulation module (VRM) and a thermal interface material may be present between the heat dissipation structure and the SoW. Significant stress is applied when the SoW and the heat dissipation structure are combined. Summary of the Invention

[0003] [Image of a wafer assembly] A wafer assembly is disclosed in one embodiment. The assembly includes a cooling system, a wafer, a first electronic module, a second electronic module, and a height adjustment structure. The first electronic module is mounted at a first location on the wafer and coupled to a first portion of the cooling system. The first electronic module and the first portion of the cooling system are positioned such that a first thermal interface material (TIM) is disposed between the first electronic module and the first portion of the cooling system. The second electronic module is mounted at a second location on the wafer, different from the first location, and coupled to a second portion of the cooling system. The second electronic module and the second portion of the cooling system are positioned such that a second TIM is disposed between the second electronic module and the second portion of the cooling system. The height adjustment structure is disposed between the first location on the wafer and the first portion of the cooling system. The height adjustment structure is configured to compensate for the height difference between the first electronic module and the second electronic module. In one embodiment, the first electronic module is a voltage regulation module (VRM). In one embodiment, the height adjustment structure includes a crown disposed on the first electronic module. In one embodiment, the height adjustment structure includes a protrusion extending from a first part of the cooling system. In one embodiment, the component further includes a second height adjustment structure disposed between a second location on the wafer and a second portion of the cooling system. The height of the second height adjustment structure differs from the height of the first height adjustment structure. In one embodiment, the height adjustment structure includes a portion of the first TIM. In one embodiment, the component further includes a heat dissipation structure positioned such that the wafer is located between the cooling system and the heat dissipation structure. In one embodiment, a wafer assembly is disclosed. The assembly includes a wafer having a central region and an edge region surrounding the central region. The assembly includes a plurality of electronic modules mounted on the wafer at different heights, such that the average height of a first group of electronic modules located in the central region is greater than the average height of a second group of electronic modules located in the edge region. The assembly includes a cooling system coupled to the plurality of electronic modules. The cooling system and the plurality of electronic modules are positioned such that a thermal interface material (TIM) is disposed between the cooling system and the plurality of electronic modules. The wafer is curved such that the edge region of the wafer is closer to the cooling system than the central region of the wafer. In one embodiment, the first group of electronic modules has a height greater than that of the second group of electronic modules. In one embodiment, the component further includes a heat dissipation structure positioned such that the wafer is located between the cooling system and the heat dissipation structure. In one embodiment, the plurality of electronic modules includes a plurality of voltage regulation modules (VRMs). In one embodiment, a method for manufacturing a wafer assembly is disclosed. The method includes: selecting a first set of electronic modules and a second set of electronic modules from a plurality of electronic modules, such that the height variation of the first set of electronic modules and the height variation of the second set of electronic modules are both less than the height variation of the plurality of electronic modules. The method includes: mounting the first set of electronic modules on a first wafer and mounting the second set of electronic modules on a second wafer. The method includes: coupling a first cooling system and the first set of electronic modules such that a first thermal interface material is located between the first cooling system and the first set of electronic modules. The method includes: coupling a second cooling system and the second set of electronic modules such that a second thermal interface material is located between the second cooling system and the second set of electronic modules. In one embodiment, the plurality of electronic modules includes a plurality of voltage regulation modules (VRMs). In one embodiment, the first wafer includes an integrated circuit die aligned with a corresponding electronic module in a first set of electronic modules. In one embodiment, the height variation of the first group of electronic modules and the height variation of the second group of electronic modules are each less than half of the height variation of the plurality of electronic modules. In one embodiment, coupling the first cooling system and the first set of electronic modules includes: applying a force to the cooling system to compress the first thermal interface material. In one embodiment, the method further includes: providing a first heat dissipation structure such that a first wafer is located between a first cooling system and the first heat dissipation structure. In one embodiment, the method further includes: securing the first heat dissipation structure and the first cooling system with a first fastener, and securing the second heat dissipation structure and the second cooling system with a second fastener. The second fastener is longer than the first fastener. In one embodiment, the method further includes: selecting a third set of electronic modules from the plurality of electronic modules such that the height variation of the third set of electronic modules is less than the height variation of the plurality of electronic modules; mounting the third set of electronic modules on a third wafer; and coupling a third cooling system and the third set of electronic modules such that a third thermal interface material is located between the third cooling system and the third set of electronic modules. In one embodiment, mounting the first set of electronic modules on a first wafer includes: mounting a first sub-group of the first set of electronic modules in a central region of the first wafer, and mounting a second sub-group of the first set of electronic modules in an edge region of the first wafer surrounding the central region. The first sub-group of the electronic modules has an average height greater than the average height of the second sub-group of the electronic modules. The wafer is curved such that the edge region is spaced from the cooling system at a smaller distance than the central region. Simple Explanation of the Diagram

[0004] The specific implementation will now be described with reference to the following diagram, which is provided as an example and not as a limitation. [Figure 1] shows a schematic cross-sectional side view of the SoW assembly before the cooling system is coupled to the VRM on the system-on-wafer (SoW). [Figure 2] shows a schematic cross-sectional side view of the SoW assembly of Figure 1 after the cooling system is coupled to the VRM. [Figure 3] is a schematic cross-sectional side view of the SoW component according to an embodiment. [Figure 4A] shows a schematic cross-sectional side view of the SoW assembly before the cooling system is coupled to the first set of VRMs on the SoW, according to an embodiment. [Figure 4B] shows a schematic cross-sectional side view of the SoW assembly before the cooling system is coupled to the second set of VRMs on the SoW, according to another embodiment. [Figure 4C] shows a schematic cross-sectional side view of the SoW assembly of Figure 4A after the cooling system is coupled to the first set of VRMs on the SoW. [Figure 4D] shows a schematic cross-sectional side view of the SoW assembly of Figure 4B after the cooling system is coupled to the second set of VRMs on the SoW. [Figure 5A] shows a schematic cross-sectional side view of a SoW assembly with a height adjustment structure before the height adjustment structure is thinned, according to an embodiment. [Figure 5B] shows a schematic cross-sectional side view of the SoW assembly of Figure 5A after the height adjustment structure has been thinned and before the cooling system has been coupled to the VRM on the SoW. [Figure 5C] shows a schematic cross-sectional side view of the SoW assembly of Figure 5B after the cooling system is coupled to the VRM on the SoW. [Figure 6A] shows a schematic cross-sectional side view of a SoW assembly including a cooling system with a highly adjustable structure before coupling the cooling system to the VRM on the SoW, according to an embodiment. [Figure 6B] shows a schematic cross-sectional side view of the SoW assembly of Figure 6A after the cooling system is coupled to the first set of VRMs on the SoW. [Figure 7A] shows a schematic cross-sectional side view of the SoW component and a graph showing the measurement results associated with the SoW component. [Figure 7B] shows a schematic cross-sectional side view of the SoW component according to an embodiment, and a graph showing the measurement results associated with the SoW component. [Figure 8] shows a schematic cross-sectional side view of a SoW assembly including a cooling system coupled to a VRM on the SoW via thermal interface material (TIM) layers of different sizes. Implementation

[0005] The following detailed description of certain embodiments presents various descriptions of particular embodiments. However, the innovations described herein can be embodied in many different ways, for example, as defined and covered by the claims. In this description, references are made to drawings, wherein similar reference numerals and / or terms may indicate identical or functionally similar elements. It will be understood that the elements illustrated in the figures are not necessarily drawn to scale. Furthermore, it will be understood that some embodiments may include more elements and / or a subset of the elements illustrated in the figures than are illustrated in the figures. In addition, some embodiments may incorporate any suitable combination of features from two or more figures. System-on-Wafer (SoW) components may include the SoW and a cooling system coupled to it. The SoW may include an array of integrated circuit dies. The SoW may be sensitive to external forces. The SoW and the heat dissipation structure may include an array of electronic modules, such as voltage regulation modules (VRMs), positioned therebetween. A thermal interface material (TIM) may be positioned between the VRM and the heat dissipation structure. Pressure may be applied to couple the SoW and the heat dissipation structure. When the VRM has different heights, non-uniform TIM compression may cause the SoW to experience non-uniform forces, which may damage the SoW. Some VRMs have relatively large variations in height. Reducing or eliminating non-uniform TIM compression associated with such VRMs can reduce the risk of wafer stress and strain. The embodiments disclosed herein relate to SoW (Solar Component) assemblies that compensate for or otherwise account for height differences between multiple VRMs (Variable Residual Components) and methods for manufacturing such SoW assemblies. Such embodiments can prevent and / or mitigate the risk of damage to sensitive elements (e.g., SoW) in a SoW assembly due to uneven pressure applied during assembly. Some embodiments disclosed herein relate to a SoW assembly comprising a SoW, a heat dissipation structure, a TIM (Transformation Injection Mechanism), and a height adjustment structure. The height adjustment structure may be included on or with an electronic module. Alternatively or additionally, the height adjustment structure may be included on or with a cooling system. The height adjustment structure can compensate for height differences between electronic modules (such as VRMs). Some embodiments disclosed herein relate to a SoW assembly comprising multiple VRMs of different heights arranged to reduce the risk of damage to the SoW due to uneven pressure on the SoW. Some embodiments disclosed herein relate to a method of manufacturing a SoW assembly, wherein each has a VRM having a corresponding height within a certain range to reduce uneven pressure applied to the SoW. Such methods may involve binning VRMs by height and using different groups of VRMs in different SoW components, each with fasteners having different fastener heights corresponding to the VRM heights. Figure 1 shows a schematic cross-sectional side view of the SoW assembly 1 before the cooling system 18 is coupled to the VRM 16 on the system-on-wafer (SoW) 14. Figure 2 shows a schematic cross-sectional side view of the SoW assembly 1 after the cooling system 18 is coupled to the VRM 16. As illustrated in Figures 1 and 2, the SoW assembly 1 includes a heat dissipation structure 12, SoW 14, VRM 16, cooling system 18, TIM 20, and TIM 22. SoW component 1 includes a TIM 20 between the cooling system 18 and the VRM 16. The TIM 20 improves thermal conductivity between the cooling system 18 and the VRM 16. The TIM 20 provides adhesion between the cooling system 18 and the VRM 16. As shown in Figure 1, the TIM 20 can be provided to the cooling system 18. SoW 14 and heat dissipation structure 12 can be coupled together, as shown in Figure 2. TIM 22 can be provided between heat dissipation structure 12 and SoW 14. Heat dissipation structure 12 can dissipate heat from SoW 14. Heat dissipation structure 12 may include a heat sink. Such a heat sink may include a metal plate. Alternatively or additionally, heat dissipation structure 12 may include a radiator. Heat dissipation structure 12 may include metals such as copper and / or aluminum. SoW 14 may include an array of integrated circuit (IC) dies. The IC dies may be embedded in a molding material. The IC dies may be semiconductor dies, such as silicon dies. The IC die array may include any suitable number of IC dies. For example, an IC die array may include 16 IC dies, 25 IC dies, 36 IC dies, or 49 IC dies. For example, SoW 14 may be an integrated fan-out (InFO) wafer. The InFO wafer may include multiple wiring layers on the IC die array. For example, in some applications, the InFO wafer may include 4, 5, 6, 8, or 10 wiring layers. The wiring layers of the InFO wafer can provide signal connections between IC dies and / or to external components. VRM 16 can be positioned such that each VRM is stacked with the IC die of SoW 14. In some applications, VRM 16 can consume a considerable amount of power. VRM 16 can be configured to receive a DC supply voltage and supply a lower output voltage to the corresponding IC die of SoW 14. VRM 16 may each have a height. For example, VRM 16a has a height h1a, and VRM 16b has a height h1b. Due to manufacturing tolerances, for example, VRM 16 may have different heights. The average height difference between VRM 16 may be about + / - 300 micrometers. The average difference between VRM 16 may be about + / - 10% of the height of the highest VRM 16a in the SoW assembly 1, such as in the range of about 8% to 12% of the height of the highest VRM 16a. Before the cooling system 18, VRM 16, and SoW 14 are coupled together, the TIM 20 at each VRM 16 may have the same or substantially similar height h2. When the cooling system 18 and SoW 14 are brought together, the highest VRM 16a in the VRM 16 may first contact the corresponding TIM 20a, and the shortest VRM 16b in the VRM 16 may last contact the corresponding TIM 20b. When the cooling system 18 is compressed against the SoW 14 to make contact between the VRM 16 and the TIM 20, the TIM 20a at the highest VRM 16a in the VRM 16 experiences increased compressive force. This compressive force can be transmitted through the VRM 16 to the SoW 14, which can exert uneven pressure on the SoW, potentially damaging it. In some cases, the portion of the SoW in contact with the highest VRM 16a may experience significantly higher compressive force than the portion of the SoW in contact with the shortest VRM 16b, potentially damaging the portion of the SoW in contact with the highest VRM 16a. In some cases, after the SoW 14 and the cooling system 18 are coupled together, the TIM 20a may have a higher density than the TIM 20b, and / or the TIM 20a may have a larger footprint than the TIM 20b. As shown in Figures 1 and 2, SoW 14 can have a warped or curved shape. Utilizing this curvature, the outer edge of SoW 14 is positioned further away from the heat dissipation structure 12 than the middle portion of SoW 14. Therefore, when the VRMs 16 have the same height, the top surface of one VRM in VRM 16 can be lower than the top surface of another VRM in VRM 16, and during the coupling process, one or more of the VRMs 16 can contact one or more corresponding VRMs in TIM 20 before the remaining VRMs 16. When the cooling system 18 is pressed against SoW 14 to make contact between the VRMs 16 and TIM 20, the VRM with a higher top surface than the other VRMs can experience increased compressive forces. These compressive forces can be transmitted through the VRMs 16 to SoW 14, which can damage SoW 14. In other words, during the coupling process used to couple the cooling system 18 to the VRM 16 on the SoW 14, the height difference between the VRM 16 can cause an uneven distribution of compressive force on the SoW 14 and can damage the SoW 14. Cooling system 18 may include any suitable heat dissipation structure. Cooling system 18 may provide active cooling for VRM 16. Active cooling may involve a coolant, such as a liquid coolant, flowing through cooling system 18. Cooling system 18 may include metal having a flow path through which the heat transfer fluid flows. As an example, cooling system 18 may include a machined metal, such as copper. Cooling system 18 may include one or more brazed fin arrays for high cooling efficiency. In the fully assembled SoW assembly 1, cooling system 18 may be bolted to heat dissipation structure 12. Bolting cooling system 18 and heat dissipation structure 12 may provide structural support for SoW 14 and / or reduce the chance of SoW 14 breaking. Figure 3 is a schematic cross-sectional side view of a system-on-wafer (SoW) assembly 3 according to an embodiment. In this embodiment, the VRMs are compartmentalized such that VRMs 16 with similar heights to each other are used in the SoW assembly 3. The higher VRMs are positioned in the central region 30 of the SoW 14 to take into account the curvature of the SoW 14. Unless otherwise noted, the components of the SoW assembly 3 of Figure 3 may be identical or substantially similar to similar components of any SoW assembly disclosed herein. SoW assembly 3 may include a heat dissipation structure 12 and a SoW 14 positioned on the heat dissipation structure 12. A TIM 22 may be present between the heat dissipation structure 12 and the SoW 14. SoW assembly 3 may include a VRM 16 positioned on the SoW 14 and a cooling system 18 positioned on the VRM 16. A TIM 20 may be present between the VRM 16 and the cooling system 18. VRM 16 is selected and positioned on SoW 14 such that the higher VRM is positioned near the central region 30 of SoW 14, and the shorter VRM is positioned near the edge region 32 of SoW 14 to compensate for any warping or bending shape of SoW 14. As shown by dashed lines in Figure 3, the upper surfaces of VRM 16 are at the same or approximately similar height relative to each other. Therefore, when a force is applied to couple the cooling system 18 and SoW 14 together, a substantially uniform, equal, or nearly equal compressive force can be applied to each of the VRM 16 and each corresponding TIM 20. Such a substantially uniform, equal, or nearly equal compressive force can mitigate the risk of damage to SoW 14 due to coupling the cooling system 18 to SoW 14. Although VRM 16 is positioned on SoW 14 in the illustrated embodiment, VRM 16 can be positioned on any suitable carrier or wafer other than SoW 14. Figure 4A shows a schematic cross-sectional side view of the SoW assembly 4 before coupling the cooling system 18 to the first set of VRMs 36 on the SoW 14 according to an embodiment. Figure 4B shows a schematic cross-sectional side view of the SoW assembly 5 before coupling the cooling system 18 to the SoW 14 to the second set of VRMs 38 according to an embodiment. Figure 4C shows a schematic cross-sectional side view of the SoW assembly 4 after coupling the cooling system 18 to the SoW 14 to the first set of VRMs 36. Figure 4D shows a schematic cross-sectional side view of the SoW assembly 5 after coupling the cooling system 18 to the SoW 14 to the second set of VRMs 38. Figures 4A to 4D illustrate that VRMs with varying heights can be compartmentalized into groups according to height. Different groups can then be used in different SoW assemblies with fasteners of different sizes. Using such compartmentation, the height variation of the VRMs of a particular SoW assembly can be significantly lower than the maximum variation of all VRMs across different SoW assemblies. Although Figures 4A and 4B illustrate SoWs associated with two distinct VRM groups compartmented by height, VRMs can be compartmentalized into any suitable number of groups to reduce height variation within each SoW component. Unless otherwise noted, the components of SoW components 4 and 5 in Figures 4A through 4D may be identical or substantially similar to similar components of any SoW component disclosed herein. SoW components 4 and 5 each may include a heat dissipation structure 12 and a SoW 14 positioned on top of the heat dissipation structure 12. The heat dissipation structure 12 and SoW 14 may be integrated by a TIM 22. SoW component 4 may include a first set of VRMs 36 positioned on top of SoW 14 and a cooling system 18 positioned on top of the first set of VRMs 36. A TIM 20 may be positioned between the first set of VRMs 36 and the cooling system 18. SoW component 5 may include a second set of VRMs 38 positioned on top of SoW 14 and a cooling system 18 positioned on top of the second set of VRMs 38. A TIM 20 may be positioned between the second set of VRMs 38 and the cooling system 18. Based on the height of the VRM, the VRM can be divided into a first group of VRMs 36 and a second group of VRMs 38. The first group of VRMs 36 and the second group of VRMs 38 can be selected from a plurality of VRMs, such that each of the first group of VRMs 36 and the second group of VRMs 38 has a height difference or tolerance smaller than the height difference or tolerance between the plurality of VRMs. In some embodiments, three or more groups of VRMs can be selected from the plurality of VRMs. For example, a third group of VRMs up to the nth group of VRMs can also be selected, where n is an integer of 4 or greater. In some embodiments, the plurality of VRMs may have an average height difference of x, and n groups of VRMs may be selected from the plurality of VRMs. In such embodiments, each of the n groups of VRMs may have an average VRM height difference of less than approximately x / n. For example, when the plurality of VRMs are divided into two groups, the height difference between each group may be less than approximately 1 / 2 of the height difference of the plurality of VRMs. As another example, when the plurality of VRMs are divided into three groups, the height difference between each group may be less than approximately 1 / 3 of the height difference of the plurality of VRMs. As an example, the height of the VRM can vary by approximately 20%. In the case of N VRM groups, the height variation between individual groups of VRMs can be within 20% / N. For example, in the case of 2 VRM groups, each group can have a height variation within approximately 10% of the VRM height. As another example, in the case of 4 VRM groups, each group can have a height variation within approximately 5% of the VRM height. In some embodiments, the height of each of the plurality of VRMs can be measured, and a first number of VRMs from the highest VRM among the plurality of VRMs can be selected as a first group of VRMs 36, and a second number of VRMs 38 from the shortest VRM among the plurality of VRMs can be selected as a second group of VRMs 38. VRM height differences may occur during VRM manufacturing. Each VRM may include a passive portion having a passive component layer and an active portion having two or more active component layers. Both the passive and active portions may have manufacturing tolerances. These manufacturing tolerances may be additive. As shown in Figures 4A and 4B, the height difference between the first group of VRMs 36 and the height difference between the second group of VRMs 38 can be relatively small. The average height difference between the first group of VRMs 36 and the average height difference between the second group of VRMs 38 can be less than the average height difference of the larger group including both the first and second groups of VRMs 36 and 38. In some embodiments, the average height difference between the first group of VRMs 36 and the average height difference between the second group of VRMs 38 can be about half the average height difference between the groups including both the first and second groups of VRMs 36 and 38. In some embodiments, the average height tolerance of the first group of VRMs 36 and the average height tolerance of the second group of VRMs 38 can be within specific values ​​determined at least in part based on the compressive force applied to couple the cooling system 18 to the first and second groups of VRMs 36 and 38. The heat dissipation structure 12, SoW 14, and cooling system 18 can be coupled together via fasteners 40 and 41. In some embodiments, fasteners 40 and 41 may include bolts, such as shoulder bolts. Fasteners 40 and 41 may extend through a portion of the heat dissipation structure 12 and a portion of the cooling system 18. The spacing between the heat dissipation structure 12 and the cooling system 18 in SoW assembly 4 may be greater than the spacing between the heat dissipation structure 12 and the cooling system 18 in SoW assembly 5. Fastener 40 in SoW assembly 4 may be longer than fastener 41 in SoW assembly 5. The longer fastener 40 can accommodate a higher VRM 36. Alternatively, the shorter fastener 41 can accommodate a shorter VRM 38. Various embodiments of the SoW assembly disclosed herein may include height adjustment structures. In some embodiments, the height adjustment structure may be a crown positioned between the cooling system and the SoW (see Figures 5A-5C), a protrusion extending from the cooling system and positioned between the cooling system and the SoW (see Figures 6A and 6B), and at least a portion of a TIM positioned between the cooling system and the SoW and having a thickness different from another TIM (see Figure 8). The height adjustment structure may compensate for the height difference between a first VRM and a second VRM. The crown may be positioned on the first VRM. The total height of the first VRM and the crown is the same as or similar to that of the second VRM (or the total height of the second VRM and another crown on the second VRM). The protrusion may extend from the cooling system and be positioned between the first VRM and the cooling system. The total height of the first VRM and the protrusion may be the same as or similar to that of the second VRM (or the total height of the second VRM and another protrusion). The crown and / or the protrusion may reduce the thickness difference between different TIMs in the SoW assembly. When forces are applied to couple the cooling system and the SoW together, the height adjustment structure allows approximately uniform, equal, or nearly equal compressive forces to be applied to each of the VRMs and each corresponding TIMs in the SoW assembly. In some embodiments, the height adjustment structure allows the TIMs positioned between the VRMs and the cooling system to have the same or similar footprint. In some embodiments, the height adjustment structure can prevent or mitigate excessive increases in the TIM footprint during the coupling process of the SoW 14 and the cooling system 18. Figure 5A shows a schematic cross-sectional side view of the SoW assembly 6 with the height adjustment structure 50 (e.g., crown) before thinning the height adjustment structure 50 according to another embodiment. Figure 5B shows a schematic cross-sectional side view of the SoW assembly 6 after thinning the height adjustment structure 50 and before coupling the cooling system 18 to the VRM 16 on the SoW 14. Figure 5C shows a schematic cross-sectional side view of the SoW assembly 6 after coupling the cooling system 18 to the VRM 36 on the SoW 14. Figures 5A to 5C illustrate features of the embodiment in which the height adjustment structure 50 is added to the VRM 16 to compensate for changes in the VRM height. Unless otherwise noted, the components of the SoW assembly 6 of Figures 5A to 5C may be identical or substantially similar to similar components of any SoW assembly disclosed herein. SoW assembly 6 may include a heat dissipation structure 12 and a SoW 14 positioned above the heat dissipation structure 12. The heat dissipation structure 12 and SoW 14 may have a TIM 22 positioned therebetween. SoW assembly 6 may include a VRM 16 positioned above the SoW 14 and a cooling system 18 positioned above the VRM 16. The VRM 16 and cooling system 18 may have a TIM 20 positioned therebetween. A height adjustment structure 50 may be positioned between the cooling system 18 and the SoW 14. The height adjustment structure 50 can compensate for height differences between the VRMs 16. Using the height adjustment structure 50, a more uniform force can be applied when coupling the cooling system 18 and the SoW 14. By equalizing the compressive forces during manufacturing, the height adjustment structure 50 can reduce the thickness difference between the TIMs 20 between different VRMs 16 and the cooling system 18. In the illustrated embodiment, the height adjustment structure 50 may include first to fifth crowns 50a to 50e respectively positioned on the first to fifth VRMs 16a to 16e of VRM 16. However, the height adjustment structure 50 may be positioned below VRM 16, between TIM 20 and cooling system 18, or at any other suitable location. The height adjustment structure 50 may include a material with relatively high thermal conductivity. For example, in some applications, the height adjustment structure 50 may have the same or substantially similar thermal conductivity as TIM 20. The material of the height adjustment structure 50 may differ from the material of TIM 20. Non-functional structures on the functional circuit elements of VRM 16 may be referred to as crowns, whether the non-functional structure is integrated with or separate from the functional circuit elements. In Figure 5A, the first to fifth crown portions 50a to 50e can be provided on top of the first to fifth VRMs 16a to 16e, which have different heights. Because the first to fifth crown portions 50a to 50e in Figure 5A have the same or approximately similar heights, the total heights of the first crown portion 50a and the first VRM 16a, the second crown portion 50b and the second VRM 16b, the third crown portion 50c and the second VRM 16c, the fourth crown portion 50d and the fourth VRM 16d, and the fifth crown portion 50e and the fifth VRM 16e can be different. In Figure 5B, portions of the first to fifth crown portions 50a to 50e can be removed to make the total heights of the first crown portion 50a and the first VRM 16a, the second crown portion 50b and the second VRM 16b, the third crown portion 50c and the second VRM 16c, the fourth crown portion 50d and the fourth VRM 16d, and the fifth crown portion 50e and the fifth VRM 16e equal or approximately equal to each other. After removing portions of the first to fifth crown portions 50a to 50e, the relative heights of the upper surfaces of the first to fifth crown portions 50a to 50e can be the same or approximately similar. In other words, the height adjustment structure 50 can at least compensate for the VRM height difference to approximately match the spacing of the TIM 20 between the cooling system 18 and the height adjustment structure 50. The height adjustment structure 50 can also take into account the curvature of the SoW 14. Cooling system 18 can be coupled to VRM 36 on SoW 14, as shown in FIG5C. When the heat dissipation structure 12 and cooling system 18 of SoW assembly 6 are brought together to couple with each other, a substantially uniform, equal or nearly equal compressive force can be applied to each of the first to fifth VRMs 16a to 16e, the first to fifth crowns 50a to 50e, and each corresponding TIM 20. Such a substantially uniform, equal or nearly equal compressive force can mitigate the risk of damage to SoW 14 due to coupling cooling system 18 to SoW 14. In some embodiments, the height adjustment structure 50 may be omitted from one or more of the highest VRMs among the first to fifth VRMs 16a to 16e. In some embodiments, the heights of the first to fifth crowns 50a to 50e may be determined at least in part based on the height difference between the heights of the first to fifth VRMs 16a to 16e. For example, the height of the crown positioned above the VRM may be at least the difference between the height of the highest VRM and the height of the VRM. The warpage or curvature of the SoW 14 wafer may also be taken into account when determining the height of the crown. Figure 6A shows a schematic cross-sectional side view of the SoW assembly 7 including the cooling system 18a, before coupling the cooling system 18a to the VRM 16 on the SoW 14, according to an embodiment. Figure 6B shows a schematic cross-sectional side view of the SoW assembly 7 after coupling the cooling system 18a to the first set of VRM 36 on the SoW 14. Figures 6A and 6B illustrate a feature of the embodiment where the height adjustment structure 60 extends from the cooling system 18a to compensate for changes in the height of the VRM 16. Unless otherwise noted, the components of the SoW assembly 7 of Figures 6A and 6B may be identical or substantially similar to similar components of any SoW assembly disclosed herein. SoW assembly 7 may include a heat dissipation structure 12 and a SoW 14 positioned on the heat dissipation structure 12. The heat dissipation structure 12 and SoW 14 may have a TIM 22 positioned therebetween. SoW assembly 7 may include a VRM 16 positioned on the SoW 14 and a cooling system 18a positioned on the VRM 16. The VRM 16 and cooling system 18a may have a TIM 20 positioned therebetween. In some embodiments, as shown in Figures 6A and 6B, the cooling system 18a may include a height adjustment structure 60. In the illustrated embodiment, the height adjustment structure 60 may include first to fifth protrusions 60a to 60e extending from a flat portion 62 of the cooling system 18a. The protrusions 60a to 60e may be referred to as supports. In some other embodiments, the height adjustment structure 60 may be formed separately from the cooling system 18a. In some embodiments, the height adjustment structure 60 may include grooves or recesses formed in the flat portion 62 of the cooling system 18a. In some embodiments, the height adjustment structure 60 may include a combination of one or more protrusions and one or more grooves. In the SoW assembly 7, the VRM 16 can have different heights. During the coupling process for coupling the cooling system 18a to the VRM 16 on the SoW 14, the height adjustment structure 60 of the cooling system 18a can compensate for the VRM height difference, so that the distribution of the compressive force applied to the SoW 14 is more uniform. This can reduce the risk of damage to the SoW 14 during the coupling process. In addition, this can reduce the thickness difference between the TIM 20 between different VRM 16 and the cooling system 18. When the heat dissipation structure 12 and the cooling system 18a of the SoW component 7 are brought together and coupled to each other, a substantially uniform, equal, or nearly equal compressive force can be applied to each of the first to fifth VRMs 16a to 16e, the first to fifth protrusions 60a to 60e, and each corresponding TIM 20. Such a substantially uniform, equal, or nearly equal compressive force can mitigate the risk of damage to the SoW 14. In some embodiments, the protrusions of one or more of the highest VRMs among the first to fifth VRMs 16a to 16e may be omitted. In some embodiments, the heights of the first to fifth protrusions 60a to 60e may be determined at least in part based on the height difference between the heights of the first to fifth VRMs 16a to 16e. In some embodiments, two or more separate height adjustment structures may be provided for the VRMs between the SoW 14 and the cooling systems 18, 18a. For example, a combination of height adjustment structure 60 and height adjustment structure 50 may be included in the SoW assembly. Figure 7A shows a schematic cross-sectional side view of the SoW assembly 8. The SoW assembly 8 includes a wafer 84, first to fourth VRMs 86a to 86d positioned on the wafer 84, a cooling system 88, and first to fourth TIMs 20a to 20d positioned between the first to fourth VRMs 86a to 86d and the cooling system 88. Figure 7A also includes graphs showing the compressive pressure measured between the wafer 84 and the cooling system 88 on the x-axis and the resistance on the y-axis, and graphs showing the force applied to the cooling system 88 on the x-axis and the compressive pressure measured between the wafer 84 and the cooling system 88 on the y-axis. Figure 7B shows a schematic cross-sectional side view of a SoW assembly 7' according to an embodiment. The SoW assembly 7' includes a wafer 84, first to fourth VRMs 86a to 86d positioned on the wafer 84, a cooling system 18a', and first to fourth TIMs 20a to 20d positioned between the first to fourth VRMs 86a to 86d and the cooling system 18a'. The cooling system 18a' may include a height adjustment structure 60'. The height adjustment structure 60' may include first to third protrusions 60a' to 60c' projecting from a flat portion 62' of the cooling system 18'. Unless otherwise indicated, the components of the SoW assembly 7' of Figure 7B may be identical or substantially similar to similar components of any SoW assembly disclosed herein. Figure 7B also includes a graph showing the compressive pressure measured between the wafer 84 and the cooling system 18a' on the x-axis and the resistance on the y-axis, as well as a graph showing the force applied to the cooling system 18a' on the x-axis and the compressive pressure measured between the wafer 84 and the cooling system 18a' on the y-axis. In the SoW assembly 8 illustrated in Figure 7A, the compressive pressure experienced by the third TIM 20c is significantly higher than that experienced by the second TIM 20b. The difference in compressive pressure measured in these two TIMs 20b and 20c is likely due to differences in the spacing between the cooling system 88 and the second VRM 86b, and between the cooling system 88 and the third VRM 86c. In contrast, in the SoW assembly 7', the compressive pressure experienced by the third TIM 20c is approximately similar to that experienced by the second TIM 20b. It can be observed that the second protrusion 60b' helps to make the compressive pressure experienced by the third TIM 20c and the second TIM 20b approximately similar. By utilizing any suitable principles and advantages disclosed herein to make the spacing of the TIMs at each VRM on the wafer the same or approximately similar, the forces applied to the wafer through the VRMs can have less variation and be more uniformly distributed to prevent or mitigate wafer damage. Figure 8 shows a schematic cross-sectional side view of a SoW assembly 9 comprising a cooling system 18 coupled to VRMs 16a to 16e on the SoW 14 via TIM layers 20' of varying sizes. The TIM layers 20' of varying sizes may have different thicknesses to compensate for variations in VRM height. The TIM layers 20' of varying sizes may include first to fifth TIM layers 20'a to 20'e. Unless otherwise indicated, components of the SoW assembly 9 of Figure 8 may be identical or substantially similar to similar components of any other suitable SoW assembly disclosed herein. Different sized TIM layers 20' (first to fifth TIM layers 20'a to 20'e) can be provided on top of the first to fifth VRMs 16a to 16e, which have different heights and act as height adjustment structures. For example, a thinner TIM layer can be provided for a thicker VRM among VRMs 16a to 16e, and a thicker TIM layer can be provided for a thinner VRM among VRMs 16a to 16e. This can adjust the total thickness of the first to fifth VRMs 16a to 16e and the corresponding first to fifth TIM layers 20'a to 20'e to be the same or substantially similar. The thicker TIM portion can be a height adjustment structure to compensate for differences in VRM heights. In some embodiments, one or more of the first to fifth TIM layers 20'a to 20'e can have separate portions. For example, the first TIM layer 20'a can have two or more portions that can be interposed by an intervening layer (not shown). The sum of the thicknesses of the two or more portions can define the thickness of the first TIM layer 20'a. When the heat dissipation structure 12 and the cooling system 18 of the SoW component 9 are brought together to couple with each other, a substantially uniform, equal, or nearly equal compressive force can be applied to each of the first to fifth VRMs 16a to 16e, and to each corresponding layer of the different-sized TIM layers 20'. This substantially uniform, equal, or nearly equal compressive force can mitigate the risk of damage to the SoW 14 due to the coupling of the cooling system 18 to the SoW 14. After the SoW 14 and the cooling system 18 are coupled together, the different-sized TIM layers 20' can have the same or substantially similar density and / or space occupation. Any suitable principles and advantages disclosed herein can be applied to wafer-level packaging and / or high-density multi-die packaging. While the embodiments disclosed herein use a VRM as an example, any suitable electrical module, component, die, chip, etc., can be mounted on a wafer and utilize any suitable principles and advantages disclosed herein. Any suitable combination of features of two or more embodiments disclosed herein can be implemented. For example, a SoW module can have any suitable combination of the selection and mounting features described with respect to FIG3, the compartmenting features described with respect to FIG4A-4D, the height adjustment features described with respect to FIG5A-5C, or the height adjustment features described with respect to FIG6A and 6B. The SoW components disclosed herein can be included in a processing system. Features of the invention (such as any techniques for reducing uneven stress applied to the wafer) can be implemented in any suitable processing system. The processing system can have high computational density and can dissipate the heat generated by the processing system. In some applications, the processing system can perform trillions of operations per second. The processing system can be used and / or specifically configured for high-performance computing and / or compute-intensive applications, such as neural network training and / or processing, machine learning, artificial intelligence, etc. The processing system can implement redundancy. In some applications, the processing system can be used for neural network training to generate data for autonomous driving systems for vehicles (e.g., automobiles), other autonomous vehicle functions, or advanced driver assistance systems (ADAS) functions. Unless the context clearly requires otherwise, throughout this specification and the scope of the claims, the terms “comprising,” “including,” “containing,” “comprise,” “including,” etc., shall be interpreted in an inclusive sense, as opposed to an exclusive or exhaustive sense; that is, in the sense of “including but not limited to.” The term “coupled” as commonly used herein refers to two or more elements that can be directly connected or connected through one or more intermediate elements. Similarly, the term “connected” as commonly used herein refers to two or more elements that can be directly connected or connected through one or more intermediate elements. Additionally, when used in this invention, the terms “in this document,” “above,” “below,” and similar terms shall refer to the entire invention and not to any particular part of the invention. Where the context permits, the use of singular or plural terms in the above detailed description may also include both singular and plural terms, respectively. The term “or” relating to a list of two or more items covers all of the following interpretations: any one of the items in the list, all the items in the list, and any combination of the items in the list. Furthermore, the conditional language used herein (among others, such as "may," "can," "possibly," "may," "for example," "like," etc.), unless otherwise specifically stated or understood in the context in which they are used, is generally intended to convey that certain embodiments include certain features, elements, and / or states, while other embodiments do not include certain features, elements, and / or states. Therefore, such conditional language is generally not intended to imply that features, elements, and / or states are required in any way for one or more embodiments. The foregoing description has been described with reference to specific embodiments. However, the illustrative discussion above is not intended to be exhaustive or to limit the invention to the precise forms described. In view of the above teachings, many modifications and variations are possible. Thus, it is made possible that others skilled in the art can best utilize the described techniques and various embodiments with various modifications suitable for various uses. Although the invention and examples have been described with reference to the drawings, various changes and modifications will become apparent to those skilled in the art. Such changes and modifications are to be understood to be included within the scope of the invention.

[0006] 1,2,3,4,5,6,7,8,9: SoW components h1a, h1b, h2: Height 12: Heat dissipation structure 14:SoW 16,16a-16e:VRM 18,18a': Cooling system 20,20a~20d,20',20'a~20'e:TIM 22:TIM 30: Central Area 32: Edge region 36,38:VRM 40, 41: Fasteners 50, 50a~50e: Height adjustment structure 60, 60a~60e, 60a'~60c': Height adjustment structure 62,62': Flat portion 84: Wafer 86a~86d:VRM 88: Cooling System

Claims

1. A wafer assembly, comprising: Cooling system; wafers; A first electronic module is mounted at a first position on the wafer and coupled to a first part of the cooling system, the first electronic module and the first part of the cooling system being positioned such that a first thermal interface material (TIM) is disposed between the first electronic module and the first part of the cooling system; A second electronic module is mounted on the wafer at a second location different from the first location and coupled to a second part of the cooling system. The second electronic module and the second part of the cooling system are positioned such that a second TIM is disposed between the second electronic module and the second part of the cooling system, wherein the wafer is curved such that the distance between the first location and the cooling system is different from the distance between the second location and the cooling system. And a height adjustment structure disposed between a first position of the wafer and a first portion of the cooling system, the height adjustment structure being configured to compensate for the height difference between the first electronic module and the second electronic module.

2. The wafer assembly as described in claim 1, wherein, The first electronic module is the voltage regulation module (VRM).

3. The wafer assembly as described in claim 1, wherein, The height adjustment structure includes a crown disposed on the first electronic module.

4. The wafer assembly as claimed in claim 1, wherein, The height adjustment structure includes a protrusion extending from the first part of the cooling system.

5. The wafer assembly as claimed in claim 1, further comprising a second height adjustment structure disposed between a second position on the wafer and a second portion of the cooling system, wherein, The height of the second height adjustment structure is different from the height of the first height adjustment structure.

6. The wafer assembly as claimed in claim 1, wherein, The height adjustment structure includes a portion of the first TIM.

7. The wafer assembly as claimed in claim 1, further comprising a heat dissipation structure positioned such that the wafer is located between the cooling system and the heat dissipation structure.

8. A wafer assembly, comprising: A wafer having a central region and an edge region surrounding the central region; A plurality of electronic modules of different heights are mounted on the wafer, such that the average height of a first group of electronic modules located in the central region is greater than the average height of a second group of electronic modules located in the edge region; and a cooling system coupled to the plurality of electronic modules, the cooling system and the plurality of electronic modules being positioned such that a thermal interface material (TIM) is disposed between the cooling system and the plurality of electronic modules, wherein the wafer is curved such that the edge region of the wafer is closer to the cooling system than the central region of the wafer.

9. The wafer assembly as described in claim 8, wherein, The first group of electronic modules has a greater height than the second group of electronic modules.

10. The wafer assembly as claimed in claim 8, further comprising a heat dissipation structure positioned such that the wafer is located between the cooling system and the heat dissipation structure.

11. The wafer assembly as claimed in claim 8, wherein, The multiple electronic modules include multiple voltage regulation modules (VRMs).

12. A method for manufacturing a wafer assembly, the method comprising: Select a first group of electronic modules and a second group of electronic modules from a plurality of electronic modules, such that the height variation of the first group of electronic modules and the height variation of the second group of electronic modules are both less than the height variation of the plurality of electronic modules; mount the first group of electronic modules on a first wafer, and mount the second group of electronic modules on a second wafer; couple a first cooling system and the first group of electronic modules such that a first thermal interface material is located between the first cooling system and the first group of electronic modules; The first set of electronic modules is coupled to a second cooling system and a second set of electronic modules, such that a second thermal interface material is located between the second cooling system and the second set of electronic modules. Mounting the first set of electronic modules on the first wafer includes: mounting a first sub-group of the first set of electronic modules in a central region of the first wafer; and mounting a second sub-group of the first set of electronic modules in an edge region of the first wafer surrounding the central region, wherein the first wafer is curved such that the edge region is spaced from the cooling system at a smaller distance than the central region.

13. The method as described in claim 12, wherein, The multiple electronic modules include multiple voltage regulation modules (VRMs).

14. The method as described in claim 12, wherein, The first wafer includes an integrated circuit die aligned with a corresponding electronic module in the first set of electronic modules.

15. The method as described in claim 12, wherein, The height variation of the first group of electronic modules and the height variation of the second group of electronic modules are each less than half the height variation of the plurality of electronic modules.

16. The method as described in claim 12, wherein, Coupling the first cooling system and the first set of electronic modules includes applying a force to the cooling system to compress the first thermal interface material.

17. The method as described in claim 12, further comprising: A first heat dissipation structure is provided such that the first wafer is located between the first cooling system and the first heat dissipation structure.

18. The method of claim 17, further comprising: The first heat dissipation structure and the first cooling system are secured with the first fastener; And a second fastener is used to secure the second heat dissipation structure and the second cooling system, wherein the second fastener is longer than the first fastener.

19. The method as described in claim 12, further comprising: A third group of electronic modules is selected from the plurality of electronic modules, such that the height change of the third group of electronic modules is less than the height change of the plurality of electronic modules; The third set of electronic modules is mounted on the third wafer; and the third cooling system and the third set of electronic modules are coupled such that the third thermal interface material is located between the third cooling system and the third set of electronic modules.

20. The method as described in claim 12, wherein, The first subgroup of electronic modules has an average height that is greater than the average height of the second subgroup of electronic modules.

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