Electronic package assembly with cooling system and method of forming same

Abstract

The invention provides an electronic packaging assembly and a forming method thereof. The electronic packaging assembly comprises a base packaging substrate, at least one base electronic element and a base mold cover. A support frame attached to the base mold cover, where the support frame has a bottom opening exposing front surfaces of the base mold cover and the base electronic component and an upper opening in fluid communication with the bottom opening; the upper packaging substrate is supported on the supporting frame, the upper electronic component faces the base electronic component, the upper mold cover is contained in the supporting frame, and the height of the upper mold cover is smaller than that of the supporting frame, so that a cooling channel is formed between the upper mold cover and the base mold cover; and wherein the upper package substrate includes an inlet and an outlet formed therethrough.

Description

TECHNICAL FIELD

[0001] The present application relates generally to semiconductor packaging technology, and more particularly, to an electronic package assembly with a cooling system and a method of forming the same. BACKGROUND

[0002] In recent years, the semiconductor industry is constantly facing complex integration challenges as more and more electronic modules are packaged into a single device to achieve multiple functions. When the electronic device is working, multiple electronic modules in the device can generate heat, especially those high-performance logic chips and memory chips, such as central processing units (CPUs), graphics processing units (GPUs), and high-bandwidth memories (HBMs), the heat generation is more serious. In these cases, the generated heat should be dissipated in time to ensure the good function of the electronic modules. Generally, a heat sink can be attached to these electronic modules to facilitate heat dissipation. However, it is noted that the efficiency of the existing heat dissipation method can still be limited, especially for devices including high-performance chips and having a stacked structure.

[0003] Therefore, there is a need for an electronic package assembly with improved heat dissipation capability. SUMMARY

[0004] It is an object of the present application to provide an electronic package assembly with improved heat dissipation capability.

[0005] According to an aspect of the present application, an electronic package assembly is provided. The electronic package assembly includes: a base electronic package including: a base package substrate, at least one base electronic component mounted on the base package substrate, and a base mold cap formed on the base package substrate, the base mold cap encapsulating the at least one base electronic component but exposing a front surface of the at least one base electronic component; a support frame attached on the base mold cap, wherein the support frame has a bottom opening exposing a portion of the base mold cap and the front surface of the at least one base electronic component, the support frame further has an upper opening opposite to and in fluid communication with the bottom opening; an upper electronic package attached on the support frame and including: an upper package substrate supported on the support frame, at least one upper electronic component mounted on the upper package substrate and facing the at least one base electronic component, and an upper mold cap formed on the upper package substrate, the upper mold cap encapsulating the at least one upper electronic component but exposing a front surface of the at least one upper electronic component, wherein the upper mold cap is received within the support frame through the upper opening of the support frame, and a height of the upper mold cap is less than a height of the support frame to form a cooling channel between the upper mold cap and the base mold cap, wherein the cooling channel is configured to receive a coolant fluid and is in direct contact with the exposed electronic components of the at least one base electronic component and the at least one upper electronic component; and wherein the upper package substrate includes an inlet and an outlet through the upper package substrate and aligned with the upper opening, the inlet and the outlet are respectively configured to pump the coolant fluid into the cooling channel and out of the cooling channel.

[0006] According to another aspect of the present application, a method for forming an electronic package assembly is provided. The method includes mounting at least one base electronic component on a base package substrate; forming a base mold cap on the base package substrate to encapsulate the at least one base electronic component, but expose a front surface of the at least one base electronic component; mounting at least one upper electronic component on an upper package substrate; forming an upper mold cap on the upper package substrate to encapsulate the at least one upper electronic component, but expose a front surface of the at least one upper electronic component; attaching a support frame on the front surface of the base mold cap, wherein the support frame has a bottom opening that exposes a portion of the base mold cap and the front surface of the at least one base electronic component, the support frame further has an upper opening that is opposite to and in fluid communication with the bottom opening; attaching the upper package substrate on the support frame, wherein the upper mold cap is received within the support frame through the upper opening of the support frame and faces the base mold cap, and a height of the upper mold cap is less than a height of the support frame to form a cooling channel between the upper mold cap and the base mold cap, wherein the cooling channel is configured to receive a coolant fluid and is in direct contact with the exposed electronic components of the at least one base electronic component and the at least one upper electronic component; and forming an inlet and an outlet through the upper package substrate.

[0007] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the application as claimed. Furthermore, the accompanying drawings which are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description, serve to explain the principles of the application. BRIEF DESCRIPTION OF DRAWINGS

[0008] The drawings referenced herein are incorporated into and constitute a part of this specification. Unless specifically indicated otherwise, features shown in the drawings are representative of some embodiments of the present application, but not all embodiments of the present application, and should not be construed as suggesting to the reader of the specification any other than the representative nature of the features shown.

[0009] Figure 1A An electronic package assembly according to a first embodiment of the present application is shown.

[0010] Figure 1B A top view of a support frame in Figure 1A is shown.

[0011] Figures 2A to 2F Various steps of a method for forming an electronic package assembly according to a second embodiment of the present application are shown.

[0012] Figure 3 An electronic package assembly according to a third embodiment of the present application is shown.

[0013] Figures 4A to 4E Various steps of a method for forming an electronic package assembly according to a fourth embodiment of the present application are shown.

[0014] Throughout the drawings, like reference numerals will be used to refer to like or similar portions throughout the several views. DETAILED DESCRIPTION

[0015] The following detailed description of example embodiments of the application references the accompanying drawings. The drawings illustrate specific example embodiments of the application. The detailed description includes specific details for the purpose of providing a thorough understanding of the present application. Those skilled in the art will understand that the detailed description and the drawings are not intended to constrain the present application to any specific embodiment, and that the present application is capable of other embodiments and is practiced in the spirit and scope of the present application. Accordingly, the reader should not place undue reliance on the description set forth herein.

[0016] In this application, the use of the singular includes the plural, unless specifically stated otherwise. In this application, the use of "or" means "and / or" unless stated otherwise. Furthermore, the use of the term "including" as well as other forms such as "include", "includes" and "included" is not limiting. Also, terms such as "element" or "component" encompass both elements and components comprising a single unit and elements and components that comprise more than one subunit unless specifically stated otherwise. Further, the section headings used herein are for organizational purposes only and are not meant to be used as limiting the subject matter described.

[0017] As used herein, spatial or directional terms, such as "below," "above," "left," "right," "vertical," "horizontal," "side" and the like, can be used for ease of describing the illustrated embodiments. It will be understood, however, that the spatial and directional terms should be interpreted in light of the orientation of the apparatus as shown in the figures. The apparatus can be oriented in other ways (rotated at 90 degrees, or in other orientations), and the spatially relative terms used herein can be interpreted accordingly. It will be understood that when an element is referred to as being "connected to" or "coupled to" another element, it can be directly connected to or coupled to the other element, or intervening elements can be present.

[0018] As mentioned above, for a device that encapsulates multiple electronic modules, the electronic modules can generate significant heat during operation of the device, especially for those high performance logic chips and memory chips, such as central processing units (CPUs), graphics processing units (GPUs), and high bandwidth memory (HBM), the heat generation is even more severe. In these cases, the generated heat should be promptly dissipated to ensure good functionality of the electronic modules.

[0019] To address the heat dissipation issue, a new electronic package assembly with a cooling system is provided. The electronic package assembly includes a base electronic package, an upper electronic package, and a support frame attached between the upper electronic package and the base electronic package. The support frame can form a cooling channel between the upper electronic package and the base electronic package, such that a coolant fluid can flow therethrough and directly contact the upper electronic package and the base electronic package. Since the coolant fluid is in direct contact with the electronic packages, the coolant fluid can effectively dissipate the heat generated within the device. It can be appreciated that the electronic package assembly can be used in a device with a multi-layer structure and stacked with high performance electronic modules, which requires better heat dissipation capability.

[0020] Figure 1A An electronic package assembly according to a first embodiment of the present application is shown.

[0021] As Figure 1A shown, the electronic package assembly has a double-layer stacked structure, i.e., a lower base electronic package and an upper upper electronic package. The base electronic package includes a base package substrate 100 with embedded interconnect lines. The base package substrate 100 has a front surface and a back surface, which are opposite to each other. The front surface of the base package substrate 100 can serve as a platform on which electronic components and conductive devices can be mounted. In some embodiments, the electronic package assembly can be a double-sided molded (DSM) package, thus the back surface can also serve as another platform on which electronic components can be mounted. A plurality of sets of conductive pads (not shown) can be formed on the front surface and / or the back surface of the base package substrate 100 for mounting electronic components. It can be appreciated that the plurality of sets of conductive pads can be exposed portions of the interconnect lines formed within the base package substrate 100.

[0022] The base electronic package includes at least one base electronic component 101 mounted on a front surface of a base package substrate 100 via solder bumps. In some embodiments, the at least one base electronic component 101 can have a conductive pad on its back surface for mounting the base electronic component 101 onto the base package substrate 100. The base electronic component 101 can include high performance chips such as central processing units (CPUs), graphics processing units (GPUs), and high bandwidth memories (HBMs), which can have high power consumption and generate a large amount of heat when in operation. In addition, a base mold cap 102 is formed on the base package substrate 100 to encapsulate the at least one base electronic component 101. As shown in Figure 1A , the base mold cap 102 encapsulates the side surfaces of the at least one base electronic component 101, but exposes the front surface of the at least one base electronic component 101. Here, the front surface of the base electronic component 101 is the surface that is away from the base package substrate 100 and the solder bumps. In some embodiments, more than one base electronic component 101 is mounted on the base package substrate 100, and the front surfaces of all the base electronic components 101 are substantially in the same horizontal plane. In addition, the base electronic package can include at least one additional base electronic component. The additional base electronic component can be a passive electronic component such as a resistor or a capacitor, or other smaller electronic components. In some embodiments, the additional base electronic component can have a smaller height compared to the height of the base electronic component 101. That is, the base mold cap 102 can encapsulate the side surfaces and the front surface of the at least one additional base electronic component.

[0023] As shown in Figure 1A , similar to the base electronic package, the upper electronic package includes an upper package substrate 110, at least one upper electronic component 111 mounted on the upper package substrate 110 via solder bumps, and an upper mold cap 112 formed on the upper package substrate 110, which encapsulates the at least one upper electronic component 111 but exposes the front surface of the at least one upper electronic component 111. Details of the upper electronic package can be referred to those shown with respect to the base electronic package, which will not be elaborated here for simplicity.

[0024] Still referring to Figure 1A , the electronic package assembly further includes a support frame 120 attached between the base electronic package and the upper electronic package. Figure 1B is Figure 1A a top view of the support frame 120 shown in Figure 1A , the support frame 120 shown in Figure 1B is a cross-sectional view of the support frame 120 along line AA' of

[0025] As shown in Figure 1A and1B As shown in , the support frame 120 is attached to the front surface of the base mold cover 102 for supporting and positioning the upper electronic package. In some embodiments, the support frame 120 may include liquid crystal polymer or stainless steel, or other similar materials with sufficient strength. In some embodiments, the support frame 120 has a rectangular ring shape, which includes four long plates connected to each other, and which is attached to the edge area of ​​the base mold cover 102. In some other embodiments, the support frame 120 may have different shapes, such as a circular ring, a hexagonal ring or an octagonal ring, as long as the support frame can be attached to the base mold cover and accommodate the upper electronic package. In a preferred embodiment, the shape layout of the support frame can be coordinated with the shape layout of the base mold cover and the shape layout of the upper mold cover. Still referring to Figure 1A The support frame 120 has a bottom opening and an upper opening opposite the bottom opening. The upper opening is in fluid communication with the bottom opening, thereby forming a vertical channel between the front and back surfaces of the support frame 120. In particular, the bottom opening exposes at least a portion of the front surface of the base mold cover 102 and the front surface of the at least one base electronic component 101.

[0026] The upper electronic package can be turned over and then mounted on the support frame 120, whereby the upper electronic component 111 can face the base electronic package. In particular, the front surface of the upper package substrate 110 can be supported on the support frame 120 at the edge region. The symmetrical shape layout of the support frame 120 can provide a balanced supporting force for the upper package substrate 110. In addition, the upper mold cover 112 and the upper electronic component 111 can be accommodated in the vertical channel of the support frame 120 through the upper opening of the support frame 120. The front surface of the upper mold cover 112 and the front surface of the at least one upper electronic component 111 can face the front surface of the base mold cover 102 and the front surface of the at least one base electronic component 101. In addition, the height of the upper mold cover 112 is less than the height of the support frame 120. Because the support frame 120 and the upper mold cover 112 are attached to the same front surface of the upper package substrate 110, the height difference between the support frame 120 and the upper mold cover 112 enables a cooling channel 130 to be formed between the upper mold cover 112 and the base mold cover 102, which can be used to accommodate a coolant fluid flowing therein and remove heat generated by the base electronic component 101 and the upper electronic component 111. In addition, the size of the upper mold cover 112 is smaller than that of the base mold cover 102, so that the cooling channel 130 can extend upward into the upper package substrate 110. The upper package substrate 110 further includes an inlet 141 and an outlet 142 that pass through the upper package substrate 110 and are aligned with the upper opening of the support frame 120. Figure 1BAs shown, the support frame 120 further includes a pair of slots 144, 145 opposite to each other and disposed at the inner walls of the support frame 120. The pair of slots 144, 145 can be formed through the support frame 120 and extend vertically between the front surface and the back surface of the support frame 120. The slots 144, 145 are vertically aligned with the inlet 141 and the outlet 142, respectively, such that the coolant fluid can flow into and out of the cooling channel 130. In some other embodiments, the pair of slots 144, 145 can also be formed within the middle regions of the respective long plates of the support frame 120 and can be disposed proximate to the electronic components.

[0027] In addition, the coolant fluid in the cooling channel 130 can be circulated and cooled by a pump 144 and a heat sink 145 connected to the pump 144. In the illustrated embodiment, the pump 144 can be a centrifugal pump, which can be connected to the two pipes 140a, 140b and the heat sink 145. The pump 144 can be configured to pump the coolant fluid into one of the pipes 140a and out of the other pipe 140b, thereby causing the coolant fluid to circulate within the pipes 140a, 140b and the cooling channel 130. Figure 1A In the illustrated embodiment, the two pipes 140a, 140b can be connected to the cooling channel 130, with one pipe 140a as an inlet pipe to introduce the coolant fluid into the cooling channel 130 and the other pipe 140b as an outlet pipe to discharge the coolant fluid out of the cooling channel 130. The pipes 140a, 140b can comprise materials such as polyvinyl chloride (PVC), polyurethane (PU), metal, etc. In particular, the cooling channel 130 can be connected to one end of each of the two pipes 140a, 140b through the inlet 141 and the outlet 142, respectively. The other end of each of the two pipes 140a, 140b can be connected to the pump 144, which pumps the coolant fluid into one of the pipes 140a and out of the other pipe 140b, thereby causing the coolant fluid to circulate within the pipes 140a, 140b and the cooling channel 130. The heat sink 145 can be connected to the pump 144 to cool the coolant fluid as it enters the pump 144. In some other embodiments, the heat sink 145 can be coupled in one of the pipes 140a, 140b to dissipate heat from the coolant fluid flowing therein.

[0028] When an electronic package equipped with such a cooling system operates, the base electronic components 101 and upper electronic components 111 may generate heat. This generated heat gradually accumulates within the base mold cover 102 and upper mold cover 112. Pump 144 can be activated to pump coolant fluid into pipe 140a. The coolant fluid then flows through pipe 140a and inlet 141 into cooling channel 130. After direct heat exchange between the coolant fluid and the electronic components, it removes the heat generated within the electronic package. The heated coolant fluid then flows out of cooling channel 130 through outlet 142 into pipe 140b, returning to pump 144, completing the coolant fluid cycle. Furthermore, during this process, radiator 145 can be activated to cool the coolant fluid to a lower temperature, making it suitable for a new cooling cycle. It will be appreciated that radiator 145 can be either an active or passive radiator. In addition, the electronic package assembly may include valves 143, each valve being disposed at the inlet 141 and the outlet 142 in the corresponding pipes 140a, 140b to adjust the flow rate of the coolant fluid in the cooling channel 130. When the device is operated at high power, that is, when more heat may be generated during device operation, the valve 143 may be adjusted to increase the flow rate of the coolant fluid.

[0029] like Figure 1A As shown, the base mold cover 102 and the upper mold cover 112 completely encapsulate the main body of the base electronic component 101 and the upper electronic component 111, and only expose the front surfaces of the base electronic component 101 and the upper electronic component 111. More specifically, the base mold cover 102 and the upper mold cover 112 can encapsulate the side surfaces of the base electronic component 101 and the upper electronic component 111, the bottom surfaces of the base electronic component 101 and the upper electronic component 111, and the electrical connections between the base package substrate 100, the upper package substrate 110 and the corresponding electronic components 101 and 111, such as conductive pads and solder bumps. In addition, the conductive elements within the electronic components 101 and 111 can also be completely encapsulated during their pre-packaging process. For example, the pre-packaging process allows the front surfaces of the electronic components 101 and 111 to serve as sealing surfaces (e.g., silicon oxide surfaces, undoped silicon surfaces, or other similar non-conductive surfaces) without any exposure of the conductive elements at the front surfaces. Therefore, even if the coolant fluid can directly contact the front surfaces of the mold covers 102, 112 and the electronic components 101, 111, potential leakage or short circuit failures can be avoided, thereby achieving good electrical reliability and safety of the electronic package assembly. In addition, in some embodiments, the coolant fluid includes a deionized coolant fluid (e.g., deionized water). When the coolant fluid flows through the cooling channel 130, it is electrically insulated from the base electronic component 101 and the upper electronic component 111, thereby improving the reliability of the electronic package assembly.

[0030] An electronic package assembly with such a cooling system can have the following advantages. First, because the upper electronic package, cooling channel, and base electronic package form a sandwich structure with the cooling channel formed therein, the coolant fluid in the cooling channel can simultaneously directly contact the exposed front surfaces of the at least one base electronic component, the base mold cover, the at least one upper electronic component, and the upper mold cover, thereby dissipating heat more efficiently. Second, the cooling channel within the electronic package assembly is defined by the corresponding surfaces of the upper mold cover, the base mold cover, and the support frame, which creates a compact packaging structure without requiring additional space for cooling pipes or heat sinks. Third, no additional process steps, such as etching or grooving, are required to form the cooling channel within the electronic package assembly, which reduces the production cost of the device. In some embodiments, once the coolant fluid enters the cooling channel, it can be spread over nearly the entire front surfaces of the base mold cover and the upper mold cover, thereby creating a relatively large cooling contact surface and more effectively cooling the electronic package assembly.

[0031] like Figure 1A and 1B As shown in FIG, a pair of inlet 141 and outlet 142 in the upper package substrate 110 vertically extends through the support frame 120 and is connected to the cooling channel 130 via the pair of grooves 144 and 145. In some other embodiments, more than one pair of inlet 141 and outlet 142 and more than one pair of grooves 144 and 145 are formed in the upper package substrate 110 and the support frame 120, respectively. More specifically, multiple pairs of grooves surrounding the support frame 120 may be arranged, for example, Figure 1B In the illustrated embodiment, multiple pairs of grooves surrounding the support frame 120 can be arranged at the four long plates of the rectangular ring. This allows for more inlets and outlets to be formed through the upper package substrate, vertically aligned with corresponding grooves in the support frame 120. Furthermore, more pipes or pipe branches can be provided and connected to these inlets and outlets. This allows for a more even distribution of coolant fluid into the cooling channels 130 and allows the coolant fluid to flow over a larger area of ​​the mold covers 102, 112 and electronic components 101, 111, enabling uniform cooling of the electronic package assembly.

[0032] In some other embodiments, a support grid and a support frame can be formed within the cooling channel 130 to support the upper electronic package on the base electronic package. In some embodiments, the support grid is connected to the support frame 120 as a single piece, i.e., the support grid is integrally formed with the support frame 120. More specifically, the support grid can be a plurality of parallel vertical posts attached between the base mold cover 102 and the upper mold cover 112. The vertical posts can be spaced apart from each other to allow the coolant fluid to flow within the cooling channel 130, while the vertical posts can also be connected to the support frame 120 with horizontal links to form a single piece. The vertical posts and the horizontal links expose a substantial portion of the front surfaces of the upper electronic components 111 and the base electronic components 101 to allow heat exchange between the electronic components and the coolant fluid. In some alternative embodiments, the base mold cover 102 can have raised molding blocks on the front surface thereof, which can be formed in the same molding process as the base mold cover 102. After the upper electronic package is attached to the support frame 120, the raised molding blocks can provide mechanical support for the upper mold cover 112. In particular, the raised molding blocks can also not cover the front surface of the base electronic components 101, but cover the front surface of additional base electronic components 101 that generate less heat than the base electronic components 101. It can be appreciated that the raised molding blocks can additionally or alternatively be formed on the front surface of the upper mold cover 112.

[0033] In Figure 1A and 1B In the embodiment shown, the inlet 141 and the outlet 142 are disposed around the upper mold cover 112. In some other embodiments, at least one additional inlet or outlet can be formed through the upper mold cover 112 and the upper package substrate 110, which can be disposed in the central region of the upper mold cover 112 and the upper package substrate 110. Thus, the coolant fluid can also pass through the interior of the upper mold cover 112, thereby increasing the cooling surface that the upper electronic components 111 and the upper mold cover 112 can contact.

[0034] In addition, as Figure 1AAs shown, the electronic package assembly can further include at least one conductive element 150 formed between the base package substrate 100 and the upper package substrate 110. In this embodiment, the at least one conductive element 150 can be disposed around the support frame 120. More specifically, at least a portion of the base package substrate 100, such as an edge region located around the base mold cap 102, can be exposed for mounting of external electronic modules. Similarly, at least a portion of the upper package substrate 110 can also be exposed for mounting of the support frame 120 and external electronic modules. The at least one conductive element 150 can be attached between the exposed portion of the base package substrate 100 and the exposed portion of the upper package substrate 110, thereby forming an electrical connection between the base package substrate 100 and the upper package substrate 110. In this manner, the upper electronic package and the base electronic package can be interconnected to form an integrated circuit system. In some embodiments, the conductive element can include a conductive post, e-bar block, or a bonded wire. Additionally, a plurality of additional solder bumps 160 can be formed on the back surface of the base package substrate 100 for mounting the electronic package assembly onto an external electronic module.

[0035] It will be appreciated that although Figure 1A While a two-tier structure is depicted with the upper electronic package stacked on the lower base electronic package, the number of electronic packages stacked together can not be limited to two, and in some examples, more than two tiers of packages can be integrated together. Accordingly, additional support frames can also be introduced to form additional cooling channels between adjacent electronic packages in the stack.

[0036] Figures 2A to 2F Various steps of a method for forming an electronic package assembly according to a second embodiment of the present application are shown. The electronic package assembly can be similar to the electronic package assembly shown in Figure 1A and 1B .

[0037] As Figure 2AAs shown, a base packaging substrate 200 having embedded interconnects 203 is provided. At least one base electronic component 201 is mounted on the front surface of the base packaging substrate 200 via solder bumps. Next, a base molding material is formed on the base packaging substrate 200 to encapsulate the at least one base electronic component 201. The base molding material is formed using a molding process such as an injection molding process, which covers the corresponding front surface of the base electronic component 201 for encapsulation. The base molding material includes epoxy resin, polyester resin, etc. In some embodiments, the base molding material can be formed using various other molding techniques, including transfer molding, compression molding, or film assisted molding (FAM). In some embodiments, the base molding material can be selectively formed on the central area of ​​the base packaging substrate 200, while the edge area of ​​the base packaging substrate 200 is exposed for mounting external electronic components. Next, a grinding process can be performed on the front surface of the base molding material to expose the front surface of the at least one base electronic component 201, thereby forming a base mold cover 202, wherein its front surface is flush with the front surface of the base electronic component 201. In this way, a base electronic package can be formed.

[0038] Next, if Figure 2B As shown, a support frame 220 is attached to the front surface of the substrate mold cover 202. The support frame 220 has a bottom opening that exposes a portion of the substrate mold cover 202 and the front surface of the at least one substrate electronic component 201. The support frame 220 further includes an upper opening opposite the bottom opening and in fluid communication with the bottom opening. The fluidly interconnected bottom opening and upper opening together form a vertical channel extending vertically through the support frame 220. In some embodiments, the support frame 220 further includes an adhesive material 221 located on its back and front surfaces, which enables the support frame 220 to be securely attached between the substrate mold cover 202 and a subsequently attached upper electronic package. In some embodiments, the support frame 220 also includes a pair of grooves opposing each other on the inner wall of the support frame 220, which are formed through the support frame 220.

[0039] Next, if Figure 2C As shown, an upper package substrate 210 having embedded interconnect lines 213 is provided. At least one upper electronic component 211 is formed on a central region of the upper package substrate 210. Next, a pair of grooves 241, 242 are formed through the upper package substrate 210 and surrounding the at least one upper electronic component 211, while the majority of the upper package substrate 210 remains interconnected as a single piece. The pair of grooves 241, 242 serve as the inlet 241 and outlet 242 of the cooling channel that will be formed later. It will be appreciated that the position and layout of the pair of grooves 241, 242 can be coordinated with the position and layout of the grooves within the support frame 220.

[0040] Next, an upper mold cover 212 is formed on the central area of ​​the upper package substrate 210 to encapsulate the at least one upper electronic component 211 but expose the grooves 241, 242 and the edge area of ​​the upper package substrate 210. The upper mold cover 212 further exposes the front surface of the at least one upper electronic component 211. More specifically, the upper mold cover 212 is formed by forming an upper molding material on the upper package substrate 210 to encapsulate the at least one upper electronic component 211, and then grinding the top portion of the upper molding material until the front surface of the at least one upper electronic component 211 is exposed to form the upper mold cover 212. The formation of the upper mold cover 212 can be similar to the formation process of the base mold cover 202. In this way, the upper electronic package is formed.

[0041] In some other embodiments, the upper electronic package can be formed before the base electronic package is formed. It is also understood that the upper electronic package and the base electronic package can be formed simultaneously.

[0042] Next, if Figure 2D As shown, at least one conductive element 250 is formed on the exposed front surface of the upper package substrate 210. The conductive element may include at least one conductive pillar with conductive pads formed on its front and back surfaces. The conductive pillar may include a metal material such as Cu or Al.

[0043] Next, if Figure 2E As shown, the upper electronic package can be flipped over, and then the upper package substrate 210 can be attached to the support frame 220, wherein the edge area of ​​the front surface of the upper package substrate 210 can be attached to the surface of the support frame 220. The upper mold cover 212 is received within the support frame 220 through the upper opening of the support frame 220 and faces the base mold cover 202. The height of the upper mold cover 212 is less than the height of the support frame 220, thereby forming a cooling channel 230 between the upper mold cover 212 and the base mold cover 202 after the upper electronic package is attached to the support frame 220. During the attachment process, a pair of grooves formed in the support frame 220 and a pair of grooves formed in the upper package substrate 210 (i.e., the inlet 241 and the outlet 242) can be vertically aligned with each other, respectively, and they are connected to the cooling channel 230 for fluid communication with the external pipeline. In some embodiments, solder paste and / or flux material may be impregnated onto the front surface of the conductive pillars 250 before attaching the upper package substrate 210 to the support frame 220. In this manner, during the attachment step, the conductive pillars 250 may also be mounted on the front surface of the base package substrate 200 to electrically connect the upper package substrate 210 with the base package substrate 200. Next, additional solder bumps 260 may be formed on the back surface of the base package substrate 200.

[0044] Next, if Figure 2F As shown, pipes 240a, 240b can be fluidly connected to the cooling channel 230 via an inlet 241 and an outlet 242. A pump 244 can be connected to the pipes 240a, 240b to circulate coolant fluid within the pipes 240a, 240b and the cooling channel 230 (which can be filled later), and a heat sink 245 can also be connected to the pump 244 to cool the coolant fluid, thereby forming a cooling system within the electronic package assembly.

[0045] More details of the above components can be similar to Figure 1A and 1B For the sake of simplicity, the components of the illustrated electronic package will not be described in detail here.

[0046] Figure 3 The electronic packaging assembly according to the third embodiment of the present application is shown. Figures 2A to 2F The electronic packaging components shown have similar structures and formation processes, but Figure 3 The conductive element 350 in the electronic package assembly is an e-bar block 350 instead of Figure 2F The conductive pillars 250 are shown. More specifically, the e-bar block 350 may include built-in conductive pillars (e.g., copper pillars) and an insulating base material that separates the conductive pillars from each other. In some embodiments, two e-bar blocks 350 may be mounted between the upper package substrate 210 and the base package substrate 200 via solder bumps, for example, on both sides of the support frame 220.

[0047] Figures 4A to 4E Various steps of a method for forming an electronic package assembly according to a fourth embodiment of the present application are shown.

[0048] like Figure 4A As shown, a base package substrate 400 having embedded interconnects is provided. At least one base electronic component 401 is mounted on the front surface of the base package substrate 400 via solder bumps. Next, a base mold cover 402 is formed on the base package substrate 400 to encapsulate the at least one base electronic component 401 but expose the front surface of the at least one base electronic component 401, thereby forming a base electronic package. Next, a support frame 420 is attached to the front surface of the base mold cover 402.

[0049] like Figure 4B As shown, an upper package substrate 410 having embedded interconnects is provided. At least one upper electronic component 411 is mounted on the central region of the upper package substrate 410. Next, an upper mold cap 412 is formed on the central region of the upper package substrate 410 to encapsulate the at least one upper electronic component 411 but expose the front surface of the at least one upper electronic component 411, thereby forming an upper electronic package.

[0050] Next, if Figure 4C As shown, the upper electronic package can be flipped over and the upper package substrate 410 attached to the support frame 420. The upper mold cover 412 is received within the support frame 420 through the upper opening of the support frame and faces the base mold cover 402. The height of the upper mold cover 412 is less than that of the support frame 420, thereby forming a cooling channel 430 between the upper mold cover 412 and the base mold cover 402 after the upper electronic package is attached to the support frame 420. Next, at least one bonding wire 450 is formed between the upper package substrate 410 and the base package substrate 400 to electrically connect the upper package substrate 410 to the base package substrate 400. In some embodiments, four or more bonding wires 450 can be formed at the four corners of the base package substrate 400 and the four corresponding corners of the upper package substrate 410. Each bonding wire 450 can include a flexible conductive material, such as Cu or Al, which may or may not be coated with a polymer layer. The bonding wires 450 may provide greater flexibility in the layout design of the electrical connections between the upper electronic package and the base electronic package.Next, additional solder bumps 470 may be formed on the back surface of the base package substrate 400.

[0051] Next, if Figure 4D As shown, an additional mold layer 460 is formed on the base package substrate 400 to encapsulate the base electronic package, the support frame 420, the upper electronic package, and the at least one bonding wire 450. More specifically, the back surface of the upper package substrate 410 is also encapsulated by the additional mold layer 460. Because the cooling channel 430 is sealed within the base package and the upper package, no molding material can flow into the cooling channel 430 through any openings.

[0052] Next, if Figure 4E As shown, a portion of the upper package substrate 410 surrounding the upper mold cover 412 and a portion of the additional mold layer 460 on the upper package substrate 410 are removed to form an inlet 441 and an outlet 442 extending through the upper package substrate 410 and partially through the additional mold layer 460. These inlet 441 and outlet 442 are fluidically connected to the cooling channel 430 and fluidically connect the cooling channel to the external space. The inlet 441 and outlet 442 can be formed through an etching process or a trenching process, and this process can be controlled to stop when the cooling channel 430 is exposed. In this way, the cooling channel 430 can be further connected to an external pipeline via the inlet 441 and outlet 442 to form a circulating cooling system within the electronic package assembly in a subsequent step. In addition, dust or residue left during the formation of the inlet 441 and outlet 442 can be removed by the coolant fluid flowing through the cooling channel 430.

[0053] Although the exemplary electronic package assembly and method for forming the electronic package assembly of the present application are described in conjunction with the corresponding figures, those skilled in the art will appreciate that modifications and adaptations may be made to the electronic package assembly and method for forming the electronic package assembly without departing from the scope of the present invention.

[0054] Various embodiments have been described herein with reference to the accompanying drawings. However, it will be apparent that various modifications and variations may be made thereto, and that additional embodiments may be implemented without departing from the broader scope of the invention as set forth in the appended claims. Furthermore, other embodiments will be apparent to those skilled in the art from consideration of the specification and practice of one or more embodiments of the invention disclosed herein. It is therefore intended that this application and the examples herein be considered merely exemplary, with the true scope and spirit of the invention being indicated by the list of the appended exemplary claims.

Claims

1. An electronic package assembly, comprising: Comprising: a base electronic package comprising: a base package substrate, at least one base electronic component mounted on the base package substrate, and a base mold cap formed on the base package substrate, the base mold cap encapsulating the at least one base electronic component but exposing a front surface of the at least one base electronic component; a support frame attached on the base mold cap, wherein the support frame has a bottom opening exposing a portion of the base mold cap and the front surface of the at least one base electronic component, the support frame further has an upper opening opposite to and in fluid communication with the bottom opening; an upper electronic package attached on the support frame and comprising: an upper package substrate supported on the support frame, at least one upper electronic component mounted on the upper package substrate and facing the at least one base electronic component, and an upper mold cap formed on the upper package substrate, the upper mold cap encapsulating the at least one upper electronic component but exposing a front surface of the at least one upper electronic component, wherein the upper mold cap is contained within the support frame through the upper opening of the support frame, and a height of the upper mold cap is less than a height of the support frame to form a cooling channel between the upper mold cap and the base mold cap, wherein the cooling channel is for containing a coolant fluid and is in direct contact with the exposed electronic components of the at least one base electronic component and the at least one upper electronic component; and wherein the upper package substrate comprises an inlet and an outlet through the upper package substrate and aligned with the upper opening, the inlet and the outlet are respectively for pumping the coolant fluid into the cooling channel and out of the cooling channel.

2. The electronic package assembly of claim 1, wherein, Further comprising: a pipe fluidly connected with the cooling channel via the inlet and the outlet; a pump connected to the pipe to circulate the coolant fluid within the pipe and the cooling channel; and a heat sink connected to the pump to cool the coolant fluid. Further comprising one or more valves disposed within the pipe to regulate a flow rate of the coolant fluid within the cooling channel.

3. The electronic package assembly of claim 2, wherein, Further comprising at least one electrically conductive element formed between the base package substrate and the upper package substrate to electrically connect the base package substrate with the upper package substrate, wherein the at least one electrically conductive element is disposed around the support frame.

4. The electronic package assembly of claim 1, wherein, The electrically conductive element comprises an electrically conductive post.

5. The electronic package assembly of claim 4, wherein, The electrically conductive element comprises a bond wire.

6. The electronic package assembly of claim 4, wherein, The electrically conductive element comprises an e-bar block.

7. The electronic package assembly of claim 4, wherein, The base electronic component comprises a CPU, a GPU, or a memory chip.

8. The electronic package assembly of claim 1, wherein, The coolant fluid comprises a deionized coolant fluid.

9. The electronic package assembly of claim 1, wherein, The support frame further comprises an adhesive material between the support frame and the base mold cap or between the support frame and the upper package substrate.

10. The electronic package assembly of claim 1, wherein, ​ 11. The electronic package assembly of claim 1, wherein, Further comprising a support grid formed within the cooling channel and interconnected with the support frame as a single piece, wherein the support grid is configured to support the upper electronic package on the base electronic package without obstructing the flow of the coolant fluid within the cooling channel.

12. A method for forming an electronic package assembly, comprising: The method comprises: mounting at least one base electronic component on a base package substrate; forming a base mold cap on the base package substrate to encapsulate the at least one base electronic component, but expose a front surface of the at least one base electronic component; mounting at least one upper electronic component on an upper package substrate; forming an upper mold cap on the upper package substrate to encapsulate the at least one upper electronic component, but expose a front surface of the at least one upper electronic component; attaching a support frame on the front surface of the base mold cap, wherein the support frame has a bottom opening that exposes a portion of the base mold cap and the front surface of the at least one base electronic component, the support frame further has an upper opening that is opposite to and in fluid communication with the bottom opening; attaching the upper package substrate on the support frame, wherein the upper mold cap is received within the support frame through the upper opening of the support frame, faces the base mold cap, and a height of the upper mold cap is less than a height of the support frame to form a cooling channel between the upper mold cap and the base mold cap, wherein the cooling channel is for receiving a coolant fluid and is in direct contact with the exposed electronic components of the at least one base electronic component and the at least one upper electronic component; and forming an inlet and an outlet through the upper package substrate.

13. The method according to claim 12, characterized in that Before attaching the upper package substrate on the support frame, the method further comprises: forming at least one conductive element on the upper package substrate, wherein the at least one conductive element and the upper mold cap are on a same side of the upper package substrate; and attaching the upper package substrate on the support frame further comprises mounting the at least one conductive element on the base package substrate to electrically connect the upper package substrate with the base package substrate.

14. The method of claim 13, wherein, The conductive element comprises a conductive pillar or an e-bar block.

15. The method of claim 13, wherein, The inlet and the outlet through the upper package substrate are formed before attaching the upper package substrate on the support frame.

16. The method of claim 12, wherein, After attaching the upper package substrate on the support frame, the method further comprises: forming at least one bonding wire between the upper package substrate and the base package substrate to electrically connect the upper package substrate with the base package substrate; and forming an additional molding layer on the base package substrate to encapsulate the base package substrate, the base mold cap, the support frame, the upper package substrate, and the at least one bonding wire.

17. The method of claim 16, wherein, The inlet and the outlet through the upper package substrate are formed after forming the additional molding layer on the base package substrate.

18. The method of claim 12, wherein, The step of forming a base mold cap includes: forming a base molding material on the base package substrate to encapsulate the at least one base electronic component; and grinding a front surface of the base molding material to expose a front surface of the at least one base electronic component, thereby forming the base mold cap; and the step of forming an upper mold cap includes: forming an upper molding material on the upper package substrate to encapsulate the at least one upper electronic component; and grinding a front surface of the upper molding material to expose a front surface of the at least one upper electronic component, thereby forming the upper mold cap.

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