CN114650655A

CN114650655A - Interconnection and heat dissipation structure of wafer prefabricated part and PCB and manufacturing method thereof

Info

Publication number: CN114650655A
Application number: CN202210559461.7A
Authority: CN
Inventors: 邓庆文; 张坤; 李顺斌; 张汝云
Original assignee: Zhejiang Lab
Current assignee: Zhejiang Lab
Priority date: 2022-05-23
Filing date: 2022-05-23
Publication date: 2022-06-21
Anticipated expiration: 2042-05-23
Also published as: CN114650655B

Abstract

The invention discloses an interconnection and heat dissipation structure of a wafer prefabricated part and a PCB (printed Circuit Board) and a manufacturing method thereof. The invention solves the problems of interconnection and heat dissipation of the large-size wafer prefabricated part and the warped PCB, thereby providing technical support for power supply of the high-power wafer and rapid and stable information exchange between the wafer and the PCB.

Description

Interconnection and heat dissipation structure of wafer prefabricated part and PCB and manufacturing method thereof

Technical Field

The invention relates to the technical field of micro-nano processing, in particular to an interconnection and heat dissipation structure of a wafer prefabricated part and a PCB (printed circuit board) and a manufacturing method thereof.

Background

Along with the gradual failure of Moore's law and Dender's scaling law, the improvement of the computing performance by the process progress is obviously slowed down, the data volume of the interconnection of everything is exponentially and explosively increased, the 'scissors difference' gap between the data scale and the computing power is larger and larger, and the integrated circuit is coming to the important revolution of the technology and the industry of the 'post Moore' era.

Aiming at the problem that moore's law is inexorable, the academic and industrial circles mainly adopt a chip-level integration (SOC) technology, a system-in-package (SIP) technology and a wafer-level System (SOW) technology to expand the moore's law. The SOC technology is still a chip design technology essentially, chips with different functions and the same process are integrated together, and the SOC is difficult to form an independent system with powerful functions due to the chip processing technology and the performance of semiconductor materials; the high-density substrate is an SIP integrated physical carrier, the functions of the high-density substrate comprise electrical interconnection among components, transmission of signals such as radio frequency, analog and digital signals, and the high-density substrate can be embedded with partial passive elements, power dividers, filters and the like to provide heat dissipation channels for the components. The SIP packaging technology essentially adopts a flip chip process or a wire bonding process to perform 2D packaging on a plurality of chips, and the packaged device still needs to be attached to a PCB to cooperate with other devices (such as power management, interface driving, I/O interface devices). And due to the limitation of the integration scale of the SIP and the restriction of partial function integration means, the SIP is still difficult to comprehensively solve the necessary requirements of systems such as heat dissipation, power supply, external interconnection, platform integration and the like, and cannot form an independent system.

Unlike SOC and SIP: the substrate used in the SOW is a whole semiconductor wafer, such as a 2-to 12-inch silicon wafer, the wafer is not diced, the wafer is wired by using an RDL process, active devices, such as switches, operational amplifiers, ADCs, logic unit circuits and the like, are prepared on the wafer according to system functions by using the semiconductor process, or the device is not prepared according to system application requirements, only RDL wiring is used, and the whole wafer is used for replacing the traditional substrate. The SOW runs through the whole process of integrated circuit design, processing and packaging, integrates advanced concepts such as prefabricated part assembly and wafer integration, and can realize the integration of thousands of prefabricated part particles such as sensing, radio frequency, calculation, storage, communication and the like on a single wafer by means of the remarkable advantages of high bandwidth, low delay, low power consumption and the like of wafer-level interconnection. By breaking boundary conditions such as a design method, a realization material and an integration mode of the existing integrated circuit, effectively breaking the performance limit of the current chip and breaking the ceiling effect of a key information infrastructure depending on a 'stacking type' engineering technical route, refreshing the technical physical form of the traditional equipment or system, enabling the comprehensive technical indexes of the system to obtain multiplicative gain, and meeting the sustainable development requirements of new generation infrastructures such as an intelligent era 5G, big data, a cloud platform, AI, edge computing, an intelligent network and the like.

However, constrained by the mechanical strength of the wafer and the RDL wiring rules, the difficulty in implementing large-sized SOW is an unprecedented challenge, mainly because although functional modules such as power management module, storage module, control module, interface IP module, etc. can be integrated on the wafer, peripheral circuits such as power management module, I/O connector, transduction sensor, display module, and mechanical transmission module still need to be integrated on the conventional PCB board, because the mechanical strength and the number of wiring layers of the PCB board are far better than those of the wafer. Therefore, in order to realize stable, reliable and efficient SOW operation, the advantages of the wafer circuit and the PCB circuit are combined, and the SOW and the PCB are integrated together to form a good solution. However, the PCB is easy to warp due to multiple factors such as inconsistent residual copper rate of the inner layer caused by wiring, asymmetric via holes on the front side and the back side, inconsistent laminated materials and thicknesses of all layers, different thermal expansion coefficients of the laminated sub-boards, easy bending of the board and the like.

Therefore, we propose the interconnection and heat dissipation structure of the wafer prefabricated component and the PCB and the manufacturing method thereof to solve the above technical problems.

Disclosure of Invention

The invention aims to provide an interconnection and heat dissipation structure of a wafer prefabricated part and a PCB (printed Circuit Board) and a manufacturing method thereof, which solve the problems that the warped PCB is fixed and flattened by a rigid cylinder of a rigid structural member, the information interaction between a large-size wafer and the PCB is solved by using a flexible connector, and the heat dissipation problem of the interconnection structure of the wafer prefabricated part and the PCB is solved by using air-cooled heat dissipation and micro channels of the structural member.

The technical scheme adopted by the invention is as follows:

the utility model provides an interconnection and heat radiation structure of wafer prefab and PCB board, includes the top structure, the top of top structure can be dismantled and be connected with the fan, the bottom of top structure can be dismantled and be connected with the bottom structure, the bottom of top structure is provided with the top recess, be provided with the PCB prefab in the recess of top, the top of bottom structure is provided with the bottom recess, be provided with the wafer prefab in the recess of bottom, connect through flexible connector between PCB prefab and the wafer prefab, the bottom of bottom structure still is provided with liquid cooling pipeline subassembly, the top of liquid cooling pipeline subassembly is run through the bottom structure and extend to in the recess of bottom with the wafer prefab is connected.

Furthermore, the fixed a plurality of hollow support column that is provided with of the interior roof of top recess, the interior roof of top recess still be provided with the mounting hole that hollow support column corresponds, the PCB prefab passes through the connecting piece in proper order the PCB prefab with hollow support column extends to the mounting hole with top groove connection.

Further, the PCB prefab includes PCB board, flexbile plate and pad, the PCB board passes through in proper order through the connecting piece the PCB board with hollow support column extends to the mounting hole with top groove connection, the lower surface equipartition of PCB board is provided with a plurality of the pad, the bottom of PCB board is provided with the flexbile plate, be provided with on the flexbile plate with the via hole that the pad corresponds, be provided with in the via hole the flexible connector, the top of flexible connector with the pad is connected, the bottom of flexible connector is connected the wafer prefab.

Further, the hollow support column is a hexagonal hollow copper column, a hexagonal hollow plastic column, a square hollow copper column, a square hollow plastic column, a cylindrical hollow copper column or a cylindrical hollow plastic column.

Further, the wafer prefab includes wafer, pressure welding point, miniflow channel, sealed rubber ring and joint, the wafer set up in the bottom recess, the upper surface of wafer be provided with flexible connector connects the pressure welding point, the inside that the wafer is close to the bottom is provided with the miniflow channel, the lower surface of wafer be provided with the miniflow channel zonulae occludens sealed rubber ring, the bottom of sealed rubber ring is connected the joint, the joint extends to in the bottom structure with liquid cooling pipeline assembly connects.

Further, liquid cooling pipeline subassembly includes hose and adapter, the bottom of bottom structure is provided with a plurality of through-holes, be provided with in the through-hole the hose, the bottom of hose is connected the adapter, the adapter set up in the lower surface of bottom structure, the top of hose is connected the wafer prefab.

Furthermore, positioning pins are uniformly distributed on the lower surface of the top structural part close to the end face, and positioning holes matched and connected with the positioning pins are uniformly distributed on the upper surface of the bottom structural part.

Furthermore, the upper surface of the top structural part is also provided with a heat dissipation groove and heat dissipation teeth.

Further, the top structural part and the bottom structural part are both metal structural parts, and the flexible connector is a micro spring, a hair button, an elastic needle or a winding inductor.

The invention also provides a manufacturing method of the interconnection and heat dissipation structure of the wafer prefabricated part and the PCB, which comprises the following steps:

step S1: welding a plurality of pressure welding points on the upper surface of the wafer, arranging a micro-channel in the wafer close to the bottom end, bonding a sealing rubber ring on the lower surface of the wafer and tightly connecting the sealing rubber ring with the micro-channel, and bonding a joint on the other surface of the sealing rubber ring to form a wafer prefabricated part;

step S2: the wafer prefabricated member is arranged in a bottom groove on the bottom structural member, a connector at the bottom end of the wafer prefabricated member is inserted into the through hole to be connected with the hose, the hose penetrates through the through hole and is externally connected with the adapter, and the adapter is fixed at the bottom end of the bottom structural member to form the bottom prefabricated member;

step S3: fixedly connecting the PCB with a top groove of a top structural member by sequentially penetrating through the PCB and the hollow support columns through connecting pieces and extending to the mounting holes, welding a plurality of bonding pads on the lower surface of the PCB, bonding the flexible board with the PCB through organic glue, and ensuring that via holes in the flexible board are aligned with the bonding pads on the PCB to form a top prefabricated member;

step S4: the flexible connector penetrates through a through hole in the flexible plate and is connected with the bonding pad, a positioning pin of a top structural member on the top prefabricated member is matched and connected with a positioning hole of a bottom structural member on the bottom prefabricated member, the other end of the flexible connector is connected with a pressure welding point on the wafer, and the flexible connector penetrates through the bottom prefabricated member through a plurality of connecting pieces and extends to the top prefabricated member to form an interconnected structural body;

step S5: and fixing the fan on the upper surface of the interconnected structure, and attaching the lower surface of the fan to the heat dissipation teeth on the upper surface of the top structural member to complete assembly.

The invention has the beneficial effects that: the invention utilizes the rigidity of the top structural member and the fine adjustment performance of the hollow support column to correct and improve the warping problem of the PCB caused by multiple times of high-temperature lamination, different residual copper rates on the front side and the back side, asymmetric inner layer routing and asymmetric via holes, so that the warping rate of the PCB is reduced by at least one order of magnitude, and the fundamental reason of the warping of the PCB is the inconsistent shrinkage caused by the difference of thermal expansion coefficients among laminated plates, copper sheets and copper wires. Because the wafer prefabricated part based on the micro-nano processing technology has high processing precision and complex processing flow, the line width can reach 14nm or less, the pressure welding point is only about 50um after Fan-out, and the silk-screen printing technology is a method for corroding thick copper sheets based on a wet method, and the size is more than 300um for ensuring the firmness of the bonding pad. Obviously, the micro-nano processing technology and the screen printing technology have obvious generation difference in processing precision, interconnection and intercommunication innovation is developed based on the screen printing circuit technology and the micro-nano technology, the two technologies are well combined together, and the PCB is fixed through a rigid structural member so as to greatly improve the warping of the PCB; the metal structural member is used as an integral support, so that damage to the wafer prefabricated member due to vibration and extrusion is eliminated; due to the telescopic characteristic of the flexible connector, interconnection failure of the PCB and the wafer prefabricated part caused by warping is avoided, and therefore the reliability of the whole assembly structure is remarkably improved; by adopting the micro-channel technology, the heat exchange capability of the wafer prefabricated part is obviously improved by utilizing the characteristic of large specific heat capacity of liquid, so that the working temperature of the wafer prefabricated part is greatly reduced; the surface area of a heat exchange area is increased through the heat dissipation teeth of the top structural part, and forced convection is performed by using a heat dissipation fan, so that the heat dissipation capacity of the PCB is improved, and the working temperature of the PCB is reduced. The invention solves the key technical problem of interconnection between the wafer prefabricated part and the traditional PCB from the technical aspect, and particularly can solve the problem of interconnection failure caused by the warping of the PCB; the connection and assembly technology of the wafer prefabricated part and the peripheral PCB is solved from the assembly and reliability level; the problems of high-density thermal power heat conduction and heat dissipation of the wafer prefabricated part are solved from the thermal management angle. Therefore, the invention can provide technical support for information exchange and provide reliable technical guarantee for the hybrid integration of the high-power and high-density wafer prefabricated part and the traditional screen printing circuit.

Drawings

FIG. 1 is a schematic view of the overall structure of the present invention;

FIG. 2 is an enlarged view of the invention at A;

FIG. 3 is an isometric view of the top structural member of the present invention in connection with a PCB preform;

FIG. 4 is a schematic isometric view of the bottom structure of the present invention in connection with a wafer preform;

FIG. 5 is a front view of a wafer preform and a micro flow channel structure according to an embodiment;

FIG. 6 is a top view of an embodiment of a wafer preform and micro flow channel structure;

FIG. 7 is a front view of a PCB board of an embodiment;

FIG. 8 is a top view of a PCB board of an embodiment;

FIG. 9 is a front view of the flexible board of the embodiment;

FIG. 10 is a top view of a flexible sheet of an embodiment;

FIG. 11 is a schematic diagram of a fan array according to an embodiment.

Description of the reference numerals

1-top structure, 11-top groove, 12-hollow support column, 13-mounting hole, 14-positioning pin, 15-heat dissipation groove, 16-heat dissipation tooth, 2-fan, 3-bottom structure, 31-bottom groove, 32-through hole, 33-positioning hole, 4-PCB prefabricated part, 41-PCB board, 42-flexible board, 421-through hole, 43-welding pad, 5-wafer prefabricated part, 51-wafer, 52-pressure welding point, 53-micro channel, 54-sealing rubber ring, 55-joint, 6-flexible connector, 7-liquid cooling pipeline component, 71-hose and 72-adapter.

Detailed Description

The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1-4, an interconnection and heat radiation structure of wafer prefabricated component and PCB board, includes top structure 1, the top of top structure 1 can be dismantled and be connected with fan 2, the bottom of top structure 1 can be dismantled and be connected with bottom structure 3, the bottom of top structure 1 is provided with top recess 11, be provided with PCB prefabricated component 4 in the top recess 11, the top of bottom structure 3 is provided with bottom recess 31, be provided with wafer prefabricated component 5 in the bottom recess 31, connect through flexible connector 6 between PCB prefabricated component 4 and the wafer prefabricated component 5, the bottom of bottom structure 3 still is provided with liquid cooling pipeline assembly 7, the top of liquid cooling pipeline assembly 7 runs through bottom structure 3 and extend to in the bottom recess 31 with wafer prefabricated component 5 is connected.

The fixed hollow support column 12 of a plurality of that is provided with of interior roof of top recess 11, the interior roof of top recess 11 still be provided with mounting hole 13 that hollow support column 12 corresponds, PCB prefab 4 runs through in proper order through the connecting piece PCB prefab 4 with hollow support column 12 extends to mounting hole 13 with top recess 11 is connected.

PCB prefab 4 includes PCB board 41, flexbile plate 42 and pad 43, PCB board 41 runs through in proper order through the connecting piece PCB board 41 with hollow support column 12 extends to mounting hole 13 with top recess 11 is connected, PCB board 41's lower surface equipartition is provided with a plurality of pad 43, PCB board 41's bottom is provided with flexbile plate 42, be provided with on the flexbile plate 42 with via hole 421 that pad 43 corresponds, be provided with in the via hole 421 flexible connector 6, flexible connector 6's top with pad 43 is connected, flexible connector 6's bottom is connected wafer prefab 5.

The hollow support column 12 is a hexagonal hollow copper column, a hexagonal hollow plastic column, a square hollow copper column, a square hollow plastic column, a cylindrical hollow copper column or a cylindrical hollow plastic column.

Wafer prefab 5 includes wafer 51, pressure welding point 52, miniflow channel 53, sealed rubber ring 54 and connects 55, wafer 51 set up in the bottom recess 31, wafer 51's upper surface be provided with flexible connector 6 connects pressure welding point 52, the inside that wafer 51 is close to the bottom is provided with miniflow channel 53, wafer 51's lower surface be provided with miniflow channel 53 zonulae occludens sealed rubber ring 54, sealed rubber ring 54's bottom is connected connect 55, connect 55 extend to in the bottom structure piece 3 with liquid cooling pipeline subassembly 7 connects.

Liquid cooling pipeline assembly 7 includes hose 71 and adapter 72, the bottom of bottom structure 3 is provided with a plurality of through-holes 32, be provided with in the through-hole 32 hose 71, the bottom of hose 71 is connected adapter 72, adapter 72 set up in the lower surface of bottom structure 3, the top of hose 71 is connected wafer prefab 5.

The lower surface of the top structural part 1 is uniformly provided with positioning pins 14 close to the end face, and the upper surface of the bottom structural part 3 is uniformly provided with positioning holes 33 matched and connected with the positioning pins 14.

The upper surface of the top structure 1 is also provided with heat dissipation grooves 15 and heat dissipation teeth 16.

The top structural part 1 and the bottom structural part 3 are both metal structural parts, and the flexible connector 6 is a micro spring, a hair button, an elastic needle or a winding inductor.

A manufacturing method of an interconnection and heat dissipation structure of a wafer prefabricated member and a PCB comprises the following steps:

step S1: welding a plurality of pressure welding points 52 on the upper surface of the wafer 51, arranging a micro-channel 53 in the wafer 51 close to the bottom end, bonding a sealing rubber ring 54 on the lower surface of the wafer 51 and tightly connecting the micro-channel 53, and bonding a joint 55 on the other surface of the sealing rubber ring 54 to form a wafer prefabricated part 5;

step S2: the wafer prefabricated member 5 is arranged in the bottom groove 31 on the bottom structural member 3, the joint 55 at the bottom end of the wafer prefabricated member 5 is inserted into the through hole 32 and connected with the hose 71, the hose 71 penetrates through the through hole 32 and is externally connected with the adapter 72, and the adapter 72 is fixed at the bottom end of the bottom structural member 3 to form a bottom prefabricated member;

step S3: the PCB 41 is fixedly connected with the top groove 11 of the top structural member 1 by sequentially penetrating through the PCB 41 and the hollow support columns 12 through connectors and extending to the mounting holes 13, a plurality of welding pads 43 are welded on the lower surface of the PCB 41, the flexible board 42 is bonded with the PCB 41 through organic glue, and the through holes 421 on the flexible board 42 are aligned with the welding pads 43 on the PCB 41 to form a top prefabricated member;

step S4: the flexible connector 6 penetrates through the through hole 421 on the flexible plate 42 and is connected with the bonding pad 43, the positioning pin 14 of the top structural member 1 on the top prefabricated member is matched and connected with the positioning hole 33 of the bottom structural member 3 on the bottom prefabricated member, the other end of the flexible connector 6 is connected with the pressure welding point 52 on the wafer 51, and penetrates through the bottom prefabricated member through a plurality of bolts and extends to the top prefabricated member, so that an interconnection structure body is formed;

step S5: the fan 2 is fixed on the upper surface of the interconnected structure through a plurality of screws, and the lower surface of the fan 2 is attached to the heat dissipation teeth 16 on the upper surface of the top structural member 1, so that the assembly is completed.

Example 1

Step S1: micro-nano processing technology is adopted to process micro-channels 53 on the back of a wafer prefabricated part 5, the technology of 0.18um or below 0.18um is used, the cross section of each micro-channel 53 is 0.2mm multiplied by 0.2mm, the thickness of the wafer prefabricated part 5 with the micro-channels 53 is 1.2mm, the reference of a picture 5-a picture 6 is shown, the distance between every two adjacent micro-channels 53 is 1.5mm, an array hole is arranged on an input/output interface, the array is 2 multiplied by 2, the distance is 1mm, then a sealing rubber ring 54 with the thickness of 2mm is bonded on the interface, the diameter of the sealing rubber ring 54 is 6mm, holes matched with the array hole are reserved, finally a liquid cooling joint is bonded on the sealing rubber ring 54, and the diameter of a joint 55 is 3.5mm, and the length is 6 mm.

Step S2: the 8-layer circuit board is manufactured by adopting a screen printing process, referring to fig. 7-8, the board is loose M4, the total thickness of the PCB 41 is 1mm, the lower surface is exposed with a plurality of bonding pads 43 to be connected with the wafer prefabricated part 5, the size is 0.4mm multiplied by 0.4mm, a plurality of fixing holes are formed, the diameter is 2.8mm, the warping rate of the molded PCB 41 is about 0.5%, and the size is 330mm multiplied by 330 mm.

Step S3: the bottom structure 3 is made of red copper, the overall dimension of the bottom structure 3 is 400mm multiplied by 30mm, the upper surface of the bottom structure 3 is processed to be matched with the size of 5 wafer prefabricated parts, the bottom groove 31 with the depth of 1.25-1.3mm is processed to be provided with four positioning holes 33 with the diameter of 1.5mm, the depth of 3mm is 3mm, a plurality of fixing holes with the diameter of 3.5mm are formed in the upper surface of the bottom structure, two through holes 32 are formed in the positions corresponding to the positions of the liquid cooling joints, the diameter of each through hole 32 is 5mm, a hose 71 is arranged in each through hole 32, the diameter of each hose 71 is 4mm, the upper end of each hose 71 is connected with the liquid cooling joints, and the lower end of each hose 71 is connected with a pipeline adapter 72.

Step S4: the top structural member 1 is made of red copper, and the external dimension of the top structural member 1 is 400mm multiplied by 30 mm. The lower surface processing of top structure 1 has the top recess 11 of 330.2mm X10.5 mm, and there are a plurality of screw holes that correspond with PCB board 41 top recess 11 bottom, and the screw hole specification is M2.5X 7 mm. Four positioning pins 14 corresponding to the positioning holes 33 are further processed at the bottom of the top structural member 1, and the size of each positioning pin 14 is phi 1.5 multiplied by 2 mm. The top structural part 1 is provided with an array of radiating teeth 16, the height of each radiating tooth 16 is 15mm, the width of each radiating tooth is 10mm, the width of each radiating groove 15 is 10mm, and the radiating teeth 16 and the radiating grooves 15 are arranged periodically. The top structural member 1 is provided with a plurality of M3 multiplied by 9mm fixing holes for fixing the cooling fan 2, the hole positions correspond to the screw holes of the cooling fan 2, the cooling fan 2 selects 4 products with 180mm multiplied by 180mm, and the wind power of the single fan 2 is not less than 300CFM, which is shown in figure 11.

Step S5: the PCB 41 of step S2 is fixed in the top groove 11 of the top structure 1 by using a plurality of M2.5 × 10mm pan head screws through a 6 mm-high hexagonal copper pillar, and then a small amount of glue is coated on the flexible board 42 with the number and position of through holes 32 with a diameter of 4.5mm corresponding to the PCB 41 and the number and position of through holes 32 with a diameter of 0.27mm corresponding to the number and position of the pressure welding points 52 on the upper surface of the wafer 51 of step S1, so as to align and attach the flexible board 42 and the PCB 41. The flexible sheet is seen in fig. 9-10.

Step S6: the wafer 51 prepared in step S1 is connected to a liquid-cooled joint using a hose 71 having an outer diameter of 4mm and an inner diameter of 3mm, and is loaded into the bottom structural member 3 prepared in step S3, and the wafer 51 is fixed with a heat conductive silicone grease, so that the hose 71 is inserted into the through hole 32 having a diameter of 5mm, and a pipe adapter 72 having a size matching the hose 71 exposed below is attached, and the adapter 72 is fixed to the bottom structural member 3, thereby forming the preform 1.

Step S7: several fuzz buttons with a diameter of 0.254mm and a length of 1.78mm are passed through the via 421 of the flexible board 42 and contacted with the pad 43 of the PCB board 41, and care is taken to check if there are any omissions, forming the preform 2.

Step S8: the

preforms

1 and 2 of the

steps

6 and 7 are aligned with the positioning holes 33 through the positioning pins 14, are attached together and fixed by using a plurality of screws M3X 36mm to form an assembly.

Step S9: the assembly is completed by mounting four fans 2 with M3 screws on top of the assembly at step 8.

For a more detailed comparison of the effects before and after the implementation, see table 1, table 1 shows the change of the warpage rate of the PCB 41, the warpage of the wafer preform 5, the height difference formed by the bonding of the PCB 41 and the wafer preform 5, the working temperature of the wafer preform 5 before and after the heat dissipation by the micro flow channel 53, the working temperature of the PCB 41 before and after the heat dissipation by the fan 2, and the reliability of the electrical connection. From table 1, it can be seen that, after the PCB 41 is fixed to the top structural member 1, the warpage rate is reduced from 0.5% to 0.05%, and the warpage height difference is only 0.165 mm. The wafer preform 5 has micro channels 53 on the back surface, RDL layers and pressure welding points 52 on the front surface, and thermal stress release exists on both the front surface and the back surface, but the directions are just opposite, so that the warpage rate is small, only 0.03%, and the height difference is 0.092 mm. As can be seen from table 1, after the micro flow channel 53 heat dissipation technology is used, the working temperature of the wafer preform 5 is significantly reduced, the bearable thermal power is higher, and the working temperature of the PCB 41 is also reduced by 20 degrees under the actions of the heat dissipation grooves 15 and the heat dissipation teeth 16 of the top structural member 1 and the heat dissipation fan 2.

TABLE 1 comparison of the examples

Referring to table 2, the total warpage of the PCB processed by the first line PCB manufacturing factory at home and abroad according to the factors of the laminated board, the routing, the via hole, the copper thickness and the like is 0.25% -1%, and the warpage of the hybrid board with a large-size complex structure is more than 0.5%.

TABLE 2 certain PCB manufacturer processing Capacity

Table 2 shows the processing capability of a PCB manufacturing factory, and it can be seen from the table that the defects of low precision of the printed circuit manufacturing process, especially large tolerance of the pad and the line width, large warpage of the board, etc., make it difficult to fuse with the wafer preform based on the micro-nano processing process, and become a key technical problem of the SOW technology.

In summary, the present invention can solve the interconnection and intercommunication problem between the large-sized wafer preform 5 and the warped PCB 41, and can also solve the heat dissipation problem of the wafer 51 and the heat dissipation problem of the PCB 41, thereby providing a technical support for the high-power wafer 51 and the fast and stable information exchange between the wafer 51 and the PCB 41.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The utility model provides an interconnection and heat radiation structure of wafer prefab and PCB board, a serial communication port, including top structure spare (1), the top of top structure spare (1) can be dismantled and be connected with fan (2), the bottom of top structure spare (1) can be dismantled and be connected with bottom structure spare (3), the bottom of top structure spare (1) is provided with top recess (11), be provided with PCB prefab (4) in top recess (11), the top of bottom structure spare (3) is provided with bottom recess (31), be provided with wafer prefab (5) in bottom recess (31), connect through flexible connector (6) between PCB prefab (4) and the wafer prefab (5), the bottom of bottom structure spare (3) still is provided with liquid cooling pipeline subassembly (7), the top of liquid cooling pipeline subassembly (7) is run through bottom structure spare (3) and extend to in bottom recess (31) with the prefabricated wafer prefab The pieces (5) are connected.

2. A structure for interconnecting and dissipating heat of a wafer preform and a PCB as claimed in claim 1, wherein a plurality of hollow supporting pillars (12) are fixedly disposed on an inner top wall of the top groove (11), a mounting hole (13) corresponding to the hollow supporting pillars (12) is further disposed on the inner top wall of the top groove (11), and the PCB preform (4) sequentially penetrates through the PCB preform (4) and the hollow supporting pillars (12) through a connecting member and extends to the mounting hole (13) to be connected with the top groove (11).

3. The wafer pre-form and PCB interconnection and heat dissipation structure as claimed in claim 2, characterized in that the PCB prefabricated part (4) comprises a PCB board (41), a flexible board (42) and a bonding pad (43), the PCB (41) sequentially penetrates through the PCB (41) and the hollow supporting column (12) through a connecting piece, extends to the mounting hole (13) and is connected with the top groove (11), the lower surface of the PCB (41) is uniformly provided with a plurality of bonding pads (43), the bottom end of the PCB (41) is provided with the flexible board (42), the flexible board (42) is provided with a via hole (421) corresponding to the bonding pad (43), the flexible connector (6) is arranged in the through hole (421), the top end of the flexible connector (6) is connected with the bonding pad (43), the bottom end of the flexible connector (6) is connected with the wafer prefabricated member (5).

4. A wafer preform and PCB board interconnection and heat dissipation structure as claimed in any of claims 2-3, wherein the hollow support pillar (12) is a hexagonal hollow copper pillar, a hexagonal hollow plastic pillar, a square hollow copper pillar, a square hollow plastic pillar, a cylindrical hollow copper pillar or a cylindrical hollow plastic pillar.

5. The wafer pre-form and PCB interconnection and heat dissipation structure as claimed in claim 1, characterized in that the wafer prefabricated part (5) comprises a wafer (51), a pressure welding point (52), a micro-channel (53), a sealing rubber ring (54) and a joint (55), the wafer (51) is arranged in the bottom groove (31), the upper surface of the wafer (51) is provided with the pressure welding points (52) connected with the flexible connector (6), the micro-channel (53) is arranged in the wafer (51) close to the bottom end, the lower surface of the wafer (51) is provided with the sealing rubber ring (54) tightly connected with the micro flow channel (53), the bottom end of the sealing rubber ring (54) is connected with the joint (55), and the joint (55) extends into the bottom structural part (3) and is connected with the liquid cooling pipeline assembly (7).

6. The wafer preform and PCB interconnecting and heat dissipating structure of claim 1, wherein the liquid cooling pipeline assembly (7) comprises a hose (71) and an adapter (72), a plurality of through holes (32) are formed in the bottom end of the bottom structural member (3), the hose (71) is disposed in the through holes (32), the adapter (72) is connected to the bottom end of the hose (71), the adapter (72) is disposed on the lower surface of the bottom structural member (3), and the top end of the hose (71) is connected to the wafer preform (5).

7. The interconnection and heat dissipation structure of a wafer preform and a PCB as claimed in claim 1, wherein the lower surface of the top structural member (1) is uniformly provided with positioning pins (14) near the end surface, and the upper surface of the bottom structural member (3) is uniformly provided with positioning holes (33) engaged with the positioning pins (14).

8. A wafer preform to PCB interconnection and heat dissipation structure as claimed in claim 1, wherein the top structure (1) is further provided with heat dissipation grooves (15) and heat dissipation teeth (16) on its upper surface.

9. The interconnection and heat dissipation structure of a wafer preform and a PCB board as claimed in claim 1, wherein the top structural member (1) and the bottom structural member (3) are both metal structural members, and the flexible connector (6) is a micro spring, a hair button, an elastic needle or a wound inductor.

10. A method for manufacturing a structure for interconnecting a wafer preform and a PCB and dissipating heat therefrom according to any one of claims 1 to 9, comprising the steps of:

step S1: welding a plurality of pressure welding points (52) on the upper surface of a wafer (51), arranging a micro-channel (53) in the wafer (51) close to the bottom end, bonding a sealing rubber ring (54) on the lower surface of the wafer (51) and tightly connecting the sealing rubber ring with the micro-channel (53), and bonding a joint (55) on the other surface of the sealing rubber ring (54) to form a wafer prefabricated part (5);

step S2: the method comprises the following steps of (1) loading a wafer prefabricated part (5) into a bottom groove (31) on a bottom structural part (3), inserting a joint (55) at the bottom end of the wafer prefabricated part (5) into a through hole (32) to be connected with a hose (71), enabling the hose (71) to penetrate through the through hole (32) and be externally connected with an adapter (72), and fixing the adapter (72) at the bottom end of the bottom structural part (3) to form the bottom prefabricated part;

step S3: the PCB (41) and a top groove (11) of the top structural component (1) are fixedly connected by sequentially penetrating through the PCB (41) and the hollow support column (12) through a connecting piece and extending to the mounting hole (13), a plurality of welding pads (43) are welded on the lower surface of the PCB (41), the flexible plate (42) is bonded with the PCB (41) through organic glue, and the through hole (421) in the flexible plate (42) is aligned with the welding pads (43) in the PCB (41) to form a top prefabricated part;

step S4: the method comprises the steps that a flexible connector (6) penetrates through a through hole (421) in a flexible plate (42) and is connected with a bonding pad (43), a positioning pin (14) of a top structural component (1) on a top prefabricated component is matched and connected with a positioning hole (33) of a bottom structural component (3) on a bottom prefabricated component, the other end of the flexible connector (6) is connected with a pressure welding point (52) on a wafer (51), and the flexible connector penetrates through the bottom prefabricated component through a plurality of connecting pieces and extends to the top prefabricated component to form an interconnection structure body;

step S5: and fixing the fan (2) on the upper surface of the interconnected structure, and attaching the lower surface of the fan (2) to the heat dissipation teeth (16) on the upper surface of the top structural member (1) to complete assembly.