Wafer level packaging reflow soldering anti-warping self-adaptive reinforcing device and method

Abstract

The invention belongs to the technical field of reflow soldering, and particularly relates to a wafer-level packaging reflow soldering anti-warping self-adaptive reinforcing device and a wafer-level packaging reflow soldering anti-warping self-adaptive reinforcing method. Comprising a supporting platform used for bearing a wafer-level substrate assembly to be subjected to reflow soldering; the spring floating supporting mechanisms are arranged in the concave cavity of the supporting platform in a multi-point manner, are used for supporting the wafer-level substrate assembly to be subjected to reflow soldering, and have a certain floating stroke; each spring floating supporting mechanism is composed of elastic elements arranged in a multi-point mode. And the grating type pressing mechanism is positioned above the supporting platform, consists of a plurality of orthogonal rigid pressing rods, and forms a latticed pressing surface covering the effective area of the substrate. The method aims at effectively restraining buckling deformation of the wafer-level substrate caused by thermal stress in the reflow soldering process, and the coplanarity and stability of a soldering interface are ensured.

Description

Technical Field

[0001] This invention belongs to the field of reflow soldering technology, and specifically relates to a wafer-level packaging reflow soldering anti-warping adaptive reinforcement device and method. Background Technology

[0002] As Moore's Law slows down and performance improvements in traditional single-chip applications become limited, technologies such as heterogeneous integration are reshaping the design paradigm for high-performance computing and AI accelerators. Wafer-level packaging (WLP) is an advanced packaging technology that enables wafer-level system integration. It integrates multiple chips, devices, and functional modules onto a single wafer-level substrate, breaking through the limitations of single-chip size and interconnection to achieve high-density heterogeneous integration.

[0003] In the core process flow of wafer-level packaging, reflow soldering is a critical step to ensure reliable connection between the chip and the substrate. The solder bumps on the bottom of the chip are melted, wetted, and solidified during reflow soldering, forming the electrical and mechanical interconnects between the chip and the wafer-level substrate. The composite structure formed by the silicon chip, the polymer dielectric / metal of the redistribution layer (RDL), the underfill material, and the wafer-level substrate is subjected to severe thermal loads (peak temperatures reaching 240℃~260℃) during reflow soldering. Due to the mismatch in thermal expansion coefficients of the different materials, the overall structure generates significant thermomechanical stress. The 12-inch wafer-level substrate is a crucial carrier for devices and interconnects. When the thermal stress exceeds the material's yield strength, the organic substrate often exhibits a "V"-shaped warping under gravity due to the localized thermal stress contraction effect. This can lead to failures such as poor solder joints, excessive localized stress causing pin tearing, and other issues.

[0004] Wafer-level substrate warping leads to decreased mounting quality, poor solder joint coplanarity, and problems such as cold solder joints, bridging, and uneven solder ball height, resulting in reduced yield. Excessive stress concentration at weak points such as chip edges can cause brittle chip cracking, solder joint fatigue failure, and interconnect structure breakage. For substrates with complex structures, excessive local stress can cause substrate material tearing or delamination, posing a systemic and multi-layered severe challenge to subsequent precision manufacturing processes such as chip mounting. Conventional clamping structures include traditional rigid fixtures and vacuum adsorption carriers. Since vacuum sealing is difficult at high temperatures, and adsorption forces can cause localized stress and deformation, affecting the reflow soldering quality of the substrate, traditional rigid fixtures cannot adapt to the slight expansion / contraction of the substrate during heating. Instead, they introduce additional stress, exacerbating local damage or causing fixture deformation, uneven pressure distribution, and easily scratching devices on the substrate surface.

[0005] With the increasing demand for wafer-level packaging, there is an urgent need for a reinforcement technology that can adaptively apply uniform and controllable pressure in high-temperature environments and provide effective structural support to effectively suppress wafer-level substrate warpage while avoiding the introduction of additional stress, thereby reducing the risk of warpage failure during the reflow soldering process. Summary of the Invention

[0006] The purpose of this invention is to provide a wafer-level packaging reflow soldering anti-warping adaptive reinforcement device and method. This invention applies a controllable and uniform bearing force to the wafer-level substrate assembly during reflow soldering to compensate for and counteract thermal stress caused by mismatched coefficients of thermal expansion. This effectively suppresses warping deformation of the wafer-level substrate caused by thermal stress during reflow soldering, ensuring the coplanarity and stability of the solder interface. This reinforcement device is compatible with existing reflow soldering equipment, is easy to operate and disassemble, and reduces the risk of damage to devices on the substrate surface.

[0007] To address the aforementioned technical problems, this invention provides a wafer-level packaging reflow soldering anti-warpage adaptive hardening device, comprising:

[0008] Support platform, used to support wafer-level substrate assemblies to be reflow soldered;

[0009] A spring-loaded floating support mechanism is arranged at multiple points within the cavity of the support platform to provide support for the wafer-level substrate assembly to be reflow soldered, and has a certain floating stroke. Each spring-loaded floating support mechanism is composed of multiple elastic elements, each elastic element including: a high-temperature resistant disc spring, a high-temperature resistant pin, and a support block. One end of the high-temperature resistant pin is floatingly inserted into the bottom wall of the cavity, and the other end is threaded and locked onto the support block. The high-temperature resistant disc spring is sleeved on the high-temperature resistant pin, and the upper and lower ends of the high-temperature resistant disc spring abut against the support block and the cavity, respectively.

[0010] The grid-type clamping mechanism, located above the support platform, consists of multiple orthogonal rigid pressure bars, forming a grid-like clamping surface that covers the effective area of ​​the substrate.

[0011] Preferably, the support platform is an octagonal base with a central cavity, and its material is 304 stainless steel; its bottom is a flat surface that can integrate a heat dissipation plate.

[0012] Preferably, the bottom of the cavity of the support platform is provided with a plurality of cylindrical countersunk holes for inserting the high-temperature resistant pins, and the high-temperature resistant pins and the cylindrical countersunk holes are positioned with negative tolerance to ensure that the high-temperature resistant pins can float vertically.

[0013] Preferably, each of the spring floating support mechanisms consists of 5 elastic elements distributed in a "four corners and center point" manner, wherein each support point has an independent floating stroke of 0 to 5 mm, and the high-temperature resistant disc spring adopts a bimetallic compensating spring, which can compensate for the influence of temperature on the spring stiffness.

[0014] Preferably, the grid-type clamping mechanism includes: a transverse clamping rod, a longitudinal clamping rod, and a tail fin clamping rod; two spaced transverse clamping rods and two spaced longitudinal clamping rods are orthogonally clamped together, and four tail fin clamping rods are respectively clamped to the ends of the transverse clamping rods and the longitudinal clamping rods. Through the cross arrangement between the transverse clamping rods, the longitudinal clamping rods, and the tail fin clamping rods, a multi-grid grid-type clamping structure is formed.

[0015] Preferably, it further includes flexible gaskets, which are disposed at the bottom of the lateral pressure bar, the longitudinal pressure bar, and the tail fin pressure bar, and are made of Mylar sheet with high temperature resistance, low modulus, and high elasticity; the lateral pressure bar, the longitudinal pressure bar, and the tail fin pressure bar are made of ceramic matrix composite material with high strength, low coefficient of thermal expansion, and high temperature resistance.

[0016] Preferably, it also includes U-shaped grooves and through holes. Each of the transverse pressure rods, the longitudinal pressure rods, and the tail fin pressure rods is linearly provided with a plurality of U-shaped grooves. The through holes are provided in the U-shaped grooves. The transverse pressure rods and the longitudinal pressure rods, the transverse pressure rods and the tail fin pressure rods, and the longitudinal pressure rods and the tail fin pressure rods are snapped and locked together through the U-shaped grooves and the through holes. At the same time, the diameter of the multi-grid of the grid-type clamping structure can be flexibly adjusted according to the area where the components to be soldered on the wafer-level substrate assembly to be reflow soldered are required to be placed.

[0017] Preferably, it further includes a first fixing screw, a second fixing screw, and a third fixing screw with a self-locking structure; the first fixing screw is used to be inserted sequentially from the bottom into the preset hole of the substrate and the through hole on the U-shaped groove at the connection point between the transverse pressure rod and the longitudinal pressure rod, and a nut is tightened at the end of the first fixing screw to pre-tighten the transverse pressure rod, the longitudinal pressure rod, and the substrate; at the same time, an elastic washer is also included between the first fixing screw and the longitudinal pressure rod; the second fixing screw is used to be inserted sequentially from the top into the connection between the tail wing pressure rod and the transverse pressure rod. The through holes on the U-shaped groove at the connection point, the preset holes on the substrate, and the locking screw holes on the support platform, as well as the through holes on the U-shaped groove at the connection point between the tail wing pressure rod and the longitudinal pressure rod, are used to pre-tighten the transverse pressure rod, the tail wing pressure rod and the substrate, and the longitudinal pressure rod, the tail wing pressure rod and the substrate, respectively; the ends of the transverse pressure rod, the longitudinal pressure rod and the tail wing pressure rod are pre-tightened to the locking screw holes of the support platform by the fixing screws.

[0018] Preferably, it further includes a clamping force application mechanism, which is a fastening fixture driven by a servo motor, used to apply pre-tightening action to the first fixing screw, the second fixing screw, and the third fixing screw; at the same time, the fastening fixture driven by the servo motor also includes a force measurement sensor, used to determine whether the clamping force reaches a preset threshold; it also includes limiting blocks, a plurality of the limiting blocks are respectively arranged on the substrate, used to abut against the bottom ends of the transverse pressure bar and the longitudinal pressure bar, so as to prevent excessive clamping force from damaging the wafer-level substrate.

[0019] This invention also provides a reinforcement method for a wafer-level packaging reflow soldering anti-warpage adaptive reinforcement device, employing the wafer-level packaging reflow soldering anti-warpage adaptive reinforcement device as described above, comprising:

[0020] Place the component to be soldered at the corresponding location on the wafer-level substrate;

[0021] A floating spring support mechanism is installed on a support platform, and a clamping force application mechanism is used to press the wafer-level substrate onto the grid-type clamping mechanism.

[0022] A grid-type clamping mechanism that clamps the wafer-level substrate is placed on a support platform, and a pre-tightening force is applied by a clamping force application mechanism to complete the pre-tightening with the support platform.

[0023] The high-temperature resistant disc spring is compressed to a predetermined working stroke, so that the bottom surface of the grid-type clamping mechanism is in uniform contact with the substrate surface to ensure flat constraint in the initial state.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] This invention mounts the wafer-level substrate to be reflow soldered onto a support platform. A grid-type clamping mechanism secures the wafer-level substrate with the preload of a clamping force application mechanism. A bottom disc spring floating structure adaptively compensates for uneven local thermal stress during the reflow soldering process, effectively suppressing substrate deformation and warping caused by thermal stress and maintaining the overall structural flatness. The reinforcement device proposed in this invention can solve failures such as substrate warping caused by thermal stress during wafer-level reflow soldering, is compatible with wafer-level reflow soldering for various packages, is easy to install and remove, and improves the soldering reliability of wafer-level packages. Attached Figure Description

[0026] Figure 1 This is a three-dimensional structural view of a wafer-level packaging reflow soldering anti-warping adaptive reinforcement device according to the present invention.

[0027] Figure 2 This is a top view of the structure of a wafer-level packaging reflow soldering anti-warping adaptive reinforcement device according to the present invention.

[0028] Figure 3 This is a top view of the structure of a wafer-level packaging reflow soldering anti-warping adaptive reinforcement device according to the present invention.

[0029] Figure 4 This is a cross-sectional view of the structure of a wafer-level packaging reflow soldering anti-warpage adaptive reinforcement device according to the present invention. Figure 1 .

[0030] Figure 5 This is a cross-sectional view of the structure of a wafer-level packaging reflow soldering anti-warpage adaptive reinforcement device according to the present invention. Figure 2 .

[0031] Figure 6 This is a structural diagram of the support platform, spring floating support mechanism, and grid-type clamping mechanism of the present invention.

[0032] Figure 7 This is a top view of the structure of the spring floating support mechanism and the grid-type clamping mechanism of the present invention.

[0033] Figure 8 This is a top view of the structure of the spring floating support mechanism and the grid-type clamping mechanism of the present invention.

[0034] Figure 9 This is a structural diagram of the U-shaped groove and through hole of the present invention.

[0035] Figure 10 This is an exploded top view of the structure of a wafer-level packaging reflow soldering anti-warping adaptive reinforcement device of the present invention.

[0036] Figure 11This is an exploded bottom view of the structure of a wafer-level packaging reflow soldering anti-warping adaptive reinforcement device according to the present invention.

[0037] Figure 12 This is a flowchart illustrating the reinforcement process of an adaptive reinforcement device for preventing warpage during reflow soldering in wafer-level packaging, as described in this invention.

[0038] In the diagram: 1-Support platform, 11-Cavity, 12-Columnar countersunk hole, 2-Wafer-level substrate assembly to be reflow soldered, 21-Substrate, 22-Components, 3-Spring floating support mechanism, 31-Elastic element, 311-High temperature resistant pin, 312-Support block, 4-Grid-type clamping mechanism, 41-Transverse pressure bar, 42-Vertical pressure bar, 43-Tail wing pressure bar, 44-U-shaped pressure groove, 45-Through hole, 46-Fixing screw one, 461-Nut, 462-Elastic washer, 47-Fixing screw two, 48-Fixing screw three. Detailed Implementation

[0039] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The advantages and features of the present invention will become clearer from the following description. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of the present invention.

[0040] like Figures 1-12 As shown, this embodiment of the invention specifically provides a wafer-level packaging reflow soldering anti-warpage adaptive hardening device, comprising:

[0041] Support platform 1 is used to support wafer-level substrate assembly 2 to be reflow soldered; wafer-level substrate assembly 2 to be reflow soldered typically includes substrate 21 and devices to be soldered.

[0042] The spring floating support mechanism 3 is arranged in multiple points within the cavity 11 of the support platform 1. In this embodiment of the invention, eight spring floating support mechanisms 3 are specifically arranged to provide support for the wafer-level substrate assembly 2 to be reflow soldered and have a certain floating stroke. Each spring floating support mechanism 3 is composed of elastic elements 31 arranged in multiple points. Each elastic element 31 includes: a high-temperature resistant disc spring, a high-temperature resistant pin 311, and a support block 312. One end of the high-temperature resistant pin 311 is floatingly inserted into the bottom wall of the cavity 11, and the other end is threaded and locked onto the support block 312. A high-temperature resistant disc spring is sleeved on the high-temperature resistant pin 311, and the upper and lower ends of the high-temperature resistant disc spring abut against the support block 312 and the cavity 11, respectively.

[0043] The grid-type clamping mechanism 4 is located above the support platform 1 and consists of multiple orthogonal rigid pressure bars, forming a grid-like clamping surface that covers the effective area of ​​the substrate 21.

[0044] As a further explanation of the embodiments of the present invention, the support platform 1 is an octagonal base with a central cavity 11, which is made of 304 stainless steel; the surface is treated with oxidation and corrosion resistance, and the bottom is a flat surface that can integrate heat dissipation devices such as heat dissipation plates.

[0045] As a further explanation of the embodiments of the present invention, the bottom of the cavity 11 of the support platform 1 is provided with a plurality of cylindrical countersunk holes 12 for inserting high-temperature resistant pins 311. The high-temperature resistant pins 311 and the cylindrical countersunk holes 12 are positioned with negative tolerance, which can ensure that the high-temperature resistant pins 311 can float vertically and avoid jamming.

[0046] As a further explanation of the embodiments of the present invention, each spring floating support mechanism 3 is composed of 5 elastic elements 31 distributed in the manner of "four corners and center point". Each spring floating support mechanism 3 has an independent floating stroke of 0 to 5 mm at its support point. The high-temperature resistant disc spring adopts a bimetallic compensating spring, which can compensate for the influence of temperature on the spring stiffness.

[0047] As a further explanation of the embodiments of the present invention, the grid-type pressing mechanism 4 includes: a transverse pressing rod 41, a longitudinal pressing rod 42, and a tail wing pressing rod 43; two spaced transverse pressing rods 41 and two spaced longitudinal pressing rods 42 are orthogonally clamped together, and four tail wing pressing rods 43 are respectively clamped to the ends of the transverse pressing rods 41 and the longitudinal pressing rods 42. Through the cross arrangement between the transverse pressing rods 41, the longitudinal pressing rods 42, and the tail wing pressing rods 43, a multi-grid grid-type pressing structure is formed.

[0048] As a further illustration of the embodiments of the present invention, flexible gaskets are also included. The flexible gaskets are arranged at the bottom of the transverse pressure bar 41, the longitudinal pressure bar 42, and the tail fin pressure bar 43. The flexible gaskets are made of Mylar sheet, which is resistant to high temperature, has low modulus, and is highly elastic. They can buffer the surface pressing force and prevent the rigid connection from damaging the surface of the wafer-level substrate 21. Moreover, the Mylar sheet has the same shape as the pressure bar size to maintain flexible pressing on the wafer-level substrate 21. The transverse pressure bar 41, the longitudinal pressure bar 42, and the tail fin pressure bar 43 are made of ceramic matrix composite material with high strength, low coefficient of thermal expansion, and high temperature resistance.

[0049] As a further explanation of the embodiments of the present invention, it also includes U-shaped pressure grooves 44 and through holes 45. Each transverse pressure bar 41, longitudinal pressure bar 42 and tail wing pressure bar 43 is linearly provided with a plurality of U-shaped pressure grooves 44. Through holes 45 are provided on the U-shaped pressure grooves 44. The transverse pressure bar 41 and longitudinal pressure bar 42, the transverse pressure bar 41 and tail wing pressure bar 43, and the longitudinal pressure bar 42 and tail wing pressure bar 43 are snapped and locked together by the U-shaped pressure grooves 44 and through holes 45. At the same time, the diameter of the multi-grid of the grid-type clamping structure can be flexibly adjusted according to the area where the components 22 to be soldered on the wafer-level substrate assembly 2 to be reflow soldered are required to be placed. The grid is a spliced ​​assembly and can be freely disassembled and assembled according to the layout of the components 22 of the on-chip system.

[0050] As a further explanation of the embodiments of the present invention, it also includes a first fixing screw 46, a second fixing screw 47, and a third fixing screw 48 with a self-locking structure; the first fixing screw 46 is used to be inserted from the bottom into the pre-set hole of the substrate 21, the through hole 45 on the U-shaped pressure groove 44 at the connection point between the transverse pressure bar 41 and the longitudinal pressure bar 42, and the nut 461 is locked at the end of the first fixing screw 46 to pre-tighten the transverse pressure bar 41, the longitudinal pressure bar 42 and the substrate 21; at the same time, an elastic washer 462 is also included between the first fixing screw 46 and the longitudinal pressure bar 42 to avoid damaging the surface of the substrate 21; the second fixing screw 47 is used to be inserted from the top into the substrate 21. The through holes 45 on the U-shaped groove 44 at the connection point between the tail wing pressure rod 43 and the lateral pressure rod 41, the preset holes of the base plate 21 and the locking screw holes of the support platform 1, and the through holes 45 on the U-shaped groove 44 at the connection point between the tail wing pressure rod 43 and the longitudinal pressure rod 42, the preset holes of the base plate 21 and the locking screw holes of the support platform 1 are inserted to pre-tighten the lateral pressure rod 41, the tail wing pressure rod 43 and the base plate 21, and the longitudinal pressure rod 42, the tail wing pressure rod 43 and the base plate 21, respectively; the ends of the lateral pressure rod 41, the longitudinal pressure rod 42 and the tail wing pressure rod 43 are pre-tightened to the locking screw holes of the support platform 1 by fixing screws 48.

[0051] As a further explanation of the embodiments of the present invention, it also includes a clamping force application mechanism, which adopts a fastening fixture driven by a servo motor for applying pre-tightening action to fixing screw 46, fixing screw 47, and fixing screw 48; at the same time, the fastening fixture driven by the servo motor also includes a force value measuring sensor for determining whether the clamping force reaches a preset threshold, ensuring that the grid-type clamping mechanism 4 and the support platform 1 tightly press the wafer-level substrate 21 together; it also includes limiting blocks, with multiple limiting blocks respectively arranged on the substrate 21 for abutting against the bottom ends of the transverse pressure bar 41 and the longitudinal pressure bar 42 to prevent excessive clamping force from damaging the wafer-level substrate 21; the limiting blocks and the force value measuring sensor ensure the accuracy of the pre-tightening force, and the fixing screws include a self-locking structure to prevent the fixing screws from loosening and falling off due to thermal stress during reflow soldering.

[0052] This invention also provides a reinforcement method for a wafer-level packaging reflow soldering anti-warpage adaptive reinforcement device, employing the aforementioned wafer-level packaging reflow soldering anti-warpage adaptive reinforcement device, comprising:

[0053] Place the component 22 to be soldered at the corresponding position on the wafer-level substrate 21;

[0054] The floating spring support mechanism is installed on the support platform 1, and the wafer-level substrate 21 is pressed onto the grid-type clamping mechanism 4 by the clamping force application mechanism;

[0055] The grid-type clamping mechanism 4, which clamps the wafer-level substrate 21, is placed on the support platform 1, and a pre-tightening force is applied by the clamping force application mechanism to complete the pre-tightening with the support platform 1.

[0056] The high-temperature resistant disc spring is compressed to a predetermined working stroke, so that the bottom surface of the grid-type clamping mechanism 4 is in uniform contact with the surface of the substrate 21 to ensure flat constraint in the initial state.

[0057] As a further illustration of an embodiment of the present invention, the wafer to be reflowed is placed in a reflow oven. As the temperature rises, the organic substrate 21 begins to warp due to thermal stress (local areas attempt to bulge upwards or downwards). When a certain area of ​​the substrate 21 attempts to bulge upwards: the pressure head corresponding to that area (i.e., the pressing area of ​​the Mylar sheet) feels increased pressure. If the pressure exceeds a preset safety threshold, the spring floating support mechanism 3 below it is compressed, allowing the support point in that area to move slightly downwards, thereby releasing some pressure and preventing excessive compression that could damage the device or tear the substrate 21. The reaction force of the spring provides sufficient constraint to suppress excessive upward bulging.

[0058] When a certain area of ​​the substrate 21 attempts to be recessed: the pressure of the pressure head corresponding to that area decreases. At this time, the spring floating support mechanism 3 corresponding to that area extends, pushing the support point slightly upward, restoring or maintaining the clamping force on that area, and preventing it from being excessively recessed.

[0059] Throughout the entire heating-holding-cooling reflow soldering temperature profile, the device, through the linkage support of the spring floating support mechanism 3, achieves adaptive following of the warpage deformation of the substrate 21 and dynamic compensation of the clamping force. It maintains a relatively uniform and safe constraint force on the substrate 21 as a whole, effectively suppressing warpage while avoiding localized stress concentration. It can flexibly adapt to various wafer-level substrate 21 reflow soldering packaging layouts, improving the soldering quality and packaging reliability of wafer-level reflow soldering.

[0060] The above description is merely a description of preferred embodiments of the present invention and is not intended to limit the scope of the present invention in any way. Any changes or modifications made by those skilled in the art based on the above disclosure shall fall within the protection scope of the claims.

Claims

1. A wafer level package reflow soldering anti-warping self-adaptive reinforcement device, characterized in that, It comprises: a support platform (1) for carrying a wafer-level substrate assembly (2) to be reflow soldered; a spring floating support mechanism (3) arranged at multiple points in a cavity (11) of the support platform (1) for providing support to the wafer-level substrate assembly (2) to be reflow soldered and having a certain floating stroke; wherein each spring floating support mechanism (3) is composed of multiple-point arranged elastic elements (31), and each elastic element (31) comprises a high-temperature-resistant disc spring, a high-temperature-resistant pin (311) and a support block (312); one end of the high-temperature-resistant pin (311) is floatingly inserted into the bottom wall of the cavity (11), and the other end is threadedly locked to the support block (312), the high-temperature-resistant disc spring is sleeved on the high-temperature-resistant pin (311), and the upper and lower ends of the high-temperature-resistant disc spring are respectively in abutment with the support block (312) and the cavity (11); a grid type pressing mechanism (4) located above the support platform (1) and composed of multiple orthogonal rigid pressing rods to form a grid-shaped pressing surface covering the effective area of the substrate (21).

2. A wafer level package reflow soldering anti-warping self-adapting reinforcement device according to claim 1, characterized in that, The support platform (1) is a regular octagonal base with a cavity (11) in the center, and the material is 304 stainless steel; the bottom is a flat surface and can be integrated with a heat dissipation cold plate.

3. A wafer level package reflow soldering anti-warping self-adapting reinforcement device according to claim 2, characterized in that, The bottom of the cavity (11) of the support platform (1) is provided with a plurality of cylindrical counterbores (12) for inserting the high-temperature-resistant pins (311), and the high-temperature-resistant pins (311) and the cylindrical counterbores (12) are positioned with negative tolerance, which can ensure that the high-temperature-resistant pins (311) can float vertically.

4. A wafer level package reflow soldering anti-warping self-adapting reinforcement device according to claim 1, characterized in that, Each spring floating support mechanism (3) is composed of five elastic elements (31) distributed in a "four corners and center point" manner, wherein each support point has an independent floating stroke of 0-5mm, the high-temperature-resistant disc spring is a bimetallic compensation spring which can compensate the influence of temperature on the stiffness of the spring.

5. A wafer level package reflow soldering anti-warping self-adapting reinforcement device according to claim 1, wherein, The grid type pressing mechanism (4) comprises horizontal pressing rods (41), vertical pressing rods (42) and tail wing pressing rods (43); two spaced horizontal pressing rods (41) and two spaced vertical pressing rods (42) are orthogonally clamped, and four tail wing pressing rods (43) are clamped at the ends of the horizontal pressing rods (41) and the vertical pressing rods (42), respectively, and the grid type pressing structure of multiple grids is formed by the cross arrangement between the horizontal pressing rods (41), the vertical pressing rods (42) and the tail wing pressing rods (43).

6. A wafer level package reflow soldering anti-warping self-adapting reinforcement device according to claim 5, characterized in that, It also includes a flexible gasket arranged at the bottom of the horizontal pressing rods (41), the vertical pressing rods (42) and the tail wing pressing rods (43), which is made of a high-temperature-resistant, low-modulus and high-elasticity Mylar; the horizontal pressing rods (41), the vertical pressing rods (42) and the tail wing pressing rods (43) are made of a high-strength, low-thermal expansion coefficient and high-temperature-resistant ceramic matrix composite material.

7. A wafer level package reflow soldering anti-warping self-adapting reinforcement device according to claim 5, characterized in that, The U-shaped pressing groove (44) and the through hole (45) are also included, a plurality of the U-shaped pressing grooves (44) are linearly arranged on each of the transverse pressing rod (41), the longitudinal pressing rod (42) and the tail wing pressing rod (43), the through hole (45) is arranged on the U-shaped pressing groove (44), the transverse pressing rod (41), the longitudinal pressing rod (42) and the tail wing pressing rod (43) are clamped and locked by the U-shaped pressing groove (44) and the through hole (45); meanwhile, the size of the multiple grid apertures of the grid pressing structure is flexibly adjusted according to the area required by the to-be-welded components (22) on the to-be-reflow-welded wafer-level substrate assembly (2).

8. A wafer level package reflow soldering anti-warping self-adapting reinforcement device according to claim 7, characterized in that, The fixed screw one (46), the fixed screw two (47) and the fixed screw three (48) with self-locking structures are also included; the fixed screw one (46) is used for being sequentially inserted into the through hole (45) on the U-shaped pressing groove (44) between the transverse pressing rod (41) and the longitudinal pressing rod (42) from the bottom of the substrate (21) and the preset hole of the substrate (21), and the end locking nut (461) of the fixed screw one (46) is locked, so as to pre-tighten the transverse pressing rod (41), the longitudinal pressing rod (42) and the substrate (21); meanwhile, the elastic washer (462) is sleeved between the fixed screw one (46) and the longitudinal pressing rod (42); the fixed screw two (47) is used for being sequentially inserted into the through hole (45) on the U-shaped pressing groove (44) between the tail wing pressing rod (43) and the transverse pressing rod (41) from the top, the preset hole of the substrate (21) and the locking screw hole of the support platform (1), and the through hole (45) on the U-shaped pressing groove (44) between the tail wing pressing rod (43) and the longitudinal pressing rod (42), the preset hole of the substrate (21) and the locking screw hole of the support platform (1), so as to pre-tighten the transverse pressing rod (41), the tail wing pressing rod (43) and the substrate (21), and the longitudinal pressing rod (42), the tail wing pressing rod (43) and the substrate (21); the end of the transverse pressing rod (41), the longitudinal pressing rod (42) and the tail wing pressing rod (43) and the locking screw hole of the support platform (1) are pre-tightened by the fixed screw three (48).

9. A wafer level package reflow soldering anti-warping self-adapting reinforcement device according to claim 8, characterized in that, Also include the compression force exerting mechanism, the compression force exerting mechanism adopts the fastening tool driven by servo motor, is used for exerting the pre-tightening action to the fixed screw one (46), the fixed screw two (47) and the fixed screw three (48);The servo motor driven fastening tool also includes the force value measuring sensor configured simultaneously, is used for determining whether the fastening force reaches the preset threshold;Also include the limit block, multiple limit blocks are respectively arranged on the substrate (21), are used for with the end bottom of the transverse compression rod (41) and the longitudinal compression rod (42) abut, to prevent the fastening force from being too large to cause damage to the wafer level substrate (21).

10. A reinforcing method of a warpage-preventing self-adapting reinforcing device for wafer level package reflow soldering, using the warpage-preventing self-adapting reinforcing device for wafer level package reflow soldering according to any one of claims 1 to 9, characterized in that, Including: Place the components to be welded in the corresponding area of the wafer level substrate; Install the floating spring support mechanism on the support platform, and press the wafer level substrate on the grid type compression mechanism by the compression force exerting mechanism; Place the grid type compression mechanism with the wafer level substrate on the support platform, and apply pre-tightening force to complete the pre-tightening with the support platform through the compression force exerting mechanism; Compress the high-temperature resistant disc spring to a certain working stroke, so that the bottom surface of the grid type compression mechanism uniformly contacts the substrate surface, to ensure the flatness constraint in the initial state.

Images