An adaptive levelling device

Abstract

The application relates to the technical field of semiconductor thermal compression bonding, and particularly relates to a self-adaptive leveling device which mainly solves the technical problem that chips and substrates cannot be uniformly attached in a thermal compression bonding process. The self-adaptive leveling device comprises a base seat, a leveling piece, a magnet and a limiting mechanism, the bottom surface of the base seat is provided with a ball groove, a porous air-permeable spherical seat with a spherical socket-shaped bottom surface is installed in the ball groove, a center hole is arranged at the center of the porous air-permeable spherical seat, the magnet is installed in the ball groove through the center hole, the top end part of the leveling piece is spherical and is adapted to the porous air-permeable spherical seat, the base seat is provided with a positive pressure air channel opening and a negative pressure air channel opening, and the limiting mechanism is used for limiting the circumferential rotation of the leveling piece around the vertical shaft. The self-adaptive leveling device has compact structure and high universality, is not only suitable for the leveling of chips and substrates in the thermal compression bonding process, but also can be applied to other scenes requiring high-precision leveling, and has wide application range.

Description

Technical Field

[0001] This invention relates to the field of semiconductor thermo-press bonding technology, specifically to an adaptive leveling device. Background Technology

[0002] Thermocompression bonding, an advanced packaging technology, achieves material bonding by simultaneously applying heat and pressure. Its core principle is to use thermal energy to induce atomic diffusion on the surface of metal bumps, which, combined with mechanical pressure, forms atomic-level bonds, thereby establishing stable electrical and mechanical connections. Currently, thermocompression bonding technology is mainly used in advanced packaging processes such as 2.5D packaging, 3D packaging, high-bandwidth memory, chip chips, image sensors, and fine-pitch, high-density interconnects.

[0003] A thermosetting bonding head comprises, from top to bottom, a driving component, a heating assembly for heating the chip, and a fixture for adsorbing the chip. During thermosetting, the thermosetting bonding head must press the heated chip onto the substrate, which places extremely high demands on the parallelism of the contact surfaces. However, due to limitations in chip manufacturing processes, differences in the coefficients of thermal expansion of materials, and machining accuracy errors of the fixture, the chip and substrate often exhibit microscopic warping or relative tilting under high-temperature conditions. If the thermosetting bonding head lacks effective self-adjusting capabilities, rigid pressing will result in uneven adhesion between the chip and the substrate, causing excessive local pressure that damages bumps or the chip, or insufficient pressure that leads to defects such as poor soldering and voids, severely reducing the interconnect yield and long-term reliability of the device.

[0004] Existing technologies for leveling devices between two components mostly rely on rigid connections or simple passive elastic devices, which are difficult to accurately compensate for the complex dynamic warping between the chip and the substrate at the micron-scale required by thermo-press bonding processes. Summary of the Invention

[0005] In order to solve the technical problem that the chip and the substrate cannot be uniformly bonded in the hot-press bonding process, the present invention provides an adaptive leveling device.

[0006] This invention is achieved using the following technical solution:

[0007] An adaptive leveling device includes a base, a leveling component, a magnet for adsorbing the leveling component, and a limiting mechanism. The base has a spherical groove on its bottom surface, and a porous, permeable spherical surface seat with a spherical bottom is installed in the groove. The porous, permeable spherical surface seat has a central hole, through which the magnet is installed in the groove. The top of the leveling component is spherical and fits into the porous, permeable spherical surface seat to form a spherical mating pair. The base has a positive pressure air inlet and a negative pressure air inlet. Compressed air introduced through the positive pressure air inlet is evenly output through the porous, permeable spherical surface seat, forming a uniform air film between the porous, permeable spherical surface seat and the leveling component. Negative pressure gas is introduced through the negative pressure air inlet and evenly drawn out through the porous, permeable spherical surface seat, thus locking the leveling component under negative pressure to the porous, permeable spherical surface seat. The limiting mechanism is used to restrict the circumferential rotation of the leveling component.

[0008] When aligning the chip and substrate using the adaptive leveling device described above, the adaptive leveling device is installed between the drive assembly and heating assembly of the thermosetting bonding head. The chip is adsorbed onto the heating assembly. Then, compressed air is introduced through the positive pressure air inlet. The compressed air is evenly output through the porous permeable spherical surface seat, forming a uniform air film between the porous permeable spherical surface seat and the leveling component. At this time, the leveling component is only subject to a weak pre-tightening adsorption force provided by the magnet. The air film eliminates the mechanical frictional resistance between the spherical mating pairs, allowing the leveling component to automatically adjust its angle according to the bonding surface of the chip and the substrate, achieving unconstrained adaptive leveling. Simultaneously, the limiting mechanism... The circumferential rotation of the leveling component around the vertical axis is restricted to prevent deflection during adjustment. After leveling, the positive pressure air inlet is closed and the negative pressure air inlet is opened. Gas is evenly drawn through the porous spherical surface seat, evacuating the air film between the porous spherical surface seat and the leveling component, forming a uniform vacuum adsorption force. With the assistance of magnets, the leveling component is rigidly locked onto the porous spherical surface seat, and the posture of the spherical mating pair is completely fixed, ensuring stable and non-offset leveling accuracy in subsequent processes, thereby achieving the leveling of the chip and the substrate. In addition, this adaptive leveling device can also be used for leveling between two components in other fields, with a wide range of applications.

[0009] Furthermore, the limiting mechanism includes an annular component and two limiting plates. The annular component is movably fitted onto the bottom end of the leveling component. The top surface of the annular component has first limiting notches on both the left and right sides. One end of each of the two limiting plates is fixed to the left and right sides of the base, respectively. The inner side of the other end of each of the two limiting plates is fixed with a first limiting post that matches the first limiting notch. The depth of the first limiting notch in the height direction is greater than the diameter of the first limiting post. The top surface of the annular component has second limiting notches on both the front and rear sides. The bottom end of the leveling component is cylindrical, and two second limiting posts that match the two second limiting notches are provided on the circumferential surface of the bottom end of the leveling component. The depth of the second limiting notch in the height direction is greater than the diameter of the second limiting post, thereby restricting the leveling component from rotating circumferentially around the vertical axis.

[0010] Furthermore, the limiting mechanism also includes a clamping plate, which is fixed to the bottom end of the leveling component, and the edge of the top surface of the clamping plate blocks the bottom end surface of the annular component. The other ends of both limiting plates are also fixed with locking bolts for securing the clamping plates during transport. During transport, the negative pressure air inlet is blocked, and the leveling component cannot be effectively fixed by magnets alone. Also, since the annular component lacks a fixed structure, it can only be disassembled and cannot be transported as a whole. Therefore, clamping plates are added to fix the annular component and the leveling component, facilitating transport.

[0011] Furthermore, the bottom end face of the ring-shaped part is evenly distributed with multiple mounting notches in the circumferential direction. Each mounting notch is provided with a spring arranged axially in the vertical direction between itself and the top surface of the clamping plate, which improves the stability during leveling.

[0012] Furthermore, the base has a square cross-section and is provided with fixing holes at all four corners, which facilitates the fixing of the base to the drive assembly of the thermo-press bonding head through the fixing holes and fixing bolts.

[0013] Furthermore, the porous spherical bulb seat is fixed inside the spherical groove with epoxy resin adhesive, which facilitates the fixation of the porous spherical bulb seat.

[0014] Furthermore, the magnet is fixed inside the ball groove with epoxy resin glue, which facilitates the fixation of the magnet.

[0015] Furthermore, the clamp plate is fixed to the bottom surface of the leveling component by multiple screws, making the fixing structure simple and easy to implement.

[0016] The beneficial effects of this invention are as follows: 1) This invention uses a spherical mating pair and a combination of positive and negative pressure air inlets, enabling the leveling component to achieve adaptive deflection, resulting in high leveling efficiency and good parallelism accuracy, effectively avoiding the problem of uneven bonding between the chip and the substrate in the thermoforming process; 2) The adaptive leveling device of this invention achieves leveling suspension and negative pressure locking by switching between positive and negative pressure air inlets. When locking under negative pressure, the negative pressure gas is evenly drawn through the porous spherical seat, ensuring reliable locking without local stress concentration and guaranteeing stable leveling posture; 3) The adaptive leveling device of this invention has a compact structure and strong versatility. It is not only suitable for leveling the chip and substrate in the thermoforming process, but also for other scenarios requiring high-precision leveling, making it widely applicable. Attached Figure Description

[0017] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the overall structure of the adaptive leveling device described in this invention;

[0020] Figure 2 This is a schematic diagram of the leveling component.

[0021] Figure 3 This is a schematic diagram of the assembly structure of the base, the porous spherical surface seat, the magnet, and the two limiting plates.

[0022] Figure 4 This is a schematic diagram of the ring-shaped component.

[0023] In the diagram: 1-Base, 2-Magnet, 3-Leveling component, 4-Porous permeable balloon surface seat, 5-Positive pressure air inlet, 6-Negative pressure air inlet, 7-Annular component, 8-Limiting plate, 9-First limiting notch, 10-First limiting post, 11-Second limiting notch, 12-Second limiting post, 13-Clamping plate, 14-Locking bolt, 15-Mounting notch, 16-Spring, 17-Fixing hole. Detailed Implementation

[0024] To better understand the above-mentioned objectives, features, and advantages of the present invention, the solutions of the present invention will be further described below. It should be noted that, unless otherwise specified, the embodiments of the present invention and the features thereof can be combined with each other.

[0025] Many specific details are set forth in the following description in order to provide a full understanding of the invention, but the invention may also be practiced in other ways different from those described herein; obviously, the embodiments in the specification are only some embodiments of the invention, and not all embodiments.

[0026] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0027] like Figure 1 , 2As shown in Figures 3 and 4, an adaptive leveling device includes a base 1, a leveling component 3, a magnet 2 for adsorbing the leveling component 3, and a limiting mechanism. The bottom surface of the base 1 is provided with a spherical groove, and a porous permeable spherical surface seat 4 with a spherical bottom is installed in the spherical groove. The porous permeable spherical surface seat 4 has a central hole in its center, and the magnet 2 is installed in the spherical groove through the central hole. The top end of the leveling component 3 is spherical and fits into the porous permeable spherical surface seat 4 to form a spherical mating pair. The base 1 is provided with a positive pressure air inlet 5 and a negative pressure air inlet 6. Compressed air introduced through the positive pressure air inlet 5 is evenly output through the porous permeable spherical surface seat 4 and forms a uniform air film between the porous permeable spherical surface seat 4 and the leveling component 3. Negative pressure gas is introduced through the negative pressure air inlet 6 and the gas is evenly drawn out through the porous permeable spherical surface seat 4 to realize the negative pressure locking of the leveling component 3 to the porous permeable spherical surface seat 4. The limiting mechanism is used to restrict the circumferential rotation of the leveling component 3.

[0028] When aligning the chip and substrate using the adaptive leveling device described above, the adaptive leveling device is installed between the driving component and the heating component of the thermosetting bonding head. The chip is adsorbed onto the heating component. Then, compressed air is introduced into the positive pressure air inlet 5. The compressed air is evenly output through the porous permeable spherical surface seat 4, forming a uniform air film between the porous permeable spherical surface seat 4 and the leveling component 3. At this time, the leveling component 3 is only subject to the weak pre-tightening adsorption force provided by the magnet 2. The air film eliminates the mechanical frictional resistance between the spherical mating pairs, allowing the leveling component 3 to automatically adjust its angle according to the bonding surface of the chip and the substrate, achieving unconstrained adaptive leveling. At the same time, the limiting mechanism limits... The leveling component rotates circumferentially around the vertical axis to prevent deflection during adjustment. After leveling, the positive pressure air inlet 5 is closed and the negative pressure air inlet 6 is opened. Gas is evenly drawn through the porous permeable spherical seat 4, evacuating the air film between the porous permeable spherical seat 4 and the leveling component 5, forming a uniform vacuum adsorption force. With the assistance of the magnet 2, the leveling component 3 is rigidly locked onto the porous permeable spherical seat 4, and the posture of the spherical mating pair is completely fixed, ensuring stable leveling accuracy and no deviation in subsequent processes, thereby achieving the leveling of the chip and the substrate. In addition, this adaptive leveling device can also be used for leveling between two components in other fields, with a wide range of applications.

[0029] In specific implementation, the limiting mechanism includes an annular component 7 and two limiting plates 8. The annular component 7 is movably fitted onto the bottom end of the leveling component 3. The top surface of the annular component 7 has first limiting notches 9 on both the left and right sides. One end of each of the two limiting plates 8 is fixed to the left and right sides of the base 1. The inner side of the other end of each of the two limiting plates 8 is fixed with a first limiting post 10 that matches the first limiting notch 9. The depth of the first limiting notch 9 in the height direction is greater than the diameter of the first limiting post 10. The top surface of the annular component 7 has second limiting notches 11 on both the front and rear sides. The bottom end of the leveling component 3 is cylindrical, and the circumferential surface of the bottom end of the leveling component 3 has two second limiting posts 12 that match the two second limiting notches 11 respectively. The depth of the second limiting notches 11 in the height direction is greater than the diameter of the second limiting posts 12, thereby restricting the leveling component 3 from rotating circumferentially around the vertical axis.

[0030] In specific implementation, the limiting mechanism also includes a clamping plate 13, which is fixed to the bottom end of the leveling component 3 and the edge of the top surface of the clamping plate 13 blocks the bottom surface of the annular component 7. The other ends of both limiting plates 8 are also fixed with locking bolts 14 for locking the clamping plates 13 during transport. During transport, the negative pressure air inlet 6 is not open, and the leveling component 3 cannot be effectively fixed by the magnet 2 alone. Furthermore, since the annular component 7 has no fixed structure, it can only be disassembled and cannot be transported as a whole. Therefore, the clamping plate 13 is added to fix the annular component 7 and the leveling component 3, facilitating transport.

[0031] In practice, the bottom end face of the ring part 7 is evenly distributed with multiple mounting notches 15. Each mounting notch 15 is provided with a spring 16 arranged axially in the vertical direction between it and the top surface of the clamp plate 13, which improves the stability during leveling.

[0032] In this specific embodiment, the cross-section of the base 1 is square and the four corners of the base 1 are provided with fixing holes 17, so that the base 1 can be fixed to the drive assembly of the thermo-press bonding head through the fixing holes 17 and fixing bolts.

[0033] In this specific embodiment, the porous spherical surface holder 4 is fixed in the spherical groove with epoxy resin glue, which facilitates the fixation of the porous spherical surface holder 4.

[0034] In this specific embodiment, the magnet 2 is fixed in the ball groove with epoxy resin glue, which facilitates the fixation of the magnet 2.

[0035] In this specific embodiment, the clamp plate 13 is fixed to the bottom surface of the leveling component 3 by multiple screws, and the fixing structure is simple and easy to implement.

[0036] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the present invention. Although detailed descriptions have been provided with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments, and all should be covered by the protection scope of the claims.

Claims

1. An adaptive leveling device, characterized in that, The system includes a base (1), a leveling component (3), a magnet (2) for adsorbing the leveling component (3), and a limiting mechanism. The bottom surface of the base (1) is provided with a ball groove, and a porous, permeable spherical surface seat (4) with a spherical bottom is installed in the ball groove. The center of the porous, permeable spherical surface seat (4) is provided with a central hole, and the magnet (2) is installed in the ball groove through the central hole. The top part of the leveling component (3) is spherical and fits into the porous, permeable spherical surface seat (4) to form a spherical mating pair. The base (1) is provided with There are positive pressure air inlets (5) and negative pressure air inlets (6). Compressed air introduced through the positive pressure air inlet (5) is evenly output through the porous permeable air vent seat (4) and forms a uniform air film between the porous permeable air vent seat (4) and the leveling component (3). Negative pressure gas is introduced through the negative pressure air inlet (6) and the gas is evenly drawn through the porous permeable air vent seat (4) to achieve negative pressure locking of the leveling component (3) to the porous permeable air vent seat (4). The limiting mechanism is used to limit the circumferential rotation of the leveling component (3).

2. The adaptive leveling device according to claim 1, characterized in that, The limiting mechanism includes a ring (7) and two limiting plates (8). The ring (7) is movably fitted onto the bottom end of the leveling part (3). The top surface of the ring (7) is provided with first limiting notches (9) on both the left and right sides. One end of the two limiting plates (8) is fixed to the left and right sides of the base (1). The inner side of the other end of the two limiting plates (8) is fixed with a first limiting post (10) that matches the first limiting notch (9). The depth of the first limiting notch (9) in the height direction is greater than the diameter of the first limiting post (10). The top surface of the ring (7) is provided with second limiting notches (11) on both the front and back sides. The bottom end of the leveling part (3) is cylindrical and two second limiting posts (12) that match the two second limiting notches (11) are provided on the circumferential surface of the bottom end of the leveling part (3). The depth of the second limiting notch (11) in the height direction is greater than the diameter of the second limiting post (12).

3. The adaptive leveling device according to claim 2, characterized in that, The limiting mechanism also includes a clamp plate (13), which is fixed to the bottom end of the leveling component (3) and the edge of the top surface of the clamp plate (13) blocks the bottom end of the ring component (7). The other ends of the two limiting plates (8) are also fixed with locking bolts (14) for locking the clamp plate (13) during transport.

4. The adaptive leveling device according to claim 3, characterized in that, The bottom end face of the ring part (7) is evenly distributed with multiple mounting notches (15), and each mounting notch (15) is provided with a spring (16) arranged axially in the vertical direction between the top surface of the clamp plate (13).

5. The adaptive leveling device according to claim 4, characterized in that, The cross-section of the base (1) is square and the four corners of the base (1) are provided with fixing holes (17).

6. The adaptive leveling device according to claim 5, characterized in that, The porous spherical surface seat (4) is fixed to the spherical groove with epoxy resin glue.

7. The adaptive leveling device according to claim 6, characterized in that, The magnet (2) is fixed in the ball groove by epoxy resin glue.

8. The adaptive leveling device according to claim 7, characterized in that, The clamp plate (13) is fixed to the bottom end face of the leveling component (3) by multiple screws.

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