Wafer bonding machine

Abstract

The utility model provides a wafer bonding machine, relates to the technical field of semiconductor processing equipment, and is designed for solving the problem that the existing wafer bonding machine uses an electric cylinder or a hydraulic cylinder to provide a pressing force, and the pressing force is applied to a wafer pair at one time, so that the pressing precision is low. Comprising a vacuum cavity, a pressure applying device located outside the vacuum cavity and a pressure head located inside the vacuum cavity, the pressure applying device comprises a pressure driving mechanism, a pressure applying shaft, a pressure applying cavity and a reset element, the pressure driving mechanism is connected with the pressure applying shaft, the pressure applying shaft movably penetrates through the pressure applying cavity in the pressure applying direction, and the pressure applying shaft is provided with a piston boss; the pressurizing cavity is provided with an air inlet used for allowing air flow to enter and act on the piston boss and an air outlet used for allowing the air flow to be discharged, and the reset element is configured to enable the pressurizing shaft to have the trend of moving towards the pressure reduction direction all the time; the pressing head comprises a first pressing disc and a second pressing disc, the first pressing disc is installed on the pressurizing shaft, and the second pressing disc is installed in the vacuum cavity. The press-fit device is high in press-fit precision.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of semiconductor processing equipment, specifically relates to a wafer bonder. BACKGROUND

[0002] The pressing device is the core unit of the wafer bonder, and the pressure control precision and the pressure uniformity are key indexes affecting the bonding effect. The main function of the pressing device is to complete the pressing of the positioned upper and lower wafers in the wafer bonding process, and after pressing, the van der Waals force on the wafer surface is used to realize the bonding of the two wafers. The wafer specifications of the current bonding process are 8 inches, 6 inches and 4 inches, etc. According to different wafer specifications, the maximum process pressure used is as high as 100KN.

[0003] At present, the wafer bonder used to meet the above process pressure often uses an electric cylinder or a hydraulic cylinder to provide the pressing force, and the pressing force is applied to the wafer pair at one time, resulting in low pressing precision, and there is a risk of oil leakage during use, which pollutes the dust-free environment. UTILITY MODEL CONTENTS

[0004] The utility model aims at providing a wafer bonder to solve the technical problem that the existing wafer bonder uses an electric cylinder or a hydraulic cylinder to provide the pressing force, and the pressing force is applied to the wafer pair at one time, resulting in low pressing precision.

[0005] The wafer bonder provided by the utility model comprises a vacuum cavity, a pressing device located outside the vacuum cavity and a pressure head located inside the vacuum cavity, the pressing device comprises a pressure driving mechanism, a pressure shaft, a pressure cavity and a reset element, the pressure driving mechanism is connected with the pressure shaft, the pressure shaft is movably penetrated through the pressure cavity along a pressure direction, and the pressure shaft is provided with a piston boss; the pressure cavity is provided with an air inlet for making airflow enter and act on the piston boss and an air outlet for making airflow discharge, the reset element is configured to make the pressure shaft always have a tendency to move in a pressure reduction direction; and the pressure head comprises a first pressure disc and a second pressure disc, the first pressure disc is installed on the pressure shaft, and the second pressure disc is installed on the vacuum cavity.

[0006] Further, the reset element comprises a bellows, the bellows is located inside the pressure cavity and sleeved on the pressure shaft, a first end of the bellows is in sealing connection with the pressure cavity, a second end of the bellows is in sealing connection with the piston boss, and the inner cavity of the bellows is in communication with the air inlet and the air outlet.

[0007] Further, the pressurizing cavity comprises a top plate, a support ring and a bottom plate, the bottom plate is fixedly arranged opposite to the vacuum cavity, the support ring is fixedly connected to the bottom plate, and the top plate is fixedly connected to the support ring, wherein the air inlet and the air outlet are both arranged on the top plate, and the first end of the bellows is sealingly connected to the top plate; the top plate is provided with a top through hole, the bottom plate is provided with a bottom through hole, the pressurizing shaft is arranged in the top through hole and the bottom through hole, and a sealing structure is arranged between the pressurizing shaft and the hole wall of the bottom through hole.

[0008] Further, the wafer bonding machine further comprises a pressure sensor, the pressure sensor is installed between the pressurizing shaft and the first pressure plate, and the pressure sensor is used for sensing the pressure received by the pressurizing shaft.

[0009] Further, the wafer bonding machine further comprises a leveling mechanism, the leveling mechanism is arranged between the pressure sensor and the first pressure plate, and the leveling mechanism is used for adjusting the parallelism of the first pressure plate.

[0010] Further, the pressure applying device further comprises a mounting seat, the mounting seat is fixedly connected to the pressurizing cavity, and the pressure driving mechanism is movably arranged in the mounting seat in the pressurizing direction; a guide structure is arranged between the pressure driving mechanism and the mounting seat, and the guide structure is used for guiding the movement of the pressure driving mechanism.

[0011] Further, the pressure applying device further comprises a direction feedback unit, the direction feedback unit is arranged in the mounting seat, and the direction feedback unit is used for monitoring the movement direction of the pressurizing shaft.

[0012] Further, the air inlet is provided with an air inlet control device, the air inlet control device is used for controlling the air inlet flow of the air inlet; and the air outlet is provided with an air outlet control device, the air outlet control device is used for controlling the air outlet flow of the air outlet.

[0013] Further, the first pressure plate comprises an upper cold plate, an upper heating plate and an upper pressure plate arranged in sequence from top to bottom, wherein the upper cold plate and the upper heating plate can approach or move away from each other; and the second pressure plate comprises a lower pressure plate, a lower heating plate and a lower cold plate arranged in sequence from top to bottom, wherein the lower cold plate and the lower heating plate can approach or move away from each other.

[0014] Further, the upper cold plate and the lower cold plate are both provided with cooling flow channels configured to circulate cooling fluid.

[0015] The wafer bonding machine brings the beneficial effects that:

[0016] When a wafer pair needs to be bonded, the wafer pair is placed between the first pressing plate and the second pressing plate, the pressure driving mechanism is used to drive the pressing shaft to move along the pressing direction, so that the first pressing plate is quickly moved to a position close to the wafer pair and is kept at the position; then, the gas flow is introduced from the gas inlet and acts on the piston boss of the pressing shaft, so that the pressing shaft continues to move along the pressing direction, and since the gas flow is gradually applied to the piston boss during the process, the pressing shaft will slowly move until the first pressing plate contacts the wafer pair and exerts pressure on the wafer pair to complete the bonding process.

[0017] Therefore, the wafer bonding machine divides the displacement of the first pressing plate into two sections, first moves the first pressing plate to a position close to the wafer pair quickly through the pressure driving mechanism to improve efficiency, and then slowly moves the first pressing plate to apply pressure to the wafer pair through the action of the gas flow on the pressing shaft to improve accuracy, effectively improving the problem of low accuracy caused by the fact that the pressing force is applied to the wafer pair at one time in the prior art.

[0018] In addition, by externally arranging the pressing device, the pressing device is located outside the vacuum cavity, and pollution to the vacuum cavity is reduced, thereby achieving dustproof protection effect on the wafer pair. BRIEF DESCRIPTION OF DRAWINGS

[0019] In order to more clearly illustrate the technical scheme in the embodiments of the present application or the prior art, the drawings needed in the following embodiment or prior art description will be briefly introduced. Obviously, the drawings in the following description are only embodiments of the present application, and those skilled in the art can obtain other drawings according to the provided drawings without creative labor.

[0020] Figure 1 The structure diagram of the wafer bonding machine provided by the embodiment of the present application is shown in the figure.

[0021] Figure 2 The longitudinal sectional view of the wafer bonding machine provided by the embodiment of the present application is shown in the figure.

[0022] Figure 3 The longitudinal sectional view of the pressing device of the wafer bonding machine provided by the embodiment of the present application is shown in the figure.

[0023] Figure 4 The structure diagram of the pressing head of the wafer bonding machine provided by the embodiment of the present application is shown in the figure.

[0024] Figure 5 The local structure longitudinal sectional view of the pressing device of the wafer bonding machine provided by the embodiment of the present application is shown in the figure.

[0025] Explanation of reference signs:

[0026] 100 - vacuum cavity; 200 - pressure applying device; 300 - pressure head; 400 - pressure sensor; 500 - leveling mechanism;

[0027] 210 - pressure driving mechanism; 220 - pressure applying shaft; 230 - pressure applying cavity; 240 - reset element; 250 - mounting seat; 260 - guiding structure; 270 - direction feedback unit;

[0028] 221 - piston boss;

[0029] 231 - top plate; 2311 - air inlet; 2312 - air outlet; 2313 - top through hole; 232 - support ring; 233 - bottom plate; 2331 - bottom through hole; 234 - sealing structure; 235 - sealing ring;

[0030] 310 - first pressure disc; 320 - second pressure disc;

[0031] 311 - upper cold disc; 312 - upper heating disc; 313 - upper pressure disc;

[0032] 321 - lower cold disc; 322 - lower heating disc; 323 - lower pressure disc. DETAILED DESCRIPTION

[0033] In order to make the above-mentioned purpose, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application will be described in detail below with reference to the drawings. It should be understood that the specific embodiments described herein are only used to explain the present application and do not limit the present application.

[0034] Figure 1 The structure schematic diagram of the wafer bonding machine provided by the present embodiment is shown in the figure; Figure 2 The longitudinal sectional view of the wafer bonding machine provided by the present embodiment is shown in the figure. Figure 1 and Figure 2As shown, the embodiment provides a wafer bonding machine, comprising a vacuum cavity 100, a pressing device 200 located outside the vacuum cavity 100, and a pressure head 300 located inside the vacuum cavity 100, wherein the pressing device 200 comprises a pressure driving mechanism 210, a pressing shaft 220, a pressing cavity 230, and a reset element 240, specifically, the pressure driving mechanism 210 is connected with the pressing shaft 220, the pressing shaft 220 is movably penetrated through the pressing cavity 230 along a pressing direction, and the pressing shaft 220 is provided with a piston boss 221; the pressing cavity 230 is provided with an air inlet 2311 for making airflow enter and act on the piston boss 221, and an air outlet 2312 for making airflow exhaust, and the reset element 240 is configured to make the pressing shaft 220 always have a tendency to move in a pressure reducing direction; the pressure head 300 comprises a first pressure plate 310 and a second pressure plate 320, the first pressure plate 310 is installed on the pressing shaft 220, and the second pressure plate 320 is installed on the vacuum cavity 100.

[0035] When it is needed to perform a bonding process on a wafer pair, the wafer pair can be placed between the first pressure plate 310 and the second pressure plate 320, the pressure driving mechanism 210 is used to drive the pressing shaft 220 to move along the pressing direction, so that the first pressure plate 310 is quickly moved to a position close to the wafer pair, and the first pressure plate 310 is kept at the position; then, the airflow is made to enter from the air inlet 2311 and act on the piston boss 221 of the pressing shaft 220, so that the pressing shaft 220 continues to move along the pressing direction, because the airflow is gradually acting on the piston boss 221 in the process, the pressing shaft 220 will slowly move, until the first pressure plate 310 contacts the wafer pair and exerts pressure on the wafer pair, to complete the bonding process.

[0036] Therefore, the wafer bonding machine divides the displacement of the first pressure plate 310 into two sections by the above-mentioned arrangement, first, the pressure driving mechanism 210 is used to quickly move the first pressure plate 310 to a position close to the wafer pair, to improve efficiency, and then the airflow is used to slowly move the first pressure plate 310 to exert pressure on the wafer pair, to improve precision, which effectively improves the problem of low precision caused by the pressing force being applied to the wafer pair at one time in the prior art.

[0037] In addition, by externally arranging the pressing device 200, the pressing device 200 is located outside the vacuum cavity 100, which also reduces the pollution caused to the vacuum cavity 100, thereby achieving a dustproof protection effect on the wafer pair.

[0038] In the embodiment, the pressure driving mechanism 210 can be a hydraulic cylinder.

[0039] It should be noted that the above-mentioned "pressing direction" can be represented by the direction indicated by the arrow a in Figure 2 , and the above-mentioned "pressure reducing direction" can be represented by the direction indicated by the arrow b in Figure 2indicated by the arrow b in the figure, wherein the pressurizing direction is opposite to the depressurizing direction.

[0040] Figure 3 A longitudinal sectional view of the pressing device 200 of the wafer bonding machine provided in the embodiment is shown. Please continue to refer to Figure 2 , and combine with Figure 3 In the embodiment, the reset element 240 can include a bellows, wherein the bellows is located inside the pressurizing cavity 230 and sleeved on the pressurizing shaft 220, the first end of the bellows is in sealing connection with the pressurizing cavity 230, the second end of the bellows is in sealing connection with the piston boss 221, and the inner cavity of the bellows is in communication with the gas inlet 2311 and the gas outlet 2312.

[0041] When the gas flow enters from the gas inlet 2311, it will enter the inner cavity of the bellows, and under the action of the gas flow pressure, the bellows will be elongated, thereby driving the pressurizing shaft 220 in sealing connection therewith to move in the pressurizing direction, so as to realize the bonding of the wafer pair; after the bonding process is completed, the gas flow in the inner cavity of the bellows can be discharged through the gas outlet 2312, and with the gradual decrease of the pressure in the inner cavity of the bellows, the bellows will be shortened and reset under the action of its own structure, thereby driving the pressurizing shaft 220 to move in the depressurizing direction.

[0042] By setting the reset element 240 as a bellows, on the one hand, the structural deformation characteristics of the bellows can be utilized to achieve the purpose of resetting the pressurizing shaft 220, and on the other hand, the inner cavity of the bellows can form a gas inlet channel from the gas inlet 2311 to the piston boss 221 and a gas outlet channel from the piston boss 221 to the gas outlet 2312, so as to ensure the movement reliability of the pressurizing shaft 220.

[0043] Please continue to refer to Figure 2 and Figure 3 In the embodiment, the pressurizing cavity 230 can include a top plate 231, a support ring 232 and a bottom plate 233, specifically, the bottom plate 233 is fixedly arranged opposite to the vacuum cavity 100, the support ring 232 is fixedly connected to the bottom plate 233, and the top plate 231 is fixedly connected to the support ring 232, wherein the gas inlet 2311 and the gas outlet 2312 are both formed in the top plate 231, and one end of the bellows is in sealing connection with the top plate 231; the top plate 231 is provided with a top through hole 2313, the bottom plate 233 is provided with a bottom through hole 2331, the pressurizing shaft 220 is arranged through the top through hole 2313 and the bottom through hole 2331, and a sealing structure 234 is arranged between the pressurizing shaft 220 and the hole wall of the bottom through hole 2331.

[0044] The structure of the pressurizing cavity 230 ensures its structural stability. By opening the air inlet 2311 and the air outlet 2312 on the top plate 231, the air flow can enter the inner cavity of the bellows through the top of the bellows, without the need to additionally open holes on the side wall of the bellows, thereby reducing the manufacturing cost.

[0045] It should be noted that, in the present embodiment, the lower part of the pressurizing shaft 220 is sealed from the bottom through hole 2331 by the sealing structure 234, so that there is no air flow leakage between the pressurizing shaft 220 and the bottom through hole 2331 during the up-and-down movement of the pressurizing shaft 220. The upper part of the pressurizing shaft 220 is provided with a sealing boss, and a sealing ring 235 is arranged between the sealing boss and the top plate 231 to ensure the sealing of the top through hole 2313. The sealing ring 235 is in a compressed state, so that the sealing ring 235 and the top plate 231 do not separate even when the pressurizing shaft 220 moves in the pressurizing direction for bonding. That is, the displacement of the pressurizing shaft 220 in the pressurizing direction is always within the reset length of the sealing ring 235, so as to prevent air flow leakage between the pressurizing shaft 220 and the top through hole 2313.

[0046] Please continue to refer to Figure 1 and Figure 2 In the present embodiment, the wafer bonding machine can further include a pressure sensor 400, wherein the pressure sensor 400 is installed between the pressurizing shaft 220 and the first pressure plate 310, and the pressure sensor 400 is used to sense the pressure received by the pressurizing shaft 220.

[0047] When the bonding process is performed, the pressurizing shaft 220 applies pressure to the wafer pair. During this process, the pressurizing shaft 220 receives a reaction force, and the pressure sensor 400 senses the reaction force to timely remind or stop the pressurizing shaft 220 from continuing to move in the pressurizing direction when the pressure is too large, so as to protect the wafer pair and improve the bonding precision.

[0048] Please continue to refer to Figure 1 and Figure 2 In the present embodiment, the wafer bonding machine can further include a leveling mechanism 500, wherein the leveling mechanism 500 is arranged between the pressure sensor 400 and the first pressure plate 310, and the leveling mechanism 500 is used to adjust the parallelism of the first pressure plate 310.

[0049] The arrangement of the above-mentioned leveling mechanism 500 enables the first pressure plate 310 to maintain a posture parallel to the horizontal plane during the movement of the first pressure plate 310 in the pressurizing direction driven by the pressurizing device 200, and gradually press fit to the wafer pair in this posture, so that the wafer pair receives a more uniform pressure bonding force, that is, the pressure uniformity of the bonding process is improved.

[0050] It should be noted that the specific structure of the leveling mechanism 500 and the principle of realizing leveling are mature technologies in the art, and the present embodiment does not improve them, so they will not be described again.

[0051] Please continue to refer to Figure 2 and Figure 3 In the present embodiment, the pressure applying device 200 can further include a mounting seat 250, wherein the mounting seat 250 is fixedly connected with the pressurizing cavity 230, and the pressure driving mechanism 210 is movably mounted on the mounting seat 250 in the pressurizing direction; a guide structure 260 is arranged between the pressure driving mechanism 210 and the mounting seat 250, and the guide structure 260 is used to guide the movement of the pressure driving mechanism 210.

[0052] In the process of driving the pressurizing shaft 220 to move by ventilating the air inlet 2311, the pressure driving mechanism 210 moves together with the pressurizing shaft 220, and in the process of moving the pressure driving mechanism 210, the guide structure 260 guides it to ensure that the moving direction of the pressurizing shaft 220 is always along the pressurizing direction, preventing the pressurizing shaft 220 from deviating, thereby further improving the uniformity of the pressure of the bonding process.

[0053] Please continue to refer to Figure 3 In the present embodiment, the pressure applying device 200 can further include a direction feedback unit 270, wherein the direction feedback unit 270 is arranged on the mounting seat 250, and the direction feedback unit 270 is used to monitor the moving direction of the pressurizing shaft 220.

[0054] By arranging the above-mentioned direction feedback unit 270, the moving direction of the pressurizing shaft 220 can be monitored, avoiding uneven stress on the wafer due to deviation of the pressurizing shaft 220.

[0055] In the present embodiment, the direction feedback unit 270 can be a grating system, which monitors the moving direction of the pressurizing shaft 220 by position feedback.

[0056] It should be noted that how to use the grating system to monitor the moving direction of the pressurizing shaft 220 can be obtained by those skilled in the art according to the prior art, and the present embodiment does not improve it, so it will not be described again.

[0057] In the present embodiment, the air inlet 2311 is provided with an air inlet control device (not shown in the figure), which is used to control the air inlet flow of the air inlet 2311; the air outlet 2312 is provided with an air outlet control device (not shown in the figure), which is used to control the air outlet flow of the air outlet 2312.

[0058] By setting the air intake control device at the air intake port 2311, real-time control of the air intake flow can be realized, and by setting the air outlet control device at the air outlet port 2312, real-time control of the air outlet flow can be realized, so that the wafer bonding machine can accurately control the displacement of the pressurizing shaft 220 according to the air intake flow and the air outlet flow during the bonding process, thereby improving the bonding precision.

[0059] Figure 4 A structure schematic diagram of the pressure head 300 of the wafer bonding machine provided in the embodiment is shown. Please continue to refer to Figure 2 , and combine Figure 4 In the embodiment, the first pressure plate 310 can include an upper cold plate 311, an upper heating plate 312 and an upper pressure plate 313 arranged in sequence from top to bottom, wherein the upper cold plate 311 and the upper heating plate 312 can approach or move away from each other; the second pressure plate 320 can include a lower pressure plate 323, a lower heating plate 322 and a lower cold plate 321 arranged in sequence from top to bottom, wherein the lower cold plate 321 and the lower heating plate 322 can approach or move away from each other.

[0060] By setting the upper heating plate 312 in the first pressure plate 310 and the lower heating plate 322 in the second pressure plate 320, the first pressure plate 310 and the second pressure plate 320 both have heating functions, so that both wafers of the wafer pair can be heated during the bonding process, effectively eliminating the situation of uneven temperature of the two wafers caused by one-sided heating, reducing the warping of the wafer pair caused by uneven temperature, and improving the bonding process yield.

[0061] In addition, by setting the upper cold plate 311 and the upper heating plate 312 in the first pressure plate 310 as a separated structure, and by setting the lower cold plate 321 and the lower heating plate 322 in the second pressure plate 320 as a separated structure, the cold plate can be away from the corresponding heating plate during heating and always in a cooling state to act as a heat insulation plate; when cooling is needed, the cold plate can be made to approach and tightly adhere to the corresponding heating plate to improve the cooling speed. When the cold plate tightly adheres to the corresponding heating plate, the cooling speed of the wafer pair can reach 20 ℃ / min.

[0062] It should be noted that the approaching and moving away of the upper cold plate 311 and the upper heating plate 312 and the lower cold plate 321 and the lower heating plate 322 can be realized by different linear drive mechanisms, respectively. Specifically, the upper heating plate 312 can be set in a fixed state, and the linear drive mechanism is used to drive the upper cold plate 311 to move up and down to realize the approaching or moving away of the upper cold plate 311 and the upper heating plate 312. Similarly, in the second pressure plate 320, the lower heating plate 322 can be set in a fixed state, and another linear drive mechanism is used to drive the lower cold plate 321 to move up and down to realize the approaching or moving away of the lower cold plate 321 and the lower heating plate 322.

[0063] In this embodiment, both the upper cooling plate 311 and the lower cooling plate 321 may be provided with cooling channels (not shown in the figure), and the cooling channels are configured to circulate cooling fluid. The cooling fluid may be a liquid fluid such as coolant.

[0064] This type of cold plate, which utilizes the flow of cooling fluid in the cooling channel to achieve cooling, has a simple structure and high cooling efficiency.

[0065] Figure 5 This is a partial longitudinal cross-sectional view of the pressure application device 200 of the wafer bonding machine provided in this embodiment. Figure 5 As shown, in this embodiment, the working process of the pressure application device 200 is as follows: First, the pressure driving mechanism 210 drives the first pressure plate 310 to descend until the lower surface of the first pressure plate 310 is 300-500 μm away from the wafer pair, keeping the first pressure plate 310 at this height. During this process, the pressure driving mechanism 210 overcomes the vacuum suction inside the vacuum chamber 100 so that the position of the first pressure plate 310 is not affected by the vacuum chamber 100. Second, the airflow pressure is controlled by the air intake control device. Under the action of the airflow pressure, the bellows expands and elongates, and the pressure shaft 220 moves along the pressure direction so that the first pressure plate 310 contacts the wafer pair and begins to apply bonding pressure. At the same time, the airflow pressure inside the bellows is measured by the air outlet control device, and the input airflow pressure is fed back and controlled. Finally, the airflow pressure continues to be applied to the inside of the bellows by the air intake control device. If the applied airflow pressure of 1.5 MPa is applied to the pressure shaft 220, the pressure-bearing area is approximately 0.015 m². 2 This allows for a bonding pressure of 20KN. During this process, the pressure sensor 400 provides real-time feedback on the bonding pressure, and the output airflow pressure is adjusted by the air outlet control device to achieve high-precision bonding pressure control.

[0066] The bonding pressure is indirectly transmitted to the first pressure plate 310 through the pressure shaft 220, so that the diameter of the bellows is not affected by the diameter change of the wafer, thereby maximizing the uniformity of the stress on the structure, eliminating the resulting structural deformation, and ensuring pressure uniformity.

[0067] In the working process of the wafer bonding machine, a wafer pair is clamped on the second pressing plate 320, and the thickness of the wafer pair is 300-2000 μm. In the wafer pair bonding process, the wafer pair with the clamp after alignment is placed in the vacuum cavity 100; the vacuum cavity 100 is vacuumized, and pressure is applied after the process vacuum environment 1E-3 mbar is reached; when the pressure is applied, the first pressing plate 310 is first driven to descend by the pressure driving mechanism 210, is quickly moved to a position close to the wafer pair (for example, a position 300-500 μm away from the wafer pair), and is kept at the position; the gas flow is introduced from the gas inlet 2311, the gas flow pressure is applied to the pressurizing shaft 220, the first pressing plate 310 contacts the wafer pair, and the pressure (the pressure range can be 0-100 KN), heating (the heating temperature can be room temperature-550 ℃), and cooling are carried out according to the preset bonding process requirements; after the bonding is completed, the vacuum cavity 100 is broken, the vacuum cavity 100 is opened, and the bonded wafer pair and the clamp are taken out.

[0068] Although the utility model discloses as above, the utility model is not limited to this. Any person skilled in the art, without departing from the spirit and scope of the utility model, can make various changes and modifications, therefore the protection scope of the utility model should be the range defined by the claims.

[0069] Finally, it should also be noted that in this document, relational terms such as first and second and the like can be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises", "comprising", "has", "having", "includes", "including", or any other variation thereof, are intended to cover a non-exclusive inclusion such that a process, method, article, or apparatus that comprises, has, includes, or consists of a list of elements does not include only those elements but can include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without limitation, an element preceded by "comprises... a" does not, without more constraints, foreclose the existence of additional identical elements in the process, method, article, or apparatus that comprises, has, includes, or consists of that element.

[0070] In the above embodiments, the description of the orientation such as "upper", "lower", "side" and the like is based on the drawings.

[0071] The above description of disclosed embodiments enables a person skilled in the art to implement or use the utility model. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the utility model. Therefore, the utility model will not be limited to these embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A wafer bonding machine, characterized in that, The device includes a vacuum chamber (100), a pressure device (200) located outside the vacuum chamber (100), and a pressure head (300) located inside the vacuum chamber (100). The pressure device (200) includes a pressure drive mechanism (210), a pressure shaft (220), a pressure chamber (230), and a reset element (240). The pressure drive mechanism (210) is connected to the pressure shaft (220), and the pressure shaft (220) movably passes through the pressure chamber (230) along the pressure direction. The pressure shaft (220) is provided with a piston boss (240). 21); The pressurizing chamber (230) has an air inlet (2311) for allowing airflow to enter and act on the piston boss (221) and an air outlet (2312) for allowing airflow to exit. The reset element (240) is configured to make the pressurizing shaft (220) always have a tendency to move in the decompression direction. The pressure head (300) includes a first pressure plate (310) and a second pressure plate (320). The first pressure plate (310) is mounted on the pressurizing shaft (220), and the second pressure plate (320) is mounted on the vacuum chamber (100).

2. The wafer bonding machine according to claim 1, characterized in that, The reset element (240) includes a bellows located inside the pressurizing chamber (230) and fitted onto the pressurizing shaft (220). The first end of the bellows is sealed to the pressurizing chamber (230), and the second end of the bellows is sealed to the piston boss (221). The inner cavity of the bellows is connected to both the air inlet (2311) and the air outlet (2312).

3. The wafer bonding machine according to claim 2, characterized in that, The pressurization chamber (230) includes a top plate (231), a support ring (232), and a bottom plate (233). The bottom plate (233) is fixedly disposed relative to the vacuum chamber (100). The support ring (232) is fixedly connected to the bottom plate (233), and the top plate (231) is fixedly connected to the support ring (232). The air inlet (2311) and the air outlet (2312) are both located on the top plate (231). The first end of the corrugated pipe is sealed to the top plate (231); the top plate (231) has a top through hole (2313), the bottom plate (233) has a bottom through hole (2331), the pressure shaft (220) passes through the top through hole (2313) and the bottom through hole (2331), and a sealing structure (234) is provided between the pressure shaft (220) and the hole wall of the bottom through hole (2331).

4. The wafer bonding machine according to claim 1, characterized in that, The wafer bonding machine also includes a pressure sensor (400), which is installed between the pressure shaft (220) and the first pressure plate (310). The pressure sensor (400) is used to sense the pressure on the pressure shaft (220).

5. The wafer bonding machine according to claim 4, characterized in that, The wafer bonding machine further includes a leveling mechanism (500), which is disposed between the pressure sensor (400) and the first pressure plate (310). The leveling mechanism (500) is used to adjust the parallelism of the first pressure plate (310).

6. The wafer bonding machine according to claim 1, characterized in that, The pressure application device (200) further includes a mounting base (250), which is fixedly connected to the pressure chamber (230). The pressure driving mechanism (210) is movably mounted on the mounting base (250) along the pressure direction. A guide structure (260) is provided between the pressure driving mechanism (210) and the mounting base (250), which is used to guide the pressure driving mechanism (210) to move.

7. The wafer bonding machine according to claim 6, characterized in that, The pressure application device (200) further includes a direction feedback unit (270), which is disposed on the mounting base (250) and is used to monitor the movement direction of the pressure shaft (220).

8. The wafer bonding machine according to claim 1, characterized in that, The air inlet (2311) is provided with an air intake control device, which is used to control the air intake flow rate of the air inlet (2311); the air outlet (2312) is provided with an air outlet control device, which is used to control the air outlet flow rate of the air outlet (2312).

9. The wafer bonding machine according to any one of claims 1-8, characterized in that, The first pressure plate (310) includes an upper cooling plate (311), an upper heating plate (312), and an upper pressure plate (313) arranged sequentially from top to bottom, wherein the upper cooling plate (311) and the upper heating plate (312) can move closer to each other or further away from each other; the second pressure plate (320) includes a lower pressure plate (323), a lower heating plate (322), and a lower cooling plate (321) arranged sequentially from top to bottom, wherein the lower cooling plate (321) and the lower heating plate (322) can move closer to each other or further away from each other.

10. The wafer bonding machine according to claim 8, characterized in that, Both the upper cooling plate (311) and the lower cooling plate (321) are provided with cooling channels, which are configured to circulate cooling fluid.

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