Wafer bonding platform and wafer bonding method

Abstract

The application belongs to the technical field of semiconductor material bonding, and discloses a wafer bonding platform and a wafer bonding method. The wafer bonding platform comprises a chamber, the chamber comprises an upper press head module, a lower press head module and a transfer tool, the transfer tool is fixed in the chamber through a base, a driving structure is arranged on the base and used for driving the transfer tool to ascend and descend along a vertical direction, the transfer tool is provided with a avoiding space and a plurality of suction accessories arranged outside the avoiding space, when a mechanical hand is placed in the avoiding space, all the suction accessories are used to adsorb the front surface of a wafer, the wafer is adsorbed from multiple positions by the suction accessories, so that the wafer is kept horizontal, after the transfer tool cooperates with the mechanical hand to complete wafer transfer, the transfer tool continues to ascend along the vertical direction, so that the wafer is flatly abutted on a wafer chuck of the upper press head module, effectively solving the problem of wafer edge collapse, and improving the uniformity of whole surface adsorption when the wafer is adsorbed by the wafer chuck in the following step.

Description

Technical Field

[0001] This invention relates to the field of semiconductor material bonding technology, and more particularly to a wafer bonding platform and a wafer bonding method. Background Technology

[0002] Currently, wafer bonding mainly uses the front-side direct bonding method, which typically includes an upper bonding head to hold the upper wafer, and a lower bonding head to support the lower wafer. One of the upper and lower bonding heads can move at least in the XY direction, and the other can move at least in the Z direction. The upper and lower wafers are aligned by the XY movement, and bonding pressure is applied by the Z movement.

[0003] Large (such as the current 12-inch) and thin (tens of micrometers or even micrometers) wafers are the industry trend, but this has caused problems with wafer loading: the loading head 100 is usually inverted and uses an adsorption method to pick up the wafer 300. The large and thin wafer 300 itself will collapse at the edges, such as... Figure 1 The robotic arm used for transferring wafers may also tilt due to the downward droop of the robotic arm end due to gravity. The combination of these two factors makes it difficult for the upper wafer 300 to be flatly adsorbed on the upper pressure head 100, making it impossible to perform subsequent alignment of the upper and lower wafers and thus preventing bonding.

[0004] Traditional wafer loading methods involve first loading the upper wafer 300 onto the lower pressure head 200, where it is supported by pins. Then, the upper pressure head picks up the upper wafer 300 from the pins. However, the pin lifting process also suffers from edge collapse issues, such as... Figure 2 Increasing the number of pins or the area of ​​the pins may solve the problem of edge collapse, but it will leave more holes in the pressure head after the pins are removed. During bonding, the stress at the holes will be uneven, resulting in poor bonding.

[0005] Therefore, there is a need to provide a wafer bonding platform and a wafer bonding method to solve the above problems. Summary of the Invention

[0006] The purpose of this invention is to provide a wafer bonding platform and a wafer bonding method to cooperate with a robot to complete wafer handover and flatly abut the wafer against the wafer chuck of the upper pressure head module, thereby solving the wafer edge collapse problem. This can prevent the deviation introduced by the robot cantilever effect from being transmitted to subsequent stages, and also prevent holes left by using PIN needles for feeding, thereby improving the uniformity of the entire surface adsorption when the wafer is inverted and adsorbed by the wafer chuck.

[0007] To achieve this objective, the present invention adopts the following technical solution:

[0008] This invention provides a wafer bonding platform, including a chamber comprising an upper pressure head module, a lower pressure head module, and a transfer fixture. The transfer fixture is fixed within the chamber via a base. The base is provided with a driving structure for driving the transfer fixture to move vertically up and down. The transfer fixture is provided with a clearance space and multiple adsorption components arranged outside the clearance space. The clearance space is used to accommodate a robotic arm supporting the wafer. All the adsorption components cooperate to support and adsorb the front side of the wafer, keeping the wafer horizontal. The driving structure drives the transfer fixture to rise, so as to flatly abut the wafer against the wafer chuck of the upper pressure head module. The lower pressure head module is used to cooperate with the upper pressure head module to perform bonding.

[0009] As an optional technical solution for a wafer bonding platform, it also includes a negative pressure system. The adsorption element is a suction head. One end of the adsorption element is connected to the negative pressure system, and the other end of the adsorption element is used to adsorb the wafer. The negative pressure system is used to provide negative pressure to the adsorption element and detect the negative pressure value.

[0010] As an optional technical solution for a wafer bonding platform, the handover fixture includes a mounting plate, a support member, and a carrier plate. The mounting plate is connected to the driving structure, the adsorption member is fixed to the carrier plate, and the carrier plate is connected to the mounting plate through the support member. The carrier plate and the mounting plate are spaced apart along the vertical direction, and the carrier plate is located on one side of the mounting plate to obtain the clearance space.

[0011] As an optional technical solution for a wafer bonding platform, there are two carrier plates and two support members. The two carrier plates are symmetrically arranged on both sides of the mounting plate, and each carrier plate is provided with at least two adsorption members.

[0012] As an optional technical solution for a wafer bonding platform, the support includes a support plate and a support column. One end of the support plate is fixed to the mounting plate, and the bearing plate is fixed to the other end of the support plate by the support column. The width of the support plate gradually increases in the direction away from the mounting plate.

[0013] As an optional technical solution for a wafer bonding platform, the carrier plate is provided with mounting holes, and the adsorption component passes through the mounting holes and is fixed to the carrier plate by nuts.

[0014] As an alternative technology for wafer bonding platforms, the adsorption element is at least partially made of a flexible material.

[0015] As an optional technical solution for a wafer bonding platform, the adsorption element is used to adsorb the edge of the front side of the wafer. The adsorption elements are arranged in an arc-shaped interval around the clearance space or symmetrically arranged on both sides of the clearance space.

[0016] As an optional technical solution for a wafer bonding platform, the driving structure includes a fixed plate, a driving component, and an auxiliary plate. The driving component is fixed to the base via the fixed plate. The auxiliary plate and the fixed plate slide together in the vertical direction. The transfer fixture is fixed to the auxiliary plate. The driving component drives the auxiliary plate to move, thereby raising and lowering the transfer fixture.

[0017] This invention provides a wafer bonding method, which utilizes the aforementioned wafer bonding platform and includes the following steps:

[0018] The transfer fixture is positioned below the initial position of the robotic arm. The robotic arm transfers the wafer to a position above the transfer fixture. The transfer fixture is then driven by a drive structure to rise to the first target position, so that the robotic arm is placed within the clearance space. The suction device of the transfer fixture is then activated to suction the front side of the wafer.

[0019] After the robotic arm withdraws from the clearance space, the handover fixture is driven to rise to the second target position so that the wafer is flatly abutted against the wafer chuck of the upper pressure head module;

[0020] The wafer chuck adsorbs the wafer, and the upper pressure head module and lower pressure head module align and perform bonding.

[0021] As an optional technical solution for wafer bonding, after the adsorption device is activated, it is determined whether all the adsorption devices are in an adsorption state. If all are adsorbed, the robot arm is withdrawn from the clearance space. If any of the adsorption devices are not adsorbed, the machine is stopped for inspection.

[0022] Beneficial effects:

[0023] This invention provides a wafer bonding platform, which includes a chamber comprising an upper pressure head module, a lower pressure head module, and a transfer fixture. The transfer fixture is fixed within the chamber by a base. The base is provided with a driving structure for driving the transfer fixture to move up and down vertically. The transfer fixture is provided with a clearance space and multiple adsorption components arranged outside the clearance space. The clearance space is used to accommodate a robotic arm that supports the wafer. All adsorption components cooperate to support and adsorb the front side of the wafer, keeping the wafer horizontal. The driving structure drives the transfer fixture to rise, so as to flatly abut the wafer against the wafer chuck of the upper pressure head module. The lower pressure head module is used to cooperate with the upper pressure head module to perform bonding. A transfer fixture is installed on a base inside the cavity. A drive structure is installed on the base to drive the transfer fixture to move vertically up and down. The transfer fixture has a clearance space and multiple adsorption components arranged outside the clearance space. When the robot is placed in the clearance space, all adsorption components adsorb the front side of the wafer. The wafer is adsorbed from multiple positions by the adsorption components to help keep the wafer horizontal. After the transfer fixture and robot complete the wafer transfer, the transfer fixture continues to rise vertically, so that the wafer is flat against the wafer chuck of the upper pressure head module. This effectively solves the wafer edge collapse problem. The wafer bonding platform replaces the robot to stably support and transfer the wafer, which can prevent the deviation introduced by the robot cantilever effect from being transmitted to subsequent stages. It can also prevent holes left by the PIN needle loading and improve the uniformity of the whole-face adsorption when the wafer is inverted and adsorbed by the wafer chuck.

[0024] This invention provides a wafer bonding method. Using the aforementioned wafer bonding platform, the transfer fixture is positioned below the initial position of the robotic arm. The robotic arm transfers the wafer above the transfer fixture, and a drive structure propels the transfer fixture to a first target position, placing the robotic arm within a clearance space. The suction element of the transfer fixture then adsorbs the front side of the wafer. After the robotic arm leaves the clearance space, the transfer fixture is driven to a second target position, flatly abutting the wafer against the wafer chuck of the upper pressure head module. The wafer chuck adsorbs the wafer, and the upper and lower pressure head modules align and perform bonding, improving the stability and precision of wafer processing. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of a traditional structure that uses robotic arms for material handling.

[0026] Figure 2 This is a schematic diagram of a traditional PIN-based feeding structure;

[0027] Figure 3 This is a schematic diagram of the wafer bonding platform provided in an embodiment of the present invention;

[0028] Figure 4 This is a partial structural schematic diagram of the wafer bonding platform provided in an embodiment of the present invention;

[0029] Figure 5 This is a front view of a portion of the wafer bonding platform provided in an embodiment of the present invention;

[0030] Figure 6 This is a schematic diagram of the handover tooling, base, and drive structure provided in an embodiment of the present invention;

[0031] Figure 7 yes Figure 6 A magnified view of a section at point A in the middle;

[0032] Figure 8 This is a schematic diagram of the handover tooling provided in an embodiment of the present invention;

[0033] Figure 9 This is a schematic diagram of the structure of the adsorption component and nut provided in the embodiment of the present invention.

[0034] In the picture:

[0035] 100. Upper pressure head; 200. Lower pressure head; 300. Wafer loading;

[0036] 1. Upper pressure head module; 1a. Wafer chuck; 2. Lower pressure head module; 3. Wafer;

[0037] 10. Handover fixture; 10a. Clearance space; 11. Mounting plate; 12. Support component; 121. Support plate; 122. Support column; 13. Bearing plate; 131. Mounting hole; 14. Adsorption component; 141. Flexible part; 15. Nut;

[0038] 20. Base; 21. Bottom plate; 22. Top plate; 23. Web plate;

[0039] 30. Drive structure; 31. Fixing plate; 32. Drive component; 33. Auxiliary plate. Detailed Implementation

[0040] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0041] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0042] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0043] In the description of this embodiment, the terms "upper," "lower," "left," and "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0044] like Figures 3 to 8 As shown, this embodiment provides a wafer bonding platform, which includes a chamber. The chamber includes an upper pressure head module 1, a lower pressure head module 2, and a transfer fixture 10. The transfer fixture 10 is fixed in the chamber by a base 20. The base 20 is provided with a driving structure 30 for driving the transfer fixture 10 to move up and down in the vertical direction. The transfer fixture 10 is provided with a clearance space 10a and a plurality of adsorption components 14 arranged outside the clearance space 10a. The clearance space 10a is used to accommodate a robotic arm that supports the wafer 3. All adsorption components 14 are used to support and adsorb the front side of the wafer 3 and keep the wafer 3 horizontal. The driving structure 30 drives the transfer fixture 10 to rise so that the wafer 3 is flatly abutted against the wafer chuck 1a of the upper pressure head module 1. The lower pressure head module 2 is used to cooperate with the upper pressure head module 1 to perform bonding.

[0045] A transfer fixture 10 is installed on a base 20 inside the cavity. A drive structure 30 is installed on the base 20 to drive the transfer fixture 10 to move vertically. The transfer fixture 10 has a clearance space 10a and multiple adsorption components 14 arranged outside the clearance space 10a. When the robot arm is placed in the clearance space 10a, all adsorption components 14 are used to adsorb the front side of the wafer 3. The wafer 3 is adsorbed by the adsorption components 14 from multiple positions, thereby helping to keep the wafer 3 horizontal. The transfer fixture 10 works in conjunction with the robot arm to complete the transfer. After the wafer 3 is handed over, the handover fixture 10 continues to rise vertically, so that the wafer 3 is flatly abutted against the wafer chuck 1a of the upper pressure head module 1, which effectively solves the problem of wafer 3 edge collapse. In addition, the wafer bonding platform replaces the robot arm to stably support and transfer the wafer 3, which can prevent the deviation introduced by the robot arm cantilever effect from being transmitted to subsequent stages. It can also prevent holes left by the use of PIN needle loading, and improve the uniformity of the whole surface adsorption when the wafer 3 is inverted and adsorbed by the wafer chuck 1a.

[0046] The chamber can be selectively evacuated to become a vacuum chamber. For example, the chamber is usually equipped with a gate valve and a vacuum pump. The vacuum pump is controlled by opening and closing the gate valve to extract the gas from the chamber. One of the lower pressure head module 2 and the upper pressure head module 1 can move at least horizontally and the other can move at least vertically. The wafer is aligned by horizontal movement and bonding pressure is applied by vertical movement. The wafer 3 has a front side and a back side, which are arranged opposite to each other along the thickness direction of the wafer 3. The wafer is inverted, which means that the wafer 3 is facing down. When wafer 3 is taken out of the wafer cassette, the robot arm is inserted parallel to the gap between wafers 3 in the cassette. After picking up wafer 3, the robot arm unfolds it. At this time, the wafer 3 picked up by the robot arm is facing up. Wafer 3 needs to be flipped through the flipping station to be inverted. Then the robot arm takes wafer 3 away from the flipping station. At this time, wafer 3 is in an inverted state with its face down. The robot arm is in contact with the face of wafer 3. Then the transfer fixture 10 rises vertically so that the adsorption component 14 is placed below the face of wafer 3. At this time, the robot arm is placed in the clearance space 10a. Then the adsorption component 14 adsorbs the face of wafer 3. After the transfer fixture 10 completes the wafer transfer from the robot arm, the wafer 3 adsorbed on the transfer fixture 10 is still in an inverted state with its face down.

[0047] Specifically, the base 20 includes a bottom plate 21, a top plate 22 and two web plates 23. The top plate 22 is connected to the bottom plate 21 through the two web plates 23. The bottom plate 21 and the top plate 22 are spaced apart in the vertical direction.

[0048] The driving structure 30 includes a fixed plate 31, a driving component 32, and an auxiliary plate 33. The driving component 32 is fixed to the base 20 via the fixed plate 31. The auxiliary plate 33 slides vertically with the fixed plate 31. The transfer fixture 10 is fixed to the auxiliary plate 33. The driving component 32 drives the auxiliary plate 33 to move, thereby raising and lowering the transfer fixture 10. The sliding engagement between the auxiliary plate 33 and the fixed plate 31 provides a vertical guide, ensuring that the auxiliary plate 33 does not shift during the raising and lowering process, thus driving the transfer fixture 10 to rise and fall vertically.

[0049] In this embodiment, the fixing plate 31 is fixed to the top plate 22 by bolts, the driving component 32 is fixed to the fixing plate 31, one side of the fixing plate 31 is slidably engaged with the auxiliary plate 33 in the vertical direction, the output end of the driving component 32 is connected to the bottom end of the auxiliary plate 33, and the top end of the auxiliary plate 33 is fixedly connected to the handover fixture 10 by bolts; the driving component 32 includes, but is not limited to, a motor.

[0050] Optionally, the wafer bonding platform also includes a negative pressure system, with the adsorption element 14 being a suction head. One end of the adsorption element 14 is connected to the negative pressure system, and the other end of the adsorption element 14 is used to adsorb the wafer 3. The negative pressure system is used to provide negative pressure to the adsorption element 14 and detect the negative pressure value.

[0051] The suction head is used as the adsorption component 14, and a negative pressure system provides negative pressure to the suction head. When the wafer 3 is placed above the suction head, the negative pressure system can detect the negative pressure value of the suction head. The negative pressure value is kept within an appropriate range to ensure that the wafer 3 is firmly and safely adsorbed, avoiding the wafer 3 from shifting due to insufficient suction or damaging the wafer 3 due to excessive suction. If the negative pressure value is too small, it means that the wafer 3 is not correctly placed on all the adsorption components 14. Once the wafer 3 is deviated, the negative pressure system can play a timely monitoring role, trigger an alarm, realize stable support and position detection of the wafer 3, correct deviation in time, and prevent the wafer 3 from slipping or the picking and placing deviation from being transmitted to subsequent stages and causing a chain of quality problems.

[0052] It is understood that in other embodiments, suction cups may also be used as adsorption components 14, with multiple suction cups dispersed to adsorb wafers 3, thereby keeping wafers 3 in a horizontal position.

[0053] Furthermore, the handover fixture 10 includes a mounting plate 11, a support member 12, and a bearing plate 13. The mounting plate 11 is connected to the drive structure 30, the adsorption member 14 is fixed to the bearing plate 13, and the bearing plate 13 is connected to the mounting plate 11 through the support member 12. The bearing plate 13 and the mounting plate 11 are spaced apart in the vertical direction, and the bearing plate 13 is located on one side of the mounting plate 11 to obtain a clearance space 10a.

[0054] The design supports 12 connect the mounting plate 11 and the bearing plate 13. The bearing plate 13 is placed on one side of the mounting plate 11 to avoid the robot arm horizontally. The bearing plate 13 and the mounting plate 11 are arranged vertically to avoid the robot arm vertically, thereby forming a sufficient avoidance space 10a.

[0055] In this embodiment, there are two carrier plates 13 and two support members 12. The two carrier plates 13 are symmetrically arranged on both sides of the mounting plate 11, and each carrier plate 13 is provided with at least two adsorption members 14. With two carrier plates 13 and two support members 12, and the two carrier plates 13 are symmetrically arranged, the carrier plates 13, support members 12 and mounting plate 11 together form a U-shaped structure, and a clearance space 10a is formed in the middle. When the robot is placed in the clearance space 10a, at least two adsorption members 14 on each carrier plate 13 disperse and adsorb the wafer 3, so that the wafer 3 is in a horizontal state and remains flat, avoiding the edge collapse of the large-size wafer due to its own weight. The adsorption force of the adsorption members 14 can also prevent the center of the wafer 3 from being concave.

[0056] In this embodiment, the Z direction is the thickness direction of the mounting plate 11 and is vertical, the X direction is the length direction of the mounting plate 11, and the Y direction is the width direction of the mounting plate 11; the upper pressure head module 1 is configured to move along the X direction, the lower pressure head module 2 is configured to rise and fall along the Z direction, and the handover fixture 10 rises and falls along the Z direction; two support plates 13 are spaced apart along the X direction, the support plates 13 extend along the Y direction, and both ends of the support plates 13 are provided with adsorption members 14.

[0057] The mounting plate 11 and the carrier plate 13 are designed to extend in different directions, and adsorption components 14 are provided at both ends of the carrier plate 13, so that the adsorption components 14 are closer to the edge of the wafer 3, which helps to improve the support effect of the wafer 3 and enhance the edge stability of the wafer 3.

[0058] In this embodiment, the carrier plate 13 is a rectangular flat plate; the adsorption element 14 is used to adsorb the front edge of the wafer 3, and the adsorption element 14 is symmetrically arranged on both sides of the clearance space 10a. Adsorbing the edge of the wafer 3 can reduce the pressure interference on the central area of ​​the wafer 3, and provide support for the edge of the wafer 3 to prevent the edge of the wafer 3 from collapsing during transportation or residence; the symmetrical arrangement of the adsorption element 14 on both sides can ensure that the wafer 3 is subjected to uniform force when it is adsorbed, avoid the wafer 3 bending or breaking due to unilateral stress, and the adsorption force of the adsorption element 14 can prevent the center of the wafer 3 from being concave. In other embodiments, one or more carrier plates 13 may be provided, and each carrier plate 13 is provided with an adsorption element 14; the carrier plate 13 may also be an arc-shaped plate, and the adsorption element 14 is designed to be arranged in an arc-shaped interval around the clearance space 10a.

[0059] Specifically, the support member 12 includes a support plate 121 and a support column 122. One end of the support plate 121 is fixed to the mounting plate 11, and the bearing plate 13 is fixed to the other end of the support plate 121 via the support column 122. The width of the support plate 121 gradually increases in the direction away from the mounting plate 11. The fixed connection between the support plate 121 and the support column 122 provides a stable support foundation for the bearing plate 13. The design of the support plate 121 gradually increasing in width in the direction away from the mounting plate 11 can enhance the stability and load-bearing capacity of the support member 12, effectively disperse stress, and prevent deformation or vibration caused by uneven stress.

[0060] In this embodiment, the planes on which the mounting plate 11 and the support plate 121 are located are parallel. The central area of ​​the bottom surface of the mounting plate 11 is fixedly connected to the top of the auxiliary plate 33. The mounting plate 11 is connected to a support plate 121 at each end in the X direction. The support column 122 extends along the Z direction. The bottom end of the support column 122 is fixed to the support plate 121, and the bearing plate 13 is fixed to the top of the support column 122. Two support columns 122 are fixed at the end of each support plate 121 away from the mounting plate 11, and the two support columns 122 are spaced apart along the Y direction.

[0061] In this embodiment, a support plate 121 is overlapped and fixed at both ends of the mounting plate 11. This overlapped fixing design effectively distributes and transfers loads, enhances stability, and improves the structure's tensile, shear, and bending resistance. The mounting plate 11 and the support plate 121 are fixed together by bolts.

[0062] See Figure 7 The support plate 13 has mounting holes 131, and the adsorption component 14 passes through the mounting holes 131 and is fixed to the support plate 13 by nuts 15. Fixing the adsorption component 14 with nuts 15 can prevent the adsorption component 14 from shifting, and can also easily disassemble and install the adsorption component 14 for quick replacement and reduced downtime.

[0063] In this embodiment, the mounting hole 131 is an oblong hole, and the position of the adsorption element 14 is adjustable along the length of the oblong hole. The oblong hole design allows for fine-tuning of the position of the adsorption element 14, facilitating calibration or replacement of adsorption elements 14 of different specifications, enabling it to adapt to wafers 3 of various sizes, thus enhancing flexibility and applicability.

[0064] See Figure 9 The adsorption member 14 is at least partially made of a flexible material. The elastic deformation of the flexible material provides a buffer for the wafer 3, preventing direct impact when the wafer 3 is between the transfer fixture 10 and the wafer chuck 1a. In this embodiment, the top of the adsorption member 14 has a flexible portion 141 made of a flexible material, and the suction head on the flexible portion 141 is used to adsorb the wafer 3.

[0065] This embodiment also provides a wafer bonding method, which utilizes the aforementioned wafer bonding platform and includes the following steps:

[0066] Step S1: Place the transfer fixture 10 below the initial position of the robot arm. The robot arm transfers the wafer 3 above the transfer fixture 10. The drive structure 30 drives the transfer fixture 10 to rise to the first target position so that the robot arm is placed in the clearance space 10a. The adsorption component 14 of the transfer fixture 10 is activated to adsorb the front side of the wafer 3.

[0067] Before the drive structure 30 is started, the robot arm needs to pick up the wafer 3 from the wafer cassette. Specifically, when taking out the wafer 3 from the wafer cassette, the robot arm is inserted parallel to the gap between the wafers 3 in the cassette. After picking up the wafer 3, the robot arm unfolds it. At this time, the wafer 3 picked up by the robot arm is facing up. The wafer 3 needs to be flipped through the flipping station to be inverted. Then the robot arm takes the wafer 3 away from the flipping station. At this time, the wafer 3 is in an inverted state with its face down, and the robot arm is in contact with the front of the wafer 3.

[0068] The handover fixture 10 is placed below the initial position of the robot arm. The handover fixture 10 is raised vertically to the first target position, so that the adsorption component 14 is placed below the front side of the wafer 3. At this time, the robot arm is placed in the clearance space 10a, and the adsorption component 14 is activated to adsorb the front side of the wafer 3.

[0069] In this embodiment, at the moment the adsorption member 14 is activated, the front edge of the wafer 3 is adsorbed by the adsorption member 14 of the transfer fixture 10, the center of the front of the wafer 3 is supported by the robot arm, and the edge of the wafer 3 is flush with the center. It can be understood that since the wafer 3 remains flat at this moment, after the robot arm withdraws from the clearance space 10a, the wafer 3 will be adsorbed by the adsorption member 14, forming a pulling force, and the center of the wafer 3 will not be concave.

[0070] Step S2: After the robotic arm withdraws from the clearance space 10a, the transfer fixture 10 is driven to rise to the second target position so that the wafer 3 is flatly abutted against the wafer chuck 1a of the upper pressure head module 1.

[0071] Optionally, after activating the adsorption element 14, it is determined whether all adsorption elements 14 are in an adsorption state. If all are adsorbed, the robot arm is withdrawn from the clearance space 10a. If any adsorption element 14 is not adsorbed, the machine is stopped for inspection. In this embodiment, after the adsorption element 14 adsorbs the front side of the wafer 3, it is checked whether all adsorption elements 14 have adsorbed the wafer 3, and the negative pressure value is checked using a negative pressure system. After ensuring that it is normal, the robot arm is withdrawn from the clearance space 10a, and the transfer fixture 10 rises to transfer the wafer 3 to the second target position.

[0072] Step S3: The wafer chuck 1a adsorbs the wafer 3, and the upper pressure head module 1 and the lower pressure head module 2 are aligned and bonded.

[0073] Taking the adsorption component 14, which is made of at least part of a flexible material, as an example, the robot arm horizontally pulls out the retraction clearance space 10a and drives the transfer fixture 10 to continue to rise. At this time, the wafer 3 is steadily lifted and raised in an inverted state. The wafer 3 remains horizontal until the wafer 3 is transferred to the second target position. Under the elastic deformation of the flexible material, the back of the wafer 3 and the wafer chuck 1a can be tightly and evenly attached through flexible contact, reducing the risk of bonding voids and avoiding direct impact on the wafer 3, effectively reducing the probability of damage to the wafer 3. Then the wafer chuck 1a adsorbs the wafer 3, the adsorption component 14 is closed, the upper pressure head module 1 moves along the X direction for alignment, and the lower pressure head module 2 rises along the Z direction to perform bonding and apply bonding force.

[0074] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art will be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A wafer bonding platform, characterized in that, The device includes a chamber, which includes an upper pressure head module (1), a lower pressure head module (2), and a transfer fixture (10). The transfer fixture (10) is fixed in the chamber by a base (20). The base (20) is provided with a driving structure (30) for driving the transfer fixture (10) to move up and down in the vertical direction. The transfer fixture (10) is provided with a clearance space (10a) and a plurality of adsorption components (14) arranged outside the clearance space (10a). The clearance space (10a) is used to accommodate a robotic arm that supports the wafer (3). All the adsorption components (14) are used to support and adsorb the front side of the wafer (3) and keep the wafer (3) horizontal. When the front edge of the wafer (3) is adsorbed by the adsorption member (14) of the transfer fixture (10), the center position of the front of the wafer (3) is supported by the robot arm, and the edge of the wafer (3) is flush with the center position. The drive structure (30) drives the transfer fixture (10) to rise so that the wafer (3) is flatly abutted against the wafer chuck (1a) of the upper pressure head module (1), and the lower pressure head module (2) is used to cooperate with the upper pressure head module (1) to perform bonding.

2. The wafer bonding platform according to claim 1, characterized in that, It also includes a negative pressure system. The adsorption element (14) is a suction head. One end of the adsorption element (14) is connected to the negative pressure system, and the other end of the adsorption element (14) is used to adsorb the wafer (3). The negative pressure system is used to provide negative pressure to the adsorption element (14) and detect the negative pressure value.

3. The wafer bonding platform according to claim 1, characterized in that, The handover fixture (10) includes a mounting plate (11), a support member (12), and a bearing plate (13). The mounting plate (11) is connected to the driving structure (30), and the adsorption member (14) is fixed to the bearing plate (13). The bearing plate (13) is connected to the mounting plate (11) through the support member (12). The bearing plate (13) and the mounting plate (11) are spaced apart along the vertical direction, and the bearing plate (13) is located on one side of the mounting plate (11) to obtain the clearance space (10a).

4. The wafer bonding platform according to claim 3, characterized in that, Two of each of the bearing plate (13) and the support member (12) are provided. The two bearing plates (13) are symmetrically arranged on both sides of the mounting plate (11). Each bearing plate (13) is provided with at least two adsorption members (14).

5. The wafer bonding platform according to claim 3, characterized in that, The support member (12) includes a support plate (121) and a support column (122). One end of the support plate (121) is fixed to the mounting plate (11), and the bearing plate (13) is fixed to the other end of the support plate (121) through the support column (122). The width of the support plate (121) gradually increases in the direction away from the mounting plate (11).

6. The wafer bonding platform according to claim 3, characterized in that, The support plate (13) is provided with mounting holes (131), and the adsorption component (14) passes through the mounting holes (131) and is fixed to the support plate (13) by nuts (15).

7. The wafer bonding platform according to any one of claims 1-6, characterized in that, The adsorption element (14) is at least partially made of a flexible material.

8. The wafer bonding platform according to any one of claims 1-6, characterized in that, The adsorption element (14) is used to adsorb the edge of the front side of the wafer (3). The adsorption element (14) is arranged in an arc-shaped interval around the clearance space (10a) or symmetrically arranged on both sides of the clearance space (10a).

9. The wafer bonding platform according to any one of claims 1-6, characterized in that, The driving structure (30) includes a fixed plate (31), a driving component (32) and an auxiliary plate (33). The driving component (32) is fixed to the base (20) through the fixed plate (31). The auxiliary plate (33) and the fixed plate (31) slide in the vertical direction. The handover fixture (10) is fixed to the auxiliary plate (33). The driving component (32) drives the auxiliary plate (33) to move and drive the handover fixture (10) to rise and fall.

10. A wafer bonding method, characterized in that, The application of the wafer bonding platform as described in any one of claims 1-9 includes the following steps: The transfer fixture (10) is placed below the initial position of the robot arm. The robot arm transfers the wafer (3) above the transfer fixture (10). The drive structure (30) drives the transfer fixture (10) to rise to the first target position so that the robot arm is placed in the clearance space (10a). The adsorption component (14) of the transfer fixture (10) is activated to adsorb the front side of the wafer (3). After the robotic arm withdraws from the clearance space (10a), the handover fixture (10) is driven to rise to the second target position so as to flatly abut the wafer (3) against the wafer chuck (1a) of the upper pressure head module (1); The wafer chuck (1a) adsorbs the wafer (3), and the upper pressure head module (1) and the lower pressure head module (2) are aligned and bonded.

11. The wafer bonding method according to claim 10, characterized in that, After the adsorption element (14) is activated, it is determined whether all the adsorption elements (14) are in the adsorption state. If all are adsorbed, the robot arm is removed from the clearance space (10a). If any of the adsorption elements (14) are not adsorbed, the machine is stopped for inspection.

Images