Wafer overturning and bonding mechanism and wafer bonding method

Abstract

The invention relates to the technical field of semiconductor material processing, in particular to a wafer overturning and bonding mechanism and a wafer bonding method. Comprising a first carrying platform on which a first wafer disc is configured and which is used for selectively clamping or releasing a first wafer; a second carrying platform which is provided with a second wafer disc and is used for selectively clamping a second wafer; the connecting part is used for connecting the first carrying table and the second carrying table; the first carrying table and / or the second carrying table can swing relative to the connecting part, so that the included angle between the first carrying table and the second carrying table is kept at 0-180 degrees; when the included angle between the first carrying table and the second carrying table is kept at 0 degree, the first wafer and the second wafer are attached to form a wafer overlapping body; the wafer overlapping body is clamped by the second wafer disc, and when the included angle between the first carrying table and the second carrying table is larger than 0 degree, the position of the wafer overlapping body relative to the second wafer disc is fixed. Double-layer and multi-layer wafer bonding can be carried out in a vacuum environment, and the vacuum degree in the bonding chamber can be kept stable.

Description

Technical Field

[0001] The present application relates to the technical field of semiconductor material processing, and in particular to a wafer flip bonding mechanism and a wafer bonding method. Background Art

[0002] High vacuum room temperature bonding, as an emerging wafer bonding process, has been widely used and promoted in substrate manufacturing and 3D packaging processes due to its advantages of low energy consumption and high efficiency. In high vacuum room temperature bonding equipment, the loading and clamping mechanism of the wafer is a very important component. Currently, the commonly used wafer clamping mechanisms in high vacuum environments include electrostatic chucks, vacuum adhesive bonding, etc., but both of the above mechanisms have limitations. The premise of the application of electrostatic chucks is that they must be provided with a stable power supply device and line connection. In vacuum bonding equipment, the wafer carrier needs to carry the wafer to shuttle between multiple workstations to complete different work processes, and even across different vacuum chambers. This poses a severe challenge to the power supply of the electrostatic chuck, and because the cables pass through the walls of the vacuum chamber, it is difficult for the vacuum chamber to maintain a stable vacuum degree. The vacuum adhesive bonding method needs to be carried out in the atmospheric environment, and the loading process is relatively time-consuming. Since the wafer carrier is exposed to the atmospheric environment for a long time, it is very easy to absorb air molecules, and tiny air cavities are inevitably generated between the bonding surfaces of the vacuum adhesive, the carrier and the wafer, which greatly increases the vacuum chamber evacuation time and affects the overall work efficiency of the equipment. Uneven adhesive coating will also affect the uniformity of the bonding strength of the bonding interface. Summary of the invention

[0003] The purpose of the present invention is to provide a wafer flipping bonding mechanism and a wafer bonding method, which are used to clamp wafers and perform wafer bonding in a vacuum environment. The clamping mechanism is a purely mechanical structure, and does not require cables to pass through the vacuum chamber, nor does it require the wafer to be coated with glue, thereby solving the above-mentioned problems of clamping wafers in a vacuum chamber.

[0004] To achieve this object, the present invention adopts the following technical solutions:

[0005] The wafer flip bonding mechanism comprises: a first carrier, on which a first wafer plate is arranged for selectively clamping or releasing the first wafer;

[0006] A second carrier, on which a second wafer plate is disposed, for selectively clamping a second wafer;

[0007] A connecting portion, used to connect the first carrier and the second carrier;

[0008] The first platform and / or the second platform can swing relative to the connecting portion so that the angle between the first platform and the second platform is maintained at 0-180°, for example, 10°, 20°, 45°, 60°, 90°, 120°, 135°, 150°, 165°, 180°;

[0009] When the angle between the first stage and the second stage is maintained at 0°, the first wafer and the second wafer are bonded to form a wafer stack;

[0010] The wafer stack is clamped by the second wafer disk, and when the angle between the first stage and the second stage is greater than 0°, the position of the wafer stack relative to the second wafer disk remains fixed.

[0011] Furthermore, the first carrier and the second carrier are independently configured with abutment components;

[0012] The abutment assembly comprises an abutment unit and an abutment unit mounting seat;

[0013] The abutment unit mounting seat is arranged on the stage or on the back side of the wafer disc, and the back side is the opposite side of the wafer disc and the wafer in direct contact;

[0014] The abutting unit is elastically guided and connected to the abutting unit mounting seat, and the elastic guiding connection is elastic in the guiding direction.

[0015] Further, the abutment unit is configured to have an abutment surface and a pressure-bearing surface;

[0016] When the pressure-bearing surface is not subjected to force, the abutment unit has a first state;

[0017] When the pressure-bearing surface is subjected to force, the abutting unit has a second state.

[0018] Further, the first state includes the pressure-bearing surface protruding from the front side of the wafer disc, the front side being the surface of the wafer disc in contact with the wafer, and the abutting surface abutting against the circumferential side wall of the wafer;

[0019] The second state includes the pressure-bearing surface being flush with or recessed in the front surface of the wafer disk, and the abutting surface being away from the circumferential side wall of the wafer.

[0020] Furthermore, the first carrier and the second carrier are independently configured with a crimping assembly;

[0021] The crimping assembly comprises a crimping unit and a crimping unit mounting seat;

[0022] The crimping unit mounting seat is arranged on the carrier or on the back of the wafer disc;

[0023] The crimping unit is elastically guided and connected to the crimping unit mounting seat.

[0024] Further, the crimping unit is configured to have a crimping surface for selectively crimping the wafer onto the wafer tray;

[0025] A curved surface, for selectively abutting against a circumferential side wall of the wafer;

[0026] a guide surface for receiving a driving force;

[0027] When the guide surface does not receive the driving force, the crimping unit has a third state;

[0028] When the guide surface receives the driving force, the crimping unit has a fourth state.

[0029] Further, the third state includes the pressing surface pressing the wafer onto the wafer tray;

[0030] The fourth state includes the pressing surface being away from the wafer.

[0031] Furthermore, the abutment unit disposed on the first carrier is provided with a second limiting groove;

[0032] Also included is a second plunger unit, which is disposed on the first stage or on the back side of the first wafer disc;

[0033] The second plunger unit cooperates with the second limiting groove to selectively fix the abutment unit on the first carrier.

[0034] Furthermore, the crimping unit disposed on the first carrier is provided with a first limiting groove;

[0035] It also includes a first plunger unit, which is configured on the first stage or the back side of the first wafer disc;

[0036] The first plunger unit cooperates with the first limiting groove to selectively clamp the crimping unit on the first carrier.

[0037] The above-mentioned “selective” is understood to mean different states presented when the corresponding structure is driven by external force.

[0038] Furthermore, the front side of the first wafer disk and the front side of the second wafer disk are independently provided with limiting protrusions, and the limiting protrusions are used to abut against the circumferential side walls of the wafers.

[0039] Furthermore, the first wafer tray and the second wafer tray are independently configured with avoidance holes;

[0040] The avoidance hole is used to accommodate the limiting protrusion and the pressing unit configured on the opposite wafer disk when the first wafer disk is bonded to the second wafer disk.

[0041] Furthermore, the first wafer plate and the second wafer plate are independently configured with guide holes;

[0042] When the first wafer disk is bonded to the second wafer disk, the side wall of the guide hole cooperates with the guide surface of the crimping unit arranged on the opposite wafer disk, and a driving force is applied to the guide surface.

[0043] The wafer bonding method is performed using the wafer flip bonding mechanism, and includes:

[0044] Wafer loading: fixing the first wafer and the second wafer on the first wafer plate and the second wafer plate respectively by flip-chip method; the flip-chip method is that the first wafer plate and the second wafer plate face downward;

[0045] Alignment: Flip the second carrier so that the second wafer disc faces the first wafer disc, and align the second wafer with the first wafer; after alignment, the first wafer is located above the second wafer, and the vertical distance between the first wafer and the second wafer is less than 1 cm; if the distance is too large, when the second wafer disc continues to approach the first wafer disc, when the abutment unit and the crimping unit release the first wafer, the distance will be too large, causing the first wafer to shift during the falling process, affecting the fit between the first wafer and the second wafer.

[0046] Bonding: the pressure mechanism applies pressure to the second stage from the back side of the second stage, so that the second stage continues to approach the first stage, forming a bonding force between the first wafer and the second wafer, so that the second wafer is bonded to the first wafer;

[0047] Reset: the pressure mechanism moves away from the second stage, and the second stage is turned over so that the angle between the second stage and the first stage is greater than 90°, for example, 90°, 120°, 135°, 150°, 165°, or 180°;

[0048] Unloading: removing the bonded body of the first wafer and the second wafer from the second wafer plate.

[0049] Beneficial effects of the present invention:

[0050] On the one hand, the wafer flipping and bonding mechanism provided by the present invention adopts purely mechanical structures to cooperate with each other to realize the clamping and bonding of wafers in a vacuum environment, avoiding the problem that the cables of the electrically driven wafer clamping structure need to pass through the vacuum chamber wall, affecting the vacuum stability in the vacuum chamber.

[0051] On the other hand, in the wafer flip bonding mechanism provided by the present invention, before bonding, the first wafer and the second wafer can be placed facing the same direction at the same time, which is conducive to simultaneous surface treatment of the surfaces to be bonded of the first wafer and the second wafer. After the surface treatment, they can be directly flipped and bonded, which greatly shortens the exposure time of the treated surfaces to be bonded and can improve the bonding effect.

[0052] On the other hand, the wafer flip bonding mechanism provided by the present invention can perform multi-layer wafer bonding. After the resetting step, another new wafer is taken and mounted on the first carrier, and the surface to be bonded of the new wafer and the surface to be bonded of the bonding body are surface treated and then bonded, so that a three-layer bonding structure formed by bonding the new wafer and the bonding body can be obtained. Since the second carrier can stably clamp the bonding body thereon, the above steps can be repeated to perform same-chamber bonding of multi-layer wafers. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 Schematic diagram of the overall structure of the wafer flip bonding mechanism in an embodiment of the present invention;

[0054] Figure 2 Schematic diagram of the alignment of the upper and lower wafer plates of the wafer flip bonding mechanism in an embodiment of the present invention;

[0055] Figure 3 Schematic diagram of a wafer flip bonding mechanism clamping a wafer in an embodiment of the present invention;

[0056] Figure 4 Schematic diagram of the wafer flip bonding mechanism press-connecting assembly in the embodiment of the present invention Figure 1 ;

[0057] Figure 5 Schematic diagram of the wafer flip bonding mechanism press-connecting assembly in the embodiment of the present invention Figure 2 ;

[0058] Figure 6 Schematic diagram of a wafer flip bonding mechanism crimping unit in an embodiment of the present invention;

[0059] Figure 7 Schematic diagram of the wafer flip bonding mechanism abutment assembly in an embodiment of the present invention Figure 1 ;

[0060] Figure 8 Schematic diagram of the wafer flip bonding mechanism abutment assembly in an embodiment of the present invention Figure 2 ;

[0061] Fig. 9 Schematic diagram of a wafer flip bonding mechanism abutment unit in an embodiment of the present invention;

[0062] Fig.10 Schematic diagram of the force movement of the pressing unit of the wafer flip bonding mechanism in an embodiment of the present invention;

[0063] Fig.11 Schematic diagram of the force movement of the abutment unit of the wafer flip bonding mechanism in an embodiment of the present invention;

[0064] Fig.12 is a schematic diagram of wafer activation in an embodiment of the present invention;

[0065] In the figure: 1. first carrier; 2. second carrier; 3. rotating shaft; 4. first wafer disk; 41. first wafer; 5. second wafer disk; 51. second wafer; 6. abutting assembly; 61. abutting unit; 611. abutting surface; 612. second limiting groove; 613. pressure surface; 614. second guide column; 62. abutting unit mounting seat; 63. second elastic member; 64. second plunger unit; 7. crimping assembly; 71. crimping unit; 711. arc surface; 712. crimping surface; 713. guide surface; 714. first limiting groove; 715. first guide column; 72. crimping unit mounting seat; 73. first elastic member; 74. first plunger unit; 8. limiting protrusion; 9. mounting column; 10. avoidance hole; 11. guide hole; 12. vacuum chamber; 13. activation device. DETAILED DESCRIPTION

[0066] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0067] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0068] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0069] In the description of this embodiment, the terms "upper", "lower", "right", etc., directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0070] See also Figure 1 Figure 2 , an embodiment of the present application provides a wafer flip bonding mechanism, including a first stage 1 and a second stage 2, the first stage 1 and the second stage 2 are generally in a square disc structure. A connecting portion connects the first stage 1 and the second stage 2 together. In this embodiment, the connecting portion is a rotating shaft 3, and the rotating shaft 3 is respectively connected to one side of the first stage 1 and the second stage 2, so that the first stage 1 and the second stage 2 can be flipped relative to each other. In this embodiment, through the rotating shaft 3, the angle between the first stage 1 and the second stage 2 can be maintained between 0-180°.

[0071] A first wafer tray 4 is provided on the first carrier 1, and a first wafer placement area is provided on the first wafer tray 4 for placing a first wafer 41. The first wafer placement area has a shape matching the first wafer 41. The first wafer tray 4 is provided with an abutment assembly 6, a crimping assembly 7 and a limiting protrusion 8. The abutment assembly 6, the crimping assembly 7 and the limiting protrusion 8 are arranged around the first wafer placement area, so that when the first wafer 41 is clamped on the first wafer tray 4, the abutment assembly 6, the crimping assembly 7 and the limiting protrusion 8 can simultaneously form a clamping force with the circumferential side wall of the first wafer 41.

[0072] Correspondingly, a second wafer tray 5 is provided on the second carrier 2, and a second wafer placement area is provided on the second wafer tray 5 for placing a second wafer 51. The second wafer placement area has a shape matching the second wafer 51. The second wafer tray 5 is provided with an abutment assembly 6, a crimping assembly 7 and a limiting protrusion 8. The abutment assembly 6, the crimping assembly 7 and the limiting protrusion 8 are arranged around the second wafer placement area, so that when the second wafer 51 is clamped on the second wafer tray 5, the abutment assembly 6, the crimping assembly 7 and the limiting protrusion 8 can simultaneously form a clamping force with the circumferential side wall of the second wafer 51.

[0073] See also Figure 3-11, the above-mentioned abutment assembly 6 includes an abutment unit 61 and an abutment unit mounting seat 62. In the present embodiment, the abutment unit mounting seat 62 is mounted on the back side of the wafer disc, and is provided with a guide hole for limiting the moving direction of the abutment unit 61. The abutment unit 61 includes a second guide column 614, and the second guide column 614 is confined in the guide hole in the abutment unit mounting seat 62. A second elastic member 63 is disposed outside the second guide column 614. In the present embodiment, the second elastic member 63 is a coil spring, which is used to configure elastic force between the abutment unit 61 and the abutment unit mounting seat 62. The abutment unit 61 includes an abutment surface 611 and a pressure surface 613. In the present embodiment, a hollow area is provided on the wafer disc, and the hollow area enables the abutment unit 61 to reciprocate between the front and back sides of the wafer disc.

[0074] In this embodiment, when the second elastic member 63 is not compressed, the pressure surface 613 of the abutment unit 61 protrudes from the front of the wafer disk, and the abutment surface 611 abuts against the edge of the wafer placement area. When a wafer is placed in the wafer placement area, the abutment surface 611 abuts against the circumferential side wall of the wafer.

[0075] In this embodiment, the crimping assembly 7 includes a crimping unit 71 and a crimping unit mounting seat 72. The crimping unit mounting seat 72 is mounted on the back of the wafer disc. The crimping unit mounting seat 72 is provided with a guide hole for limiting the moving direction of the crimping unit 71. The crimping unit 71 includes a first guide column 715. The first guide column 715 is limited in the guide hole in the crimping unit mounting seat 72. The first elastic member 73 is disposed on the outer surface of the first guide column 715. In this embodiment, the first elastic member 73 is a coil spring for configuring elastic force between the crimping unit 71 and the crimping unit mounting seat 72. The crimping unit 71 includes a crimping surface 712, a curved surface 711 and a guide surface 713. In this embodiment, a hollow area is provided on the wafer disc, and the hollow area enables the crimping unit 71 to reciprocate between the front and back of the wafer disc.

[0076] In this embodiment, the compression drive of the first elastic member 73 is derived from the compression of the guide surface 713 of the crimping unit 71. Specifically, a guide hole 11 is provided on the opposite wafer disk, and the guide hole 11 is spatially aligned with the guide surface 713 of the crimping unit 71 on the opposite wafer disk. When the first stage 1 and the second stage 2 are close to each other, the side wall of the guide hole 11 will contact the guide surface 713 of the opposite crimping unit and apply pressure, forcing the first elastic member 73 to compress.

[0077] In this embodiment, when the first elastic member 73 is not compressed, the crimping surface 712 of the crimping unit 71 is pressed above the wafer placement area, and the arc surface 711 abuts against the edge of the wafer placement area. When a wafer is placed in the wafer placement area, the crimping surface 712 presses the wafer onto the wafer placement area, and the arc surface 711 abuts against the wafer on the circumferential side wall of the wafer.

[0078] In this embodiment, the abutting assembly 6 on the first carrier 1 and the abutting assembly 6 on the second carrier 2 have a spatial alignment, which enables the two pressure-bearing surfaces 613 of the two abutting assemblies 6 to fit together and generate relative pressure when the first carrier 1 and the second carrier 2 are relatively close.

[0079] In this embodiment, the crimping assembly 7 on the first carrier 1 and the crimping assembly 7 on the second carrier 2 have a spatial offset, and the spatial offset enables the two crimping assemblies 7 to be offset from each other and included in the avoidance hole 10 of the opposite wafer disk when the first carrier 1 and the second carrier 2 are relatively close.

[0080] Similarly, in this embodiment, the limiting protrusion 8 on the first carrier 1 and the limiting protrusion 8 on the second carrier 2 have a spatial offset, and the spatial offset enables the limiting protrusions 8 to be offset from each other and included in the avoidance hole of the opposite wafer disk when the first carrier 1 and the second carrier 2 are relatively close.

[0081] In this embodiment, the abutment unit 61 and the crimping unit 71 installed on the first carrier 1 are respectively provided with a second limiting groove 612 and a first limiting groove 714. Correspondingly, a second plunger unit 64 and a first plunger unit 74 are also included. At a certain moment when the abutment unit 61 and the crimping unit 71 move, the plunger of the second plunger unit 64 will be inserted into the second limiting groove 612, and the plunger of the first plunger unit 74 will be inserted into the first limiting groove 714, thereby locking the abutment unit 61 and the crimping unit 71 on the first carrier 1. After the abutment unit 61 and the crimping unit 71 on the first carrier 1 are locked by the corresponding plunger units, the second elastic member 63 and the first elastic member 73 will not be able to drive the abutment unit 61 and the crimping unit 71.

[0082] In this embodiment, double-layer wafer bonding and multi-layer wafer bonding can be performed by using the wafer flip bonding device.

[0083] For details, see Fig.12 In the vacuum chamber 12, the angle between the first stage 1 and the second stage 2 is maintained at 180°, the first wafer plate 4 and the second wafer plate 5 are facing downward, and the first wafer 41 and the second wafer 51 are manually mounted on the first wafer plate 4 and the second wafer plate 5. When mounting the wafers, the pressure surface 613 and the guide surface 713 can be manually pressed, and the pressure surface 613 and the guide surface 713 can be released after the wafers are placed, so that the abutting assembly 6 and the pressing assembly 7 clamp the wafers, so that the first wafer 41 and the second wafer 51 are respectively maintained on the first wafer plate 4 and the second wafer plate 5.

[0084] After the wafers are installed, a vacuum environment is prepared to maintain a certain vacuum degree in the vacuum chamber. Since no cables pass through the vacuum chamber wall, the vacuum degree in the vacuum chamber will remain stable. The surface treatment of the surface to be bonded is performed, including making the first wafer 41 and the second wafer 51 face the activation device 13 at the same time, and activating the surface to be bonded of the first wafer 41 and the second wafer 51 by the activation device 13.

[0085] Flip the second carrier 2 to align the first wafer 41 with the second wafer 51. Introduce a pressure drive device. In this embodiment, the pressure drive device can be a press including a pressure head. The press provides driving force from the back of the second carrier 2 to move the second carrier 2 toward the first carrier 1. During the movement, the pressure surfaces 613 of the abutment units 61 on the first carrier 1 and the second carrier 2 are pressed against each other, and the guide hole 11 and the crimping surface 712 of the opposite crimping unit 71 are pressed against each other, so that the first elastic member 73 and the second elastic member 63 are compressed, and the crimping unit 71 and the abutment unit 61 are respectively away from the wafer placement area. The first wafer 41 loses the circumferential clamping force and falls on the second wafer 51 due to its own weight. The pressure drive device continues to apply pressure to configure a bonding force between the first wafer 41 and the second wafer 51, so that the first wafer 41 and the second wafer 51 are bonded to form a bonding body.

[0086] During the process of the second stage 2 approaching the first stage 1 , the abutting unit 61 and the pressing unit 71 on the first wafer plate 4 are stuck by the second plunger unit 64 and the first plunger unit 74 at a certain moment and lose the ability to reset.

[0087] When the bonding is completed, the second stage 2 moves away from the first stage 1, and the abutting unit 61 and the pressing unit 71 on the second wafer disk 5 are reset by the driving force of the second elastic member 63 and the first elastic member 73, thereby clamping the bonded body on the second wafer disk 5. At this time, since the abutting unit 61 and the pressing unit 71 on the first wafer disk 4 are stuck by the second plunger unit 64 and the first plunger unit 74 at a certain moment and lose the reset ability, no interference occurs.

[0088] The wafer flip bonding device provided in this embodiment can also be used to bond multi-layer wafers. Specifically, after the above-mentioned bonding is completed, the bonding body is kept clamped on the second wafer disk 5, and a new wafer is taken and installed on the first wafer disk 4, so that the new wafer and the bonding body's bonding surfaces are simultaneously facing the activation device 13 for surface activation. After the activation is completed, the above-mentioned bonding process is performed again to obtain a three-layer wafer bonding structure.

[0089] The above steps are repeated to bond multiple layers of wafers until the final product is obtained, and then the product is removed from the second wafer plate 5 to complete the wafer bonding process.

[0090] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. Wafer flip bonding mechanism, characterized in that: include: A first carrier, on which a first wafer plate is disposed, for selectively clamping or releasing a first wafer; A second carrier, on which a second wafer plate is disposed, for selectively clamping a second wafer; A connecting portion, used to connect the first carrier and the second carrier; The first platform and / or the second platform can swing relative to the connecting portion so that the angle between the first platform and the second platform is maintained at 0-180°; When the angle between the first stage and the second stage is maintained at 0°, the first wafer and the second wafer are bonded to form a wafer stack; The wafer stack is clamped by the second wafer disk, and when the angle between the first stage and the second stage is greater than 0°, the position of the wafer stack relative to the second wafer disk remains fixed.

2. The wafer flip bonding mechanism according to claim 1, characterized in that: The first carrier and the second carrier are independently provided with abutment components; The abutment assembly comprises an abutment unit and an abutment unit mounting seat; The abutment unit mounting seat is arranged on the carrier or on the back side of the wafer disc; The abutting unit is elastically guided and connected to the abutting unit mounting seat.

3. The wafer flip bonding mechanism according to claim 2, characterized in that: The abutment unit is configured to have an abutment surface and a pressure-bearing surface; When the pressure-bearing surface is not subjected to force, the abutment unit has a first state; When the pressure-bearing surface is subjected to force, the abutting unit has a second state.

4. The wafer flip bonding mechanism according to claim 3, characterized in that: The first state includes the pressure-bearing surface protruding from the front surface of the wafer disk, and the abutting surface abutting against the circumferential side wall of the wafer; The second state includes the pressure-bearing surface being flush with or recessed in the front surface of the wafer disk, and the abutting surface being away from the circumferential side wall of the wafer.

5. The wafer flip bonding mechanism according to claim 1, characterized in that: The first carrier and the second carrier are independently configured with a crimping assembly; The crimping assembly comprises a crimping unit and a crimping unit mounting seat; The crimping unit mounting seat is arranged on the carrier or on the back of the wafer disc; The crimping unit is elastically guided and connected to the crimping unit mounting seat.

6. The wafer flip bonding mechanism according to claim 5, characterized in that: The crimping unit is configured to have a crimping surface for selectively crimping the wafer onto the wafer tray; A curved surface, for selectively abutting against a circumferential side wall of the wafer; a guide surface for receiving a driving force; When the guide surface does not receive the driving force, the crimping unit has a third state; When the guide surface receives the driving force, the crimping unit has a fourth state.

7. The wafer flip bonding mechanism according to claim 6, characterized in that: The third state includes the pressing surface pressing the wafer onto the wafer tray; The fourth state includes the pressing surface being away from the wafer.

8. The wafer flip bonding mechanism according to claim 2, characterized in that: The abutment unit disposed on the first carrier is provided with a second limiting groove; Also included is a second plunger unit, which is disposed on the first stage or on the back side of the first wafer disc; The second plunger unit cooperates with the second limiting groove to selectively fix the abutment unit on the first carrier.

9. The wafer flip bonding mechanism according to claim 5, characterized in that: The crimping unit disposed on the first carrier is provided with a first limiting groove; It also includes a first plunger unit, which is configured on the first stage or the back side of the first wafer disc; The first plunger unit cooperates with the first limiting groove to selectively clamp the crimping unit on the first carrier.

10. The wafer flip bonding mechanism according to claim 5, characterized in that: The front side of the first wafer disk and the front side of the second wafer disk are independently configured with limiting protrusions, and the limiting protrusions are used to abut against the circumferential side walls of the wafers.

11. The wafer flip bonding mechanism according to claim 10, characterized in that: The first wafer tray and the second wafer tray are independently configured with avoidance holes; The avoidance hole is used to accommodate the limiting protrusion and the pressing unit configured on the opposite wafer disk when the first wafer disk is bonded to the second wafer disk.

12. The wafer flip bonding mechanism according to claim 6, characterized in that: The first wafer plate and the second wafer plate are independently provided with guide holes; When the first wafer disk is bonded to the second wafer disk, the side wall of the guide hole cooperates with the guide surface of the crimping unit arranged on the opposite wafer disk, and a driving force is applied to the guide surface.

13. A wafer bonding method, characterized in that: The wafer flip bonding mechanism according to any one of claims 1 to 12 is used, comprising: Wafer loading: fixing the first wafer and the second wafer on the first wafer plate and the second wafer plate respectively by flip-chip method; the flip-chip method is that the first wafer plate and the second wafer plate face downward; Alignment: flipping the second stage so that the second wafer plate faces the first wafer plate, and aligning the second wafer with the first wafer; after alignment, the first wafer is located above the second wafer, and the vertical distance between the first wafer and the second wafer is less than 1 cm; Bonding: the pressure mechanism applies pressure to the second stage from the back side of the second stage, so that the second stage continues to approach the first stage, forming a bonding force between the first wafer and the second wafer, so that the second wafer is bonded to the first wafer; Reset: the pressure mechanism moves away from the second stage, and the second stage is turned over so that the angle between the second stage and the first stage is greater than 90°; Unloading: removing the bonded body of the first wafer and the second wafer from the second wafer plate.

Images