Wafer counterpoint bonding device and wafer bonding method

Abstract

The invention relates to the technical field of semiconductor material processing, in particular to a wafer alignment bonding device and a wafer bonding method. The wafer alignment bonding device comprises a first carrying table used for carrying a first wafer; the second carrying table is used for carrying a second wafer; the first carrying table and the second carrying table are configured to selectively enable the first wafer and the second wafer to be aligned and attached. According to the wafer counterpoint bonding device, the wafer can be held in the vacuum chamber, the wafer angle can be changed, wafer counterpoint bonding can be carried out, the wafer counterpoint bonding precision can be kept in the process, and the stability of the vacuum degree in the chamber can also be kept. According to the wafer bonding method provided by the invention, double-layer wafer activation bonding and multi-layer wafer activation bonding can be carried out.

Description

Technical Field

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

[0002] In the field of semiconductor material processing, bonding technology can be used to combine two or more materials (or structures) into one, which is an indispensable and important link in the semiconductor manufacturing process. Wafer bonding technology in the bonding field refers to the process of tightly combining two mirror-polished homogeneous or heterogeneous wafers through chemical and physical effects. After the wafers are bonded, the atoms on the interface react under the action of external forces to form covalent bonds to form a whole, and the bonding interface reaches a specific bonding strength.

[0003] Traditional high-temperature wafer bonding methods are no longer suitable for some temperature-sensitive devices or materials with large differences in thermal expansion coefficients. Room temperature surface activation bonding technology can perform bonding at room temperature and can solve the above problems. However, on the one hand, before room temperature surface activation bonding, the bonding surface needs to be processed, and some treatments require the wafer to be placed at a certain angle in the bonding chamber; on the other hand, the room temperature surface activation bonding process requires high vacuum to be maintained in the bonding chamber. This brings difficulties to how to fix and move the wafer in a high vacuum chamber.

[0004] Existing wafer fixing methods include vacuum adsorption, electrostatic adsorption and gluing. Vacuum adsorption cannot be used in a high vacuum bonding chamber. Since the cable of electrostatic adsorption needs to pass through the wall of the bonding chamber, the existence of the cable makes it impossible to continuously maintain the high vacuum degree of the bonding chamber. The problem with gluing is that during the step of activating the wafer surface, it will cause colloid splashing and contaminate the chamber; the uniformity of glue coating will also affect the uniformity of pressure distribution on the bonding interface during bonding.

[0005] Therefore, it is necessary to provide a wafer bonding device and a wafer bonding method to solve the above problems. Summary of the invention

[0006] The purpose of the present invention is to provide a wafer alignment bonding device, which can hold a wafer in a vacuum chamber, change the wafer angle, and perform wafer alignment bonding, and in the process, both the wafer alignment accuracy and the vacuum degree in the chamber can be maintained. A wafer bonding method is provided to perform double-layer wafer activation bonding and multi-layer wafer activation bonding.

[0007] To achieve this object, the present invention adopts the following technical solutions:

[0008] A wafer alignment bonding device comprises: a first carrier, used for carrying a first wafer;

[0009] A second carrier, used for carrying a second wafer;

[0010] The first stage and the second stage are configured to selectively align and bond the first wafer to the second wafer;

[0011] The first carrier is provided with at least two first positioning components and at least one first pressure positioning component;

[0012] Each of the first positioning components and each of the first pressure positioning components is provided with at least one positioning column;

[0013] The first positioning assembly and the first pressure positioning assembly are arranged in the circumferential direction of the first wafer carrying area, so that the positioning column selectively abuts against the circumferential side wall of the first wafer, and a first pressure is selectively arranged between the positioning column and the circumferential side wall of the first wafer;

[0014] The connecting line of the positioning columns on the first positioning assembly and the first pressure positioning assembly is roughly in the shape of a triangle, so that a triangular positioning can be formed in the circumferential direction of the first wafer, which is conducive to stably fixing the first wafer;

[0015] The second carrier is provided with at least two second positioning components and at least one second pressure positioning component;

[0016] Each of the second positioning assembly and the second pressure positioning assembly is provided with at least one positioning column;

[0017] The second positioning assembly and the second pressure positioning assembly are arranged in the circumferential direction of the second wafer carrying area, so that the positioning column selectively abuts against the circumferential side wall of the second wafer, and a second pressure is selectively arranged between the positioning column and the circumferential side wall of the second wafer;

[0018] The connecting line of the positioning columns on the second positioning assembly and the second pressure positioning assembly is roughly in the shape of a triangle, so that a triangular positioning can be formed in the circumferential direction of the second wafer, which is conducive to stably fixing the second wafer;

[0019] The first pressure and the second pressure are independently 10-50N.

[0020] A certain pressure is configured between the circumferential side walls of the first wafer and the second wafer and the positioning column through the first pressure positioning component and the second pressure positioning component. When the angle of the carrier is adjusted, the swing of the carrier will not cause the wafer to move. When the chamber is evacuated, the pressure difference between the upper and lower surfaces of the wafer caused by the rapid change of air pressure will not cause the wafer to move. When the wafer surface is activated, the bombardment of the wafer surface will not cause the wafer to move. However, if the configured pressure is too large, due to the thin wafer, the excessive pressure will cause the wafer to warp, which will affect the uniformity of the wafer surface activation and the uniformity of the distribution of the bonding force of the bonding interface during subsequent bonding.

[0021] Furthermore, the first platform and the second platform are connected by a hinge;

[0022] The first carrier and the second carrier can be flipped relative to each other so that the angle between the first wafer and the second wafer is maintained between 0-180°.

[0023] Furthermore, the positioning column on the first positioning assembly is disposed through the table surface of the first carrier, and is configured to selectively extend out of or retract into the table surface of the first carrier;

[0024] The positioning column on the first pressure positioning assembly selectively moves in a direction parallel to the surface of the first stage, and is configured to selectively extend out of or retract into the surface of the first stage;

[0025] An avoidance hole is arranged on the surface of the first carrier, or when the positioning columns on the first positioning component and the first pressure positioning component are retracted into the surface of the first carrier, an avoidance hole is formed on the surface of the first carrier.

[0026] Furthermore, the second positioning assembly includes at least one positioning column, and the positioning column on the second positioning assembly is fixed in a direction perpendicular to the second stage surface, that is, it will not expand or contract relative to the second stage surface;

[0027] The positioning column on the second pressure positioning assembly selectively moves in a direction parallel to the second stage surface.

[0028] Furthermore, the second carrier is provided with a receiving cavity;

[0029] The second pressure positioning assembly is disposed in the accommodating cavity;

[0030] The second pressure positioning assembly includes a second slider;

[0031] A second elastic member is provided between the second sliding block and the side wall of the accommodating cavity;

[0032] The second elastic member applies pressure directed toward the second wafer supporting area to the second slider;

[0033] The positioning column on the second pressure positioning assembly is configured on the second sliding block.

[0034] Furthermore, the second pressure positioning assembly includes a lever, and the lever is disposed between the second slider and the second wafer supporting area;

[0035] When the lever is driven, the lever presses the second slider, the second elastic member is compressed, and the second slider moves away from the second wafer carrying area;

[0036] When the driving of the lever stops, the second elastic member is released, so that the second slider presses the lever, and the second slider moves together with the lever toward the second wafer carrying area.

[0037] Furthermore, it also includes a touch-pressure assembly, which is disposed in the accommodating cavity and is used to drive the lever;

[0038] The touch pressure component is configured to move in a direction perpendicular to the second stage surface

[0039] Preferably, an elastic return member is arranged between the touch-pressure assembly and the second carrier, and when the touch-pressure assembly is not touched or pressed, the elastic return member enables the touch-pressure assembly to maintain an initial position;

[0040] The touch-pressure component is provided with an inclined surface tangent to the lever. When the touch-pressure component is moved by touch-pressure, the inclined surface presses the lever, so that the lever presses the second slider. The pressing includes direct pressing or indirect pressing.

[0041] Furthermore, a pressing assembly is disposed on the first carrier, and the pressing assembly includes a protruding unit protruding from the surface of the first carrier;

[0042] The pressing component is configured to use the protruding unit to press the touch-pressing component on the second stage during the alignment and bonding process between the first stage and the second stage, so as to move the touch-pressing component.

[0043] Furthermore, the first positioning assembly includes a fixing seat and a magnetic seat provided on the first carrier body;

[0044] It also includes a mounting seat, one end of which is mounted on the fixing seat through a first elastic member;

[0045] The mounting seat is provided with a magnet, and the magnet is arranged corresponding to the magnetic seat;

[0046] The positioning column is installed at the other end of the mounting seat.

[0047] The wafer bonding method is performed using the above-mentioned wafer bonding device, comprising:

[0048] Loading: installing the first wafer and the second wafer on the first stage and the second stage respectively, applying pulling force to the first pressure positioning assembly and the second pressure positioning assembly before loading, so that the first pressure positioning assembly and the second pressure positioning assembly are respectively away from the bearing areas of the first wafer and the second wafer; after placing the first wafer and the second wafer in a fixed position, releasing the pulling force, so that the first pressure positioning assembly and the second pressure positioning assembly squeeze the first wafer and the second wafer respectively, and generating pressure between the first wafer and the first positioning assembly, and between the second wafer and the second positioning assembly; the pressure is maintained at 10-50N;

[0049] Activation: adjusting the angle between the first stage and the second stage so that the angle between the first wafer and the second wafer is maintained between 0° and 180°, so that the first wafer and the second wafer face the activation device for surface activation;

[0050] Pre-alignment: the first stage is located above the second stage, a driving force is applied to the first stage and / or the second stage, the first stage and the second stage move toward each other, the second positioning component presses the first positioning component, or the second stage surface presses the first positioning component, the first positioning component is retracted into the first stage surface, and at the same time (referring to approximately the same time period), the protruding unit on the first stage presses the touch pressure component on the second stage, the second pressure positioning component is away from the second wafer carrying area, the first wafer is separated from the first stage and falls on the second wafer, forming a wafer stack; at this time, there is no external pressure between the first wafer and the second wafer;

[0051] Alignment: moving the first stage and the second stage away from each other, making the protrusion unit on the first stage leave the contact pressure component of the second stage, and making the second pressure positioning component apply pressure to the side wall of the wafer stack, so that the first wafer and the second wafer are concentrically stacked;

[0052] Bonding: The first carrier and the second carrier are moved toward each other and bonded together, and external pressure is applied to bond the first wafer and the second wafer to form a bonded body.

[0053] The above-mentioned “selective” is understood to mean different states presented when the corresponding structure is driven by external force.

[0054] Beneficial effects of the present invention:

[0055] On the one hand, the present invention proposes a wafer alignment bonding device, which configures a certain pressure between the circumferential side walls of the first wafer and the second wafer and the positioning column through a pressure positioning component. When the angle of the carrier is adjusted, the swing of the carrier will not cause the wafer to move. When the chamber is evacuated, the pressure difference between the upper and lower surfaces of the wafer caused by the rapid change of air pressure will not cause the wafer to move. When the wafer surface is activated, the bombardment of the wafer surface will not cause the wafer to move.

[0056] On the other hand, the wafer alignment bonding device of the present invention is located in a vacuum chamber and has a purely mechanical structure. The driving part is connected to the side wall of the chamber using magnetic fluid or metal bellows. No cables penetrate into the side wall of the chamber, which will not affect the vacuum degree of the chamber.

[0057] On the other hand, the first carrier and the second carrier of the present application can perform relative folding bonding of 0-180°, which can not only perform bonding of double-layer wafers, but also bonding of multi-layer wafers.

[0058] The wafer alignment and bonding device provided in the present application can hold the wafer in a vacuum chamber, change the wafer angle, and perform wafer alignment and bonding. During the process, it can maintain the wafer position accuracy and alignment and bonding accuracy, and also maintain the vacuum degree in the chamber stable. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Figure 1 It is a schematic structural diagram of a wafer alignment bonding device of the present invention;

[0060] Figure 2 It is a schematic diagram of a first viewing angle of the first stage of the wafer alignment bonding device of the present invention;

[0061] Figure 3 It is a schematic diagram of the second viewing angle of the first stage of the wafer alignment bonding device of the present invention;

[0062] Figure 4 It is a schematic diagram of the second stage of the wafer alignment bonding device of the present invention from a first viewing angle;

[0063] Figure 5 It is a schematic diagram of the second viewing angle of the second stage of the wafer alignment bonding device of the present invention;

[0064] Figure 6 It is a schematic diagram of wafer activation of the wafer alignment bonding device of the present invention;

[0065] Figure 7 It is a schematic diagram of wafer bonding of the wafer alignment bonding device of the present invention;

[0066] In the figure: 1. first carrier; 11. first wafer; 12. positioning column; 13. magnet; 14. first elastic member; 141. second elastic member; 142. third elastic member; 15. first slider; 16. fixing seat; 17. protruding unit; 18. mounting seat; 19. magnetic seat; 2. second carrier; 21. second wafer; 22. touch-pressure assembly; 23. lever; 24. second slider; 3. hinged portion; 4. pressurizing portion; 5. vacuum chamber; 6. activation device. DETAILED DESCRIPTION

[0067] 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.

[0068] 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.

[0069] In the present invention, unless otherwise clearly specified and limited, the first feature "above" or "below" the second feature may include the first and second features directly contacting, or may include the first and second features not directly contacting but contacting through another feature between them. Moreover, the first feature "above", "above" and "above" the second feature include the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. The first feature "below", "below" and "below" the second feature include the first feature being directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature. In the description of this embodiment, the terms "above", "below", "right", etc., orientation or positional relationship are based on the orientation or positional relationship shown in the drawings, 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 orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of 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 1-7The embodiment of the present application provides a wafer alignment bonding device, which is used to fix, activate and align wafers in a vacuum environment in a vacuum chamber. The wafer alignment bonding device includes a vacuum chamber 5, and a first carrier 1 for carrying a first wafer 11 and a second carrier 2 for carrying a second wafer 21 located in the vacuum chamber 5. The first carrier 1 and the second carrier 2 are connected by a hinge 3.

[0071] In this embodiment, the hinged portion 3 is a rotating shaft, and the rotating shaft is configured to have a driving force, and the driving force can drive the first stage 1 and the second stage 2 to perform relative folding movement, so that the angle between the first stage 1 and the second stage 2 is maintained between 0-180°. The power source for driving the rotating shaft is placed outside the vacuum chamber 5, and the rotating shaft and the power source are connected through a magnetic fluid sealing device. There is no cable passing through the side wall of the vacuum chamber 5, so that the vacuum degree in the vacuum chamber 5 can always be maintained stable, which is conducive to improving the surface treatment effect and bonding quality of the wafer.

[0072] Under the connection and drive of the hinge 3, the first stage 1 and the second stage 2 can maintain an angle of 0-180° according to the process requirements. For example, in one embodiment, when the surfaces to be bonded of the first wafer 11 and the second wafer 21 are activated at the same time, the angle between the first stage 1 and the second stage 2 can be maintained at 180°, so that the first wafer 11 and the second wafer 21 face the activation device 6 at the same time, so that the surfaces to be bonded of the first wafer 11 and the second wafer 21 can be activated synchronously. Figure 6 As shown, in one embodiment, in order to reduce the impurities generated in the vacuum chamber 5 during activation and fall on the surfaces of the first wafer 11 and the second wafer 21, an inverted manner can be used for activation. At this time, the angle between the first stage 1 and the second stage 2 is 180°, the first stage 1 and the second stage 2 are located at the upper part of the vacuum chamber 5, the activation device 6 is located at the lower part of the vacuum chamber 5, and the surfaces to be bonded of the first wafer 11 and the second wafer 21 face downward, thereby reducing the impurities falling on the surfaces to be bonded of the first wafer 11 and the second wafer 21.

[0073] Since the present application is provided with positioning components on the first carrier 1 and the second carrier 2, when performing the above-mentioned inversion activation process, the first wafer 11 and the second wafer 21 can still be maintained on the wafer carrying areas of the first carrier 1 and the second carrier 2 without positional displacement.

[0074] Specifically, in the present embodiment, two first positioning components and a first pressure positioning component are arranged on the first carrier 1. The first positioning component includes a fixed seat 16 and a magnetic seat 19 installed on the first carrier 1. In a feasible embodiment, the fixed seat 16 and the magnetic seat 19 can be configured as an integrated magnetic fixed seat, that is, the fixed seat 16 and the magnetic seat 19 have the same structure. It also includes a mounting seat 18, which is mounted on the fixed seat 16 through a first elastic member 14. A positioning column 12 is installed at the other end of the mounting seat 18. A magnet 13 is also installed on the mounting seat 18, and the position of the magnet 13 is opposite to the position of the magnetic seat 19. In the present embodiment, the first elastic member 14 is a coil spring. When the first positioning component is not subjected to external force, the mounting seat 18 and the fixed seat 16 are supported by a coil spring, so that the magnet 13 on the mounting seat 18 and the magnetic seat 19 maintain a certain distance. In this state, the positioning column 12 extends out of the table surface of the first carrier 1.

[0075] When the positioning column 12 on the mounting seat 18 is squeezed, the first elastic member 14 is compressed. When the magnetic attraction force between the magnet 13 on the mounting seat 18 and the magnetic seat 19 is greater than the elastic force of the first elastic member 14, the magnet 13 is adsorbed on the magnetic seat 19, the first elastic member 14 is compressed, and the positioning column 12 is retracted into the surface of the first carrier 1.

[0076] The fixing seat 16 is provided with a through hole, which is connected to the back side of the first carrier 1. When a plug-in is inserted into the through hole from the back side of the first carrier 1, the magnet 13 and the magnetic seat 19 that have been adsorbed together can be separated.

[0077] The first pressure positioning assembly includes a fixing seat 16 and a magnetic seat 19 mounted on the first carrier 1, and also includes a first slider 15. The first slider 15 is mounted on the fixing seat 16 through a first elastic member 14. A positioning column 12 is mounted on the other end of the first slider 15. A magnet 13 is also mounted on the first slider 15. The position of the magnet 13 is opposite to the position of the magnetic seat 19. A third elastic member 142 is provided between the first slider 15 and the first carrier 1. The third elastic member 142 provides a pressure directed to the first wafer bearing area to the first slider 15.

[0078] When the first wafer 11 is a trimmed wafer, the number of the positioning posts 12 on the first slider 15 may be two, and the two positioning posts 12 can firmly clamp the trimmed edge of the first wafer 11 .

[0079] When it is necessary to fix the first wafer 11, the first slider 15 is first driven away from the first wafer 11 placement area by external force. After the first wafer 11 is placed, the first slider 15 is released. The first slider 15 moves toward the first wafer 11 supporting area under the elastic force of the third elastic member 142. The positioning column 12 located on the first positioning assembly and the first pressure positioning assembly is clamped on the side wall of the first wafer 11 to fix the first wafer 11.

[0080] In this embodiment, two second positioning components and a second pressure positioning component are arranged on the second stage 2. The second positioning component includes a positioning column 12 fixed on the second stage 2. The second stage 2 is provided with a receiving cavity, and the second pressure positioning component is arranged in the receiving cavity. The second pressure positioning component includes a second slider 24. A second elastic member 141 is arranged between the second slider 24 and the side wall of the receiving cavity. The second elastic member 141 applies pressure directed to the bearing area of ​​the second wafer 21 to the second slider 24. Two positioning columns are arranged on the second slider 24. The second pressure positioning component includes a lever 23, and the lever 23 is arranged between the second slider 24 and the bearing area of ​​the second wafer 21. When the lever 23 is driven, the lever 23 squeezes the second slider 24, and the second elastic member 141 is compressed, so that the second slider 24 is away from the bearing area of ​​the second wafer 21. When the lever 23 is stopped, the second elastic member 141 is released. Driven by the elastic force of the second elastic member 141, the second slider 24 squeezes the lever 23, so that the second slider 24 and the lever 23 move toward the bearing area of ​​the second wafer 21.

[0081] In this embodiment, a touch-pressure assembly 22 is further included. The touch-pressure assembly 22 is disposed in the accommodating cavity and is used to drive the lever 23. The touch-pressure assembly 22 is configured to move in a direction perpendicular to the surface of the second stage 2. In this embodiment, an elastic reset member is disposed between the touch-pressure assembly 22 and the second stage 2. When the touch-pressure assembly 22 is not touched, the elastic reset member is elastically released to keep the touch-pressure assembly 22 in its initial position. The touch-pressure assembly 22 is configured with an inclined surface tangent to the lever 23. When the touch-pressure assembly 22 is touched and moved, the inclined surface squeezes the lever 23. The lever 23 moves along the inclined surface and squeezes the second slider 24. At the same time, the second slider 24 compresses the second elastic member 141 and moves toward the second elastic member 141.

[0082] In a preferred embodiment, the touch-pressure assembly 22 is configured into two groups, and the two groups of touch-pressure assembly 22 are configured at both ends of the lever 23, so that the lever 23 can be evenly stressed. In this embodiment, the touch-pressure assembly 22 is in direct contact with the lever 23. In other feasible embodiments, the touch-pressure assembly 22 and the lever 23 can also be connected by other structures, in short, it can be achieved that the lever 23 can move when the touch-pressure assembly 22 is touched and pressed.

[0083] In the present embodiment, the structure for touching and pressing the touch-pressing component 22 is a pressing component arranged on the first carrier 1, and the pressing component includes a protruding unit 17 protruding from the surface of the first carrier 1. During the alignment and bonding process between the first carrier 1 and the second carrier 2, the protruding unit 17 touches and presses the touch-pressing component 22 on the second carrier 2, so that the touch-pressing component 22 moves.

[0084] The present embodiment provides a wafer bonding method, including wafer loading: mounting a first wafer 11 and a second wafer 21 on a first stage 1 and a second stage 2, respectively. Before wafer loading, a pulling force is applied to the first pressure positioning assembly and the second pressure positioning assembly, so that the first pressure positioning assembly and the second pressure positioning assembly are respectively away from the bearing area of ​​the first wafer 11 and the second wafer 21. After the first wafer 11 and the second wafer 21 are placed in the bearing area, the pulling force is released, so that the first pressure positioning assembly and the second pressure positioning assembly squeeze the first wafer 11 and the second wafer 21, respectively, and a pressure of 10-50N is generated between the first wafer 11 and the first positioning assembly, and between the second wafer 21 and the second positioning assembly. Under the action of this pressure, when the angle of the stage is adjusted, the swing of the stage will not cause the wafer to move. When the chamber is evacuated, the pressure difference generated by the rapid change of air pressure on the upper and lower sides of the wafer will not cause the wafer to move. When the wafer surface is activated, the bombardment of the wafer surface will not cause the wafer to move. However, if the configured pressure is too large, due to the thin wafer, excessive pressure will cause the wafer to warp, which will affect the uniformity of wafer surface activation and the uniformity of distribution of bonding force at the bonding interface during subsequent bonding.

[0085] Activation: adjusting the angle between the first stage 1 and the second stage 2 so that the angle between the first wafer 11 and the second wafer 21 is maintained at 180°, so that the first wafer 11 and the second wafer 21 face the activation device 6 for surface activation;

[0086] Pre-alignment: The first stage 1 is positioned above the second stage 2, and a driving force is applied to move the first stage 1 and the second stage 2 toward each other, so that the positioning columns on the second positioning assembly and the second pressure positioning assembly squeeze the positioning columns on the first positioning assembly and the first pressure positioning assembly, and the positioning columns on the first positioning assembly and the first pressure positioning assembly are retracted into the table surface of the first stage 1 due to the attraction of the magnetic seat 19 and the magnet 13. The first wafer 11 detaches from the first stage 1 under the action of its own weight due to the lack of circumferential pressure. At the same time, the protruding unit 17 on the first stage 1 squeezes the touch-pressure assembly 22 on the second stage 2, so that the second slider 24 is away from the wafer bearing area, leaving space for the first wafer 11 to fall in. With the mutual cooperation between the first stage 1 and the second stage 2, the first wafer 11 falls on the second wafer 21 to form a superposition body. At this time, the first wafer 11 only falls on the second wafer 21, and there is no other external force between the two.

[0087] Alignment: After the first wafer 11 falls on the second wafer 21, it may drift during the falling process, resulting in the first wafer 11 and the second wafer 21 being non-concentric, so it is necessary to align the first wafer 11 and the second wafer 21 concentrically. The first stage 1 and the second stage 2 are moved in opposite directions, so that the protruding unit 17 on the first stage 1 leaves the contact pressure component 22 of the second stage 2, and the second elastic component 141 is released, driving the second slider 24 to move toward the bearing area of ​​the second wafer 21. The positioning column on the second slider 24 applies pressure to the side wall of the stack of the first wafer 11 and the second wafer 21 again, so that the first wafer 11 and the second wafer 21 are concentrically stacked.

[0088] Bonding: The first carrier 1 and the second carrier 2 are moved toward each other and bonded, and external pressure is applied to bond the first wafer 11 and the second wafer 21 to form a bonded body.

[0089] The embodiment of the present application also includes multi-layer wafer bonding, where the bonded body formed by the first wafer 11 and the second wafer 21 is used as a new second wafer. A wafer is taken and used as a new first wafer, and the bonding steps of the double-layer wafer are repeated to perform multi-layer wafer bonding.

[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. A wafer alignment bonding device, characterized in that: include: A first carrier, used for carrying a first wafer; A second carrier, used for carrying a second wafer; The first stage and the second stage are configured to selectively align and bond the first wafer to the second wafer; The first carrier is provided with at least two first positioning components and at least one first pressure positioning component; Each of the first positioning assembly and the first pressure positioning assembly is provided with at least one positioning column; The first positioning assembly and the first pressure positioning assembly are arranged in the circumferential direction of the first wafer carrying area, so that the positioning column selectively abuts against the circumferential side wall of the first wafer, and a first pressure is selectively arranged between the positioning column and the circumferential side wall of the first wafer; The second carrier is provided with at least two second positioning components and at least one second pressure positioning component; Each of the second positioning assembly and the second pressure positioning assembly is provided with at least one positioning column; The second positioning assembly and the second pressure positioning assembly are arranged in the circumferential direction of the second wafer carrying area, so that the positioning column selectively abuts against the circumferential side wall of the second wafer, and a second pressure is selectively arranged between the positioning column and the circumferential side wall of the second wafer; The first pressure and the second pressure are independently 10-50N.

2. The wafer alignment bonding device according to claim 1, characterized in that: The first platform and the second platform are connected by a hinge; The first carrier and the second carrier can be flipped relative to each other so that the angle between the first wafer and the second wafer is maintained between 0-180°.

3. The wafer alignment bonding device according to claim 1, characterized in that: The positioning column on the first positioning assembly is disposed through the table surface of the first carrier and is configured to selectively extend out of or retract into the table surface of the first carrier; The positioning column on the first pressure positioning assembly selectively moves in a direction parallel to the surface of the first stage, and is configured to selectively extend out of or retract into the surface of the first stage; An avoidance hole is arranged on the surface of the first carrier, or when the positioning columns on the first positioning component and the first pressure positioning component are retracted into the surface of the first carrier, an avoidance hole is formed on the surface of the first carrier.

4. The wafer alignment bonding device according to claim 1, characterized in that: The second positioning assembly includes at least one positioning column, and the positioning column on the second positioning assembly is fixed in a direction perpendicular to the second stage surface; The positioning column on the second pressure positioning assembly selectively moves in a direction parallel to the second stage surface.

5. The wafer alignment bonding device according to claim 4, characterized in that: The second carrier is provided with a receiving cavity; The second pressure positioning assembly is disposed in the accommodating cavity; The second pressure positioning assembly includes a second slider; A second elastic member is provided between the second sliding block and the side wall of the accommodating cavity; The second elastic member applies pressure directed toward the second wafer supporting area to the second slider; The positioning column on the second pressure positioning assembly is configured on the second sliding block.

6. The wafer alignment bonding device according to claim 5, characterized in that: The second pressure positioning assembly includes a lever, and the lever is disposed between the second slider and the second wafer carrying area; When the lever is driven, the lever presses the second slider, the second elastic member is compressed, and the second slider moves away from the second wafer carrying area; When the driving of the lever stops, the second elastic member is released, so that the second slider presses the lever, and the second slider moves together with the lever toward the second wafer carrying area.

7. The wafer alignment bonding device according to claim 6, characterized in that: It also includes a touch-pressure assembly, which is disposed in the accommodating cavity and is used to drive the lever; The touch-pressure component is provided with an inclined surface tangent to the lever. When the touch-pressure component is moved by touch-pressure, the inclined surface presses the lever, so that the lever presses the second sliding block.

8. The wafer alignment bonding device according to claim 7, characterized in that: The first carrier is provided with a pressing assembly, and the pressing assembly comprises a protruding unit protruding from the surface of the first carrier; The pressing component is configured to use the protruding unit to press the touch-pressing component on the second stage during the alignment and bonding process between the first stage and the second stage, so as to move the touch-pressing component.

9. The wafer alignment bonding device according to claim 3, characterized in that: The first positioning assembly includes a fixing seat and a magnetic seat provided on the first carrier body; It also includes a mounting seat, one end of which is mounted on the fixing seat through a first elastic member; The mounting seat is provided with a magnet, and the magnet is arranged corresponding to the magnetic seat; The positioning column is installed at the other end of the mounting seat.

10. A wafer bonding method, characterized in that: The wafer alignment bonding device according to any one of claims 1 to 9 is used, comprising: Loading: installing the first wafer and the second wafer on the first stage and the second stage respectively, applying pulling force to the first pressure positioning assembly and the second pressure positioning assembly before loading, so that the first pressure positioning assembly and the second pressure positioning assembly are respectively away from the bearing areas of the first wafer and the second wafer; after placing the first wafer and the second wafer in a fixed position, releasing the pulling force, so that the first pressure positioning assembly and the second pressure positioning assembly squeeze the first wafer and the second wafer respectively, and generating pressure between the first wafer and the first positioning assembly, and between the second wafer and the second positioning assembly; the pressure is maintained at 10-50N; Activation: adjusting the angle between the first stage and the second stage so that the angle between the first wafer and the second wafer is maintained between 0° and 180°, so that the first wafer and the second wafer face the activation device for surface activation; Pre-alignment: locate the first stage above the second stage, apply driving force to the first stage and / or the second stage, move the first stage and the second stage toward each other, make the second positioning component squeeze the first positioning component, or make the second stage surface squeeze the first positioning component, retract the first positioning component into the first stage surface, and at the same time make the protruding unit on the first stage squeeze the touch pressure component on the second stage, make the second pressure positioning component away from the second wafer carrying area, make the first wafer detach from the first stage and fall on the second wafer, so as to form a wafer stack; Alignment: moving the first stage and the second stage away from each other, making the protrusion unit on the first stage leave the contact pressure component of the second stage, and making the second pressure positioning component apply pressure to the side wall of the wafer stack, so that the first wafer and the second wafer are concentrically stacked; Bonding: The first carrier and the second carrier are moved toward each other and bonded together, and external pressure is applied to bond the first wafer and the second wafer to form a bonded body.

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