Wafer bonding device

Abstract

The invention provides a wafer bonding device. The wafer bonding device comprises a bonding chamber, and a first carrying disc, a second carrying disc, a driving assembly, a sputtering assembly and a wafer alignment assembly which are located in the bonding chamber. The first carrying disc comprises a first carrying surface used for fixing a wafer, the second carrying disc comprises a second carrying surface used for fixing the wafer, the first carrying surface and the second carrying surface are oppositely arranged, the driving assembly comprises a first driving part, and the first driving part is used for driving the first carrying disc and / or the second carrying disc to move; and bonding the wafer fixed on the first bearing surface with the wafer fixed on the second bearing surface. And the sputtering assembly is used for depositing a bonding material on the surface of the wafer fixed by the first bearing surface and the surface of the wafer fixed by the second bearing surface. The wafer alignment assembly is used for aligning the wafer fixed by the first bearing surface with the wafer fixed by the second bearing surface. According to the wafer bonding device, wafer sputtering and wafer alignment are carried out in the bonding chamber, the wafer bonding quality is improved, and the production efficiency is improved.

Description

Technical Field

[0001] The present application relates to the field of semiconductor manufacturing technology, and in particular to a wafer bonding device. Background Art

[0002] Wafer bonding equipment is a special device used to tightly bond wafers and is widely used in semiconductor manufacturing, microelectronics, micro-electromechanical systems and other fields. In order to enhance the strength of wafer bonding and improve the reliability and stability of bonding, alignment and bonding can be performed after a metal layer is sputtered on the surface of the wafer.

[0003] In the existing wafer bonding process, bonding materials are first deposited on the surfaces of two wafers and the two wafers are aligned outside the bonding chamber, and then the wafers are transferred to the bonding chamber for bonding. Since the bonding materials on the surfaces of the wafers are easily oxidized during the transfer process, the positions of the two wafers may shift, resulting in reduced bonding accuracy and quality. Summary of the invention

[0004] The present application provides a wafer bonding device. The wafer bonding device comprises a bonding chamber, and a first carrier, a second carrier, a driving component, a sputtering component and a wafer alignment component located in the bonding chamber;

[0005] The first carrier includes a first carrying surface for fixing the wafer; the second carrier includes a second carrying surface for fixing the wafer, and the first carrying surface is arranged opposite to the second carrying surface; the driving assembly includes a first driving part, and the first driving part is used to drive the first carrier and / or the second carrier to move, so that the wafer fixed on the first carrying surface is bonded with the wafer fixed on the second carrying surface;

[0006] The sputtering assembly is used to deposit bonding material onto the surface of the wafer fixed to the first carrying surface and the surface of the wafer fixed to the second carrying surface;

[0007] The wafer alignment assembly is used to align the wafer fixed on the first carrying surface with the wafer fixed on the second carrying surface.

[0008] In one embodiment, the first carrying surface and the second carrying surface are arranged along a vertical direction, and the sputtering assembly is located above the first carrier and the second carrier.

[0009] In one embodiment, the driving assembly further includes a second driving unit; the second driving unit is connected to the first carrier plate, driving the first carrier plate to rotate in a direction perpendicular to the first carrying surface; and / or

[0010] The driving assembly further includes a third driving unit; the third driving unit is connected to the second carrier plate and drives the second carrier plate to rotate in a direction perpendicular to the second carrying surface.

[0011] In one embodiment, the wafer bonding device also includes a controller, and the wafer alignment assembly includes an image sensor and a fourth drive unit, the image sensor is used to determine first relative position information between the wafer fixed on the first carrying surface and the first carrying surface, and second relative position information between the wafer fixed on the second carrying surface and the second carrying surface; the fourth drive unit is connected to the first carrier and / or the second carrier, and the controller is used to control the fourth drive unit to drive the carrier connected thereto to move according to the first relative position information and the second relative position information.

[0012] In one embodiment, the image sensor of the wafer alignment assembly includes a first image sensor group arranged on the side of the first carrier and a second image sensor group arranged on the side of the second carrier; the first image sensor group and the second image sensor group respectively include at least two image sensors; the second image sensor group is used to detect first relative position information, the first relative position information at least includes a first distance, a second distance and a first angle; the first image sensor group is used to detect second relative position information, the second relative position information at least includes a third distance, a fourth distance and a second angle;

[0013] The first distance is the distance between the first intersection and the second intersection in the first direction, and the second distance is the distance between the third intersection and the fourth intersection in the second direction; the first intersection is the intersection of a straight line passing through the center of the first carrying surface and extending along the first direction and an edge of the first carrying surface; the second intersection is the intersection of a straight line passing through the center of the wafer fixed on the first carrying surface and extending along the first direction and an edge of the wafer; the third intersection is the intersection of a straight line passing through the center of the first carrying surface and extending along the second direction and an edge of the first carrying surface; The four intersection points are the intersection points of a straight line passing through the center of the wafer fixed on the first supporting surface and extending along the second direction and the edge of the wafer; the first intersection point and the second intersection point are located on the same side of the center of the first supporting surface, and the third intersection point and the fourth intersection point are located on the same side of the center of the first supporting surface; the first angle is the angle between a first connecting line and a straight line extending along the second direction and passing through the center of the wafer fixed on the first supporting surface, and the first connecting line is a connecting line between the cut of the wafer fixed on the first supporting surface and the center of the wafer; the first direction is perpendicular to the second direction;

[0014] The third distance is the distance between the fifth intersection and the sixth intersection in the first direction, and the fourth distance is the distance between the seventh intersection and the eighth intersection in the second direction; the fifth intersection is the intersection of a straight line passing through the center of the second bearing surface and extending along the first direction and an edge of the second bearing surface; the sixth intersection is the intersection of a straight line passing through the center of the wafer fixed on the second bearing surface and extending along the first direction and an edge of the wafer; the seventh intersection is the intersection of a straight line passing through the center of the second bearing surface and extending along the second direction and an edge of the second bearing surface. The eighth intersection is the intersection of a straight line passing through the center of the wafer fixed on the second carrying surface and extending along the second direction and the edge of the wafer; the fifth intersection and the sixth intersection are located on the same side of the center of the second carrying surface, and the seventh intersection and the eighth intersection are located on the same side of the center of the second carrying surface; the second angle is the angle between the second connecting line and a straight line extending along the second direction and passing through the center of the wafer fixed on the second carrying surface; the second connecting line is a line connecting the cutout of the wafer fixed on the second carrying surface and the center of the wafer;

[0015] The controller first controls the fourth driving unit to drive the carrier connected to it to rotate according to the difference between the first angle and the second angle, and then controls the fourth driving unit to drive the carrier connected to it to move a distance in the first direction that is the difference between the first distance and the third distance, and a distance in the second direction that is the difference between the second distance and the fourth distance.

[0016] In one embodiment, the fourth distance and the second angle are detected by the same image sensor of the first image sensor group; or, the third distance, the fourth distance and the second angle are respectively detected by different image sensors of the first image sensor group.

[0017] In one embodiment, the second distance and the first angle are detected by the same image sensor of the second image sensor group; or, the first distance, the second distance and the first angle are respectively detected by different image sensors of the second image sensor group.

[0018] In one embodiment, the fourth driving part includes a first lead screw, a first motor, a second lead screw, a second motor and a rotating part; the first lead screw extends along the first direction, and the second lead screw extends along the second direction; the controller controls the motor to drive the carrier connected to the fourth driving part to move along the first lead screw or the second lead screw, and also controls the rotating part to drive the carrier connected to it to rotate in a direction perpendicular to its bearing surface.

[0019] In one embodiment, the driving assembly further includes a second driving unit; the second driving unit is connected to the first carrier plate, driving the first carrier plate to rotate in a direction perpendicular to the first bearing surface; when the fourth driving unit is drivingly connected to the first carrier plate, the second driving unit is reused as the fourth driving unit; and / or,

[0020] The driving assembly also includes a third driving unit; the third driving unit is connected to the second carrier plate to drive the second carrier plate to rotate in a direction perpendicular to the second bearing surface; when the fourth driving unit is drivingly connected to the second carrier plate, the third driving unit is reused as the fourth driving unit.

[0021] In one embodiment, the wafer bonding device also includes a controller; the wafer alignment assembly also includes multiple distance sensors and a leveling structure; the controller is used to control the leveling structure according to the distances detected by the multiple distance sensors so that the distances detected by each distance sensor are the same.

[0022] In one embodiment, the wafer bonding apparatus further comprises a first carrier for arranging the first carrier, and a second carrier for arranging the second carrier;

[0023] The first stage includes a first plane, the second stage includes a second plane opposite to the first plane, the first carrier is fixed on the first plane, and the second carrier is fixed on the second plane; the distance sensor is arranged on the first plane or the second plane, and is used to detect the distance between the first plane and the second plane; the controller is specifically used to control the leveling structure to adjust the position of the first stage or the second stage according to the distances detected by the multiple distance sensors when the distances detected by the distance sensors are not all the same, so that the distances detected by the distance sensors are the same; or,

[0024] The distance sensor is arranged at the edge of the first carrying surface or the edge of the second carrying surface, and is used to detect the distance between the first carrying surface and the second carrying surface; the controller is specifically used to control the leveling structure to adjust the position of the first carrier plate or the second carrier plate according to the distances detected by the multiple distance sensors when the distances detected by the distance sensors are not all the same, so that the distances detected by the distance sensors are the same.

[0025] In one embodiment, the leveling structure includes a plurality of hydraulic structures arranged at intervals along the circumferential direction, wherein each of the hydraulic structures in the leveling structure is located on a side of the first platform away from the first carrier plate, or each of the hydraulic structures is located on a side of the second platform away from the second carrier plate, or some of the hydraulic structures are located on a side of the first platform away from the first carrier plate, and the remaining hydraulic structures are located on a side of the second platform away from the second carrier plate; each of the hydraulic structures includes a hydraulic cylinder and a hydraulic rod.

[0026] In one embodiment, the leveling structure is multiplexed as the first driving unit.

[0027] In one embodiment, a guide rail is disposed on an inner wall of the bonding chamber, and the carrier driven by the first driving unit can move along the guide rail.

[0028] In one embodiment, the first bearing surface is provided with a pressure sensor, or the second bearing surface is provided with a pressure sensor.

[0029] The wafer bonding device provided in the embodiment of the present application can perform wafer sputtering process and wafer alignment process in the bonding chamber, thereby avoiding contamination or oxidation of the bonding material on the wafer surface and displacement of the wafer position, which is beneficial to improving the bonding quality and bonding accuracy of the wafer. There is no need to transfer the wafer between different chambers, which reduces waiting and processing time, simplifies the process flow and improves production efficiency.

[0030] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0032] Figure 1 A schematic structural diagram of a wafer bonding device provided in one embodiment of the present application;

[0033] Figure 2 for Figure 1 A front view of a first plane of a first stage of the wafer bonding apparatus shown;

[0034] Figure 3 for Figure 1 A front view of a second plane of a second stage of the wafer bonding apparatus shown;

[0035] Figure 4 A schematic diagram of the relative position relationship between a wafer fixed on a second carrier and the second carrier provided in an embodiment of the present application;

[0036] Figure 5 A schematic diagram of the relative position relationship between a wafer fixed to a first carrier and the first carrier provided in one embodiment of the present application. DETAILED DESCRIPTION

[0037] Here, the technical solutions in the embodiments (or "implementations") of the present application will be described clearly and completely in conjunction with the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements.

[0038] If there are terms involving directional indications or positional relationships in the embodiments of the present application (such as up, down, left, right, front, back, inside, outside, top, bottom, center, vertical, horizontal, longitudinal, transverse, length, width, counterclockwise, clockwise, axial, radial, circumferential, etc.), such terms are only used to explain the relative positional relationship, movement, etc. between the components under a certain specific posture (as shown in the accompanying drawings); if the specific posture changes, the directional indication or positional relationship will also change accordingly. In addition, the terms "first", "second", etc. involved in the embodiments of the present application are only used for the purpose of convenience of description and cannot be understood as indicating or implying relative importance.

[0039] The wafer bonding device of the embodiment of the present application is described in detail below in conjunction with the accompanying drawings. In the absence of conflict, the features of the following embodiments and implementations can complement or combine with each other.

[0040] The present application embodiment provides a wafer bonding device, such as Figure 1 As shown, the wafer bonding apparatus includes a bonding chamber 100 , and a first carrier 11 , a second carrier 12 , a driving assembly 20 , a sputtering assembly 30 and a wafer alignment assembly 40 located in the bonding chamber 100 .

[0041] The first carrier 11 includes a first carrying surface 111 for fixing the wafer, and the second carrier 12 includes a second carrying surface 121 for fixing the wafer, and the first carrying surface 111 and the second carrying surface 121 are arranged opposite to each other. The driving assembly 20 includes a first driving part 21, and the first driving part 21 is used to drive the first carrier 11 to move or drive the second carrier 12 to move, or drive the first carrier 11 and the second carrier 12 to move at the same time, so that the wafer fixed on the first carrying surface 111 is bonded with the wafer fixed on the second carrying surface 121. The sputtering assembly 30 is used to deposit bonding material on the surface of the wafer fixed on the first carrying surface 111 and the surface of the wafer fixed on the second carrying surface 121. The wafer alignment assembly 40 is used to align the wafer fixed on the first carrying surface 111 with the wafer fixed on the second carrying surface 121.

[0042] The wafer bonding device provided in the embodiment of the present application fixes the wafers on the first carrying surface 111 and the second carrying surface 121 respectively, deposits bonding materials on the surfaces of the wafers by using the sputtering assembly 30, and aligns the wafers by using the wafer alignment assembly 40. Thereafter, driven by the first driving unit 21, the first carrier 11 and the second carrier 12 are brought closer to each other, so that the wafer located on the first carrying surface 111 and the wafer located on the second carrying surface 121 are attached to each other, and finally the bonding is completed. By sputtering and depositing bonding material on the surface of the wafer, two wafers can be bonded through the bonding material, which can improve the adhesion of the wafer bonding interface and ensure the overall performance and reliability of the wafer after bonding. Compared with the solution of bonding using a hot pressing process, it can avoid damage to the wafer caused by high temperature, which helps to improve the bonding quality. The wafer bonding device of the present application can perform a wafer sputtering process and a wafer alignment process in the bonding chamber 100, avoiding contamination or oxidation of the bonding material on the wafer surface and displacement of the wafer position, which is beneficial to improving the bonding quality and bonding accuracy of the wafer. There is no need to transfer the wafer between different chambers, which can simplify the process flow and improve production efficiency.

[0043] In one embodiment, Figure 1 As shown, the wafer bonding apparatus further includes a first carrier 13 and a second carrier 14, the first carrier 13 includes a first plane 131, the second carrier 14 includes a second plane 141 opposite to the first plane 131, the first carrier 11 is fixed on the first plane 131, and the second carrier 12 is fixed on the second plane 141. In some embodiments, the wafer can be fixed to the first carrying surface 111 of the first carrier 11 and the second carrying surface 121 of the second carrier 12 by vacuum adsorption.

[0044] In one embodiment, Figure 1 As shown, the wafer bonding device further includes an air pump 50, which is connected to the bonding chamber 100. Before depositing the bonding material on the wafer surface, the air pump 50 can be used to extract the air in the bonding chamber 100 and fill the bonding chamber 100 with an inert gas, so that a clean and stable bonding environment is formed in the bonding chamber 100, thereby preventing the bonding material deposited on the wafer surface from being contaminated or oxidized by air, and improving the purity of the bonding interface. In some embodiments, the air pump 50 can be a molecular pump or a dry pump, etc.

[0045] In one embodiment, the wafer bonding apparatus further includes a controller that can control the driving component 20 and the sputtering component 30 .

[0046] In one embodiment, the bonding material is a metal.

[0047] In one embodiment, Figure 1As shown, the sputtering assembly 30 includes a power supply 31 and an electrode 32 connected to the power supply 31, wherein one electrode is an anode and the other is a cathode, and a target material 33 for forming a bonding material can be arranged at the cathode. The power supply 31 can generate plasma, and after the plasma bombards the surface of the target material 33, the atoms or molecules of the target material 33 are bombarded, and these atoms or molecules are deposited on the surface of the wafer to form a bonding layer.

[0048] In one embodiment, the first bearing surface 111 and the second bearing surface 121 are arranged in the vertical direction, and the sputtering assembly 30 is located above the first carrier 11 and the second carrier 12. During the sputtering process, the sputtering assembly 30 can perform sputtering deposition on the surface of the wafer fixed on the first bearing surface 111 and the surface of the wafer fixed on the second bearing surface 121 from above at the same time, thereby improving production efficiency. In addition, in the bonding chamber, the wear between different parts may generate particles, and sputtering particles may also be generated during the sputtering process. When the wafer is fixed vertically, these particles are more likely to slide off the surface of the wafer under the action of gravity, thereby avoiding these particles from affecting the bonding quality of the wafer, which is beneficial to improving the yield of the product.

[0049] In one embodiment, Figure 1 As shown, the driving component 20 also includes a second driving part 22, which is connected to the first carrier 11, and drives the first carrier 11 to rotate around a direction perpendicular to the first carrying surface 111. With this arrangement, while the sputtering component 30 deposits bonding material on the wafer, the second driving part 22 can drive the wafer fixed to the first carrying surface 111 to rotate, so that the bonding material can be evenly deposited on the surface of the wafer fixed to the first carrying surface 111, which is beneficial to improving the bonding quality.

[0050] Specifically, the second driving unit 22 may include a rotating motor and a rotating shaft, which are installed on the first carrier 13, and the rotating shaft can rotate relative to the first carrier 13. One end of the rotating shaft is connected to the rotating motor, and the other end is connected to the first carrier plate 11. The rotating motor drives the rotating shaft to rotate, thereby driving the first carrier plate 11 to rotate.

[0051] In one embodiment, Figure 1 As shown, the driving assembly 20 further includes a third driving unit 23, which is connected to the second carrier plate 12 and drives the second carrier plate 12 to rotate in a direction perpendicular to the second bearing surface 121. In this way, while the sputtering assembly 30 deposits bonding material on the wafer, the third driving unit 23 can drive the wafer fixed on the second bearing surface 121 to rotate, so that the bonding material can be evenly deposited on the surface of the wafer fixed on the second bearing surface 121, which is conducive to improving the bonding quality.

[0052] Specifically, the third driving unit 23 may include a rotating motor and a rotating shaft, which are installed on the second carrier 14, and the rotating shaft can rotate relative to the second carrier 14. One end of the rotating shaft is connected to the rotating motor, and the other end is connected to the second carrier 12. The rotating motor drives the rotating shaft to rotate, thereby driving the second carrier 12 to rotate.

[0053] In one embodiment, during the wafer alignment process, the rotation angle of the first carrier 11 can be controlled by the first driving unit 21 or the rotation angle of the second carrier 12 can be controlled by the third driving unit 23, thereby adjusting the angle of the wafer to ensure the alignment of the two wafer angles. The specific alignment process will be described in detail later.

[0054] In one embodiment, Figures 1 to 3 As shown, the wafer alignment assembly 40 includes an image sensor 41 and a fourth drive unit 42, the image sensor 41 is used to determine the first relative position information between the wafer fixed on the first carrying surface 111 and the first carrying surface 111, and the second relative position information between the wafer fixed on the second carrying surface 121 and the second carrying surface 121, the fourth drive unit 42 is connected to the first carrier 11 or the second carrier 12, and the controller is used to control the fourth drive unit 42 to drive the carrier connected thereto to move according to the first relative position information and the second relative position information.

[0055] The first relative position information and the second relative position information acquired by the image sensor 41 may include the relative distance and relative angle between the wafer and the carrier. The controller is responsible for processing the information data collected by the image sensor 41 and sending instructions to the fourth drive unit 42 according to the processing results. The fourth drive unit 42 adjusts the position of the carrier according to the instructions, thereby driving the wafer to move to the alignment state. The wafer alignment process is completed in the bonding chamber, which is conducive to improving bonding accuracy and production efficiency.

[0056] In one embodiment, Figure 2 and Figure 3 As shown, the image sensor 41 of the wafer alignment assembly 40 includes a first image sensor group 411 disposed on the side of the first carrier 11 and a second image sensor group 412 disposed on the side of the second carrier 12. The first image sensor group 411 and the second image sensor group 412 each include at least two image sensors. Figure 4 and Figure 5As shown, the second image sensor group 412 is used to detect the first relative position information, which at least includes the first distance A1 (A1'), the second distance A2 (A2') and the first angle B1. The first image sensor group 411 is used to detect the second relative position information, which at least includes the third distance A3 (A3'), the fourth distance A4 (A4') and the second angle B2.

[0057] like Figure 5 As shown, the first distance A1 (A1') is the distance between the first intersection M1 (M1') and the second intersection M2 (M2') in the first direction X, and the second distance A2 (A2') is the distance between the third intersection N1 (N1') and the fourth intersection N2 (N2') in the second direction Y.

[0058] The first intersection point M1 (M1') is the intersection point of a straight line passing through the center of the first carrying surface 111 and extending along the first direction X and the edge of the first carrying surface 111; the second intersection point M2 (M2') is the intersection point of a straight line passing through the center of the wafer 200 fixed to the first carrying surface 111 and extending along the first direction X and the edge of the wafer 200. After the second image sensor group 412 acquires an image including the first carrying surface 111 and the wafer 200 carried by the first carrying surface 111, the edge of the wafer 200 carried by the first carrying surface 111 can be detected, and the center of the wafer 200 can be determined.

[0059] The third intersection N1 (N1') is the intersection of a straight line passing through the center of the first carrying surface 111 and extending along the second direction Y and the edge of the first carrying surface 111; the fourth intersection N2 (N2') is the intersection of a straight line passing through the center of the wafer 200 fixed on the first carrying surface 111 and extending along the second direction Y and the edge of the wafer 200.

[0060] The first intersection M1 (M1′) and the second intersection M2 (M2′) are located on the same side of the center of the first bearing surface 111 , and the third intersection N1 (N1′) and the fourth intersection N2 (N2′) are located on the same side of the center of the first bearing surface 111 .

[0061] The first angle B1 is the angle between a first connecting line and a straight line extending along the second direction Y and passing through the center of the wafer 200 fixed on the first supporting surface 111, and the first connecting line is a line connecting the cutout 201 of the wafer 200 fixed on the first supporting surface 111 and the center of the wafer 200; the first direction X is perpendicular to the second direction Y.

[0062] like Figure 4As shown, the third distance A3 (A3') is the distance between the fifth intersection M3 (M3') and the sixth intersection M4 (M4') in the first direction X, and the fourth distance A4 (A4') is the distance between the seventh intersection N3 (N3') and the eighth intersection N4 (N4') in the second direction Y.

[0063] The fifth intersection point M3 (M3') is the intersection point of a straight line passing through the center of the second carrying surface 121 and extending along the first direction X and the edge of the second carrying surface 121; the sixth intersection point M4 (M4') is the intersection point of a straight line passing through the center of the wafer 200 fixed to the second carrying surface 121 and extending along the first direction X and the edge of the wafer 200. After the first image sensor group 411 acquires an image including the second carrying surface 121 and the wafer 200 carried by the second carrying surface 121, the edge of the wafer 200 carried by the second carrying surface 121 can be detected, and the center of the wafer 200 can be determined.

[0064] The seventh intersection N3 (N3') is the intersection of a straight line passing through the center of the second carrying surface 121 and extending along the second direction Y and the edge of the second carrying surface 121; the eighth intersection N4 (N4') is the intersection of a straight line passing through the center of the wafer 200 fixed on the second carrying surface 121 and extending along the second direction Y and the edge of the wafer 200.

[0065] The fifth intersection M3 (M3′) and the sixth intersection M4 (M4′) are located on the same side of the center of the second bearing surface 121 , and the seventh intersection N3 (N3′) and the eighth intersection N4 (N4′) are located on the same side of the center of the second bearing surface 121 .

[0066] The second angle B2 is the angle between the second connecting line and the straight line extending along the second direction Y and passing through the center of the wafer 200 fixed on the second supporting surface 121; the second connecting line is the connecting line between the cutout 201 of the wafer 200 fixed on the second supporting surface 121 and the center of the wafer 200.

[0067] like Figure 4 and Figure 5 As shown, the controller first controls the fourth driving unit and the carrier connected thereto to rotate according to the difference between the first angle B1 and the second angle B2, and then controls the fourth driving unit 42 to drive the carrier connected thereto to move a distance in the first direction X that is the difference between the first distance A1 (A1') and the third distance A3 (A3'), and a distance in the second direction Y that is the difference between the second distance A2 (A2') and the fourth distance A4 (A4').

[0068] In one embodiment, the first image sensor group 411 detects the third distance A3' and the third distance A3, and the second image sensor group 412 detects the first distance A1' and the first distance A1. In this embodiment, the controller can calculate the first difference between the third distance A3' and the first distance A1' and the second difference between the third distance A3 and the first distance A1, and control the fourth driving unit to drive the carrier connected thereto to move in the first direction to a distance equal to the average value of the first difference and the second difference.

[0069] In one embodiment, the first image sensor group 411 detects the fourth distance A4' and the fourth distance A4, and the second image sensor group 412 detects the second distance A2' and the second distance A2. In this embodiment, the controller can calculate the third difference between the fourth distance A4' and the second distance A2' and the fourth difference between the fourth distance A4' and the second distance A2, and control the fourth driving unit to drive the carrier connected thereto to move in the second direction to an average value of the third difference and the fourth difference.

[0070] In this embodiment, the size of the first carrying surface 111 of the first carrier 11 is the same as the size of the second carrying surface 121 of the second carrier 12, and the centers of the two are opposite. Before the wafer is placed on the first carrying surface 111 and the second carrying surface 121, a pre-alignment is performed, so that the center of the wafer carried by the first carrying surface 111 coincides with the center of the first carrying surface 111, or the distance between the two is very small (generally less than 300μm), and the center of the wafer carried by the second carrying surface 121 coincides with the center of the second carrying surface 121, or the distance between the two is very small (generally less than 300μm). During the alignment process, one of the carriers remains stationary, and the fourth driving unit drives the other carrier to rotate by an angle equal to the difference between the first angle B1 and the second angle B2, so that the cuts of the two wafers are basically aligned, meeting the precision requirements of the process; thereafter, the fourth driving unit drives the carrier to move relative to the other carrier in the first direction X by a distance equal to the difference between the first distance A1 (A1') and the third distance A3 (A3'), and the two wafers 200 are aligned in the first direction X, and then move in the second direction Y by a distance equal to the difference between the second distance A2 (A2') and the fourth distance A4 (A4'), and the two wafers 200 are aligned in the second direction Y, at which time the edges and centers of the two wafers are aligned.

[0071] It should be noted that when the cuts of the two wafers are located on the same side of a straight line extending along the second direction Y and passing through the center of the wafer, the first angle B1 and the second angle B2 are both positive values; when the cuts of the two wafers are located on different sides of a straight line extending along the second direction Y and passing through the center of the wafer, the first angle B1 is positive and the second angle B2 is negative, or the first angle B1 is negative and the second angle B2 is positive.

[0072] Through the above-mentioned setting, after sputtering the bonding material on the wafer surface, the wafer alignment assembly can be used to accurately determine the position information of the wafer, and precise alignment between wafers can be achieved by adjusting the position and angle of the carrier, which is beneficial to improving the bonding accuracy and ensuring the reliability of wafer bonding. There is no need to transfer the wafer to external equipment for alignment, and the operation is simple and quick.

[0073] In one embodiment, Figure 4 and Figure 5 As shown, the first direction X is perpendicular to the second direction Y. Specifically, the first direction X is a horizontal direction, and the second direction Y is a vertical direction. Figure 4 A front view of the wafer and the second carrying surface 121 obtained when observing the second carrying surface 121 from the direction of the first carrying plate 11 pointing to the second carrying plate 12; Figure 5 is a front view of the wafer and the first carrying surface 111 obtained when observing the first carrying surface 111 from the direction from the second carrying plate 12 to the first carrying plate 11, Figure 4 In the embodiment shown, the first distance A1 is located on the left side of the wafer 200. Figure 5 In the illustrated embodiment, the third distance A3 is located on the right side of the wafer 200 .

[0074] In one embodiment, Figure 2 and Figure 4 As shown, the fourth distance and the second angle are detected by the same image sensor of the first image sensor group 411. Such an arrangement can reduce the number of required image sensors, which is beneficial to reducing the cost and complexity of the wafer alignment assembly.

[0075] In some embodiments, the first image sensor group 411 includes two image sensors: a first image sensor and a second image sensor, the first image sensor is used to detect the third distance A3, and the second image sensor is used to detect the fourth distance A4 and the second angle B2. Alternatively, the first image sensor group 411 includes three image sensors: a first image sensor, a second image sensor, and a third image sensor, the first image sensor is used to detect the third distance A3, the second image sensor is used to detect the fourth distance A4 and the second angle B2, and the third image sensor is used to detect the third distance A3'. Alternatively, Figure 2 As shown, the first image sensor group 411 includes four image sensors: a first image sensor 4111, a second image sensor 4112, a third image sensor 4113 and a fourth image sensor 4114. The first image sensor 4111 is used to detect the third distance A3, the second image sensor 4112 is used to detect the fourth distance A4 and the second angle B2, the third image sensor 4113 is used to detect the third distance A3', and the fourth image sensor 4114 is used to detect the fourth distance A4'.

[0076] In one embodiment, the third distance, the fourth distance and the second angle are respectively detected by different image sensors of the first image sensor group 411 .

[0077] In one embodiment, Figure 3 and Figure 5 As shown, the second distance and the first angle B1 are detected by the same image sensor of the second image sensor group 412 .

[0078] In some embodiments, the second image sensor group 412 includes two image sensors: a first image sensor and a second image sensor, the first image sensor is used to detect the first distance A1, and the second image sensor is used to detect the second distance A2 and the first angle B1. Alternatively, the second image sensor group 412 includes three image sensors: a first image sensor, a second image sensor, and a third image sensor, the first image sensor is used to detect the first distance A1, the second image sensor is used to detect the second distance A2 and the first angle B1, and the third image sensor is used to detect the first distance A1'. Alternatively, Figure 3 As shown, the second image sensor group 412 includes four image sensors: a first image sensor 4121, a second image sensor 4122, a third image sensor 4123 and a fourth image sensor 4124. The first image sensor 4121 is used to detect the first distance A1, the second image sensor 4122 is used to detect the second distance A2 and the first angle B1, the third image sensor 4123 is used to detect the first distance A1', and the fourth image sensor 4124 is used to detect the second distance A2'.

[0079] In one embodiment, the first distance, the second distance, and the first angle B1 are respectively detected by different image sensors of the second image sensor group 412 .

[0080] In one embodiment, Figure 1 and Figure 3 As shown, the fourth driving part 42 includes a first screw 421, a first motor, a second screw 422, a second motor and a rotating part 423. The first screw 421 extends along the first direction X, and the second screw 422 extends along the second direction Y. The controller controls the motor to drive the carrier connected to the fourth driving part 42 to move along the first screw 421 and the second screw 422, and also controls the rotating part 423 to drive the carrier connected to it to rotate around a direction perpendicular to its bearing surface. Through the above configuration, as Figure 3 , Figure 4 and Figure 5As shown, the extension direction of the first lead screw 421 is the same as the first direction X, and the extension direction of the second lead screw 422 is the same as the second direction Y. After the image sensor 41 obtains the position information of the wafer, the rotating part 423 drives the carrier to rotate, and the first motor drives the carrier connected to the fourth driving part 42 to move along the first lead screw 421. The second motor drives the carrier connected to the fourth driving part 42 to move along the second lead screw 422, which can drive the two wafers to be aligned. This can simplify the movement process of the carrier during wafer alignment and is also beneficial to improving the accuracy of wafer bonding.

[0081] In one embodiment, Figure 1 As shown, the second driving unit 22 is connected to the first carrier 11, driving the first carrier 11 to rotate around a direction perpendicular to the first carrying surface 111, and when the fourth driving unit 42 is drivingly connected to the first carrier 11, the second driving unit 22 is reused as the fourth driving unit 42. In this way, it is helpful to simplify the structural complexity of the wafer bonding device and reduce the manufacturing cost.

[0082] In one embodiment, the third driving unit 23 is connected to the second carrier 12, driving the second carrier 12 to rotate in a direction perpendicular to the second bearing surface 121. When the fourth driving unit 42 is drivingly connected to the second carrier 12, the third driving unit 23 is reused as the fourth driving unit 42. This helps to simplify the structural complexity of the wafer bonding device and reduce the manufacturing cost.

[0083] In one embodiment, Figure 1 and Figure 3 As shown, the wafer alignment assembly further includes a plurality of distance sensors 60 and a leveling structure 24, and the controller is used to control the leveling structure 24 according to the distances detected by the plurality of distance sensors 60, so that the distances detected by the distance sensors 60 are the same. The distance sensors 60 and the leveling structure 24 can ensure the parallelism of the wafers during wafer bonding, improve the bonding strength and bonding uniformity, and reduce voids, cracks or other defects in the bonding layer.

[0084] In one embodiment, the first stage 13 includes a first plane 131, the second stage 14 includes a second plane 141 opposite to the first plane 131, the first carrier 11 is fixed on the first plane 131, and the second carrier 12 is fixed on the second plane 141. The distance sensor 60 is disposed on the first plane 131 or the second plane 141, and is used to detect the distance between the first plane 131 and the second plane 141. The controller is specifically used to control the leveling structure 24 to adjust the position of the first stage 13 or the second stage 14 according to the distances detected by the multiple distance sensors 60 when the distances detected by the distance sensors 60 are not all the same, so that the distances detected by the distance sensors 60 are the same.

[0085] During the wafer bonding process, the first stage 13 and the second stage 14 approach each other, and finally the wafer on the first carrier 11 and the wafer on the second carrier 12 are attached and bonded. In this process, the distance sensor 60 can determine whether the first plane 131 and the second plane 141 are parallel by detecting the distance between the first plane 131 and the second plane 141. When the two are not parallel, the first stage 13 or the second stage 14 can be adjusted in real time through the leveling structure 24. With this arrangement, the parallelism adjustment of the first plane 131 and the second plane 141 is simple, and the distance sensor 60 is arranged on the stage, which can prevent the sputtering particles generated during the sputtering process from falling on the distance sensor 60, thereby ensuring the normal operation of the distance sensor 60.

[0086] In one embodiment, the number of distance sensors 60 is at least three. Figure 3 As shown, the second carrier 14 is provided with four distance sensors 60 evenly distributed along the circumference of the second carrier 12 .

[0087] In one embodiment, the distance sensor is disposed at the edge of the first carrying surface 111 or the edge of the second carrying surface 121, and is used to detect the distance between the first carrying surface 111 and the second carrying surface 121. The controller is specifically used to control the leveling structure 24 to adjust the position of the first carrier 11 or the second carrier 12 according to the distances detected by the multiple distance sensors when the distances detected by the distance sensors are not all the same, so that the distances detected by the distance sensors are the same. Since the first carrying surface 111 and the second carrying surface 121 are planes for directly fixing the wafer, the distance between the first carrying surface 111 and the second carrying surface 121 is directly detected by the distance sensor, and the accuracy is higher.

[0088] In one embodiment, the number of distance sensors 60 is at least three. Figure 3As shown, the second carrier 14 is provided with four distance sensors 60 evenly distributed along the circumference of the second carrier 12. Figure 1 As shown, the leveling structure 24 includes a plurality of hydraulic structures 211 arranged at intervals along the circumferential direction, each of the hydraulic structures 211 in the leveling structure 24 is located on the side of the first stage 13 away from the first carrier 11, or each of the hydraulic structures is located on the side of the second stage 14 away from the second carrier 12, or some of the hydraulic structures 211 are located on the side of the first stage 13 away from the first carrier 11, and the remaining hydraulic structures are located on the side of the second stage 14 away from the second carrier 12, and each of the hydraulic structures 211 includes a hydraulic cylinder and a hydraulic rod. When the distance sensor 60 detects that the distances between the first plane 131 and the second plane 141 are not completely the same, the position of the stage can be precisely adjusted by adjusting the telescopic length of the hydraulic rod to ensure the parallelism between the two wafers.

[0089] In one embodiment, Figure 1 As shown, the leveling structure 24 is reused as the first driving unit 21. Such a configuration can simplify the structure of the wafer bonding device and reduce the manufacturing cost. During the wafer bonding process, the leveling structure 24 can drive the first stage 13 or the second stage 14 to approach the direction where the other stage is located, so that the wafer fixed on the first stage 13 and the wafer fixed on the second stage 14 are attached and pressure is applied to the wafers, and finally the wafer bonding is completed.

[0090] In one embodiment, Figure 1 As shown, the inner wall of the bonding chamber 100 is provided with a guide rail 101, and the carrier driven by the first driving unit 21 can move along the guide rail 101. In this way, the carrier moves along a predetermined path, ensuring stability and accuracy during the movement of the carrier.

[0091] In one embodiment, Figure 1 As shown, the first bearing surface 111 is provided with a pressure sensor 70, or the second bearing surface is provided with a pressure sensor 70. The pressure detection sensor 70 can detect the pressure value borne by the wafer fixed on the bearing surface, and the controller can control the pressure during wafer bonding according to the pressure value to ensure that the wafer is evenly stressed during the bonding process, thereby improving the wafer bonding quality.

[0092] The process of bonding wafers using the wafer bonding device provided in the embodiment of the present application is as follows:

[0093] First, the controller controls the sputtering assembly 30 , the second driving unit 22 and the third driving unit 23 to work simultaneously, and deposit bonding materials on the two wafers respectively.

[0094] Subsequently, after the deposition of the bonding material is completed, the controller controls the sputtering assembly 30 , the second driving unit 22 and the third driving unit 23 to stop working.

[0095] Then, the controller controls the leveling structure 24 to perform leveling according to the data detected by the distance sensor 60 .

[0096] Then, the controller controls the fourth driving unit 42 to drive the carrier connected thereto to move and rotate according to the data detected by the image sensor 41 , so as to align the two wafers.

[0097] Then, the controller controls the first driving unit 21 to drive the carrier connected thereto to move so that the two wafers are bonded.

[0098] It should be noted that the technical solutions or technical features described in the above embodiments can be combined or supplemented with each other without causing conflicts. The scope of protection of this application is not limited to the precise structures described in the above embodiments and shown in the drawings; all modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of this application should be included in the scope of protection of this application.

Claims

1. A wafer bonding device, characterized in that: The wafer bonding device comprises a bonding chamber, and a first carrier, a second carrier, a driving component, a sputtering component and a wafer alignment component located in the bonding chamber; The first carrier includes a first carrying surface for fixing the wafer; the second carrier includes a second carrying surface for fixing the wafer, and the first carrying surface is arranged opposite to the second carrying surface; the driving assembly includes a first driving part, and the first driving part is used to drive the first carrier and / or the second carrier to move, so that the wafer fixed on the first carrying surface is bonded with the wafer fixed on the second carrying surface; The sputtering assembly is used to deposit bonding material onto the surface of the wafer fixed to the first carrying surface and the surface of the wafer fixed to the second carrying surface; The wafer alignment assembly is used to align the wafer fixed on the first carrying surface with the wafer fixed on the second carrying surface.

2. The wafer bonding device according to claim 1, characterized in that: The first carrying surface and the second carrying surface are arranged along a vertical direction, and the sputtering assembly is located above the first carrying plate and the second carrying plate.

3. The wafer bonding device according to claim 2, characterized in that: The driving assembly further includes a second driving part; the second driving part is connected to the first carrier plate, driving the first carrier plate to rotate in a direction perpendicular to the first bearing surface; and / or The driving assembly further includes a third driving unit; the third driving unit is connected to the second carrier plate and drives the second carrier plate to rotate in a direction perpendicular to the second carrying surface.

4. The wafer bonding device according to claim 1, characterized in that: The wafer bonding device further includes a controller, the wafer alignment assembly includes an image sensor and a fourth driving unit, the image sensor is used to determine first relative position information between the wafer fixed on the first carrying surface and the first carrying surface, and second relative position information between the wafer fixed on the second carrying surface and the second carrying surface; The fourth driving unit is connected to the first carrier plate and / or the second carrier plate, and the controller is used to control the fourth driving unit to drive the carrier plate connected thereto to move according to the first relative position information and the second relative position information.

5. The wafer bonding device according to claim 4, characterized in that: The image sensor of the wafer alignment assembly includes a first image sensor group arranged on the side of the first carrier and a second image sensor group arranged on the side of the second carrier; the first image sensor group and the second image sensor group respectively include at least two image sensors; the second image sensor group is used to detect first relative position information, the first relative position information at least includes a first distance, a second distance and a first angle; the first image sensor group is used to detect second relative position information, the second relative position information at least includes a third distance, a fourth distance and a second angle; The first distance is the distance between the first intersection and the second intersection in the first direction, and the second distance is the distance between the third intersection and the fourth intersection in the second direction; the first intersection is the intersection of a straight line passing through the center of the first bearing surface and extending along the first direction and an edge of the first bearing surface; The second intersection point is an intersection point of a straight line passing through the center of the wafer fixed on the first carrying surface and extending along the first direction and an edge of the wafer; The third intersection point is an intersection point of a straight line passing through the center of the first bearing surface and extending along the second direction and an edge of the first bearing surface; The fourth intersection is the intersection of a straight line passing through the center of the wafer fixed on the first supporting surface and extending along the second direction and the edge of the wafer; the first intersection and the second intersection are located on the same side of the center of the first supporting surface, and the third intersection and the fourth intersection are located on the same side of the center of the first supporting surface; the first angle is the angle between a first connecting line and a straight line extending along the second direction and passing through the center of the wafer fixed on the first supporting surface, and the first connecting line is a line connecting the cutout of the wafer fixed on the first supporting surface and the center of the wafer; the first direction is perpendicular to the second direction; The third distance is the distance between the fifth intersection and the sixth intersection in the first direction, and the fourth distance is the distance between the seventh intersection and the eighth intersection in the second direction; the fifth intersection is the intersection of a straight line passing through the center of the second bearing surface and extending along the first direction and an edge of the second bearing surface; The sixth intersection point is an intersection point of a straight line passing through the center of the wafer fixed on the second carrying surface and extending along the first direction and an edge of the wafer; The seventh intersection point is an intersection point of a straight line passing through the center of the second bearing surface and extending along the second direction and an edge of the second bearing surface; The eighth intersection is the intersection of a straight line passing through the center of the wafer fixed on the second carrying surface and extending along the second direction and the edge of the wafer; the fifth intersection and the sixth intersection are located on the same side of the center of the second carrying surface, and the seventh intersection and the eighth intersection are located on the same side of the center of the second carrying surface; the second angle is the angle between the second connecting line and a straight line extending along the second direction and passing through the center of the wafer fixed on the second carrying surface; the second connecting line is a line connecting the cutout of the wafer fixed on the second carrying surface and the center of the wafer; The controller first controls the fourth driving unit to drive the carrier connected to it to rotate according to the difference between the first angle and the second angle, and then controls the fourth driving unit to drive the carrier connected to it to move a distance in the first direction that is the difference between the first distance and the third distance, and a distance in the second direction that is the difference between the second distance and the fourth distance.

6. The wafer bonding device according to claim 5, characterized in that: The fourth distance and the second angle are detected by the same image sensor of the first image sensor group; or, the third distance, the fourth distance and the second angle are respectively detected by different image sensors of the first image sensor group.

7. The wafer bonding device according to claim 5, characterized in that: The second distance and the first angle are detected by the same image sensor of the second image sensor group; or, the first distance, the second distance and the first angle are respectively detected by different image sensors of the second image sensor group.

8. The wafer bonding device according to claim 5, characterized in that: The fourth driving part includes a first lead screw, a first motor, a second lead screw, a second motor and a rotating part; the first lead screw extends along the first direction, and the second lead screw extends along the second direction; the controller controls the motor to drive the carrier connected to the fourth driving part to move along the first lead screw or the second lead screw, and also controls the rotating part to drive the carrier connected to it to rotate in a direction perpendicular to its bearing surface.

9. The wafer bonding device according to claim 8, characterized in that: The driving assembly further includes a second driving unit; the second driving unit is connected to the first carrier plate, driving the first carrier plate to rotate in a direction perpendicular to the first bearing surface; when the fourth driving unit is drivingly connected to the first carrier plate, the second driving unit is reused as the fourth driving unit; and / or, The driving assembly also includes a third driving unit; the third driving unit is connected to the second carrier plate to drive the second carrier plate to rotate in a direction perpendicular to the second bearing surface; when the fourth driving unit is drivingly connected to the second carrier plate, the third driving unit is reused as the fourth driving unit.

10. The wafer bonding device according to claim 1, characterized in that: The wafer bonding device also includes a controller; the wafer alignment assembly also includes multiple distance sensors and a leveling structure; the controller is used to control the leveling structure according to the distances detected by the multiple distance sensors so that the distances detected by each distance sensor are the same.

11. The wafer bonding device according to claim 10, characterized in that: The wafer bonding device further comprises a first carrier for arranging the first carrier, and a second carrier for arranging the second carrier; The first stage includes a first plane, the second stage includes a second plane opposite to the first plane, the first carrier is fixed on the first plane, and the second carrier is fixed on the second plane; the distance sensor is arranged on the first plane or the second plane, and is used to detect the distance between the first plane and the second plane; the controller is specifically used to control the leveling structure to adjust the position of the first stage or the second stage according to the distances detected by the multiple distance sensors when the distances detected by the distance sensors are not all the same, so that the distances detected by the distance sensors are the same; or, The distance sensor is arranged at the edge of the first carrying surface or the edge of the second carrying surface, and is used to detect the distance between the first carrying surface and the second carrying surface; the controller is specifically used to control the leveling structure to adjust the position of the first carrier plate or the second carrier plate according to the distances detected by the multiple distance sensors when the distances detected by the distance sensors are not all the same, so that the distances detected by the distance sensors are the same.

12. The wafer bonding device according to claim 10, characterized in that: The leveling structure includes a plurality of hydraulic structures arranged at intervals along the circumferential direction, wherein each of the hydraulic structures in the leveling structure is located on a side of the first platform away from the first carrier plate, or each of the hydraulic structures is located on a side of the second platform away from the second carrier plate, or some of the hydraulic structures are located on a side of the first platform away from the first carrier plate, and the remaining hydraulic structures are located on a side of the second platform away from the second carrier plate; each of the hydraulic structures includes a hydraulic cylinder and a hydraulic rod.

13. The wafer bonding device according to claim 12, characterized in that: The leveling structure is reused as the first driving unit.

14. The wafer bonding device according to claim 1, characterized in that: The inner wall of the bonding chamber is provided with a guide rail, and the carrier driven by the first driving part can move along the guide rail.

15. The wafer bonding device according to claim 1, characterized in that: The first bearing surface is provided with a pressure sensor, or the second bearing surface is provided with a pressure sensor.

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