CN119673815A - Wafer bonding device and wafer bonding method - Google Patents

Abstract

The present invention provides a wafer bonding device and a wafer bonding method, and relates to the field of semiconductor processing technology. The wafer bonding device includes a carrier, a driving structure arranged on the carrier, and a target chuck and a carrier chuck arranged along the Z direction, at least one of the target chuck and the carrier chuck is connected to the driving structure by transmission, and the driving structure is configured to: be able to drive the target chuck and the carrier chuck to move relative to each other along the X-Y direction and the Z direction; the edge of the target chuck is provided with a plurality of notches; the carrier is provided with a plurality of visual systems, the plurality of visual systems are located on the side of the target chuck away from the carrier chuck, the axial directions of the plurality of visual systems are consistent with the Z direction and correspond to the plurality of notches one by one, and are configured to: take images of the wafers loaded on the target chuck and the carrier chuck corresponding to the notches. The wafer bonding quality of the wafer bonding device is better, the yield is higher, the volume is compact, and the space occupied is small.

Description

Wafer bonding device and wafer bonding method

Technical Field

The present invention relates to the field of semiconductor processing technologies, and in particular, to a wafer bonding device and a wafer bonding method.

Background

The wafer bonding technology is to tightly combine two wafers with clean surfaces into a whole under the action of external force, wherein the alignment precision of the wafers is an important characterization parameter of the bonding technology.

In the wafer bonding device of the related art, a C-shaped arm is generally adopted, vision systems are arranged at the upper end and the lower end of the C-shaped arm to shoot upper and lower wafers, three process positions of a wafer transfer position, a middle position and an alignment position are arranged along the horizontal direction, when the wafer bonding device is used, the upper chuck and the lower chuck are driven to move between the three process positions through a driving structure, and the C-shaped arm is driven to transversely move, so that the alignment operation on the upper and lower wafers can be completed in a matched mode, wherein the displacement of the C-shaped arm and the driving structure is large, measurement errors are introduced, the alignment accuracy is poor, the quality of wafer bonding is poor correspondingly, the interaction time of each process is long, the time consumption is high, the bonding efficiency and the yield of the wafer bonding device are low, and meanwhile, the wafer bonding device transversely needs three process positions, and is complex in structure, large in size and large in occupied space.

Disclosure of Invention

The invention aims to provide a wafer bonding device and a wafer bonding method, which are used for solving the technical problems of poor wafer bonding quality, low yield, large volume and large occupied space of the wafer bonding device in the related art.

In order to solve the problems, the invention provides a wafer bonding device, which comprises a carrier seat, a driving structure arranged on the carrier seat, and a target chuck and a carrier chuck which are arranged along a Z direction, wherein the target chuck and/or the carrier chuck is connected with the driving structure in a transmission way, and the driving structure is configured to drive the target chuck and the carrier chuck to move relatively along an X-Y direction and a Z direction;

the wafer carrier comprises a carrier seat, a plurality of vision systems, a plurality of Z-direction detection units and a plurality of Z-direction detection units, wherein the edges of the target chuck are provided with a plurality of gaps, the carrier seat is provided with a plurality of vision systems, the vision systems are positioned on one side of the target chuck, which is away from the carrier chuck, the axial directions of the vision systems are consistent with the Z-direction and correspond to the gaps one by one, and the wafer carrier seat is configured to shoot images of wafers loaded on the target chuck and the carrier chuck, which correspond to the gaps.

Optionally, the target chuck has an X-direction translational degree of freedom and a Y-direction translational degree of freedom under the drive of the drive structure.

Optionally, one of the notches corresponds to a notch position of a wafer loaded on the target chuck, and the driving structure is configured to drive the target chuck and the carrier chuck to rotate around a Z-axis.

Optionally, one of the chucks is used as a lifting chuck, the lifting chuck has Z-direction translational freedom degree under the drive of the driving structure, and the thimble structure corresponding to the lifting chuck is relatively and fixedly connected with the carrier.

Optionally, the driving structure includes a hexapod displacement platform, a fixed end of the hexapod displacement platform is fixedly connected to the carrier, and a moving end of the hexapod displacement platform is connected to one of the chucks.

The invention also provides a wafer bonding method, which adopts the wafer bonding device, and comprises the following steps:

Determining a transfer sequence of the target chuck and the carrying chuck according to the X-direction translational degree of freedom and the Y-direction translational degree of freedom of the target chuck;

Transmitting a first wafer to a chuck with the determined wafer transmitting sequence in front, and shooting a first image of the first wafer positioned at a bonding position;

transmitting a second wafer to a chuck with a determined wafer transmission sequence at the back, adjusting the first wafer to avoid a shooting path in the X-Y direction, and shooting a second image of the second wafer at a bonding position;

acquiring the circle center offset of the first wafer and the second wafer in the X-Y direction according to the first image and the second image;

The target chuck and the bearing chuck which are positioned at the bonding position are aligned according to the circle center offset;

And carrying out bonding treatment on the first wafer and the second wafer.

Optionally, the step of determining the transfer sequence of the target chuck and the carrying chuck according to the X-direction translational degree of freedom and the Y-direction translational degree of freedom of the target chuck includes:

judging whether the target chuck has X-direction translational freedom and/or Y-direction translational freedom;

If yes, determining that the transfer sequence of the target chuck is positioned before the transfer sequence of the bearing chuck, or determining that the transfer sequence of the bearing chuck is positioned before the transfer sequence of the target chuck;

if not, determining that the transfer sequence of the carrying chuck is positioned before the transfer sequence of the target chuck.

Optionally, when the transfer sequence of the target chuck is located before the transfer sequence of the carrying chuck, the step of adjusting the first wafer to avoid the photographing path in the X-Y direction includes driving the target chuck and the carrying chuck to relatively move along the X-Y direction so as to move the first wafer to a position avoiding the photographing path;

When the wafer transfer sequence of the carrying chuck is positioned before the wafer transfer sequence of the target chuck, the step of adjusting the first wafer to avoid the shooting path in the X-Y direction comprises the step of keeping the carrying chuck fixed in the X-Y direction so as to enable the first wafer to avoid the shooting path in the X-Y direction.

Optionally, the step of capturing a first image of the first wafer at the bonding position includes:

Judging whether a chuck for loading the first wafer has a Z-direction translation degree of freedom;

if yes, driving the chuck to move up and down along the Z direction to a bonding position, and shooting a first image of the first wafer;

if not, directly shooting a first image of the first wafer.

Optionally, the wafer bonding method further includes:

Acquiring deflection amounts of the first wafer and the second wafer around a Z axis according to the first image and the second image;

And a step of performing a bonding process on the first wafer and the second wafer after adjusting the target chuck and the carrier chuck positioned at the bonding position according to the deflection amount.

According to the wafer bonding device and the wafer bonding method, a plurality of vision systems are arranged on one side of the target chuck, the vision systems do not need to be displaced in the operation process, the target chuck and the bearing chuck do not need to be displaced in the X-Y direction or only do small-stroke lateral movement under the driving of the driving structure so as to avoid gaps at the edge of the target chuck, the target chuck and the bearing chuck only need to do small-stroke lifting movement under the driving of the driving structure in the Z direction so as to reach bonding positions or avoiding positions, the displacement of the vision systems and the driving assembly is small in the operation process, the introduced error is small, the accuracy of the measured circle center offset is improved, the alignment accuracy and the bonding quality of the first bonding wafer and the second bonding wafer are correspondingly improved, meanwhile, the interaction time of the operation process can be shortened, the time consumption and the yield in the operation process can be reduced, in addition, the displacement of the vision systems, the target chuck and the bearing chuck is small in the X-Y direction, only need to be one process position in the bonding positions, the wafer bonding device is also improved, the structural simplicity, the bonding volume of the wafer bonding device is reduced, and the bonding device occupies space of the wafer bonding device is also improved, and the bonding device is flexible.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are needed in the description of the embodiments or the prior art will be briefly described, and it is obvious that the drawings in the description below are some embodiments of the present invention, and other drawings can be obtained according to the drawings without inventive effort for a person skilled in the art.

FIG. 1 is an isometric view of a wafer bonding apparatus according to an embodiment of the present invention;

Fig. 2 is a longitudinal sectional view of a wafer bonding apparatus according to an embodiment of the present invention;

FIG. 3 is an isometric view of the wafer bonding apparatus of FIG. 1 with the load chuck and upper thimble structure removed;

FIG. 4 is a top view of the wafer bonding apparatus of FIG. 1 with the load chuck and upper thimble structure removed;

FIG. 5 is a schematic diagram illustrating a first process of a wafer bonding method according to an embodiment of the present invention;

FIG. 6 is a schematic diagram illustrating a second process of the wafer bonding method according to an embodiment of the present invention;

fig. 7 is a third flow chart of a wafer bonding method according to an embodiment of the present invention.

Reference numerals illustrate:

100-carrier, 200-driving structure, 300-target chuck, 310-notch, 400-carrier chuck, 40A-through hole, 500-vision system, 510-focusing component, 520-camera component, 600-base, 700-vibration isolation component, 810-upper thimble structure, 820-lifting component and 900-lower thimble structure.

Detailed Description

The following description of the embodiments of the present invention will be made apparent and fully in view of the accompanying drawings, in which some, but not all embodiments of the invention are shown. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

In the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, unless explicitly stated or limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected, mechanically connected, electrically connected, directly connected, indirectly connected via an intervening medium, or in communication between two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.

The embodiment provides a wafer bonding apparatus, as shown in fig. 1-4, comprising a carrier 100, a driving structure 200 disposed on the carrier 100, and a target chuck 300 and a carrier chuck 400 arranged along a Z-direction, wherein at least one of the target chuck 300 and the carrier chuck 400 is in driving connection with the driving structure 200, the driving structure 200 is configured to drive the target chuck 300 and the carrier chuck 400 to move relatively along an X-Y direction and a Z-direction, a plurality of notches 310 are disposed at an edge of the target chuck 300, the carrier 100 is provided with a plurality of vision systems 500, the plurality of vision systems 500 are disposed at a side of the target chuck 300 facing away from the carrier chuck 400, and the plurality of vision systems 500 are axially aligned with the Z-direction and are in one-to-one correspondence with the plurality of notches 310, and are configured to capture images of wafers loaded on the target chuck 300 and the carrier chuck 400 corresponding to the notches 310.

In the wafer bonding apparatus provided in this embodiment, one of the target chuck 300 and the carrier chuck 400 is used as an upper chuck, the other is used as a lower chuck, the two chucks are arranged at intervals along the Z direction, and can relatively move in translation along the X-Y direction and relatively move up and down along the Z direction under the driving of the driving structure 200, specifically, the target chuck 300 and the carrier chuck 400 can be both connected to the driving structure 200, or the target chuck 300 is connected to the driving structure 200, the carrier chuck 400 is fixedly arranged on the carrier 100, or the target chuck 300 is fixedly arranged on the carrier 100, and the carrier chuck 400 is in transmission connection with the driving structure 200.

The chucks adjacent to the vision system 500 are used as the target chucks 300, the number of the vision systems 500 is at least three, and the vision systems 500 are arranged at intervals along the circumferential direction of the target chucks 300, preferably, the vision systems 500 are uniformly arranged at intervals along the circumferential direction of the target chucks 300, when the wafer is loaded on the target chucks 300 or the carrying chucks 400, the shooting area of the vision system 500 comprises an extending area of the corresponding notch 310 along the Z direction, when the wafer is loaded on the target chucks 300 or the carrying chucks 400, the edge area of the wafer corresponding to the notch 310 is positioned in the shooting area of the vision system 500, and then the vision system 500 can shoot images of the wafer at the edge area of the corresponding notch 310 when no shielding exists between the target chucks 300 and the carrying chucks 400 and the vision systems 500.

For the wafer bonding apparatus, the present embodiment also provides a wafer bonding method, and fig. 5 is a schematic flow chart of the wafer bonding method according to the embodiment of the present invention. As shown in fig. 5, the wafer bonding method includes the steps of:

s502, determining the transfer sequence of the target chuck 300 and the carrying chuck 400 according to the X-direction translational freedom and the Y-direction translational freedom of the target chuck 300.

The target chuck 300 is located between the plurality of vision systems 500 and the carrier chuck 400 along the Z direction, and the target chuck 300 and the carrier chuck 400 are approximately coaxially arranged along the Z direction, when the target chuck 300 transfers a wafer before the carrier chuck 400, the wafer loaded on the target chuck 300 can block the notch 310 to affect the vision system 500 to photograph the edge area of the wafer loaded on the carrier chuck 400 through the notch 310, therefore, according to whether the target chuck 300 has one of the X-direction translational degree of freedom and the Y-direction translational degree of freedom, whether the target chuck 300 can translate after the wafer is loaded in front can avoid the blocking of the vision system 500, and the wafer transfer sequence of the target chuck 300 and the carrier chuck 400 is correspondingly set to ensure the vision system 500 to photograph the edge area of the wafer loaded on the target chuck 300 and the carrier chuck 400. Specifically, in this condition, the target chuck 300 may have only X-direction translational degrees of freedom, only Y-direction translational degrees of freedom, both X-direction translational degrees of freedom and Y-direction translational degrees of freedom, or no X-direction translational degrees of freedom and Y-direction translational degrees of freedom.

S504, the first wafer is transferred to the chuck with the front transfer sequence determined, and a first image of the first wafer at the bonding position is shot.

The wafer transferred is used as the first wafer, after the chuck in front of the transfer sequence receives the first wafer, the wafer can be kept in place or can move along the Z direction under the driving of the driving structure 200 to reach the bonding position, at this time, the notch 310 is not blocked, and the plurality of vision systems 500 take the images of the first wafer at the corresponding edge areas of the notches 310 as the first images after focusing.

S506, transmitting the second wafer to the chuck with the determined wafer transmission sequence at the back, adjusting the first wafer to avoid the shooting path in the X-Y direction, and shooting a second image of the second wafer at the bonding position.

The wafer transferred later is used as a second wafer, a chuck with a preceding wafer transfer sequence is kept at a bonding position or is driven by a driving structure 200 to move away from the chuck with the succeeding wafer transfer sequence to an avoiding position according to requirements so as to ensure smooth wafer transfer of the chuck with the succeeding wafer transfer sequence, the chuck with the succeeding wafer transfer sequence can be kept in place after receiving the second wafer or can move along a Z direction under the driving of the driving structure 200 so as to reach the bonding position, when the wafer transfer sequence of the target chuck 300 is in the succeeding wafer transfer sequence, the vision system 500 is not blocked, the target chuck 300 and the carrying chuck 400 are kept in place in the X-Y direction so as to realize the shooting of a second image by the vision system 500, when the wafer transfer sequence of the carrying chuck 400 is in the succeeding wafer transfer sequence, a first wafer loaded on the target chuck 300 can block a notch 310, the driving assembly drives the target chuck 300 to move in a translation way in the X-Y direction so that the first wafer does not block a shooting area of the vision system 500, and the images of the corresponding edge areas of the second wafer are taken as the second image after focusing by the vision system 500.

S508, acquiring the circle center offset of the first wafer and the second wafer in the X-Y direction according to the first image and the second image.

And similarly, the outline of the edge area of the second wafer at different positions along the circumferential direction in each second image can be calculated according to the outline to obtain the second circle center coordinate of the second wafer, and the circle center offset of the first wafer and the second wafer on the X-Y plane can be calculated according to the first circle center coordinate and the second circle center coordinate.

S510, aligning the target chuck 300 and the bearing chuck 400 which are positioned at the bonding position according to the circle center offset.

S512 performs a bonding process on the first wafer and the second wafer.

The first wafer and the second wafer are located at the respective bonding positions, the driving structure 200 is controlled to drive the target chuck 300 and the carrier chuck 400 to relatively move along the X-Y direction according to the calculated circle center offset to perform offset compensation of corresponding displacement, so that translational alignment operation of the first wafer and the second wafer is realized, and then bonding processing is performed on the first wafer and the second wafer to obtain the bonded wafer.

In the wafer bonding device and the wafer bonding method provided by the embodiment, the plurality of vision systems 500 are arranged on one side of the target chuck 300, so that the vision systems 500 do not need to displace in the operation process, the target chuck 300 and the carrier chuck 400 do not need to displace or only do small-stroke lateral movement under the driving of the driving structure 200 so as to avoid the notch 310 positioned at the edge of the target chuck 300, the target chuck 300 and the carrier chuck 400 only need to do small-stroke lifting movement under the driving of the driving structure 200 in the Z direction so as to reach the bonding position or the avoidance position, and in the operation process, the displacement of the vision systems 500 and the driving components is small, the introduced error is small, thereby improving the accuracy of measuring the circle center offset, correspondingly improving the alignment accuracy and the bonding quality of the first bonding wafer and the second bonding wafer, simultaneously reducing the interaction time consumption in the operation process, improving the bonding efficiency and the yield, and the wafer bonding device with the small displacement of the target chuck 300 and the carrier chuck 400, and the wafer bonding device occupying only one bonding position in the X-Y direction, and the wafer bonding process space and the wafer bonding device are also capable of improving the bonding device.

Specifically, in the wafer bonding apparatus provided in this embodiment, the Z-displacement of the driving structure 200 to the target chuck 300 and the carrier chuck 400 is about 20mm, the lateral displacement is greater than the radial dimension of the notch 310 along the corresponding chuck, and the lateral displacement and the longitudinal displacement are both much smaller than the large-stroke displacement of about 500mm between the three process positions in the related art.

Specifically, in the embodiment, step S502 includes determining whether the target chuck 300 has the X-direction translational degree of freedom and/or the Y-direction translational degree of freedom according to the X-direction translational degree of freedom and the Y-direction translational degree of freedom of the target chuck 300, if so, determining that the transfer order of the target chuck 300 is located before the transfer order of the load chuck 400 or determining that the transfer order of the load chuck 400 is located before the transfer order of the target chuck 300, and if not, determining that the transfer order of the load chuck 400 is located before the transfer order of the target chuck 300.

When the target chuck 300 does not have the X-direction translational degree of freedom and the Y-direction translational degree of freedom, the target chuck 300 is relatively fixedly connected to the carrier 100, and if the target chuck 300 is loaded with wafers before the carrier chuck 400, the wafers loaded on the target chuck 300 will block the notch 310 and affect the vision system 500 to photograph the edge area of the wafers loaded on the carrier chuck 400 through the notch 310, so that under this condition, it is required to define that the transfer sequence of the target chuck 300 is located after the transfer sequence of the carrier chuck 400, so as to ensure that the vision system 500 photographs the wafers loaded on the target chuck 300 and the carrier chuck 400.

When the target chuck 300 has at least one of the X-direction translational degree of freedom and the Y-direction translational degree of freedom under the driving of the driving structure 200, the characterization target chuck 300 may perform translational motion relative to the vision system 500 under the driving of the driving structure 200, so as to avoid the photographing region of the vision system 500, thereby solving the problem of shielding the notch 310 by the wafer loaded on the target chuck 300.

Optionally, in this embodiment, the target chuck 300 has an X-direction translational degree of freedom and a Y-direction translational degree of freedom under the drive of the drive structure 200. On the one hand, when the wafer transfer sequence of the target chuck 300 and the carrier chuck 400 is not limited in operation, the applicability is higher, specifically, when the parallelism of the target chuck 300 and the carrier chuck 400 has reached the standard, the wafer transfer sequence of the carrier chuck 400 can be set to be earlier than the wafer transfer sequence of the target chuck 300, so that in the alignment process, the image of the first bonding wafer and the second bonding wafer can be shot by the vision system 500 without X-Y displacement of the target chuck 300, thereby further reducing the X-Y displacement of the target chuck 300 and the carrier chuck 400 in the operation process, correspondingly further improving the alignment accuracy and the bonding quality of the wafer bonding device, further reducing the time consumption and improving the bonding efficiency and the yield. When the parallelism of the target chuck 300 and the carrying chuck 400 needs to be detected, the transfer sequence of the target chuck 300 or the carrying chuck 400 can be determined according to the installation position of the parallelism detecting element, on the basis, shooting of the first image and the second image can be realized, and alignment operation and bonding operation can be correspondingly realized so as to ensure normal operation of the wafer bonding device.

On the other hand, when the transfer sequence of the target chuck 300 precedes the carrying chuck 400, after the first image is shot, the driving structure 200 can drive the target chuck 300 to sequentially move in the direction away from each notch 310 in the X-Y plane, and the first bonding wafer is enabled to avoid shielding the notches 310 through smaller lateral displacement, so that the lateral movement amount of the target chuck 300 and the carrying chuck 400 in the X-Y direction in the alignment process is further reduced, errors introduced by the driving structure 200 are correspondingly further reduced, the ground accuracy and bonding quality of the wafer bonding device are further improved, meanwhile, the occupation of the lateral volume of the wafer bonding device is further reduced, and the structural compactness of the wafer bonding device is further improved.

In this embodiment, when the transfer sequence of the target chuck 300 is located before the transfer sequence of the carrier chuck 400, the first wafer will form a barrier to the notch 310, which affects the photographing of the second wafer by the vision system 500, and correspondingly, the step of adjusting the first wafer in the X-Y direction to avoid the photographing path includes driving the target chuck 300 and the carrier chuck 400 to move relatively along the X-Y direction, so as to move the first wafer to a position avoiding the photographing path, thereby ensuring the photographing of the second wafer by the vision system 500 to obtain the second image.

Specifically, as shown in fig. 4, the wafer bonding apparatus includes three vision systems 500, and the three vision systems 500 are uniformly spaced around the circumference of the target chuck 300; the target chuck 300 is provided with six notches 310, the six notches 310 are uniformly distributed at intervals along the circumferential direction of the target chuck 300, wherein the three notches 310 serve as reserved openings, the three notches 310 are in one-to-one correspondence with the three vision systems 500, when the target chuck 300 receives a first wafer, no shielding exists between the first wafer and the vision systems 500, when the target chuck 300 is positioned at a bonding position, the vision systems 500 can take pictures of the edges of the first wafer through the corresponding notches 310 to obtain three groups of first images, the first images are fed back to a control component of a wafer bonding device, the control component can calculate the first center coordinates of the first wafer according to the edge profiles of the first wafer in the three groups of first images, then, the second wafer is transmitted to the bearing chuck 400, when the bearing chuck 400 is positioned at the bonding position, the first wafer causes shielding to the three notches 310, the three groups of vision systems 500 can not take pictures through the three notches 310, then the driving structure 200 can drive the target chuck 300 and the bearing chuck 400 to move in a relative translation way along the X-Y direction, so that the three vision systems 300 and the three vision systems are blocked by the corresponding to the first wafer 500 are not sequentially controlled by the vision systems 500, and the vision systems 500 are not in the corresponding to the corresponding vision systems in the first vision systems, and the vision systems 500 are not blocked by the corresponding vision systems in the first vision systems, and the vision systems are sequentially in the corresponding positions are not blocked by the second vision systems, and the vision systems 500 are not in the corresponding vision systems are in the position to take the corresponding vision systems, the control component can calculate the second center coordinates of the second wafer according to the edge contours of the second wafer in the three groups of second images, and then calculates the center offset of the first wafer and the second wafer on the X-Y plane according to the first center coordinates and the second center coordinates.

Specifically, the driving structure 200 can drive the target chuck 300 and the carrying chuck 400 to move away from each other along a straight line where the connecting lines of the gaps 310 and the circle centers of the target chuck 300 are located, and avoid the shooting paths of the corresponding vision system 500 through displacement amounts not larger than the depths of the gaps 310, so that on the basis of ensuring effective avoidance, the transverse driving displacement amount of the driving structure 200 is further reduced, errors introduced by the driving structure 200 are correspondingly further reduced, the alignment accuracy of the wafer bonding device is further improved, and the transverse volume of the wafer bonding device is further reduced.

When the transfer sequence of the load chuck 400 is located before the transfer sequence of the target chuck 300, the step of adjusting the first wafer to avoid the photographing path in the X-Y direction includes keeping the load chuck 400 stationary in the X-Y direction so as to avoid the photographing path in the X-Y direction. The first wafer is firstly transferred to the carrying chuck 400, the first wafer does not shade the notch 310 when the carrying chuck 400 is positioned at the bonding position, the driving structure 200 does not need to adjust the positions of the carrying chuck 400 and the target chuck 300 in the X-Y direction, the first wafer can be shot by the vision system 500 only by adjusting the Z-direction interval between the carrying chuck 400 and the target chuck 300 according to the Z-direction space required by the transfer of the second wafer by the manipulator, then the second wafer is transferred to the target chuck 300, the notch 310 is not shaded by the first wafer and the second wafer, the shooting of the second wafer by the vision system 500 can be realized without adjusting the positions of the carrying chuck 400 and the target chuck 300 in the X-Y plane, the alignment process is simpler, the interaction time is shorter, the error introduced by the driving structure 200 is smaller, and the wafer bonding device has higher efficiency and higher yield.

Alternatively, in this embodiment, one of the notches 310 corresponds to a notch position of a wafer loaded on the target chuck 300, and the driving structure 200 is configured to drive the target chuck 300 and the carrier chuck 400 to rotate about the Z-axis. Correspondingly, the wafer bonding method further comprises the steps of acquiring deflection amounts of the first wafer and the second wafer around the Z axis according to the first image and the second image, adjusting the target chuck 300 and the bearing chuck 400 which are positioned at the bonding position according to the deflection amounts, and performing bonding treatment on the first wafer and the second wafer.

The edge of the wafer is provided with notches for representing the circumferential directions of the target chuck 300 and the carrying chuck 400, when the target chuck 300 and the carrying chuck 400 receive the wafer, the notches of the wafer correspond to the positions of one notch 310, the vision system 500 can respectively obtain notch outlines of the first wafer and the second wafer in a group of first images and a group of second images shot through the notch 310, the control assembly can calculate and obtain circumferential angle offset of the first wafer and the second wafer according to the notch outlines of the first wafer and the notch outlines of the second wafer, so as to obtain the deflection of the first wafer and the second wafer around the Z axis, and continuously, when the first wafer and the second wafer are positioned at the bonding position, the driving structure 200 can adjust and compensate the circumferential offset of the first wafer and the second wafer according to the deflection, and can align the circumferential angles of the first wafer and the second wafer on the basis of not increasing operation steps, so that the alignment accuracy and the bonding quality of the wafer bonding device are further improved.

In this embodiment, one of the target chuck 300 and the carrier chuck 400 is relatively fixed to the carrier 100 along the Z direction, and the other is used as a lifting chuck, which has a translational degree of freedom along the Z direction under the driving of the driving structure 200, so that the lifting chuck needs to be lifted and moved to reach an initial position, a avoidance position or a bonding position under the driving of the lifting structure, and the initial position and the bonding position of the other chuck are the same position.

The step S504 of shooting a first image of a first wafer at a bonding position comprises the steps of judging whether a chuck for loading the first wafer has a Z-direction translational degree of freedom or not, if so, driving the chuck to move up and down along the Z-direction to the bonding position and shooting the first image of the first wafer, and if not, characterizing that the initial position of the chuck is the bonding position at the same time, and directly shooting the first image of the first wafer.

S506, shooting a second image of the second wafer at the bonding position is similar to the step of shooting a first image of the first wafer at the bonding position in S504, when the chuck loading the second wafer has the Z-direction translational degree of freedom, the chuck is driven to move up and down along the Z direction to the bonding position, and the second image of the second wafer is shot, when the chuck loading the second wafer does not have the Z-direction translational degree of freedom, the initial position representing the chuck is the bonding position at the same time, and the second image of the second wafer is shot directly.

Wherein, for the lift chuck with Z-direction translational freedom, the thimble structure corresponding to the lift chuck is relatively fixedly connected to the carrier 100. During the use, the position of thimble structure is fixed, can be through the relative thimble structure elevating movement of lift chuck to realize that the thimble structure stretches out the lift chuck in order to accept the wafer of transmission through the through-hole 40A of lift chuck along Z orientation, or in order to place the wafer of accepting in the lift chuck along Z orientation withdrawal lift chuck, thereby realize the receipt of thimble structure, lift chuck to the wafer through simpler structure.

Specifically, the driving structure 200 may adopt a hexapod displacement table, wherein a fixed end of the hexapod displacement table is fixedly connected to the carrier 100, and a moving end of the hexapod displacement table is connected to one of the chucks. The six-foot displacement platform has X-direction translational freedom degree, Y-direction translational freedom degree, Z-direction translational freedom degree, rotational freedom degree around the X axis, rotational freedom degree around the Y axis and rotational freedom degree around the Z axis, and the six groups of translation platforms can be used for adjusting the positions and angles of the target chuck 300 relative to the bearing chuck 400 in all directions, so that the alignment operation and the bonding operation of the wafer bonding device can be realized, and the six-foot displacement platform has a simple structure and strong functionality.

In this embodiment, as shown in fig. 1 and 2, the wafer bonding apparatus further includes a base 600, and the carrier 100 is connected to the base 600 through a vibration isolation assembly 700. When in use, the carrier 100 bears components such as the driving structure 200, the vision system 500, the target chuck 300, the bearing chuck 400 and the like for alignment and bonding, the base 600 is placed on the bottom surface or the base station, the carrier 100 is connected with the base 600 through the vibration isolation component 700, and the vibration isolation component 700 can effectively reduce vibration influence caused by operation of an external device on the carrier 100 and the components loaded by the carrier 100, thereby ensuring accuracy of alignment operation and bonding operation, and correspondingly further improving bonding quality of the wafer bonding device.

As shown in fig. 1 and 2, the driving structure 200 adopts a hexapod displacement table, the hexapod displacement table is connected to the carrier 100, and the top moving end of the hexapod displacement table is connected to the lower chuck, so that the lower chuck can be driven to move to have six degrees of freedom, the upper chuck is fixedly connected to the carrier 100, the vision systems 500 are three groups, the three groups of vision systems 500 are connected to the carrier 100 and are positioned below the lower chuck, the lower chuck is used as the target chuck 300 to be close to the vision system 500, the upper chuck is used as the bearing chuck 400 to be far away from the vision system 500, and the lower chuck is used as the lifting assembly to have Z-direction translational degrees of freedom. The ejector pin structure corresponding to the lower chuck is relatively and fixedly connected to the carrier 100 as a lower ejector pin structure 900, and the ejector pin structure corresponding to the upper chuck is as an upper ejector pin structure 810, and can be driven by the lifting component 820 to move up and down relative to the upper chuck through the through hole 40A of the upper chuck, so as to receive the upper wafer.

Specifically, each vision system 500 may include a focusing assembly 510 fixedly connected to the carrier 100 and a camera assembly 520 connected to the focusing assembly 510, where the camera assembly 520 may specifically include a camera, a light source and a lens, and the axial direction of the lens extends along the Z direction and corresponds to one of the gaps 310, where the camera assembly 520 may use visible light or infrared light, and when in use, the focusing assembly 510 may automatically focus the camera assembly 520 to capture an image of a lower wafer moving up and down to a bonding position and an image of an upper wafer holding at the bonding position.

The lifting component 820 and the focusing component 510 can specifically be an electric sliding table.

Fig. 6 is a schematic diagram of a second process of the wafer bonding method according to an embodiment of the present invention. When one of the notches corresponds to the notch position of the wafer, as shown in fig. 6, the wafer bonding method includes:

S601 judges whether the target chuck has X-direction translational freedom and/or Y-direction translational freedom, if so, step S602 or S603 is executed, and if not, step S603 is executed.

S602, determining that the transfer sequence of the target chuck is positioned before the transfer sequence of the bearing chuck, and continuing to execute step S604.

S603, determining that the transfer sequence of the carrying chuck is positioned before the transfer sequence of the target chuck, and continuing to execute step S606.

S604 transfers the first wafer to the target chuck and captures a first image of the first wafer at the bonding location.

S605, the second wafer is transmitted to the bearing chuck, the target chuck and the bearing chuck are driven to move relatively along the X-Y direction, so that the first wafer moves to a position avoiding the shooting path, a second image of the second wafer at the bonding position is shot, and step S608 is continued.

S606 transfers the first wafer to the carrier chuck and captures a first image of the first wafer at the bonding location.

S607, transferring the second wafer to the target chuck, keeping the bearing chuck fixed in the X-Y direction, so that the first wafer avoids the shooting path in the X-Y direction, shooting a second image of the second wafer at the bonding position, and continuing to execute step S608.

S608, acquiring the circle center offset of the first wafer and the second wafer in the X-Y direction and the deflection around the Z axis according to the first image and the second image.

S609, aligning the target chuck and the bearing chuck at the bonding position according to the circle center offset and the deflection around the Z axis.

S610 performs a bonding process on the first wafer and the second wafer.

Fig. 7 is a schematic diagram of a second process of a wafer bonding method according to an embodiment of the present invention. The wafer bonding method includes, as shown in fig. 1 and 2, setting three notches on a target chuck, setting vision systems below the lower chuck, using the lower chuck as the target chuck, using the upper chuck as the carrying chuck, and using the transfer order of the target chuck to be prior, wherein the upper chuck is relatively and fixedly connected to the carrying seat, the driving structure adopts six-foot displacement tables, and the six-group displacement tables are connected to the lower chuck, so that the lower chuck has an X-direction translational degree of freedom, a Y-direction translational degree of freedom and a Z-direction translational degree of freedom, and accordingly, the lower chuck is used as a lifting chuck, the target chuck is provided with the three notches, one notch corresponds to the notch of a wafer, the vision systems are three and are all arranged below the lower chuck, so that the lower chuck is used as the target chuck, and the upper chuck is used as the carrying chuck, and the transfer order of the target chuck is prior, as shown in fig. 7.

S701, determining that the transfer sequence of the target chuck is prior according to the X-direction translation freedom degree and the Y-direction translation freedom degree of the target chuck.

S702 transfers the first wafer to the target chuck.

S703, driving the target chuck to rise from the initial position to the bonding position, and shooting a first image of the first wafer.

S704, driving the target chuck to the bonding position to descend to the avoidance position, and transmitting the second wafer to the bearing chuck.

And S705, driving the target chuck to sequentially move along the direction deviating from the openings of the three notches, so that the first wafer sequentially avoids the shooting paths of the vision systems corresponding to the three notches, and the three vision systems which are avoided sequentially shoot the second image of the second wafer.

S706, acquiring the circle center offset of the first wafer and the second wafer in the X-Y direction and the deflection around the Z axis according to the first image and the second image.

S707, driving the target chuck to rise from the avoidance position to the bonding position, and adjusting the alignment target chuck and the bearing chuck according to the circle center offset and the deflection around the Z axis.

S708 performs a bonding process on the first wafer and the second wafer.

It should be noted that the above embodiments are merely for illustrating the technical solution of the present invention and not for limiting the same, and although the present invention has been described in detail with reference to the above embodiments, it should be understood by those skilled in the art that the technical solution described in the above embodiments may be modified or some or all of the technical features may be equivalently replaced, and these modifications or substitutions do not make the essence of the corresponding technical solution deviate from the scope of the technical solution of the embodiments of the present invention.

Claims (10)

1. The wafer bonding device is characterized by comprising a carrier seat (100), a driving structure (200) arranged on the carrier seat (100), and a target chuck (300) and a bearing chuck (400) which are arranged along the Z direction, wherein the target chuck (300) and/or the bearing chuck (400) are in transmission connection with the driving structure (200), and the driving structure (200) is configured to drive the target chuck (300) and the bearing chuck (400) to move relatively along the X-Y direction and the Z direction;

The wafer carrier comprises a carrier seat (100), a plurality of vision systems (500) and a plurality of carrier chucks (400), wherein the edges of the target chucks (300) are provided with a plurality of notches (310), the carrier seat (100) is provided with the plurality of vision systems (500), the plurality of vision systems (500) are positioned on one side, away from the carrier chucks (400), of the target chucks (300), the axial directions of the plurality of vision systems (500) are consistent with the Z direction and correspond to the plurality of notches (310) one by one, and the wafer carrier chucks (300) and the carrier chucks (400) are configured to shoot images corresponding to the notches (310).

2. The wafer bonding apparatus of claim 1, wherein the target chuck (300) has an X-translational degree of freedom and a Y-translational degree of freedom under the drive of the drive structure (200).

3. The wafer bonding apparatus of claim 1, wherein one of the notches (310) corresponds to a notch position of a wafer loaded on the target chuck (300), and the drive structure (200) is configured to drive relative rotation of the target chuck (300) and the carrier chuck (400) about a Z-axis.

4. The wafer bonding apparatus according to claim 1, wherein the target chuck (300) or the carrier chuck (400) is used as a lift chuck, the lift chuck has a Z-translation degree of freedom under the drive of the drive structure (200), and a thimble structure corresponding to the lift chuck is relatively fixedly connected to the carrier seat (100).

5. The wafer bonding apparatus according to claim 1, wherein the driving structure (200) comprises a hexapod displacement stage, a fixed end of the hexapod displacement stage is fixedly connected to the carrier (100), and a moving end of the hexapod displacement stage is connected to the target chuck (300) or the carrier chuck (400).

6. A wafer bonding method, characterized in that the wafer bonding apparatus according to claims 1 to 5 is employed, comprising:

determining a transfer sequence of the target chuck (300) and the bearing chuck (400) according to the X-direction translational freedom degree and the Y-direction translational freedom degree of the target chuck (300);

Transmitting a first wafer to a chuck with the determined wafer transmitting sequence in front, and shooting a first image of the first wafer positioned at a bonding position;

transmitting a second wafer to a chuck with a determined wafer transmission sequence at the back, adjusting the first wafer to avoid a shooting path in the X-Y direction, and shooting a second image of the second wafer at a bonding position;

acquiring the circle center offset of the first wafer and the second wafer in the X-Y direction according to the first image and the second image;

adjusting the target chuck (300) and the bearing chuck (400) which are positioned at the bonding position according to the circle center offset;

And carrying out bonding treatment on the first wafer and the second wafer.

7. The wafer bonding method according to claim 6, wherein the step of determining the transfer order of the target chuck (300) and the carrier chuck (400) according to the X-direction translational degree of freedom and the Y-direction translational degree of freedom of the target chuck (300) comprises:

judging whether the target chuck (300) has an X-direction translational degree of freedom and/or a Y-direction translational degree of freedom;

if yes, determining that the transfer sequence of the target chuck (300) is positioned before the transfer sequence of the bearing chuck (400), or determining that the transfer sequence of the bearing chuck (400) is positioned before the transfer sequence of the target chuck (300);

If not, determining that the transfer sequence of the carrying chuck (400) is positioned before the transfer sequence of the target chuck (300).

8. The wafer bonding method according to claim 7, wherein the step of adjusting the first wafer in the X-Y direction avoiding photographing path when the transfer order of the target chuck (300) is before the transfer order of the carrier chuck (400) comprises driving the target chuck (300) and the carrier chuck (400) to relatively move in the X-Y direction to move the first wafer to a position avoiding the photographing path;

when the wafer transfer sequence of the carrying chuck (400) is positioned before the wafer transfer sequence of the target chuck (300), the step of adjusting the first wafer to avoid the shooting path in the X-Y direction comprises the step of keeping the carrying chuck (400) fixed in the X-Y direction so as to enable the first wafer to avoid the shooting path in the X-Y direction.

9. The wafer bonding method according to claim 6, wherein the step of capturing a first image of the first wafer at the bonding location comprises:

Judging whether a chuck for loading the first wafer has a Z-direction translation degree of freedom;

if yes, driving the chuck to move up and down along the Z direction to a bonding position, and shooting a first image of the first wafer;

if not, directly shooting a first image of the first wafer.

10. The wafer bonding method according to claim 6, the wafer bonding method is characterized by further comprising the following steps:

Acquiring deflection amounts of the first wafer and the second wafer around a Z axis according to the first image and the second image;

the target chuck (300) and the carrier chuck (400) are aligned in a bonding position according to the deflection amount, and the step of bonding the first wafer and the second wafer is performed only after that.