An apparatus for wafer alignment and bonding

Abstract

This utility model relates to the field of wafer bonding technology, and particularly to a device for wafer alignment and bonding, comprising a pressing mechanism, a lifting mechanism, a positioning mechanism, a first robotic arm, a second robotic arm, a first camera, and a stage. The pressing mechanism is used to press together an upper wafer and a lower wafer to be bonded. A pre-pressing element is provided at the lower end of the pressing mechanism. The first robotic arm is used to transport the lower wafer to be bonded to the lifting mechanism and the upper wafer to be bonded to the positioning mechanism. The second robotic arm is used to transport the upper wafer to be bonded to the first camera. The first camera is used to photograph and record the coordinate position of the reference point of the upper wafer to be bonded on the second robotic arm. The pre-pressing element is used to pre-bond the upper and lower wafers, and then the positioning mechanism is withdrawn. Since the upper and lower wafers have already been partially bonded, the upper wafer will not slip and create dislocations between it and the lower wafer when the positioning mechanism is withdrawn, thereby improving alignment accuracy.

Description

Technical Field

[0001] This utility model relates to the field of wafer bonding technology, and in particular to a device for wafer alignment and bonding. Background Technology

[0002] With the development of the electronics industry, wafer bonding technology has enabled the stacking of devices with higher layers, thus attracting increasing attention. However, due to the relatively short history of wafer bonding equipment, it still has many shortcomings compared to other semiconductor equipment.

[0003] Chinese invention patent CN118824876A discloses a wafer bonding apparatus and method for use in a vacuum environment. The wafer bonding apparatus includes a pressure head, a first camera, a stage, a second camera, and a robotic arm. The pressure head is connected to a driving device and moves up and down under the action of the driving device. The pressure head is used to press two or more wafers to be bonded. The stage is located below the pressure head and is used to position and clamp the wafers to be bonded. The first camera is used to photograph the reference point of the wafers to be bonded on the stage and obtain the coordinate position of the reference point. The robotic arm is located on one side of the stage and is used to transport the wafers to the stage.

[0004] The second camera is positioned on the transport path of the wafer to be bonded. It is used to photograph the reference point of the wafer on the robotic arm and obtain its coordinates. However, when the suction cup of the second suction arm is withdrawn after placing the second wafer (i.e., the upper wafer), the upper wafer is prone to slipping, leading to reduced alignment accuracy between the upper and lower wafers and significantly decreasing the yield rate after bonding. Utility Model Content

[0005] In order to solve the above-mentioned technical problems existing in the prior art, the present invention provides a device for wafer alignment and bonding.

[0006] The technical solution of this utility model to solve the above-mentioned technical problems is as follows:

[0007] This utility model provides a device for wafer alignment and bonding, including a drive mechanism, a lifting mechanism, a positioning mechanism, a pressing mechanism, a first robotic arm, a second robotic arm, a first camera, and a stage. The pressing mechanism is connected to the drive mechanism and is lifted and lowered under the action of the drive mechanism. The pressing mechanism is used to press the upper and lower wafers to be bonded together. A pre-pressing component is provided at the lower end of the pressing mechanism. The stage is located below the pressing mechanism and is used to clamp the lower wafer to be bonded. The first robotic arm, the second robotic arm, and the first camera are all located on the side of the stage. The first robotic arm is used to transport the lower wafer to be bonded to the lifting mechanism and the upper wafer to be bonded to the positioning mechanism. The second robotic arm is used to transport the upper wafer to be bonded to the first camera. The first camera is used to photograph the reference point of the upper wafer to be bonded on the second robotic arm and record the coordinate position of the reference point.

[0008] The device for wafer alignment and bonding provided by this utility model first uses a pre-pressing component to pre-bond the upper and lower wafers to be bonded, and then the positioning mechanism is withdrawn outward. Since the upper and lower wafers have been partially bonded, the upper wafer will not slide and generate dislocations between it and the lower wafer when the positioning mechanism is withdrawn, thereby improving the alignment accuracy.

[0009] Based on the above technical solution, the present invention can also be improved in the following ways:

[0010] Furthermore, it also includes a vacuum chamber, with the first robotic arm, the second robotic arm, and the first camera all located outside the vacuum chamber, and the pressing mechanism and the stage all located inside the vacuum chamber.

[0011] Furthermore, the vacuum chamber includes an upper chamber and a lower chamber, the upper chamber being connected to a lifting mechanism and moving up and down under the action of the lifting mechanism.

[0012] Furthermore, it also includes a second camera and a third camera, used to photograph the reference point of the under-wafer to be bonded and record the coordinate position of the reference point.

[0013] Furthermore, the second and third cameras move horizontally inside and outside the vacuum chamber.

[0014] Furthermore, the positioning mechanism can be close to or far from the platform.

[0015] Furthermore, it also includes a base, on which both the lifting mechanism and the positioning mechanism are mounted, with the lifting mechanism located inside the positioning mechanism.

[0016] Furthermore, the pressing mechanism is provided with a first heating component, and the platform is provided with a second heating component.

[0017] Furthermore, the pre-compression component is located at the center of the lower end of the pressing mechanism.

[0018] The beneficial effect of adopting the above-mentioned further technical solution is that it enables pre-bonding of the center parts of the upper and lower wafers, thereby improving alignment accuracy.

[0019] Furthermore, the pre-compression component is a pre-compression pin, and the pre-compression pin contains a compression spring.

[0020] The beneficial effect of adopting the above-mentioned further technical solution is that by setting a compression spring inside the pre-compression pin, the pre-compression pin can be automatically ejected.

[0021] Compared with the prior art, the present invention has the following technical effects:

[0022] The device for wafer alignment and bonding provided by this utility model first uses a pre-pressing component to pre-bond the upper and lower wafers to be bonded, and then the positioning mechanism is withdrawn outward. Since the upper and lower wafers have been partially bonded, the upper wafer will not slide and generate dislocations between it and the lower wafer when the positioning mechanism is withdrawn, thereby improving the alignment accuracy. Attached Figure Description

[0023] Figure 1 This diagram illustrates the structure of a device for wafer alignment and bonding according to an embodiment of the present invention.

[0024] Figure 2 The diagram shows the structure of the second and third cameras;

[0025] Figure 3 A schematic diagram of the pre-compression component is shown;

[0026] Figure 4 A schematic diagram showing the compression spring within the pressing mechanism is shown;

[0027] Figure label:

[0028] 1. Drive mechanism; 2. Upper chamber; 3. Pressing mechanism; 4. First robotic arm; 5. Second robotic arm; 6. First camera; 7. Lower chamber; 8. Positioning mechanism; 9. Lifting mechanism; 10. Base; 11. Second camera; 12. Third camera; 13. Lower wafer; 14. Upper wafer; 15. Stage; 16. Pre-pressing component; 17. Compression spring. Detailed Implementation

[0029] The following specific embodiments illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. Although the description of this utility model will be presented in conjunction with preferred embodiments, this does not mean that the features of this utility model are limited to this embodiment. On the contrary, the purpose of describing the utility model in conjunction with the embodiments is to cover other options or modifications that may be derived based on the claims of this utility model. To provide a deep understanding of this utility model, many specific details will be included in the following description. This utility model may also be implemented without using these details. Furthermore, to avoid confusion or obscuring the focus of this utility model, some specific details will be omitted in the description. It should be noted that, without conflict, the embodiments and features in the embodiments of this utility model can be combined with each other.

[0030] See Figures 1 to 4 An apparatus for wafer alignment and bonding includes a drive mechanism 1, a lifting mechanism 9, a positioning mechanism 8, a pressing mechanism 3, a first robotic arm 4, a second robotic arm 5, a first camera 6, a stage 15, a vacuum chamber, a second camera 11, a third camera 12, and a base 10. The pressing mechanism 3 is connected to the drive mechanism 1 and is lifted and lowered under the action of the drive mechanism 1. The pressing mechanism 3 is used to press the upper wafer 14 and the lower wafer 13 to be bonded. A pre-pressing component 16 is provided at the lower end of the pressing mechanism 3. The stage 15 is located below the pressing mechanism 3 and is used to clamp the lower wafer 13 to be bonded. The first robotic arm 4, the second robotic arm 5, and the first camera 6 are all located on the stage. On the side of stage 15, the first robotic arm 4 is used to transport the lower wafer 13 to be bonded to the lifting mechanism 9 and the upper wafer 14 to be bonded to the positioning mechanism 8. The second robotic arm 5 is used to transport the upper wafer 14 to be bonded to the first camera 6. The first camera 6 is used to take pictures of the reference point of the upper wafer 14 to be bonded on the second robotic arm 5 and record the coordinate position of the reference point. The second camera 11 and the third camera 12 are used to take pictures of the reference point of the lower wafer 13 to be bonded and record the coordinate position of the reference point. The second camera 11 and the third camera 12 can move horizontally inside and outside the vacuum chamber, and can move closer to or further away from the lower wafer 13 placed on the stage 15.

[0031] The pre-pressing component 16 is located at the center of the lower end of the pressing mechanism 3. Preferably, the pre-pressing component 16 is a pre-pressing pin, and the pre-pressing pin has a compression spring 17 inside. When the pre-pressing is completed, as the pressing mechanism 3 continues to descend, the pre-pressing component 16 is pressed into the pressing mechanism 3 under the action of the compression spring 17. When the upper wafer 14 and the lower wafer 13 are bonded, the pressing mechanism 3 rises under the action of the driving mechanism 1, and the pre-pressing component 16 pops out.

[0032] The first robotic arm 4, the second robotic arm 5, and the first camera 6 are all located outside the vacuum chamber, while the pressing mechanism 3 and the stage 15 are all located inside the vacuum chamber. The vacuum chamber includes an upper chamber 2 and a lower chamber 7. The upper chamber 2 is connected to the lifting mechanism and is raised and lowered under the action of the lifting mechanism. Preferably, the lifting mechanism is a cylinder.

[0033] The base 10 is located below the lower chamber 7. The lifting mechanism 9 and the positioning mechanism 8 are both disposed on the base 10, with the lifting mechanism 9 located inside the positioning mechanism 8. Both the lifting mechanism 9 and the positioning mechanism 8 extend vertically. The positioning mechanism 8 can move closer to or further away from the stage 15 in the horizontal direction. When the positioning mechanism 8 is close to the stage 15, the distance between the positioning mechanism 8 and the edge of the lower wafer 13 clamped on the stage 15 is within 3mm, so that the first robot arm 4 can subsequently transport the upper wafer 14 to be bonded to the positioning mechanism 8. When the upper wafer 14 is transported to the positioning mechanism 8, it is located above the lower wafer 13. Under the obstruction of the positioning mechanism 8, the upper wafer 14 and the lower wafer 13 are spaced apart and will not contact each other.

[0034] The lifting mechanism 9 includes two first loading platforms that are spaced apart and evenly arranged, and the positioning mechanism 8 includes two second loading platforms that are spaced apart and evenly arranged. The two first loading platforms are used to place the lower wafer 13, and the two second loading platforms are used to place the upper wafer 14, thereby achieving stable support for the lower wafer 13 and the upper wafer 14 respectively.

[0035] The pressing mechanism 3 is provided with a first heating component, and the stage 15 is provided with a second heating component. The first heating component and the second heating component are used to heat the vacuum chamber to achieve bonding between the upper wafer 14 and the lower wafer 13.

[0036] The process of aligning and bonding the upper wafer 14 and the lower wafer 13 in a vacuum chamber using the wafer alignment and bonding device provided by this utility model is as follows: First, the upper chamber 2 is lifted by the lifting mechanism, opening the upper chamber 2 and the lower chamber 7. Then, the lifting mechanism 9 rises, and the first robotic arm 4 removes a wafer to be bonded from the wafer carrier as the lower wafer 13 and places the lower wafer 13 on the two first loading platforms of the lifting mechanism 9. Subsequently, the lifting mechanism 9 lowers the lower wafer 13 and places it on the loading stage 15, which clamps the lower wafer 13 to be bonded. Afterward, the positioning mechanism 8 extends, that is, the positioning mechanism 8 approaches the loading stage 15 in the horizontal direction, so that the two second loading platforms are close to the edge of the lower wafer 13. The distance is less than 3mm; then, the second camera 11 and the third camera 12 move horizontally from outside the vacuum chamber to inside the vacuum chamber, thus approaching the lower wafer 13 placed on the stage 15. The second camera 11 and the third camera 12 photograph the reference point of the lower wafer 13 and record the coordinate position of the reference point, thus confirming the accurate position of the lower wafer 13. Then, the second camera 11 and the third camera 12 move horizontally away from the stage 15 and move to outside the vacuum chamber; then, the first robot arm 4 takes out a wafer to be bonded from the wafer carrier as the upper wafer 14 and places the upper wafer 14 on the two second carrying platforms of the positioning mechanism 8. At this time, the upper wafer 14 is located above the lower wafer 13, because The positioning mechanism 8 isolates the upper wafer 14 from the lower wafer 13, preventing them from contacting. Subsequently, the second robotic arm 5 removes the upper wafer 14 and moves it to the first camera 6. The first camera 6 photographs the reference point of the upper wafer 14 on the second robotic arm 5 and records its coordinates, thus confirming the position of the upper wafer 14. Based on the position of the lower wafer 13, the position and angle of the upper wafer 14 are finely adjusted. After adjustment, the second robotic arm 5 moves the upper wafer 14 into the vacuum chamber, where it rests on the two second loading platforms of the positioning mechanism 8. Then, the second robotic arm 5 withdraws from the vacuum chamber. Under the action of the lifting mechanism, the upper chamber 2 descends, closing with the lower chamber 7, forming a sealed vacuum chamber. The vacuum chamber is evacuated to the pressure value required for the process. Then, the bonding mechanism 3 descends under the action of the drive mechanism 1. After the pre-pressed component 16 contacts the upper wafer 14, the bonding mechanism 3 continues to descend a certain height, causing pre-bonding to occur at the center of the upper wafer 14 and the lower wafer 13. At this point, the bonding mechanism 3 stops descending, the two second carrier platforms of the positioning mechanism 8 are withdrawn, and the positioning mechanism 8 moves horizontally away from the carrier stage 15. The bonding mechanism 3 continues to descend to the pressure value required for the bonding process. The first heating component and the second heating component are turned on, heating to the process temperature required for bonding and holding for a certain time to perform the bonding process between the upper wafer 14 and the lower wafer 13. After bonding is completed, the bonding mechanism 3 rises to the initial position.After the wafer cooling is complete, the vacuum chamber is de-vacuumed to atmospheric pressure. The lifting mechanism 9 rises to lift the bonded wafer pair, and the first robotic arm 4 transfers them outside the vacuum chamber, thus completing the entire wafer alignment and bonding process.

[0037] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. An apparatus for wafer alignment and bonding, comprising: The system includes a drive mechanism (1), a lifting mechanism (9), a positioning mechanism (8), a pressing mechanism (3), a first robotic arm (4), a second robotic arm (5), a first camera (6), and a stage (15). The pressing mechanism (3) is connected to the drive mechanism (1) and is lifted and lowered under the action of the drive mechanism (1). The pressing mechanism (3) is used to press the upper wafer (14) and the lower wafer (13) to be bonded. A pre-pressing component (16) is provided at the lower end of the pressing mechanism (3). The stage (15) is located below the pressing mechanism (3) and is used to clamp the wafers to be bonded. The lower wafer (13) is located on the side of the stage (15). The first robotic arm (4), the second robotic arm (5), and the first camera (6) are all located on the side of the stage (15). The first robotic arm (4) is used to transport the lower wafer (13) to be bonded to the lifting mechanism (9) and to transport the upper wafer (14) to be bonded to the positioning mechanism (8). The second robotic arm (5) is used to transport the upper wafer (14) to be bonded to the first camera (6). The first camera (6) is used to take pictures of the reference point of the upper wafer (14) to be bonded on the second robotic arm (5) and record the coordinate position of the reference point.

2. The apparatus for wafer alignment and bonding of claim 1, wherein, It also includes a vacuum chamber, with the first robotic arm (4), the second robotic arm (5), and the first camera (6) located outside the vacuum chamber, and the pressing mechanism (3) and the stage (15) located inside the vacuum chamber.

3. The apparatus for wafer alignment and bonding of claim 2, wherein, The vacuum chamber includes an upper chamber (2) and a lower chamber (7). The upper chamber (2) is connected to a lifting mechanism and moves up and down under the action of the lifting mechanism.

4. The apparatus for wafer alignment and bonding of claim 2, wherein, It also includes a second camera (11) and a third camera (12) for taking pictures of the reference point of the lower wafer (13) to be bonded and recording the coordinate position of the reference point.

5. The apparatus for wafer alignment and bonding of claim 4, wherein, The second camera (11) and the third camera (12) move horizontally inside and outside the vacuum chamber.

6. The apparatus for wafer alignment and bonding according to any one of claims 1 to 5, wherein, The positioning mechanism (8) can be close to or away from the platform (15).

7. The apparatus for wafer alignment and bonding of claim 6, wherein, It also includes a base (10), and the lifting mechanism (9) and the positioning mechanism (8) are both disposed on the base (10), and the lifting mechanism (9) is located inside the positioning mechanism (8).

8. The apparatus for wafer alignment and bonding of claim 1, wherein, The pressing mechanism (3) is provided with a first heating component, and the stage (15) is provided with a second heating component.

9. The apparatus for wafer alignment and bonding of claim 1, wherein, The pre-pressing component (16) is located at the center of the lower end of the pressing mechanism (3).

10. The apparatus for wafer alignment and bonding of claim 9, wherein, The pre-compression component (16) is a pre-compression pin, and the pre-compression pin has a compression spring inside.

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