Wafer processing method and wafer processing device

Abstract

The invention relates to a wafer processing method and a wafer processing apparatus. The wafer taking method is used for clamping a wafer from a vacuum chuck, and comprises the following steps of: I, moving the wafer parallel to the contact surface of the wafer and the vacuum chuck by using a manipulator so as to reduce the area of a water film between the wafer and the vacuum chuck; step II, enabling the wafer to be far away from the vacuum chuck, and cutting off the water film; and step III, taking away the wafer. The water film tension is effectively reduced when the wafer is clamped from the vacuum chuck, and the polishing manipulator and the wafer can be protected.

Description

[0001] This application is a divisional application of the invention application with the application number 202411959834.5 and the title "Wafer Processing Method and Wafer Processing Apparatus" filed on December 30, 2024. Technical Field

[0002] The present invention relates to the field of semiconductor manufacturing; more specifically, the present invention relates to a wafer processing method and a wafer processing apparatus. Background Art

[0003] The thinning process of a wafer in a thinning equipment station is as follows: The wafer is transported by a transfer component to a grinding module, and after being ground and thinned, it is then transported by the transfer component and picked up by a manipulator, and transferred to the next station. The transfer component can be a vacuum chuck to adsorb the wafer, and the manipulator can be a jaw to grip and transport.

[0004] During the process of the wafer being returned after thinning, a cleaning operation is performed on the back of the wafer. After cleaning, a water film adheres to the back of the wafer, and a tension is generated between the water film and the chuck of the transfer component. When the manipulator grips and lifts the wafer, the water film tension will be broken, resulting in a phenomenon of vibration and tremor. The irregular vibration of the manipulator makes the contact part between the wafer and the jaw prone to damage, and has a greater impact on the life of the manipulator jaw. Summary of the Invention

[0005] In view of this, the present invention provides a wafer picking method, a wafer conveying method, a wafer processing method, a wafer transfer apparatus, and a wafer processing apparatus, thereby solving or at least alleviating one or more of the above problems and other problems existing in the prior art.

[0006] To achieve the foregoing object, a first aspect of the present invention provides a wafer picking method, which uses the jaws of a manipulator to pick up a wafer from a vacuum chuck. Wherein, the method includes the following steps:

[0007] Step I: Move the wafer parallel to the contact surface between the wafer and the vacuum chuck using the manipulator to reduce the area of the water film between the wafer and the vacuum chuck;

[0008] Step II: Move the wafer away from the vacuum chuck to break the water film;

[0009] Step III: Take away the wafer;

[0010] In the Step I, moving the wafer parallel to the contact surface between the wafer and the vacuum chuck includes: translating or swinging the wafer parallel to the contact surface between the wafer and the vacuum chuck;

[0011] The method further includes: before step I, using the manipulator to carry the wafer, moving the wafer vertically away from the vacuum chuck by a distance of 200 μm to 400 μm, and the water film does not break within this distance; in step I, distributing gas to the wafer via the vacuum chuck, the gas evaporates the water to assist in reducing the area of the water film, and according to the distribution amount and distribution speed of the gas, decomposes the liquid tension and gradually and uniformly reduces the area of the water film.

[0012] In the method as described above, optionally, during step I, detect whether the overlapping area or the water film area between the wafer and the vacuum chuck is less than a preset value: when it is less than the preset value, proceed to step II; when it is greater than or equal to the preset value, return to step I.

[0013] In the method as described above, optionally, the distance is 300 μm.

[0014] In the method as described above, optionally, in step I, moving the wafer parallel to the contact surface between the wafer and the vacuum chuck includes: rotating the wafer during the process of translating or swinging the wafer parallel to the contact surface between the wafer and the vacuum chuck.

[0015] In the method as described above, optionally, the vacuum chuck is made of porous ceramic material, and gas is distributed by the porous ceramic material.

[0016] In the method as described above, optionally, in step II, translate, rotate or swing the wafer parallel to the contact surface between the wafer and the vacuum chuck, so that the wafer moves away from the vacuum chuck and the water film is broken.

[0017] In the method as described above, optionally, the manipulator includes a first set of jaws and a second set of jaws, the first set of jaws includes a first jaw and a second jaw arranged side by side, the second set of jaws includes a third jaw and a fourth jaw arranged side by side, and the first set of jaws and the second set of jaws can move relative to each other to clamp and carry the wafer.

[0018] In the method as described above, optionally, the second set of jaws is controlled by a pressure cylinder, and the pressure cylinder is an oil cylinder or a pneumatic cylinder.

[0019] To achieve the foregoing object, a second aspect of the present invention provides a wafer conveying method applied to a wafer processing apparatus, wherein the wafer conveying method includes a step of using a manipulator to pick up a wafer from a vacuum chuck, and wherein the manipulator picks up the wafer from the vacuum chuck by the method described in any one of the foregoing first aspects.

[0020] In the method described above, optionally, the wafer processing apparatus includes a grinding module, a polishing module, and a transfer assembly between the grinding module and the polishing module. The transfer assembly includes the vacuum chuck, and the robot is the polishing robot of the polishing module. The polishing robot is configured to transfer the wafer from the transfer assembly to the polishing module.

[0021] To achieve the foregoing object, a third aspect of the present invention provides a wafer processing method, including: grinding a wafer using a grinding module of a wafer processing apparatus; transferring the ground wafer to a polishing module of the wafer processing apparatus using the wafer transfer method described in any of the foregoing aspects; and polishing the wafer using the polishing module.

[0022] To achieve the foregoing object, another aspect of the present invention provides a wafer transfer apparatus, wherein the wafer transfer apparatus includes:

[0023] a vacuum chuck configured to receive a wafer;

[0024] a transfer mechanism configured to pick up the wafer from the vacuum chuck by the method described in any of the foregoing first aspects.

[0025] In the wafer transfer apparatus described above, optionally, the wafer transfer apparatus further includes a controller connected to the transfer mechanism. An execution program is built in the controller, and the controller is configured to run the execution program to control the transfer mechanism to execute the method.

[0026] To achieve the foregoing object, another aspect of the present invention provides a wafer processing apparatus, wherein the wafer processing apparatus includes a grinding module, a polishing module, and a transfer assembly between the grinding module and the polishing module. The transfer assembly includes the vacuum chuck, and the polishing module includes a polishing robot. The polishing robot is configured to transfer the wafer from the transfer assembly to the polishing module, and the polishing robot picks up the wafer from the vacuum chuck by the method described in any of the foregoing first aspects.

[0027] To achieve the foregoing object, another aspect of the present invention provides a computer storage medium, on which a computer program is stored. When the program is executed by a processor, the method described in any of the foregoing aspects is implemented.

[0028] Some technical solutions of the present invention effectively reduce the water film tension and alleviate the vibration and jitter at the end of the chuck of the polishing robot.

[0029] Some technical solutions of the present invention can further effectively reduce the scratches generated between the wafer and the polishing robot due to relative movement.

[0030] Some technical solutions of the present invention can further effectively extend the service life of the jaws of the manipulator. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Referring to the accompanying drawings, the disclosure of the present invention will become more apparent. It should be understood that these drawings are for illustrative purposes only and are not intended to limit the scope of protection of the present invention. In the figures:

[0032] Figure 1 shows a schematic plan view of a wafer processing apparatus.

[0033] Figure 2 shows a top view schematic of the polishing manipulator jaws in a wafer processing apparatus, and at the same time shows the vacuum chuck and the wafer of the transfer assembly in a first positional relationship.

[0034] Figure 3 schematically shows Figure 2 the water film between the wafer and the vacuum chuck of the transfer assembly in

[0035] Figure 4 shows a top view schematic of the polishing manipulator jaws in a wafer processing apparatus, and at the same time shows the vacuum chuck and the wafer of the transfer assembly in a second positional relationship.

[0036] Figure 5 schematically shows Figure 4 the water film between the wafer and the suction cup of the transfer assembly in

[0037] Figure 6 shows a top view schematic of the polishing manipulator jaws in a wafer processing apparatus, and at the same time shows the vacuum chuck and the wafer of the transfer assembly in a third positional relationship.

[0038] Figure 7 shows a schematic flow chart of an embodiment of a wafer pick-up method according to the present invention.

[0039] Reference numerals: 1 - vacuum chuck; 2 - wafer; 3 - water film; 4 - manipulator; 5 - first set of jaws; 6 - second set of jaws; 7 - first jaw; 8 - second jaw; 9 - third jaw; 10 - fourth jaw; 20 - wafer processing apparatus; 21 - grinding module; 22 - polishing module; 23 - CMP and cleaning module; 24 - equipment front end module; 25 - wafer storage unit; 26 - first transfer unit; 27 - second transfer unit; 28 - third transfer unit; 29 - chemical mechanical polishing unit; 30 - post-processing unit; 31 - temporary storage part; 32 - mobile buffer part; 33 - polishing manipulator; 34 - grinding unit; 35 - cleaning unit; 36 - fourth transfer unit; 37 - base; 38 - workbench; 39 - suction cup; 41 - loading and unloading station; 42 - grinding manipulator; 43 - cleaning device. DETAILED DESCRIPTION OF THE INVENTION

[0040] With reference to the accompanying drawings and specific embodiments, the wafer picking method, wafer conveying method, wafer transfer device, and structure, composition, characteristics, and advantages of the wafer processing device of the present invention will be described by way of example below. However, all descriptions should not be used to form any limitation to the present invention.

[0041] For any single technical feature described or implied in the embodiments mentioned herein, or any single technical feature shown or implied in the respective drawings, the present invention still allows any combination or deletion to continue between these technical features (or their equivalents) without any technical obstacles. Therefore, it should be considered that these additional embodiments according to the present invention are also within the scope of the present disclosure.

[0042] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features.

[0043] In this application, a wafer may also be referred to as a chip, silicon wafer, substrate, or base plate, etc., and their meanings and actual functions are equivalent.

[0044] The wafer processing device provided by the embodiments of the present disclosure is mainly applied to the back thinning of wafers, such as a wafer thinning device or a wafer thinning and polishing integrated machine. Here, the back side refers to the side of the wafer without devices laid, generally the substrate, and the substrate material may be silicon, silicon oxide, silicon nitride, silicon carbide, sapphire, etc.

[0045] Figure 1 A schematic plan view of the wafer processing device is shown.

[0046] As shown in the figure, the wafer processing device 20 includes an equipment front-end module 24 (EFEM module), a CMP and cleaning module 23, a grinding module 21, etc. The CMP and cleaning module 23 specifically includes a polishing module 22, etc., where CMP represents chemical mechanical polishing.

[0047] The equipment front-end module 24 is used to realize the entry and exit of wafers, and the equipment front-end module 24 is arranged at the front end of the wafer processing device 20. The equipment front-end module 24 is a transition module for transferring wafers from the outside to the inside of the equipment machine table, used to realize the entry and exit of wafers to achieve "dry entry and dry exit" of wafers.

[0048] The grinding module 21 is used to grind and thin the wafers. The grinding may include rough grinding and fine grinding, and the grinding module 21 is arranged at the end of the wafer processing device 20.

[0049] The polishing module 22 is used to perform chemical mechanical polishing on the wafer after the grinding is completed, and also has the function of transferring the wafer between these three modules (the equipment front-end module 24, the grinding module 21, and the polishing module 22). The polishing module 22 is arranged between the equipment front-end module 24 and the grinding module 21.

[0050] It can be understood that Figure 1 The illustrated wafer processing apparatus is only an example. In other implementation manners, the polishing module 22 can also be omitted, and only the equipment front-end module 24 and the grinding module 21 are retained. In addition, the grinding module 21 can also include multiple grinding processes, such as 3, 4, 5, etc. As long as these similar modified embodiments can achieve the grinding and thinning of the wafer, they should all fall within the protection scope of this application.

[0051] The equipment front-end module 24 includes a wafer storage unit 25 and a first transfer unit 26. The wafer storage unit 25 is arranged on the front side of the wafer processing apparatus 20, and the first transfer unit 26 is arranged between the wafer storage unit 25 and the polishing module 22 to realize the transfer of the wafer between the wafer storage unit 25 and the polishing module 22.

[0052] The first transfer unit 26 can include a pick-and-place manipulator. The pick-and-place manipulator can rotate, extend, or fold and contract, and can also move along the transfer track. Here, the pick-and-place manipulator is a dry manipulator for picking and placing dry and clean wafers. The pick-and-place manipulator can take out the wafer to be processed from the wafer storage unit 25 and send it into the polishing module 22, and can also receive the processed wafer from the polishing module 22 and put it into the wafer storage unit 25.

[0053] The polishing module 22 can include a second transfer unit 27, a third transfer unit 28, a chemical mechanical polishing unit 29, and a post-processing unit 30. The second transfer unit 27, the chemical mechanical polishing unit 29, and the post-processing unit 30 respectively occupy the edges of the polishing module 22, and the third transfer unit 28 is located in the center.

[0054] Specifically, the second transfer unit 27 is located on one of the edges in the polishing module 22 and is distributed along the length direction of the device, and can communicate with the front-end module 24 and the grinding module 21 of the device. The chemical mechanical polishing unit 29 is located on the other edge of the polishing module 22 and is adjacent to the grinding module 21 and the second transfer unit 27 respectively. The post-processing unit 30 is located on yet another edge of the polishing module 22 and is adjacent to the front-end module 24, the second transfer unit 27, and the chemical mechanical polishing unit 29 respectively. The third transfer unit 28 is close to the center of the polishing module 22 and is surrounded by the second transfer unit 27, the chemical mechanical polishing unit 29, and the post-processing unit 30, and is used to realize the mutual transfer of wafers between the second transfer unit 27, the chemical mechanical polishing unit 29, and the post-processing unit 30. In the illustrated embodiment, the second transfer unit 27 may include a staging unit 31 and a moving buffer unit 32 for staging wafers and transporting wafers. The staging unit 31 is arranged at a position adjacent to the front-end module 24 of the device for staging or transferring wafers. The moving buffer unit 32 is arranged along the direction from the front-end module 24 to the grinding module 21 and can move bidirectionally.

[0055] In the illustrated embodiment, the third transfer unit 28 includes a polishing robot 33, and the polishing robot 33 is used to transfer the ground wafers from the moving buffer unit 32 to the chemical mechanical polishing unit 29, transfer the polished wafers from the chemical mechanical polishing unit 29 to the post-processing unit 30, and transfer the cleaned wafers from the post-processing unit 30 to the staging unit 31.

[0056] After the wafers are taken out from the front-end module 24 of the device, they are transported to the grinding module 21 via the second transfer unit 27 for grinding; after the wafers are ground in the grinding module 21, they are transported to the chemical mechanical polishing unit 29 via the second transfer unit 27 and the third transfer unit 28 for polishing; after polishing and cleaning are completed, the wafers are then transported back to the front-end module 24 of the device via the third transfer unit 28 and the second transfer unit 27.

[0057] The post-processing unit 30 is used to clean and dry the polished wafers and may include a horizontal brushing device and a single-chamber cleaning device.

[0058] The grinding module 21 may include a grinding unit 34, a cleaning unit 35, and a fourth transfer unit 36. The grinding unit 34 is used to realize wafer grinding and thickness measurement. As Figure 1 shown, the grinding unit 34 includes a base 37, a workbench 38 mounted on the base 37, a chuck 39 arranged on the workbench 38, and a grinding wheel corresponding to the position of the chuck 39. The workbench 38 is used to carry the wafers and can rotate around its vertical central axis. As Figure 1 shown, in one embodiment, there are three chucks 39, which can rotate among the rough grinding station, the fine grinding station, and the loading and unloading station 41.

[0059] Two grinding wheels respectively perform rough grinding and fine grinding. It can be understood that Figure 1 This is only an example, and the number of the suction cups 39 and grinding wheels can also be other values. The cleaning unit 35 is used to clean the suction cups 39, perform grinding, and clean the wafers. The fourth transfer unit 36 includes a grinding manipulator 42 for transferring wafers. The grinding manipulator 42 refers to the manipulator used in the grinding module 21 and is used to transfer wafers between the grinding unit 34 and the second transfer unit 27. Specifically, it is used to transfer wafers between the suction cups 39 corresponding to the loading and unloading station 41 and the mobile buffer 32. The grinding manipulator 42 picks up a wafer from the mobile buffer 32 of the second transfer unit 27 and sends it into the grinding unit 34 for grinding. After grinding and cleaning are completed, the grinding manipulator 42 picks up the wafer from the grinding unit 34 and then places it on the mobile buffer 32 for subsequent transfer of the wafer. The grinding manipulator 42 is internally provided with a pipeline that can be evacuated to achieve vacuum adsorption of the wafer. Alternatively, the grinding manipulator 42 can also be implemented by a mechanism with jaws. In one embodiment, the grinding manipulator 42 can also drive the wafer to rotate.

[0060] As Figure 1 shown, in one embodiment of the present invention, the grinding module 21 further includes a cleaning device 43. The cleaning device 43 is installed on the base 37 of the grinding module 21, beside the workbench 38 and on the moving track of the grinding manipulator 42, and is used to clean the bottom surface of the wafer after grinding during the process of the grinding manipulator 42 transferring the wafer.

[0061] Figure 2 shows a top view schematic diagram of the chuck of the polishing manipulator in the wafer processing device, and at the same time shows the vacuum suction cup 1 and the wafer 2 of the transfer assembly in the first positional relationship.

[0062] wherein the transfer assembly can be, for example, the second transfer unit 27. The vacuum suction cup 1 of the transfer assembly in this figure can be Figure 1 the suction cup on the second transfer unit 27 of the wafer processing device 20 in Figure 1 and the manipulator 4 can be

[0063] As shown in the figure, the two rectangles shown by the dotted lines below the wafer 2 represent two vacuum suction cups for adsorbing the wafer 2. The middle waist-shaped part does not contact the wafer 2. The vacuum suction cup 1 in the figure is shown as a dotted line, indicating that it is located below the wafer 2; the manipulator 4 in the figure is shown as a solid line, indicating that it is located above the wafer 2.

[0064] The manipulator 4 includes a first set of jaws 5 and a second set of jaws 6. Optionally, the first set of jaws may be fixed and the second set of jaws may be movable, or vice versa. The first set of jaws 5 includes a first jaw 7 and a second jaw 8, and the second set of jaws 6 includes a third jaw 9 and a fourth jaw 10. The first jaw 7 and the second jaw 8 are connected together at the proximal end, and the third jaw 9 and the fourth jaw 10 are connected together at the proximal end. Clamping wheels are respectively installed at the distal ends of the first jaw 7, the second jaw 8, the third jaw 9, and the fourth jaw 10 for clamping the wafer 2. The clamping wheels can be set to be rotatable respectively.

[0065] The first set of jaws 5 and the second set of jaws 6 can move relative to each other, so that the clamping wheels at the distal ends of the first jaw 7 and the second jaw 8 and the clamping wheels at the distal ends of the third jaw 9 and the fourth jaw 10 approach or move away from each other, thereby realizing the clamping and releasing of the wafer.

[0066] The relative movement of the first set of jaws 5 and the second set of jaws 6 can be achieved by a cylinder. For example, in one embodiment, one of the first set of jaws 5 and the second set of jaws 6 can be fixed on the arm (not shown) of the polishing manipulator. At the same time, a cylinder can be provided on the arm of the polishing manipulator. The cylinder block of the cylinder can be fixed to the arm of the polishing manipulator, and the piston rod is connected to the other of the first set of jaws 5 and the second set of jaws 6, thereby driving their relative movement. Here, the arm of the polishing manipulator is the frame relative to the first set of jaws 5 and the second set of jaws 6, and the relative movement between the two is defined by the cylinder. The cylinder can be replaced with an oil cylinder which is also a pressure cylinder.

[0067] Specifically, in one embodiment, a cylinder can be connected to the right end of the first set of jaws 5, and the cylinder pushes the first set of jaws 5 to move. The cylinder block of the cylinder can be fixedly connected to the right end of the second set of jaws 6. The first set of jaws 5 and the second set of jaws 6 form a wafer picking manipulator 4. The second set of jaws 6 is the fixed end, and the first set of jaws 5 is the movable end. In one embodiment, when clamping the wafer 2, the manipulator 4 is inserted under the wafer 2, passes between the two vacuum suction cups 1. After reaching the position, the first set of jaws 5 is pushed forward, and the second set of jaws 6 and the first set of jaws 5 clamp the wafer 2.

[0068] In this figure, it can be seen that the wafer 2 is adsorbed on the vacuum suction cup 1, and the wafer 2 is in a position completely covering the vacuum suction cup 1. At this position, the wafer 2 has been thinned at the grinding module 21 and cleaned at the cleaning device 43. The wafer 2 is not in a dry state, and there is a water film on the back of the wafer 2. The wafer 2 is transported from the grinding module 21 to the position to be picked up by the polishing manipulator 33 by the second transfer unit 27, and the polishing manipulator 33 transports it to the chemical mechanical polishing unit 29 of the polishing module 22 for polishing treatment.

[0069] In this figure, the first set of jaws 5 and the second set of jaws 6 of the manipulator 4 (which is the polishing manipulator 33 in this embodiment) have clamped the wafer 2 through the first jaw 7, the second jaw 8, the third jaw 9, and the fourth jaw 10, and are in a state ready to perform a handling operation. In this state, the operating modes that the manipulator 4 can adopt include, but are not limited to, vertically moving the wafer 2 away from the vacuum chuck 1 and laterally moving, vertically moving, swinging up and down, and concentrically rotating the wafer 2 relative to the vacuum chuck 1 in the illustrated orientation.

[0070] Here, it should be noted that although two vacuum chucks 1 are shown in the illustrated example and their shapes are square, in alternative embodiments, according to requirements, the vacuum chuck 1 can also have other shapes such as circular, other polygonal, irregular shapes, etc., and the number of vacuum chucks 1 can also be other numbers, and the arrangement can also be different from that shown in the figure.

[0071] Figure 3 is schematically shown Figure 2 the water film between the wafer 2 and the vacuum chuck 1 of the transfer assembly.

[0072] The figure shows the wafer 2, the vacuum chuck 1, and the water film 3 therebetween. Since the wafer 2 covers the entire vacuum chuck 1, the water film 3 is distributed on the surface of the entire vacuum chuck 1. At this point, the area of the water film 3 is equal to the area of the vacuum chuck 1. Below the vacuum chuck 1 in the figure, its adjacent components are also shown, which are used to connect it to the second transfer unit and will not be elaborated here.

[0073] The figure also schematically shows the third jaw 9 and the first jaw 7. It can be understood that according to the actual needs of wafer handling, in addition to Figure 2 and Figure 3 the clamping method shown, the manipulator 4 can also be clamped by a different number of jaws from that shown in the figure, such as but not limited to 3 jaws, 5 jaws, or other numbers of jaws.

[0074] Before the manipulator 4 transfers the wafer 2 from the vacuum chuck 1 of the second transfer unit 27, the wafer 2 is adsorbed by the vacuum chuck 1. Although they are in close contact, since the wafer is transferred to the vacuum chuck 1 without being dried after the cleaning process, a thin water film is still formed between the wafer and the vacuum chuck.

[0075] When the manipulator 4 starts the transfer operation, the wafer can first reach the position as in Figure 3 through the operation of each jaw by the manipulator 4. That is, as can be seen from the figure, when the manipulator 4 starts the transfer operation, the wafer 2 does not move along Figure 2It is shown in the figure that the wafer performs actions such as horizontal, vertical, swinging, and rotating. Instead, it only moves vertically away from the vacuum chuck 1, that is, it moves upward along the Z-axis by a predetermined distance, for example, from 200 μm to 400 μm, and more specifically, it can be 300 μm. When the wafer 2 is transported upward by the manipulator 4 and moves away from the vacuum chuck 1 by the illustrated distance, the water film between the two does not break, and the water film 3 still exists. However, through this upward movement, it is possible to avoid scratches on the wafer caused by the crystal slag remaining in the previous process when the wafer and the chuck move relatively in translation, swing, or rotation.

[0076] As can be seen from the figure, the wafer 2 is generally parallel to the vacuum chuck 1 and has moved upward by a certain distance from the position where it is attached to the vacuum chuck 1. Nevertheless, the water film 3 still remains between the wafer 2 and the vacuum chuck 1. Due to the water film tension, the thickness of the water film 3 has not reached the breaking point. In this case, it is possible to avoid the wafer 2 suddenly breaking the liquid tension and separating from the vacuum chuck 1, causing the water film 3 to suddenly break. Such a sudden break is likely to cause vibration and trembling at the end of the jaws of the wafer and the manipulator 4, resulting in damage to the contact part between the wafer and the jaws of the manipulator 4 and affecting the service life of the polishing manipulator.

[0077] Figure 4 The figure shows a top view schematic of the jaws of the polishing manipulator in the wafer processing apparatus, and at the same time shows the vacuum chuck 1 and the wafer 2 of the transfer assembly in the second positional relationship. Figure 5 Schematically shown Figure 4 the water film 3 between the wafer and the vacuum chuck 1 of the transfer assembly in the figure.

[0078] When the manipulator 4 holds the wafer to reach the distance between the wafer 2 and the vacuum chuck 1 as shown in Figure 3 the figure, the manipulator 4 does not further move the wafer 2 vertically away from the vacuum chuck 1, but translates the wafer 2 horizontally to the right in the figure until it gradually reaches the position as shown in Figure 4 the figure. This movement process can be parallel to the contact surface between the wafer and the vacuum chuck.

[0079] In Figure 4 the shown position, the wafer 2 only partially covers the two vacuum chucks 1. At the position where the wafer 2 and the vacuum chuck 1 overlap each other, the water film 3 still remains between them and the water film 3 does not break. The figure shows the distance H that the manipulator 4 moves upward away from the vacuum chuck 1. This is because when the wafer 2 is gradually transported and moved horizontally by the jaws of the manipulator 4, as the overlapping area between the wafer 2 and the vacuum chuck 1 gradually decreases, the area of the water film 3 between the two also gradually decreases.

[0080] In this process, due to the action of liquid tension, although the area of the water film 3 gradually decreases, it does not overcome the liquid tension of the water film and will not cause the water film 3 to rupture or break. However, as the area of the water film 3 decreases, the pulling force of the water film 3 between the wafer 2 and the vacuum chuck 1 gradually decreases, and the acting force of the water film 3 on the wafer 2 also gradually becomes smaller. Therefore, at the relative position shown in Figure 4 , even if the manipulator 4 continues to vertically move the wafer 2 away from the vacuum chuck 1, causing the water film 3 to break, it will not cause severe vibration and trembling at the end of the jaws of the wafer 2 and the manipulator 4, and thus can avoid damage to the contact part between the two. Compared with making the wafer 2 vertically separate from the vacuum chuck 1 at the position shown in Figure 2 , beneficial technical effects can be achieved.

[0081] During the process of reducing the area of the water film, the overlapping area or the area of the water film between the wafer 2 and the vacuum chuck 1 can be detected to see if it is less than a preset value. When it is less than the preset value, the process can proceed to the step of breaking the water film; when it is greater than or equal to the preset value, it returns to the step of reducing the area of the water film, that is, continues to reduce the water film until the overlapping area or the area of the water film is detected to be less than the preset value. This detection step can be carried out by visual inspection or a sensor.

[0082] In the present invention, the preset value is 1 / 10 or 1 / 5 of the wafer area to define the overlapping area between the wafer 2 and the vacuum chuck 1. It should be noted that the preset value can also be other values, such as 1 / 6 or 1 / 8 of the wafer area.

[0083] In another operation mode, after the manipulator 4 drives the wafer 2 to swing to the position shown in Figure 4 , the manipulator 4 can also continue to drive the wafer 2 to move horizontally until the water film 3 between the wafer 2 and the vacuum chuck 1 gradually becomes smaller and until it gradually completely disappears. This method also maximally overcomes the vibration damage of the wafer and the manipulator caused by the breakage of the water film. The subsequent horizontal movement of the wafer can also be horizontal, vertical, swinging, rotating, etc.

[0084] In this Figure 4 example, compared with the position shown in Figure 2 , the manipulator 4 has caused the wafer 2 to move horizontally in the transverse direction in Figure 4 relative to the vacuum chuck 1, achieving the effect of gradually reducing the area of the water film 3. In other embodiments, the wafer 2 can also be made to perform other horizontal movements relative to the vacuum chuck 1. For example, the wafer 2 can move horizontally in the vertical direction in Figure 4 relative to the vacuum chuck 1, the wafer 2 can swing or rotate horizontally relative to the vacuum chuck 1, etc. Through these horizontal movements, the effect of gradually reducing the area of the water film 3 can also be achieved, and the acting force of the water film 3 on the wafer 2 can be reduced. For example, Figure 6An example in which the manipulator 4 drives the wafer 2 to swing horizontally is shown.

[0085] In the present invention, swinging refers to the manipulator 4 driving the wafer 2 to swing, and rotation is to make the wafer 2 rotate around its own center. Swinging and translation can reduce the overlapping area between the wafer and the vacuum chuck, while rotation can stretch the liquid layer in the middle and reduce the liquid layer area, playing a role in reducing the water film tension to a certain extent. It can be understood that a driving module can be configured for the clamping wheel of the jaw to drive the clamping wheel to rotate around its own axis, and the frictional force between the clamping wheel and the edge of the wafer can drive the wafer 2 to rotate. That is, a driving module can be configured for the clamping wheels of the first jaw 7, the second jaw 8, the third jaw 9, and the fourth jaw 10 to achieve the rotation of the wafer 2.

[0086] Figure 6 A top view schematic diagram of the polishing manipulator jaw in the wafer processing apparatus is shown, and at the same time, the vacuum chuck 1 and the wafer 2 of the transfer assembly in the third positional relationship are shown.

[0087] When the manipulator 4 clamps the wafer 2 to reach the distance between the wafer 2 and the vacuum chuck 1 as shown in Figure 3 , the manipulator 4 does not further vertically move the wafer 2 away from the vacuum chuck 1, but horizontally swings the wafer 2 to gradually reach the position as shown in Figure 6 .

[0088] At Figure 6 The position shown, the wafer 2 only partially covers one vacuum chuck 1 in the figure. At the position where the wafer 2 and the vacuum chuck 1 overlap each other, a water film 3 still remains between them, and the water film 3 does not break. This is because when the wafer 2 is gradually swung horizontally by the jaws of the manipulator 4, as the overlapping area between the wafer 2 and the vacuum chuck 1 gradually decreases, the area of the water film 3 between them also gradually decreases.

[0089] In this process, although the area of the illustrated water film 3 gradually decreases, the liquid tension of the water film is not overcome, and the water film 3 will not break or rupture. At this time, as the area of the water film 3 decreases, the pulling force of the water film 3 between the wafer 2 and the vacuum chuck 1 gradually decreases, and the acting force of the water film 3 on the wafer 2 also gradually becomes smaller. Therefore, at the relative position shown in Figure 6 , even if the manipulator 4 vertically moves the wafer 2 away from the vacuum chuck 1 again, causing the water film 3 to break, it will not cause severe vibration and shaking of the wafer 2 and the manipulator 4, and thus can avoid damage to the contact part between the two. Compared with vertically separating the wafer 2 from the vacuum chuck 1 at the position shown in Figure 2 , beneficial technical effects can be produced.

[0090] In another operation mode, the manipulator 4 drives the wafer 2 to swing to Figure 6After reaching the position, the robot arm 4 can also continue to drive the wafer 2 to move horizontally until the water film 3 between the wafer 2 and the vacuum chuck 1 gradually becomes smaller and until it gradually disappears completely. This method also maximally overcomes the vibration and shaking damage of the wafer and the robot arm caused by the rupture of the water film.

[0091] In other embodiments, after reaching Figure 6 the shown position, the subsequent horizontal movement of the wafer can also be lateral, vertical, swinging, rotating, etc., so that the water film 3 gradually disappears.

[0092] Here, returning to combine Figure 1 the wafer processing device shown and the relevant descriptions in this specification, in an alternative embodiment of the present invention, Figures 2 to 6 the robot arm 4 in Figure 1 can be the polishing robot arm 33 of the wafer processing device in Figures 2 to 6 ; in other embodiments, Figure 1 the robot arm 4 in

[0093] Figure 7 can also be the robot arm in other modules of the wafer processing device in

[0094] such as, but not limited to, the grinding robot arm 42 in the grinding module 21. Figures 1 to 6 Combined with Figure 7 , it can be seen from the flowchart of

[0095] that the wafer picking method of the present invention is used to pick up the wafer 2 from the vacuum chuck 1, and the method includes the following steps I to III. Specifically, it includes: Step I, reducing the area of the water film 3 between the wafer 2 and the vacuum chuck 1; Step II, moving the wafer 2 away from the vacuum chuck 1 to break the water film; Step III, taking away the wafer 2.

[0096] Optionally, before step I, the robot arm 4 can be used to transport the wafer 2 so that the wafer 2 is vertically moved away from the vacuum chuck 1 by a certain distance. According to specific circumstances, the distance can be 200 μm to 400 μm; more specifically, in a further alternative embodiment, the distance can also be 300 μm. By first moving the wafer vertically away from the vacuum chuck by a certain distance and then performing horizontal transportation before horizontal transportation of the wafer, it is possible to avoid scratching the wafer by particles such as debris and crystal slag between the wafer and the vacuum chuck. It can be understood that in the cleaning process before wafer picking, there may be debris, crystal slag, etc. that are not washed away, which affect wafer transportation. The operation of this step avoids such adverse situations.

[0097] In a specific embodiment, the area of the water film 3 can be reduced by horizontally transporting the wafer 2 using a manipulator 4. Specifically, it is transported parallel to the contact surface between the wafer 2 and the vacuum chuck 1. By horizontally transporting the wafer 2 using the manipulator 4, the wafer 2 can be horizontally moved, rotated, or swung relative to the vacuum chuck 1, gradually changing the positional relationship between the wafer and the vacuum chuck, reducing the overlapping area between the wafer 2 and the vacuum chuck 1, and gradually reducing the area of the water film, thereby reducing the liquid tensile force of the water film between the wafer and the chuck. After this process, after the liquid tensile force is reduced to a certain extent, disconnecting the water film will not cause severe vibration and trembling of the wafer and the manipulator, and can protect the wafer and the manipulator from damage.

[0098] As described above, if the wafer 2 is vertically lifted away from the vacuum chuck 1 by a certain distance and then the wafer 2 is horizontally moved, rotated, or swung using the manipulator 4 in step I, it is possible to avoid scratching of the wafer caused by debris, crystal slag, etc.

[0099] In addition, in some embodiments, in order to more stably reduce the water film, in step I, a certain amount of gas can also be distributed to the wafer 2 via the vacuum chuck 1 to break the vacuum between the vacuum chuck 1 and the wafer 2. In this case, optionally, the vacuum chuck 1 can be made of a porous ceramic material, and gas distribution is carried out by the porous ceramic material. A gas channel can be provided below the vacuum chuck, and its communication with the wafer surface is realized through the porous ceramic to achieve the entry and exit of gas or other fluids and adjust the properties of the water film. When clean gas is distributed between the wafer and the vacuum chuck, the gas can accelerate the evaporation of moisture to assist in reducing the area of the water film; when clean gas is distributed to the water film, according to the distribution amount and distribution speed of the gas, the liquid tension can also be appropriately decomposed, which is beneficial to the uniform and gradual reduction of the water film area and will not cause severe vibration and trembling.

[0100] In step II, the wafer 2 is moved away from the vacuum chuck 1 to disconnect the water film.

[0101] In this step, the manipulator 4 can be used to transport the wafer 2 so that the wafer 2 is vertically lifted away from the vacuum chuck 1 to break the tension and pull open the water film. Alternatively, in an alternative embodiment, the manipulator 4 can be used to transport the wafer 2 so that the wafer 2 continues to be horizontally moved, rotated, or swung relative to the vacuum chuck 1, gradually moving away from the vacuum chuck, and finally breaking the tension and pulling open the water film.

[0102] Since the liquid tensile force has been reduced in the previous Step I by means such as reducing the water film area and / or distributing gas through the vacuum chuck, breaking the water film in this Step II will not cause severe vibration and tremor of the wafer and the manipulator, thus avoiding damage caused thereby. Optionally, during the process of breaking the water film, gas can also be distributed to the wafer 2 via the vacuum chuck 1, which can help reduce the undesired component vibration.

[0103] During the process of the said Step I, it is also possible to detect whether the overlapping area or the water film area between the wafer 2 and the vacuum chuck 1 is less than a preset value: when it is less than the preset value, proceed to Step II of breaking the water film; when it is greater than or equal to the preset value, return to Step I of reducing the water film, that is, continue to reduce the water film. This detection can be achieved by visual inspection or a sensor.

[0104] In Step III, the wafer 2 is taken away. After the water film between the wafer and the vacuum chuck is broken, the manipulator can remove the wafer 2 by an appropriate motion mode and transport it to the next process.

[0105] The present invention further provides a wafer transfer method applied to a wafer processing apparatus 20. The wafer transfer method may include the step of using a manipulator 4 to pick up the wafer 2 from the vacuum chuck 1, wherein the manipulator 4 picks up the wafer 2 from the vacuum chuck 1 by the method described in any one of the foregoing embodiments. The wafer processing apparatus 20 may include a grinding module 21, a polishing module 22, and a transfer assembly between the grinding module 21 and the polishing module 22, such as the second transfer unit 27 in Figure 1 The transfer assembly includes a vacuum chuck 1, the manipulator 4 may be a polishing manipulator 33 at the polishing module 22, and the polishing manipulator 33 is used to transport the wafer 2 from the transfer assembly to the polishing module 22. In other alternative embodiments, the manipulator 4 may be a manipulator in other transfer assemblies or transfer units of the wafer processing apparatus 20.

[0106] The present invention further provides a wafer processing method including the foregoing wafer transfer method, which may specifically include:

[0107] Grinding the wafer by using the grinding module 21 of the wafer processing apparatus 20;

[0108] Transferring the ground wafer to the polishing module of the wafer processing apparatus by using this wafer transfer method;

[0109] Polishing the wafer by using the polishing module 22.

[0110] The present invention further provides a computer storage medium, on which a computer program is stored. When the program is executed by a processor, the foregoing wafer picking method can be implemented. Specifically, a system or device equipped with a storage medium can be provided. On this storage medium, software program codes for implementing the functions of any one of the foregoing embodiments are stored, and the computer (or CPU or MPU) of the system or device is caused to read and execute the program codes stored in the storage medium. In this case, the program codes read from the storage medium itself can implement the functions of any one of the foregoing embodiments. Therefore, the program codes and the storage medium storing the program codes constitute a part of the present application. Embodiments of the storage medium for providing program codes include floppy disks, hard disks, magneto-optical disks, optical disks (such as CD-ROM, CD-R, CD-RW, DVD-ROM, DVD-RAM, DVD-RW, DVD+RW), magnetic tapes, non-volatile memory cards, and ROMs. Optionally, the program codes can be downloaded from a server computer via a communication network.

[0111] The present invention further provides a wafer transfer device. The wafer transfer device may include a vacuum chuck 1 and a transfer mechanism. For example, the transfer mechanism may include the foregoing manipulator for clamping the wafer. The vacuum chuck is configured to receive the wafer. The transfer mechanism is configured to pick up the wafer from the vacuum chuck by the method described in any one of the foregoing embodiments. Optionally, the wafer transfer device may further include a controller connected to the transfer mechanism. An execution program may be built into the controller, and the controller is configured to be able to run the execution program to control the transfer mechanism to execute the wafer picking method.

[0112] The present invention further provides a wafer processing device 20. The wafer processing device 20 may include a grinding module 21, a polishing module 22, and a transfer component between the grinding module 21 and the polishing module 22. During the process of the wafer 2 being thinned in the grinding module 21 and then being returned, a cleaning operation is performed on the back of the wafer, and a water film adheres to the surface of the wafer after cleaning. The transfer component includes the vacuum chuck 1, and the manipulator 4 is the polishing manipulator of the polishing module 22. The polishing manipulator is used to transport the wafer 2 from the transfer component to the polishing module 22. Moreover, the polishing manipulator picks up the wafer 2 from the vacuum chuck 1 by the method described in any one of the foregoing embodiments to avoid damage to the wafer and / or the manipulator caused by vibration and trembling due to the destruction of the liquid tension between the wafer and the vacuum chuck.

[0113] Specifically, the thinning process of the wafer 2 in the thinning station of the wafer processing apparatus 20 can be as follows: The wafer 2 is transported by the transfer assembly to the grinding module 21. After the thinning in the grinding module 21 is completed, it is picked up by the manipulator 4 via the transfer assembly and transferred to the polishing module 22. The transfer assembly has a vacuum chuck 1 for adsorbing the wafer 2, and the manipulator 4 can have jaws for clamping and transporting the wafer 2. The manipulator 4 in this example can be the polishing manipulator 33.

[0114] The technical scope of the present invention is not limited to the content in the above specification. Those skilled in the art can make various deformations and modifications to the above embodiments without departing from the technical idea of the present invention, and these deformations and modifications should all fall within the scope of the present invention.

Claims

1. A wafer picking method, characterized in that, The method uses the jaws of a manipulator (4) to pick up a wafer (2) from a vacuum chuck (1). The method comprises the following steps: Step I: Move the wafer (2) parallel to the contact surface between the wafer (2) and the vacuum chuck (1) using the manipulator (4) to reduce the area of the water film (3) between the wafer (2) and the vacuum chuck (1). Step II: Move the wafer (2) away from the vacuum chuck (1) to break the water film. Step III: Remove the wafer (2). In Step I, moving the wafer (2) parallel to the contact surface between the wafer (2) and the vacuum chuck (1) includes: translating or swinging the wafer (2) parallel to the contact surface between the wafer (2) and the vacuum chuck (1). The method further includes: before Step I, using the manipulator (4) to transport the wafer (2) so that the wafer (2) is vertically moved away from the vacuum chuck (1) by a distance of 200 μm to 400 μm, within which distance the water film is not broken; in Step I, distributing gas to the wafer (2) via the vacuum chuck (1), the gas causing the water to evaporate to assist in reducing the area of the water film, and decomposing the liquid tension and uniformly and gradually reducing the area of the water film according to the distribution amount and distribution speed of the gas.

2. The method according to claim 1, wherein During Step I, detect whether the overlapping area or the area of the water film between the wafer (2) and the vacuum chuck (1) is less than a preset value: when it is less than the preset value, proceed to Step II; when it is greater than or equal to the preset value, return to Step I.

3. The method according to claim 1, characterized in that, The distance is 300 μm.

4. The method according to claim 1, wherein In Step I, moving the wafer (2) parallel to the contact surface between the wafer (2) and the vacuum chuck (1) includes: rotating the wafer (2) during the process of translating or swinging the wafer (2) parallel to the contact surface between the wafer (2) and the vacuum chuck (1).

5. The method according to claim 1, wherein The vacuum chuck (1) is made of a porous ceramic material, and gas is distributed by the porous ceramic material.

6. The method according to claim 1, characterized in that, In Step II, translate, rotate or swing the wafer parallel to the contact surface between the wafer (2) and the vacuum chuck (1) to move the wafer (2) away from the vacuum chuck and break the water film.

7. The method according to claim 1, wherein The manipulator (4) includes a first set of jaws (5) and a second set of jaws (6). The first set of jaws (5) includes a first jaw (7) and a second jaw (8) arranged side by side. The second set of jaws (6) includes a third jaw (9) and a fourth jaw (10) arranged side by side. The first set of jaws (5) and the second set of jaws (6) can move relative to each other to pick up and transport the wafer (2).

8. The method according to claim 7, wherein The second set of jaws (6) is controlled by a pressure cylinder, and the pressure cylinder is an oil cylinder or a pneumatic cylinder.

9. A wafer transfer method applied to a wafer processing apparatus, characterized in that, The wafer transfer method includes the step of using a manipulator (4) to pick up a wafer (2) from a vacuum chuck (1), wherein the manipulator (4) picks up the wafer (2) from the vacuum chuck (1) by the method described in any one of the preceding claims 1 to 8.

10. The method according to claim 9, wherein The wafer processing apparatus (20) includes a grinding module (21), a polishing module (22), and a transfer assembly between the grinding module (21) and the polishing module (22). The transfer assembly includes the vacuum chuck (1). The manipulator (4) is a polishing manipulator of the polishing module (22), and the polishing manipulator is configured to transfer the wafer (2) from the transfer assembly to the polishing module (22).

11. A wafer processing method, characterized in that, Comprising: Grinding a wafer using the grinding module (21) of the wafer processing apparatus (20); Transferring the ground wafer to the polishing module (22) of the wafer processing apparatus (20) using the wafer transfer method according to claim 9 or 10; Polishing the wafer using the polishing module (22).

12. A wafer transfer device, characterized in that, The wafer transfer apparatus includes: A vacuum chuck configured to receive a wafer; A transfer mechanism configured to pick up the wafer from the vacuum chuck by the method according to any one of the preceding claims 1 to 8.

13. The wafer transfer device according to claim 12, wherein, The wafer transfer apparatus further includes a controller connected to the transfer mechanism. An execution program is built in the controller, and the controller is configured to run the execution program to control the transfer mechanism to execute the method.

14. A wafer processing apparatus, characterized in that, The wafer processing apparatus (20) includes a grinding module (21), a polishing module (22), and a transfer assembly between the grinding module (21) and the polishing module (22). The transfer assembly includes the vacuum chuck (1). The polishing module (22) includes a polishing manipulator configured to transfer the wafer (2) from the transfer assembly to the polishing module (22), and the polishing manipulator picks up the wafer (2) from the vacuum chuck (1) by the method according to any one of the preceding claims 1 to 8.

15. A computer storage medium having a computer program stored thereon, which when executed by a processor implements the method according to any one of claims 1 - 8.

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