Wafer chuck device and wafer clamping state detection method

Abstract

The invention provides a wafer chuck device and a wafer clamping state detection method. In the wafer chuck device, a first rotating part and a base are coaxial, and a driving motor is used for driving the base and the first rotating part to rotate relatively; the first end of the elastic piece is fixedly connected with the base, the second end of the elastic piece is fixedly connected with the first rotating piece, and when the base and the first rotating piece rotate relatively, the elastic piece generates stress to enable the driving motor to generate torque change; the second rotating part is arranged on the base, the clamping part is arranged on the second rotating part, the second rotating part is in transmission connection with the first rotating part, and when the base and the first rotating part rotate relatively, the second rotating part rotates and drives the clamping part to rotate among an opening position, a clamping position and a closing position. The clamping position represents the position of the clamping piece when the wafer is clamped; wherein the wafer chuck device is configured to output the relationship between the rotation angle and the torque of the driving motor in the process of loading and / or unloading the wafer.

Description

Technical Field

[0001] The present application mainly relates to the field of semiconductor manufacturing, and in particular to a wafer chuck device and a method for detecting a wafer clamping state. Background Art

[0002] In the wafer processing chamber, a wafer clamping device (or chuck) is generally used to clamp the wafer and drive the wafer to rotate for various processes. If the clamping device does not clamp the wafer properly and starts to operate, it will cause damage to the wafer. In order to detect the clamping state of the wafer, one or more sets of sensors can be set in the wafer processing chamber to detect whether the wafer is clamped properly. If the wafer is not clamped properly, the machine will be shut down to avoid wafer damage.

[0003] Patent CN115458471A proposes a chuck device and a method for detecting the state of a wafer. The patent sets a position detection component in the chuck device to detect the relative position parameters between the chuck base and the drive disk, and uses the relative position parameters to determine whether the chuck device clamps the wafer. However, in addition to increasing costs, setting up sensors will also reduce the maintainable space in the cavity. In addition, in wafer liquid processing cavities, such as cleaning machines, the splash protection design of the sensor must be considered, which brings difficulties to the design. In addition, in high-process cavities with high requirements for cavity sealing, holes must be opened in the cavity to meet the lead-out of the sensor circuit, which brings difficulties to the sealing design. Summary of the invention

[0004] The present application provides a wafer chuck device that directly obtains the wafer clamping state according to the relationship between the rotation angle and torque of a driving motor of the chuck device, so as to solve the problem that the wafer clamping state is difficult to detect.

[0005] To solve the above technical problems, one aspect of the present application provides a wafer chuck device, comprising: a base, a driving motor, a first rotating member, a second rotating member, a clamping member and an elastic member, wherein the first rotating member is coaxial with the base, and the driving motor is used to drive the base and the first rotating member to rotate relative to each other; the elastic member has a first end and a second end, the first end is fixedly connected to the base, and the second end is fixedly connected to the first rotating member, when the base and the first rotating member rotate relative to each other, the elastic member generates stress to make the driving motor generate torque changes; the second rotating member is arranged on the base, the clamping member is arranged on the second rotating member, the second rotating member is transmission-connected with the first rotating member, when the base and the first rotating member rotate relative to each other, the second rotating member rotates by itself, and drives the clamping member to rotate between an open position, a clamping position and a closed position, wherein the clamping position indicates the position of the clamping member when the wafer is clamped; wherein the wafer chuck device is configured to: output the relationship between the rotation angle and torque of the driving motor during loading and / or unloading of wafers.

[0006] Another aspect of the present application provides a method for detecting the wafer clamping state, comprising: obtaining the relationship between the rotation angle and torque of the drive motor during the process of loading and / or unloading the wafer; and judging whether the wafer clamping is normal based on the relationship.

[0007] The wafer chuck device and monitoring method of the present application utilize the relationship between the rotation angle and torque that can be obtained by the driving motor of the wafer chuck device itself during the process of loading and unloading wafers, and judge whether the wafer clamping is normal or abnormal based on the corresponding rotation angle when the torque suddenly changes. It does not require the aid of additional sensor devices, sealing devices, etc., and has the advantages of simple structure and low cost, and is suitable for any type of wafer processing chamber. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The accompanying drawings are included to provide a further understanding of the present application. They are included and constitute a part of the present application. The accompanying drawings illustrate embodiments of the present application and together with the present specification serve to explain the principles of the present application. In the accompanying drawings:

[0009] Figure 1 and Figure 2 It is a schematic diagram of the three-dimensional structure of a wafer chuck device according to an embodiment of the present application;

[0010] Figure 3 and Figure 4 yes Figure 1 A front cross-sectional view of the wafer chuck apparatus of the illustrated embodiment;

[0011] Figure 5 This is a schematic diagram of a wafer chuck device according to an embodiment of the present application when the wafer is normally clamped;

[0012] Figure 6 yes Figure 5 A magnified schematic diagram of the middle area A;

[0013] Figure 7 is a top view of a wafer chuck device according to another embodiment of the present application;

[0014] Figure 8 is a top view of a wafer chuck device according to another embodiment of the present application;

[0015] Fig. 9 is a schematic diagram of a wafer chuck device according to an embodiment of the present application when the wafer is not clamped;

[0016] Fig.10 yes Fig. 9 A magnified schematic diagram of the middle area B;

[0017] Fig.11 is a diagram showing the relationship between the rotation angle of the drive motor and the torque during wafer unloading when the wafer is clamped normally;

[0018] Fig.12 is a diagram showing the relationship between the rotation angle and torque of the driving motor during unloading of the wafer when the wafer is abnormally clamped;

[0019] Fig.13 It is a schematic diagram of the relationship between the rotation angle of the drive motor and the torque during the wafer loading process when the wafer is clamped normally;

[0020] Fig.14 is a diagram showing the relationship between the rotation angle of the drive motor and the torque during wafer loading when the wafer is abnormally clamped;

[0021] Figure 15A-Figure 15C A schematic diagram showing the process of unloading a wafer when the wafer is clamped normally;

[0022] Figure 16A-16C Schematic diagram showing the process of unloading a wafer when the wafer is abnormally clamped. DETAILED DESCRIPTION

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for the description of the embodiments. Obviously, the drawings described below are only some examples or embodiments of the present application. For ordinary technicians in this field, the present application can also be applied to other similar scenarios based on these drawings without creative work. Unless it is obvious from the language environment or otherwise explained, the same reference numerals in the figures represent the same structure or operation.

[0024] As shown in this application, unless the context clearly indicates an exception, the words "a", "an", "a kind" and / or "the" do not refer to the singular, but also include the plural. Generally speaking, the terms "include" and "comprise" only indicate the inclusion of the steps and elements that have been clearly identified, and these steps and elements do not constitute an exclusive list, and the method or device may also include other steps or elements.

[0025] Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values ​​of the parts and steps set forth in these embodiments do not limit the scope of the present application. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to those of ordinary skill in the relevant field may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be considered as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so that once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0026] In the description of the present application, it should be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction, and therefore cannot be understood as limiting the scope of protection of the present application; the directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0027] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0028] In addition, it should be noted that the use of words such as "first" and "second" to define components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above words have no special meaning and cannot be understood as limiting the scope of protection of this application. In addition, although the terms used in this application are selected from well-known and commonly used terms, some terms mentioned in the specification of this application may be selected by the applicant at his or her discretion, and their detailed meanings are explained in the relevant parts of the description of this article. In addition, it is required to understand this application not only by the actual terms used, but also by the meaning implied by each term.

[0029] Flowcharts are used in the present application to illustrate the operations performed by the system according to the embodiments of the present application. It should be understood that the preceding or following operations are not necessarily performed accurately in order. On the contrary, various steps may be processed in reverse order or simultaneously. At the same time, other operations may be added to these processes, or one or more operations may be removed from these processes.

[0030] The wafer chuck device of the present application can be applied to various wafer processing chambers, including but not limited to dry process chambers, wet process chambers, etc. In addition to being applicable to various applicable processes of the wafer, the wafer chuck device of the present application is also suitable for detecting the clamping state of the wafer when necessary, without the need to add additional sensor devices.

[0031] Figure 1 and Figure 2 It is a schematic diagram of the three-dimensional structure of a wafer chuck device according to an embodiment of the present application, and the two have different viewing angles. Figure 3 and Figure 4 yes Figure 1 A front cross-sectional view of the wafer chuck assembly of the illustrated embodiment.

[0032] Figure 5 yes Figure 1 A top perspective view of the wafer chuck assembly in FIG. Figure 1 to Figure 5 As shown, the wafer chuck device 100 of this embodiment includes a base 110, a drive motor 101, a first rotating member 120, an elastic member 130, a second rotating member 140 and a clamping member 150. The drive motor 101 is used to drive the base 110 and / or the first rotating member 120 to rotate, so as to drive the wafer W to perform various process steps. The present application does not limit the driving principle of the drive motor 101.

[0033] In some embodiments, Figure 1 and Figure 2The wafer chuck device 100 further includes a rotating shaft 210 disposed below the base 110. The drive motor 101 is used to drive the rotating shaft 210 to rotate, thereby driving the base 110 and / or the first rotating member 120 to rotate. The drive motor 101 can be installed in the rotating shaft 210, or can be externally connected to the wafer chuck device 100 and connected to the rotating shaft 210 to control the rotation of the rotating shaft 210.

[0034] In some embodiments, Figure 3 As shown, the base 110 includes an upper base 111 and a lower base 112 that are integrated, and a hollow structure 113 located between the upper base 111 and the lower base 112, and the first rotating member 120 and the second rotating member 140 are both arranged in the hollow structure 113. The middle of the lower base 112 has an upwardly protruding central axis 114, and the first rotating member 120 is sleeved on the outer ring of the central axis 114. When the driving motor 101 drives the base 110 to rotate, the upper base 111 and the lower base 112 rotate simultaneously. In some embodiments, the driving motor 101 can simultaneously drive the first rotating member 120 and the base 110 to rotate synchronously.

[0035] In the wafer chuck device 100 of the present application, the drive motor 101 can drive the base 110 and the first rotating member 120 to rotate relative to each other, for example: the base 110 is kept stationary, and the drive motor 101 drives the first rotating member 120 to rotate; the first rotating member 120 is kept stationary, and the drive motor 101 drives the base 110 to rotate; the drive motor 101 drives the base 110 to rotate in a first direction, and drives the base 110 to rotate in a second direction at the same time, and the first direction and the second direction are opposite. The present application is described by taking the drive motor 101 driving the base 110 to rotate as an example.

[0036] Combination Figure 1 and Figure 5 , the first rotating member 120 can be specifically implemented as a large gear, whose outer ring has gear teeth. The large gear is coaxial with the base 110, and the diameter of the large gear is slightly smaller than the diameter of the base 110. The second rotating member 140 is disposed on the base 110, for example, it can be fixedly connected to the lower base 112. At the same time, the second rotating member 140 can rotate around its own rotation axis. The diameter of the second rotating member 140 is smaller than the distance between the outer periphery of the large gear and the outer periphery of the base 110. Figure 5 As shown, the second rotating member 140 can be specifically implemented as a small gear, whose outer ring also has gear teeth, and the gear teeth of the large gear match the gear teeth of the small gear. Therefore, when the base 110 and the first rotating member 120 rotate relative to each other, the second rotating member 140 will be driven to rotate. It should be noted that although Figure 5 As shown, the outer ring of the large gear has gear teeth. In other embodiments, only the portion of the outer ring of the large gear that cooperates with the second rotating member 140 may have gear teeth, and the remaining portion may not have gear teeth.

[0037] like Figure 5 As shown, the plurality of second rotating members 140 are evenly spaced and arranged on the circumference of the first rotating member 120, and each second rotating member 140 is provided with a clamping member 150. In other embodiments, the plurality of second rotating members 140 may also be unevenly arranged.

[0038] In some embodiments, Figure 1 As shown, the clamping member 150 specifically includes a clamping column 151 and an eccentric cylinder 152. The clamping column 151 is coaxial with the second rotating member 140, and the eccentric cylinder 152 is eccentrically arranged on the upper surface of the clamping column 151. When clamping the wafer W, the wafer W is placed on the upper surface of the clamping column 151 and supported by the upper surface of the clamping column 151. At the same time, when the second rotating member 140 rotates, the eccentric cylinder 152 can rotate toward or away from the center of the wafer W, thereby changing the diameter of the circle surrounded by multiple eccentric cylinders 152. The rotation of the eccentric cylinder 152 away from the center of the wafer W is recorded as opening the clamping member, and the rotation of the eccentric cylinder 152 toward the center of the wafer W is recorded as closing the clamping member. It can be understood that when unloading the wafer W, the clamping member 150 needs to be opened first to release the wafer W; when loading the wafer W, the clamping member 150 also needs to be opened first, and after the wafer W is placed on the upper surface of the clamping column 151, the clamping member 150 is closed, and the rotation angle of the second rotating member 140 is adjusted according to the size of the wafer W, so that the multiple eccentric cylinders 152 clamp the wafer W together. The clamping member 150 has the functions of supporting, clamping the wafer W and limiting the position of the wafer W at the same time. When opened, the multiple clamping members 150 are in the open position, at which time the diameter of the enclosed circle is larger, and the wafer chuck device 100 is in the open state; when clamping the wafer normally, the multiple clamping members 150 are in the clamping position, at which time the diameter of the enclosed circle is smaller than the diameter in the open position, and the wafer chuck device 100 is in the clamping state; in the idle state without clamping the wafer, the multiple clamping members 150 can be in the closed position, at which time the diameter of the enclosed circle is smaller than the diameter in the clamping position, and the wafer chuck device 100 is in the closed state.

[0039] Figure 7 and Figure 8 2 are top views of wafer chuck devices of two other embodiments, which are used to illustrate the other two first rotating members and the second rotating members. Figure 7As shown, the first rotating member 710 is a snowflake-shaped member, wherein the middle portion 711 is sleeved on the outer periphery of the central axis 114, and a plurality of supporting rods 712 are radially arranged outward from the middle portion 711, and the end of each supporting rod 712 is movably connected to the second rotating member 720 through a connecting rod 730. In some embodiments, a multi-section connecting rod 730 can be used to movably connect the supporting rod 712 and the second rotating member 720. When the first rotating member 710 and the base 110 rotate relative to each other, the first rotating member 710 pushes the second rotating member 720 to rotate by the connecting rod 730, so that the clamping member 150 located on the second rotating member 720 rotates between the open position, the clamping position and the closed position.

[0040] like Figure 8 As shown, the first rotating member 810 is also snowflake-shaped, wherein the middle portion 811 is sleeved on the outer periphery of the central axis 114, and a plurality of supporting rods 812 are radially arranged outward from the middle portion 811, and the end 813 of each supporting rod 812 abuts against the second rotating member 820. The second rotating member 820 is a cam having two protrusions 831, 832, and the end 813 of the supporting rod 812 abuts against the portion between the two protrusions 831, 832. When the first rotating member 810 and the base 110 rotate relative to each other, the end 813 of the first rotating member 810 pushes the second rotating member 820 to rotate within a certain range, and the rotation causes the clamping member 150 located on the second rotating member 820 to rotate between an open position, a clamping position, and a closed position.

[0041] Figure 7 and Figure 8 Other structures in the embodiment shown are Figure 5 The structures of the embodiments shown are similar, and reference may be made to Figure 5 Description text to illustrate.

[0042] like Figure 5As shown, the elastic member 130 has a first end 131 and a second end 132, the first end 131 is fixedly connected to the base 110, and the second end 132 is fixedly connected to the first rotating member 120. In this embodiment, the elastic member 130 is specifically implemented as a spring. When the first rotating member 120 and the base 110 rotate synchronously, the elastic member 130 is in a preset tensile state, and the preset tensile state is different when there is a wafer and when there is no wafer. More specifically, the first rotating member 120 also includes a plurality of spokes 510 extending radially. Specifically, the first rotating member 120 includes an inner ring 501 and an outer ring 502, which are connected by the spokes 510. The first end 131 of the elastic member 130 can be set at any position on the base 110, for example, on the lower surface of the upper base 111, the upper surface of the lower base 112, etc. In this way, when the base 110 rotates, the first end 131 will be driven to move. The second end 132 of the elastic member 130 is specifically disposed on the spoke 510. When the first rotating member 120 rotates, the second end 132 is also driven to move. Figure 5 The figure is only an example. In other embodiments, the first rotating member 120 does not include spokes but other frame structures, and the second end 132 of the elastic member 130 can be set at any position on the frame structure. When the base 110 or the first rotating member 120 is driven to rotate, since the base 110 and the first rotating member 120 are connected by the elastic member 130 and have a linkage relationship, when the stress meets certain conditions, the base 110 and the first rotating member 120 rotate together, and a certain relative position relationship is maintained between the two. At this time, the length of the elastic member 130 is maintained at a certain length, and the torque output by the driving motor 101 is a smaller torque. The inventor of the present application found that when the base 110 and the first rotating member 120 rotate relative to each other, the elastic member 130 generates a large stress, which causes the torque of the drive motor 101 to change suddenly. The rotation angle corresponding to the sudden change is different when the wafer is clamped normally and when the wafer is clamped abnormally. Therefore, the wafer chuck device 100 of the present application is configured to output the relationship between the rotation angle and torque of the drive motor 101 during the process of loading and / or unloading the wafer. In this way, it can be judged whether the wafer clamping is normal or abnormal based on this relationship. Among them, the rotation angle and corresponding torque of the drive motor 101 are parameters that can be obtained by the drive motor 101 itself, and can be selectively output. According to the working principle of the drive motor 101, its rotation angle can be obtained according to the encoder, and its torque can be obtained according to the current.

[0043] The wafer chuck device 100 of the present application has a simple structure and does not require the installation of additional, specific sensors. By outputting the relationship between the rotation angle and torque of the drive motor 101, it can be used to judge whether the wafer clamping is normal or abnormal during the process of loading and unloading wafers. It has the advantages of low cost, high feasibility and strong practicality.

[0044] Further, in some embodiments, the wafer chuck device 100 is configured to determine whether the wafer clamping is normal based on the relationship between the rotation angle and torque of the drive motor 101, wherein the corresponding rotation angle when the torque of the drive motor 101 changes suddenly is different when the wafer clamping is normal and when the wafer clamping is abnormal. A sudden change in torque means that the torque suddenly increases or decreases, which can be used to determine the magnitude of the rate of change of the torque with the rotation angle. For example, the rate of change of the torque is set to reach a threshold value, and the torque is judged to have a sudden change, and the threshold value can be a positive number or a negative number.

[0045] Furthermore, the inventors of the present application have found in practice that the relationship between the rotation angle and the torque has different rules when unloading the wafer, loading the wafer, and when the wafer is clamped normally or abnormally, thereby obtaining different configuration modes of the wafer chuck device 100. One mode is: in the process of unloading the wafer, the clamping member 150 is switched to the open position, during which the rate of change of the torque is obtained. When the rate of change reaches a first preset value, it is determined that the torque of the drive motor 101 has a sudden change and the corresponding rotation angle is recorded as the unloading angle. When the unloading angle is within the first angle range, it indicates that the wafer is clamped normally, and when the unloading angle is not within the first angle range, it indicates that the wafer is clamped abnormally. Furthermore, a second angle range can also be set. When the unloading angle is within the second angle range, it indicates that the wafer is clamped abnormally, wherein the first angle range is greater than the second angle range, that is, the angles within the first angle range are all greater than the angles within the second angle range.

[0046] Another way is: in the process of loading the wafer, the clamping member 150 performs the wafer clamping action from the open position. In this process, the rate of change of the torque is obtained. When the rate of change reaches a second preset value, it is determined that the torque of the drive motor 101 has a sudden change and the corresponding rotation angle is recorded as the loading angle. When the loading angle is within the third angle range, it indicates that the wafer clamping is normal. When the loading angle is not within the third angle range, it indicates that the wafer clamping is abnormal. Further, a fourth angle range can be set. When the loading angle is within the fourth angle range, it indicates that the wafer clamping is abnormal, wherein the third angle range is smaller than the fourth angle range, that is, the angles within the third angle range are all smaller than the angles within the fourth angle range.

[0047] The first angle range, the second angle range, the third angle range, and the fourth angle range can be set by setting the first limiting member and the second limiting member and the positional relationship between the first limiting member and the first rotating member 120 .

[0048] Combination Figure 5 and Figure 6As shown, in this embodiment, the wafer chuck device 100 further includes a first stopper 160 for preventing the first rotating member 120 or the base 110 from rotating, so that the first rotating member 120 and the base 110 change from synchronous rotation to relative rotation. Figure 1 and Figure 2 As shown, in some embodiments, the wafer chuck device 100 includes a fixed seat 220, which is independently arranged from the rotating shaft 210. During the process, the position of the fixed seat 220 remains unchanged. Further, a cylinder 230 is arranged on the fixed seat 220, and the first limiter 160 is a limiter column arranged on the cylinder 230. The cylinder 230 is used to control the first limiter 160 to extend and retract in the vertical direction. Figure 2 Two cylinders 230 and two first stoppers 160 are shown, and the two first stoppers 160 are respectively located on both sides of the rotating shaft 210 and are symmetrically distributed. Figure 2 The figure is only an example, and the present application does not limit the number and position of the first limiter 160. The present application does not limit how the first limiter 160 is extended and retracted, and other methods other than the cylinder can be used to control the position of the first limiter 160. It can be understood that when there are multiple first limiters 160, the multiple first limiters 160 extend and retract together to jointly play a role in preventing the first rotating member 120 or the base 110 from rotating. The following is an example of the first limiter 160 preventing the first rotating member 120 from rotating.

[0049] like Figure 3 As shown, the first stopper 160 is in a retracted state, and its end does not extend into the base 110. At this time, the first stopper 160 cannot play its limiting role. When performing the wafer processing process, the wafer chuck device 100 drives the wafer W to rotate, and at this time the first stopper 160 is in a retracted state. Figure 4 As shown, the first stopper 160 is in an extended state, and its end extends into the base 110, which can prevent the first rotating member 120 or the base 110 from rotating. Figure 4 and Figure 5 The lower base 112 has a limiting hole 410. At the same time, there is a hollow structure 420 between the multiple spokes 510 of the first rotating member 120. The first limiting member 160 extends into the hollow structure 420. When the height of the first limiting member 160 is appropriate, it can contact the spoke 510, thereby blocking the rotation of the first rotating member 120.

[0050] Understandably, Figure 5The above is only an example. In other embodiments, the first stopper 160 can also be implemented in other embodiments. For example, the first rotating member 120 does not include the spokes 510, but includes some other structures, such as any frame structure, and a stopper is set at any position of the first rotating member 120 as a stopper. During the wafer processing, the stopper does not affect the normal rotation of the first rotating member 120. When the wafer needs to be loaded or unloaded, the first stopper 160 is extended and contacts the stopper, thereby preventing the first rotating member 120 from rotating.

[0051] like Figure 5 As shown, the embodiment also includes a second limiting member 170, which is disposed on the base 110 and is used to limit the relative position between the first rotating member 120 and the base 110. For example, the second limiting member 170 is a limiting column disposed on the lower surface of the upper base 111, or a limiting column disposed on the upper surface of the lower base 112.

[0052] Figure 5 The clamping member 150 is shown in a state where it is in a clamping position and clamps the wafer W. Figure 6 yes Figure 5 A magnified schematic diagram of area A in the figure. Figure 6 As shown, in this state, a limiting spoke 511 of the spokes 510 has a first angle a with the first limiting member 160, and the first angle a is within the first angle range. The angle between the limiting spoke 511 and the first limiting member 160 represents the angle between the first rotating member 120 and the first limiting member 160. At the same time, a third angle m is formed between the limiting spoke 511 and the second limiting member 170. The angle between the limiting spoke 511 and the second limiting member 170 represents the angle between the first rotating member 120 and the base 110.

[0053] In this embodiment, the second limiting member 170 is disposed on the right side of the limiting spoke 511, and is used to limit the limit position that the first rotating member 120 can reach when rotating rightward. Figure 6 As shown in , the second limit member further includes a second limit member 171, which is used to limit the extreme position that the first rotating member 120 can reach when rotating leftward.

[0054] Fig. 9 It is a schematic diagram of the state of the wafer chuck device of an embodiment of the present application when the wafer is not clamped, and the clamping member 150 is in a closed position, wherein W' is used to indicate the position where the wafer W should be, and at this time, it is considered that the angle between the base 110 and the first rotating member 120 is 0. Fig.10 yes Fig. 9 The enlarged schematic diagram of area B in the figure. Fig.10As shown, in this state, the limiting spoke 511 contacts the second limiting member 170 so that the first rotating member 120 is blocked and cannot rotate rightward relative to the base 110. At the same time, a second angle c is defined between the limiting spoke 511 and the first limiting member 160, and the second angle c is within a second angle range.

[0055] Fig.11 is a schematic diagram of a curve showing the relationship between the rotation angle and torque of the driving motor 101 during the process of unloading the wafer when the wafer is clamped normally; Fig.12 1 is a schematic diagram of the relationship between the rotation angle and torque of the drive motor 101 during the process of unloading the wafer when the wafer is abnormally clamped. Fig.11 and Fig.12 In the figure, the horizontal axis is the rotation angle of the driving motor 101, and the unit is degree; the vertical axis is the torque output by the driving motor 101, and the unit is Nm. Figure 15A-Figure 15C A schematic diagram showing the process of unloading a wafer when the wafer is clamped normally, wherein: Fig.15A , Fig. 15B , Fig. 15C The states of are sequentially occurred when the wafer is unloaded. In this embodiment, it is assumed that the base 110 is rotated clockwise to open the clamp 150, and the base 110 is rotated counterclockwise to close the clamp 150. Fig.15A As shown, the base 110 is in the HOME position, at this time, the clamping member 150 is in the clamping position, the first limiting member 160 is raised, and the positional relationship between the limiting spoke 511 in the first rotating member 120 and the first limiting member 160 and the second limiting member 170 is as shown in FIG. Figure 5 and Figure 6 As shown, the limiting spoke 511 has a second angle a with the first limiting member 160, and a third angle m with the second limiting member 170. In order to unload the wafer, the driving motor 101 drives the base 110 to rotate in a clockwise direction, and the base 110, the first rotating member 120 and the second rotating member 140 rotate together as a whole, and the stretching length of the elastic member 130 remains unchanged. When the rotation angle of the base 110 and the first rotating member 120 is equal to a, the first rotating member 120 is blocked by the first limiting member 160, as shown in FIG. Fig. 15B As shown, at this time, the base 110 continues to rotate in the clockwise direction, so that the elastic member 130 is stretched, and the torque of the driving motor 101 changes suddenly, as shown in FIG. Fig.11 As shown, when the rotation angle is equal to a, the torque suddenly rises, which is expressed as Fig.11 The vertical line segment 1111 in the figure. By setting a first preset value, the rate of change of the torque with the rotation angle is compared with the first preset value. If the rate of change exceeds the first preset value, it means that the torque has undergone a sudden change. Fig.11, the rotation angle corresponding to the torque mutation is near a. Thereafter, the base 110 continues to rotate in the clockwise direction. As the rotation angle continues to increase, the torque still rises, but the rate of change decreases, as shown by the oblique line segment 1112 in Fig.11 , until the clamping member 150 reaches the preset open position, as shown in Fig. 15C . At this time, the rotation angle of the drive motor 101 is e and the torque is T. The rotation angle e corresponding to the open position can be preset. At the open position, the diameter of the circle surrounded by the plurality of clamping members 150 is greater than the diameter of the wafer W. At this time, the manipulator can unload the wafer or load the wafer when there is no wafer. According to Fig.11 , the first angle range is around a, for example, [a - ε, a + ε], where ε is a tolerance error. If the rotation angle at which the torque mutates during the wafer unloading process is not within this first angle range, it indicates abnormal wafer clamping.

[0056] Figure 16A-16C Schematic diagram of the process of unloading the wafer when wafer clamping is abnormal. When wafer clamping is abnormal, the clamping state of the clamping member 150 is the same as the state of not clamping the wafer, and it is in the closed position. Considering abnormal wafer clamping as equivalent to not clamping the wafer. Fig.16A Used to represent the initial state during the process of unloading the wafer when wafer clamping is abnormal. At this time, the positional relationship between the limiting spoke 511 in the first rotating member 120 and the first limiting member 160 and the second limiting member 170 is as shown in Fig. 9 and Fig.10 . The limiting spoke 511 is in contact with the second limiting member 170, and the first rotating member 120 is restricted by the second limiting member 170 to a limit position. At the same time, there is a first included angle c between the limiting spoke 511 and the first limiting member 160. To unload the wafer, the drive motor 101 drives the base 110 to rotate in the clockwise direction. The base 110, the first rotating member 120, and the second rotating member 140 rotate together as a whole, and the stretching length of the elastic member 130 remains unchanged. When the rotation angle of the base 110 and the first rotating member 120 together is equal to c, the first rotating member 120 is blocked by the first limiting member 160, as shown in Fig. 16B . At this time, the base 110 continues to rotate in the clockwise direction, causing the elastic member 130 to be stretched, and the torque of the drive motor 101 mutates, as shown in Fig.12 . When the rotation angle is equal to c, the torque suddenly rises. At this time, the unloading angle is c, within the second angle range, that is, [c - ε, c + ε], where c < a < e. The second angle range has no intersection with the first angle range. It can be determined that the wafer clamping is abnormal according to the unloading angle within the second angle range. Thereafter, as the rotation angle continues to increase, the torque keeps rising until the clamping member 150 reaches the preset open position, as shown in Fig. 16C . At this time, the rotation angle is e and the torque is T.

[0057] Combination Figure 6 and Fig.10 , the first angle a is equal to the sum of the second angle c and the third angle m.

[0058] Fig.13 is a schematic diagram of a curve showing the relationship between the rotation angle and torque of the driving motor 101 during the process of loading the wafer when the wafer is clamped normally; Fig.14 1 is a schematic diagram of the relationship between the rotation angle and torque of the drive motor 101 during wafer loading when the wafer is abnormally clamped. Fig.13 and Fig.14 In the figure, the horizontal axis is the rotation angle of the drive motor 101, the unit is degree; the vertical axis is the torque output by the drive motor 101, the unit is Nm. Figure 15C-Figure 15A To illustrate Fig.13 The process of loading the wafer when the wafer clamping is normal, Fig. 15C , 15B , 15A occur sequentially when loading the wafer. In this embodiment, Fig. 15C The initial state when loading the wafer is that the clamping member 150 is in the open position. As the reverse process of unloading the wafer, FIG. 15C to FIG. 15A , the total rotation angle of the driving motor 101 is e, Fig. 15C It is used to indicate the initial state of loading the wafer. At this time, the rotation angle of the driving motor 101 is 0, the clamping member 150 is in the open position, and the angle between the limiting spoke 511 and the second limiting member 170 is the fourth angle d. Rotate the base 110 counterclockwise to close the clamping member 150. Fig.13 As shown, the stretching length of the elastic member 130 is gradually shortened, and the torque gradually decreases from T. When the rotation angle reaches about b, b=dm, the clamping member 150 abuts against the edge of the wafer, and the wafer is normally loaded and clamped. At this time, the base 110, the elastic member 130 and the first rotating member 120 are in a balanced state, and the driving motor 101 no longer bears the stress generated by the elastic member 130, so that the torque of the driving motor 101 is suddenly reduced, as shown in FIG. Fig.13 As shown, when the rotation angle reaches b, the torque suddenly decreases, which is expressed as Fig.13 The vertical line segment 1311 in the figure. By setting a second preset value, the rate of change of the torque with the rotation angle is compared with the second preset value. If the rate of change exceeds the second preset value, it means that the torque has a sudden change. Fig.13 When the torque suddenly changes, the corresponding rotation angle is near b. During the process from angle b to angle e, the first rotating member 120 rotates synchronously with the base 110 under the action of the elastic member 130 until reaching Fig.15A In the state shown, the base 110 returns to the HOME position. Fig.13, the third angle range is about b, for example [b-ε, b+ε], where ε is a tolerance error. If the angle when the torque suddenly changes during wafer loading is not within the third angle range, it means that the wafer is clamped normally. That is, the difference between the fourth angle d and the third angle m is within the third angle range.

[0059] In some embodiments, the first preset value and the second preset value have the same absolute value and opposite signs.

[0060] Combination Figure 16C-16A To illustrate Fig.14 The process of loading wafers when wafer clamping is abnormal. Fig. 16C , 16B , 16A occur sequentially when loading a wafer. In this embodiment, Fig. 16C represents the initial state when loading the wafer, at this time, the angle between the limiting spoke 511 and the second limiting member 170 is d, d>b. Fig.14 When the rotation angle of the counterclockwise rotation base 110 is d, the torque of the driving motor 101 suddenly decreases, and the loading angle at this time is within the fourth range, that is, [d-ε, d+ε]. Fig.13 and Fig.14 , b is smaller than d, and [b-ε, b+ε] and [d-ε, d+ε] can be clearly distinguished. By setting reasonable b and d, it can be judged whether the wafer clamping is normal.

[0061] Based on the wafer chuck device 100 described above, a method for detecting a wafer clamping state according to an embodiment of the present application includes the following steps:

[0062] Step S01: in the process of loading and / or unloading wafers, obtaining the relationship between the rotation angle and torque of the driving motor 101;

[0063] Step S02: judging whether the wafer clamping is normal according to the relationship.

[0064] The steps of the detection method have been described in conjunction with the wafer chuck device 100 in the previous text, and the same contents will not be repeated here.

[0065] The application scenarios of this detection method include: the process of unloading the wafer at the end of the previous process, judging whether the wafer clamping is normal in the previous process; the process of loading the wafer at the beginning of the next process, judging whether the wafer clamping is normal in the next process.

[0066] The wafer chuck device 100 and the method for detecting the wafer clamping state of the present application do not require the aid of additional sensor devices. Based on the relationship between the rotation angle and torque that can be obtained by the drive motor 101 itself, the normal or abnormal wafer clamping can be judged according to the corresponding rotation angle when the torque suddenly changes. This has the advantages of simple structure and low cost.

[0067] The basic concepts have been described above. Obviously, for those skilled in the art, the above application disclosure is only an example and does not constitute a limitation of the present application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements and amendments to the present application. Such modifications, improvements and amendments are suggested in the present application, so such modifications, improvements and amendments still belong to the spirit and scope of the exemplary embodiments of the present application.

[0068] At the same time, the present application uses specific words to describe the embodiments of the present application. For example, "one embodiment", "an embodiment", and / or "some embodiments" refer to a certain feature, structure or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned twice or more in different positions in this specification does not necessarily refer to the same embodiment. In addition, some features, structures or characteristics in one or more embodiments of the present application can be appropriately combined.

[0069] Some aspects of the present application may be performed entirely by hardware, entirely by software (including firmware, resident software, microcode, etc.), or by a combination of hardware and software. The above hardware or software may be referred to as "data blocks", "modules", "engines", "units", "components" or "systems". The processor may be one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DAPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, or combinations thereof. In addition, various aspects of the present application may be expressed as computer products located in one or more computer-readable media, which include computer-readable program codes. For example, computer-readable media may include, but are not limited to, magnetic storage devices (e.g., hard disks, floppy disks, tapes ...), optical disks (e.g., compact disks CDs, digital versatile disks DVDs ...), smart cards, and flash memory devices (e.g., cards, sticks, key drives ...).

[0070] A computer-readable medium may include a propagated data signal containing computer program code, such as in baseband or as part of a carrier wave. The propagated signal may have a variety of manifestations, including electromagnetic, optical, etc., or a suitable combination. A computer-readable medium may be any computer-readable medium other than a computer-readable storage medium, which may be connected to an instruction execution system, device or apparatus to communicate, propagate or transmit a program for use. The program code on the computer-readable medium may be propagated via any suitable medium, including radio, cable, fiber optic cable, radio frequency signal, or similar medium, or any combination of the above mediums.

[0071] Similarly, it should be noted that in order to simplify the description of the disclosure of this application and thus help understand one or more embodiments of the invention, in the above description of the embodiments of this application, multiple features are sometimes combined into one embodiment, figure or description thereof. However, this disclosure method does not mean that the features required by the object of this application are more than the features mentioned in the claims. In fact, the features of the embodiments are less than all the features of the single embodiment disclosed above.

[0072] In some embodiments, numbers describing the number of components and attributes are used. It should be understood that such numbers used in the description of the embodiments are modified by the modifiers "about", "approximately" or "substantially" in some examples. Unless otherwise specified, "about", "approximately" or "substantially" indicate that the numbers are allowed to vary by ±20%. Accordingly, in some embodiments, the numerical parameters used in this application are approximate values, which may change according to the required characteristics of individual embodiments. In some embodiments, the numerical parameters should take into account the specified significant digits and adopt the general method of retaining the digits. Although the numerical domains and parameters used to confirm the breadth of the range in some embodiments of the present application are approximate values, in specific embodiments, the setting of such numerical values ​​is as accurate as possible within the feasible range.

[0073] Although the present application has been described with reference to the current specific embodiments, ordinary technicians in this technical field should recognize that the above embodiments are only used to illustrate the present application, and various equivalent changes or substitutions may be made without departing from the spirit of the present application. Therefore, as long as the changes and modifications to the above embodiments are within the essential spirit of the present application, they will fall within the scope of the claims of the present application.

Claims

1. A wafer chuck device, characterized in that: include: A base, a driving motor, a first rotating member, a second rotating member, a clamping member and an elastic member, Wherein, the first rotating member is coaxial with the base, and the driving motor is used to drive the base and the first rotating member to rotate relative to each other; The elastic member has a first end and a second end, the first end is fixedly connected to the base, and the second end is fixedly connected to the first rotating member, and when the base and the first rotating member rotate relative to each other, the elastic member generates stress to make the driving motor generate torque changes; The second rotating member is arranged on the base, the clamping member is arranged on the second rotating member, the second rotating member is in transmission connection with the first rotating member, when the base and the first rotating member rotate relatively, the second rotating member rotates and drives the clamping member to rotate between an open position, a clamping position and a closed position, wherein the clamping position indicates the position of the clamping member when the wafer is clamped; Wherein, the wafer chuck device is configured to output the relationship between the rotation angle and torque of the drive motor during the process of loading and / or unloading the wafer.

2. The wafer chuck device according to claim 1, characterized in that: The wafer chuck device is configured to determine whether the wafer clamping is normal based on the relationship between the rotation angle and torque of the drive motor, wherein the corresponding rotation angle when the torque of the drive motor changes suddenly is different when the wafer clamping is normal and when the wafer clamping is abnormal.

3. The wafer chuck device according to claim 2, characterized in that: The wafer chuck device is also configured as follows: during the process of unloading the wafer, the clamping member is switched to an open position, and when the rate of change of the torque reaches a first preset value, it is determined that a sudden change has occurred in the torque of the drive motor and the corresponding rotation angle is recorded as the unloading angle, and when the unloading angle is within a first angle range, it indicates that the wafer is clamped normally, and when the unloading angle is not within the first angle range, it indicates that the wafer is clamped abnormally.

4. The wafer chuck device according to claim 3, characterized in that: The wafer chuck device is further configured to indicate wafer clamping abnormality when the unloading angle is within a second angle range, wherein the first angle range is greater than the second angle range.

5. The wafer chuck device according to claim 2, characterized in that: The wafer chuck device is also configured as follows: during the process of loading the wafer, the clamping member performs the wafer clamping action from the open position, and when the rate of change of the torque reaches a second preset value, it is determined that the torque of the drive motor has changed suddenly and the corresponding rotation angle is recorded as the loading angle, and when the loading angle is within a third angle range, it indicates that the wafer clamping is normal, and when the loading angle is not within the third angle range, it indicates that the wafer clamping is abnormal.

6. The wafer chuck device according to claim 5, characterized in that: The wafer chuck device is further configured to indicate wafer clamping abnormality when the loading angle is within a fourth angle range, wherein the third angle range is smaller than the fourth angle range.

7. The wafer chuck device according to claim 4, characterized in that: It also includes a first limiting member, which is used to prevent the first rotating member or the base from rotating, so that the first rotating member and the base change from synchronous rotation to relative rotation.

8. The wafer chuck device according to claim 7, characterized in that: When the clamping member is in the clamping position, a first angle is defined between the first rotating member and the first limiting member, and the first angle is within the first angle range.

9. The wafer chuck device according to claim 8, characterized in that: When the clamping member is in the closed position, a second angle (c) is formed between the first rotating member and the first limiting member, and the second angle is within the second angle range.

10. The wafer chuck device according to claim 9, characterized in that: The second angle is smaller than the first angle.

11. The wafer chuck device according to claim 6, wherein: It also includes a second limiting member, which is used to limit the relative position between the base and the first rotating member.

12. The wafer chuck device according to claim 11, wherein: When the clamp is in a closed position, the angle between the base and the first rotating member is 0; when the clamp is in a clamping position, the angle between the base and the first rotating member is a third angle; when the clamp is in an open position, the angle between the base and the first rotating member is a fourth angle, and the fourth angle is within the fourth angle range.

13. The wafer chuck device according to claim 12, wherein: When the wafer is clamped normally, the loading angle is equal to the difference between the fourth angle and the third angle, and the difference between the fourth angle and the third angle is within the third angle range.

14. A method for detecting a wafer clamping state, comprising: During the process of loading and / or unloading the wafer, obtaining the relationship between the rotation angle and the torque of the driving motor; Whether the wafer is clamped normally is determined based on the relationship.

15. The detection method according to claim 14, characterized in that: The step of judging whether the wafer clamping is normal according to the relationship includes judging whether the wafer clamping is normal or abnormal according to the corresponding rotation angle when the torque of the driving motor changes suddenly.

16. The detection method according to claim 15, characterized in that: The steps of judging whether the wafer clamping is normal according to the relationship include: During the process of unloading the wafer, the wafer chuck device is switched to the open state. When the rate of change of the torque reaches a first preset value, it is determined that the torque of the drive motor has changed suddenly and the corresponding rotation angle is obtained as the unloading angle. When the unloading angle is within the first angle range, it indicates that the wafer is clamped normally. When the unloading angle is not within the first angle range, it indicates that the wafer is clamped abnormally.

17. The detection method according to claim 16, characterized in that: Also includes: When the unloading angle is within a second angle range, it indicates that the wafer is clamped abnormally, wherein the first angle range is greater than the second angle range.

18. The detection method according to claim 15, characterized in that: The steps of judging whether the wafer clamping is normal according to the relationship include: During the process of loading the wafer, the wafer chuck device performs a wafer clamping action from an open state. When the rate of change of the torque reaches a second preset value, it is determined that the torque of the drive motor has changed suddenly and the corresponding rotation angle is obtained as the loading angle. When the loading angle is within a third angle range, it indicates that the wafer clamping is normal. When the loading angle is not within the third angle range, it indicates that the wafer clamping is abnormal.

19. The detection method according to claim 18, characterized in that: Also includes: When the loading angle is within a fourth angle range, it indicates that the wafer is clamped abnormally, wherein the third angle range is smaller than the fourth angle range.

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