Substrate centering apparatus and substrate centering method

Abstract

The present invention provides a substrate centering apparatus, used for performing a centering operation on a square substrate. The apparatus comprises: two centering operation assemblies, respectively acting on two corners of a substrate in a preselected diagonal direction, wherein each centering operation assembly comprises a first arm and a second arm parallel to each other; the two centering operation assemblies are configured such that one centering operation assembly first linearly moves to a target position so as to act on one corner of a preselected diagonal line, and the other centering operation assembly then linearly moves to the target position so as to act on the other corner of the preselected diagonal line, so that the center of the substrate coincides with the rotation center of the substrate; each centering operation assembly uses the intersection of the extension lines of the first arm and the second arm to two edges of a corresponding corner of the substrate located at a preset position as the target position; the two centering operation assemblies act on the two corners of the substrate in the preselected diagonal direction so as to correct the position of the substrate. In this way, the position of the substrate is accurately and quickly positioned.

Description

Substrate centering device and substrate centering method

[0001] This application claims priority to Chinese Patent Application No. 202411362921.2, filed September 26, 2024, the contents of which are incorporated herein by reference in their entirety. TECHNICAL FIELD

[0002] The present application belongs to the technical field of semiconductor, and relates to a substrate centering device and a substrate centering method. BACKGROUND

[0003] In a substrate processing process, the substrate needs to be accurately positioned before the process of the substrate can be facilitated. For example, when the substrate is subjected to edge washing, the substrate is accurately positioned, and the position of the chemical liquid sprayed by the nozzle relative to the substrate can be accurately controlled. If the substrate is not positioned accurately, when the substrate is rotated, the position of the chemical liquid sprayed by the nozzle relative to the substrate is not accurate, which affects the edge washing effect of the substrate, such as uneven edge washing width, etc. Before the substrate is subjected to other process treatments, the substrate also needs to be positioned first. Therefore, accurately positioning the substrate has become one of the technical problems to be solved by those skilled in the art.

[0004] Therefore, in view of the problems existing in the prior art, the present application is designed by the inventor with years of experience in this field, and actively improves the prior art, thereby providing a substrate centering device and a substrate centering method. SUMMARY

[0005] In view of the above-mentioned shortcomings of the prior art, the purpose of the present application is to provide a substrate centering device and a substrate centering method to solve the problem of inaccurate positioning of the substrate in the prior art.

[0006] To achieve the above-mentioned purpose and other related purposes, the present application provides a substrate centering device for square substrate centering operation, comprising:

[0007] a substrate holding member for holding and rotating the substrate;

[0008] two centering operation assemblies acting on two top corners in a preselected diagonal direction of the substrate, respectively;

[0009] Each centering operation assembly comprises a first arm and a second arm parallel to each other, and the first arm and the second arm of each centering operation assembly make linear motion on both sides of a middle parallel line determined by the first arm and the second arm, so that each centering operation assembly acts on the corresponding top corner in the preselected diagonal direction of the two top corners, and the middle parallel line passes through the rotation center of the substrate.

[0010] The two alignment operation assemblies are configured to move linearly to target positions to act on two opposite corners of the preselected diagonal line, and then move linearly to target positions to act on the other two opposite corners of the preselected diagonal line, so that the center of the substrate coincides with the rotation center of the substrate, and each alignment operation assembly determines the target position as the intersection of the extension line of the first arm and the extension line of the second arm to the corresponding corner of the substrate in the preselected position.

[0011] Optionally, the intersection is not more than the midpoint of the side of the substrate on which the corresponding arm acts.

[0012] Optionally, the end of the first arm is provided with a first roller for contacting the substrate, and the end of the second arm is provided with a second roller for contacting the substrate, and the first roller and the second roller are configured to maintain contact with the substrate and rotate synchronously when contacting and displacing the substrate.

[0013] Optionally, the arm length of the first arm is configured according to the stroke of the first roller, and the arm length of the second arm is configured according to the stroke of the second roller.

[0014] Optionally, at the target position of the alignment operation assembly, the distance Y1 between the end of the first arm and the corresponding corner in the linear motion direction of the first arm and the distance Y2 between the end of the second arm and the corresponding corner in the linear motion direction of the second arm satisfy the following formula:

[0015] wherein the side of the substrate on which the first arm acts is a first side, the side of the substrate on which the second arm acts is a second side, a is the length of the first side, b is the length of the second side, and L is the distance between the first arm and the second arm.

[0016] Optionally, the arm length L1 of the first arm and the arm length L2 of the second arm satisfy the following formula:

[0017] wherein R is the radius of the first roller and the second roller.

[0018] Optionally, each alignment operation assembly further comprises a support portion for supporting the first arm and the second arm, and a driving portion for driving the support portion to translate so that the first arm and the second arm move linearly.

[0019] Optionally, each alignment operation assembly further comprises a flexible protective cover for protecting the driving portion, the flexible protective cover extending along the translation direction of the support portion, so that the flexible protective cover expands and contracts synchronously when the support portion translates.

[0020] Optionally, a length of the edge on which the first arm acts on the substrate is a, a length of the edge on which the second arm acts on the substrate is b, if a = b, the arm length of the first arm is configured to be equal to the arm length of the second arm; if a > b, the arm length of the first arm is configured to be greater than the arm length of the second arm; if a < b, the arm length of the first arm is configured to be less than the arm length of the second arm.

[0021] To achieve the above object and other related objects, the present application further provides a substrate centering method, which is suitable for a substrate centering device, the substrate centering device comprising a substrate holder for holding and rotating the substrate, and two centering operation assemblies for acting on two top corners in a preselected diagonal direction of the substrate respectively, wherein each centering operation assembly comprises a first arm and a second arm which are parallel to each other, and the method comprises:

[0022] linearly moving one centering operation assembly to a target position to act on one top corner in the preselected diagonal direction of the substrate;

[0023] linearly moving the other centering operation assembly to the target position to act on the other top corner in the preselected diagonal direction, so that the center of the substrate coincides with the rotation center of the substrate;

[0024] wherein the first arm and the second arm of each centering operation assembly are linearly moved along two sides of a middle parallel line determined by the first arm and the second arm respectively, so that each centering operation assembly acts on a corresponding top corner of the two top corners in the preselected diagonal direction, the middle parallel line passes through the rotation center of the substrate, and each centering operation assembly determines the target position at an intersection point of an extension line of the first arm and an extension line of the second arm to two sides of the corresponding top corner of the substrate located at the preselected position.

[0025] Optionally, the intersection point is not more than a midpoint of the edge of the substrate on which each arm acts.

[0026] Optionally, an end of the first arm is provided with a first roller for contacting the substrate, an end of the second arm is provided with a second roller for contacting the substrate, and the method further comprises keeping the first roller and the second roller in contact with the substrate and rotating synchronously when the first roller and the second roller are in contact with the substrate and displace the substrate.

[0027] Optionally, the arm length of the first arm is configured according to the stroke of the first roller, and the arm length of the second arm is configured according to the stroke of the second roller.

[0028] Optionally, in the target position of the centering assembly, the distance Y1 between the first arm end and the corresponding vertex in the linear motion direction of the first arm and the distance Y2 between the second arm end and the corresponding vertex in the linear motion direction of the second arm satisfy the following formula:

[0029] wherein the first arm acts on the first side of the substrate, the second arm acts on the second side of the substrate, a is the length of the first side, b is the length of the second side, and L is the distance between the first arm and the second arm.

[0030] Optionally, the length L1 of the first arm and the length L2 of the second arm satisfy the following formula:

[0031] wherein R is the radius of the first roller and the second roller.

[0032] As described above, the substrate centering device and the substrate centering method of the present application, two centering assembly act on two vertices of the substrate in the preselected diagonal direction to correct the position of the substrate, and the centering operation of four sides of the substrate is completed by translating the two centering assembly once, which simplifies the substrate centering operation process and accurately moves the substrate to the centering position.

[0033] SUMMARY

[0034] The features and performances of the present application are further described by the following embodiments and the accompanying drawings.

[0035] Fig. 1 is a structural schematic diagram of the substrate centering device of an embodiment of the present application in the non-centering operation state.

[0036] Fig. 2 is a schematic diagram of the substrate centering device and the substrate in the state of the completion of the centering operation of an embodiment of the present application.

[0037] Fig. 3 is a structural schematic diagram of the centering assembly of an embodiment of the present application.

[0038] Fig. 4 is a detailed view of the embodiment of Fig. 3 of the present application.

[0039] Fig. 5 is a schematic diagram of the centering operation of two centering assemblies of the prior art.

[0040] Preferred embodiments of the present application

[0041] Following, the advantages and effects of the present application will be easily understood by those skilled in the art from the description of the embodiments of the present application. The present application can also be implemented or applied by other different embodiments, and the details in the description can be modified or changed based on different views and applications without departing from the spirit of the present application.

[0042] As described in the detailed description of the embodiments of the present application, the cross-sectional views of the device structure are partially enlarged without the general scale for the convenience of explanation, and the schematic views are only examples which should not limit the scope of the present application. In addition, the three-dimensional spatial dimensions of length, width and depth should be included in the actual fabrication.

[0043] For the convenience of description, spatial relationship words such as "under", "below", "lower", "lower than", "underneath", "above", "upper", "on", and the like can be used herein to describe the relationship of one element or feature to other elements or features shown in the drawings. It will be understood that these spatial relationship words are intended to include other orientations of the device in use or operation in addition to the orientations depicted in the drawings. In addition, when a layer is referred to as being "between" two layers, it can be the only layer between the two layers, or one or more intervening layers can also exist. "Between" as used herein is inclusive of both endpoints.

[0044] In the context of the present application, the structure described as the first feature being "on" the second feature can include the embodiment in which the first and second features are formed in direct contact, and can also include the embodiment in which additional features are formed between the first and second features, so that the first and second features can not be in direct contact.

[0045] It should be noted that the diagrams provided in the embodiments only schematically illustrate the basic concepts of the present application, and only the components related to the present application are shown in the diagrams, not the number, shape and size of the components when actually implemented. The shapes, number and proportions of the components when actually implemented can be arbitrarily changed, and the layout pattern of the components can be more complex. The substrate centering device and the substrate centering method are used for the operation of the substrate in the field of semiconductor wafers or flat panel displays (FPD).

[0046] Referring to FIG. 1, the substrate centering device includes two centering operation assemblies 1 performing centering operation on a substrate W and a substrate holder 3 holding and rotating the substrate W. The substrate W in the present application is square or rectangular. The centering operation in the present application is the position correction of the substrate W by the two centering operation assemblies 1 so that the center o of the substrate coincides with the rotation center o' of the substrate W. At this time, the position of the substrate is the centered position. Before processing the substrate, the substrate W needs to be positioned so that the center o of the substrate coincides with the rotation center o' of the substrate W to accurately position the processing position of the substrate W during rotation of the substrate W. The substrate holder 3 drives the substrate W to rotate around the axis passing through the rotation center o'.

[0047] Referring to FIG. 3 in combination with FIG. 1, the centering operation assembly 1 includes two arms 13 arranged in parallel with each other, a support portion 12 supporting the two arms 13, and a driving portion 11 driving the support portion 12 to translate so as to translate the two arms 13. The end of each arm 13 is provided with a roller 14 for contacting the substrate W. When the two centering operation assemblies 1 are used to perform centering operation on the substrate W, the substrate W is displaced, and the rollers 14 contacting the substrate W rotate synchronously to prevent damage caused by friction between the centering operation assemblies 1 and the edges of the substrate W. The roller 14 is preferably made of a material that is not easy to deform and does not contain impurities such as metal, for example, a ceramic material. The driving portion 11 includes a power portion (not shown) providing power to the support portion 12 and a horizontal slide rail (not shown) guiding the support portion 12 to slide in the horizontal direction. The support portion 12 slides along the horizontal slide rail so that the two arms 13 connected to the support portion 12 are simultaneously driven to slide towards or away from the substrate W. The power portion can be selected from an electric cylinder, a pneumatic cylinder, a motor, etc. The centering operation assembly 1 further includes a flexible protective cover 15 arranged above the driving portion 11 to protect the driving portion 11. The flexible protective cover 15 is fixed at both ends, and the support portion 12 extends outward from the driving portion 11 and passes through the flexible protective cover 15. Specifically, the flexible protective cover 15 extends in the translation direction of the support portion 12 so that the flexible protective cover 15 expands and contracts synchronously when the support portion 12 is translated by the power portion. The driving portion 11 can be arranged outside or inside the process chamber 2. Preferably, the driving portion 11 is arranged outside the process chamber 2 for easy maintenance and repair in the later stage. In this preferred embodiment, the process chamber 2 is left with an opening of a certain length so that the support portion 12 passes through the opening and moves linearly along the extension direction of the opening. The flexible protective cover 15 can prevent the driving portion 11 from being corroded by the raw materials used to process the substrate W in the process chamber 2, for example, the driving portion 11 can be corroded by dilute sulfuric acid contained in the raw materials.

[0048] As shown in FIG. 1, the two arms 13 of the centering operation assembly 1 move linearly along the two sides of the middle parallel line D defined by the two arms 13 and act on one of the two top corners of the preselected diagonal direction of the substrate W. Specifically, the two arms move linearly along the respective extension directions indicated by D1 and D2, wherein the first arm 131 extends along D2 and the second arm 132 extends along D1, and the middle parallel line between the first arm 131 and the second arm 132 is indicated by the mark D. The middle parallel line D passes through the rotation center o' of the substrate, and through the centering operation of the centering operation assembly 1, the center o of the substrate coincides with the rotation center o' of the substrate. The two centering operation assemblies 1 are respectively used to operate the two top corners of the preselected diagonal direction of the substrate W, and each centering operation assembly 1 is respectively used to contact two edges of the corresponding top corner to move the substrate W so that the center o of the substrate coincides with the rotation center o' of the substrate. One of the centering operation assemblies 1 acts on two edges of one top corner, and the other centering operation assembly 1 acts on two edges of the other top corner. Since the two top corners acted on are located in the same diagonal direction, the centering operation of the four edges of the substrate is completed by translating the two centering operation assemblies 1 once, thereby avoiding the need to translate the two centering operation assemblies 1 twice to complete the centering operation of the two groups of opposite edges of the substrate W as shown in FIG. 5. Therefore, the use of the substrate centering device and the substrate centering method of the present application simplifies the substrate centering operation process. The centering operation performed by the two centering operation assemblies 1 on the substrate W is that any one centering operation assembly 1 moves linearly in the direction close to the substrate W to a target position, and the other centering operation assembly 1 moves linearly in the direction close to the substrate W to a target position to correct the position of the substrate W, so that when the substrate moves to the preset position, the center of the substrate coincides with the rotation center of the substrate. Among them, the two centering operation assemblies act on the two top corners of the preselected diagonal direction, and the target position of the centering operation assembly is determined according to the relative position of the corresponding top corner of the preselected diagonal direction when the centering operation assembly and the substrate are in the preset position to realize the centering operation of the substrate. The target position of the movement of each centering operation assembly 1 will be described in detail below. It should be understood that if the lengths of the adjacent edges of the same substrate are different, the position of each top corner of the substrate relative to the centering operation assembly 1 will also be different, so the target position of the centering operation assembly needs to be determined according to the two top corners of the preselected diagonal direction and act on the two top corners of the preselected diagonal direction to realize the centering operation.

[0049] As shown in Fig. 2, after the two alignment operation assemblies 1 align the substrate W, the substrate W is moved to a preset alignment position. At this time, the two rollers 141, 142 of each alignment operation assembly 1 are clamped on both sides of the corresponding top corner of the substrate W. Each alignment operation assembly 1 comprises a first arm 131, a second arm 132, a first roller 141 at the end of the first arm 131 and acting on the edge a of the substrate, and a second roller 142 at the end of the second arm 132 and acting on the edge b of the substrate. During the alignment operation, one alignment operation assembly first moves linearly to a target position to act on one top corner of a preselected diagonal line, and the other alignment operation assembly then moves linearly to the target position to act on the other top corner of the preselected diagonal line, so that the center of the substrate coincides with the rotation center of the substrate. The target position of each alignment operation assembly is the intersection point of the extension line of the first arm and the extension line of the second arm to the corresponding top corner on both sides of the preset position of the substrate. Taking one of the alignment operation assemblies as an example, as shown in Fig. 4, after the alignment operation assembly moves to the target position and aligns the substrate, the substrate has been moved to the preset alignment position. At this time, the target position of the first arm 131 is determined by the intersection point a1 of the extension line 131a of the first arm 131 and the edge a of the substrate, and the target position of the second arm 132 is determined by the intersection point b1 of the extension line 132b of the second arm 132 and the edge b of the substrate, and finally the target position of the alignment operation assembly is determined. When the first arm 131 and the second arm 132 are at the target position, the distances between the end of the first arm 131, the end of the second arm 132 and the top corner of the substrate W in the linear motion direction (see D2, D1 in Fig. 1) of the first arm 131 and the second arm 132 are Y2 and Y1 respectively. Wherein, the length of the edge a (first edge) is a, the length of the edge b (second edge) is b, the included angle between the preselected diagonal line and the edge b of the substrate at the preset position is θ, the radius of the first roller 141 and the second roller 142 is R. The distance between the first arm 131 and the second arm 132 is L, and the distance between the first arm 131 and the second arm 132 to the middle parallel line D is L / 2, so that Y1*tanθ+R / cosθ=L / 2

[0050] Then, Y1=(L / 2-R / cosθ) / tanθ

[0051] Combined with the trigonometric function tanθ=a / b

[0052] Similarly,

[0053] Thus,

[0054] The above two equations are transformed respectively to obtain

[0055] Subtracting the two equations above, we get 2aY1-2bY2=bL-aL

[0056] The relationship between the distances Y2 and Y1 between the end of the first arm 131, the end of the second arm 132 and the top corner of the substrate W satisfies the following relationship

[0057] From the relationship between Y1 and Y2, if the two sides a and b of the substrate are equal, then Y2=Y1; if a>b, then Y2>Y1; if a To prevent the substrate W from interfering with the centering operation assembly 1 during the transmission to the process chamber 2 or during rotation, the centering operation assembly 1 is moved to a position outside the maximum movement range of the top corner of the substrate W when the substrate centering operation is completed or when the centering operation is not performed. Therefore, the arm length L1 of the first arm 131 is configured to be greater than or equal to R+Y2, in addition to the distance R+Y2 from the position where the first roller 141 contacts the substrate when the substrate is centered to the corresponding vertex A of the top corner. Therefore, the arm length L1 of the first arm 131 is greater than or equal to R+Y2. Similarly, the arm length L2 of the second arm 132 is configured to be greater than or equal to R+Y1. In some embodiments, to protect the centering operation assembly 1, the centering operation assembly 1 can be translated outside the process chamber 2 when the substrate centering operation is completed or before the centering operation. Therefore, according to the stroke of the first roller 141 and the second roller 142, as shown in FIG. 4, the arm lengths of the first arm 131 and the second arm 132 need to be increased by the length S0 from the top vertex A of the substrate to the outside of the process chamber 2. That is, at this time, the arm lengths L1 and L2 of the first arm 131 and the second arm 132 are R+Y2+S0 and R+Y1+S0, respectively. It can be seen that the comparison result of the arm lengths L1 and L2 of the first arm 131 and the second arm 132 is equivalent to the comparison result of Y2 and Y1. Therefore, if the two sides a and b of the substrate are equal, the arm lengths of the first arm 131 and the second arm 132 are equal; if a>b, the arm length L1 of the first arm 131 is greater than the arm length L2 of the second arm 132; if a

[0058] Similarly, in another centering operation assembly 1, the first arm 131 and the first roller 141 act on the a side (the first side), and the second arm 132 and the second roller 142 act on the b side (the second side), and the arm lengths are set the same as the above-mentioned centering operation assembly, which will not be described here.

[0059] In summary, from another perspective, the substrate centering method comprises the following steps:

[0060] (1) one of the centering operation assemblies is linearly moved to a target position to act on one of the top corners of the corresponding diagonal line of the substrate;

[0061] (2) the other of the centering operation assemblies is linearly moved to a target position to act on the other of the top corners of the corresponding diagonal line of the substrate, so that the center of the substrate coincides with the rotation center of the substrate, wherein the first arm and the second arm of each of the centering operation assemblies are linearly moved along two sides of a middle parallel line determined by the first arm and the second arm respectively, so that each of the centering operation assemblies acts on the top corner corresponding to the preselected diagonal line of the substrate, the middle parallel line passes through the rotation center of the substrate, and each of the centering operation assemblies determines the target position by the intersection of the extension line of the first arm and the extension line of the second arm to the preselected position of the substrate on two sides of the corresponding top corner.

[0062] In step (2), as shown in FIG. 4, the substrate is in the centering position at the preselected position, at this time, taking one of the centering operation assemblies as an example, the target position of the first arm 131 is determined according to the position of the intersection a1 of the extension line 131a of the first arm 131 and the a side (the first side) relative to the first arm 131, and the target position of the second arm 132 is determined according to the position of the intersection b1 of the extension line 131b of the second arm 131 and the b side (the second side) relative to the second arm 132, so as to obtain the target position of one of the centering operation assemblies. The target position of the other of the centering operation assemblies is set in the same way as the target position of the above-mentioned centering operation assembly, which is not described here. Preferably, in order to avoid that the distance between the first arm 131 and the second arm 132 is too large to increase the space occupied by the centering operation assemblies, the intersection a1 does not exceed the midpoint of the a side, and the intersection b1 does not exceed the midpoint of the b side.

[0063] More details of the method embodiment can be referred to the description of the substrate centering device above, which is not described here.

[0064] The above embodiments only exemplarily illustrate the principles and effects of the present application, and are not used to limit the present application. Any person skilled in the art can modify or change the above embodiments without departing from the spirit and scope of the present application. Therefore, all equivalent modifications or changes completed by those skilled in the art without departing from the spirit and technical thought disclosed by the present application should be covered by the claims of the present application.

Claims

1. A substrate centering device for a square substrate centering operation, characterized by comprising: The method comprises the following steps: a substrate holder for holding and rotating the substrate; two centering operation assemblies acting on two top corners of a preselected diagonal direction of the substrate respectively; wherein each centering operation assembly comprises a first arm and a second arm parallel to each other, the first arm and the second arm of each centering operation assembly make linear motion on both sides of a middle parallel line determined by the first arm and the second arm, so that each centering operation assembly acts on a corresponding top corner of the preselected diagonal direction, and the middle parallel line passes through the rotation center of the substrate; the two centering operation assemblies are configured to make linear motion to a target position to act on one top corner of the preselected diagonal direction, and then make linear motion to a target position to act on the other top corner of the preselected diagonal direction, so that the center of the substrate coincides with the rotation center of the substrate, and each centering operation assembly determines the target position at the intersection of the extension line of the first arm and the extension line of the second arm to the two sides of the corresponding top corner of the substrate in the preset position.

2. The substrate centering device of claim 1, wherein, The intersection is not more than the midpoint of the side of the substrate on which the corresponding arm acts.

3. The substrate centering device of claim 1, wherein, The end of the first arm is provided with a first roller for contacting the substrate, and the end of the second arm is provided with a second roller for contacting the substrate, and the first roller and the second roller are configured to contact and displace the substrate while keeping contact with the substrate and rotating synchronously.

4. The substrate centering device of claim 3, wherein, The arm length of the first arm is configured according to the stroke of the first roller, and the arm length of the second arm is configured according to the stroke of the second roller.

5. The substrate centering device of claim 3, wherein, At the target position of the pair of operating assemblies, the distance Y1 between the first arm tip and the corresponding vertex in the linear motion direction of the first arm and the distance Y2 between the second arm tip and the corresponding vertex in the linear motion direction of the second arm satisfy the following formula: Wherein, the first arm acts on a first side of the substrate, the second arm acts on a second side of the substrate, a is the length of the first side, b is the length of the second side, and L is the distance between the first arm and the second arm.

6. The substrate centering device of claim 5, wherein, The arm length LI of the first arm and the arm length L2 of the second arm satisfy the following formula: Wherein, R is the radius of the first roller and the second roller.

7. The substrate centering device of claim 1, wherein Each centering operation assembly further comprises a support portion for supporting the first arm and the second arm, and a driving portion for driving the support portion to translate so as to make the first arm and the second arm make linear motion.

8. The substrate centering device of claim 7, wherein, Each centering operation assembly further comprises a flexible protective cover for protecting the driving portion, the flexible protective cover extends along the translation direction of the support portion, so that the flexible protective cover expands and contracts synchronously when the support portion translates.

9. The substrate centering device of claim 1, wherein, If a = b, the arm length of the first arm is configured to be equal to the arm length of the second arm; if a > b, the arm length of the first arm is configured to be greater than the arm length of the second arm; if a < b, the arm length of the first arm is configured to be less than the arm length of the second arm.

10. A substrate centering method, adapted for a substrate centering apparatus, the substrate centering apparatus comprising a substrate holder for holding and rotating a substrate, two centering operation assemblies acting on two apex corners of the substrate respectively in preselected diagonal directions, wherein, Each centering operation assembly comprises a first arm and a second arm parallel to each other, and the method comprises the following steps: one centering operation assembly makes linear motion to a target position to act on one top corner of a preselected diagonal direction of the substrate; Another of the centering operation assemblies moves linearly to a target position to act on another vertex angle in the preselected diagonal direction, so that the center of the substrate coincides with the rotation center of the substrate; Wherein the first arm and the second arm of each centering operation assembly move linearly along two sides of a middle parallel line determined by the first arm and the second arm, respectively, so that the each centering operation assembly acts on a corresponding vertex angle of the two vertex angles in the preselected diagonal direction, the middle parallel line passing through the rotation center of the substrate, each centering operation assembly determining a target position at an intersection of an extension line of the first arm and an extension line of the second arm to two sides of a corresponding vertex angle of the substrate at a preset position.

11. The method of claim 10, wherein, The intersection is not more than a midpoint of an edge of the substrate on which each arm acts.

12. The method of claim 10, wherein, The end of the first arm is provided with a first roller for contacting the substrate, and the end of the second arm is provided with a second roller for contacting the substrate, and the method further comprises keeping the first roller and the second roller in contact with the substrate and rotating synchronously when the first roller and the second roller are in contact with the substrate and displace the substrate.

13. The method of claim 12, wherein, The arm length of the first arm is configured according to the stroke of the first roller, and the arm length of the second arm is configured according to the stroke of the second roller.

14. The method of claim 12, wherein, At the target position of the pair of operating assemblies, the distance Y1 between the first arm tip and the corresponding vertex in the linear motion direction of the first arm and the distance Y2 between the second arm tip and the corresponding vertex in the linear motion direction of the second arm satisfy the following formula: Wherein, the edge on which the first arm acts on the substrate is a first edge, the edge on which the second arm acts on the substrate is a second edge, a is the length of the first edge, b is the length of the second edge, and L is the distance between the first arm and the second arm.

15. The method of claim 14, wherein, The arm length LI of the first arm and the arm length L2 of the second arm satisfy the following formula: Wherein, R is the radius of the first roller and the second roller.

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