Pre-alignment eccentricity calibration method, device and equipment based on wafer pre-alignment device and medium

Abstract

The invention discloses a pre-alignment eccentricity calibration method and device based on a wafer pre-alignment device, equipment and a medium. The pre-alignment eccentricity calibration method comprises the following steps: acquiring wafer fitting radiuses when a wafer edge distance sensor rotates to different positions; determining a minimum wafer fitting radius according to the plurality of wafer fitting radiuses; determining an actual distance between a first actual rotation center of the wafer edge distance sensor and a second actual rotation center of the wafer rotating table according to the minimum wafer fitting radius; controlling the wafer edge distance sensor to be fixed at the position of the wafer edge distance sensor corresponding to the minimum wafer fitting radius, so that the second actual rotation center is located on the measurement axis; and controlling the second actual rotation center to coincide with the ideal rotation center of the wafer rotating table according to the actual distance. By adopting the pre-alignment eccentricity calibration method, the accuracy of wafer pre-alignment can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of wafer pre-alignment, and in particular to a pre-alignment eccentricity calibration method, device, equipment and medium based on a wafer pre-alignment device. Background Art

[0002] In the wafer pre-alignment system, due to the installation error of the wafer edge distance sensor and the installation error of the wafer turntable, the straight line where the measuring axis of the wafer edge distance sensor is located is not colinear with the actual rotation center of the wafer turntable. The actual rotation center of the wafer turntable does not coincide with the theoretical rotation center on the measuring axis of the wafer edge distance sensor. There is a deviation, which will lead to a decrease in the wafer centering accuracy, thereby affecting the transmission of the wafer. Summary of the invention

[0003] The present invention provides a pre-alignment eccentricity calibration method, device, equipment and medium based on a wafer pre-alignment device, so as to solve the problem of low wafer pre-alignment accuracy caused by pre-alignment eccentricity.

[0004] In a first aspect, an embodiment of the present invention provides a pre-alignment eccentricity calibration method based on a wafer pre-alignment device, wherein the wafer pre-alignment device comprises a wafer edge distance sensor and a wafer rotation table, wherein the wafer edge distance sensor rotates around a first actual rotation center, and the wafer rotation table rotates around a second actual rotation center, and the ideal rotation center of the wafer rotation table and the first actual rotation center are both located on the measurement axis of the wafer edge distance sensor, and the pre-alignment eccentricity calibration method comprises:

[0005] Obtaining the wafer fitting radius when the wafer edge distance sensor is rotated to different positions;

[0006] Determining a minimum wafer fitting radius according to the plurality of wafer fitting radiuses;

[0007] Determine an actual distance between the first actual rotation center and the second actual rotation center according to the minimum wafer fitting radius;

[0008] Controlling the wafer edge distance sensor to be fixed at a wafer edge distance sensor position corresponding to the minimum wafer fitting radius, so that the second actual rotation center is located on the measurement axis;

[0009] The second actual rotation center is controlled to coincide with the ideal rotation center according to the actual distance.

[0010] Optionally, obtaining the wafer fitting radius when the wafer edge distance sensor is rotated to different positions includes:

[0011] Obtaining an i-th wafer fitting radius of the wafer edge distance sensor at an i-th position, where i≥1;

[0012] Controlling the wafer edge distance sensor to rotate along the i-th rotation direction by the i-th preset angle to the (i+1)-th position, and obtaining the (i+1)-th wafer fitting radius of the wafer edge distance sensor at the (i+1)-th position; the i-th rotation direction includes a clockwise direction or a counterclockwise direction;

[0013] Determining the (i+1)th rotation direction and the (i+1)th rotation angle of the wafer edge distance sensor according to the magnitude relationship between the i-th wafer fitting radius and the (i+1)-th wafer fitting radius; the (i+1)-th rotation direction includes a clockwise direction or a counterclockwise direction;

[0014] The wafer edge distance sensor is controlled to rotate along the (i+1)th rotation direction by the (i+1)th preset angle to the (i+2)th position, and the (i+2)th wafer fitting radius of the wafer edge distance sensor at the (i+2)th position is obtained.

[0015] Optionally, obtaining the i-th wafer fitting radius of the wafer edge distance sensor at the i-th position includes:

[0016] When the wafer edge distance sensor is at the i-th position, controlling the wafer rotating table to rotate at least one circle;

[0017] Acquiring i-th distance information between the edge of the wafer and the ideal rotation center and i-th rotation angle information of the wafer rotation table during the rotation of the wafer rotation table;

[0018] The i-th wafer fitting radius is determined according to the i-th distance information and the i-th rotation angle information.

[0019] Optionally, determining the i-th wafer fitting radius according to the i-th distance information and the i-th rotation angle information includes:

[0020] An i-th fitting circle is fitted according to the i-th distance information and the i-th rotation angle information, and the radius of the i-th fitting circle is the i-th wafer fitting radius.

[0021] Optionally, determining the (i+1)th rotation direction and the (i+1)th rotation angle of the wafer edge distance sensor according to the size relationship between the i-th wafer fitting radius and the (i+1)-th wafer fitting radius includes:

[0022] If the i-th wafer fitting radius is smaller than the (i+1)-th wafer fitting radius, it is determined that the (i+1)-th rotation direction is the same as the i-th rotation direction, and the (i+1)-th rotation angle is the same as the i-th preset angle;

[0023] If the i-th wafer fitting radius is greater than the (i+1)-th wafer fitting radius, it is determined that the (i+1)-th rotation direction is opposite to the i-th rotation direction, and the (i+1)-th rotation angle is the same as the i-th preset angle;

[0024] If the i-th wafer fitting radius is equal to the (i+1)-th wafer fitting radius, it is determined that the (i+1)-th rotation direction is opposite to the i-th rotation direction, and the (i+1)-th rotation angle is less than the i-th preset angle.

[0025] Optionally, determining the actual distance between the first actual rotation center and the second actual rotation center according to the minimum wafer fitting radius includes:

[0026] The actual distance is determined according to the minimum wafer fitting radius and the following corresponding relationship:

[0027] L 1 =R+L 0 -r min ;

[0028] L 1 represents the actual distance, R represents the radius of the wafer, L 0 represents the preset distance between the first actual rotation center and the ideal rotation center, r min It represents the minimum wafer fitting radius.

[0029] Optionally, controlling the second actual rotation center to coincide with the ideal rotation center according to the actual distance includes:

[0030] Determining a moving direction and a moving distance of the wafer rotation stage according to the actual distance and a preset distance between the first actual rotation center and the ideal rotation center;

[0031] The movement of the wafer stage is controlled according to the moving direction and the moving distance.

[0032] In a second aspect, an embodiment of the present invention provides a pre-alignment eccentricity calibration device, which is used to perform the pre-alignment eccentricity calibration method as described in the first aspect, and the pre-alignment eccentricity calibration device includes:

[0033] A wafer fitting radius acquisition unit, used for acquiring the wafer fitting radius when the wafer edge distance sensor is rotated to different positions;

[0034] A minimum wafer fitting radius determining unit, used to determine a minimum wafer fitting radius according to a plurality of the wafer fitting radii;

[0035] an actual distance determining unit, configured to determine an actual distance between the first actual rotation center and the second actual rotation center according to the minimum wafer fitting radius;

[0036] a wafer edge distance sensor calibration unit, used for controlling the wafer edge distance sensor to be fixed at a wafer edge distance sensor position corresponding to the minimum wafer fitting radius so that the second actual rotation center is located on the measurement axis;

[0037] A rotation center calibration unit is used to control the second actual rotation center to coincide with the ideal rotation center according to the actual distance.

[0038] In a third aspect, an embodiment of the present invention provides a pre-alignment eccentricity calibration device, the pre-alignment eccentricity calibration device comprising:

[0039] one or more processors;

[0040] a storage device for storing one or more programs,

[0041] When the one or more programs are executed by the one or more processors, the one or more processors implement the pre-alignment eccentricity calibration method as described in the first aspect.

[0042] In a fourth aspect, an embodiment of the present invention provides a storage medium having a computer program stored thereon, wherein when the computer program is executed by a processor, the pre-alignment eccentricity calibration method as described in the first aspect is implemented.

[0043] The technical solution of the embodiment of the present invention fixes the wafer edge distance sensor at a position corresponding to the minimum wafer fitting radius during its rotation around the first rotation center, and controls the second actual rotation center of the wafer rotation table to coincide with its ideal rotation center according to the actual distance, so that the second actual rotation center of the wafer rotation table is located on the measuring axis of the wafer edge distance sensor and coincides with the ideal rotation center. This solves the problem that in the existing wafer pre-alignment process, due to the installation error of the wafer edge distance sensor and the wafer rotation table, the straight line where the measuring axis of the wafer edge distance sensor is located is not colinear with the second actual rotation center of the wafer rotation table, and the second actual rotation center of the wafer rotation table does not coincide with the theoretical rotation center located on the measuring axis of the wafer edge distance sensor, thereby causing a decrease in the accuracy of wafer pre-alignment. This is beneficial to improving the accuracy of wafer pre-alignment.

[0044] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0046] Figure 1 A schematic structural diagram of a wafer pre-alignment device provided by an embodiment of the present invention;

[0047] Figure 2 A flowchart of a pre-alignment eccentricity calibration method based on a wafer pre-alignment device provided in an embodiment of the present invention;

[0048] Figure 3 A schematic plan view of an initial state of wafer pre-alignment provided by an embodiment of the present invention;

[0049] Figure 4 A schematic plan view of a calibration state of wafer pre-alignment provided by an embodiment of the present invention;

[0050] Figure 5 for Figure 3 and Figure 4 A simplified diagram of the provided wafer pre-alignment plan view;

[0051] Figure 6 A flow chart of another pre-alignment eccentricity calibration method based on a wafer pre-alignment device provided in an embodiment of the present invention;

[0052] Figure 7 A flowchart of another pre-alignment eccentricity calibration method based on a wafer pre-alignment device provided in an embodiment of the present invention;

[0053] Figure 8 A schematic structural diagram of a pre-alignment eccentricity calibration device provided in an embodiment of the present invention;

[0054] Fig. 9 A schematic structural diagram of a pre-alignment eccentricity calibration device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0055] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0056] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices. The orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", etc. is based on the orientation or positional relationship shown in the drawings, and is only used to illustrate the relative positional relationship between the components or components, and does not particularly limit the specific installation orientation of the components or components.

[0057] Figure 1 A schematic diagram of the structure of a wafer pre-alignment device provided by an embodiment of the present invention, referring to Figure 1 The wafer pre-alignment device in the embodiment of the present invention comprises a wafer edge distance sensor 10 and a wafer rotating table 20. The wafer edge distance sensor 10 rotates around a first actual rotation center, and the wafer rotating table 20 rotates around a second actual rotation center. The ideal rotation center and the first actual rotation center of the wafer rotating table are both located on the measurement axis of the wafer edge distance sensor. The wafer to be pre-aligned can be placed on the wafer rotating table 20, and can rotate with the wafer rotating table 20 during the process of the wafer rotating table 20 rotating around the second actual rotation center.

[0058] Figure 2 A flowchart of a pre-alignment eccentricity calibration method based on a wafer pre-alignment device is provided in an embodiment of the present invention. The pre-alignment eccentricity calibration method based on a wafer pre-alignment device in an embodiment of the present invention is applicable to situations where pre-alignment eccentricity calibration is required. The pre-alignment eccentricity calibration method based on a wafer pre-alignment device can be performed by a pre-alignment eccentricity calibration device, which can be implemented by software and / or hardware and is specifically configured in a pre-alignment eccentricity calibration device. Reference Figure 2The pre-alignment eccentricity calibration method based on the wafer pre-alignment device in the embodiment of the present invention includes:

[0059] S110, obtaining wafer fitting radius when the wafer edge distance sensor is rotated to different positions.

[0060] Exemplary, reference Figure 1 The wafer pre-alignment device in the embodiment of the present invention further includes a first rotation driving module 30 and a second rotation driving module 40. The first rotation driving module 30 can drive the wafer edge distance sensor 10 to rotate around the first actual rotation center, and the second rotation driving module 40 can drive the wafer rotating table 20 to rotate around the second actual rotation center. The pre-alignment eccentricity calibration device in the embodiment of the present invention is connected to the wafer edge distance sensor 10, the first rotation driving module 30 and the second rotation driving module 40 respectively. The wafer edge distance sensor 10 can be controlled to rotate around the first actual rotation center by controlling the first rotation driving module 30 to work. Whenever a position where the wafer fitting radius needs to be obtained is reached, the wafer edge distance sensor 10 can be controlled to stop rotating by controlling the first rotation driving module 30 to stop working, so as to fix the wafer edge distance sensor 10 to the position. After the wafer edge distance sensor 10 is fixed to the position where the wafer fitting radius needs to be obtained, the pre-alignment eccentricity calibration device will control the wafer rotating table 20 to rotate around the second actual rotation center by controlling the second rotation drive module 40 to work. At the same time, the distance information between the first actual rotation center and the wafer edge of the wafer rotating table 20 during the rotation process and the rotation angle information of the wafer rotating table 20 will be obtained through the wafer edge distance sensor 10. Finally, a circle fitting is performed based on the obtained distance information and rotation angle information to obtain the corresponding wafer fitting radius. Repeating the above operation will enable the wafer fitting radius of the wafer edge distance sensor 10 to be obtained when it is rotated to different positions.

[0061] S120 , determining a minimum wafer fitting radius according to multiple wafer fitting radii.

[0062] Exemplarily, multiple wafer fitting radiuses obtained are compared to find out the smallest wafer fitting radius.

[0063] S130 , determining an actual distance between the first actual rotation center and the second actual rotation center according to the minimum wafer fitting radius.

[0064] As a feasible implementation, determining the actual distance between the first actual rotation center and the second actual rotation center according to the minimum wafer fitting radius includes: determining the actual distance according to the minimum wafer fitting radius and the following corresponding relationship: L 1 =R+L 0 -r min , where L1 It represents the actual distance, R represents the radius of the wafer, and L 0 represents the preset distance between the first actual rotation center and the ideal rotation center, r min It represents the minimum wafer fitting radius.

[0065] Figure 3 A schematic plan view of an initial state of wafer pre-alignment provided by an embodiment of the present invention, Figure 4 A schematic diagram of a wafer pre-alignment calibration state provided by an embodiment of the present invention, wherein the straight line where the measurement axis of the wafer edge distance sensor 10 is located is the x-axis; LCCD denoted by the first actual rotation center, which is located at the midpoint of the measurement axis of the wafer edge distance sensor 10; wafer Indicates the center of the wafer; O real It represents the second actual rotation center; ideal It represents the theoretical rotation center, which is on the x-axis and is parallel to the first actual rotation center O. LCCD The distance between them is L 0 , L 0 It can be equal to the radius R of the wafer; P represents the intersection of the edge of the wafer and the measurement axis of the wafer edge distance sensor 10; ρ 0 It represents the second actual rotation center O real With the theoretical rotation center O ideal The distance between 1 Indicates the wafer center O wafer With the theoretical rotation center O ideal The distance between 0 represents the theoretical rotation center O ideal and the second actual rotation center O real The angle between the straight line and the positive x-axis; θ 1 Indicates the wafer center O wafer and the second actual rotation center O real The angle between the straight line and the positive direction of the x-axis is also the initial angle when the wafer is placed on the wafer; it is perpendicular to the x-axis and passes through the theoretical rotation center O ideal The straight line is the y-axis. t represents the wafer rotating around the second actual rotation center O with the wafer rotating stage 10 in the wafer pre-alignment calibration state. real The rotation angle can be obtained through the angle sensor; P 1 It represents the second actual rotation center O real The foot point on the x-axis; P 2 Indicates the wafer center O wafer The foot point on the x-axis; R represents the radius of the wafer.

[0066] refer to Figure 2 and Figure 3 , we can get the following formula:

[0067] |O ideal P|=|O ideal P| 1 |+|P 1 P 2 |+|P 2 P|.

[0068] |O ideal P|=|O ideal O real |×cosθ 0 =ρ 0 ×cosθ 0 .

[0069] |P 1 P 2 |=ρ 1 ×cos(t+θ 1 ).

[0070]

[0071] Combining the above four formulas, we can get:

[0072]

[0073] It can be understood that during the wafer pre-alignment process, ρ 0 and ρ 1 Usually in the sub-millimeter range, it is a small amount relative to the wafer radius. Therefore, the formula is changed to 0 =0 and ρ 1 = 0, Taylor expansion can be obtained:

[0074]

[0075] By 0 and ρ 1 The small quantities higher than the first order are usually in the micron or submicron order, which is the same order as the measured noise. Therefore, the part higher than the first order in the above formula is discarded to obtain:

[0076] |O ideal P|=ρ 0 ×cosθ 0 +ρ 1 ×cos(t+θ 1 )+R.

[0077] The multiple sets of data obtained [|O ideal P|,t] is transformed into the rectangular coordinate system:

[0078] x=|Oideal P|×cost=(ρ 0 ×cosθ 0 +ρ 1 ×cos(t+θ 1 )+R)×cost.

[0079] y=|O ideal P|×sint=(ρ 0 ×cosθ 0 +ρ 1 ×cos(t+θ 1 )+R)×sint.

[0080] Combining the above two formulas, we can get:

[0081] (x-ρ 1 ×cosθ 1 ) 2 +(y+ρ 1 ×sinθ 1 ) 2 =(R+ρ 0 ×cosθ 0 ) 2 +(ρ 1 ×sin(t+θ 1 )) 2 .

[0082] Discard the small amount (ρ 1 ×sin(t+θ 1 )) 2 The theoretical expression of the fitting circle equation of the wafer can be obtained as follows:

[0083] (x-ρ 1 ×cosθ 1 ) 2 +(y+ρ 1 ×sinθ 1 ) 2 =(R+ρ 0 ×cosθ 0 ) 2 .

[0084] The above formula is the theoretical formula for wafer fitting, where the center of the circle is (ρ 1 ×cosθ 1 ,-ρ 1 ×sinθ 1 ), the radius is (R+ρ 0 ×cosθ 0 ). Since the derived coordinates of the center of the circle are the coordinates of the wafer relative to the actual rotation center, rather than the coordinates of the origin of the established coordinate system, the origin of the coordinate system is eccentric to the actual rotation center [ρ 0,θ 0 ], these two numbers are unknown, so the eccentricity [ρ 0 ,θ 0 ] will cause errors in wafer positioning.

[0085] From the theoretical formula of wafer fitting above, it can be seen that when θ x =0, that is, the measuring axis of the wafer edge distance sensor 10 rotates to the second actual rotation center O real When collinear, the obtained wafer fitting radius is the smallest.

[0086] Figure 5 for Figure 3 and Figure 4 A simplified diagram of the wafer pre-alignment plane diagram provided, where L 1 It represents the first actual rotation center O LCCD and the second actual rotation center O real The actual distance between x It represents the second actual rotation center O real and the first actual rotation center O LCCD The angle between the straight line and the positive direction of the x-axis is, as can be understood, the distance sensor 10 around the first actual rotation center O at the edge of the wafer. LCCD During the rotation, θ x will change, satisfying -90°<θ x <90°, reference Figure 5 , we can get the following formula:

[0087] ρ 0 ×cosθ 0 =L 0 -L 1 ×cosθ x .

[0088] Due to L 0 With L 1 is a constant, so (L 0 -L 1 ×cosθ x ) will be First it decreases and then increases. When θ x =0, that is, the measuring axis of the wafer edge distance sensor 10 rotates to the second actual rotation center O real When collinear, (ρ 0 ×cosθ 0 ) has a minimum value (L 0 -L 1 ), combined with the above theoretical formula of wafer fitting, the following corresponding relationship can be obtained:

[0089] r min =R+ρ0 ×cosθ 0 =R+L 0 -L 1 .

[0090] Therefore, the r obtained in step S120 can be min Substitute into the formula: L 1 =R+L 0 -r min To determine the actual distance L between the first actual rotation center and the second actual rotation center 1 .

[0091] S140, controlling the wafer edge distance sensor to be fixed at the wafer edge distance sensor position corresponding to the minimum wafer fitting radius, so that the second actual rotation center is located on the measurement axis.

[0092] Exemplarily, the theoretical formula fitted from the above wafer is: (x-ρ 1 ×cosθ 1 ) 2 +(y+ρ 1 ×sinθ 1 ) 2 =(R+ρ 0 ×cosθ 0 ) 2 , we can see that when θ x =0, that is, the measuring axis of the wafer edge distance sensor 10 rotates to the second actual rotation center O real When the wafers are collinear, the obtained wafer fitting radius is the smallest. Therefore, by fixing the wafer edge distance sensor at the wafer edge distance sensor position corresponding to the smallest wafer fitting radius, the second actual rotation center can be located on the measurement axis.

[0093] S150, controlling the second actual rotation center to coincide with the ideal rotation center according to the actual distance.

[0094] In a feasible implementation manner, by setting the preset distance L between the first actual rotation center and the ideal rotation center 0 Replace with L 1 The value of the second actual rotation center O real With the ideal rotation center O ideal Overlapping, thereby eliminating the influence of eccentricity on wafer positioning during the pre-alignment process.

[0095] The embodiment of the present invention fixes the wafer edge distance sensor 10 at a position corresponding to the minimum wafer fitting radius during its rotation around the first rotation center, and controls the second actual rotation center of the wafer rotating table 20 to coincide with its ideal rotation center according to the actual distance between the first actual rotation center and the second actual rotation center obtained, so that the second actual rotation center of the wafer rotating table 20 is located on the measuring axis of the wafer edge distance sensor and coincides with the ideal rotation center, thereby solving the problem in the existing wafer pre-alignment process that due to the installation error of the wafer edge distance sensor 10 and the wafer rotating table 20, the straight line where the measuring axis of the wafer edge distance sensor 10 is located is not colinear with the second actual rotation center of the wafer rotating table 20, and the second actual rotation center of the wafer rotating table 20 does not coincide with the theoretical rotation center located on the measuring axis of the wafer edge distance sensor 10, thereby resulting in a decrease in the accuracy of wafer pre-alignment, which is beneficial to improving the accuracy of wafer pre-alignment.

[0096] Figure 6 A flowchart of another pre-alignment eccentricity calibration method based on a wafer pre-alignment device provided in an embodiment of the present invention, Figure 6 The embodiment shown in the figure describes in detail how to obtain the wafer fitting radius when the wafer edge distance sensor is rotated to different positions, refer to Figure 6 The pre-alignment eccentricity calibration method based on the wafer pre-alignment device in the embodiment of the present invention includes:

[0097] S210 , obtaining the i-th wafer fitting radius of the wafer edge distance sensor at the i-th position, where i≥1.

[0098] As a feasible implementation method, the i-th wafer fitting radius of the wafer edge distance sensor at the i-th position is obtained, including: when the wafer edge distance sensor is at the i-th position, controlling the wafer turntable to rotate at least one circle; obtaining the i-th distance information between the wafer edge and the ideal rotation center and the i-th rotation angle information of the wafer turntable during the rotation of the wafer turntable; and determining the i-th wafer fitting radius according to the i-th distance information and the i-th rotation angle information.

[0099] Specifically, determining the i-th wafer fitting radius according to the i-th distance information and the i-th rotation angle information includes: fitting an i-th fitting circle according to the i-th distance information and the i-th rotation angle information, the radius of the i-th fitting circle being the i-th wafer fitting radius.

[0100] It should be noted that when obtaining the i-th distance information between the first actual rotation center and the second actual rotation center, the pre-alignment eccentricity calibration device in the embodiment of the present invention first obtains the distance between the first actual rotation center and the wafer edge through the wafer edge distance sensor 10, and then adds the obtained distance between the first actual rotation center and the wafer edge to the preset distance between the first actual rotation center and the ideal rotation center to obtain the distance between the wafer edge and the ideal rotation center.

[0101] S220, control the wafer edge distance sensor to rotate along the i-th rotation direction by the i-th preset angle to the (i+1)-th position, and obtain the (i+1)-th wafer fitting radius of the wafer edge distance sensor at the (i+1)-th position, wherein the i-th rotation direction includes a clockwise direction or a counterclockwise direction.

[0102] It should be noted that the first rotation direction and the first preset angle are set by those skilled in the art.

[0103] S230. Determine the (i+1)th rotation direction and the (i+1)th rotation angle of the wafer edge distance sensor according to the size relationship between the i-th wafer fitting radius and the (i+1)-th wafer fitting radius, wherein the (i+1)-th rotation direction includes a clockwise direction or a counterclockwise direction.

[0104] As a feasible implementation manner, determining the (i+1)th rotation direction and the (i+1)th rotation angle of the wafer edge distance sensor according to the size relationship between the i-th wafer fitting radius and the (i+1)-th wafer fitting radius includes:

[0105] If the i-th wafer fitting radius is smaller than the (i+1)-th wafer fitting radius, it is determined that the (i+1)-th rotation direction is the same as the i-th rotation direction, and the (i+1)-th rotation angle is the same as the i-th preset angle.

[0106] If the i-th wafer fitting radius is greater than the (i+1)-th wafer fitting radius, it is determined that the (i+1)-th rotation direction is opposite to the i-th rotation direction, and the (i+1)-th rotation angle is the same as the i-th preset angle.

[0107] If the i-th wafer fitting radius is equal to the (i+1)-th wafer fitting radius, it is determined that the (i+1)-th rotation direction is opposite to the i-th rotation direction, and the (i+1)-th rotation angle is less than the i-th preset angle.

[0108] S240, control the wafer edge distance sensor to rotate along the (i+1)th rotation direction by the (i+1)th preset angle to the (i+2)th position, and obtain the (i+2)th wafer fitting radius of the wafer edge distance sensor at the (i+2)th position.

[0109] S250 , determining a minimum wafer fitting radius according to multiple wafer fitting radii.

[0110] S260 , determining an actual distance between the first actual rotation center and the second actual rotation center according to the minimum wafer fitting radius.

[0111] S270, controlling the wafer edge distance sensor to be fixed at the wafer edge distance sensor position corresponding to the minimum wafer fitting radius, so that the second actual rotation center is located on the measurement axis.

[0112] S280: Control the second actual rotation center to coincide with the ideal rotation center according to the actual distance.

[0113] Figure 7 A flowchart of another pre-alignment eccentricity calibration method based on a wafer pre-alignment device provided in an embodiment of the present invention, Figure 7 The embodiment shown in the figure describes in detail how to control the second actual rotation center to coincide with the ideal rotation center according to the actual distance. Figure 7 The pre-alignment eccentricity calibration method based on the wafer pre-alignment device in the embodiment of the present invention includes:

[0114] S310, obtaining wafer fitting radius when the wafer edge distance sensor is rotated to different positions.

[0115] S320 , determining a minimum wafer fitting radius according to multiple wafer fitting radii.

[0116] S330 , determining an actual distance between the first actual rotation center and the second actual rotation center according to the minimum wafer fitting radius.

[0117] S340, controlling the wafer edge distance sensor to be fixed at the wafer edge distance sensor position corresponding to the minimum wafer fitting radius, so that the second actual rotation center is located on the measurement axis;

[0118] S350, determining a moving direction and a moving distance of the wafer rotation stage according to the actual distance and a preset distance between the first actual rotation center and the ideal rotation center.

[0119] Exemplarily, the distance between the second actual rotation center and the ideal rotation center may be determined according to the following corresponding relationship: L 3 =L 0 -L 1 =r min -R, where L 1 It represents the actual distance between the first actual rotation center and the second actual rotation center, R represents the radius of the wafer, L 0 represents the preset distance between the first actual rotation center and the ideal rotation center, r minIt indicates the minimum wafer fitting radius. The moving direction of the wafer rotating table is the direction from the first actual rotation center to the ideal rotation center, that is, Figure 3 , Figure 4 and Figure 5 In the x-axis direction shown, the moving distance of the wafer rotating stage along the moving direction is the distance L between the second actual rotation center and the ideal rotation center. 3 .

[0120] S360, controlling the movement of the wafer stage according to the moving direction and the moving distance so that the second actual rotation center coincides with the ideal rotation center.

[0121] Exemplary, reference Figure 1 The pre-alignment device in the embodiment of the present invention further includes a first direction moving driving module 50, a second direction moving driving module 60 and a third direction moving driving module 70. The first direction moving driving module 50 is used to drive the wafer rotating table 20 to move along the first direction. Figure 3 , Figure 4 and Figure 5 The x-axis shown in the figure moves in a straight line, and the second direction movement driving module 60 is used to drive the wafer rotating table 20 along the x-axis as shown in the figure. Figure 3 , Figure 4 and Figure 5 The third direction moving driving module 70 is used to drive the wafer rotating table 20 along the straight line as shown in FIG. Figure 3 , Figure 4 and Figure 5 The x-axis and y-axis shown are both perpendicular to the z-axis (not shown in the figure) and move in a straight line.

[0122] The pre-alignment eccentricity calibration device in the embodiment of the present invention is connected to the first direction movement driving module 50, the second direction movement driving module 60 and the third direction movement driving module 70 respectively. The pre-alignment eccentricity calibration device can control the wafer stage according to the moving direction and moving distance of the wafer rotating table determined in step S350. Figure 3 , Figure 4 and Figure 5 The x-axis moves in the opposite direction by a distance L 3 The second actual rotation center can be made to coincide with the ideal rotation center.

[0123] Based on the same inventive concept, an embodiment of the present invention further provides a pre-alignment eccentricity calibration device, Figure 8 A schematic diagram of the structure of a pre-alignment eccentricity calibration device provided in an embodiment of the present invention, referring to Figure 8 , the pre-alignment eccentricity calibration device in the embodiment of the present invention comprises:

[0124] The wafer fitting radius acquisition unit 410 is used to acquire the wafer fitting radius when the wafer edge distance sensor is rotated to different positions.

[0125] The minimum wafer fitting radius determining unit 420 is used to determine the minimum wafer fitting radius according to multiple wafer fitting radiuses.

[0126] The actual distance determining unit 430 is used to determine the actual distance between the first actual rotation center and the second actual rotation center according to the minimum wafer fitting radius.

[0127] The wafer edge distance sensor calibration unit 440 is used to control the wafer edge distance sensor to be fixed at the wafer edge distance sensor position corresponding to the minimum wafer fitting radius, so that the second actual rotation center is located on the measurement axis.

[0128] The rotation center calibration unit 450 is used to control the second actual rotation center to coincide with the ideal rotation center according to the actual distance.

[0129] The pre-alignment eccentricity calibration device provided in the embodiment of the present invention can execute the pre-alignment eccentricity calibration method provided in any embodiment of the present invention, and has the corresponding functional modules and beneficial effects of the execution method.

[0130] Fig. 9 A schematic diagram of a pre-alignment eccentricity calibration device 500 that can be used to implement an embodiment of the present invention is shown, and the pre-alignment eccentricity calibration device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workbenches, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The pre-alignment eccentricity calibration device can also represent various forms of mobile devices, such as personal digital processing, cellular phones, smart phones, wearable devices (such as helmets, glasses, watches, etc.) and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present invention described and / or required herein.

[0131] like Fig. 9As shown, the pre-alignment eccentricity calibration device 500 includes at least one processor 510, and a memory connected to the at least one processor 510 in communication, such as a read-only memory (ROM) 520, a random access memory (RAM) 530, etc., wherein the memory stores a computer program that can be executed by at least one processor, and the processor 510 can perform various appropriate actions and processes according to the computer program stored in the read-only memory (ROM) 520 or the computer program loaded from the storage unit 580 to the random access memory (RAM) 530. In the RAM 530, various programs and data required for the operation of the pre-alignment eccentricity calibration device 500 can also be stored. The processor 510, the ROM 520, and the RAM 530 are connected to each other through a bus 540. An input / output (I / O) interface 550 is also connected to the bus 540.

[0132] Multiple components in the pre-alignment eccentricity calibration device 500 are connected to the I / O interface 550, including: an input unit 560, such as a keyboard, a mouse, etc.; an output unit 570, such as various types of displays, speakers, etc.; a storage unit 580, such as a disk, an optical disk, etc.; and a communication unit 590, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 590 allows the pre-alignment eccentricity calibration device 500 to exchange information / data with other devices through a computer network such as the Internet and / or various telecommunication networks.

[0133] The processor 510 may be a variety of general and / or special processing components with processing and computing capabilities. Some examples of the processor 510 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various dedicated artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any appropriate processor, controller, microcontroller, etc. The processor 510 performs the various methods and processes described above, such as a pre-alignment eccentricity calibration method.

[0134] In some embodiments, the pre-alignment eccentricity calibration method may be implemented as a computer program, which is tangibly contained in a computer-readable storage medium, such as a storage unit 580. In some embodiments, part or all of the computer program may be loaded and / or installed on the pre-alignment eccentricity calibration device 500 via the ROM 520 and / or the communication unit 590. When the computer program is loaded into the RAM 530 and executed by the processor 510, one or more steps of the pre-alignment eccentricity calibration method described above may be performed. Alternatively, in other embodiments, the processor 510 may be configured to perform the pre-alignment eccentricity calibration method in any other suitable manner (e.g., by means of firmware).

[0135] Various implementations of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), systems on chips (SOCs), load programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various implementations can include: being implemented in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which can be a special purpose or general purpose programmable processor that can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device.

[0136] Computer programs for implementing the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that when the computer program is executed by the processor, the functions / operations specified in the flow chart and / or block diagram are implemented. The computer program may be executed entirely on the machine, partially on the machine, partially on the machine and partially on a remote machine as a stand-alone software package, or entirely on a remote machine or server.

[0137] In the context of the present invention, a computer-readable storage medium may be a tangible medium that may contain or store a computer program for use by or in combination with an instruction execution system, device or equipment. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices or equipment, or any suitable combination of the foregoing. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. A more specific example of a machine-readable storage medium may include an electrical connection based on one or more lines, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0138] To provide interaction with a user, the systems and techniques described herein may be implemented on a pre-alignment decentering calibration device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to a user; and a keyboard and a pointing device (e.g., a mouse or trackball) through which a user can provide input to the pre-alignment decentering calibration device. Other types of devices may also be used to provide interaction with a user; for example, the feedback provided to the user may be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user may be received in any form (including acoustic input, voice input, or tactile input).

[0139] The systems and techniques described herein may be implemented in a computing system that includes backend components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes frontend components (e.g., a user computer with a graphical user interface or a web browser through which a user can interact with implementations of the systems and techniques described herein), or a computing system that includes any combination of such backend components, middleware components, or frontend components. The components of the system may be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: a local area network (LAN), a wide area network (WAN), a blockchain network, and the Internet.

[0140] A computing system may include a client and a server. The client and the server are generally remote from each other and usually interact through a communication network. The client and server relationship is generated by computer programs running on the corresponding computers and having a client-server relationship with each other. The server may be a cloud server, also known as a cloud computing server or cloud host, which is a host product in the cloud computing service system to solve the defects of difficult management and weak business scalability in traditional physical hosts and VPS services.

[0141] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0142] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

[0143] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A pre-alignment eccentricity calibration method based on a wafer pre-alignment device, wherein the wafer pre-alignment device comprises a wafer edge distance sensor and a wafer rotating table, wherein the wafer edge distance sensor rotates around a first actual rotation center, and the wafer rotating table rotates around a second actual rotation center, and the ideal rotation center of the wafer rotating table and the first actual rotation center are both located on the measurement axis of the wafer edge distance sensor, characterized in that: The pre-alignment eccentricity calibration method comprises: Obtaining the wafer fitting radius when the wafer edge distance sensor is rotated to different positions; Determining a minimum wafer fitting radius according to the plurality of wafer fitting radiuses; Determine an actual distance between the first actual rotation center and the second actual rotation center according to the minimum wafer fitting radius; Controlling the wafer edge distance sensor to be fixed at a wafer edge distance sensor position corresponding to the minimum wafer fitting radius, so that the second actual rotation center is located on the measurement axis; The second actual rotation center is controlled to coincide with the ideal rotation center according to the actual distance.

2. The pre-alignment eccentricity calibration method according to claim 1, characterized in that: Obtain the wafer fitting radius when the wafer edge distance sensor is rotated to different positions, including: Obtaining an i-th wafer fitting radius of the wafer edge distance sensor at an i-th position, where i≥1; Controlling the wafer edge distance sensor to rotate along the i-th rotation direction by the i-th preset angle to the (i+1)-th position, and obtaining the (i+1)-th wafer fitting radius of the wafer edge distance sensor at the (i+1)-th position; the i-th rotation direction includes a clockwise direction or a counterclockwise direction; Determining the (i+1)th rotation direction and the (i+1)th rotation angle of the wafer edge distance sensor according to the magnitude relationship between the i-th wafer fitting radius and the (i+1)-th wafer fitting radius; the (i+1)-th rotation direction includes a clockwise direction or a counterclockwise direction; The wafer edge distance sensor is controlled to rotate along the (i+1)th rotation direction by the (i+1)th preset angle to the (i+2)th position, and the (i+2)th wafer fitting radius of the wafer edge distance sensor at the (i+2)th position is obtained.

3. The pre-alignment eccentricity calibration method according to claim 2, characterized in that: Obtaining the i-th wafer fitting radius of the wafer edge distance sensor at the i-th position, comprising: When the wafer edge distance sensor is at the i-th position, controlling the wafer rotating table to rotate at least one circle; Acquiring i-th distance information between the edge of the wafer and the ideal rotation center and i-th rotation angle information of the wafer rotation table during the rotation of the wafer rotation table; The i-th wafer fitting radius is determined according to the i-th distance information and the i-th rotation angle information.

4. The pre-alignment eccentricity calibration method according to claim 3, characterized in that: Determining the i-th wafer fitting radius according to the i-th distance information and the i-th rotation angle information includes: An i-th fitting circle is fitted according to the i-th distance information and the i-th rotation angle information, and the radius of the i-th fitting circle is the i-th wafer fitting radius.

5. The pre-alignment eccentricity calibration method according to claim 2, characterized in that: Determining the (i+1)th rotation direction and the (i+1)th rotation angle of the wafer edge distance sensor according to the magnitude relationship between the i-th wafer fitting radius and the (i+1)-th wafer fitting radius includes: If the i-th wafer fitting radius is smaller than the (i+1)-th wafer fitting radius, it is determined that the (i+1)-th rotation direction is the same as the i-th rotation direction, and the (i+1)-th rotation angle is the same as the i-th preset angle; If the i-th wafer fitting radius is greater than the (i+1)-th wafer fitting radius, it is determined that the (i+1)-th rotation direction is opposite to the i-th rotation direction, and the (i+1)-th rotation angle is the same as the i-th preset angle; If the i-th wafer fitting radius is equal to the (i+1)-th wafer fitting radius, it is determined that the (i+1)-th rotation direction is opposite to the i-th rotation direction, and the (i+1)-th rotation angle is less than the i-th preset angle.

6. The pre-alignment eccentricity calibration method according to claim 1, characterized in that: Determining an actual distance between the first actual rotation center and the second actual rotation center according to the minimum wafer fitting radius includes: The actual distance is determined according to the minimum wafer fitting radius and the following corresponding relationship: L1=R+L0-r min ; L1 represents the actual distance, R represents the radius of the wafer, L0 represents the preset distance between the first actual rotation center and the ideal rotation center, and r min It represents the minimum wafer fitting radius.

7. The pre-alignment eccentricity calibration method according to claim 1, characterized in that: Controlling the second actual rotation center to coincide with the ideal rotation center according to the actual distance includes: Determining a moving direction and a moving distance of the wafer rotation stage according to the actual distance and a preset distance between the first actual rotation center and the ideal rotation center; The movement of the wafer stage is controlled according to the moving direction and the moving distance.

8. A pre-alignment eccentricity calibration device, used to perform the pre-alignment eccentricity calibration method as claimed in any one of claims 1 to 7, characterized in that: The pre-alignment eccentricity calibration device comprises: A wafer fitting radius acquisition unit is used to acquire the wafer fitting radius when the wafer edge distance sensor is rotated to different positions; A minimum wafer fitting radius determining unit, used to determine a minimum wafer fitting radius according to a plurality of the wafer fitting radii; an actual distance determining unit, configured to determine an actual distance between the first actual rotation center and the second actual rotation center according to the minimum wafer fitting radius; a wafer edge distance sensor calibration unit, used for controlling the wafer edge distance sensor to be fixed at a wafer edge distance sensor position corresponding to the minimum wafer fitting radius so that the second actual rotation center is located on the measurement axis; A rotation center calibration unit is used to control the second actual rotation center to coincide with the ideal rotation center according to the actual distance.

9. A pre-alignment eccentricity calibration device, characterized in that: The pre-alignment eccentricity calibration device comprises: one or more processors; A storage device for storing one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement the pre-alignment eccentricity calibration method as described in any one of claims 1-7.

10. A storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the pre-alignment eccentricity calibration method as described in any one of claims 1 to 7 is implemented.

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