TW202018251A - Grid error measurement method and measurement device, and optical equipment - Google Patents

Abstract

A grid error measurement method and a measurement device, and optical equipment. The grid error measurement method comprises: acquiring first actual position information about a preset alignment measurement mark on a substrate by means of a position measurement system in optical equipment, the substrate being horizontally adsorbed on a substrate adsorbing table of the optical equipment at a first angle, and a first direction being perpendicular to the second direction; acquiring second actual position information about the preset alignment measurement mark by means of the position measurement system, the substrate being horizontally absorbed on the substrate adsorbing table at a second angle, and the second angle being different from the first angle; and calculating the grid error of the position measurement system according to the first actual position information, the second actual position information, and the standard position information of the preset alignment measurement mark.

Description

Measuring method, measuring device and optical equipment for grid error

Embodiments of the present invention relate to position measurement technology, for example, to a grid error measurement method, measurement device, and optical equipment.

The precise motion equipment in the position measuring equipment or exposure machine will be equipped with interferometer or grating ruler measuring system on each measuring axis for positioning control and measurement of the motion table. However, there are measurement errors in the position measurement system itself, which may cause deviations between the actual position and the ideal position of the sports table, resulting in inaccurate measurement.

Generally, grid error (the deviation of the actual deformation of a certain point horizontally from its ideal position, connecting these points to form a spatially arranged checkerboard grid) is used to characterize the horizontal error of the position measurement system. The grid error needs to be compensated or calibrated using certain methods and methods to make the final position measurement or movement position accurate.

At present, most of the position measurement equipment on the market uses large masks or reference plates for grid correction. However, it is inconvenient to use and maintain the calibration. It is necessary to manually upload the mask at different positions on the sports table to calibrate the local errors one by one. , And the photomask also needs to be maintained separately; the second is as the industry develops In particular, the size of substrates in the field of flat panel displays is also increasing. The size of subsequent photomasks needs to be increased synchronously, which will inevitably increase the cost and have limitations. Another grid calibration scheme uses the position model of the position measurement system (interferometer, grating ruler), which needs to collect a large range of position data of the motion table in different postures (including rotation, tilt, etc.) for mathematical fitting calculation. The motion stage of most position measuring equipment can generally only set up a single degree of freedom of movement. Correlation data of multiple degrees of freedom cannot be obtained, which makes the position model unable to be solved. Therefore, the grid error cannot be calculated and calibrated.

The following is an overview of the topics described in detail in this specification. This summary is not intended to limit the scope of protection of patent applications.

The invention provides a grid error measuring method, a measuring device and an optical device. The grid error is calculated and the measurement position of the position measurement system is calibrated to make the final position measurement or movement position accurate.

In a first aspect, an embodiment of the present invention provides a method for measuring grid errors, characterized in that it includes: acquiring the first actual position information of a preset alignment measurement mark on a substrate by a position measurement system in an optical device, wherein , A plurality of alignment measurement marks arranged in an array along the first direction and the second direction are formed on the substrate to form a measurement grid, and the substrate is horizontally adsorbed on the substrate adsorption table of the optical device at a first angle, The first direction and the second direction are perpendicular; the second actual position information of the preset alignment measurement mark is acquired by the position measurement system, wherein the substrate is horizontally adsorbed on the substrate adsorption table at a second angle The second angle is different from the first angle; the grid error of the position measurement system is calculated based on the first actual position information, the second actual position information, and the standard position information of the preset alignment measurement mark.

In a second aspect, an embodiment of the present invention further provides a grid error measurement device, characterized in that it includes: a first actual position information module configured to obtain a preset alignment on a substrate by a position measurement system in an optical device The first actual position information of the measurement mark, wherein the substrate is provided with a plurality of alignment measurement marks arranged in an array along the first direction and the second direction to form a measurement grid, and the substrate is horizontal at a first angle Adsorbed on the substrate adsorption table of the optical device, the first direction and the second direction are perpendicular; the second actual position information acquisition module is set to acquire the preset alignment measurement mark by the position measurement system Second actual position information, wherein the substrate is horizontally adsorbed on the substrate adsorption table at a second angle, the second angle is different from the first angle; the grid error calculation module is set to be based on the first actual position information 2. The second actual position information and the standard position information of the preset alignment measurement mark calculate the grid error of the position measurement system.

In a third aspect, an embodiment of the present invention further provides an optical device, characterized in that it includes the grid error measuring device described in the second aspect above.

You can understand other aspects after reading and understanding the drawings and detailed description.

The invention provides a grid error measuring method, a measuring device and an optical device. The grid error is calculated and the measurement position of the position measurement system is calibrated to make the final position measurement or movement position accurate.

1‧‧‧ Whole machine gas bath constant temperature control system

2‧‧‧Full machine protection frame

3‧‧‧Optical measuring stage

4‧‧‧Optical measuring stage motion guide

5‧‧‧rail bracket

6‧‧‧X interferometer measuring system

7‧‧‧Coarse position sensor

8‧‧‧Position precise measurement and graphic rough measurement sensor

9‧‧‧Precision position measurement and graphic precision measurement sensor

10‧‧‧The first height measurement sensor

11‧‧‧Second height measurement sensor

12‧‧‧ Base stage

13‧‧‧Base adsorption table

14‧‧‧ Base rail motion guide

15‧‧‧Y interferometer measuring system

16‧‧‧Marble support table

17‧‧‧Shock absorption system

100‧‧‧ base

200‧‧‧Alignment measurement mark

201‧‧‧ Actual position

202‧‧‧ Standard position

301‧‧‧ Actual position of carrier

302‧‧‧ Expected position of carrier

Rz‧‧‧rotation

Fig. 1 is a schematic structural diagram of a position measuring device provided by an embodiment of the present invention.

Fig. 2 is a flow chart of a method for measuring grid error provided by an embodiment of the present invention.

[Figure 3] is a schematic diagram of a substrate structure provided by an embodiment of the present invention.

FIG. 4 is a graph structure of several alignment measurement marks provided by an embodiment of the present invention.

FIG. 5 is a schematic diagram of a rotation error provided by an embodiment of the present invention.

Fig. 6 is a schematic diagram of a non-orthogonal error provided by an embodiment of the present invention.

7 is a schematic diagram of a translation error provided by an embodiment of the present invention.

FIG. 8 is a flowchart of another method for measuring grid errors provided by an embodiment of the present invention.

9 is a schematic diagram of a rotation error provided by an embodiment of the present invention.

FIG. 10 is a flowchart of another method for measuring grid errors provided by an embodiment of the present invention.

Fig. 11 is a schematic diagram of a non-orthogonal error provided by an embodiment of the present invention.

FIG. 12 is a flowchart of another method for measuring grid errors provided by an embodiment of the present invention.

[Fig. 13] is a schematic diagram of a translation error provided by an embodiment of the present invention.

FIG. 14 is a structural block diagram of a grid error measurement device provided by an embodiment of the present invention.

The present invention will be further described in detail below with reference to the drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should be further noted that, in order to facilitate description, the drawings only show parts, but not all structures related to the present invention.

FIG. 1 is a schematic structural diagram of a position measurement device according to an embodiment of the present invention. It should be noted that the position measuring device in FIG. 1 is only a specific example provided by this embodiment, and does not limit the present invention.

Referring to FIG. 1, the position measuring device may include: a complete gas bath constant temperature control system 1, It includes a temperature measurement sensor and a temperature control gas bath unit to ensure the stability of the internal environment of the whole machine; the protective frame 2 of the whole machine is used to provide protection and thermal insulation functions; the optical measurement stage 3 is used to carry optical measurement sensors It also performs horizontal X-direction and vertical Z-motion control. Among them, the optical measurement stage 3 is equipped with a position coarse measurement sensor 7, a position precise measurement and graphic coarse measurement sensor 8, a position precise measurement and graphic precision The measurement sensor 9, the first height measurement sensor 10 is installed on the position precision measurement and graphic rough measurement sensor 8, and the second height measurement sensor 11 is installed on the position precision measurement and graphic measurement sensor 9 ; Optical measurement stage motion guide rail 4 and guide rail bracket 5; X-direction interferometer measurement system 6, used to measure the optical measurement stage motion position; substrate stage 12, used to carry the measurement substrate, and horizontal Y-direction motion control; Substrate adsorption table 13 for adsorbing the measurement substrate, with a substrate constant temperature cooling system; substrate carrier movement guide 14; Y-directional interferometer measurement system 15 for measuring the substrate carrier movement position; marble support table 16, for Supports the base stage and weakens the motion impulse of the base stage during the measurement process; the shock absorption system 17 is used to provide the vibration elimination effect of the stage movement during the measurement process.

It can be understood that, considering the subsequent needs, the substrate needs to be horizontally adsorbed on the substrate adsorption table 13 at different angles (for example, 0 degrees, 90 degrees, and 180 degrees). For the convenience of measurement, the substrate 100 may be round or square, for example Sexually, it can be cut by a microtome. When the substrate 100 is square, the side length can be set to be shorter than or equal to the short side of the substrate stage 12 to ensure that the substrate 100 is within the range of the substrate stage 12.

2 is a flowchart of a grid error measurement method provided by an embodiment of the present invention. This method is suitable for professional measurement equipment that requires position measurement calibration, such as the position measurement equipment described above. Referring to FIG. 2, a method for measuring grid errors according to Embodiment 1 of the present invention includes steps S110 to S130.

In step S110, the position measurement system in the optical device The first actual position information of the alignment measurement mark is provided, wherein the base is provided with a plurality of alignment measurement marks arranged in an array along the first direction and the second direction to form a measurement grid, and the base is at a first angle It is horizontally adsorbed on the substrate adsorption table of the optical device, and the first direction and the second direction are perpendicular.

The optical device may be a lithography machine, an exposure machine, or other professional measurement equipment that requires position measurement and calibration. The position measurement system in the optical equipment can perform positioning control and measurement on the motion table.

The specific structure of the position measurement system is not limited in the present invention. In an embodiment, the position measurement system is an interferometer measurement system, a laser triangle ruler, or a laser displacement sensor. The position measuring system can also be other structures, such as precision motion equipment in the exposure machine.

Continuing to refer to FIG. 1, the movement direction of the optical measurement stage frame in the position measurement system can be defined as the X direction, the direction perpendicular to the X direction on the horizontal plane is the Y direction, and the vertical direction is the Z direction, to establish an XYZ three-dimensional coordinate system.

In an embodiment, the first direction is parallel to the X axis in the preset coordinate system, and the second direction is parallel to the Y axis in the preset coordinate system; or, the first direction is parallel to the Y axis in the preset coordinate system , The second direction is parallel to the X axis in the aforementioned preset coordinate system.

3 is a schematic diagram of a substrate structure provided by an embodiment of the present invention. Referring to FIG. 3, a plurality of alignment measurement marks 200 arranged in an array along the first direction and the second direction may be provided on the substrate 100 to form a measurement grid. Wherein, the spacing between the alignment measurement marks 200 arranged in the first direction (or the second direction) is the same, but the spacing between the alignment measurement marks 200 arranged in the first direction is the same as that along the first The distance between the alignment measurement marks 200 arranged in two directions is different.

In order to measure accurately, to avoid the measurement error caused by the graphic shape of the alignment measurement mark 200 when the substrate is adsorbed on the substrate adsorption table 13 at different angles, in one embodiment, the alignment measurement The figure marked 200 is a center symmetric figure.

It should be noted that the alignment measurement marks 200 are arranged in an array along the first direction and the second direction, and the spacing between the multiple alignment measurement marks 200 arranged along the first direction or the second direction may be the same. Can be different. The spacing between the alignment measurement marks 200 can be set according to the actual situation. In one embodiment, the spacing can be set at about 4-8 mm. The present invention does not limit the arrangement position of the alignment measurement marks 200 along the first direction and the second direction. For example, each alignment measurement mark 200 may be arranged to be rotationally symmetrically distributed with the center of the substrate 100 in the center.

4 is a graph structure of several alignment measurement marks provided by an embodiment of the present invention. Referring to FIG. 4, it can be set that the alignment measurement marks 200 themselves are rotationally symmetrically distributed at 180 degree and 90 degree centers. The alignment measurement mark 200 can be produced by exposure of the exposure machine.

Taking the position measuring device provided in FIG. 1 as an optical device as an example, the substrate 100 is set to be horizontally adsorbed on the substrate adsorption table 13 of the optical device at a first angle, and the preset alignment amount on the substrate is obtained by the position measuring system in the optical device Measure the first actual position information of the mark.

In step S120, the second actual position information of the preset alignment measurement mark is acquired by the position measurement system, wherein the substrate is horizontally adsorbed on the substrate adsorption table at a second angle, and the second angle is different from the first angle.

Considering that the motion stage of most position measuring devices can generally only set a single degree of freedom of movement, correlation data of multiple degrees of freedom cannot be obtained. Therefore, in this embodiment, only the substrate needs to be adsorbed on the substrate at different angles in the horizontal direction It can be simply placed on the adsorption table, with simple operation and low requirements on the freedom of position measuring equipment. It is suitable for the measurement of grid errors of various position measuring equipment.

In step S130, the grid error of the position measurement system is calculated according to the first actual position information, the second actual position information, and the standard position information of the preset alignment measurement mark.

Among them, the grid error is the measurement error caused by the position measurement system itself, therefore, the standard position information of the alignment measurement mark can be recorded in advance, where only the preset alignment measurement mark used in the process of calculating the grid error can be recorded It can also record the standard position information of all the alignment measurement marks set on the substrate.

It should be noted that the grid error characterizes the horizontal error of the position measurement system. Considering that most of the position measurement system's motion table can only set a single degree of freedom of movement, in order to avoid collecting correlation data of multiple degrees of freedom In the present invention, the substrate is set to be horizontally adsorbed on the substrate adsorption table at different angles, and the actual position information of the alignment measurement marks at different adsorption angles is collected, and the actual position information at different angles is calculated by a preset algorithm to obtain the position The grid error of the measurement system.

The grid error measurement method provided in this embodiment does not require a large mask, and the calculation method is simple. The measurement position of the position measurement system can be calibrated to make the final position measurement or the movement position accurate, and there is no need to collect the movement table in different Mathematical fitting calculations are performed on a large range of position data under attitude (including rotation, tilt, etc.) to avoid the situation that the correlation model of multiple degrees of freedom cannot be obtained and the position model cannot be solved.

At present, there are three main grid errors: rotation error, non-orthogonality error and translation error.

First, the rotation error is caused by the installation error of the position measurement system (for example, the interferometer measurement system), which may have an impact on the position measurement or motion positioning. The rotation error is that the optical measurement stage has a certain offset in this direction during the movement in the first direction (or the second direction), and the value of this offset changes linearly.

FIG. 5 is a schematic diagram of a rotation error provided by an embodiment of the present invention. Referring to FIG. 5, exemplarily, when the stage (optical measurement stage or substrate stage) is moving in the Y direction, the stage The rotation amount Rz of the actual position 301 of the stage relative to the desired position 302 of the stage at the same Y position changes linearly, which causes the actual position 201 of the alignment measurement mark 200 to change linearly in the Y direction relative to its standard position 202 Offset dy, this is the Y-axis rotation error of the moving table grid. Similarly, when the optical measurement stage is moving in the X direction, the rotation error will cause the position measurement or movement to be positioned relative to the standard position 202 of each alignment measurement mark 200. The offset dx in the X direction changes linearly s position.

Secondly, the non-orthogonal error is caused by the guide rail of the moving table is not vertical, which will affect the position measurement. The non-orthogonality error is that the optical measurement stage has a certain offset in another direction during the movement in the first direction (or the second direction), and the value of the offset changes linearly.

6 is a schematic diagram of a non-orthogonal error provided by an embodiment of the present invention. Referring to FIG. 6, exemplarily, when the stage is moving in the Y direction, the actual position 201 of the alignment measurement mark 200 has a linearly varying offset dx in the X direction relative to its standard position 202, this It is the Y-direction non-orthogonality error of the moving table grid. Similarly, when the optical measurement stage is moving in the X direction, the non-orthogonal error in the X direction will cause the position measurement or movement to be offset from the standard position 202 of each alignment measurement mark 200 in the Y direction The position where dy changes linearly.

Finally, the translation error is mainly caused by the unevenness of the moving guide rail or mirror surface in the position measurement system. For example, the unevenness of the interferometer plane mirror will affect the position measurement. The translation error is that during the movement of the stage in the first direction (or the second direction), it has the same offset in the same value in the other direction, and the offset changes and is irregular at different values.

7 is a schematic diagram of a translation error provided by an embodiment of the present invention. Referring to FIG. 7, exemplarily, during the movement of the optical measurement stage in the Y direction, the actual position 201 of the alignment measurement mark 200 has the same offset dx at the same Y position relative to its standard position 202, but The offset dx at different Y positions varies and is irregular. Similarly, when the optical measurement stage is operating in the X direction During the moving process, the X translation error will cause the position measurement to have the same offset dy at the same X position relative to the standard position 202 of each alignment measurement mark 200, but the offset dy at different X positions will change without law.

Based on the above embodiments, this embodiment provides another method for measuring grid errors. FIG. 8 is a flowchart of another grid error measurement method provided by an embodiment of the present invention. Referring to FIG. 8, when the measured grid error is a rotation error, the method for measuring the grid error includes step S210, step S220, step S231, step S232, and step S233.

In step S210, the first actual position information of the preset alignment measurement mark on the substrate is acquired by the position measurement system in the optical device, wherein the substrate is horizontally adsorbed on the substrate adsorption table of the optical device at a first angle, It is assumed that the alignment measurement marks include at least two rows of alignment measurement marks in the second direction.

It should be noted that, since the rotation degree error is a linearly changing offset in the direction of the stage during movement in a certain direction, multiple sets of offsets in this direction need to be calculated. Exemplarily, in order to measure the rotation error in the Y direction, at least two columns of alignment measurement marks along the Y direction may be selected, and the offsets corresponding to the alignment measurement marks of different columns (ie, different X values) when calculating the same Y value The shift amount dy is used to calculate the corresponding offset amount dy for each Y value, so as to obtain the rotation error in the Y direction.

Similarly, in order to measure the rotation error in the X direction, at least two rows of alignment measurement marks along the X direction can be selected.

In step S220, the second actual position information of the preset alignment measurement mark is acquired by the position measurement system, wherein the substrate is horizontally adsorbed on the substrate adsorption table at a second angle, the first angle is 0 degrees, the second angle 180 degrees.

It should be noted that since the grid of the moving table and the grid of the measuring substrate may have rotation errors, the substrate is set to adsorb on the substrate adsorption table at 0 degrees and 180 degrees, and at 0 degrees and 180 degrees on the substrate. The measurement result of the time is the superposition of the rotation error of the two, and the rotation error in the position measurement system can be calculated more accurately according to the calculation results of the two.

In step S231, according to the first actual position information and the standard position information of the preset alignment measurement mark, it is determined that the first grid rotation degree of the grid is measured when the substrate is adsorbed on the substrate adsorption table at a 0-degree level.

In step S232, according to the second actual position information and the standard position information of the preset alignment measurement mark, it is determined that the second grid rotation degree of the grid is measured when the substrate is horizontally adsorbed on the substrate adsorption table at 180 degrees.

In step S233, the grid rotation degree error in the second direction of the position measurement system is calculated according to the first grid rotation degree and the second grid rotation degree.

It should be noted that the offset and grid rotation of the substrate at different angles need to be calculated, and the grid rotation error is determined by the two measured grid rotations.

In an embodiment, step S231 includes: calculating the first rotation amount of the alignment measurement mark pair according to the first actual position information and the standard position information of the alignment measurement mark pair, wherein the alignment measurement mark pair Contains two alignment measurement marks on the same line in the first direction, any first rotation amount Rotyn _0 satisfies: Rotyn _0=( pos_yj _0- pos_yi _0)/ (xj-xi ), pos_yi _0 is 0 The alignment value of the first actual position information of the first alignment measurement mark in the first alignment measurement mark alignment in the first degree, pos_yj _0 is the second alignment measurement in the alignment measurement mark alignment at 0 degrees The coordinate value of the first actual position information of the mark in the first direction, xi is the coordinate value of the standard position information of the first alignment measurement mark in the second direction, and xj is the standard position of the second alignment measurement mark The coordinate value of the message in the second direction; based on the first rotation amount and standard position information of a plurality of different alignment measurement mark pairs, the first grid rotation degree is calculated by linear fitting, wherein the linear fitting formula satisfies: Rotyn _0 = K 0×( yi + yj )/2+ dRotyn _0, K0 is the rotation degree of the first grid, yi is the coordinate value of the standard position information of the first alignment measurement mark in the first direction , Yj is the coordinate value of the standard position information of the second alignment measurement mark in the first direction, dRotyn _0 is the fitting residual at 0 degrees.

Step S232 includes: calculating the second rotation amount of the alignment measurement mark pair according to the second actual position information and the standard position information of the alignment measurement mark pair, any of the foregoing second rotation amounts Rotyn _180 satisfies: Rotyn _180= ( pos_yj _180- pos_yi _180)/(- xj + xi ), pos_yi _180 is the coordinate value in the first direction of the first actual position information of the first alignment measurement mark in the alignment measurement mark pair at 180 degrees, pos_yj _180 is the coordinate value of the first actual position information of the second alignment measurement mark in the aforementioned alignment measurement mark pair at 180 degrees in the aforementioned first direction; according to the second of multiple different alignment measurement mark pairs Rotation amount and standard position information, linear fitting calculates the rotation degree of the second grid, where the linear fitting formula satisfies: Rotyn _180= K 180×(- yi-yj )/2+ dRotyn _180, K180 is the aforementioned second grid Grid rotation degree, dRotyn _180 is the fitting residual at 180 degrees; correspondingly, the grid rotation error K_ws_z in the second direction in S233 satisfies the following formula: K_ws_z = ( K 0- K 180)/2.

9 is a schematic diagram of a rotation error provided by an embodiment of the present invention. Referring to FIG. 9, for example, taking the first direction as the X direction (the first direction is parallel to the X axis) and the second direction as the Y direction (the second direction is parallel to the Y axis), measured by the above grid error measurement method Y-axis grid error rotation.

First, select at least two rows of alignment measurement marks in the Y direction as preset alignment measurement marks, and standard position information 202 of each preset alignment measurement mark can be recorded in advance, for example, Mark1 And Mark2 is a pair of alignment measurement mark pairs with the same Y value in the X direction, Mark3 and Mark4 are another pair of alignment measurement mark pairs with the same Y value in the X direction, and the standard position information of Mark1 is recorded as (x1 , Y1), the standard position information of Mark2 is (x2, y2), and the standard position information of multiple pairs of different alignment measurement marks are sequentially recorded as (x3, y3), (x4, y4)... ( xN, yN).

Next, referring to FIG. 9(a), the substrate is adsorbed on the substrate adsorption stage of the optical device at a level of 0 degrees, and the first actual position information of the preset alignment measurement mark is measured in sequence. Exemplarily, record the first actual position information of Mark1 as ( pos_x 1_0, pos_y 1_0), and the first actual position information of Mark2 as ( pos_x 2_0, pos_y 2_0), and record the first An actual position message is ( pos_x 3_0, pos_y 3_0), ( pos_x 4_0, pos_y 4_0)......( pos_xN _0, pos_yN _0).

With Rotyn _0=( pos_yj _0- pos_yi _0)/( xj-xi ), calculate the first rotation amount corresponding to each alignment measurement mark pair Rotyn _0: Roty 12_0=( pos_y 2_0- pos_y 1_0)/( x 2 -x 1); Roty 34_0=( pos_y 4_0- pos_y 3_0)/( x 4- x 3);...... Roty ( N -1) N _0=( pos_yN _0- pos_y ( N -1)_0 )/( xN-x ( N -1)); where N is an even number. According to the obtained N/2 rotations and the position of y in the standard position information, linearly calculate the rotation of the first grid at 0 degrees Rotyn _0: Rotyn _0 = K 0× yn _0+ dRotyn _0; where, Rotyn _0 Take Roty 12_0, Roty 34_0, ... or Roty ( N -1) N _0; yn _0 takes ( y 1+ y 2)/2, ( y 3+ y 4)/2, ... or ( y ( N -1)+ yN )/2, dRotyn _0 is the fitting residual; that is, according to: Roty 12_0= K 0×( y 1+ y 2)/2+ dRoty 12_0; Roty 34_0= K 0×( y 3+ y 4)/2+ dRoty 34_0;...... Roty ( N -1) N _0 = K 0×( y ( N -1)+ yN )/2+ dRoty ( N -1) N _0; borrow By compensating for the respective fitting residuals, the first grid rotation K0 at 0 degrees is obtained by linear fitting.

Since the grid of the moving table and the grid of the measuring base may have rotation errors, 0 degrees is the obtained first grid rotation K0, which is the superposition of the rotation errors of the two: where K 0=( K_ws_y + K_plate_y ); K_ws_y is the grid rotation error of the motion table, and K_plate_y is the grid rotation error of the measurement substrate itself.

Next, referring to FIG. 9(b), the substrate is adsorbed on the substrate adsorption stage of the optical device at 180 degrees, and the second actual position information of the preset alignment measurement mark is measured in sequence. Exemplarily, record the second actual position information of Mark1 as ( pos_x 1_180, pos_y 1_180), and the second actual position information of Mark2 as ( pos_x 2_180, pos_y 2_180, and record the second of multiple pairs of different alignment measurement marks in sequence The actual position information is ( pos_x 3_180, pos_y 3_180), ( pos_x 4_180, pos_y 4_180)......( pos_xN _180, pos_yN _180).

With Rotyn _180=( pos_yj _0- pos_yi _0)/(- xj + xi ), calculate the first rotation amount corresponding to each alignment measurement mark pair Rotyn _180: Roty 12_180=( pos_y 2_180- pos_y 1_180)/(- x 2+ x 1); Roty 34_180=( pos_y 4_180- pos_y 3_180)/(- x 4+ x 3);...... Roty ( N -1) N _180=( pos_yN _180- pos_y ( N- 1)_180)/(- xN + x ( N -1)); based on the obtained N/2 rotations and the position of y in the standard position information, linearly calculate the rotation degree of the second grid at 180 degrees Rotyn _180: Rotyn _180 = K 180× yn _180+ dRotyn _180; where, Rotyn _180 takes Roty 12_180, Roty 34_180... or Roty ( N -1) N _180; yn _180 takes -( y 1+ y 2)/2, -( y 3+ y 4)/2... or -( y ( N -1)+ yN )/2, dRotyn _180 is the fitting residual; that is, according to: Roty 12_180=-( y 1+ y 2) /2× K 180+ dRoty 12_180; Roty 34_180=-( y 3+ y 4)/2× K 180+ dRoty 34_180;...... Roty ( N -1) N _180=-( y ( N- 1)+ yN )/2× K 180+ dRoty ( N -1) N _180; By compensating the respective fitting residuals, the linear fitting can obtain the second grid rotation degree K180 at 180 degrees.

Among them, K 180=-( K_ws_y-K_plate_y ).

According to K0 and K180, the Y-grid rotation error K_ws_y of the substrate stage can be obtained: K_ws_y = ( K 0- K 180)/2.

It can be understood that the method of measuring the rotation error K_ws_x of the X-grid of the substrate stage is similar to the measurement method provided in the above embodiment, and two lines (or multiple lines) of marks in the X direction on the substrate are selected for 0 degree and 180 degree measurement calibration , As shown in Figure 9(c) and 9(d).

The grid error measurement method provided in this embodiment calculates the grid rotation error of the position measurement system by calculating the actual position and standard position information of the substrate adsorbed on the substrate stage at different angles. The calculation method is simple and can be The measurement position of the position measurement system is calibrated, so that the final position measurement or movement position is accurate, and there is no need to collect the movement table in different postures (including rotation, (Tilt, etc.) Mathematical fitting calculation of a large range of position data to avoid the situation that the correlation data of multiple degrees of freedom cannot be obtained and the position model cannot be solved.

The embodiments of the present invention further provide another method for measuring grid errors. 10 is a flowchart of another grid error measurement method provided by an embodiment of the present invention. Referring to FIG. 10, when the measured grid error is a non-orthogonal error, the method for measuring the grid error includes step S310, step S320, step S331, step S332, and step S333.

In step S310, the first actual position information of the preset alignment measurement mark on the substrate is acquired by the position measurement system in the optical device, wherein the substrate is horizontally adsorbed on the substrate adsorption table of the optical device at a first angle, It is assumed that the alignment measurement marks include at least one line of alignment measurement marks in the first direction and at least one column of alignment measurement marks in the second direction.

It should be noted that, since the non-orthogonality error is the offset of a linear change in the direction perpendicular to the stage during the movement of the stage in a certain direction. Exemplarily, the motion table has a linearly changing X-direction offset during the movement in the Y direction. Since the grid of the motion table and the grid of the measurement substrate may have non-orthogonal errors, according to 0 degrees and 90 Degree measurement results, calculate the non-orthogonality error.

In step S320, the second actual position information of the preset alignment measurement mark is acquired by the position measurement system, wherein the substrate is horizontally adsorbed on the substrate adsorption table at a second angle, the first angle is 0 degrees, the second angle 90 degrees.

In step S331, the fitting calculation calculates the first non-orthogonal error Orth_0 of the measurement grid when the substrate is adsorbed on the substrate adsorption stage at a level of 0 degrees.

pos_xm _0 = Tx _0 + xm × Sx _0- ym × Rzy _0 + Res_xm _0; pos_ym _0 = Ty _0 + ym × Sy _0 + xm × Rzx _0 + Res_ym _0; Orth _0 = Rzy _0- Rzx _0; wherein, pos_xm _0 is 0 degrees The coordinate value of the first actual position information of any alignment measurement mark in the second direction of the alignment measurement mark is preset, pos_ym _0 is the first actual position information of any alignment measurement mark at 0 degrees The coordinate value in the first direction, xm is the coordinate value of the standard position information of any alignment measurement mark in the second direction, and ym is the coordinate of the standard position information of any alignment measurement mark in the first direction Value, Tx _0 is the translation of the entire alignment measurement mark at 0 degrees in the first direction, Ty _0 is the translation of the overall alignment measurement mark at 0 degrees in the second direction; Sx _0 is the first translation at 0 degrees The zoom magnification in one direction, Sy _0 is the zoom magnification in the second direction at 0 degrees; Rzx _0 represents the rotation around the coordinate axis parallel to the first direction at 0 degrees, Rzy _0 represents the parallel rotation at 0 degrees The rotation of the coordinate axis in two directions; Res_xm _0 is the positional residual of any alignment measurement mark in the first direction at 0 degrees, Res_ym _0 is the alignment measurement mark in the second direction of 0 degrees Position residual; in step S332, fitting and calculating the second non-orthogonal error Orth _90 of the measurement grid when the substrate is adsorbed on the substrate adsorption stage at a 90-degree level.

pos_xm _90 = Tx _90 + xm × Sx _90- ym × Rzy _90 + Res_xm _90; pos_ym _90 = Ty _90 + ym × Sy _90 + xm × Rzx _90 + Res_ym _90; Orth _90 = Rzy _90- Rzx_ 90; wherein, pos_xm _90 to 90 ° The coordinate value of the second actual position information of any alignment measurement mark in the second direction, pos_ym _90 is the coordinate value of the second actual position information of any alignment measurement mark in the first direction at 90 degrees, Tx _90 is the translation of the entire alignment measurement mark at 90 degrees in the first direction, Ty _90 is the translation of the overall alignment measurement mark at 90 degrees in the second direction; Sx _90 is the first direction at 90 degrees Upward zoom magnification, Sy _90 is the zoom magnification in the second direction at 90 degrees; Rzx _90 indicates rotation around the coordinate axis parallel to the first direction at 90 degrees, Rzy _90 indicates parallel to the second direction at 90 degrees The rotation of the coordinate axis; Res_xm _90 is the position residual of any alignment measurement mark in the first direction at 90 degrees, Res_ym _90 is the position residual of any alignment measurement mark in the second direction at 90 degrees difference.

In step S333, the grid non-orthogonal error Orth_ws of the position measurement system is calculated based on the first non-orthogonal error and the second non-orthogonal error.

Orth_ws = ( Orth _0+ Orth _90)/2.

FIG. 11 is a schematic diagram of a non-orthogonality error provided by an embodiment of the present invention. Referring to FIG. 11, for example, taking the first direction as the X direction and the second direction as the Y direction as an example, the grid non-orthogonal error is measured by the above grid error measurement method.

First, select the alignment measurement marks of one row and one column (or multiple rows and multiple columns) as the default alignment measurement marks. You can record the standard position information of each preset alignment measurement mark in advance, for example, record the standard position information of Mark1 Is (x1, y1), the standard position information of Mark2 is (x2, y2), and the standard position information of multiple pairs of different alignment measurement marks are recorded in sequence (x3, y3), (x4, y4)... .. (xM, yM).

Next, referring to FIG. 11(a), the substrate is adsorbed on the substrate adsorption stage of the optical device at a 0 degree level, and the first actual position information of the preset alignment measurement mark is measured in sequence. Exemplarily, record the first actual position information of Mark1 as ( pos_x 1_0, pos_y 1_0), and the first actual position information of Mark2 as ( pos_x 2_0, pos_y 2_0), and record the first An actual position message is ( pos_x 3_0, pos_y 3_0), ( pos_x 4_0, pos_y 4_0)... and ( pos_xM _0, pos_yM _0).

Based on the obtained first actual position information and standard position information of the M preset alignment measurement marks, fitting and calculating the first non-orthogonal error of the measurement grid at 0 degrees Orth _0: pos_x 1_0= Tx _0+ x 1 × Sx _0- y 1× Rzy _0+ Res _ x 1_0; pos_y 1_0= Ty _0+ y 1× Sy _0+ x 1× Rzx _0+ Res _ y 1_0; pos_x 2_0= Tx _0+ x 2× Sx _0- y 2× Rzy _0 Res _ x 2_0; pos_y 2_0 = Ty _0+ y 2× Sy _0+ x 2× Rzx _0+ Res _ y 2_0; ... pos_xm _0= Tx _0+ xm × Sx _0- ym × Rzy _0+ Res_xm _0; pos_ym _0 = Ty _0+ ym × Sy _0+ xm × Rzx _0+ Res_ym _0; fitting according to the above multiple formulas to get Rzx _0 and Rzy _0, and get the first non-orthogonal error Orth _0: Orth _0= Rzy _0- Rzx _0.

Since the grid of the moving table and the grid of the measuring base may have non-orthogonal errors, the first non-orthogonal error Orth _0 obtained at 0 degrees is the superposition of the non-orthogonal errors of the two: Orth _0= ( Orth_ws + Orth_plate ), Orth_ws is the grid non-orthogonal error of the motion table, Orth _ plate is the grid non-orthogonal error of the measurement substrate itself.

Next, referring to FIG. 11(b), the substrate is adsorbed on the substrate adsorption stage of the optical device at a 90-degree level, and the second actual position information of the preset alignment measurement mark is measured in sequence. Exemplarily, record the second actual position information of Mark1 as ( pos_x 1_90, pos_y 1_90), and the second actual position information of Mark2 as ( pos_x 2_90, pos_y 2_90), and record the first The second actual position information is ( pos_x 3_90, pos_y 3_90), ( pos_x 4_90, pos_y 4_90)......( pos_xM _90 , pos_yM _90 ).

Based on the obtained M second actual position information and standard position information, fitting and calculating the second non-orthogonal error Orth _90 of the measurement grid at 90 degrees: pos_x 1_90= Tx _90+ x 1× Sx _90- y 1× Rzy _90 + Res_x 1_90; pos_y 1_90 = Ty _90+ y 1× Sy _90 + x 1× Rzx_ 90+ Res _ y 1_90; pos_x 2_90= Tx _90+ x 2× Sx _90- y 2× Rzy_ 90+ Res _ x 2_90; pos_y 2_90 Ty _90+ y 2× Sy _90 + x 2× Rzx _90 + Res _ y 2_90;...... pos_xm _90 = Tx _90 + xm × Sx _90- ym × Rzy _90 + Res_xm _90 ; pos_ym _90 = Ty _90 + ym × Sy _90+ xm × Rzx _90 + Res_ym _90 ; fitting according to the above multiple formulas to obtain Rzy _90 and Rzx _90 , and the second non-orthogonality error Orth _90 : Orth _90 = Rzy _90- Rzx _90 .

Calculate the grid non-orthogonal error Orth_ws of the position measurement system according to Orth _0 and Orth _90 : Orth_ws = ( Orth _0+ Orth _90)/2.

The grid error measurement method provided in this embodiment calculates the grid non-orthogonal error of the position measurement system by calculating the actual position and standard position information of the substrate adsorbed on the substrate stage at different angles. The calculation method is simple. The measurement position of the position measurement system can be calibrated to make the final position measurement or movement position accurate, and there is no need to collect a large range of position data of the sports table in different postures (including rotation, tilt, etc.) for mathematical fitting calculation, Avoid situations where the correlation data of multiple degrees of freedom cannot be obtained and the position model cannot be solved.

The embodiments of the present invention further provide another method for measuring grid errors. FIG. 12 is a flowchart of another grid error measurement method provided by an embodiment of the present invention. Referring to FIG. 12, when the measured grid error is a translation error, the grid error measurement method includes steps S410, S420, S431, S432, and S433.

In step S410, the position measurement system in the optical device The first actual position information of the alignment measurement mark is set, wherein the substrate is horizontally adsorbed on the substrate adsorption table of the optical device at a first angle, and the preset alignment measurement mark includes at least one row of alignment amounts in the second direction测lagging.

In step S420, the second actual position information of the preset alignment measurement mark is acquired by the position measurement system, wherein the substrate is horizontally adsorbed on the substrate adsorption table at a second angle, the first angle is 0 degrees, the second angle 180 degrees.

In step S431, the fitting calculates the first translation error Res_xp _0 of the measurement grid when the substrate is adsorbed on the substrate adsorption stage at a 0-degree level.

pos_xp _0= Tx _0+ xp × Sx _0- yp × Rzy _0+ Res_xp _0; where pos_xp _0 is the preset alignment measurement mark at 0 degrees, the first actual position information of any alignment measurement mark is in the second direction Xp is the coordinate value of the standard position information of any alignment measurement mark in the second direction, yp is the coordinate value of the standard position information of any alignment measurement mark in the first direction, Tx _0 is the translation of the entire alignment measurement mark in the first direction at 0 degrees, Sx _0 is the zoom magnification in the first direction at 0 degrees, Rzy _0 indicates the rotation around the coordinate axis parallel to the second direction at 0 degrees Rotation; in step S432, the fitting calculates the second translation error Res_xp_180 of the measurement grid when the substrate is adsorbed on the substrate adsorption table at the aforementioned 180 degree level.

pos_xp _180= Tx _180+ xp × Sx _180- yp × Rzy _180+ Res_xp _180; where pos_xp _180 is the coordinate value of the second actual position information of any alignment measurement mark at 180 degrees in the second direction, Tx _180 is measured at 180 degrees integrally aligned in the first direction translating the mark, Sx _180 is a magnification in a first direction at 180 degrees, Rzy _180 represents a rotation about the axis 180 parallel to the second direction.

In step S433, the grid translation error Res_xp_ps in the first direction of the position measurement system relative to any alignment measurement mark is calculated based on the first translation error and the second translation error.

Res_xp_ps = ( Res_xp _0+ Res_xp _180)/2.

13 is a schematic diagram of a translation error provided by an embodiment of the present invention. Referring to FIG. 13, for example, taking the first direction as the X direction and the second direction as the Y direction as an example, the X-direction grid translation error is measured by the above-mentioned grid error measurement method.

First, select one row (or multiple rows) of alignment measurement marks as preset alignment measurement marks, as shown in FIG. 13(a), you can record the standard position information of each preset alignment measurement mark in advance, for example, record Mark1 The standard position information is (x1, y1), the standard position information of Mark2 is (x2, y2), and the standard position information of multiple pairs of different alignment measurement marks are sequentially recorded as (x3, y3), (x4, y4) ...(xP, yP).

Next, referring to FIG. 13(a), the substrate is adsorbed on the substrate adsorption table of the optical device at a level of 0 degrees, and the first actual position information of the preset alignment measurement mark is measured in sequence. Exemplarily, record the first actual position information of Mark1 as ( pos_x 1_0, pos_y 1_0), and the first actual position information of Mark2 as ( pos_x 2_0, pos_y 2_0), and record the first An actual position message is ( pos_x 3_0, pos_y 3_0), ( pos_x 4_0, pos_y 4_0)... and ( pos_xP _0, pos_yP _0).

Based on the obtained first actual position information and standard position information of the P preset alignment measurement marks, fit and calculate the first translation error of the measurement grid at 0 degrees Res_xp _0: pos_x 1_0= Tx _0+ x 1× Sx _0 -y 1× Rzy _0+ Res_x 1_0; pos_x 2_0= Tx _0+ x 2× Sx _0- y 2× Rzy _0+ Res_x 2_0; ... pos_xp _0= Tx _0+ xp × Sx _0- yp × Rzy _0+ Res_xp _0 ; Where Res_xp _0 is the position residual in the X direction, that is, the first translation residual in the X direction of the measurement grid at 0 degrees.

Since the motion table and the measurement base itself may have grid translation errors, the first translation residual Res_xp _0 is the superposition of the grid translation errors of the two; Res_xp _0 = Res_xp_ws + Res_xp_plate ; where, Res_xp_ps is the motion table at point p The X translation residual of the grid at Res_xp_plate is the X translation residual of the grid at point p of the substrate itself.

Next, referring to FIG. 13(b), the substrate is adsorbed on the substrate adsorption stage of the optical device at 180 degrees, and the second actual position information of the preset alignment measurement mark is measured in sequence. Exemplarily, record the second actual position information of Mark1 as ( pos_x 1_180, pos_y 1_180), and the second actual position information of Mark2 as ( pos_x 2_180, pos_y 2_180), and record the first The second actual position information is ( pos_x 3_180, pos_y 3_180), ( pos_x 4_180, pos_y 4_180)......( pos_xN _180, pos_yN _180).

Based on the obtained second actual position information and standard position information of the P preset alignment measurement marks, fit and calculate the second translation error Res_xp _180 of the measurement grid at 0 degrees: pos_x 1_180= Tx _180+ x 1× Sx_ 180 -y 1× Rzy _180+ Res_x 1_180; pos_x 2_180= Tx _180+ x 2× Sx _180- y 2× Rzy _180+ Res_x 2_180;...... pos_xp _180= Tx _180+ xp × Sx _180- yp × Rzy _180+ Res_xp _180 ; wherein, Res_xp _180 X to the position residuals, i.e. the measuring grid at 180 X of the second translation residuals.

Among them, Res_xp _180= Res_xp_ws - Res_xp_plate .

According to Res_xp _0 and Res_xp _180, the translation error of the substrate stage in the X direction grid can be obtained.

Res_xp_ps = ( Res_xp _0+ Res_xp _180)/2.

It can be understood that the method of measuring the translation error of the Y-grid of the substrate stage Res_yp_ps is similar to the measurement method provided in the above embodiment, and a column (or multiple columns) of markers on the substrate in the Y direction are used for the measurement and calibration of 0 degrees and 180 degrees, such as Figures 13(c) and 13(d).

The grid error measurement method provided in this embodiment calculates the grid translation error of the position measurement system by calculating the actual position and standard position information of the substrate adsorbed on the substrate stage at different angles. The measurement position of the measurement system is calibrated, so that the final position measurement or movement position is accurate, and there is no need to collect a large range of position data of the movement table in different postures (including rotation, tilt, etc.) for mathematical fitting calculation, to avoid being unable to obtain The situation that the correlation data of multiple degrees of freedom prevents the position model from being solved.

In order to measure the grid error in the position measurement system using the grid error measurement method provided in the above embodiment. The embodiment of the invention further provides a grid error measuring device.

14 is a structural block diagram of a grid error measurement device provided by an embodiment of the present invention. As shown in FIG. 14, the grid error measuring device includes: a first actual position information module 51, which is configured to acquire the first actual position of the preset alignment measurement mark on the substrate by the position measuring system in the optical device Message, wherein the substrate is provided with a plurality of alignment measurement marks arranged in an array along the first direction and the second direction to form a measurement grid, and the substrate is horizontally adsorbed on the substrate adsorption table of the optical device at a first angle, The first direction and the second direction are perpendicular; the second actual position information acquisition module 52 is set to acquire the second actual position information of the preset alignment measurement mark by the position measurement system, wherein the substrate is horizontal at the second angle Adsorbed on the substrate adsorption table, the second angle is different from the first angle; grid error calculation mode Group 53 is set to calculate the grid error of the position measurement system based on the first actual position information, the second actual position information, and the standard position information of the preset alignment measurement mark.

In an embodiment, the first direction is parallel to the X axis in the preset coordinate system, and the second direction is parallel to the Y axis in the preset coordinate system; or, the first direction is parallel to the Y axis in the preset coordinate system, The second direction is parallel to the X axis in the aforementioned preset coordinate system.

The grid error measurement device can measure different types of grid errors in the position measurement system by the grid error measurement method in the above embodiment, by adsorbing the substrate on the substrate adsorption table at different adsorption angles, and obtaining Preset the actual position information of the alignment measurement marks at different adsorption angles, and calculate the grid error of the position measurement system. The calculation method is simple. The measurement position of the position measurement system can be calibrated to make the final position measurement or movement position. Accurate, and does not need to collect a large range of position data of the motion table in different poses (including rotation, tilt, etc.) for mathematical fitting calculation, to avoid the situation that the correlation data of multiple degrees of freedom cannot be obtained and the position model cannot be solved .

In one embodiment, the preset alignment measurement mark includes at least two rows of the alignment measurement mark in the second direction, the first angle is 0 degrees, and the second angle is 180 degrees.

The grid error calculation module includes a first grid rotation degree determination unit, a second grid rotation degree determination unit, and a grid rotation degree error calculation unit.

The first grid rotation degree determining unit is set to determine the first grid of the measuring grid when the substrate is adsorbed on the substrate adsorption table at a 0 degree level according to the first actual position information and the standard position information of the preset alignment measurement mark Grid rotation.

The second grid rotation degree determining unit is configured to determine the second grid of the measuring grid when the substrate is adsorbed on the substrate adsorption table at a 180-degree level according to the second actual position information and the standard position information of the preset alignment measurement mark Grid rotation.

The grid rotation degree error calculation unit is configured to calculate the grid rotation degree error in the second direction of the position measurement system according to the first grid rotation degree and the second grid rotation degree.

In an embodiment, the first grid rotation degree determination unit includes a first rotation amount calculation subunit and a first grid rotation degree fitting subunit.

The first rotation amount calculation subunit is configured to calculate the first rotation amount of the alignment measurement mark pair based on the first actual position information and the standard position information of the alignment measurement mark pair, wherein the alignment measurement mark pair includes The two aforementioned alignment measurement marks on the same line in the first direction, any of the aforementioned first rotation amounts Rotyn _0 satisfies: Rotyn _0=( pos_yj _0- pos_yi _0)/( xj-xi ), pos_yi _0 is The coordinate value of the first actual position information of the first alignment measurement mark in the aforementioned alignment measurement mark pair at 0 degrees in the first direction, pos_yj _0 is the second alignment of the alignment measurement mark pair at 0 degrees The coordinate value of the first actual position information of the measurement mark in the first direction, xi is the coordinate value of the standard position information of the first alignment measurement mark in the second direction, and xj is the coordinate value of the second alignment measurement mark The coordinate value of the standard position information in the second direction.

The first grid rotation degree fitting sub-unit is set to calculate the first grid rotation degree based on the first rotation amount and standard position information of a plurality of different alignment measurement mark pairs, wherein the linear fitting formula Satisfy: Rotyn _0 = K 0×( yi + yj )/2+ dRotyn _0, K0 is the aforementioned first grid rotation degree, yi is the coordinate value of the standard position information of the first alignment measurement mark in the first direction , Yj is the coordinate value of the standard position information of the second alignment measurement mark in the first direction, dRotyn _0 is the fitting residual at 0 degrees.

The second grid rotation degree determination unit includes a second rotation amount calculation subunit and a second grid rotation degree fitting subunit.

The second rotation amount calculation sub-unit is configured to calculate the second rotation amount of the alignment measurement mark pair based on the second actual position information and the standard position information of the alignment measurement mark pair, and any second rotation amount Rotyn _180 satisfies : Rotyn _180=( pos_yj _180- pos_yi _180)/(- xj + xi ), pos_yi _180 is the first actual position information of the first alignment measurement mark in the aforementioned alignment measurement mark pair at 180 degrees on the first side The upward coordinate value, pos_yj_180 is the coordinate value of the first actual position information of the second alignment measurement mark in the alignment measurement mark pair at 180 degrees in the first direction.

The second grid rotation degree fitting subunit is configured to calculate the aforementioned second grid rotation degree according to the second rotation amount and standard position information of a plurality of different alignment measurement mark pairs, wherein, the linear fitting The formula satisfies: Rotyn _180 = K 180×(- yi-yj )/2+ dRotyn_ 180, K180 is the rotation degree of the second grid, and dRotyn_180 is the fitting residual at 180 degrees.

Correspondingly, the grid rotation error K _ ws_z in the second direction of the position measurement system is calculated according to the first grid rotation and the second grid rotation to satisfy the following formula: K _ ws_z = ( K 0- K 180)/ 2.

In one embodiment, the preset alignment measurement mark includes at least one line of alignment measurement marks in the first direction and at least one column of alignment measurement marks in the second direction. The first angle is 0 degrees, the first The second angle is 90 degrees.

The grid error calculation module includes a first non-orthogonal fitting unit, a second non-orthogonal fitting unit, and a grid non-orthogonal error calculation unit.

The first non-orthogonal fitting unit is set to fit and calculate the first non-orthogonal error Orth _0 of the measurement grid when the substrate is adsorbed on the substrate adsorption platform at the aforementioned 0 degree level Orth _0: pos_xm _0= Tx _0+ xm × Sx _0- ym × Rzy _0+ Res_xm _0; pos_ym _0 = Ty _0+ ym × Sy _0+ xm × Rzx _0+ Res_ym _0; Orth _0= Rzy _0- Rzx _0; where pos_xm _0 is the preset alignment measurement at 0 degrees The coordinate value of the first actual position information of any alignment measurement mark in the aforementioned second direction, pos_ym _0 is the coordinate of the first actual position information of any alignment measurement mark in the first direction at 0 degrees Value, xm is the coordinate value of the standard position information of any alignment measurement mark in the second direction, ym is the coordinate value of the standard position information of any alignment measurement mark in the first direction, Tx _0 is 0 The translation of the entire measurement mark in the first direction under the degree, Ty _0 is the translation of the entire measurement mark in the second direction at 0 degrees; Sx _0 is the zoom magnification in the first direction at 0 degrees , Sy _0 is the zoom magnification in the second direction at 0 degrees; Rzx _0 represents the rotation around the coordinate axis parallel to the first direction at 0 degrees, Rzy _0 represents the rotation around the coordinate axis parallel to the second direction at 0 degrees Rotation; Res_xm _0 is the positional residual of any alignment measurement mark in the first direction at 0 degrees, and Res_ym _0 is the positional residual of any alignment measurement mark in the second direction at 0 degrees.

The second non-orthogonal fitting unit is set to fit and calculate the second non-orthogonal error of the measurement grid when the substrate is adsorbed on the substrate adsorption platform at a 90-degree level: Orth_90: pos_xm_90=Tx_90+xm×Sx_90-ym× Rzy_90+Res_xm_90; pos_ym_90=Ty_90+ym×Sy_90+xm×Rzx_90+Res_ym_90; Orth _90 = Rzy _90- Rzx _90 ; where pos_xm _90 is the second actual position information of any alignment measurement mark at 90 degrees The coordinate value in the two directions, pos_ym _90 is the coordinate value of the second actual position information of any alignment measurement mark at 90 degrees in the first direction, Tx _90 is the overall alignment measurement mark at 90 degrees in the first place The translation in the direction, Ty _90 is the translation of the entire measurement mark at 90 degrees in the aforementioned second direction; Sx _90 is the zoom magnification in the first direction at 90 degrees, Sy _90 is the second at 90 degrees Zoom magnification in the direction; Rzx_90 means rotation around the coordinate axis parallel to the first direction at 90 degrees, Rzy _90 means rotation around the coordinate axis parallel to the second direction at 90 degrees; Res_xm _90 is any value under 90 degrees The position residual of the alignment measurement mark in the first direction, Res_ym _90 is the position residual of any alignment measurement mark in the second direction at 90 degrees.

The grid non-orthogonal error calculation unit is set to calculate the grid non-orthogonal error of the position measurement system based on the first non-orthogonality and the second non-orthogonality Orth_ws : Orth_ws = ( Orth _0+ Orth _90)/2 .

In one embodiment, the preset alignment measurement mark includes at least one row of alignment measurement marks in the second direction, the first angle is 0 degrees, and the second angle is 180 degrees.

The grid error calculation module includes a first translation error fitting unit, a second translation error fitting unit, and a grid translation error calculation unit.

A first translation error fitting means to fit calculation adsorbing the substrate to a first level of translation 0 Res_xp _0 measurement error grid when the substrate adsorption stage: pos_xp _0 = Tx _0 + xp × Sx _0- yp × Rzy _0 + Res_xp _0; where pos_xp _0 is the coordinate value in the second direction of the first actual position information of any alignment measurement mark in the preset alignment measurement mark at 0 degrees, xp is any alignment measurement mark The coordinate value of the standard position information in the second direction, yp is the coordinate value of the standard position information of any alignment measurement mark in the first direction, Tx _0 is the alignment measurement mark at 0 degrees. translational direction, Sx_ 0 is the magnification in the first direction at 0 degree, Rzy _0 about a coordinate axis parallel to the second direction at 0 degrees rotation.

The second translation error fitting unit is set to fit and calculate the second translation error of the measurement grid when the substrate is adsorbed on the substrate adsorption stage at 180 degrees horizontally. Res_xp _180: pos_xp _180= Tx _180+ xp × Sx _180- yp × Rzy _180+ Res_xp _180; where pos_xp _180 is the coordinate value of the second actual position information of any alignment measurement mark at 180 degrees in the second direction, Tx _180 is the overall alignment measurement mark at 180 degrees in the first direction translation, Sx_180 the scaling factor in the first direction 180 degrees, Rzy _180 represents a rotational direction about an axis parallel to the second axis by 180 degrees.

The grid translation error calculation unit is set to calculate the grid translation error in the first direction of the position measurement system relative to any alignment measurement mark based on the first translation error and the second translation error Res_xp_ps : Res_xp_ps = ( Res_xp _0+ Res_xp _180 )/2.

An embodiment of the present invention further provides an optical device including the grid error measuring device provided by any of the above embodiments.

In one embodiment, the optical device includes a lithography machine.

The optical device provided in this embodiment calculates the grid error of the aforementioned position measurement system by calculating the actual position and standard position information of the substrate adsorbed on the substrate stage at different angles, the calculation method is simple, and the measurement position of the position measurement system can be measured Carry out calibration to make the final position measurement or motion position accurate, and do not need to collect a large range of position data of the motion table in different postures (including rotation, tilt, etc.) for mathematical fitting calculation, avoiding the inability to obtain multiple degrees of freedom Correlation data makes it impossible to solve the position model.

The present invention claims the priority of the Chinese patent application filed on June 28, 2018 in the China Patent Office with the application number 201810688910.1. The entire content of the application is incorporated by reference in the present invention.

Claims (16)

A method for measuring grid error, characterized in that it includes: acquiring the first actual position information of a preset alignment measurement mark on a substrate by a position measurement system in an optical device, wherein the substrate is provided with a plurality of edges The first direction and the second direction are aligned measurement marks arranged in an array to form a measurement grid, the substrate is horizontally adsorbed on the substrate adsorption table of the optical device at a first angle, the first direction and the second direction Vertical; acquiring the second actual position information of the preset alignment measurement mark by the position measurement system, wherein the substrate is horizontally adsorbed on the substrate adsorption table at a second angle, and the second angle is different from the first An angle; calculating the grid error of the position measurement system based on the first actual position information, the second actual position information, and the standard position information of the preset alignment measurement mark. The method for measuring grid errors as described in item 1 of the patent application scope, wherein the first direction is parallel to the X axis in the preset coordinate system, and the second direction is parallel to the Y axis in the preset coordinate system; Alternatively, the first direction is parallel to the Y axis in the preset coordinate system, and the second direction is parallel to the X axis in the preset coordinate system. The method for measuring grid error as described in item 2 of the patent application scope, wherein the preset alignment measurement mark includes at least two rows of the alignment measurement mark in the second direction, and the first angle is 0 degrees, the second angle is 180 degrees; calculating the grid error of the position measurement system based on the first actual position information, the second actual position information, and the standard position information of the preset alignment measurement mark, including: According to the first actual position information and the standard position information of the preset alignment measurement mark, confirm The first grid rotation degree of the grid is measured when the substrate is adsorbed on the substrate adsorption table at the 0-degree level; based on the second actual position information and the standard position information of the preset alignment measurement mark, the aforesaid is determined The second grid rotation of the grid is measured when the substrate is adsorbed on the substrate adsorption platform at the 180 degree level; the second of the position measurement system is calculated according to the first grid rotation and the second grid rotation The grid rotation error in the direction. The grid error measurement method as described in item 3 of the patent application scope, wherein, based on the first actual position information and the standard position information of the preset alignment measurement mark, it is determined that the substrate is adsorbed at the 0 degree level The first grid rotation degree of the measurement grid when on the substrate adsorption table includes: calculating the first rotation amount of the alignment measurement mark pair according to the first actual position information and the standard position information of the alignment measurement mark pair Where the pair of alignment measurement marks includes two alignment measurement marks located in the same row in the first direction, and any of the first rotation amounts Rotyn _0 satisfies: Rotyn _0=( pos_yj _0- pos_yi _0)/( xj-xi ), pos_yi _0 is the coordinate value of the first actual position information of the first alignment measurement mark in the first alignment measurement mark pair in the first direction at 0 degrees, pos_yi _0 is 0 The first actual position information of the second alignment measurement mark in the alignment measurement mark pair in the first direction, xi is the standard position information of the first alignment measurement mark in the first The coordinate value in two directions, xj is the coordinate value of the standard position information of the second alignment measurement mark in the second direction; the first rotation amount and the standard position information of the pair of measurement alignment marks according to multiple different alignments , The linear fitting calculates the aforementioned first grid rotation degree, where the linear fitting formula satisfies: Rotyn _0 = K 0×( yi + yj )/2+ dRotyn _0, K0 is the aforementioned first grid rotation degree, yi is The coordinate value of the standard position information of the first alignment measurement mark in the first direction, yj is the coordinate value of the standard position information of the second alignment measurement mark in the first direction, dRotyn _0 is 0 Fitting error at degree; according to the second actual position information and the standard position information of the preset alignment measurement mark, determine the first measurement of the grid when the substrate is adsorbed on the substrate adsorption table at the 180 degree level The two grid rotation degrees include: calculating the second rotation amount of the alignment measurement mark pair according to the second actual position information and the standard position information of the alignment measurement mark pair, any of the foregoing second rotation amounts Rotyn _180 Satisfy: Rotyn _180=( pos_yj _180- pos_yi _180)/(- xj + xi ), pos_yi _180 is the first actual position information of the first alignment measurement mark in the aforementioned alignment measurement mark pair at 180 degrees. The coordinate value in one direction, pos_yj _180 is the coordinate value of the first actual position information of the second alignment measurement mark in the aforementioned alignment measurement mark pair at 180 degrees in the aforementioned first direction; according to multiple different alignments The second rotation amount and standard position information of the mark pair are measured, and the second grid rotation degree is calculated by linear fitting, wherein the linear fitting formula satisfies: Rotyn_ 180 = K 18 0×(- yi - yj )/2+ dRotyn _180, K180 is the rotation degree of the second grid described above, dRotyn _180 is the fitting residual at 180 degrees; according to the rotation degree of the first grid and the second grid Rotation degree calculation The grid rotation degree error K_ws_z in the aforementioned second direction of the aforementioned position measurement system satisfies the following formula: K_ws_z = ( K 0- K 180)/2. The method for measuring grid errors as described in item 2 of the patent application scope, wherein the preset alignment measurement mark includes at least one line of the alignment measurement mark in the first direction and in the second direction At least one row of the alignment measurement marks, the first angle is 0 degrees, and the second angle is 90 degrees; based on the first actual position information, the second actual position information, and the preset alignment measurement marks The standard position information calculates the grid error of the position measurement system, including: fitting and calculating the first non-orthogonal error of the measurement grid when the substrate is adsorbed on the substrate adsorption table at the level of 0 degrees Orth _0: pos_xm _0= Tx _0+ xm × Sx _0- ym × Rzy _0+ Res_xm _0; pos_ym _0 = Ty _0+ ym × Sy _0+ xm × Rzx _0+ Res_ym _0; Orth _0 = Rzy _0- Rzx _0; where pos_xm_previous is 0 The coordinate value of the first actual position information of any alignment measurement mark in the alignment measurement mark in the aforementioned second direction, pos_ym _0 is the first actual position information of any alignment measurement mark at 0 degrees at The coordinate value in the first direction, xm is the coordinate value of the standard position information of any alignment measurement mark in the second direction, and ym is the standard position information of any alignment measurement mark in the first position The coordinate value in one direction, Tx_0 is the translation of the entire alignment measurement mark at 0 degrees in the first direction, Ty _0 is the translation of the entire alignment measurement mark at 0 degrees in the second direction ; Sx _0 is the zoom magnification in the aforementioned first direction at 0 degrees, Sy _0 is the zoom magnification in the aforementioned second direction at 0 degrees; Rzx _0 represents a coordinate axis parallel to the aforementioned first direction at 0 degrees Rotation, Rzy _0 means rotation around the coordinate axis parallel to the aforementioned second direction at 0 degrees; Res_xm _0 is the positional residual of any of the alignment measurement marks in the aforementioned first direction at 0 degrees, Res_ym _0 is 0 The position residual error of any of the aforementioned alignment measurement marks in the aforementioned second direction; fitting and calculating the second non-orthogonal error of the measurement grid when the aforementioned substrate is adsorbed on the aforementioned substrate adsorption platform at the aforementioned 90-degree level Orth _90: pos_xm _90 = Tx _90 + xm × Sx _90- ym × Rzy _90 + Res_xm _90; pos_ym _90 = Ty _90 + ym × Sy _90 + xm × Rzx _90 + Res_ym _90; Orth _90 = Rzy _90- Rzx _90; wherein, pos_xm _90 is The second actual position information of any of the aforementioned alignment measurement marks is at the front at 90 degrees The coordinate value in the second direction, pos_ym _90 is the coordinate value of the second actual position information of any of the alignment measurement marks at 90 degrees in the first direction, Tx _90 is the alignment measurement at 90 degrees Translation of the entire mark in the first direction, Ty _90 is the translation of the entire alignment measurement mark in the second direction at 90 degrees; Sx _90 is the zoom magnification in the first direction at 90 degrees, Sy _90 is the zoom magnification in the aforementioned second direction at 90 degrees; Rzx _90 indicates the rotation around the coordinate axis parallel to the aforementioned first direction at 90 degrees, Rzy _90 indicates the coordinate axis parallel to the aforementioned second direction at 90 degrees The rotation of Res_xm _90 is the position residual of the aforementioned alignment measurement mark in the first direction at 90 degrees, Res_ym _90 is the position of the aforementioned alignment measurement mark in the second direction at 90 degrees Residual error; calculate the grid non-orthogonal error Orth_ws of the position measurement system based on the first non-orthogonal error and the second non-orthogonal error: Orth_ws = ( Orth _0+ Orth _90)/2. The method for measuring grid error as described in item 2 of the patent application scope, wherein the preset alignment measurement mark includes at least one row of the alignment measurement mark in the second direction, and the first angle is 0 Degree, the second angle is 180 degrees; calculating the grid error of the position measurement system based on the first actual position information, the second actual position information, and the standard position information of the preset alignment measurement mark, including: Summing up the first translation error of the measurement grid when the aforementioned substrate is adsorbed on the aforementioned substrate adsorption platform at the aforementioned 0 degree level Res_xp _0: pos_xp _0= Tx _0+ xp × Sx _0- yp × Rzy _0+ Res_xp _0; where pos_xp _0 is At 0 degrees, the coordinate value of the first actual position information of any alignment measurement mark in the preset alignment measurement mark in the second direction, xp is the standard position information of any alignment measurement mark in The coordinate value in the second direction, yp is the coordinate value of the standard position information of any of the alignment measurement marks in the first direction, Tx _0 is the overall alignment measurement mark at 0 degrees at the first The translation in the direction, Sx _0 is the zoom magnification in the first direction at 0 degrees, Rzy _0 represents the rotation around the coordinate axis parallel to the second direction at 0 degrees; fitting calculates the aforementioned substrate at the aforementioned 180 degree level The second translation error Res_xp _180 of the measurement grid when adsorbed on the aforementioned substrate adsorption table: pos_xp _180= Tx _180+ xp × Sx _180- yp × Rzy _180+ Res_xp _180; where pos_xp _180 is any of the aforementioned alignment amounts at 180 degrees The coordinate value of the second actual position information of the measurement mark in the second direction, Tx _180 is the translation of the entire alignment measurement mark in the first direction at 180 degrees, and Sx _180 is the first translation in the first direction at 180 degrees The zoom magnification in the direction, Rzy _180 represents the rotation around the coordinate axis parallel to the second direction at 180 degrees; calculate the alignment amount of the position measurement system relative to any of the foregoing based on the first translation error and the second translation error Measure the grid translation error Res_xp_ps in the aforementioned first direction of the mark : Res_xp_ps = ( Res_xp _0+ Res_xp _180)/2. The method for measuring grid errors as described in any one of the items 1 to 6 of the patent application range, wherein the pattern of the alignment measurement mark is a center symmetric figure. The measurement method of grid error as described in any of items 1 to 6 of the patent application scope, which In the above, the aforementioned position measuring system is an interferometer measuring system, a laser triangle ruler or a laser displacement sensor. A grid error measuring device, characterized in that it includes: a first actual position information module configured to obtain the first actual position information of a preset alignment measurement mark on the substrate by a position measuring system in an optical device, Wherein, the substrate is provided with a plurality of alignment measurement marks arranged in an array along the first direction and the second direction to form a measurement grid, and the substrate is horizontally adsorbed on the substrate adsorption table of the optical device at a first angle , The first direction and the second direction are perpendicular; the second actual position information acquisition module is configured to acquire the second actual position information of the preset alignment measurement mark by the position measurement system, wherein the substrate Adsorbed horizontally on the substrate suction table at a second angle, the second angle is different from the first angle; the grid error calculation module is set based on the first actual position information, the second actual position information and the The standard position information of the alignment measurement mark is set to calculate the grid error of the aforementioned position measurement system. The grid error measuring device described in item 9 of the patent application scope, wherein the first direction is parallel to the X axis in the preset coordinate system, and the second direction is parallel to the Y axis in the preset coordinate system; Alternatively, the first direction is parallel to the Y axis in the preset coordinate system, and the second direction is parallel to the X axis in the preset coordinate system. A grid error measuring device as described in item 10 of the patent application range, wherein the preset alignment measurement mark includes at least two rows of the alignment measurement mark in the second direction, and the first angle is 0 degrees, the second angle is 180 degrees; the grid error calculation module includes: The first grid rotation degree determining unit is configured to determine the measurement grid when the substrate is adsorbed on the substrate adsorption stage at the level of 0 degrees based on the first actual position information and the standard position information of the preset alignment measurement mark The first grid rotation degree of the grid; the second grid rotation degree determination unit is configured to determine that the substrate is adsorbed at the 180-degree horizontal level according to the second actual position information and the standard position information of the preset alignment measurement mark The second grid rotation degree of the grid is measured while on the substrate adsorption table; the grid rotation degree error calculation unit is set to calculate the position measurement system based on the first grid rotation degree and the second grid rotation degree The grid rotation error in the aforementioned second direction. The grid error measuring device as described in item 11 of the patent application range, wherein the first grid rotation degree determination unit includes: a first rotation amount calculation subunit, which is set to measure the first of the pair of marks according to the alignment measurement The actual position information and the standard position information calculate the first rotation amount of the alignment measurement mark pair, wherein the alignment measurement mark pair includes two of the alignment measurements on the same line in the first direction Mark, any of the aforementioned first rotation amount Rotyn _0 satisfies: Rotyn _0=( pos_yj _0- pos_yi _0)/( xj-xi ), pos_yi _0 is the first alignment measurement in the aforementioned alignment measurement mark pair at 0 degrees The coordinate value of the first actual position information of the mark in the first direction, pos_yj _0 is the first actual position information of the second alignment measurement mark in the alignment measurement mark pair at 0 degrees in the first direction The coordinate value of xi is the coordinate value of the standard position information of the first alignment measurement mark in the second direction, and xj is the coordinate of the standard position information of the second alignment measurement mark in the second direction Value; the first grid rotation degree fitting subunit is set to calculate the aforementioned first grid rotation degree according to the first rotation amount and standard position information of a plurality of different alignment measurement mark pairs, wherein, linear The fitting formula satisfies: Rotyn _0 = K 0×( yi + yj )/2+ dRotyn _0, K0 is the rotation degree of the first grid, and yi is the standard position information of the first alignment measurement mark. The coordinate value in the direction, yj is the coordinate value of the standard position information of the second alignment measurement mark in the first direction, dRotyn _0 is the fitting residual at 0 degrees; the rotation degree of the second grid is determined The unit includes: a second rotation amount calculation sub-unit configured to calculate the second rotation amount of the alignment measurement mark pair based on the second actual position information and the standard position information of the alignment measurement mark pair, any of the foregoing The two rotation amounts Rotyn _180 satisfies: Rotyn _180=( pos_yj _180- pos_yi _180)/(- xj + xi ), pos_yi _180 is the first actuality of the first alignment measurement mark in the aforementioned alignment measurement mark pair at 180 degrees The coordinate value of the position information in the first direction, pos_yj _180 is the coordinate value of the first actual position information of the second alignment measurement mark in the alignment measurement mark pair at 180 degrees in the first direction; The second grid rotation degree fitting subunit is set to calculate the foregoing second grid rotation degree according to the second rotation amount and standard position information of a plurality of different alignment measurement mark pairs, wherein the linear fitting formula Satisfy: Rotyn _180 = K 180×(- yi-yj )/2+ dRotyn _180, K180 is the aforementioned second grid rotation degree, dRotyn _1 80 is the fitting residual error at 180 degrees; the grid rotation error K_ws_z in the second direction of the position measurement system is calculated according to the first grid rotation degree and the second grid rotation degree to satisfy the following formula: K_ws_z = ( K 0- K 180)/2. A grid error measuring device as described in item 10 of the patent application range, wherein the preset alignment measurement mark includes at least one line of the alignment measurement mark in the first direction and in the second direction At least one row of the alignment measurement marks, the first angle is 0 degrees, the second angle is 90 degrees; the grid error calculation module includes: a first non-orthogonal fitting unit, which is set for fitting calculation The first non-orthogonal error Orth _0 of the measurement grid when the aforementioned substrate is adsorbed on the aforementioned substrate adsorption platform at the aforementioned 0 degree level: pos_xm _0= Tx _0+ xm × Sx _0- ym × Rzy _0+ Res_xm _0; pos_ym _0= Ty _0+ ym × Sy _0+ xm × Rzx _0+ Res_ym _0; Orth _0= Rzy _0- Rzx _0; where pos_xm _0 is the first actual position of any of the aforementioned alignment measurement marks at 0 degrees The coordinate value of the message in the aforementioned second direction, pos_ym _0 is the coordinate value of the first actual position of the aforementioned alignment measurement mark at 0 degrees in the aforementioned first direction, and xm is any of the aforementioned alignment measurement The coordinate value of the standard position information of the mark in the aforementioned second direction, ym is the coordinate value of the standard position information of any of the aforementioned alignment measurement marks in the aforementioned first direction, Tx _0 is the aforementioned alignment measurement at 0 degrees Translation of the entire mark in the first direction, Ty _0 is the translation of the entire alignment measurement mark in the second direction at 0 degrees; Sx _0 is the zoom magnification in the first direction at 0 degrees, Sy _0 is the zoom magnification in the second direction at 0 degrees; Rzx _0 represents the rotation around the coordinate axis parallel to the first direction at 0 degrees, Rzy _0 represents the coordinate axis parallel to the second direction at 0 degrees Of rotation; Res_xm _0 is the position residual of the aforementioned alignment measurement mark in the first direction at 0 degrees, Res_ym _0 is the position of the aforementioned alignment measurement mark in the second direction at 0 degrees Residual; second non-orthogonal fitting unit, set to fit and calculate the second non-orthogonal error of the measurement grid when the aforementioned substrate is adsorbed on the aforementioned substrate adsorption platform at the aforementioned 90-degree level Orth _90 : pos_xm _90 = Tx _90+ xm × Sx _90- ym × Rzy _90 + Res_xm _90 ; pos_ym _90 = Ty _90 + ym × Sy _90 + xm × Rzx _90 + Res_ym _90 ; Orth _90 = Rzy _90- Rzx _90 ; where, pos_xm_ below 90 The coordinate value of the second actual position information aligned with the measurement mark in the aforementioned second direction, pos_ym _90 is the coordinate value of the second actual position information of any of the alignment measurement marks in the first direction at 90 degrees, Tx_90 is the translation of the entire alignment measurement marks in the first direction at 90 degrees , Ty _90 is the translation of the entire alignment measurement mark in the second direction at 90 degrees; Sx_ 90 is the zoom magnification in the first direction at 90 degrees, and Sy _90 is the second direction at 90 degrees Rzx _90 represents the rotation around the coordinate axis parallel to the aforementioned first direction at 90 degrees, Rzy _90 represents the rotation about the coordinate axis parallel to the aforementioned second direction at 90 degrees; Res_xm_ 90 is the foregoing at 90 degrees The position residual of any alignment measurement mark in the first direction, Res_ym _90 is the position residual of any alignment measurement mark in the second direction at 90 degrees; grid non-orthogonality error The calculation unit is configured to calculate the grid non-orthogonal error Orth_ws of the position measurement system based on the first non-orthogonal error and the second non-orthogonal error: Orth_ws = ( Orth _0+ Orth _90)/2. The grid error measuring device as described in item 10 of the patent application range, wherein the preset alignment measurement mark includes at least one row of the alignment measurement mark in the second direction, and the first angle is 0 Degrees, the second angle is 180 degrees; the grid error calculation module includes: a first translation error fitting unit, configured to fit and calculate the grid when the substrate is adsorbed on the substrate adsorption table at the level of 0 degrees Res_xp _0 of the first translation error: pos_xp _0= Tx _0+ xp × Sx _0- yp × Rzy _0+ Res_xp _0; where pos_xp _0 is any of the alignment measurement marks in the aforementioned preset alignment measurement marks at 0 degrees The coordinate value of the first actual position information in the aforementioned second direction, xp is the coordinate value of the standard position information of any of the aforementioned alignment measurement marks in the aforementioned second direction, and yp is the coordinate value of any of the aforementioned alignment measurement marks The coordinate value of the standard position information in the first direction, Tx_0 is the translation of the entire alignment measurement mark in the first direction at 0 degrees, Sx _0 is the zoom magnification in the first direction at 0 degrees, Rzy _0 represents the rotation around the coordinate axis parallel to the aforementioned second direction at 0 degrees; the second translation error fitting unit is set to fit the measurement grid when the aforementioned substrate is adsorbed on the aforementioned substrate adsorption platform at the aforementioned 180-degree level Res_xp _180 of the second translation error: pos_xp _180= Tx _180+ xp × Sx _180- yp × Rzy _180+ Res_xp _180; where pos_xp _180 is the second actual position information of any of the aforementioned alignment measurement marks at 180 degrees The coordinate values in the two directions, Tx _180 is the translation of the entire alignment measurement mark in the first direction at 180 degrees, Sx _180 is the zoom magnification in the first direction at 180 degrees, Rzy _180 represents 180 degrees Rotation down the coordinate axis parallel to the second direction; grid translation error calculation unit, configured to calculate the alignment measurement mark of the position measurement system relative to any of the foregoing based on the first translation error and the second translation error The grid translation error of the aforementioned first direction Res_xp_ps : Res_xp_ps = ( Res_xp _0+ Res_xp _180)/2. An optical device characterized by including a grid error measuring device as described in any of items 9 to 14 of the patent application. As described in item 15 of the scope of the patent application, the aforementioned optical device includes a lithography machine.

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