Compensation method and device for focal plane of exposure machine, and exposure method

Abstract

The application provides an exposure machine focal plane compensation method and device and an exposure method, and belongs to the field of photoetching. The method comprises the following steps: obtaining a chuck height distribution map of an exposure machine by using a standard wafer measurement at intervals of several production cycles; obtaining a leveling mapping of a production wafer by scanning the production wafer through the exposure machine in a production process; comparing the chuck height distribution map with the leveling mapping of the production wafer, and selectively enabling a compensation method to compensate the focal plane of the exposure machine according to the comparison result. The method can compensate the loss of the chuck to ensure the exposure precision.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of photolithography, and particularly relates to a compensation method and device for a focus plane of an exposure machine, and an exposure method. BACKGROUND

[0002] In the process of semiconductor manufacturing, the requirement for photolithography technology is getting higher and higher with the reduction of device size.

[0003] Photolithography technology refers to a technology of exposing a photoresist layer to light through a mask by an exposure machine, and developing to obtain a patterned photoresist layer. The exposure accuracy of the exposure machine is particularly important in photolithography technology.

[0004] The Leveling Map system of the existing exposure machine has an automatic leveling function. When exposing a production wafer, the surface topography of the production wafer is scanned first. A leveling map is generated according to a preset focus plane (Focus 0 point). The exposure machine adjusts the height of the wafer in the horizontal position according to the leveling map (only the height leveling is described here, and the actual leveling function also includes the leveling of the horizontal plane) so that the high points and low points of the wafer surface fall within the depth of focus (DOF) of the exposure machine, thereby avoiding out-of-focus situations.

[0005] The stability of the exposure machine is affected by many factors. For example, the wafer is usually fixed by a chuck, and the flatness of the chuck surface will gradually change with the increase of the use frequency and cleaning frequency (such as the attachment of residues on the chuck surface). The change in the flatness of the chuck will affect the leveling of the Leveling Map system. The Leveling Map system cannot accurately monitor the wear or deformation of the chuck online to accurately determine the compensation opportunity and compensate for it, which greatly reduces the service life of the chuck. Therefore, there is an urgent need for a compensation method for the focus plane of the exposure machine to compensate for the impact of the wear of the chuck on the exposure accuracy by accurately determining the compensation opportunity. SUMMARY

[0006] Therefore, the present application provides a compensation method and device for the focus plane of an exposure machine, and an exposure method. One of the purposes is to compensate for the focus plane of the exposure machine to compensate for the poor exposure accuracy caused by the wear of the chuck. Another purpose is to apply the compensation method for the focus plane of the exposure machine to the exposure process to improve the pattern accuracy of the patterned film prepared by the exposure process.

[0007] In a first aspect, a compensation method for a focus plane of an exposure machine is provided, comprising:

[0008] The chuck height distribution of the exposure machine is obtained by measuring a standard wafer at intervals of several production cycles;

[0009] The leveling map of the production wafer is obtained by scanning the production wafer by the exposure machine during production;

[0010] The chuck height distribution and the leveling map of the production wafer are compared, and the compensation method is selectively enabled to compensate the focal plane of the exposure machine according to the comparison result.

[0011] Optionally, the step of obtaining the chuck height distribution of the exposure machine by measuring a standard wafer comprises:

[0012] The standard wafer is placed on the chuck of the exposure machine, and the surface of the standard wafer is scanned without starting the automatic leveling function to obtain the height distribution as the chuck height distribution.

[0013] Optionally, the step of obtaining the leveling map of the production wafer by scanning the production wafer by the exposure machine comprises:

[0014] The production wafer is placed on the chuck, and the production wafer is scanned after starting the automatic leveling function of the exposure machine, and the leveling map is generated according to the focal plane.

[0015] Optionally, the chuck height distribution and the production wafer height distribution are compared, and if the high point positions are the same, the compensation method is enabled to compensate the focal plane of the exposure machine.

[0016] Optionally, the step of starting the compensation method to compensate the focal plane of the exposure machine comprises:

[0017] The compensation value of the focal plane is calculated by using the Poisson curve according to the chuck height distribution.

[0018] Optionally, the compensation value of the focal plane is calculated according to the following formula:

[0019]

[0020]

[0021] In the formula, represents the compensation value of the focal plane, represents the value of the high point position, represents the value of the flat position of the wafer surface, represents the focal length of a certain position of the wafer, , , is a constant.

[0022] ​​Optionally, the height profile of the chuck is compared with the leveling map of the production wafer, and if the high point positions of the height profile of the chuck and the leveling map of the production wafer are different, the compensation method is not enabled.

[0023] In a second aspect, the present application provides a compensation device for the focal plane of an exposure machine, comprising:

[0024] A first obtaining module is configured to obtain a height profile of a chuck of the exposure machine by measuring a standard wafer at intervals of several production cycles;

[0025] A second obtaining module is configured to obtain a leveling map of a production wafer by scanning the production wafer by the exposure machine during the production process;

[0026] A compensation module is configured to compare the height profile of the chuck with the leveling map of the production wafer, and selectively enable a compensation method to compensate the focal plane of the exposure machine according to the comparison result.

[0027] Optionally, the first obtaining module is configured to:

[0028] Place the standard wafer on the chuck of the exposure machine, and scan the surface of the standard wafer without starting the automatic leveling function to obtain a height profile as the height profile of the chuck.

[0029] Optionally, the second obtaining module is configured to:

[0030] Place the production wafer on the chuck, start the automatic leveling function of the exposure machine, scan the production wafer, and generate a leveling map according to the focal plane.

[0031] Optionally, the compensation module is configured to:

[0032] Compare the height profile of the chuck with the height profile of the production wafer, and if the high point positions are the same, enable the compensation method to compensate the focal plane of the exposure machine.

[0033] Optionally, the compensation module is configured to:

[0034] According to the height profile of the chuck, a compensation value for the focal plane is calculated by using a Poisson curve.

[0035] Optionally, the compensation value calculation formula for the focal plane used by the compensation module is as follows:

[0036]

[0037]

[0038] In the formula, h represents the compensation value for the focal plane, h0 represents the height value of the high point position, and h1 represents the height value of the low point position. the value of the high point position.​​ a value representing a flat position of a wafer surface, a value, a focal length representing a certain position of a wafer, is a constant.

[0039] Optionally, the compensation module is configured to:

[0040] If the high point position of the height distribution map of the chuck is different from the high point position of the flatness mapping map of the production wafer, the compensation method is not enabled.

[0041] In a third aspect, an exposure method is provided, which comprises the compensation method of the focal plane of the exposure machine as described in any one of the above aspects.

[0042] The technical solutions provided by the present application have the following unexpected technical effects:

[0043] The present application measures the height distribution map of the chuck, and obtains the flatness mapping map of the production wafer through the scanning of the exposure machine, compares the height distribution map of the chuck with the flatness mapping map of the production wafer, and selectively enables the compensation method to compensate the focal plane of the exposure machine according to the comparison result. The unexpected technical effect is that when the chuck becomes a non-flat state due to wear and tear, the high point position of the chuck will be displayed in the height distribution map of the chuck. When the production wafer is flattened by the automatic flattening function of the exposure machine, the exposure machine will first obtain the flatness mapping map, and then adjust the wafer to the focal plane according to the flatness mapping map so that the high point and low point positions of the wafer surface are within the focal depth range. Since the flatness mapping map displays the relative distance between the wafer surface and the preset focal plane, when the wafer is fixed by the chuck in a non-flat state, the high point position in the height distribution map of the chuck will coincide with the high point position in the flatness mapping map of the exposure machine. By comparing the height distribution map of the chuck with the flatness mapping map of the exposure machine, it can be determined whether the deformation or wear of the chuck is within the automatic adjustment range of the exposure machine. If the deformation and wear of the chuck exceed the automatic adjustment range of the exposure machine, the exposure machine may not be able to move all the high point and low point positions of the wafer surface within the focal depth range of the exposure machine when adjusting the wafer by the flatness mapping map, and the compensation method needs to be enabled to compensate for the deformation and wear of the chuck. The compensation method performs additional compensation on the basis of the automatic compensation function of the exposure machine, ensures that all the high point and low point positions of the wafer surface can be moved within the focal depth range of the exposure machine, thereby ensuring the exposure accuracy of the exposure machine, and unexpectedly reducing the frequency of replacing or repairing the chuck, prolonging the service life of the chuck, and thus reducing the production cost. BRIEF DESCRIPTION OF DRAWINGS

[0044] ​​In order to more clearly illustrate the technical solutions in the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings described below are only some embodiments of the present application, and all other drawings obtained by those of ordinary skill in the art without creative effort based on these drawings belong to the protection scope of the present application.

[0045] Figure 1 A schematic diagram of a wafer leveling process by a Leveling Map system provided by the present application.

[0046] Figure 2 A schematic diagram of a wafer leveling process by another Leveling Map system provided by the present application.

[0047] Figure 3 A schematic diagram of a wafer leveling process by another Leveling Map system provided by the present application.

[0048] Figure 4 A schematic diagram of a wafer leveling process by another Leveling Map system provided by the present application.

[0049] Figure 5 A method flow chart of a compensation method for an exposure machine focal plane provided by an embodiment of the present application.

[0050] Figure 6 A schematic diagram of a wafer compensation process by a compensation method for an exposure machine focal plane provided by an embodiment of the present application.

[0051] Figure 7 A structure block diagram of a compensation device for an exposure machine focal plane provided by an embodiment of the present application.

[0052] The reference signs are as follows:

[0053] 10: a compensation device for an exposure machine focal plane; 11: a first acquisition module; 12: a second acquisition module; 13: a compensation module. DETAILED DESCRIPTION

[0054] In order to make the objects, technical solutions and advantages of the present application clearer, the following will combine the drawings in the present application to clearly and completely describe the technical solutions in the present application. Obviously, the described embodiments are only some embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort belong to the protection scope of the present application.

[0055] Figure 1This is a schematic diagram illustrating the wafer leveling process using a Leveling Map system provided in this application. See also... Figure 1 Specifically, it shows a flat chuck and a wafer fixed to the surface of the flat chuck. Figure 1 The wafer in this context is assumed to be a flat, ideally shaped production wafer, and the distance between the upper surface of the ideal wafer and the focal plane is... The Leveling Map system of the exposure machine... Figure 1 When leveling a wafer, calculations are performed first. (Distance between the lowest point on the upper surface of the wafer and the Focus 0 point) The distance between the highest point on the wafer surface and the Focus 0 point height difference This determines the average distance between the wafer and the Focus 0 point. , The Leveling Map system moves the wafer upwards. This aligns the wafer surface with the Focus0 point. Figure 1 In this context, because a wafer is a wafer with a flat surface, therefore... .

[0056] Figure 2 A schematic diagram illustrating the wafer leveling process using another Leveling Map system provided in this application. See also Figure 2 The diagram specifically illustrates a flat chuck and a non-flat wafer fixed to it. The wafer's surface is depicted as an uneven, curved surface (this is used for illustrative purposes; in actual fabrication, the wafer surface may have height differences but is not necessarily curved). It should be noted that, for ease of understanding, the diagram uses... Figure 2 Distance between the highest point of the wafer and the focal plane Set as Figure 1 In .

[0057] When the exposure machine's Leveling Map system... Figure 2 During wafer leveling, a leveling map is first generated by scanning to represent the relative height of different positions on the wafer surface. Once the relative heights of the low and high points on the wafer surface are determined... Then, determine the distance the wafer moves in the height direction. Move the height up This allows the average height of the wafer surface to be moved to the Focus 0 point, thus placing the lowest and highest points of the wafer surface within the depth of focus.

[0058] Figure 3 Another Leveling Map system provided in this application provides a schematic diagram of a wafer leveling process. Referring to FIG. 11, a non-flat chuck and a wafer originally flat but now non-flat due to being attracted to the non-flat chuck are shown. Figure 3 The actual distance between the high point of the wafer surface and the Focus 0 point Figure 1 corresponds to .

[0059] The Leveling Map system cannot identify the wafer depression caused by the chuck depression and only identifies it as a wafer surface protrusion, i.e., the Leveling Map system identifies the distance between the low point of the wafer surface and the Focus 0 point as . However, the actual distance between the high point of the wafer and the Focus 0 point is . This results in the Leveling Map system determining that the wafer needs to be moved up by a height of . Referring to FIG. 11, when the Leveling Map system levels the wafer in Figure 4 , the low point of the wafer surface cannot reach the range of the focal depth after the wafer is moved up by the height of Figure 3 . The actual wafer needs to be moved up by a height of to move the plane corresponding to the average height of the wafer surface to the Focus 0 point, . This results in a height difference between the height by which the wafer is moved up and the actual height by which the wafer should be moved up .

[0060] That is, in Figure 3 , because the wafer is depressed due to the chuck, the height by which the wafer is moved up by the Leveling Map system differs from the actual height by which the wafer should be moved up . In short, the Leveling Map system cannot identify the change in the distance between the wafer and the Focus 0 point caused by the chuck deformation, resulting in the wafer not being moved to the focal depth range of the exposure machine. If the height difference is small, the wafer will continue to be in the focal depth range of the exposure machine. If the height difference is too large, the high point or low point of the wafer surface can be out of the focal depth range, thereby affecting the exposure accuracy of the exposure machine and reducing the service life of the chuck. ​

[0061] Figure 5 The exposure machine focal plane compensation method provided by an embodiment of the present application. Referring to Figure 5 , comprising:

[0062] S101, interval several production cycles, using standard wafer measurement to get exposure machine chuck height distribution map.

[0063] In an example, step S101 includes:

[0064] The standard wafer is placed on the chuck of the exposure machine, and the surface of the standard wafer is scanned without starting the automatic leveling function to obtain the height distribution map as the chuck height distribution map.

[0065] It should be noted that the standard wafer refers to a wafer with ultra-high flatness, which is relatively thin. By fixing the standard wafer on the chuck, the height distribution map of the standard wafer obtained by the exposure machine scanning is the height distribution map of the chuck.

[0066] It should be noted that the exposure machine scans the surface of the standard wafer through the leveling sensor (Level Sensor) to obtain height data and then generates the height distribution map (i.e. "height map") of the chuck (or wafer table).

[0067] Every interval, the height distribution map of the chuck is measured again using the standard wafer, so that the wear of the chuck is updated in real time through the height distribution map of the chuck.

[0068] It should be noted that when the new height distribution map of the chuck is measured using the standard wafer, the new height distribution map is used for subsequent comparison with the leveling mapping of the production wafer and for compensation of the focal plane of the exposure machine.

[0069] In an example, the height distribution map of the chuck is measured each time, and the standard wafer is tested 1 to 25 times. By taking the average of multiple measurements or the one with smaller deviation in multiple measurements, the accuracy of the measurement can be ensured by taking the average of 25 times of testing, avoiding the interference of multiple exposure of other machine platforms / masks.

[0070] S102, in the production process, the production wafer is scanned by the exposure machine to obtain the leveling mapping of the production wafer.

[0071] In an example, step S102 includes:

[0072] The production wafer is placed on the chuck, and after starting the automatic leveling function of the exposure machine, the production wafer is scanned, and the leveling mapping is generated according to the focal plane.

[0073] The leveling map shows the relative distance of the production wafer surface to the focus plane (Focus 0 point).

[0074] In an example, the leveling map of the chuck is measured 1-25 times for the production wafer test. By measuring multiple times, taking the average of multiple measurements or the one with smaller deviation in multiple measurements can reduce measurement error and ensure the accuracy of the measurement.

[0075] S103, comparing the height distribution of the chuck with the leveling map of the production wafer, and selectively enabling the compensation method to compensate the focus plane of the exposure machine according to the comparison result.

[0076] In an example, step S103 includes:

[0077] Comparing the height distribution of the chuck with the leveling map of the production wafer, if the high point positions are the same, the compensation method is enabled to compensate the focus plane of the exposure machine.

[0078] The high point of the chuck can be understood as the "bulge" of the chuck. When the chuck is bulging, the wafer will be brought to the bulge by the chuck. If the leveling map has the "bulge" at the same position, it means that the deformation of the chuck causes the deformation of the wafer, which makes the high point or low point position of the wafer out of the depth of focus range, resulting in out-of-focus phenomenon. The wafer after leveling by the Leveling Map system of the exposure machine cannot be in the depth of focus range, and additional compensation of the focus plane of the exposure machine is needed to improve the service life of the chuck.

[0079] In an example, the compensation value of the focus plane is calculated by using Poisson curve according to the height distribution map of the chuck.

[0080] Since the out-of-focus phenomenon of the exposure machine is caused by the deformation of the chuck, the Leveling Map system of the exposure machine can automatically compensate the height distribution of the wafer, but cannot compensate the height change of the wafer and the focus plane caused by the deformation of the chuck. Therefore, by separately calculating the compensation value of the focus plane according to the height distribution map of the chuck, the height change of the wafer and the focus plane caused by the deformation of the chuck can be compensated.

[0081] In an example, the compensation value of the focus plane is calculated by using Poisson curve according to the height distribution map of the chuck.

[0082]

[0083]

[0084] In the formula, represents the compensation value of the focus plane, represents the height of the high point position, value, value, value, focus value of a certain position of the wafer, , , is constant.

[0085] wherein, the focus value according to the high point position is calculated, the focus value according to the flat position is calculated.

[0086] Referring to Figure 6 , when the compensation value of the focal plane is calculated, the wafer needs to be moved by the height calculated by the Leveling Map system of the exposure machine, and then moved by the compensation value , so that the wafer can be moved into the range of the focal depth, that is, actually moved by .

[0087] In an example, the height distribution map of the chuck is compared with the leveling map of the production wafer, and if the high point positions of the height distribution map of the chuck and the leveling map of the production wafer are different, the compensation method is not enabled.

[0088] If the high point positions of the height distribution map of the chuck and the leveling map of the production wafer are different, it indicates that the Leveling Map system of the exposure machine can move the wafer after the chuck is deformed (it is proved that the deformation is small at this time) into the focal depth range of the exposure machine.

[0089] It should be noted that the present application also provides an exposure method, which comprises the compensation method of the focal plane of the exposure machine as Figure 5 described above.

[0090] Figure 7 is a structural block diagram of the compensation device for the focal plane of the exposure machine provided by an embodiment of the present application. Referring to Figure 7 , the compensation device for the focal plane of the exposure machine 10 comprises:

[0091] a first acquisition module 11, configured to measure the chuck height distribution map of the exposure machine by using a standard wafer at intervals of several production cycles;

[0092] a second acquisition module 12, configured to obtain the leveling map of the production wafer by scanning the production wafer by the exposure machine in the production process;

[0093] The compensation module 13 is configured to compare the height distribution map of the chuck with the leveling map of the production wafer, and selectively enable the compensation method to compensate the focal plane of the exposure machine according to the comparison result.

[0094] In an example, the first obtaining module 11 is configured to:

[0095] Place a standard wafer on the chuck of the exposure machine, and scan the surface of the standard wafer without starting the automatic leveling function to obtain a height distribution map as the height distribution map of the chuck.

[0096] In an example, the second obtaining module 12 is configured to:

[0097] Place a production wafer on the chuck, start the automatic leveling function of the exposure machine, and scan the production wafer to generate a leveling map according to the focal plane.

[0098] In an example, the compensation module 13 is configured to:

[0099] Compare the height distribution of the chuck with the height distribution of the production wafer, and enable the compensation method to compensate the focal plane of the exposure machine if the high point positions are the same.

[0100] In an example, the compensation module 13 is configured to:

[0101] According to the height distribution map of the chuck, the compensation value of the focal plane is calculated by using the Poisson curve.

[0102] In an example, the compensation module 13 uses the following formula to calculate the compensation value of the focal plane:

[0103]

[0104]

[0105] In the formula, f represents the compensation value of the focal plane, h represents the value of the high point position, h0 represents the value of the flat position of the wafer surface, f0 represents the focal length of a certain position of the wafer, and k is a constant.

[0106] In an example, the compensation module 13 is configured to:

[0107] Compare the height distribution map of the chuck with the leveling map of the production wafer, and do not enable the compensation method if the high point positions of the height distribution map of the chuck and the leveling map of the production wafer are different. ​​​​​​​​​

[0108] It should be noted that the technical solutions provided by the present application have the unexpected technical effects including:

[0109] The present application measures the height distribution map of the chuck, and obtains the leveling mapping of the production wafer by scanning the exposure machine, and compares the height distribution map of the chuck with the leveling mapping of the production wafer, and selectively enables the compensation method to compensate the focal plane of the exposure machine according to the comparison result. The unexpected technical effect is that when the chuck becomes non-flat due to wear, the high point position of the chuck will be displayed in the height distribution map of the chuck. When the exposure machine automatically levels the production wafer by the automatic leveling function, the exposure machine will first obtain the leveling mapping, and then adjust the wafer to the focal plane according to the leveling mapping so that the high point and low point positions on the wafer surface are within the focal depth range. Since the leveling mapping displays the relative distance between the wafer surface and the preset focal plane, when the wafer is fixed by the chuck in a non-flat state, the high point position in the height distribution map of the chuck will coincide with the high point position in the leveling mapping of the exposure machine. By comparing the height distribution map of the chuck with the leveling mapping of the exposure machine, it can be determined whether the deformation or wear of the chuck is within the automatic adjustment range of the exposure machine. If the deformation and wear of the chuck exceed the automatic adjustment range of the exposure machine, the exposure machine may not be able to move the high point and low point positions on the wafer surface to the focal depth range of the exposure machine when leveling the wafer according to the leveling mapping, and the compensation method needs to be enabled to compensate for the deformation and wear of the chuck. By the compensation method, additional compensation is performed on the basis of the automatic compensation function of the exposure machine, so as to ensure that the high point and low point positions on the wafer surface can be moved to the focal depth range of the exposure machine, thereby ensuring the exposure accuracy of the exposure machine.

[0110] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method of compensating for a focal plane of an exposure machine, characterized in that, The method comprises the following steps: At intervals of several production cycles, a chuck height distribution map of the exposure machine is obtained by measuring a standard wafer, specifically comprising the following steps: The standard wafer is placed on the chuck of the exposure machine, and the surface of the standard wafer is scanned without starting the automatic leveling function to obtain a height distribution map as the chuck height distribution map; During the production process, the production wafer is scanned by the exposure machine to obtain a leveling mapping map of the production wafer, specifically comprising the following steps: The production wafer is placed on the chuck, and the production wafer is scanned after starting the automatic leveling function of the exposure machine, and a leveling mapping map is generated according to the focal plane; The chuck height distribution map and the leveling mapping map of the production wafer are compared, and the compensation method is selectively enabled according to the comparison result to compensate the focal plane of the exposure machine, specifically comprising the following steps: If the high point positions of the chuck height distribution map and the leveling mapping map of the production wafer are the same, the compensation method is enabled to compensate the focal plane of the exposure machine.

2. The method of compensating for the focal plane of an exposure machine according to claim 1, wherein, The step of starting the compensation method to compensate the focal plane of the exposure machine comprises the following steps: According to the chuck height distribution map, the compensation value of the focal plane is calculated by using the Poisson curve.

3. The method of compensating for the focal plane of an exposure tool according to claim 1, wherein, If the high point positions of the chuck height distribution map and the leveling mapping map of the production wafer are different, the compensation method is not enabled.

4. A compensator for the focal plane of an exposure machine, characterized in that The method comprises the following steps: The first acquisition module is used for obtaining the chuck height distribution map of the exposure machine by measuring the standard wafer at intervals of several production cycles, specifically comprising the following steps: The standard wafer is placed on the chuck of the exposure machine, and the surface of the standard wafer is scanned without starting the automatic leveling function to obtain a height distribution map as the chuck height distribution map; The second acquisition module is used for obtaining the leveling mapping map of the production wafer by scanning the production wafer by the exposure machine during the production process, specifically comprising the following steps: The production wafer is placed on the chuck, and the production wafer is scanned after starting the automatic leveling function of the exposure machine, and a leveling mapping map is generated according to the focal plane; The compensation module is used for comparing the chuck height distribution map and the leveling mapping map of the production wafer, and selectively enabling the compensation method to compensate the focal plane of the exposure machine according to the comparison result, specifically comprising the following steps: If the high point positions of the chuck height distribution and the height distribution of the production wafer are the same, the compensation method is enabled to compensate the focal plane of the exposure machine.

5. The compensation device for the focal plane of the exposure machine according to claim 4, characterized in that, The compensation module is used for: According to the chuck height distribution map, the compensation value of the focal plane is calculated by using the Poisson curve.

6. The compensation device for focal plane of exposure machine according to claim 4, characterized in that, The compensation module is used for: If the high point positions of the chuck height distribution map and the leveling mapping map of the production wafer are different, the compensation method is not enabled.

7. An exposure method characterized by, The method comprises the following steps: The method comprises the following steps: The method comprises the following steps:

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