Reticle deformation correction method, system, lithography machine, device, medium and program

Abstract

Embodiments of the present application provide a mask deformation correction method, system, photolithography machine, device, medium and program, wherein the mask deformation correction method comprises: obtaining deformation information of a mask; determining a deformation correction amount corresponding to the deformation information of the mask according to the deformation information of the mask; and generating a corresponding control electrical signal according to the deformation correction amount, the control electrical signal being used to control a driving force for adjusting the attitude of the mask to correct the deformation of the mask. By using the above technical solution, the deformation of the mask can be corrected, thereby reducing the deformation of the mask and improving the photolithography precision.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor manufacturing technology, and in particular to a method, system, lithography machine, equipment, medium and program for correcting photomask deformation. Background Technology

[0002] In semiconductor manufacturing, photolithography is a key technology for pattern transfer, and its control precision and resolution directly determine the yield of semiconductors.

[0003] During the exposure process of photolithography, the pattern on the photomask is mapped onto the photoresist. Then, through a series of processes, the pattern on the photoresist is preserved, thus realizing the pattern transfer from the photomask to the wafer.

[0004] During the pattern transfer process, the photomask will deform due to the irradiation of high-power light, resulting in a large overlay error in the final pattern and low photolithography accuracy.

[0005] Against this backdrop, how to provide technical solutions to reduce the deformation of photomasks has become a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0006] In view of this, embodiments of the present invention provide a method, system, lithography machine, device, medium, and program for correcting photomask deformation, which can correct the deformation of the photomask, thereby reducing the deformation of the photomask and improving the lithography accuracy.

[0007] This invention provides a method for correcting photomask deformation, comprising:

[0008] Obtain deformation information of the photomask;

[0009] Based on the deformation information of the photomask, determine the deformation correction amount corresponding to the deformation information of the photomask;

[0010] Based on the deformation correction amount, a corresponding control electrical signal is generated. The control electrical signal is used to control the generation of a driving force to adjust the attitude of the photomask, so as to correct the deformation of the photomask.

[0011] Optionally, the photomask includes multiple regions, and the deformation information includes: at least one deformed region of the photomask where deformation exists, and the deformation amount of each deformed region;

[0012] The step of determining the deformation correction amount corresponding to the deformation information of the photomask based on the deformation information of the photomask includes:

[0013] Based on the pre-set mapping relationship between deformation and deformation correction, the deformation correction amount mapped to the deformation of each deformation region is determined.

[0014] Optionally, the deformation correction includes a displacement correction.

[0015] Optionally, generating a corresponding control electrical signal based on the deformation correction amount, the control electrical signal being used to control the generation of a driving force to adjust the attitude of the photomask, so as to correct the deformation of the photomask, includes:

[0016] The required driving voltage value for each deformation region is determined based on the deformation correction amount for each deformation region.

[0017] Based on the required driving voltage value for each deformation region, a control electrical signal corresponding to each deformation region is generated.

[0018] In this process, a control electrical signal corresponding to a deformation region is used to control the generation of a driving force corresponding to the driving voltage value of the deformation region, so that the photomask moves in the driving direction of the driving force to correct the deformation of the deformation region.

[0019] Optionally, obtaining the deformation information of the photomask includes:

[0020] The deviation regions with positional deviations among multiple regions of the photomask are identified and designated as the deformation regions;

[0021] The deformation amount of each deformation region is determined based on the positional deviation of each deformation region.

[0022] Optionally, each region of the photomask is provided with a position marker;

[0023] The determination of the deviation regions, which are among the multiple regions of the photomask where positional deviations exist, includes:

[0024] Before or after executing any exposure process, obtain the actual position information of the light source illuminating the wafer through the position markers of each region;

[0025] Based on the actual position information and the set position information of the light source illuminating the wafer through the position markers of each region, the deviation regions with positional deviations are determined among the multiple regions.

[0026] Optionally, obtaining the deformation information of the photomask includes:

[0027] Obtain pre-stored deformation information of the photomask corresponding to each exposure process. The deformation information includes: the deformation region of the photomask corresponding to each exposure process, and the deformation amount of the deformation region.

[0028] This invention also provides a photomask deformation correction system, comprising:

[0029] Deformation information acquisition unit, suitable for acquiring the deformation of the photomask;

[0030] The deformation correction control unit is adapted to determine the deformation correction amount corresponding to the deformation information of the photomask based on the deformation information of the photomask, and to generate a corresponding control electrical signal based on the deformation correction amount;

[0031] The deformation correction unit is adapted to generate a driving force for adjusting the orientation of the photomask according to the control electrical signal, so as to correct the deformation of the photomask.

[0032] Optionally, the photomask includes multiple regions, and the deformation information includes: at least one deformed region of the photomask where deformation exists, and the deformation amount of each deformed region;

[0033] The deformation correction control unit includes:

[0034] The deformation correction calculation module is suitable for determining the deformation correction amount mapped to the deformation amount of each deformation region according to the pre-set mapping relationship between the deformation amount and the deformation correction amount.

[0035] The deformation correction control module is adapted to determine the required driving voltage value for each deformation region based on the deformation correction amount of each deformation region, and to generate the corresponding control electrical signal for each deformation region based on the required driving voltage value of each deformation region.

[0036] In this process, a control electrical signal corresponding to a deformation region is used to control the generation of a driving force corresponding to the driving voltage value of the deformation region, so that the photomask moves in the driving direction of the driving force to correct the deformation of the deformation region.

[0037] Optionally, the deformation correction unit includes: a plurality of piezoelectric ceramics, the plurality of piezoelectric ceramics being arranged along the circumference of the photomask, and at least one piezoelectric ceramic corresponding to a region on the photomask.

[0038] This invention also provides a lithography machine, comprising:

[0039] Photomask;

[0040] The photomask deformation correction system described in any of the foregoing examples is suitable for correcting the deformation of the photomask.

[0041] This invention also provides a data processing device, including a memory and a processor, wherein the memory is adapted to store one or more computer instructions, and the processor executes the photomask deformation correction method described in any of the foregoing examples when running the computer instructions.

[0042] This invention also provides a computer-readable storage medium storing computer instructions, which, when executed, perform the photomask deformation correction method described in any of the foregoing examples.

[0043] This invention also provides a computer program product, characterized in that it includes computer instructions, which, when executed by a processor, implement the photomask deformation correction method described in any of the foregoing examples.

[0044] The photomask deformation correction method provided in this invention determines the deformation correction amount based on the obtained photomask deformation information. Since the deformation information reflects the degree of photomask deformation, a control electrical signal is generated based on the deformation correction amount to control the generation of a driving force that adjusts the photomask's orientation. This control electrical signal controls the generation of the driving force that adjusts the photomask's orientation to correct the photomask deformation. In other words, under the control of the control electrical signal, by applying a driving force to the photomask, the orientation of the photomask can be adjusted to offset or reduce the photomask deformation, thereby correcting the photomask deformation, reducing the deformation, and ultimately improving lithography accuracy. Attached Figure Description

[0045] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments of the present invention or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0046] Figure 1 This is a flowchart of a photomask deformation correction method according to an embodiment of the present invention;

[0047] Figure 2 This is a flowchart illustrating how to obtain deformation information of a photomask in an embodiment of the present invention;

[0048] Figure 3 This is a flowchart of a photomask deformation correction method in a specific example of an embodiment of the present invention;

[0049] Figure 4 This is a schematic diagram of the structure of a photomask deformation correction system according to an embodiment of the present invention;

[0050] Figure 5 This is a schematic diagram of the structure of a photomask deformation correction system in a specific application scenario of this invention. Detailed Implementation

[0051] As described in the background art, during the exposure process of photolithography, the photomask will deform due to the irradiation of high-power light, resulting in a large overlay error in the pattern formed on the wafer and low photolithography accuracy.

[0052] To address the aforementioned technical problems, this invention provides a method for correcting photomask deformation. Based on the obtained deformation information of the photomask, a deformation correction amount corresponding to the deformation information can be determined. Since the deformation information reflects the degree of photomask deformation, a control electrical signal can be generated based on the deformation correction amount to control the generation of a driving force that adjusts the orientation of the photomask. This control electrical signal is used to control the generation of the driving force that adjusts the orientation of the photomask, thereby correcting the deformation of the photomask. In other words, under the control of the control electrical signal, by applying a driving force to the photomask, the orientation of the photomask can be adjusted to offset or reduce the deformation of the photomask, thus correcting the deformation and improving the lithography accuracy.

[0053] To enable those skilled in the art to have a clearer understanding of the technical concepts, principles, advantages, etc. contained in the embodiments of the present invention, the following description is provided with reference to the accompanying drawings, through specific embodiments, and in conjunction with specific application scenarios.

[0054] See Figure 1 The flowchart shown in this embodiment of the invention illustrates a method for correcting photomask deformation. In some embodiments, the deformation of the photomask can be corrected according to the following steps:

[0055] S11, obtain the deformation information of the photomask.

[0056] Specifically, by acquiring the deformation information of the photomask, the deformation state of the photomask can be confirmed, and then the corresponding correction scheme can be determined based on the deformation information of the photomask.

[0057] In some embodiments, the photomask may include multiple regions.

[0058] Accordingly, the deformation information of the photomask may include: at least one deformed region of the photomask, and the deformation amount of each deformed region. That is, in the step of obtaining the deformation information of the photomask, if the photomask is deformed, the deformed region of the photomask and the deformation amount corresponding to the deformed region can be determined through the deformation information of the photomask.

[0059] S12, Based on the deformation information of the photomask, determine the deformation correction amount corresponding to the deformation information of the photomask.

[0060] Specifically, the deformation information of the photomask can reflect the current deformation state of the photomask (e.g., the deformed area and the deformation amount of the deformed area). Therefore, based on the deformation information of the photomask, the deformation correction amount corresponding to the deformation information of the photomask can be obtained, so as to correct the deformation of the photomask that has occurred.

[0061] In some embodiments, the deformation amount can reflect the degree of curvature of the deformed area when the photomask deforms; the deformation correction amount can reflect the displacement value required to move the deformed area in order to restore the deformed area to its original state. The larger the deformation amount, the greater the degree of curvature of the deformed area, and thus the greater the deformation correction amount required to restore the deformed area to its original state.

[0062] S13, Generate a corresponding control electrical signal based on the deformation correction amount.

[0063] Specifically, the deformation correction amount is the displacement value that needs to drive the deformation area to move in order to restore the deformation area to its original state. By generating a control electrical signal corresponding to the deformation correction amount, the deformation area can move according to the displacement value corresponding to the deformation correction amount, thereby correcting the deformation of the photomask.

[0064] In some embodiments, a driving force for adjusting the orientation of the photomask can be generated based on a control electrical signal. That is, by applying a driving force to the photomask, the orientation of the photomask can be adjusted to counteract or reduce the deformation of the photomask, thereby correcting the deformation of the photomask so that the orientation of the photomask tends to a preset orientation (e.g., the orientation of the photomask when it is not deformed).

[0065] In some examples, based on control electrical signals, the deformation of the photomask can be specifically corrected in multiple different regions.

[0066] As can be seen from the above deformation correction process, deformation information can reflect the degree of deformation of the photomask. Based on the deformation correction amount, a control electrical signal can be generated to control the generation of a driving force that adjusts the orientation of the photomask. This control electrical signal is used to control the generation of the driving force that adjusts the orientation of the photomask, thereby correcting the deformation of the photomask. In other words, under the control of the control electrical signal, by applying a driving force to the photomask, the orientation of the photomask can be adjusted to counteract or reduce the deformation of the photomask, thus correcting the deformation of the photomask. This, in turn, can reduce the overlay error of the formed pattern and improve the lithography accuracy.

[0067] To enable those skilled in the art to better understand and implement the photomask deformation correction method in the embodiments of the present invention, the following description is provided through specific examples and in conjunction with the accompanying drawings.

[0068] In some embodiments, for a photomask with multiple regions, each region on the photomask may be deformed. Therefore, it is necessary to determine the deformed regions on the photomask and the deformation amount of the deformed regions, so that the deformed regions can be corrected.

[0069] See in some examples Figure 2 The flowchart shown in this embodiment of the invention illustrates a process for obtaining deformation information of a photomask, as follows: Figure 2 As shown, the following steps can be performed:

[0070] S21, determine the deviation regions with positional deviations in multiple regions of the photomask, and use them as the deformation regions.

[0071] Specifically, during the exposure stage of the photolithography process, when transferring the pattern to the wafer, the light source illuminates the wafer through the photomask. According to the photolithography principle, the position of the light illuminating the wafer through the photomask should be the same as the set position information, that is, the position of the pattern transferred to the wafer through the photomask should be the same as the preset pattern position.

[0072] During the exposure stage of the photolithography process, the relative position of the wafer is relatively fixed. When the position of the light source shining on the wafer through the photomask shifts, the position of the pattern transferred to the wafer will also shift. Therefore, by obtaining the position of the light source shining on the wafer through the photomask, the deviation areas with positional deviations in multiple regions on the photomask can be determined.

[0073] In other words, when the position of the light source shining on the wafer through the photomask is the same as the set position information, it means that the photomask has not been deformed; when the position of the light source shining on the wafer through the photomask is different from the set position information, it means that there is at least one deformed area on the photomask. Therefore, the area on the wafer where the light source shines on it and is offset can be regarded as the deformed area on the photomask.

[0074] S22, determine the deformation amount of each deformation region based on the positional deviation of each deformation region.

[0075] Specifically, to identify the deviation areas where positional deviations exist, the positional deviation of each deformation area can be determined based on the difference between the actual position of the light source illuminating the wafer and the set position. Then, based on the positional deviation of each deformation area, the deformation amount of each deformation area can be determined.

[0076] By determining in real time the deviation areas with positional deviations in multiple regions of the photomask, as well as the deformation of each deformation area, and improving the accuracy of the deformation of the deformation area, the deformation area can be accurately corrected when it is corrected, and the correction difficulty can be reduced.

[0077] In some embodiments, to facilitate determining the position of the light source illuminating the wafer through the photomask, position markers are provided in each area of ​​the photomask. By determining the position of the light source illuminating the wafer through each position marker, the deformation area on the photomask can be determined.

[0078] In some examples, step S21 may include:

[0079] Before or after executing any exposure process, the actual position information of the light source illuminating the wafer through the position markers of each region is obtained; based on the actual position information of the light source illuminating the wafer through the position markers of each region and the set position information, the deviation regions with positional deviations are determined among the multiple regions.

[0080] Specifically, by comparing the actual position information of the light source illuminating the wafer through the position markers of each region with the set position information, the deviation area with positional deviation can be determined, that is, the area on the photomask that has been deformed. Then, based on the difference between the actual position information of the light source illuminating the wafer through the position markers of each region and the set position information, the deformation amount of each deformed area can be determined.

[0081] Furthermore, by comparing the actual position information of the light source illuminating the wafer through the position markers of each region with the set position information before executing the exposure process, it is possible to determine whether there is a deviation area of ​​positional deviation of the photomask before executing the exposure process, and thus determine the area where the photomask is deformed, so as to reduce the impact of the photomask on the first exposure process; and by comparing the actual position information of the light source illuminating the wafer through the position markers of each region with the set position information after executing any exposure process, it is possible to determine whether there is a deviation area of ​​positional deviation of the photomask after any exposure process, and thus determine the deformation area of ​​the photomask and make timely corrections, so as to reduce the impact of the photomask on subsequent exposure processes.

[0082] In other words, by identifying the deformed areas on the photomask before or after the exposure process, the deformed photomask can be corrected in a timely manner to reduce its impact on subsequent exposure processes and improve the quality of the pattern formed by the photolithography process.

[0083] In some embodiments, a position sensor on the wafer carrier can be used to obtain the actual position information of the light source illuminating the wafer through the position markers of each area.

[0084] Specifically, the wafer is placed on a wafer carrier platform. By measuring the position of the wafer carrier platform, the actual position information of the light source illuminating the wafer through the position markers in each area can be obtained. In this case, by setting a position sensor on the wafer carrier platform, the position of the light source illuminating the wafer through the position markers in each area detected by the position sensor is the actual position information of the light source illuminating the wafer.

[0085] In some embodiments, based on the actual position information and the set position information of the light source illuminating the wafer through the position marks of each region, the position deviation of the light source illuminating the wafer through the position marks of each region in the current state can be determined. Then, based on the position deviation, the shape change of the position marks of each region on the photomask relative to the photomask when it is not deformed can be determined, so as to obtain the deformation of each deformed region.

[0086] In some embodiments, the light source irradiates the wafer through the position marks of each region at a certain value (this value is generally the factory setting value). When the photomask is deformed, the position marks of each region will shift relative to the initial position, and the vector corresponding to this shift is the deformation amount of each deformed region.

[0087] In some embodiments, the same photomask is typically used multiple times to expose different batches of wafers. For example, a batch typically consists of 25 wafers, and a single photomask is used to expose all 25 wafers from different batches.

[0088] In actual exposure processing, the inventors discovered that for the same photomask, when different batches of wafers are exposed, the deformation area of ​​the photomask and the deformation amount of the deformation area are the same or tend to be the same. For example, for the exposure process of wafers in batch 1 and batch 2, after the first exposure of the wafers using the same photomask, the deformation area of ​​the photomask in batch 1 and batch 2, as well as the deformation amount of the deformation area, are the same or tend to be the same.

[0089] In some examples, during the historical exposure process using a photomask, the deformation information of the photomask when exposing different batches of wafers can be stored. Then, when it is necessary to determine the deformation information of the photomask, the pre-stored deformation information of the photomask corresponding to each exposure process can be obtained.

[0090] For example, it is possible to obtain the deformation regions of the photomask corresponding to each exposure process, as well as the deformation amount of the deformation regions.

[0091] By directly acquiring the pre-stored deformation information of the photomask corresponding to each exposure process, the time required for photomask deformation correction can be reduced, thereby improving lithography efficiency.

[0092] In some embodiments, when a deformed region on the photomask and the deformation amount of the deformed region are obtained, a deformation correction amount corresponding to the deformation amount of the deformed region can be determined to correct the deformation amount of the deformed region.

[0093] In some examples, the deformation correction amount mapped to the deformation of each deformation region can be determined according to the pre-set mapping relationship between deformation and deformation correction amount.

[0094] As mentioned earlier, deformation can reflect the degree of curvature of the deformed area when the photomask deforms, while deformation correction can reflect the displacement value required to move the deformed area to restore it to its original state. By changing the deformation correction applied to the photomask, the displacement value of different areas on the photomask can be changed, thereby obtaining the attitude (i.e. deformation) of the photomask under different deformation correction values. Based on multiple corresponding deformation correction values ​​and photomask attitudes, the mapping relationship between deformation and deformation correction can be determined.

[0095] In some examples, when the deformation region on the photomask and the deformation amount of the deformation region are determined using the methods described above, the required deformation correction amount for the deformation region can be determined based on the deformation amount. That is, the required deformation correction amount for the deformation region can be automatically obtained according to the mapping relationship between the deformation amount and the deformation correction amount, without manual processing, which can improve the computational efficiency and the accuracy of the calculated deformation correction amount.

[0096] In some examples, the mapping relationship between deformation and deformation correction can be:

[0097]

[0098] Where, ΔY n The vector represents the deformation of the photomask, 'a' represents a constant term, 'n' represents the position of the deformation correction unit on the deformed region of the photomask, and 'ΔX' represents the deformation of the photomask. n R represents the control electrical signal output to the deformation correction unit on the deformed area of ​​the photomask, and R represents the remainder.

[0099] It should be noted that a and R are parameters set to correct deformation variables. In practice, the values ​​of a and R can be adjusted according to the fitting process.

[0100] In some embodiments, the presence of deformed regions on the photomask indicates a change in the overall flatness of the photomask surface, and a change in the morphology of at least one region on the photomask relative to other regions on the photomask (e.g., a region becomes bent). Therefore, by restoring the deformed region to its original state, the photomask deformation can be corrected to improve the lithography accuracy.

[0101] In some examples, the deformation correction includes a displacement correction. For any deformed region, the displacement correction can be expressed as the displacement value that the deformed region needs to move to compensate for the deformation. Therefore, based on the displacement correction of the deformed region of the photomask, the deformed region on the photomask can move according to the displacement value corresponding to the displacement correction, thereby achieving precise local correction and the desired correction effect.

[0102] In some embodiments, after determining the displacement correction amount corresponding to the deformation of the deformation region, the driving force applied to the deformation region can be determined to change the orientation of the deformation region.

[0103] See in some examples Figure 3 The flowchart of the photomask deformation correction method in a specific example of an embodiment of the present invention shown can be implemented with the following steps:

[0104] S31, determine the required driving voltage value for each deformation region based on the deformation correction amount of each deformation region.

[0105] Specifically, the degree of deformation of different deformation regions on the photomask is different, and the corresponding deformation correction amount is also different. When correcting the deformation of the deformation region, the required driving voltage value is also different. Therefore, the required driving voltage value of each deformation region can be determined according to the deformation correction amount of each deformation region.

[0106] In some embodiments, the deformation correction amount may include a displacement correction amount, i.e., the displacement value that the deformed region needs to move. The displacement value that the deformed region needs to move can be converted into a voltage value. By applying a voltage value to a device or apparatus used to drive the deformed region on the photomask to move, the device or apparatus can be made to expand or shrink, thereby realizing the movement of the deformed region. In this embodiment of the invention, "device or apparatus" refers to an element that has a voltage value converted into a displacement value (i.e., piezoelectric effect).

[0107] That is, through the piezoelectric effect, the deformation correction amount of each deformation region can be converted into the driving voltage value required by each deformation region.

[0108] S32 generates control electrical signals corresponding to each deformation region based on the required driving voltage value for each deformation region.

[0109] In some embodiments, a control electrical signal corresponding to a deformed region is used to control the generation of a driving force corresponding to the driving voltage value of the deformed region, so that the photomask moves in the driving direction of the driving force to correct the deformation of the deformed region.

[0110] Specifically, the driving voltage value is determined by the deformation correction amount, which may include a displacement correction amount representing the displacement value that the deformed area needs to move. Then, according to the control electrical signal, the required driving force can be provided to each deformed area to drive the photomask to move in the direction of the driving force (for example, to drive the deformed area of ​​the photomask to move by a corresponding displacement value in the direction of the driving force), thereby correcting the deformation of the deformed area.

[0111] In some embodiments, multiple devices or equipment can be configured on the photomask to drive different deformation regions on the photomask to move. When a deformation region exists, a control electrical signal is applied to the device or equipment disposed in the deformation region, so that the device or equipment in the deformation region generates a corresponding driving force based on the control electrical signal to drive the deformation region to move (e.g., drive the deformation region to move by a corresponding displacement value), thereby changing the deformation state of the deformation region and correcting the deformation region.

[0112] In some examples, the deformation of the deformed region can be corrected by applying a force to a region of the photomask along its surface direction. That is, after determining the deformed region on the photomask, the deformation of the deformed region can be corrected by applying a force along the surface direction of the photomask.

[0113] This invention also provides a photomask deformation correction system corresponding to the aforementioned photomask deformation correction method. The following description is based on specific examples and refers to the accompanying drawings.

[0114] Reference Figure 4 The diagram shown is a structural schematic of a photomask deformation correction system according to an embodiment of the present invention. Figure 4 As shown, in some embodiments, the photomask deformation correction system 100 may include a deformation information acquisition unit 110, a deformation correction control unit 120, and a deformation correction unit 130, wherein:

[0115] The deformation information acquisition unit 110 is adapted to acquire the deformation of the photomask;

[0116] The deformation correction control unit 120 is adapted to determine the deformation correction amount corresponding to the deformation information of the photomask based on the deformation information of the photomask, and to generate a corresponding control electrical signal based on the deformation correction amount.

[0117] The deformation correction unit 130 is adapted to generate a driving force for adjusting the attitude of the photomask according to the control electrical signal, so as to correct the deformation of the photomask.

[0118] The following combination Figure 4 A brief introduction to the working principle of the photomask deformation correction system 100:

[0119] The deformation information acquisition unit 110 can acquire the deformation of the photomask. Then, the deformation correction control unit 120 can determine the deformation correction amount corresponding to the deformation information of the photomask when the photomask is deformed, and generate a control electrical signal corresponding to the deformation correction amount to the deformation correction unit 130. Since the deformation information can reflect the degree of deformation of the photomask, the deformation correction unit 130 can generate a driving force for adjusting the attitude of the photomask to correct the deformation of the photomask.

[0120] That is, by applying a driving force to the photomask through the deformation correction unit 130, the orientation of the photomask can be adjusted to offset or reduce the deformation of the photomask, thereby correcting the deformation of the photomask, reducing the deformation of the photomask, and thus improving the lithography accuracy.

[0121] In some embodiments, for a photomask with multiple regions, each region on the photomask may be deformed. Therefore, it is necessary to determine the deformed regions on the photomask and the corresponding deformation amounts, so that the deformed regions can be corrected.

[0122] In some examples, the deformation information acquisition unit can identify the deviation regions with positional deviations in multiple regions of the photomask and use them as deformation regions. Then, based on the positional deviations of each deformation region, the deformation amount of each deformation region can be determined.

[0123] The process by which the deformation information acquisition unit determines the deformation region and the deformation amount of each deformation region can be found in the aforementioned example.

[0124] In some embodiments, when a deformed region on the photomask is determined, and the deformation amount of the deformed region is determined, a deformation correction amount corresponding to the deformation amount of the deformed region can be determined to correct the deformation amount of the deformed region.

[0125] In some examples, see next. Figure 4 The deformation correction control unit 120 may include: a deformation correction amount calculation module 121 and a deformation correction control module 122, wherein:

[0126] The deformation correction calculation module 121 is adapted to determine the deformation correction amount mapped to the deformation amount of each deformation region according to the pre-set mapping relationship between the deformation amount and the deformation correction amount.

[0127] The deformation correction control module 122 is adapted to determine the required driving voltage value for each deformation region based on the deformation correction amount of each deformation region, and to generate the corresponding control electrical signal for each deformation region based on the required driving voltage value of each deformation region.

[0128] Specifically, when the deformation region on the photomask and the deformation amount of the deformation region are determined, the deformation correction calculation module 121 can determine the required deformation correction amount for the deformation region based on the deformation amount. That is, the required deformation correction amount for the deformation region can be automatically obtained according to the mapping relationship between the deformation amount and the deformation correction amount, without manual processing, which can improve the calculation efficiency and the accuracy of the calculated deformation correction amount; then, the deformation correction control module 122 can determine the required driving voltage value for each deformation region according to the deformation correction amount of each deformation region.

[0129] In some examples, a control electrical signal corresponding to a deformed region is used to control the generation of a driving force corresponding to the driving voltage value of the deformed region, so that the photomask moves in the driving direction of the driving force to correct the deformation of the deformed region.

[0130] Specifically, the driving voltage value determined by the deformation correction control module 122 is determined by the deformation correction amount, which may include a displacement correction amount representing the displacement value that the deformation region needs to move. Then, the deformation correction control module 122 generates a control electrical signal for controlling the driving force required to provide each deformation region, so as to correct the deformation of the deformation region.

[0131] In some examples, the deformation correction control module 122 can be implemented by a processing chip such as a central processing unit (CPU) or a field programmable gate array (FPGA), or by an application specific integrated circuit (ASIC) or one or more integrated circuits configured to implement embodiments of the present invention.

[0132] In some embodiments, a control electrical signal corresponding to a deformed region is used to control the generation of a driving force corresponding to the driving voltage value of the deformed region. That is, the control electrical signal is determined according to the deformation of the deformed region on the photomask, so the deformed region can be corrected.

[0133] In some examples, the deformation correction unit may include multiple piezoelectric ceramics arranged circumferentially along the photomask.

[0134] In some examples, a region on the photomask corresponds to at least one piezoelectric ceramic. That is, when a deformable region is determined to exist on the photomask, a control electrical signal can be applied to the piezoelectric ceramic located in that region to move the deformable region and change its deformation state. In some examples, the piezoelectric ceramic can correct the deformation of the deformable region by applying a force to a region of the photomask along its surface direction.

[0135] To enable those skilled in the art to better understand and implement the photomask deformation correction scheme in the embodiments of the present invention, the following description uses a specific application scenario as an example.

[0136] Combination Figure 4 , refer to Figure 5 The diagram shown is a structural schematic of a photomask deformation correction system in a specific application scenario of an embodiment of the present invention. Figure 5 As shown, the photomask deformation correction system 100 includes a deformation information acquisition unit ( Figure 5 (not shown), deformation correction control unit 120, and deformation correction unit ( Figure 5 (Unmarked).

[0137] In some examples, the deformation correction unit includes a plurality of piezoelectric ceramics arranged circumferentially along the photomask 10A, and a region on the photomask 10A corresponds to at least one piezoelectric ceramic.

[0138] As a specific example, see Figure 5 One of the piezoelectric ceramics P is shown in the diagram, and the piezoelectric ceramic P can be electrically connected to the deformation correction control unit 120.

[0139] In some embodiments, when the deformation information acquisition unit acquires the deformation regions on the photomask 10A and the deformation amount of each deformation region, the deformation correction control unit 120 can generate a control electrical signal for controlling the movement of the deformation regions and output the control electrical signal to the piezoelectric ceramic P disposed in the deformation region. Based on the control electrical signal, the piezoelectric ceramic P corresponding to the deformation region can be driven to expand or compress. When the driving voltage value of the control electrical signal changes in a positive direction (from small to large), the piezoelectric ceramic P can expand (i.e., elongate) so that the deformation region moves towards the center region of the photomask. When the driving voltage value of the control electrical signal changes in a negative direction (from large to small), the piezoelectric ceramic P can compress so that the deformation region moves away from the center region of the photomask, thereby changing the orientation of the photomask corresponding to the deformation region and thus correcting the deformation of the photomask.

[0140] It should be noted that, firstly, the distribution of piezoelectric ceramic P on the photomask 10A is merely an illustrative example, used to illustrate that piezoelectric ceramic P for changing the orientation of the photomask 10A can be arranged circumferentially on the photomask 10A, and should not be construed as a limitation of the present invention; secondly, Figure 5 The diagram only illustrates the electrical connection between one piezoelectric ceramic P and the deformation correction control unit 120. In practical applications, the deformation correction control unit 120 can be electrically connected to all piezoelectric ceramics P.

[0141] This invention also provides a lithography machine. In some embodiments, the lithography machine may include a photomask and a photomask deformation correction system as described in any of the above embodiments. The photomask deformation correction system is adapted to correct the deformation of the photomask.

[0142] Specifically, when transferring the pattern on the photomask to the wafer surface, the photomask deformation correction system can correct the deformation of the photomask to reduce the impact of the photomask on the exposure process.

[0143] In some examples, see next. Figure 5 The lithography machine may also include a photomask stage ZT, which is used to support the photomask 10A.

[0144] In some implementations, a vacuum chuck is also provided between the photomask 10A and the photomask stage ZT. The vacuum chuck can create a vacuum environment between the photomask 10A and the photomask stage ZT, so that the photomask 10A is tightly adsorbed on the photomask stage ZT, preventing the photomask 10A from falling off the photomask stage ZT, thereby improving the stability during the exposure process.

[0145] In some embodiments, the present invention provides a data processing device, which may include a memory and a processor, and the memory and the processor may communicate with each other via a communication bus; the memory stores one or more computer instructions that can be executed on the processor, and when the processor executes the computer instructions, it can execute the photomask deformation correction method described in any of the above embodiments, and the details can be referred to the above related content, which will not be repeated here.

[0146] In some examples, the processor may include a central processing unit (CPU) piezoelectric ceramic CPU, a field-programmable gate array (FPGA), etc. The memory may include random access memory (RAM), read-only memory (ROM), non-volatile memory (NVM), etc.

[0147] In some examples, computer instructions may include any suitable type of code implemented using any appropriate high-level, low-level, object-oriented, visual, compiled, and / or interpreted programming language, such as source code, compiled code, interpreted code, executable code, static code, dynamic code, encrypted code, etc.

[0148] In some examples, the data processing device may further include a display interface and a display connected via the display interface. The display interface can communicate with a memory and a processor via a communication bus. The display can display the correction data obtained by the processor executing the photomask deformation correction method provided in the embodiments of the present invention.

[0149] In some embodiments, the data processing device may further include a data output interface. The data output interface can communicate with the memory and processor via a communication bus to output various data during the shield deformation correction process.

[0150] The present invention also provides a computer-readable storage medium storing computer instructions thereon, which, when executed, can perform the photomask deformation correction method described in any of the above embodiments of the present invention. For details, please refer to the above-mentioned related content, which will not be repeated here.

[0151] Computer-readable storage media can include any suitable type of memory cell, memory device, memory article, memory medium, storage device, storage article, storage medium, and / or storage cell. Examples include memory, removable or non-removable media, erasable or non-erasable media, writable or rewritable media, digital or analog media, hard disk, floppy disk, optical disc read-only memory (CD-ROM), recordable optical disc (CD-R), rewritable optical disc (CD-RW), optical disc, magnetic media, magneto-optical media, removable memory cards or disks, various types of digital versatile optical discs (DVDs), magnetic tape, cassette tape, etc. Furthermore, computer instructions can include any suitable type of code implemented using any suitable high-level, low-level, object-oriented, visual, compiled, and / or interpreted programming language, such as source code, compiled code, interpreted code, executable code, static code, dynamic code, encrypted code, etc.

[0152] The present invention also provides a computer program product, which may include computer instructions. When the computer instructions are executed by a processor, they implement the photomask deformation correction method described in any of the above embodiments of the present invention. For details, please refer to the above-mentioned related content, which will not be repeated here.

[0153] While this specification discloses the invention as described above, the invention is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the invention; therefore, the scope of protection of this invention should be determined by the scope defined in the claims.

Claims

1. A method for correcting photomask deformation, characterized in that, include: Obtain deformation information of a photomask, wherein the photomask includes multiple regions, and the deformation information includes: at least one deformation region of the photomask where deformation exists, and the deformation amount of each deformation region, wherein multiple piezoelectric ceramics are arranged along the circumferential direction of the photomask, and each region on the photomask corresponds to at least one piezoelectric ceramic. Based on the deformation information of the photomask, determine the deformation correction amount corresponding to the deformation information of the photomask; Based on the deformation correction amount, a corresponding control electrical signal is generated. The control electrical signal is used to control the generation of a driving force to adjust the attitude of the photomask, so as to correct the deformation of the photomask. This includes: determining the required driving voltage value for each deformation region based on the deformation correction amount for each deformation region; generating a control electrical signal corresponding to each deformation region based on the required driving voltage value for each deformation region; wherein, the control electrical signal corresponding to a deformation region is used to control the piezoelectric ceramic disposed in the deformation region, so that the piezoelectric ceramic generates a driving force corresponding to the driving voltage value of the deformation region, so as to apply a force to the area of ​​the photomask along its surface direction, so that the photomask moves in the driving direction of the driving force, so as to correct the deformation of the deformation region.

2. The photomask deformation correction method according to claim 1, characterized in that, The step of determining the deformation correction amount corresponding to the deformation information of the photomask based on the deformation information of the photomask includes: Based on the pre-set mapping relationship between deformation and deformation correction, the deformation correction amount mapped to the deformation of each deformation region is determined.

3. The photomask deformation correction method according to claim 2, characterized in that, The deformation correction includes the displacement correction.

4. The photomask deformation correction method according to claim 2 or 3, characterized in that, The acquisition of the deformation information of the photomask includes: The deviation regions with positional deviations among multiple regions of the photomask are identified and designated as the deformation regions; The deformation amount of each deformation region is determined based on the positional deviation of each deformation region.

5. The photomask deformation correction method according to claim 4, characterized in that, Each area of ​​the photomask is marked with a location indicator; The determination of the deviation regions, which are among the multiple regions of the photomask where positional deviations exist, includes: Before or after executing any exposure process, obtain the actual position information of the light source illuminating the wafer through the position markers of each region; Based on the actual position information and the set position information of the light source illuminating the wafer through the position markers of each region, the deviation regions with positional deviations are determined among the multiple regions.

6. The photomask deformation correction method according to claim 2 or 3, characterized in that, The acquisition of the deformation information of the photomask includes: Obtain pre-stored deformation information of the photomask corresponding to each exposure process. The deformation information includes: the deformation region of the photomask corresponding to each exposure process, and the deformation amount of the deformation region.

7. A photomask deformation correction system, characterized in that, include: A deformation information acquisition unit is adapted to acquire the deformation of a photomask, wherein the photomask includes multiple regions, and the deformation information includes: at least one deformed region of the photomask where deformation exists, and the deformation of each deformed region. The deformation correction control unit is adapted to determine the deformation correction amount corresponding to the deformation information of the photomask based on the deformation information of the photomask, and to generate a corresponding control electrical signal based on the deformation correction amount; A deformation correction unit is adapted to generate a driving force for adjusting the orientation of the photomask according to the control electrical signal, so as to correct the deformation of the photomask. The deformation correction unit includes: a plurality of piezoelectric ceramics, the plurality of piezoelectric ceramics being arranged along the circumference of the photomask, and at least one piezoelectric ceramic corresponding to a region on the photomask. The deformation correction control unit includes: The deformation correction calculation module is suitable for determining the deformation correction amount mapped to the deformation amount of each deformation region according to the pre-set mapping relationship between the deformation amount and the deformation correction amount. The deformation correction control module is adapted to determine the required driving voltage value for each deformation region based on the deformation correction amount of each deformation region, and to generate the corresponding control electrical signal for each deformation region based on the required driving voltage value of each deformation region. In this process, a control electrical signal corresponding to a deformation region is used to control the piezoelectric ceramic disposed in the deformation region, so that the piezoelectric ceramic generates a driving force corresponding to the driving voltage value of the deformation region, thereby applying a force to the area of ​​the photomask along its surface direction, so that the photomask moves in the driving direction of the driving force, thereby correcting the deformation of the deformation region.

8. A lithography machine, characterized in that, include: Photomask; The photomask deformation correction system of claim 7 is suitable for correcting the deformation of the photomask.

9. A data processing device, characterized in that, The method includes a memory and a processor, wherein the memory is adapted to store one or more computer instructions, and the processor, when executing the computer instructions, performs the photomask deformation correction method according to any one of claims 1 to 6.

10. A computer-readable storage medium, characterized in that, The device stores computer instructions, which, when executed, perform the photomask deformation correction method according to any one of claims 1 to 6.

11. A computer program product, characterized in that, It includes computer instructions that, when executed by a processor, implement the photomask deformation correction method according to any one of claims 1 to 6.

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