Photomask deformation correction method and system, photoetching machine, equipment, medium and program

Abstract

The embodiment of the invention provides a photomask deformation correction method and system, a photoetching machine, equipment, a medium and a program, and the method comprises the steps: obtaining the deformation information of a photomask; determining a deformation correction amount corresponding to the deformation information of the photomask according to the deformation information of the photomask; according to the deformation correction amount, a corresponding control electric signal is generated, and the control electric signal is used for controlling and generating driving force for adjusting the posture of the photomask so as to correct deformation of the photomask. By adopting the technical scheme, the deformation of the photomask can be corrected, so that the deformation of the photomask is reduced, and the photoetching precision is improved.

Description

Technical Field

[0001] Embodiments of the present invention relate to the field of semiconductor manufacturing technology, and in particular, to a mask deformation correction method, system, lithography machine, equipment, medium and program. Background Art

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

[0003] During the exposure process of the photolithography process, the pattern on the mask will be mapped onto the photoresist, and then through a series of processing, the pattern on the photoresist will be preserved, thereby realizing the pattern transfer from the mask to the wafer.

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

[0005] In this context, how to provide a technical solution to reduce the deformation of the mask has become a technical problem that technical personnel in this field urgently need to solve. Summary of the invention

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

[0007] An embodiment of the present invention provides a mask deformation correction method, comprising:

[0008] Obtaining deformation information of the mask;

[0009] Determining a deformation correction amount corresponding to the deformation information of the photomask according to the deformation information of the photomask;

[0010] A corresponding control electrical signal is generated according to the deformation correction amount, and the control electrical signal is used to control the generation of a driving force for adjusting the posture of the photomask to correct the deformation of the photomask.

[0011] Optionally, the mask includes a plurality of regions, and the deformation information includes: at least one deformation region where the mask is deformed, and the deformation amount of each deformation region;

[0012] The step of determining the deformation correction amount corresponding to the deformation information of the photomask according to the deformation information of the photomask comprises:

[0013] According to the preset mapping relationship between the deformation amount and the deformation correction amount, the deformation correction amount mapped to the deformation amount of each deformation area is determined respectively.

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

[0015] Optionally, generating a corresponding control electrical signal according to the deformation correction amount, wherein the control electrical signal is used to control the generation of a driving force for adjusting the posture of the photomask to correct the deformation of the photomask, includes:

[0016] Determining the driving voltage value required for each deformation area according to the deformation correction amount of each deformation area;

[0017] Generate control electrical signals corresponding to each deformation area according to the driving voltage value required by each deformation area;

[0018] The 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 mask moves in the driving direction of the driving force to correct the deformation amount of the deformation region.

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

[0020] Determine a deviation region having position deviation among the plurality of regions of the mask and use the deviation region as the deformation region;

[0021] The deformation amount of each deformation area is determined according to the position deviation of each deformation area.

[0022] Optionally, each area of ​​the light mask is provided with a position mark;

[0023] The step of determining a deviation region having position deviation among the plurality of regions of the mask comprises:

[0024] Acquire the actual position information of the light source irradiating the wafer through the position marks of each area before or after executing any exposure process;

[0025] According to the actual position information and the set position information of the light source irradiated onto the wafer through the position marks of each area, the deviation area having the position deviation in the multiple areas is determined.

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

[0027] The pre-stored deformation information corresponding to each exposure process of the photomask is obtained, wherein the deformation information includes: a deformation region where the photomask is deformed corresponding to each exposure process, and a deformation amount of the deformation region.

[0028] The embodiment of the present invention further provides a mask deformation correction system, comprising:

[0029] A deformation information acquisition unit, adapted to acquire the deformation amount of the mask;

[0030] A deformation correction control unit, adapted to determine a deformation correction amount corresponding to the deformation information of the mask according to the deformation information of the mask, and to generate a corresponding control electrical signal according to the deformation correction amount;

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

[0032] Optionally, the mask includes a plurality of regions, and the deformation information includes: at least one deformation region where the mask is deformed, and the deformation amount of each deformation region;

[0033] The deformation correction control unit comprises:

[0034] The deformation correction amount calculation module is adapted to determine the deformation correction amount mapped by the deformation amount of each deformation area according to the preset mapping relationship between the deformation amount and the deformation correction amount;

[0035] The deformation correction control module is adapted to determine the driving voltage value required for each deformation area according to the deformation correction amount of each deformation area, and to generate a control electrical signal corresponding to each deformation area according to the driving voltage value required for each deformation area;

[0036] The 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 mask moves in the driving direction of the driving force to correct the deformation amount of the deformation region.

[0037] Optionally, the deformation correction unit includes: a plurality of piezoelectric ceramics, the plurality of piezoelectric ceramics are arranged along the circumference of the mask, and one area on the mask corresponds to at least one piezoelectric ceramic.

[0038] An embodiment of the present invention further provides a photolithography machine, comprising:

[0039] Photomask;

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

[0041] An embodiment of the present invention further provides a data processing device, comprising a memory and a processor, wherein the memory is suitable for storing one or more computer instructions, and when the processor runs the computer instructions, it executes the mask deformation correction method described in any of the above examples.

[0042] An embodiment of the present invention further provides a computer-readable storage medium storing computer instructions, which, when executed, execute the mask deformation correction method described in any of the aforementioned examples.

[0043] An embodiment of the present invention further provides a computer program product, characterized in that it includes computer instructions, and when the computer instructions are executed by a processor, the method for correcting mask deformation described in any of the above examples is implemented.

[0044] By adopting the mask deformation correction method provided by the embodiment of the present invention, the deformation correction amount corresponding to the deformation information of the mask can be determined according to the acquired deformation information of the mask. Since the deformation information can reflect the deformation degree of the mask, a control electric signal for controlling the generation of a driving force for adjusting the posture of the mask can be generated according to the deformation correction amount. The control electric signal is used to control the generation of a driving force for adjusting the posture of the mask to correct the deformation of the mask. That is, under the control of the control electric signal, by applying a driving force to the mask, the posture of the mask can be adjusted to offset or reduce the deformation of the mask, thereby correcting the deformation of the mask and reducing the deformation of the mask, thereby improving the lithography accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0046] Figure 1 is a flow chart of a mask deformation correction method according to an embodiment of the present invention;

[0047] Figure 2 A flowchart of obtaining deformation information of a mask according to an embodiment of the present invention;

[0048] Figure 3 It is a flow chart of a mask deformation correction method in a specific example of an embodiment of the present invention;

[0049] Figure 4 Schematic diagram of the structure of a mask deformation correction system in an embodiment of the present invention;

[0050] Figure 5 It is a structural schematic diagram of a mask deformation correction system in a specific application scenario in an embodiment of the present invention. DETAILED DESCRIPTION

[0051] As described in the background art, during the exposure process of the photolithography process, the mask will be deformed 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] In order to solve the above technical problems, an embodiment of the present invention provides a method for correcting the deformation of a mask. According to the deformation information of the mask obtained, the deformation correction amount corresponding to the deformation information of the mask can be determined. Since the deformation information can reflect the degree of deformation of the mask, a control electrical signal for controlling the generation of a driving force for adjusting the posture of the mask can be generated according to the deformation correction amount. The control electrical signal is used to control the generation of a driving force for adjusting the posture of the mask to correct the deformation of the mask. That is, under the control of the control electrical signal, by applying a driving force to the mask, the posture of the mask can be adjusted to offset or reduce the deformation of the mask, thereby correcting the deformation of the mask and reducing the deformation of the mask, thereby improving the lithography accuracy.

[0053] In order to enable those skilled in the art to have a clearer understanding of the technical concepts, technical principles, advantages, etc. included in the embodiments of the present invention, the following exemplary descriptions are given through specific embodiments and in combination with specific application scenarios, with reference to the accompanying drawings.

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

[0055] S11, obtaining deformation information of the mask.

[0056] Specifically, by acquiring the deformation information of the photomask, the deformation state of the photomask can be confirmed, and then according to the deformation information of the photomask, a corresponding correction plan can be determined.

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

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

[0059] S12, determining a deformation correction amount corresponding to the deformation information of the mask according to the deformation information of the mask.

[0060] Specifically, the deformation information of the mask can reflect the current deformation state of the mask (for example, the existence of a deformed deformation area and the deformation amount of the deformation area). Therefore, based on the deformation information of the mask, the deformation correction amount corresponding to the deformation information of the mask can be obtained, so as to use the deformation correction amount to correct the current deformation of the mask.

[0061] In some embodiments, the deformation amount can reflect the degree of bending of the deformed area when the mask is deformed; the deformation correction amount can reflect the displacement value required to drive the deformed area to move in order to restore the deformed area to its original state, wherein the larger the deformation amount, the greater the degree of bending of the deformed area, and thus the greater the deformation correction amount required to restore the deformed area to its original state.

[0062] S13, generating a corresponding control electrical signal according to the deformation correction amount.

[0063] Specifically, the deformation correction amount is the displacement value required 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 mask.

[0064] In some embodiments, based on the control electrical signal, a driving force for adjusting the posture of the mask can be generated, that is, by applying the driving force to the mask, the posture of the mask can be adjusted to offset or reduce the deformation of the mask, and then correct the deformation of the mask so that the posture of the mask tends to a preset posture (for example, the posture of the mask when it is not deformed).

[0065] In some examples, based on the control electrical signal, the deformation of the mask can be modified in a targeted manner in multiple different regions.

[0066] It can be seen from the above deformation correction process that the deformation information can reflect the deformation degree of the mask, and then according to the deformation correction amount, a control electric signal for controlling the generation of a driving force for adjusting the posture of the mask can be generated, and the control electric signal is used to control the generation of a driving force for adjusting the posture of the mask to correct the deformation of the mask. That is, under the control of the control electric signal, by applying a driving force to the mask, the posture of the mask can be adjusted to offset or reduce the deformation of the mask, and the deformation of the mask can be corrected, thereby reducing the overlay error of the formed pattern and improving the lithography accuracy.

[0067] In order to enable those skilled in the art to better understand and implement the mask deformation correction method in the embodiment of the present invention, the method is described below through specific examples and in combination with the accompanying drawings.

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

[0069] For some examples, see Figure 2 A flowchart of obtaining deformation information of a mask in an embodiment of the present invention is shown in FIG. Figure 2 As shown, the following steps can be performed:

[0070] S21, determining a deviation region having position deviation among the plurality of regions of the mask and using the deviation region as the deformation region.

[0071] Specifically, during the exposure stage of the photolithography process, when the pattern is transferred to the wafer, the light source is irradiated onto the wafer through the mask. According to the principle of photolithography, the position of the light irradiated onto the wafer through the mask should be the same as the set position information, that is, the position of the pattern transferred to the wafer through the mask should be the same as the pre-set 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 irradiated onto the wafer through the mask shifts, the position of the pattern transferred to the wafer will shift. Therefore, by obtaining the position of the light source irradiated onto the wafer through the mask, the deviation area with position deviation in multiple areas on the mask can be determined.

[0073] That is to say, when the position on the wafer where the light source is irradiated through the mask is the same as the set position information, it means that the mask has not been deformed; when the position on the wafer where the light source is irradiated through the mask is different from the set position information, it means that there is at least one deformation area on the mask, so the light source can be irradiated to the offset area on the wafer as the deformation area on the mask.

[0074] S22, determining the deformation amount of each deformation area according to the position deviation of each deformation area.

[0075] Specifically, to determine the deviation area with position deviation, the position deviation of each deformation area can be determined according to the difference between the actual position of the light source irradiated on the wafer and the set position, and then the deformation amount of each deformation area can be determined according to the position deviation of each deformation area.

[0076] By real-time determining the deviation areas with position deviations in multiple areas of the mask and the deformation amounts of each deformation area, the accuracy of the deformation amounts of the deformation areas can be improved, and thus when correcting the deformation areas, the deformation areas can be accurately corrected and the difficulty of correction can be reduced.

[0077] In some embodiments, to facilitate determination of the position on the wafer where the light source irradiates through the mask, position markers are provided on each region of the mask, and the position on the wafer where the light source irradiates through each position marker is determined to determine the deformed region on the mask.

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

[0079] The actual position information of the light source irradiating the wafer through the position marks of each area is obtained before or after executing any exposure process; the deviation area with position deviation among the multiple areas is determined based on the actual position information and set position information of the light source irradiating the wafer through the position marks of each area.

[0080] Specifically, by comparing the actual position information and the set position information of the light source irradiated on the wafer through the position markers of each area, the deviation area where the position deviation exists can be determined, that is, the area where the deformation occurs on the mask can be determined, and then the deformation amount of each deformed area can be determined based on the difference between the actual position information and the set position information of the light source irradiated on the wafer through the position markers of each area.

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

[0082] That is, by determining the deformed area on the mask before or after obtaining and executing any exposure process, the deformed mask can be corrected in time to reduce the impact of the mask on subsequent exposure processes and improve the quality of the graphics formed by the photolithography process.

[0083] In some embodiments, a position sensor may be provided on the wafer support platform to obtain actual position information of the light source irradiating the wafer through the position markers of each area.

[0084] Specifically, the wafer is placed on the wafer carrier, and by measuring the position of the wafer carrier, the actual position information of the light source irradiating the wafer through the position marks of each area can be obtained. In this case, by setting a position sensor on the wafer carrier, the position sensor detects the position of the light source irradiating through the position marks of each area, which is the actual position information of the light source irradiating the wafer.

[0085] In some embodiments, based on the actual position information and set position information of the light source irradiating the wafer through the position markers of each area, the position deviation of the light source irradiating the wafer through the position markers of each area in the current state can be determined, and then based on the position deviation, the morphological change of the position markers of each area on the mask relative to when the mask is not deformed can be determined to obtain the deformation amount of each deformed area.

[0086] In some embodiments, the light source irradiating the wafer through the position markers of each area should be a certain value (the constant value is generally the default setting value). When the mask is deformed, the position markers of each area will be offset relative to the initial position, and the vector corresponding to the offset is the deformation amount of each deformed area.

[0087] In some embodiments, it is usually necessary to use the same photomask multiple times to perform exposure processing on different batches of wafers. For example, a batch generally has 25 wafers, and the 25 wafers of different batches are exposed using the same photomask.

[0088] In the actual exposure process, the inventors found that for the same photomask, when performing the exposure stage of different batches of wafers, 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 of batch 1 and batch 2, after the wafers are exposed for the first time using the same photomask, the deformation area of ​​the photomask in batch 1 and batch 2, and the deformation amount of the deformation area are the same or tend to be the same.

[0089] In some examples, when using a mask to perform a historical exposure process, the deformation information of the mask when exposing different batches of wafers can be stored, and then when the deformation information of the mask needs to be determined, the pre-stored deformation information corresponding to the mask in each exposure process can be obtained.

[0090] For example, the deformed region of the mask corresponding to each exposure process and the deformation amount of the deformed region may be obtained.

[0091] By directly acquiring the pre-stored deformation information corresponding to each exposure process of the mask, the time required for mask deformation correction can be reduced and the photolithography efficiency can be improved.

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

[0093] In some examples, the deformation correction amount mapped to the deformation amount of each deformation area may be determined according to a preset mapping relationship between the deformation amount and the deformation correction amount.

[0094] As mentioned above, the deformation amount can reflect the degree of bending of the deformed area when the mask is deformed, and the deformation correction amount can reflect the displacement value required to drive the deformed area to move in order to restore the deformed area to its original state. By changing the deformation correction amount applied to the mask, the displacement value of the movement of different areas on the mask can be changed, and then the posture of the mask under different deformation correction amounts (i.e., the deformation amount) can be obtained, thereby determining the mapping relationship between the deformation amount and the deformation correction amount based on multiple corresponding deformation correction amounts and the posture of the mask.

[0095] In some examples, when the deformation area on the mask and the deformation amount of the deformation area are determined by the method in the above examples, the deformation correction amount required for the deformation area can be determined based on the deformation amount. That is, the deformation correction amount required for the deformation area can be automatically obtained based on 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.

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

[0097]

[0098] Among them, ΔY n represents the deformation amount of the mask, a represents the constant term, n represents the position of the deformation correction unit on the mask deformation area, ΔX n represents the control electrical signal output to the deformation correction unit on the mask deformation area, and R represents the remainder.

[0099] It should be noted that a and R are parameters set for correcting the deformation amount. In a specific implementation, the values ​​of a and R can be adjusted according to the fitting process.

[0100] In some embodiments, there is a deformed area on the mask, indicating that the overall flatness of the mask surface has changed, and the morphology of at least one area on the mask has changed relative to other areas on the mask (for example, a certain area has bent). Therefore, by restoring the deformed area to its original state, the deformation of the mask can be corrected to improve the lithography accuracy.

[0101] In some examples, the deformation correction amount includes a displacement correction amount. For any deformation area, the displacement correction amount of the deformation area can be used to express: the displacement value that the deformation area needs to move to offset the deformation amount of the deformation area. Therefore, based on the displacement correction amount of the deformation area of ​​the mask, the deformation area on the mask can be moved according to the displacement value corresponding to the displacement correction amount to perform local precise correction, thereby achieving the corresponding correction effect.

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

[0103] For some examples, see Figure 3 The flowchart of the mask deformation correction method in a specific example of the embodiment of the present invention shown in FIG. 1 can specifically be performed in the following steps:

[0104] S31, determining the driving voltage value required for each deformation area according to the deformation correction amount of each deformation area.

[0105] Specifically, the deformation degrees of different deformation areas on the mask are different, and their corresponding deformation correction amounts are also different. When correcting the deformation of the deformation area, the required driving voltage value is also different. Then, the driving voltage value required for each deformation area can be determined according to the deformation correction amount of each deformation area.

[0106] In some embodiments, the deformation correction amount may include a displacement correction amount, that is, the displacement value that the deformed area needs to move. The displacement value that the deformed area needs to move can be converted into a voltage value. By applying a voltage value to a device or equipment used to drive the deformed area on the mask to move, the device or equipment can be expanded or contracted, thereby realizing the movement of the deformed area. Among them, the "device or equipment" mentioned in the embodiments of the present invention refers to an element that has the function of converting a voltage value into a displacement value (that is, a piezoelectric effect)."

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

[0108] S32, generating control electrical signals corresponding to the respective deformation regions according to the driving voltage values ​​required by the respective deformation regions.

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

[0110] Specifically, the driving voltage value is determined by the deformation correction amount, and the deformation correction amount may include a displacement correction amount that characterizes 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 mask to move in the direction of the driving force (for example, drive the deformed area of ​​the mask to move the corresponding displacement value in the direction of the driving force), thereby correcting the deformation amount of the deformed area.

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

[0112] In some examples, the deformation amount of the deformed area can be corrected by applying force to the area along the surface direction of the mask. That is, after determining the deformed area on the mask, the deformation amount of the deformed area can be corrected by applying force along the surface direction of the mask.

[0113] The embodiment of the present invention further provides a mask deformation correction system corresponding to the above-mentioned mask deformation correction method, which is exemplarily described below with reference to the accompanying drawings through specific examples.

[0114] Reference Figure 4 The structural diagram of a mask deformation correction system in an embodiment of the present invention is shown in FIG. Figure 4 As shown, in some embodiments, the mask 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] A deformation information acquisition unit 110, adapted to acquire a deformation amount of the mask;

[0116] The deformation correction control unit 120 is adapted to determine a deformation correction amount corresponding to the deformation information of the mask according to the deformation information of the mask, and to generate a corresponding control electrical signal according to the deformation correction amount;

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

[0118] The following combination Figure 4 , briefly introduce the working principle of the mask deformation correction system 100:

[0119] The deformation information acquisition unit 110 can obtain the deformation amount of the photomask, and 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 based on the deformation information of the photomask, 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 deformation degree of the photomask, the deformation correction unit 130 can generate a driving force for adjusting the posture of the photomask to correct the deformation of the photomask.

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

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

[0122] In some examples, the deformation information acquisition unit may determine a deviation region with position deviation among multiple regions of the mask as a deformation region, and then determine the deformation amount of each deformation region according to the position deviation of each deformation region.

[0123] The process of the deformation information acquisition unit determining the deformation area and the deformation amount of each deformation area can refer to the above example.

[0124] In some embodiments, when it is determined that a deformed area exists on the mask and the deformation amount of the deformed area, a deformation correction amount corresponding to the deformation amount of the deformed area may be determined to correct the deformation amount of the deformed area.

[0125] In some examples, see 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 amount calculation module 121 is adapted to determine the deformation correction amount mapped to the deformation amount of each deformation area according to the preset mapping relationship between the deformation amount and the deformation correction amount;

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

[0128] Specifically, when the deformation area on the mask and the deformation amount of the deformation area are determined, the deformation correction amount calculation module 121 can determine the deformation correction amount required for the deformation area based on the deformation amount. That is, the deformation correction amount required for the deformation area 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; and then the deformation correction control module 122 can determine the driving voltage value required for each deformation area according to the deformation correction amount of each deformation area.

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

[0130] Specifically, the driving voltage value determined by the deformation correction control module 122 is determined by the deformation correction amount, and the deformation correction amount may include a displacement correction amount that characterizes the displacement value that the deformation area needs to move, and then the deformation correction control module 122 generates a control electrical signal for controlling the provision of the required driving force for each deformation area to correct the deformation amount of the deformation area.

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

[0132] In some embodiments, 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, that is, the control electrical signal is determined according to the deformation amount of the deformation region on the mask, so the deformation region can be corrected.

[0133] In some examples, the deformation correction unit may include a plurality of piezoelectric ceramics, and the plurality of piezoelectric ceramics are arranged along a circumference of the photomask.

[0134] In some examples, one area on the photomask corresponds to at least one piezoelectric ceramic. That is, when it is determined that there is a deformed area on the photomask, a control electrical signal can be applied to the piezoelectric ceramic disposed in the deformed area to drive the deformed area to move through the piezoelectric ceramic to change the deformation state of the deformed area. In some examples, the piezoelectric ceramic can correct the deformation amount of the deformed area by applying force to the area of ​​the photomask along its surface direction.

[0135] In order to enable those skilled in the art to better understand and implement the mask deformation correction solution in the embodiment of the present invention, a specific application scenario is taken as an example for description below.

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

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

[0138] As a specific example, see Figure 5 One of the piezoelectric ceramics P is shown, 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 area on the mask 10A and the deformation amount of each deformation area, the deformation correction control unit 120 can generate a control electrical signal for controlling the movement of the deformation area, and output the control electrical signal to the piezoelectric ceramic P arranged in the deformation area, and then based on the control electrical signal, the piezoelectric ceramic P corresponding to the deformation area can be driven to expand or compress, wherein, 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., stretch) so that the deformation area moves toward the center area of ​​the mask; when the driving voltage value of the control electrical signal changes in a negative direction (from large to small), the piezoelectric ceramic P can be compressed so that the deformation area moves to the side away from the center area of ​​the mask, so as to change the posture of the mask corresponding to the deformation area, and then the deformation of the mask can be corrected.

[0140] It should be noted that, first, the distribution of the piezoelectric ceramics P on the mask 10A is only an example to illustrate that the piezoelectric ceramics P can be arranged in the circumferential direction of the mask 10A to change the posture of the mask 10A, and cannot be understood as a limitation of the present invention; second, Figure 5 Only the electrical connection relationship between one piezoelectric ceramic P and the deformation correction control unit 120 is illustrated. In practical applications, the deformation correction control unit 120 may be electrically connected to all the piezoelectric ceramics P.

[0141] An embodiment of the present invention further provides a lithography machine. In some embodiments, the lithography machine may include a mask and a mask deformation correction system as described in any of the above embodiments. The mask deformation correction system is suitable for correcting the deformation amount of the mask.

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

[0143] In some examples, see Figure 5 The lithography machine may further include a mask stage ZT, and the mask stage ZT is used to carry the mask 10A.

[0144] In some implementations, a vacuum suction cup is further provided between the mask 10A and the mask carrier ZT. Through the vacuum suction cup, a vacuum environment can be generated between the mask 10A and the mask carrier ZT, so that the mask 10A is tightly adsorbed on the mask carrier ZT, preventing the mask 10A from falling off the mask carrier ZT, thereby improving stability during exposure.

[0145] In some embodiments, an embodiment of the present invention provides a data processing device, which may include a memory and a processor. The memory and the processor may communicate with each other through a communication bus; the memory stores one or more computer instructions that can be run on the processor, and when the processor runs the computer instructions, it may execute the mask deformation correction method described in any of the above embodiments. For details, please refer to the above-mentioned related content and will not be repeated here.

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

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

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

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

[0150] The present invention also provides a computer-readable storage medium on which computer instructions are stored. When the computer instructions are run, the mask deformation correction method described in any of the above embodiments of the present invention can be executed. For details, please refer to the above related content and will not be repeated here.

[0151] Among them, the computer-readable storage medium may include any suitable type of memory unit, memory device, memory article, memory medium, storage device, storage article, storage medium and / or storage unit. For example, memory, removable or non-removable medium, erasable or non-erasable medium, writable or rewritable medium, digital or analog medium, hard disk, floppy disk, compact disk read-only memory (CDROM), compact disk recordable (CD-R), compact disk rewritable (CD-RW), optical disk, magnetic medium, magneto-optical medium, removable memory card or disk, various types of digital versatile disks (DVD), magnetic tape, cassette tape, etc. Moreover, the computer instructions may include any suitable type of code implemented by 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, the method for correcting mask deformation described in any of the above embodiments of the present invention is implemented. For details, please refer to the above-mentioned related content and will not be repeated here.

[0153] Although the present specification discloses the above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined by the claims.

Claims

1. A method for correcting mask deformation, characterized in that: include: Obtaining deformation information of the mask; Determining a deformation correction amount corresponding to the deformation information of the photomask according to the deformation information of the photomask; A corresponding control electrical signal is generated according to the deformation correction amount, and the control electrical signal is used to control the generation of a driving force for adjusting the posture of the photomask to correct the deformation of the photomask.

2. The mask deformation correction method according to claim 1, characterized in that: The mask includes a plurality of regions, and the deformation information includes: at least one deformation region where the mask is deformed, and the deformation amount of each deformation region; The step of determining the deformation correction amount corresponding to the deformation information of the photomask according to the deformation information of the photomask comprises: According to the preset mapping relationship between the deformation amount and the deformation correction amount, the deformation correction amount mapped to the deformation amount of each deformation area is determined respectively.

3. The mask deformation correction method according to claim 2, characterized in that: The deformation correction amount includes a displacement correction amount.

4. The mask deformation correction method according to claim 2, characterized in that: The step of generating a corresponding control electrical signal according to the deformation correction amount, wherein the control electrical signal is used to control the generation of a driving force for adjusting the posture of the photomask so as to correct the deformation of the photomask, comprises: Determining the driving voltage value required for each deformation area according to the deformation correction amount of each deformation area; Generate control electrical signals corresponding to each deformation area according to the driving voltage value required by each deformation area; The 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 mask moves in the driving direction of the driving force to correct the deformation amount of the deformation region.

5. The mask deformation correction method according to claim 2 or 3, characterized in that: The step of obtaining the deformation information of the mask comprises: Determine a deviation region having position deviation among the plurality of regions of the mask and use the deviation region as the deformation region; The deformation amount of each deformation area is determined according to the position deviation of each deformation area.

6. The mask deformation correction method according to claim 5, characterized in that: Each area of ​​the light mask is respectively provided with a position mark; The step of determining a deviation region having position deviation among the plurality of regions of the mask comprises: Acquire the actual position information of the light source irradiating the wafer through the position marks of each area before or after executing any exposure process; According to the actual position information and the set position information of the light source irradiated onto the wafer through the position marks of each area, the deviation area having the position deviation in the multiple areas is determined.

7. The mask deformation correction method according to claim 2 or 3, characterized in that: The step of obtaining the deformation information of the mask includes: The pre-stored deformation information corresponding to each exposure process of the photomask is obtained, wherein the deformation information includes: a deformation region where the photomask is deformed corresponding to each exposure process, and a deformation amount of the deformation region.

8. A mask deformation correction system, characterized in that: include: A deformation information acquisition unit, adapted to acquire the deformation amount of the mask; A deformation correction control unit, adapted to determine a deformation correction amount corresponding to the deformation information of the mask according to the deformation information of the mask, and to generate a corresponding control electrical signal according to the deformation correction amount; The deformation correction unit is adapted to generate a driving force for adjusting the posture of the photomask according to the control electrical signal, so as to correct the deformation of the photomask.

9. The mask deformation correction system according to claim 8, characterized in that: The mask includes a plurality of regions, and the deformation information includes: at least one deformation region where the mask is deformed, and the deformation amount of each deformation region; The deformation correction control unit comprises: The deformation correction amount calculation module is adapted to determine the deformation correction amount mapped by the deformation amount of each deformation area according to the preset mapping relationship between the deformation amount and the deformation correction amount; The deformation correction control module is adapted to determine the driving voltage value required for each deformation area according to the deformation correction amount of each deformation area, and to generate a control electrical signal corresponding to each deformation area according to the driving voltage value required for each deformation area; The 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 mask moves in the driving direction of the driving force to correct the deformation amount of the deformation region.

10. The mask deformation correction system according to claim 8, characterized in that: The deformation correction unit includes: a plurality of piezoelectric ceramics, the plurality of piezoelectric ceramics are arranged along the circumference of the photomask, and one area on the photomask corresponds to at least one piezoelectric ceramic.

11. A photolithography machine, characterized in that: include: Photomask; The photomask deformation correction system described in any one of claims 8 to 10 is suitable for correcting the deformation amount of the photomask.

12. A data processing device, characterized in that: It comprises a memory and a processor, wherein the memory is suitable for storing one or more computer instructions, and when the processor runs the computer instructions, it executes the mask deformation correction method according to any one of claims 1 to 7.

13. A computer-readable storage medium, characterized in that: Computer instructions are stored, and when the computer instructions are executed, the mask deformation correction method according to any one of claims 1 to 7 is executed.

14. A computer program product, characterized in that The method comprises computer instructions, which, when executed by a processor, implement the mask deformation correction method according to any one of claims 1 to 7.

Images