Photomask correction apparatus and method

Abstract

The present application provides a photomask correction method capable of improving the precision of a photomask. The photomask correction method includes: measuring an intensity profile of a laser; obtaining etching amount data corresponding to the measured intensity profile by using a library; determining process parameters of the laser based on the etching amount data; and correcting the photomask by using the laser according to the determined process parameters.

Description

TECHNICAL FIELD

[0001] The present invention relates to a photomask correction apparatus and method BACKGROUND

[0002] In manufacturing a semiconductor device or a display device, various processes such as photolithography, etching, ashing, ion implantation, thin film deposition, cleaning, etc. are performed. Here, the photolithography process includes a coating, an exposure, and a development process. A photosensitive film is formed on a substrate (i.e., the coating process), a circuit pattern is exposed on the substrate on which the photosensitive film is formed (i.e., the exposure process), and a selectively developed on the exposed area on the substrate (i.e., the development process). SUMMARY

[0003] PROBLEMS TO BE SOLVED BY THE INVENTION

[0004] On the other hand, a photomask used in the exposure process needs to satisfy high requirements on transmission uniformity, flatness, pureness, and temperature stability. In addition, the photomask must have high precision, and for this, a correction process is performed on the photomask before using the photomask.

[0005] The present invention relates to a photomask correction apparatus and method

[0006] The present invention relates to a photomask correction apparatus and method

[0007] The present invention relates to a photomask correction apparatus and method

[0008] SOLUTION TO PROBLEM

[0009] To solve the above problem, a photomask correction method according to an aspect of the present invention includes the steps of measuring an intensity profile of a laser, acquiring etching amount data corresponding to the measured intensity profile using a library, determining process parameters of the laser based on the etching amount data, and correcting a photomask with the laser according to the determined process parameters.

[0010] To solve the above technical problem, a photomask correction method according to another aspect of the present application includes the steps of: measuring an intensity profile of laser light supplied from a laser generator using a beam profiler provided inside a main port during a waiting period of the laser generator at the main port; forming a liquid film by supplying a chemical liquid onto a photomask including a first region and a second region; acquiring etching amount data corresponding to the measured intensity profile using a library including a plurality of intensity profiles and a plurality of etching amount data corresponding to the plurality of intensity profiles; determining an irradiation time of the laser light based on the etching amount data; and heating the liquid film of the second region using the laser light for the determined irradiation time, and not heating the liquid film of the first region.

[0011] To solve the above another technical problem, a photomask correction apparatus according to an aspect of the present application includes: a process chamber; a support unit provided inside the process chamber and supporting a photomask; a chemical liquid supply unit provided inside the process chamber and forming a liquid film by supplying a chemical liquid to the photomask; a laser module provided inside the process chamber and including a laser generator for irradiating laser light to the liquid film; a main port at which the laser generator waits, and which is used to measure an intensity profile of the laser light; a storage unit for storing a library including a plurality of intensity profiles and a plurality of etching amount data corresponding to the plurality of intensity profiles; and a controller acquiring etching amount data corresponding to the measured intensity profile using the library, determining a process parameter of the laser light based on the etching amount data, and correcting the photomask using the laser light according to the determined process parameter.

[0012] Particulars of other embodiments are contained in the detailed description and the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 is a schematic view for explaining a photomask correction apparatus according to some embodiments of the present application.

[0014] Figure 2 is a plan view for explaining the photomask correction apparatus of Figure 1 .

[0015] Figure 3 is a graph for explaining an output of a laser generator according to a usage period.

[0016] Figure 4 and Figure 5 are graphs showing a library stored in a storage unit of Figure 2 .

[0017] Figure 6 is a flowchart for explaining a method of creating a library.

[0018] Figure 7 is a plan view of a photomask.

[0019] Figure 8 is a diagram for explaining the operation of the laser module.

[0020] Figure 9 is a diagram for explaining the etching process performed in Figure 7 region A of the semiconductor wafer.

[0021] Figure 10 is a diagram for explaining the etching process performed in Figure 7 region B of the semiconductor wafer.

[0022] Figure 11 is a diagram for explaining the etching process performed in Figure 7 region C of the semiconductor wafer.

[0023] Figures 12 to 16 for explaining the operation of the photomask correction apparatus according to some embodiments of the present application.

[0024] Explanation of reference numerals

[0025] 1: photomask correction apparatus 10: process chamber

[0026] 20: laser module 21: laser generator

[0027] 22: driving section 24: power supply section

[0028] 50: support unit 90: main port

[0029] 99: beam profiler 100: controller

[0030] 110: storage unit DETAILED DESCRIPTION

[0031] Hereinafter, preferred embodiments of the present application will be described in detail with reference to the accompanying drawings. Advantages and features of the present application and methods of achieving the advantages and features will become apparent from embodiments described below in detail in conjunction with the accompanying drawings. However, the present application is not limited to embodiments disclosed hereinafter but can be implemented in various different forms, and the embodiments are provided only to make the disclosure of the present application complete and to completely convey the scope of the present application to those skilled in the art to which the present application pertains, and the present application is defined only by the scope of the claims. Throughout the specification, like reference numerals refer to like constituent elements.

[0032] Spatial relative terms, such as "below," "lower," "bottom," "above," "upper," and the like, can be used herein for ease of description to describe one element or constituent's or element's or constituent's relationship to another element(s) or constituent(s) or spatial orientation and is in no way intended to limit the position that the element, constituent, or element or constituent can be in after being used or manufactured. For example, when an element illustrated in the drawings is turned over, an element described as being "below" or "under" another element can be positioned "above" the other element. As such, exemplary term "below" can include both directions, below and above. An element can also be oriented in another direction, and thus the spatial relative terms can be interpreted based on the orientation.

[0033] Although first, second, etc. are used to describe various elements, constituents, and / or parts, it is apparent that the elements, constituents, and / or parts are not limited by these terms. These terms are used only to distinguish one element, constituent, or part from other elements, constituents, or parts. Thus, within the technical idea of the present application, the first element, first constituent, or first part mentioned below can be apparently a second element, second constituent, or second part.

[0034] Hereinafter, embodiments of the present application will be described in detail with reference to the accompanying drawings, and when described with reference to the drawings, the same or corresponding constituents are given the same reference numerals regardless of the figure number, and repetitive description thereof will be omitted.

[0035] Figure 1 is a schematic view for explaining a photomask correction apparatus according to some embodiments of the present application. Figure 2 is a plan view for explaining the photomask correction apparatus of Figure 1 . Figure 3 is a graph for explaining the output of a laser generator according to the service life.

[0036] First, referring to Figure 1 and Figure 2 , a photomask correction apparatus 1 according to some embodiments of the present application includes a process chamber 10, a support unit 50, a chemical liquid supply unit 30, a laser module 20, a main port 90, a controller 100, and a storage unit 110, etc.

[0037] The process chamber 10 provides a processing space for performing a correction process.

[0038] The support unit 50 supports a photomask PM in the processing space of the process chamber 10. For example, the main body of the support unit 50 has a substantially circular upper surface when viewed from above. The support unit 50 is rotatable by a driving unit 55. In addition, the support unit 50 can also be vertically moved by the driving unit 55.

[0039] The chemical liquid supply unit 30 supplies a chemical liquid to the photomask PM. The chemical liquid supply unit 30 includes a nozzle 31, a nozzle support 35, and a chemical liquid storage (not shown), etc. The nozzle 31 can be located above (i.e., in the Z direction) the support unit 50. The nozzle 31 is provided at one end of the nozzle support 35, and the nozzle support 35 can perform an arcuate motion (see D1 of Figure 2 , but is not limited thereto. According to the movement of the nozzle support 35, the nozzle 31 can wait at a first waiting position, then move to a first supply position, and supply a chemical liquid onto the photomask PM. The chemical liquid used to etch the photomask PM can vary depending on the material of the photomask PM.

[0040] After the chemical liquid supply unit 30 supplies a chemical liquid to the photomask PM, the laser module 20 heats the chemical liquid supplied onto the photomask PM by irradiating laser light. The etching amount of the photomask PM generated by the chemical liquid heated by laser light is greater than the etching amount of the photomask PM generated by the chemical liquid that is not heated. The etching amount of the photomask PM can vary depending on the degree of heating by laser light. This will be described later with reference to Figures 7 to 11 .

[0041] The laser module 20 includes a laser generator 21, a support 25, a driving portion 22, and a power supply portion 24. The laser generator 21 can be located above (i.e., in the Z direction) the support unit 50. The laser generator 21 receives power from the power supply portion 24 and generates laser light. For example, the laser generator 21 can include a laser diode. The laser generator 21 can be provided at one end of the support 25, and the support 25 can perform an arcuate motion (see D2 of Figure 2 , but is not limited thereto. According to the movement of the support 25, the laser generator 21 can wait at a second waiting position, then move to a second supply position, and irradiate laser light.

[0042] In addition, the support unit 50 can be rotated (see reference sign S). Since the support 25 of the laser module 20 performs an arcuate motion, if the support unit 50 does not move, the laser generator 21 cannot irradiate laser light to a partial region of the photomask PM. Therefore, the support unit 50 is rotated about a shaft, thereby enabling the laser generator 21 to irradiate laser light to all regions of the photomask PM. For example, the support unit 50 can be rotated by a first angle and then stopped, the laser generator 21 irradiates laser light to a first target position, then the support unit 50 is rotated by a second angle and then stopped, and the laser generator 21 irradiates laser light to a second target position.

[0043] On the other hand, the second waiting position where the laser module 20 waits can be the main port 90. The main port 90 is shown in the drawing as being arranged at one side (e.g., in the X direction) within the process chamber 10, but is not limited thereto.

[0044] A beam profiler 99 is disposed in the main port 90. The laser module 20 can irradiate laser light to the beam profiler 99, and the intensity profile of the laser light provided from the laser module 20 can be measured by the beam profiler 99.

[0045] The controller 100 controls the support unit 50, the chemical liquid supply unit 30, the laser module 20, the main port 90, and the like.

[0046] In particular, according to the photomask modification apparatus 1 of some embodiments of the present application, the photomask PM is brought into the process chamber 10, the intensity profile of the laser light is measured before performing the modification process on the brought-in photomask PM, and the process parameters of the laser light are determined based on the measurement result.

[0047] Specifically, even if the same power is provided to the laser generator 21 (e.g., a laser diode), the output of the laser generator 21 can be different.

[0048] Here, with reference to Figure 3 , the x-axis indicates the service life, and the y-axis indicates the output. The output (i.e., the intensity profile) of the laser generator 21 (e.g., a laser diode) can be different according to the initial, middle, and final stages. Assuming that the life of the laser generator 21 is 100%, 0% to 20% can correspond to the initial stage, 20% to 80% can correspond to the middle stage, and 80% to 100% can correspond to the final stage. This division is merely an example and is not limited thereto. When the same power (i.e., the same current) is provided to the laser generator 21 at the initial / middle / final stages, the output Tb of the laser generator 21 corresponding to the middle stage reaches the target value T, but the output Ta of the laser generator 21 corresponding to the initial stage is greater than the target value T, and the output Tc of the laser generator 21 corresponding to the final stage is less than the target value T.

[0049] As described above, the etching amount of the photomask PM is different according to the degree of heating of the chemical liquid. However, since the output of the laser generator 21 can vary according to the service life of the laser generator 21, the degree of heating of the chemical liquid can vary according to the service life of the laser generator 21. Thereby, the etching amount of the photomask PM can be changed so that the photomask PM is etched more or less than the target etching amount.

[0050] However, in the photomask modification apparatus according to some embodiments of the present application, before performing the process of modifying the photomask PM, the laser module 20 irradiates laser light to the beam profiler 99 to measure the intensity profile of the laser light. Based on the measurement result, the controller 100 can adjust the etching amount of the photomask PM to the target value by changing the process conditions related to the laser light.

[0051] Here, refer to Figure 4 and Figure 5 This describes the method by which the controller 100 changes the laser-related process conditions. Figure 4 and Figure 5 It is used for explanation Figure 2 A diagram of the libraries stored in the storage unit.

[0052] As described above, the storage unit 110 includes a library containing etch amount data corresponding to the intensity profile of the laser.

[0053] Storage cell 110 may include non-volatile memory (e.g., programmable read-only memory (OTPROM), PROM, EPROM, EEPROM, mask ROM, flash ROM, flash memory, PRAM, RRAM, MRAM, hard disk or solid-state drive (SSD)) and / or volatile memory (e.g., DRAM, SRAM or SDRAM). Storage cell 110 may include internal memory and / or external memory.

[0054] Figure 4 Library 120 shown includes an etching amount corresponding to the intensity profile of the laser. Figure 4 The values ​​shown are merely examples. When the intensity profile measured by beam analyzer 99 is 10, controller 100 can anticipate an etching amount of 200 using library 120. If the target value is 200, the laser-related process parameters are not changed. If the target value is 300, the laser-related process parameters are changed. For example, by increasing the laser irradiation time, the time for heating the chemical solution by the laser is increased. If the target value is 100, the laser irradiation time is decreased, thereby reducing the time for heating the chemical solution by the laser. The amount of process parameters to be changed can be determined based on pre-prepared logic blocks. For example, to increase the etching amount by 10%, the irradiation time can be increased by 10%, but this is not limited to. In addition, other process parameters besides the laser irradiation time may include, for example, the spacing between the laser and the photomask, the chemical solution concentration, etc.

[0055] Figure 5 Library 121 shown includes the intensity profile of the laser, process parameters, and the amount of etching corresponding to the intensity profile of the laser and the process parameters.

[0056] In library 121, process parameters (C11, C12, C21, C22, C31, C32, C91, and C92) corresponding to various cases are provided for each intensity profile, and the corresponding etching amount is recorded for each case. For example, when the intensity profile is 10 and the process parameter is C21 (irradiation time is 10), the etching amount can be 200, and when the process parameter is C22 (irradiation time is 15), the etching amount can be 250.

[0057] When the intensity profile measured by beam analyzer 99 is 10, and the current process parameter is C21 (irradiation time is 10), controller 100 can predict an etching amount of 200 using library 120. If the target value is 200, the laser-related process parameters are not changed. If the target value is 250, the laser-related process parameters are changed. For example, the process parameter is changed to C22 (increasing the irradiation time to 15), thereby increasing the time for heating the chemical solution by the laser. Controller 100 can determine how much to change the process parameters by referring to library 121. If the target etching amount is not found in library 121, the target etching amount can be determined based on pre-prepared logic blocks.

[0058] Here, we will refer to Figure 6 Describe the methods for creating libraries 120 and 121. Figure 6 This is a flowchart illustrating the method for creating a library.

[0059] Reference Figure 6 This paper describes a method for creating a library by testing N lasers. The N lasers can have different intensity profiles or different process parameters (irradiation time, spacing between the laser and the photomask, etc.).

[0060] First, the intensity profile of the i-th laser is obtained (S210). For example, the i-th laser is irradiated onto a beam analyzer, and the intensity profile of the i-th laser is obtained through the beam analyzer. For example, by irradiating the i-th laser onto the beam analyzer, an image of the i-th laser is obtained from the beam analyzer. The obtained image is divided into a plurality of first pixels, and the intensity can be obtained from each of the plurality of first pixels, thereby obtaining an intensity profile in pixels.

[0061] Next, the photomask is modified using the i-th laser (S220). Specifically, a chemical solution is supplied to the photomask to form a liquid film on the photomask, and the target area of ​​the liquid film is heated by irradiating the liquid film with the i-th laser. The photomask is then etched using the heated chemical solution.

[0062] Then, the corrected photomask is analyzed to obtain the amount of etching produced in the photomask (S230). Specifically, an image of the corrected photomask is obtained using an electron microscope. The obtained image can be divided into multiple second pixels, and the amount of etching can be obtained from each of the multiple second pixels, thereby obtaining the amount of etching in pixels. For example, the electron microscope can be a scanning electron microscope (SEM), a transmission electron microscope (TEM), etc.

[0063] Next, the intensity profile and etching amount of the i-th laser are calculated (S240).

[0064] Next, check if i is less than N (S250). If i is less than N, increment i by 1 (S260) and return to operation S210. If i equals N, end the library creation.

[0065] Now refer to Figures 7 to 11 The operation of a photomask correction apparatus according to some embodiments of the present invention is described.

[0066] Figure 7 It is a planar diagram of the photomask. Figure 8 This is a diagram used to illustrate the operation of the laser module. Figure 9 It is used to explain in Figure 7 A diagram showing the etching process that takes place in region A. Figure 10 It is used to explain in Figure 7 A diagram showing the etching process that takes place in region B. Figure 11 It is used to explain in Figure 7 A diagram showing the etching process that takes place in region C.

[0067] Reference Figure 7 and Figure 8 The photomask PM consists of three distinct regions: a first region A, a second region B, and a third region C.

[0068] The upper surface of the photomask PM is coated with chemical liquid 39.

[0069] Region A is the region that does not require laser heating, Region B is the region that requires more etching than Region A, and Region C is the region that requires more etching than Region B.

[0070] like Figure 8 As shown, laser module 20a irradiates the chemical liquid 39 in the second region B with laser light for time t1. Additionally, laser module 20b irradiates the chemical liquid 39 in the third region C with laser light for a time t2 longer than t1. For example, the unit-time output of laser module 20a is the same as that of laser module 20b.

[0071] Here, refer to Figure 9 Before the correction process, the width of the trench formed in the first region A of the photomask PM is W0. After being etched by chemical solution 39 without laser heating, the width of the trench becomes W1.

[0072] Reference Figure 10 During time t1, after etching by chemical solution 39 heated by laser module 20a, the width of the trench becomes W2.

[0073] Reference Figure 11During time t2, which is longer than time t1, after etching by chemical solution 39 heated by laser module 20b, the width of the trench becomes W3, which is greater than W2.

[0074] It can be accessed through a reference storage unit (reference) Figure 1 The library stored in (110) determines t1 and t2 as irradiation times.

[0075] Now refer to Figures 12 to 16 The operation of a photomask correction apparatus according to some embodiments of the present invention is described.

[0076] Reference Figure 12 This is the state where the photomask PM has not entered the process chamber 10. The nozzle 31 of the chemical supply unit 30 waits at the first waiting position P1. The laser generator 21 of the laser module 20 waits at the second waiting position P2. During the waiting period of the laser generator 21, the laser generator 21 supplies laser light to the beam analyzer 99 located in the main port 90. The intensity profile of the laser generator 21 is measured by the beam analyzer 99.

[0077] Reference Figure 13 The photomask PM is introduced into the process chamber 10, so that the photomask PM is placed on the support unit 50.

[0078] Reference Figure 14 The nozzle 31 of the chemical liquid supply unit 30 moves above the photomask PM and supplies chemical liquid to the photomask PM. A liquid film is formed on the photomask PM.

[0079] Reference Figure 15 The nozzle 31 of the chemical liquid supply unit 30 returns to the first waiting position P1. The laser generator 21 of the laser module 20 moves to the third region C of the photomask PM (refer to...). Figure 7 Above. Laser generator 21 irradiates the chemical liquid located in the third region C with laser light for time t2.

[0080] Reference Figure 16 The laser generator 21 of laser module 20 moves to the second region B of photomask PM (refer to...). Figure 7 Above. Laser generator 21 irradiates the chemical liquid located in the second region B with laser light for time t1.

[0081] Controller (reference) Figure 1 100) can be accessed through a reference storage unit ( Figure 1 The library stored in (110) determines t1 and t2 as irradiation times.

[0082] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, those skilled in the art should understand that the present invention can be implemented in other specific forms without changing its technical concept or essential features. Therefore, the above embodiments should be understood as exemplary in all respects, and not restrictive.

Claims

1. A photomask correction method, comprising the following steps: Measure the intensity profile of the laser; Use a library to obtain etching amount data corresponding to the measured intensity profile; Based on the etching amount data, the process parameters of the laser are determined; as well as The photomask is modified using the laser according to the determined process parameters; The step of using the laser to correct the photomask includes: A liquid film formed of a chemical solution is formed on the photomask. The photomask includes a first region and a second region that are different from each other, wherein the liquid film in the first region is heated by the laser for a first irradiation time, and the liquid film in the second region is heated by the laser for a second irradiation time that is longer than the first irradiation time.

2. The photomask correction method according to claim 1, wherein, The steps for measuring the intensity profile of the laser include: The laser beam is directed onto a beam analyzer, and the intensity profile is obtained through the beam analyzer.

3. The photomask correction method according to claim 1, wherein, The photomask further includes a third region, wherein the liquid film in the third region is not heated.

4. The photomask correction method according to claim 1, wherein, The process parameters include at least one of the following: laser irradiation time, chemical solution concentration, and the distance between the laser and the photomask.

5. The photomask correction method according to claim 1, further comprising, before measuring the intensity profile of the laser: The steps to generate the library, The steps for generating the library include: Irradiate a first laser onto a beam analyzer and obtain a first intensity profile of the first laser through the beam analyzer; The photomask is corrected using the first laser; By analyzing the corrected photomask, the first etching amount generated in the photomask is obtained; and Library the first intensity profile and the first etching amount.

6. The photomask correction method according to claim 5, wherein, The step of obtaining the first intensity profile of the first laser using the beam analyzer includes: A first image of the first laser is obtained using the beam analyzer; Divide the first image into a plurality of first pixels; and The first intensity profile, in pixels, is obtained by acquiring the intensity from each of the plurality of first pixels.

7. The photomask correction method according to claim 5, wherein, The steps for analyzing the modified photomask include: A second image of the corrected photomask was obtained using an electron microscope; Divide the second image into a plurality of second pixels; and The first etching amount is obtained in pixels by obtaining the etching amount from each of the plurality of second pixels.

8. The photomask correction method according to claim 1, wherein, While the laser generator used to irradiate the laser is waiting at the main port, the step of measuring the intensity profile of the laser is performed, and While the laser generator is waiting at the main port, the photomask is brought into the process chamber.

9. A photomask correction method, comprising the following steps: While the laser generator is waiting at the main port, the intensity profile of the laser provided from the laser generator is measured using a beam analyzer located inside the main port. A liquid film is formed by supplying a chemical solution to a photomask comprising a first region, a second region, and a third region. Using a library that includes multiple intensity profiles and multiple etching amount data corresponding to the multiple intensity profiles, etching amount data corresponding to the measured intensity profile is obtained; The laser irradiation time is determined based on the etching amount data; as well as The irradiation time is determined by heating the liquid film in the second region using the laser, without heating the liquid film in the first region; The step of determining the laser irradiation time based on the etching amount data includes: The irradiation time of the laser is determined such that the liquid film in the second region is heated for a first irradiation time, and the liquid film in the third region is heated for a second irradiation time that is longer than the first irradiation time.

10. The photomask correction method according to claim 9, wherein, Before measuring the intensity profile of the laser, the photomask correction method further includes the step of generating the library. The steps for generating the library include: The first laser is irradiated onto the beam analyzer, and the first intensity profile of the first laser is obtained through the beam analyzer. The first laser is used to correct the photomask; By analyzing the corrected photomask, the first etching amount generated in the photomask is obtained; and Library the first intensity profile and the first etching amount.

11. The photomask correction method according to claim 10, wherein, The step of obtaining the first intensity profile of the first laser using the beam analyzer includes: A first image of the first laser is obtained using the beam analyzer; Divide the first image into a plurality of first pixels; and The first intensity profile, in pixels, is obtained by acquiring the intensity from each of the plurality of first pixels. The steps for analyzing the modified photomask include: A second image of the corrected photomask was obtained using an electron microscope; Divide the second image into a plurality of second pixels; and The first etching amount is obtained in pixels by obtaining the etching amount from each of the plurality of second pixels.

12. A photomask correction device, comprising: Process chambers; A support unit is disposed within the process chamber and supports the photomask; A chemical solution supply unit is disposed within the process chamber and forms a liquid film by supplying chemical solution to the photomask; A laser module is disposed within the process chamber and includes a laser generator for irradiating the liquid film with laser light; The main port is where the laser generator waits and is used to measure the intensity profile of the laser. A storage unit for a repository, the repository including multiple intensity profiles and multiple etch amount data corresponding to the multiple intensity profiles; as well as The controller uses the library to acquire etching amount data corresponding to the measured intensity profile, determines the laser process parameters based on the etching amount data, and uses the laser to correct the photomask according to the determined process parameters. The photomask includes a first region and a second region that are different from each other. The liquid film in the first region is heated by the laser for a first irradiation time, and the liquid film in the second region is heated by the laser for a second irradiation time that is longer than the first irradiation time.

13. The photomask correction apparatus according to claim 12, wherein, A beam analyzer is installed at the main port, and The laser beam is directed onto the beam analyzer, thereby obtaining the intensity profile of the laser beam through the beam analyzer.

14. The photomask correction apparatus according to claim 12, wherein, The photomask also includes a third region, wherein the liquid film in the third region is not heated by the laser.

15. The photomask correction apparatus according to claim 12, wherein, The process parameters include at least one of the following: laser irradiation time, chemical solution concentration, and the distance between the laser and the photomask.

16. The photomask correction apparatus according to claim 12, wherein, The intensity profile of the laser is measured while the laser generator is waiting at the main port.

17. The photomask correction apparatus according to claim 16, wherein, While the photomask is entering the process chamber, the laser generator waits at the main port.

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