JP2004077840A - Mask and mask defect modifying method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an eaves type Levenson phase shift mask for transferring a fine pattern in which fragments of eaves are restored with high accuracy, and to provide a mask defect modifying method for restoring broken parts of the eaves of the eaves type phase shift mask. <P>SOLUTION: The mask defect modifying method has a process for detecting a defection place part where eaves are broken, a process for performing the simulation of the distribution of the intensity of transmitted light and of a pattern to be imprinted, a process for deciding the width of a light shielding material to be formed at the caves broken part and a process for forming the light shielding part with the width and a mask is obtained by this method. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a mask used in a lithography process for manufacturing a semiconductor device and a method for repairing a mask defect, and more particularly to a Levenson-type phase shift mask and a method for repairing the defect.
[0002]
[Prior art]
2. Description of the Related Art Semiconductor integrated circuits continue to be highly integrated and miniaturized. In manufacturing the semiconductor integrated circuit, the lithography technique is particularly important as a key to processing. Regarding the mask manufacturing technology used in such a lithography technology, a phase shift mask method was proposed in 1982 by Levenson et al. Of IBM in addition to a normal binary mask in which a light-shielding film was partially formed. ing. Since then, companies have proposed various phase shift methods.
[0003]
The phase shift mask includes a halftone type phase shift mask, a Levenson type phase shift mask, and the like. The halftone phase shift mask uses a material that transmits light slightly as a light shielding film. Levenson phase shift masks include a shifter-mounted type and a quartz (Qz) engraved type.
[0004]
In the shifter mounting type, a transparent thin film is provided on a mask to provide a phase difference. In the Qz excavation type, a Qz substrate is dug and thinned to provide a phase difference. Since the shifter mounting type is manufactured by a complicated process using, for example, SOG (spin on glass), a Qz digging type Levenson phase shift mask is generalized.
FIG. 12A is a sectional view of a Qz digging type Levenson phase shift mask. As shown in FIG. 12A, a light-shielding film 22 is formed on a Qz substrate 21, and a part of the light transmitting portion 23 where the light-shielding film 22 is not formed is dug (shifter portion 24).
[0005]
FIG. 12B shows the result of performing an electromagnetic field simulation based on the cross-sectional view of FIG. In the Qz digging type Levenson phase shift mask shown in FIG. (See FIG. 12B) deteriorates due to the effect of the waveguide effect and the like.
[0006]
In order to solve this, various methods such as a dual trench type, a shifter width bias type, and an eaves type have been studied. FIG. 13A is a cross-sectional view of a dual trench type phase shift mask, and FIG. 13B shows the balance of transmitted light intensity. In the dual trench type, the first shifter portion 25 and the second shifter portion 26 are formed by digging the Qz substrate 21 at different depths, and a phase difference is given to transmitted light while adjusting the balance of light intensity.
[0007]
FIG. 14A is a sectional view of a shifter width bias type phase shift mask, and FIG. 14B shows the balance of the transmitted light intensity. In the shifter width bias type, the balance of the light intensity is adjusted by changing the widths W ₂₄ and W ₂₃ of the shifter portion 24 and the light-transmitting portion 23 that is not dug, so that the transmitted light has a phase difference.
[0008]
FIG. 15A is a cross-sectional view of the eaves-type phase shift mask, and FIG. 15B shows the balance of the transmitted light intensity. In the eaves type, a part of the Qz substrate 21 below the light-shielding film 22 is removed at the boundary between the shifter 24 and the light-shielding film 22 to form an eaves portion 27. Thereby, a phase difference is given to the transmitted light while adjusting the balance of the light intensity. Of the above-mentioned phase shift masks, the eaves type Levenson phase shift mask is relatively easy to process and can obtain a desired light intensity.
[0009]
[Problems to be solved by the invention]
However, the eaves-type Levenson phase shift mask has a problem that the eaves portion of the light-shielding film is easily broken by a process such as cleaning in manufacturing the mask. At present, there is no correction method when the eaves are broken, so it was necessary to re-create the mask from the beginning.
[0010]
The phase shift mask has a larger number of process steps than a normal binary mask, and a complicated process of excavating Qz is applied. Become.
[0011]
The present invention has been made in view of the above-described problems, and accordingly, the present invention can provide a proper balance of transmitted light intensity even when the eaves are broken, and can be used for transferring a fine pattern. It is an object to provide a shift mask.
Another object of the present invention is to provide a mask defect repair method that can repair a mask so that the mask can be used when the canopy is broken by an eaves type Levenson phase shift mask.
[0012]
[Means for Solving the Problems]
In order to achieve the above object, the mask of the present invention includes at least one first light transmitting region that is a part of the light transmitting substrate and at least one first light transmitting region that is another part of the light transmitting substrate. The second light transmitting region, wherein the second light transmitting region is formed to be thinner than the first light transmitting region so that the phase of the transmitted light of a predetermined wavelength is inverted from the phase of the transmitted light of the first light transmitting region. 2 light transmitting regions, a light shielding film formed on the light transmitting substrate other than the first and second light transmitting regions, and an edge of the light shielding film around the second light transmitting region. An extension portion extending on the second light transmission region, and the first light transmission region formed in a part of the second light transmission region continuously with the edge or the extension portion; A light-shielding material layer having a predetermined width for adjusting the distribution of transmitted light intensity in the second light-transmitting region; And it features.
[0013]
This makes it possible to repair and use the eaves-type Levenson phase shift mask when the eaves is damaged. According to the mask of the present invention, when the eaves-type Levenson phase shift mask is damaged, the necessity of re-creating the mask is reduced, and the throughput of mask production is improved. Further, the cost of manufacturing a mask can be reduced.
[0014]
In order to achieve the above object, the mask defect repairing method of the present invention includes at least one first light transmitting region that is a part of a light transmitting substrate, and at least one other light transmitting region that is another part of the light transmitting substrate. One second light transmitting region, which is formed thinner than the first light transmitting region so that the phase of the transmitted light of a predetermined wavelength is inverted with respect to the phase of the transmitted light of the first light transmitting region. The second light transmitting region, a light shielding film formed on the light transmitting substrate other than the first and second light transmitting regions, and an edge of the light shielding film around the second light transmitting region. A step of detecting a defective portion in which the extended portion is missing, and analyzing the shape and size of the defective portion in the mask having an extended portion extending on the second light transmitting region; Part or in the second light transmitting region continuously with the extension part. A predetermined width for forming a light-shielding material layer in a portion, wherein the predetermined width for reducing the difference in transmitted light intensity between the first light transmitting region and the second light transmitting region is determined by the shape and size of the defective portion. And a step of forming the light shielding material layer with the predetermined width.
[0015]
The step of determining the predetermined width is a step of performing a first simulation of calculating a distribution of transmitted light intensity and a pattern to be transferred under a plurality of conditions in which the shape and size of a defective portion and the width of the light shielding material layer are different in advance. Creating a database from the results of the first simulation; and comparing the shape and size of the defect spot detected by the mask with the database and selecting the predetermined width from the database. including.
[0016]
Alternatively, without creating a database, using the shape and size of the defective portion detected by the mask, the pattern of the transmitted light intensity distribution and the pattern to be transferred under a plurality of conditions where the width of the light shielding material layer is different. May be performed, and the predetermined width may be determined from the result of the second simulation.
The light shielding material layer can be formed, for example, by using a focused ion beam or by sputtering.
[0017]
As a result, in the eaves-type Levenson phase shift mask, the eaves can be repaired without breaking the balance of the transmitted light intensity distribution. Therefore, according to the mask of the present invention, when the eaves-type Levenson phase shift mask is damaged, the necessity of recreating the mask is reduced, and the throughput of mask production is improved. Further, the cost of manufacturing a mask can be reduced.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of a mask and a mask defect correcting method according to the present invention will be described with reference to the drawings.
(Embodiment 1)
FIGS. 1 and 2 show a manufacturing process of the eaves type Levenson phase shift mask. First, as shown in FIG. 1A, a light-shielding film 2 on a quartz (Qz) substrate 1 is etched to form a light transmitting portion 3. As the light shielding film 2, for example, a chromium film is used. FIG. 1A shows a state of a normal binary mask.
[0019]
Next, as shown in FIG. 1B, a resist 4 is applied on the mask, and then superposition drawing is performed by the electron beam EB. Due to the development of the resist 4, only the portion of the resist 4 dug into the Qz substrate 1 is selectively removed. The resist 4 remains on the light transmitting portion where the Qz substrate 1 is not dug.
[0020]
Next, as shown in FIG. 2C, dry etching using the light-shielding film 2 as a mask is performed on the Qz substrate 1 where the resist 4 has been removed. Subsequently, as shown in FIG. 2D, wet etching of the Qz substrate 1 with hydrofluoric acid is performed. Thereby, the dug portion of the Qz substrate 1 extends to the lower part of the light shielding film 2.
[0021]
Thereafter, as shown in FIG. 2E, the resist 4 is peeled off, and the process proceeds to cleaning and inspection steps. The portion where the Qz substrate 1 is dug, that is, the portion that shifts the phase is referred to as a shifter portion 5. In addition, a light transmitting portion in which the Qz substrate 1 is not dug is referred to as a non-shifter portion 6. An eaves portion 7 of the light shielding film 2 extends on the shifter portion 5.
[0022]
Hereinafter, a method of correcting a case where a broken eaves is detected in the inspection process of the manufactured mask will be described. In the inspection process, when a defective portion where the eaves are broken is detected, the shape and the line width of the defective portion are confirmed from above by using a scanning electron microscope (SEM). The SEM measurement result is compared with a simulation result (the result of the first simulation) prepared in advance to correct a defective portion.
[0023]
The simulation will be described with reference to FIGS. FIG. 3A is a cross-sectional view of the eaves-type Levenson phase shift mask in a normal state, that is, without a defect such as eaves breaking. FIG. 3B shows the result of performing an electromagnetic field simulation based on the cross-sectional view of FIG.
[0024]
On the other hand, FIG. 4A is a cross-sectional view of the eaves-type Levenson phase shift mask in a state where a part of the eaves portion 7 is broken (a state in which the eaves broken portion 8 is generated). FIG. 4B shows a result of performing an electromagnetic field simulation based on the cross-sectional view of FIG. Compared with the light intensity of a normal eaves-type Levenson phase shift mask (see FIG. 3B), the simulation results in the state where the eaves are broken (see FIG. 4B) show the shifter portion 5 and the non-shifter portion 6. And the light intensity difference D occurs.
[0025]
From this result, it can be seen that when the eaves are broken, a critical dimension (CD) error increases, and a pattern transfer position shift occurs due to imbalance in light intensity. The above simulation was performed under the conditions of an ArF wavelength (193 nm), a numerical aperture NA = 0.68, a coherence factor σ = 0.34, and a target line width of 70 nm.
[0026]
Next, from the simulation result, a correction condition for minimizing the CD error from the state where the eaves are broken is obtained. FIG. 5A is a cross-sectional view in a state where the eaves are broken. As shown in FIG. 5A, a light-shielding material layer 9 is deposited with a predetermined width on the bent portion of the eaves and on the inner wall of the shifter portion 5 in the vicinity thereof. As the light shielding material layer 9, for example, a carbon film is used. FIG. 5B shows a result of performing an electromagnetic field simulation based on the cross-sectional view of FIG.
[0027]
The width of the light shielding material layer 9 at which the CD error was minimized was determined. FIG. 6 collectively shows simulation results under three conditions with different eaves states. a is a normal state with no eaves breaking (FIG. 3B), b is a state with eaves breaking (FIG. 4B), and c is a state in which a light shielding material layer is formed to correct the eaves bending (FIG. 5 (b)).
[0028]
As described above, the first simulation is performed on the distribution of transmitted light intensity and the pattern to be transferred under a plurality of conditions in which the shape and size of the defective portion are different in advance, and the simulation results are stored in a database. The optimum correction amount can be calculated according to the state of the broken part. The defect is corrected with the optimum correction amount selected from the database.
[0029]
The database used for the defect correction according to the present embodiment includes, specifically, an eave amount (length of an eave portion), a broken position of the eave, a line width of a shifter portion and a non-shifter portion, and a line of a light shielding film 2 (chrome). A simulation (first simulation) is performed using parameters such as the width, the eaves correction amount, and the optical conditions as parameters, and the optimum values of the eaves correction amount capable of controlling the light intensity balance and minimizing the CD error under each condition are collected. is there.
[0030]
With a FIB correcting apparatus as shown in FIG. 7, a carbon film is deposited by a focused ion beam (FIB) with an optimum width obtained based on the above database. In the apparatus shown in FIG. 7, a defect portion is irradiated with a Ga ion beam 13 while blowing an organic gas 12 from a nozzle 11 onto the mask surface.
[0031]
FIG. 7 schematically shows the gas molecules 12. The gas 12 is decomposed by the energy of the ion beam 13 and a carbon film 14 as a light shielding material layer is deposited. This carbon film 14 not only has a sufficient optical density as a light-shielding film, but also has sufficient durability against general mask cleaning.
[0032]
The defect correction is completed by depositing the carbon film by the above method. In the present embodiment, the optimal eaves correction amount is made into a database, and the correction is performed based on the database, but it is possible to detect a defect or the like that does not meet the registered conditions by collating with the database in the inspection process. There is also.
[0033]
In such a case, a new simulation is performed based on the shape and line width data of the defective portion acquired by the SEM after the defect detection (second simulation step). Through this simulation, the optimum value of the eaves correction amount is obtained, and the defect is corrected by the same method as in FIG.
[0034]
FIG. 8 summarizes the correction flow of the present embodiment. In step 1 (ST1), a defect is detected, and the shape and size of the defect are analyzed. In step 2 (ST2), database collation is performed, and in step 3 (ST3), a CD error and light intensity balance are confirmed. If the defect fits the database, the defect is corrected based on the database in step 4 (ST4) and shipped in step 5 (ST5).
[0035]
If the defect does not fit in the database and the optimal correction amount cannot be obtained from the database, a simulation (second simulation) is performed in step 6 (ST6) to calculate the optimal correction amount. Thereafter, the defect is corrected in step 7 (ST7) and the product is shipped (ST5).
[0036]
Alternatively, the optimal correction amount may be calculated by performing a simulation for each defect detection without forming the optimum correction amount in a database. FIG. 9 shows a correction flow in this case. The calculation of the optimum correction amount by simulation may be performed in the same manner as that performed for a defect that does not apply to the database (ST6) in the flow shown in FIG.
[0037]
In the flow of FIG. 9, a defect is detected in step 1 (ST1), and the shape and size of the defect are analyzed. Simulation is performed in step 2 (ST2), and CD error and light intensity balance are confirmed in step 3 (ST3). If the CD error and the light intensity balance are good, the product is shipped in step 4 (ST4).
[0038]
If there is a problem with the CD error and the light intensity balance, a simulation (second simulation) is performed in step 5 (ST5) to calculate an optimal correction amount. Thereafter, the defect is corrected in step 6 (ST6) and the product is shipped (ST4).
According to the mask defect repair method of the present embodiment, even when the eaves is broken by the eaves-type Levenson phase shift mask, it is possible to repair the mask without breaking the light intensity balance.
[0039]
Accordingly, it is not necessary to re-create a phase shift mask having a larger number of process steps than a binary mask. Therefore, it is possible to improve the throughput of the production of a mask and the lithography process using the mask.
Further, according to the mask defect repairing method of the present embodiment, the mask can be repaired not only when the eaves are broken in the manufacturing process of the mask, but also when the eaves are broken by cleaning the used mask. It is possible to extend the life of the mask.
[0040]
(Embodiment 2)
In the present embodiment, defect correction is performed using sputtering. The process flow of the eaves-type Levenson phase shift mask is the same as that of the first embodiment (see FIGS. 1 and 2), and a description thereof will be omitted.
[0041]
In the mask inspection process, as shown in FIG. 10A, when the eaves bent portion 8 is detected, the coordinates of the defective portion 16 are obtained. FIG. 10A shows a resist pattern (top view) 17 formed for correcting a sputter. Electron beam drawing data (EB data) is prepared based on the coordinates of the defect location 16 so that only the resist at the defect location 16 is opened.
[0042]
Next, as shown in FIG. 10B, a resist 18 is applied, and the electron beam EB is exposed only to the defective portion 16 where the eaves are broken. Thereafter, when the resist 18 is developed, only the resist 18 on the defective portion 16 is removed.
Next, as shown in FIG. 11C, chromium 19 is deposited by sputtering. Thereby, the defective portion 16 (see FIG. 10A) is corrected. Thereafter, as shown in FIG. 11D, when the resist 18 is removed, the correction of the defect is completed.
[0043]
Unlike the first embodiment in which the defect is corrected by irradiating the FIB, in the second embodiment, when performing the electron beam exposure on the resist 18, it is necessary to consider the overlay accuracy with the defective portion 16. An overlay margin is determined in advance from overlay accuracy, and EB data is prepared to allow misalignment.
[0044]
When there are a plurality of overhang portions, a drawing area for the number of defects is set in the step of creating EB data. If the resist on each defective portion is removed by electron beam exposure and development, a plurality of defective portions can be corrected by one sputtering.
The repair flow of the present embodiment is the same as that of the first embodiment, except that the defect is repaired by sputtering.
[0045]
That is, as shown in FIG. 8, the optimum correction amount is stored in a database, and based on the shape and size of the detected defect, the optimum correction amount of the defect is obtained from the database and correction is performed. Alternatively, as shown in FIG. 9, a simulation is performed for each defect detection without calculating the optimal correction amount in a database, and the optimum correction amount is calculated.
[0046]
According to the mask defect repair method of the present embodiment described above, it becomes possible to repair the broken canopy of the eaves-type Levenson phase shift mask while appropriately controlling the light intensity balance. The mask defect repair method according to the present embodiment can efficiently repair a defect particularly when a plurality of eaves bent portions are detected.
[0047]
Embodiments of the mask and the mask defect repair method of the present invention are not limited to the above description. For example, instead of depositing the light-shielding material by sputtering in the second embodiment, other film forming methods such as physical vapor deposition (PVD) other than sputtering, such as vacuum deposition, and molecular beam epitaxy (MBE) are used. A light-shielding material layer may be formed. In addition, various changes can be made without departing from the spirit of the present invention.
[0048]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to the mask of this invention, even if a defect arises in the eaves part of a phase shift mask, it becomes possible to use it, without recreating a mask.
According to the mask defect repairing method of the present invention, when the eaves is broken by the eaves type Levenson phase shift mask, the mask can be repaired to be usable.
[Brief description of the drawings]
FIGS. 1A and 1B are cross-sectional views illustrating a manufacturing process of an eaves-type Levenson phase shift mask according to Embodiments 1 and 2 of the present invention.
FIGS. 2 (c) to 2 (e) are cross-sectional views showing a step that follows the step of FIG. 1 (b).
FIGS. 3A and 3B relate to the first embodiment of the present invention, wherein FIG. 3A is a cross-sectional view of a normal eaves-type Levenson phase shift mask, and FIG. 3B is a view showing a result of the electromagnetic field simulation of FIG.
4A and 4B relate to the first embodiment of the present invention, wherein FIG. 4A is a cross-sectional view of an eaves-type Levenson phase shift mask having a bent eaves portion, and FIG. 4B is a view showing the result of the electromagnetic field simulation of FIG. It is.
5A and 5B relate to the first embodiment of the present invention, in which FIG. 5A is a cross-sectional view of an eaves-type Levenson phase shift mask in which an eaves-bent portion is restored, and FIG. 5B shows the result of the electromagnetic field simulation of FIG. FIG.
FIG. 6 is a diagram collectively showing the simulation results of FIGS. 3 (b), 4 (b) and 5 (b).
FIG. 7 is a schematic view of an apparatus for depositing a light-shielding material layer at a defective portion according to the first embodiment of the present invention.
FIG. 8 is a diagram showing a defect correction flow according to the first and second embodiments of the present invention.
FIG. 9 is a diagram showing a defect correction flow according to the first and second embodiments of the present invention.
FIGS. 10A and 10B are cross-sectional views showing steps of a mask defect repair method according to the second embodiment of the present invention.
FIGS. 11C and 11D are cross-sectional views showing a step that follows the step shown in FIG. 10B.
12A is a cross-sectional view of a quartz (Qz) digging type Levenson phase shift mask, and FIG. 12B is a diagram showing a result of the electromagnetic field simulation of FIG.
13A is a cross-sectional view of a dual trench type Levenson phase shift mask, and FIG. 13B is a diagram illustrating a result of the electromagnetic field simulation of FIG.
14A is a cross-sectional view of a shifter width bias type Levenson phase shift mask, and FIG. 14B is a diagram illustrating a result of the electromagnetic field simulation of FIG.
15A is a cross-sectional view of an eaves-type Levenson phase shift mask, and FIG. 15B is a diagram showing a result of the electromagnetic field simulation of FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Quartz (Qz) board | substrate, 2 ... Light shielding film, 3 ... Light transmission part, 4 ... Resist, 5 ... Shifter part, 6 ... Non-shifter part, 7 ... Eaves part, 8 ... Eaves breaking part, 9 ... Light shielding material layer , 11 nozzle, 12 organic gas, 13 Ga ion beam, 14 carbon film, 16 defect location, 17 resist pattern (top view), 18 resist, 19 chromium, 21 Qz substrate, 22 , A light shielding film, 23, a light transmitting portion, 24, a shifter portion, 25, a first shifter portion, 26, a second shifter portion, 27, an eave portion.

Claims (8)

At least one first light transmitting region that is part of the light transmitting substrate;
In at least one second light transmitting region that is another part of the light transmitting substrate, a phase of transmitted light of a predetermined wavelength is inverted from a phase of transmitted light of the first light transmitting region. A second light transmitting region formed thinner than the first light transmitting region;
A light-shielding film formed on the light-transmitting substrate other than the first and second light-transmitting regions;
An edge portion of the light-shielding film around the second light transmission region, an extended portion extended on the second light transmission region,
Adjusting the distribution of transmitted light intensity of the first light transmitting region and the second light transmitting region formed in a part of the second light transmitting region following the edge or the extended portion. A light-shielding material layer having a predetermined width. At least one first light transmitting region that is part of the light transmitting substrate;
In at least one second light transmitting region that is another part of the light transmitting substrate, a phase of transmitted light of a predetermined wavelength is inverted from a phase of transmitted light of the first light transmitting region. A second light transmitting region formed thinner than the first light transmitting region;
A light-shielding film formed on the light-transmitting substrate other than the first and second light-transmitting regions;
Detecting, in a mask having an extended portion extending above the second light transmitting region, an edge of the light-shielding film around the second light transmitting region, detecting a defective portion where the extended portion is lost; Analyzing the shape and size of the location;
A predetermined width for forming a light-shielding material layer on a part of the second light transmitting region continuously with the edge or the extended portion, wherein the first light transmitting region and the second light transmitting region Determining the predetermined width to reduce the difference in transmitted light intensity according to the shape and size of the defective portion;
Forming the light shielding material layer with the predetermined width. The step of determining the predetermined width is a step of performing a first simulation of calculating a distribution of transmitted light intensity and a pattern to be transferred under a plurality of conditions in which the shape and size of a defective portion and the width of the light shielding material layer are different in advance. When,
Creating a database from the results of the first simulation;
3. The method according to claim 2, further comprising: comparing a shape and a size of the defective portion detected by the mask with the database and selecting the predetermined width from the database. The shape and size of the defective portion detected by the mask are compared with the database, and when not registered in the database, using the shape and size of the defective portion detected by the mask, Performing a second simulation for calculating the distribution of transmitted light intensity and the pattern to be transferred under a plurality of conditions in which the width of the light shielding material layer is different;
4. The method according to claim 3, further comprising: determining the predetermined width from the result of the second simulation. The step of determining the predetermined width includes, using a shape and a size of the defect portion detected by the mask, under a plurality of conditions in which the width of the light shielding material layer is different, a pattern of a transmitted light intensity distribution and a pattern to be transferred. Performing a second simulation to calculate
Determining the predetermined width from the result of the second simulation. The method further comprises a step of determining that the simulation result is acceptable and that a defective portion is not required to be corrected,
3. The method according to claim 2, wherein the determination of the predetermined width and the formation of the light shielding material layer are performed at a defective portion where the simulation result is not allowed. 3. The method according to claim 2, wherein forming the light shielding material layer includes irradiating a focused ion beam in the presence of an organic gas to deposit carbon. Forming the light-shielding material layer, a step of forming a resist on the light-transmitting substrate except for the light-shielding material layer forming region,
Sputtering using the resist as a mask to form the light-shielding material layer,
3. The method according to claim 2, further comprising: removing the resist.

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