JP2024009519A - Vapor deposition mask production method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress insufficient deposition and deposition of contaminants in deposition of an organic luminescent material.

SOLUTION: A vapor deposition mask production method in one embodiment includes a hole formation step of irradiating a composite material having a metal layer provided with multiple openings and a resin layer extending in contact with the metal layer with a laser beam from the metal layer side so as to a through-hole in a resin layer part exposed in the openings; and a removal step of removing debris on the metal layer by irradiating the composite material in which the through-hole has been formed with UV light from the metal layer side.

SELECTED DRAWING: Figure 3

COPYRIGHT: (C)2024,JPO&INPIT

Description

The present invention relates to a method for manufacturing a deposition mask.

A vapor deposition mask is used in the manufacture of organic EL elements. An organic EL element is created by depositing an organic light-emitting material at a predetermined position (that is, a portion that will become a pixel) on a substrate to be deposited. A deposition mask is used to deposit the organic light emitting material only on the pixel portions of the substrate to be deposited.

Vapor deposition masks have traditionally been made of metal. However, in order to produce higher-definition organic EL elements, it is necessary to reduce the thickness of the vapor deposition mask, and for this reason, it has been proposed to use, for example, a polyimide resin thin film instead of metal.

Specifically, a vapor deposition mask using a resin thin film is provided with a structure in which a resin thin film is laminated on a metal layer in which metal frames are arranged in a grid pattern (for example, see Patent Document 1). Through holes are formed in the resin thin film by irradiating laser light from the metal frame side. Such a vapor deposition mask is referred to herein as a thin film mask with a metal frame.

When depositing an organic light-emitting material onto a substrate to be vapor-deposited, a thin film mask with a metal frame is installed such that the thin resin film side faces the substrate to be vapor-deposited. By applying a magnetic force to the metal layer, the thin film mask with a metal frame is fixed onto the substrate to be deposited, and an organic light emitting material is deposited thereon. The organic light-emitting material is deposited on the deposition substrate only in the portion where the through-hole of the thin film mask with a metal frame is formed.

Japanese Patent Application Publication No. 2017-179591

However, when an organic light emitting material was deposited using a thin film mask with a metal frame that was actually created, the following phenomenon was observed.

(1) In the glass substrate, although the organic light-emitting material should be deposited at each location where the through-hole is formed in the resin thin film, there were cases where the organic light-emitting material was not sufficiently deposited.
(2) Substances (contaminants) other than organic light-emitting materials were sometimes deposited.
Therefore, an object of the present invention is to suppress the phenomena (1) and (2) above.

In order to solve the above problems, one embodiment of the vapor deposition mask manufacturing method according to the present invention includes a composite material having a metal layer provided with a plurality of openings and a resin layer that spreads in contact with the metal layer. A hole forming step in which a through hole is formed in the resin layer portion exposed in the opening by irradiating laser light from the layer side, and ultraviolet light is applied from the metal layer side to the composite material in which the through hole is formed. and a removal step of removing debris on the metal layer by irradiating with.

According to such a vapor deposition mask manufacturing method, resin debris generated by laser light in the hole forming process is removed from above the metal layer, so that the above-mentioned (1) ) and the phenomenon (2) above, which occurs when debris falls into the vapor deposition source (for example, a crucible) of the organic light-emitting material, are suppressed.

Debris is organic residue that is created when resin is ablated in an opening process using a laser. This slag is caused by the resin layer being heated and vaporized by the laser and scattered. The organic slag is mainly a hydrocarbon compound, but its molecular weight is smaller than that of the resin layer and has a wide range. Those with a small molecular weight fly away as a gas, but those with a large molecular weight solidify and accumulate near the opening made by the laser.
When the organic matter solidifies, it adheres to the surface of the metal frame in the form of tar, or solidifies in the air and accumulates on the surface of the metal frame. Debris does not have the same molecular structure as the original resin layer, so its absorption and decomposition characteristics for ultraviolet light are different from those of the resin layer. Specifically, since the resin layer is generally an aromatic compound and has a conjugated double bond structure, it is resistant to ultraviolet rays. This resistance provides selectivity in removing debris without damaging the resin layer.
It has not been previously known that the causes of the phenomena (1) and (2) above are debris on the metal layer, and this has now become clear for the first time as a result of intensive studies by the inventors of the present application.

In the vapor deposition mask manufacturing method, it is desirable that in the removal step, ultraviolet light from a xenon excimer lamp is used as the ultraviolet light. Since the xenon excimer lamp emits high-intensity ultraviolet light, debris can be sufficiently removed with short irradiation.

In the vapor deposition mask manufacturing method, it is also preferable that ultraviolet light from a low-pressure mercury lamp is used as the ultraviolet light in the removal step. Ultraviolet light from a low-pressure mercury lamp can reach farther in the air than ultraviolet light from a xenon excimer lamp. Therefore, the arrangement of the lamp and the composite material in the removal process is easy.

Further, in the vapor deposition mask manufacturing method, it is preferable that the removing step includes pre-cleaning of performing ultrasonic cleaning on the composite material after the through-hole is formed and before the ultraviolet light is irradiated. . By including pre-cleaning, the synergistic effect with debris removal by ultraviolet light irradiation can shorten the ultraviolet light irradiation time and ensure thorough debris removal.

Further, in the vapor deposition mask manufacturing method, the removing step preferably includes post-cleaning of ultrasonic cleaning the composite material after being irradiated with the ultraviolet light. By including post-cleaning, the ultraviolet light irradiation time can be shortened and debris removal can be thoroughly removed due to the synergistic effect with debris removal by ultraviolet light irradiation. Furthermore, since the pre-cleaning and the post-cleaning are thought to have different effects on debris, further synergistic effects are expected by performing both the pre-cleaning and the post-cleaning.

According to the present invention, the phenomena (1) and (2) above can be suppressed.

FIG. 1 is a schematic structural diagram of a vapor deposition mask (thin film mask with a metal frame) manufactured by the vapor deposition mask manufacturing method of the present invention. It is a figure which shows the vapor deposition process using a vapor deposition mask (thin film mask with a metal frame). FIG. 1 is a diagram showing a first embodiment of the vapor deposition mask manufacturing method of the present invention. It is a figure showing the state of debris. FIG. 3 is a diagram showing the influence of debris during vapor deposition. It is a figure showing an ultraviolet light irradiation device used for a debris removal process. It is a figure which shows the debris removal result in a debris removal process (dose amount of 10J/cm ^<2> ). It is a figure which shows the debris removal result in a debris removal process (dose amount of 20J/cm ^<2> ). It is a figure which shows the debris removal result in a debris removal process (dose amount of 40J/cm ^<2> ). It is a figure showing the result of debris removal by VUV irradiation. It is a figure which shows 2nd Embodiment in the vapor deposition mask manufacturing method of this invention. It is a figure which shows 3rd Embodiment in the vapor deposition mask manufacturing method of this invention. It is a table showing the debris removal results when ultraviolet light irradiation and ultrasonic cleaning are combined. FIG. 3 is a diagram schematically showing a test board.

Embodiments of the present invention will be described below based on the drawings. However, in order to avoid the following explanation from becoming unnecessarily redundant and to facilitate understanding by those skilled in the art, more detailed explanation than necessary may be omitted. For example, detailed explanations of well-known matters or redundant explanations of substantially the same configurations may be omitted. Further, elements shown in the previously described figures may be appropriately referred to in the explanation of later figures.

FIG. 1 is a schematic structural diagram of a vapor deposition mask (thin film mask with a metal frame) manufactured by the vapor deposition mask manufacturing method of the present invention.
FIG. 1 shows a cross-sectional view (A) and a plan view (B) of a thin film mask 100 with a metal frame.
The thin film mask 100 with a metal frame has a grid-shaped metal frame 102 in which a large number of openings 102a are provided. The metal frame 102 is made of nickel, for example, and corresponds to an example of the metal layer according to the present invention. The thickness of the metal frame 102 (size in the vertical direction in the cross-sectional view (A)) is, for example, about 30 μm.

The thin film mask 100 with a metal frame has a resin thin film 101 overlaid on a metal frame 102, and the thin film 101 is provided with a through hole 103 connected to an opening 102a of the metal frame 102. The thin film 101 is made of polyimide (PI) or polyethylene terephthalate (PET), for example. The following description will be made assuming that the thin film 101 is made of polyimide as an example. The size of the through hole 103 is, for example, about 20 μm, and the thickness of the thin film 101 is, for example, about 10 μm.

The width of the thin film mask 100 with a metal frame is larger than the width of the screen of the organic EL element, and the thin film mask 100 with a metal frame may have an outer frame 104 to improve strength. The outer frame 104 is made of metal and has a thickness of, for example, about 20 mm (size in the vertical direction in the cross-sectional view (A)).
FIG. 2 is a diagram showing a vapor deposition process using a vapor deposition mask (a thin film mask with a metal frame).
A stage 202, a deposition source 203, and a heat source 205 are provided in the deposition chamber 200.
The stage 202 has a built-in magnetic chuck. The vapor deposition source 203 is, for example, a crucible, on which an organic light emitting material 204 is placed and heated by a heat source 205 .

A glass substrate (substrate to be evaporated) 201 and a thin film mask 100 with a metal frame are placed below the stage 202 with the glass substrate 201 sandwiched between the stage 202 and the thin film mask 100 with a metal frame. The thin film mask 100 with a metal frame is attached to the glass substrate 201 with the polyimide thin film 101 facing the glass substrate 201 side (with the metal frame 102 facing the evaporation source 203 side).

The metal frame 102 of the thin film mask 100 with a metal frame is attracted toward the stage 202 by the magnetic force of the magnetic chuck of the stage 202, and the thin film mask 100 with a metal frame is held on the stage 202 with the glass substrate 201 in between. Fixed. The glass substrate 201 is also pressed against the stage 202 by the thin film mask 100 with a metal frame, and is held and fixed on the stage 202. Although not shown, a minute spacer is provided between the glass substrate 201 and the thin film mask 100 with a metal frame to prevent the glass substrate 201 and the thin film 101 from coming into close contact with each other.

The organic light emitting material 204 of the evaporation source 203 is heated while the glass substrate 201 and the thin film mask 100 with a metal frame are held and fixed on the stage 202, and the vaporized organic light emitting material 204 rises toward the glass substrate 201. Then, the organic light-emitting material 204 is deposited on the surface of the glass substrate 201 on a portion of the surface of the glass substrate 201 that is not covered with the thin film 101 of the thin film mask 100 with a metal frame (the portion of the through hole 103).

FIG. 3 is a diagram showing a first embodiment of the vapor deposition mask manufacturing method of the present invention.
FIG. 3 shows a base material forming step (A), a hole forming step (B), and a debris removing step (C), and further shows an intermediate state (B') after the hole forming step (B). ) and the final state (C') after the debris removal step (C) are also shown.

In the base material forming step (A), a thin resin film 111 is formed on the metal frame 102 to form a base material 110 without through holes. The base material 110 corresponds to an example of a composite material according to the present invention.

In the hole forming step (B), the thin film 111 exposed at the opening 102a of the metal frame 102 is irradiated with the laser beam L1 from the metal frame 102 side, and the through hole 103 is formed by the laser beam L1. The pore forming step (B) corresponds to an example of the pore forming step according to the present invention.

In the base material 110 in the intermediate state (B'), a through hole 103 is formed in the thin film 101, and debris 300 is attached to the surface (at least one of the top surface and the side surface) of the metal frame 102. This debris 300 is polyimide residue that did not decompose and evaporate when forming the through hole 103 using a laser and adhered to the surface of the metal frame 102.
Here, the debris 300 on the surface of the metal frame 102 will be explained.

FIG. 4 is a diagram showing the state of the debris 300.
FIG. 4 schematically shows a state in which a sample corresponding to the base material 110 in the intermediate state (B') in FIG. 3 is observed and confirmed using a SEM (Scanning Electron Microscope). .

FIG. 4 shows a part of the metal frame 102 in an enlarged manner, and shows that debris 300 is attached to the surface of the metal frame 102 extending in the vertical direction in the figure. The debris 300 completely covers the surface of the metal frame 102, and the surface of the debris 300 is fluffy.
FIG. 5 is a diagram showing the influence of debris 300 during vapor deposition.

Part of the debris 300 on the surface of the metal frame 102 (especially the fluffy part) peels off when it is heated in the vapor deposition pot 200 , and the lifted debris 300 attaches to the thin film 101 and partially covers the through hole 103 . The debris 300 that is blocked or fallen is mixed into the organic light emitting material 204 of the evaporation source 203 .

The debris 300 that partially blocks the through-hole 103 impedes the deposition of the organic light-emitting material 204, resulting in (1) a portion of the glass substrate 201 that is not sufficiently deposited;

Further, the debris 300 that has fallen into the deposition source 203 is deposited on the glass substrate 201 together with the organic light emitting material 204, and (2) substances (contaminants) other than the organic light emitting material are deposited on the glass substrate 201.

The fact that the cause of the phenomena (1) and (2) above is the debris 300 is a fact that was revealed for the first time by the inventors of the present application after intensive study of the phenomena (1) and (2) above. be. The inventors of the present application have diligently studied the phenomena (1) and (2) above, and have discovered that foreign matter (debris 300) is attached to the surface of the metal frame 102. The inventors further investigated and found that this foreign material was a residue of polyimide that did not decompose and evaporate when the through hole 103 was formed using a laser. As a result of further consideration, it was realized that the phenomena (1) and (2) above occur due to the above-mentioned effects of the fallen debris 300 and the flying debris 300.

Therefore, in an embodiment of the deposition mask manufacturing method shown in FIG. 3, the debris removal step (C) is performed on the base material 110 in the intermediate state (B') to remove the debris 300. That is, in the debris removal step (C) in FIG. 3, the ultraviolet light L2 is irradiated onto the base material 110 from the metal frame 102 side, and the debris 300 is removed. The debris removal step (C) corresponds to an example of the removal step according to the present invention.

The ultraviolet light L2 used in the debris removal step (C) includes vacuum ultra-violet light (VUV) that has a peak wavelength of 172 nm emitted from a xenon excimer lamp, and 185 nm wavelength emitted from a low-pressure mercury lamp. Preferred ultraviolet light is ultra-violet light (UV) having a peak at a wavelength of 254 nm. Among these ultraviolet lights, ultraviolet light with a wavelength of 200 nm or less is particularly suitable for use in the debris removal step (C).
By using a diffused light source such as the above-mentioned xenon excimer lamp or low-pressure mercury lamp, when the ultraviolet light L2 is irradiated onto the base material 110 from the metal frame 102 side, the debris 300 on the side surface of the metal frame 102 is also removed. Ru.
FIG. 6 is a diagram showing an ultraviolet light irradiation device used in the debris removal process.
The ultraviolet light irradiation device 400 includes a housing 401 , an ultraviolet light irradiator 402 , a linear cylinder device 404 , and a stage 406 .

A light source 403 is mounted on the ultraviolet light irradiator 402, and the ultraviolet light irradiator 402 is installed in the upper part of the housing 401, and the lower part is open. The ultraviolet light irradiator 402 irradiates the ultraviolet light emitted from the light source 403 downward.

The linear cylinder device 404 is installed in the lower part of the housing 401, and includes a cylinder portion 404a, a drive portion 404b, and a pedestal portion 404c.
The pedestal part 404c is installed in a part of the entire length of the cylinder part 404a, and is movable in the left-right direction in the figure with respect to the cylinder part 404a.

The cylinder portion 404a is provided with a ball screw (not shown) therein, and the ball screw is driven by the driving portion 404b, so that the pedestal portion 404c moves horizontally and accurately at a predetermined speed.

A stage 406 is fixed to the pedestal portion 404c via a support 405. A workpiece W, which is the base material 110 described above, is placed on the stage 406, and the stage 406 and the workpiece W pass below the ultraviolet light irradiator 402 as the pedestal portion 404c moves. As shown in FIG. 6, the pedestal portion 404c completely passes under the ultraviolet light irradiator 402, so that the ultraviolet light from the light source 403 is uniformly irradiated from one end of the workpiece W to the other.

By passing through the debris removal step (C) shown in FIG. 3 in which the ultraviolet light irradiation device 400 was used, the debris 300 was removed from the metal frame 102 in the finished state (C') after the debris removal step (C). A thin film mask 100 with a metal frame is obtained. Note that the removal of the debris 300 in the debris removal step (C) is not limited to complete removal of the debris 300 from the metal frame 102, but removes the debris 300 to the extent that the phenomena (1) and (2) above are sufficiently suppressed. should be removed.
When the resin thin film 101 is made of at least one of polyimide (PI) and polyethylene terephthalate (PET), it not only has suitable properties required for a mask material, such as heat resistance, tensile strength, bending elasticity, and coefficient of thermal expansion. , the decomposition rate of debris 300 by vacuum ultraviolet rays is high, and it is excellent as a mask material.

7 to 9 are diagrams showing the results of debris removal in the debris removal step (C).
7 to 9 show, as an example, the results of debris removal by UV irradiation using a low-pressure mercury lamp. 7 to 9 schematically show states confirmed by SEM observation.
Further, FIG. 7 shows the results of irradiation with ultraviolet light at a dose of 10 J/cm ² , and FIG. 8 shows the results of irradiation with ultraviolet light at a dose of 20 J/cm ² . FIG. 9 shows the results of irradiation with ultraviolet light at a dose of 40 J/cm ² .

With a low-pressure mercury lamp, a dose of 10 J/cm ² requires approximately 30 minutes of irradiation time, a dose of 20 J/cm ² requires approximately 1 hour, and a dose of 40 J/cm ² requires approximately 30 minutes of irradiation time. It requires 2 hours of irradiation time.

In the state shown in FIG. 7, although much debris 300 remains on the surface of the metal frame 102, most of the fluffy debris 300 has been removed and the surface of the debris 300 has become smooth. Therefore, peeling off of the debris 300 during vapor deposition is significantly suppressed, and the phenomena (1) and (2) above are also suppressed.
In the state shown in FIGS. 8 and 9, the amount of debris 300 has decreased significantly, and the debris 300 has been removed to the extent that the linear shape of the metal frame 102 is visible.

FIG. 10 is a diagram showing the results of debris removal by VUV irradiation from an excimer lamp.
FIG. 10 schematically shows the state confirmed by SEM observation.
FIG. 10 shows the result (A) of debris removal by VUV irradiation (that is, VUV irradiation at a dose that is contrasted with the dose in UV irradiation), which is compared with the debris removal by UV irradiation shown in FIG. The results of debris removal by VUV irradiation (B), which is compared with the debris removal by UV irradiation shown in Figure 8, and the results of debris removal by VUV irradiation, which is compared with the debris removal by UV irradiation, shown in Figure 9 (C) are shown. .

At any dose amount, the results of debris removal by VUV irradiation (A), (B), and (C) are similar to the results of debris removal by UV irradiation shown in FIGS. 7 to 9. However, since VUV irradiation uses a xenon excimer lamp to obtain high illuminance, the irradiation time is about several minutes to several tens of minutes, which is shorter than UV irradiation.

On the other hand, in the case of UV irradiation, since ultraviolet light from a low-pressure mercury lamp is used, the distance that ultraviolet light can reach in the air is longer than that of ultraviolet light from a xenon excimer lamp. Therefore, in the ultraviolet light irradiation apparatus 400 shown in FIG. 6, it is preferable that the distance between the workpiece W (and stage 406) and the ultraviolet light irradiator 402 can be provided with some margin. Particularly, in manufacturing the thin film mask 100 with a metal frame having the outer frame 104 shown in FIG. 1, it is possible to irradiate ultraviolet light through the outer frame 104 without bringing the light source close to each other, which is suitable.

Next, another embodiment of the vapor deposition mask manufacturing method of the present invention will be described.
FIG. 11 is a diagram showing a second embodiment of the vapor deposition mask manufacturing method of the present invention.
In the second embodiment, an ultraviolet light irradiation step (C1), which is a step similar to the debris removal (C) described above, is performed, and between the hole formation step (B) and the ultraviolet light irradiation step (C1) described above. A pre-cleaning step (C2) is performed. In the case of the second embodiment, the combined process of the ultraviolet light irradiation process (C1) and the pre-cleaning process (C2) corresponds to an example of the removal process according to the present invention.
In the pre-cleaning step (C2), ultrasonic cleaning is performed on the base material 110 that has undergone the hole-forming step (B). That is, the base material 110 is immersed in a cleaning solution 501 and ultrasonic waves 502 are applied. At this time, the frequency of the ultrasonic waves 502 is set to a frequency of 80 to 1000 kHz, preferably 80 to 200 kHz, in order to protect the thin film 101 of the base material 110. Ultrasonic cleaning using the ultrasonic waves 502 set at the above frequency has a weak cleaning power, and the debris 300 cannot be sufficiently removed by ultrasonic cleaning alone. However, as will be described later, it was confirmed that by going through a short pre-cleaning step (C2), the ultraviolet light irradiation time and thorough debris removal in the subsequent ultraviolet light irradiation step (C1) can be shortened. Ta.
The reason for this is that the debris 300 is polyimide residue that did not decompose and evaporate when forming the through hole 103 using a laser and adhered to the surface of the metal frame 102, and the form of this adhesion is as shown in FIG. This has led to various forms of adhesion ranging from fluff to fine granules to tar. In the pre-cleaning step (C2), as mentioned above, the cleaning power of ultrasonic cleaning is weak, but it is effective in acting on and removing the fluffy parts of debris, and when the fluffy parts are removed, there are fewer areas that are shaded by the light. This is because the ultraviolet light becomes more likely to reach the surface of the attached debris in the form of fine granules or tar. If the frequency of the ultrasonic waves 502 exceeds 1000 kHz, the cleaning effect will be low and the processing time will be significantly longer, requiring several hours or more, which is not economical as a mask manufacturing method. When the frequency exceeded 200 kHz, the time required for cleaning increased from 2 minutes to even longer.

FIG. 12 is a diagram showing a third embodiment of the vapor deposition mask manufacturing method of the present invention.
In the third embodiment, a post-cleaning step (C3) is performed after the above-described hole forming step (B) and ultraviolet light irradiation step (C1). In the case of the third embodiment, the combined process of the ultraviolet light irradiation process (C1) and the post-cleaning process (C3) corresponds to an example of the removal process according to the present invention.
In the post-cleaning step (C3), ultrasonic cleaning is performed on the base material 110 that has undergone the ultraviolet light irradiation step (C1). That is, similarly to the pre-cleaning step (C2), the base material 110 is immersed in a cleaning solution 501 and ultrasonic waves 502 are applied. Also in the post-cleaning step (C3), the frequency of the ultrasonic wave 502 is set at a frequency of 80 to 1000 kHz in order to protect the thin film 101 of the base material 110, and preferably a frequency of 80 to 200 kHz, so that the cleaning power is improved. Although weak, as will be described later, by combining the short post-cleaning step (C3) with the ultraviolet light irradiation step (C1), the ultraviolet light irradiation time in the ultraviolet light irradiation step (C1) can be shortened, It was confirmed that debris was thoroughly removed in the finished state after the post-cleaning step (C3). The reason for this is that irradiation with ultraviolet light causes a photochemical effect on the debris, which reduces the molecular weight of the debris itself and makes it easier to dissolve.The other reason is that the surface of the debris is photo-modified, making it less soluble with the cleaning solution. This is because the cleaning solution can more easily penetrate into the intricately deposited debris, eliminating air bubbles and increasing the transmittance of ultrasonic waves, thereby increasing the cleaning effect. As described above, the pre-cleaning step and the post-cleaning step have different effects on debris removal depending on the combination with the ultraviolet light according to the present invention. When the frequency of the ultrasonic wave 502 exceeds 1000 kHz, the cleaning effect becomes low and the processing time becomes significantly longer, requiring several hours or more, which is not economical as a mask manufacturing method. When the frequency exceeded 200 kHz, the time required for cleaning increased from 5 minutes to even longer.

FIG. 13 is a table showing the debris removal results when ultraviolet light irradiation and ultrasonic cleaning are combined.
FIG. 13 shows the results of VUV irradiation as an example of ultraviolet light irradiation. Additionally, there is a column 601 for the case of VUV irradiation only (hereinafter referred to as the VUV irradiation only column 601), and a column 602 for the case where VUV irradiation is performed after ultrasonic cleaning (hereinafter referred to as the pre-ultrasonic cleaning column 602). ), and a column 603 for when ultrasonic cleaning is performed after VUV irradiation (hereinafter referred to as post-ultrasonic cleaning column 603), the removal results in each debris removal procedure are shown. The object to be removed in each debris removal procedure shown in FIG. 13 is a test substrate corresponding to the base material 110 in the above-described embodiment.

FIG. 14 is a diagram schematically showing a test board.
The test substrate 610 has a formation region R1 in which a large number of through holes 103 (not shown) are formed through the same steps as the base material forming step (A) and the hole forming step (B) in FIG. It has a non-formation region R2 where the hole 103 is not formed.

FIG. 14 shows a test substrate 610 in an untreated state (A) in which neither ultrasonic cleaning nor VUV irradiation has been performed, a state in which debris has been removed (B), and a state in which debris has not been removed (B). A state (C) in which further removal has been performed and a completely removed state (D) in which the debris 300 is completely removed by debris removal are shown.

Since debris 300 adheres to the metal frame 102 (not shown) in the formation region R1 of the substrate 610, there is a large contrast (difference in brightness and darkness) between the formation region R1 and the non-formation region R2 in the state (A) where debris has not been removed. ) occurs. On the other hand, in the states (B) and (C) where debris has been removed, the contrast between the formation region R1 and the non-formation region R2 is small, and in the complete removal state (D), the contrast between the formation region R1 and the non-formation region R2 is The contrast with that is zero.
In the table of FIG. 13, the removal rate based on the contrast between the formation region R1 and the non-formation region R2 is listed as a numerical value representing the result of debris removal.

The removal rate is the value obtained by subtracting from 100 the percentage of the ratio of the average value of the numerical contrast on the surface of the substrate 610 after debris removal divided by the average value of the numerical value of the contrast on the surface of the substrate 610 before debris removal. It is. That is, as for the removal rate, 0% represents a state in which debris has not been removed, and 100% represents a state in which debris has been completely removed.

Each row in Figure 13 corresponds to VUV irradiation at each dose [J/cm ² ] shown on the left end of the table, and the row with a dose of 0 J/cm ² shows the results of debris removal only by ultrasonic cleaning. represents. Referring to the post-ultrasonic cleaning column 603, ultrasonic cleaning for 1 minute at 80kHz results in a removal rate of 5%, and ultrasonic cleaning for 2 minutes results in a removal rate of 7%, but ultrasonic cleaning for 5 minutes or more It has been shown that the removal rate does not increase from 7% even if the coating is applied. It has been confirmed that with only ultrasonic cleaning at 80 kHz, the removal rate remains unchanged even after 20 hours or more. Moreover, with such a low removal rate, the removal of the fluffy debris 300 shown in FIG. 4 is also insufficient, and the phenomena (1) and (2) described above are not suppressed.

On the other hand, referring to the VUV only column 601, a high removal rate of 35% was obtained even at a dose of 7 J/cm ² , and it was confirmed that at least the fluffy debris 300 was removed.

When the dose amount is 7 J/ ^cm2 , comparing the VUV irradiation only column 601 with the pre-ultrasonic cleaning column 602 and post-ultrasonic cleaning column 603, it is found that the VUV irradiation only column 601 has a removal rate of 35%. On the other hand, in the front ultrasonic cleaning column 602, a high removal rate of 57% was obtained with a short time of 1 minute of ultrasonic cleaning at 80 kHz, and in the post ultrasonic cleaning column 603, a removal rate of 67% was obtained with a short time of 1 minute of ultrasonic cleaning at 80 kHz. It has been shown that even greater removal rates of % can be obtained. In other words, by combining ultraviolet light irradiation and ultrasonic cleaning, a debris removal effect that greatly exceeds the sum of the individual debris removal results can be obtained, and thorough cleaning can be achieved even in a short debris removal time. It has been shown that

Referring to the debris removal results in which the removal rate reaches 60% or more, in the VUV irradiation only column 601, it is 65% when the dose is 14 J/cm ² , whereas in the pre-ultrasonic cleaning column 602, it is 65% when the dose is 14 J/cm2. When the cleaning and dose amount is 7 J/cm ² , it reaches 60%, and in the post ultrasonic cleaning column 603, the ultrasonic cleaning for 1 minute and the dose amount reaches 67% when it is 7 J/cm ² . In other words, by combining ultraviolet light irradiation and ultrasonic cleaning, in order to obtain the same debris removal effect as debris removal alone, the total time of ultraviolet light irradiation and ultrasonic application is longer than when debris removal is performed alone. It has been shown that it takes only a short time.

Note that the effect of the pre-cleaning step (C2) shown in FIG. 11 on debris removal is considered to be different from the effect of the post-cleaning step (C3) shown in FIG. 12 on debris removal. It is expected that further time reduction and thoroughness will be achieved by performing both C2) and post-cleaning step (C3).
Next, for the substrate 610 having the thin film 101 made of each of PI and PET, the debris removal rate until the removal rate reached 100% was determined in a test equivalent to the test described above. Evaluation was made by comparing with the substrate 610. The debris removal rate on the substrate 610 using PI and PET was higher than the debris removal rate on the substrate 610 using other resins, 5 times in the case of PI and 3 times in the case of PET. The inventors have revealed that the following mechanism operates in PI and PET.
When the resin debris 300 is decomposed with vacuum ultraviolet rays, the debris 300 reacts with surrounding ozone and radicals, becomes carbon dioxide and water molecules, and evaporates. That is, when the resin is decomposed by vacuum ultraviolet rays, a large amount of water molecules are present in the surrounding area, so some of them are adsorbed to the resin constituting the thin film 101.
When PET and PI are irradiated with vacuum ultraviolet rays, they are in a high energy state due to the conjugated bond state inside the resin due to absorption of the vacuum ultraviolet rays. When water molecules come into contact with it, an energy transition occurs, and the water molecules adsorbed on the surface are decomposed again by vacuum ultraviolet rays, becoming hydroxyl radicals (OH radicals) and being released. Adsorption and decomposition of water molecules occur on the thin film 101, and OH radicals have extremely high reactivity, but since the molecular structures of the resins of the thin film 101 and the debris 300 are different, the decomposition of the material of the thin film 101 is more The decomposition of debris 300 on the surface of 102 proceeds faster, assisting in the removal of debris 300.
Due to such a mechanism, debris 300 is removed more efficiently with PET and PI than with other resins, and therefore at least one of PET and PI is preferable as the material for the thin film 101.

100...Thin film mask with metal frame (evaporation mask), 102...Metal frame,
102a...Opening, 101, 111...Thin film, 103...Through hole, 104...Outer frame,
110... Base material, 200... Vapor deposition head, 201... Glass substrate, 203... Vapor deposition source,
204...organic light emitting material, 300...debris, 400...ultraviolet light irradiation device,
403...Light source, 501...Solution, 502...Ultrasonic wave, W...Work

Claims (7)

A composite material having a metal layer provided with a plurality of openings and a resin layer that spreads in contact with the metal layer is irradiated with a laser beam from the metal layer side, and the portion of the resin layer exposed within the openings is exposed. a hole forming step of forming a through hole;
a removal step of removing debris on the metal layer by irradiating the composite material in which the through hole is formed with ultraviolet light from the metal layer side;
A method for producing a vapor deposition mask, which comprises: 2. The vapor deposition mask manufacturing method according to claim 1, wherein in the removing step, ultraviolet light having a wavelength of 200 nm or less is used as the ultraviolet light. 3. The vapor deposition mask manufacturing method according to claim 2, wherein in the removing step, ultraviolet light from a xenon excimer lamp is used as the ultraviolet light having a wavelength of 200 nm or less. 3. The vapor deposition mask manufacturing method according to claim 2, wherein in the removing step, ultraviolet light from a low-pressure mercury lamp is used as the ultraviolet light having a wavelength of 200 nm or less. 2. The vapor deposition mask manufacturing method according to claim 1, wherein the resin layer is made of at least one of polyimide and polyethylene terephthalate. The vapor deposition according to claim 1, wherein the removing step includes pre-cleaning of performing ultrasonic cleaning on the composite material after the through-hole is formed and before the ultraviolet light is irradiated. Mask manufacturing method. 2. The vapor deposition mask manufacturing method according to claim 1, wherein the removing step includes post-cleaning of performing ultrasonic cleaning on the composite material after being irradiated with the ultraviolet light.

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