Evaporation mask and method for manufacturing electronic devices

Abstract

The object of the present invention is to provide a vapor deposition mask capable of forming vapor-deposited films with excellent pattern dimensions, and a method for manufacturing electronic devices using the vapor deposition mask. The vapor deposition mask of the present invention has a first surface and a second surface opposite to the first surface, and is formed with a plurality of openings penetrating between the first surface and the second surface. The mask is characterized in that protrusions extending from the first surface to the second surface are formed on the sidewalls of the openings, and the protrusion ratio of the protrusions relative to the opening width of the openings is 0.001 to 0.018.

Description

Technical Field

[0001] This invention relates to vapor deposition masks and methods for manufacturing electronic devices. Background Technology

[0002] For example, vapor deposition masks are known for being used in the fabrication of organic EL displays for the separation of RGB three colors.

[0003] Patent document 1 describes a vapor-deposited mask with a mask pattern formed on a silicon layer. It discloses that the mask pattern is formed by etching.

[0004] Patent document 2 describes a vapor deposition mask with multiple pixel openings. It discloses forming the pixel openings by etching.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Korean Patent No. 10-2358269

[0008] Patent Document 2: Japanese Patent Application Publication No. 2022-175925 Summary of the Invention

[0009] The problem that the invention aims to solve

[0010] Due to the uneven shape of the sidewall of the opening, the vapor-deposited material will accumulate on the sidewall, resulting in the problem of deterioration of the pattern size of the vapor-deposited film.

[0011] The object of the present invention is to provide a vapor deposition mask capable of forming vapor deposition films with excellent pattern dimensions, and a method for manufacturing electronic devices using the vapor deposition mask.

[0012] Methods for solving problems

[0013] The vapor deposition mask of this embodiment is a vapor deposition mask having a first surface and a second surface opposite to the first surface, and having a plurality of openings extending between the first surface and the second surface. The mask is characterized in that a protruding strip extending from the first surface to the second surface is formed on the sidewall of the opening, and the protrusion ratio of the protruding strip relative to the opening width of the opening is 0.001 or more and 0.018 or less.

[0014] The effects of the invention

[0015] According to the present invention, by controlling the protrusion ratio of the protrusions formed on the sidewalls of the openings of the vapor deposition mask, a vapor deposition film with excellent pattern dimensions can be stably formed. Furthermore, the cleaning frequency of the vapor deposition mask can be reduced, making quality management of the vapor deposition mask easier. Additionally, the occurrence of opening blockage can be reduced, enabling a longer lifespan for the vapor deposition mask. Attached Figure Description

[0016] [ Figure 1 [Illustration 1] is a cross-sectional view showing an example of the vapor deposition mask of this embodiment.

[0017] [ Figure 2 [] is an enlarged plan view of the opening.

[0018] [ Figure 3 [This is an enlarged front view of the side wall surface revealed by cutting open the section.]

[0019] [Figure 4] Figure 4A This is a SEM image showing the reference for measuring the protrusion size of the protrusion. Figure 4B This is a schematic diagram.

[0020] [Figure 5] Figure 5A This is an SEM image showing a magnified portion of the opening. Figure 5B This is a schematic diagram.

[0021] [Figure 6] Figures 6A-6E This is a schematic diagram illustrating the method for calculating the opening width.

[0022] [Figure 7] Figure 7A It is an SEM image of the sidewall of the opening. Figure 7B This is a schematic diagram.

[0023] [ Figure 8 [Illustration] is a schematic diagram showing the state of vapor-deposited material deposited on the sidewall of the opening.

[0024] [Figure 9] is a process diagram illustrating an example of a method for manufacturing a vapor deposition mask according to this embodiment.

[0025] [Figure 10] is a process diagram illustrating an example of a method for manufacturing a vapor deposition mask according to this embodiment.

[0026] [ Figure 11 [Illustration 1] is a cross-sectional view showing a method for manufacturing an electronic device using the vapor deposition mask of this embodiment.

[0027] [ Figure 12 [Illustration 1] is a cross-sectional view showing an example of a vapor deposition mask according to another embodiment.

[0028] [ Figure 13 [Illustration 1] is a cross-sectional view showing an example of a vapor deposition mask according to another embodiment.

[0029] [ Figure 14 [Illustration 1] is a cross-sectional view showing an example of a vapor deposition mask according to another embodiment.

[0030] [ Figure 15[Illustration 1] is a cross-sectional view showing an example of a vapor deposition mask according to another embodiment. Detailed Implementation

[0031] Hereinafter, embodiments will be described with reference to the accompanying drawings. However, the drawings are schematic or conceptual, and the dimensions and ratios of each drawing may not be the same as the actual situation. Furthermore, even when the drawings represent the same parts, the dimensional relationships and ratios may sometimes differ. In particular, the embodiments shown below exemplify structures used to embody the technical concept of the present invention, rather than specifically specifying the technical concept of the present invention. It should be noted that in the following description, elements having the same function and structure are labeled with the same symbols, and repeated descriptions are omitted. Additionally, the lower and upper limits of the numerical range include the error range. Furthermore, the "~" symbol includes both the lower and upper limits.

[0032] <The Process of Invention>

[0033] It is known that vapor deposition masks are used in OLED display manufacturing for the separation of RGB three colors, and the demand for vapor deposition masks for RGB separation is gradually increasing.

[0034] Evaporation masks have multiple openings corresponding to the evaporation film. In order to improve the pattern size of the evaporation film, the opening accuracy of the evaporation mask is important.

[0035] A vapor deposition mask is positioned between the substrate to be vaporized and the vapor deposition source. The vapor deposition material travels from the vapor deposition source through the opening of the vapor deposition mask to the surface of the substrate. If the vapor deposition material accumulates on the sidewalls of the opening, the opening width will be narrower than the actual width, making it difficult to form a vapor deposition film with excellent pattern dimensions.

[0036] Figure 8 This diagram shows the vapor-deposited material 12 deposited on the sidewall surface 52 of the opening 51 formed in the thin film 50. Thus, the deposition of the vapor-deposited material 12 on the sidewall surface 52 of the opening 51 creates a shadowing effect.

[0037] In the manufacturing of high-resolution OLED display devices, shading effects reduce the pattern size of the vapor-deposited film. Moreover, the reduction in pattern size affects the performance of the device, becoming a limiting factor for the resolution of OLED microdisplay devices.

[0038] The inventors conducted in-depth research and discovered that by focusing on the steps of the longitudinal stripes (protrusions) generated on the sidewall surface when the vapor-deposited material is deposited on the opening through dry etching, and by optimizing the protrusion ratio of the protrusions relative to the opening width, a vapor deposition mask capable of improving the pattern size of the vapor-deposited film was developed.

[0039] <Summary description of the vapor deposition mask 1 in this embodiment>

[0040] Figure 1 This is a cross-sectional view of the vapor deposition mask 1 in this embodiment. Figure 2 It is an enlarged plan view of the opening. Figure 3 It is an enlarged front view of the side wall surface revealed by cutting open the section. Figure 4A This is a SEM image showing the reference for measuring the protrusion size of the protrusion. Figure 4B This is a schematic diagram. Figure 5A This is an SEM image showing a magnified portion of the opening. Figure 5B This is a schematic diagram. Figure 7 is an SEM image of the sidewall of the opening.

[0041] The vapor deposition mask 1 is a stacked structure of thin film 2 and support substrate 3. Thin film 2 is a substrate having a first surface 2a and a second surface 2b opposite each other in the thickness direction. Although the thickness of thin film 2 is not limited, it is about 1µm to 300µm.

[0042] The outer periphery shape of the thin film 2 is preferably a rectangular or disk-shaped wafer. Although the diameter is not limited (the length of one side in the case of a rectangle), it is preferably about 100 mm to 500 mm.

[0043] Although not limited, the thin film 2 may be formed of a single layer or multiple layers. For example, the thin film 2 is preferably formed of a SiN layer or a stacked structure of SiN / SiO2 layers.

[0044] like Figure 1 As shown, multiple unit regions 4 are formed in the thin film 2. Between adjacent unit regions 4, there exists a region where no opening 8 is formed (called the "boundary region 5"). In the plan view, the multiple unit regions 4 are arranged with the boundary regions 5 in between. The area where the multiple unit regions 4 are grouped together is called the unit array region 6. Between the unit array region 6 and the end of the thin film 2 is the outer peripheral region 7.

[0045] like Figure 1 As shown, multiple openings 8 are formed in each unit region 4. The opening 8 extends from the first surface 2a of the film 2 to the second surface 2b.

[0046] like Figure 11 As shown, the first surface 2a is the surface opposite to the substrate 10 to be vapor-deposited, and the second surface 2b is the back surface opposite to the vapor deposition source 11.

[0047] like Figure 1 As shown, the opening width of opening 8 gradually narrows from the second surface 2b to the first surface 2a. Therefore, the sidewall surface 9 of opening 8 is inclined.

[0048] The planar pattern of the openings 8 (the shape observed from directly above the film 2 towards the first surface 2a) should not be limited. Examples include rectangles (including squares), polygons other than rectangles, circles, and ellipses. Furthermore, all openings 8 may have the same planar pattern, or some may differ. Additionally, the openings 8 may be arranged regularly, irregularly, or a mixture of regular and irregular arrangements.

[0049] Although the width of the boundary region 5 between each unit region 4 is not limited, when viewed from the first surface 2a, the width is approximately 1mm to 10mm.

[0050] like Figure 1 As shown, a support substrate 3 is provided on the second surface 2b side of the thin film 2.

[0051] The support substrate 3 is, for example, a silicon substrate. Although the thickness of the support substrate 3 is not limited, it is, for example, about 100µm to 1000µm.

[0052] like Figure 1 As shown, on the second surface 2b of the thin film 2, the support substrate 3 is disposed in the outer peripheral region 7 and the boundary region 5. Thus, the support substrate 3 is not disposed in the unit region 4, and the unit region 4 is open on both the first surface 2a and the second surface 2b. It should be noted that the support substrate 3 may also be disposed only in the outer peripheral region 7. The thin film 2 can maintain its extended state due to the support substrate 3, eliminating the need for mounting processing. Alternatively, an electrostatic chuck utilizing electrostatic force can be used to seal the vapor deposition mask 1 of this embodiment with the substrate 10 to be vapor-deposited. It should be noted that, as... Figure 1 As shown, the support substrates 3 provided in the boundary region 5 and the outer peripheral region 7 are all of the same height. However, for example, the height of the support substrate 3 provided in the boundary region 5 can be lower than that of the support substrate 3 provided in the outer peripheral region 7. However, by making the heights consistent, higher strength can be maintained.

[0053] <Detailed description of the opening 8 of the vapor deposition mask 1 in this embodiment>

[0054] like Figure 2 Plan view of opening 8, and Figure 3 The front view of the opening 8 shown by the cut-out opening 8 (both sides of the opening 8 are shown in cross-section) reveals that multiple protruding strips 20 extending from the first surface 2a towards the second surface 2b are formed on the side wall surface 9 of the opening 8. It should be noted that in this embodiment, the protruding strips 20 are sometimes referred to as "longitudinal stripes". The protruding strips 20 protrude from the side wall surface 9 toward the inside of the opening 8, therefore, as... Figure 2 and Figure 3 As shown, the side wall surface 9 becomes a stepped concave-convex structure.

[0055] The height (length) of the protrusion 20 from the first surface 2a side toward the second surface 2b side is the same as or shorter than the height (length) from the first surface 2a to the second surface 2b. That is, if the protrusion 20 is formed in the height region between the first surface 2a and the second surface 2b, this also includes cases where it is interrupted midway. However, the height of the protrusion 20 is preferably the same as the height (length) from the first surface 2a to the second surface 2b. Thus, the protrusion 20 is continuous in the height direction between the first surface 2a side and the second surface 2b side without interruption, and there is no unevenness or concavity in the height direction, or the difference in unevenness or concavity is small, thereby reducing the accumulation of vapor deposits.

[0056] Furthermore, the protrusion 20 can be formed in a straight line from the first surface 2a to the second surface 2b, or it can be curved, serpentine, or have a shape change midway (the direction of extension changes midway), and its shape is not particularly limited. However, the protrusion 20 is preferably straight. "Straight" does not mean a straight line in the strict sense, and some variations are allowed. Although not limited, for example, when the direction of extension changes within about 5 degrees relative to the direction perpendicular to the height direction, it can be considered as straight. By making the protrusion 20 straight, the area where the direction of extension changes can be eliminated or reduced, thereby reducing the accumulation of vapor deposits.

[0057] Figure 2 The opening 8 shown is roughly polygonal, but it could also be circular or elliptical. For example... Figure 2 As shown, the protrusions 20 are uniformly formed around the opening 8, but the formation density of the protrusions 20 can vary depending on the position of the sidewall surface 9. For example, the formation density of the protrusions 20 can change starting from the middle of the height direction of the sidewall surface 9.

[0058] [Methods for calculating prominent dimensions]

[0059] Figure 4A It is an SEM image with an opening of 8. Figure 4B This is a schematic diagram. The SEM (scanning electron microscope) image of opening 8 was obtained, for example, using a Hitachi High-Tech Regulus 8220.

[0060] in addition, Figure 5A yes Figure 4A A magnified image of the area surrounded by region A in the SEM image. Figure 5B This is a schematic diagram.

[0061] The following, such as Figure 4A , Figure 4B As shown, the case where opening 8 is a roughly polygonal shape will be explained.

[0062] like Figure 4A , Figure 4B As shown, draw straight reference lines L1 on each side of opening 8, connecting to the outer sides of the uneven steps of opening 8. At this time, as... Figure 5A , Figure 5B As shown, the baseline L1 is preferably drawn by connecting multiple points B. In addition, areas with extreme changes in the unevenness of the opening 8 and areas where the unevenness of the steps is difficult to distinguish in the SEM image are excluded, and the baseline L1 is drawn by connecting as many points B as possible.

[0063] Then, the baseline L1 is divided into three equal parts, for example, and the protrusion dimensions H1, H2, and H3 (hereinafter sometimes referred to as "protrusion dimensions H") of the protrusion 20 protruding from the central baseline L1 into the opening 8 are measured. It should be noted that the apex of each protrusion dimension H1, H2, and H3 is defined as the position where it protrudes most from the central baseline L1.

[0064] Then, the average protrusion dimension Ave H of the protrusion dimensions H1, H2, and H3 of each protrusion 20 is calculated.

[0065] It should be noted that if the shape of the opening 8 is circular or elliptical, then draw the baseline L1 in a curved shape along its shape. Then, divide the baseline into multiple parts, and use one of them to determine the protrusion dimension of the protrusion.

[0066] In the above description, the protrusion dimension H of the protrusion portion 20 was measured by dividing the reference line L1 into three equal parts; however, dividing it into three equal parts is just one example. Furthermore, the number of protrusion portions 20 measured from the reference line L1 is not limited, but can be approximately 2 to 50, preferably 30 or less, and more preferably 20 or less. Additionally, the number of measurements is 2 or more, preferably 5 or more. This improves the dimensional accuracy of the average protrusion dimension AveH of the protrusion portion 20.

[0067] Furthermore, in this embodiment, the measurement error of the average protrusion dimension AveH of the protrusion portion 20 can be tolerated to be ±10% or less, preferably ±5% or less.

[0068] [How to calculate opening width W1]

[0069] like Figure 1 or Figure 3 As shown, for example, the opening 8 gradually narrows from the second surface 2b toward the first surface 2a, and the opening width varies depending on the measurement location. In this embodiment, the first surface 2a side opposite to the vapor-deposited substrate 10 is defined as the opening width W1 of the opening 8.

[0070] It should be noted that the opening width W1 can be calculated from the SEM image obtained using the eCD-2 format from KLA-Tencor.

[0071] The opening width W1 can be calculated based on the reference line L1 used to determine the protrusion dimension H of the protrusion 20. However, when it is desired to calculate it based on the reference line L1, a larger difference between the area enclosed by the reference line L1 and the area of ​​the opening 8 means a larger separation between the reference line L1 and the opening 8, which can easily reduce the accuracy of the opening width W1 calculation. For example, when the area difference is 10% or more, preferably 5% or more, it is desirable to calculate the opening width W1 using the following method.

[0072] That is, the longest distance among the distances between each vertex 8a of the opening 8 in Figure 6 and the intersection point 8c is set as the opening width W1, where the intersection point 8c is the intersection of the straight line L2 from vertex 8a through the center O of ellipse 14 and the side 8b of the opening 8.

[0073] Figure 6 is a schematic diagram illustrating the calculation method for the opening width W1. Figure 6A In the diagram, opening 8 is approximately hexagonal. Therefore, there are 6 vertices 8a and 6 sides 8b of opening 8 appearing on side 2a of the first face. Side 8b is the regression line. The regression line can be obtained using the least squares method.

[0074] Next, draw the ellipse 14 circumscribed by each vertex 8a. Ellipse 14 also includes a circle. Then, find the center O of ellipse 14.

[0075] Draw a straight line L2 from each vertex 8a through the center O, and find the intersection point 8c where the straight line L2 intersects the side 8b of the opening 8. Then, calculate the distance between vertex 8a and intersection point 8c. Figure 6A In the middle, there are a total of 6 vertices 8a. Therefore, the distances are calculated for each of the 6 vertices 8a, and the longest distance is set as the opening width W1.

[0076] Figure 6B In the middle, opening 8 is a triangle. Figure 6C In the middle, the opening 8 is a pentagon. Figure 6D , Figure 6E A special shape representing polygonal deformation. Figures 6B to 6E In the diagram, the white circle represents vertex 8a, and the black circle represents intersection point 8c. For example... Figure 6A As described above, draw an ellipse 14 circumscribed to each vertex 8a and find the center O of the ellipse 14. Then, draw a straight line L2 from each vertex 8a through the center O, find the intersection point 8c of the straight line L2 and the side 8b of the opening 8, calculate the distance between vertex 8a and the intersection point 8c, and set the longest distance as the opening width W1.

[0077] It should be noted that when drawing ellipse 14, depending on the shape of the opening, it is sometimes difficult to draw an ellipse 14 that is circumscribed to all vertices 8a. In this case, draw an ellipse 14 that is circumscribed to as many vertices 8a as possible, and that is as close as possible to the curve of ellipse 14 at the vertices 8a that are not circumscribed. Alternatively, ellipse 14 may also have a portion that is drawn in a way that enters the inside of opening 8.

[0078] [Method for calculating the protrusion ratio of the protrusion 20]

[0079] As described above, the average protrusion size AveH of the protrusion 20 and the opening width W1 of the opening 8 are calculated, and the protrusion ratio (average protrusion size AveH / opening width W1) R is calculated.

[0080] The term "small protrusion ratio R" means that, assuming the average protrusion dimension AveH of the protruding part 20 is constant, the opening width W1 is large; or if the opening width W1 is constant, the average protrusion dimension AveH of the protruding part 20 is small. Conversely, the term "large protrusion ratio R" means that, assuming the average protrusion dimension AveH of the protruding part 20 is constant, the opening width W1 is small; or if the opening width W1 is constant, the average protrusion dimension AveH of the protruding part 20 is large. Thus, in this embodiment, by adjusting one or both of the average protrusion dimension AveH of the protruding part 20 and the opening width W1, the protrusion ratio R can be controlled within a specified range.

[0081] [Method for calculating the cone angle θ1 of opening 8]

[0082] In this embodiment, the cone angle θ1 of opening 8 is calculated as follows. That is, as... Figure 3 As shown, by connecting the end of the opening width W1 along the surface direction of the first surface 2a and the end of the opening width W2 along the surface direction of the second surface 2b with a straight line, the tilt angle between this straight line and the first surface 2a can be set as the cone angle θ1 of the opening 8. The cone angle θ1 is determined by measurement from the SEM image obtained using a Hitachi High-Tech Regulus 8220.

[0083] <Characteristics of the opening parameters in this embodiment>

[0084] The vapor deposition mask 1 in this embodiment is characterized by: (1) A protruding strip 20 extending from the first surface 2a to the second surface 2b is formed on the side wall surface 9 of the opening 8. (2) The protrusion ratio R of the protruding part 20 relative to the opening width W1 of the opening 8 is 0.001 or more and 0.018 or less.

[0085] The protrusion 20 shown in (1) above is produced by dry etching during the formation of the opening 8. That is, the protrusion 20 is a processing shape unique to dry etching, and is produced as a longitudinal stripe in the height direction (longitudinal direction) of the opening 8.

[0086] Protrusion 20 Figure 8 The accumulation of the vapor-deposited material 12 described herein is the cause of poor vapor deposition. The protrusion 20 is a processing shape unique to dry etching, but the size of the protrusion 20 has not been adjusted in the past.

[0087] Therefore, in this embodiment, the protrusion ratio R of the protrusion portion 20 is specified in such a way that the pattern width W3 of the vapor-deposited film 13 can be adjusted to more than 70% of the opening size (opening width W1).

[0088] The protrusion ratio R is characterized as described in (2) above. That is, in this embodiment, by adjusting the protrusion ratio R of the protrusion 20 relative to the opening width W1 of the opening to 0.001 or more and 0.018 or less, the pattern width W3 of the vapor-deposited film 13 can be appropriately and easily adjusted to 70% or more of the opening size (opening width W1).

[0089] Furthermore, in this embodiment, the protrusion ratio R is more preferably 0.014 or less. Therefore, the pattern width W3 of the vapor-deposited film 13 can be appropriately and easily adjusted to 80% or more, preferably 85% or more, and more preferably 90% or more of the opening size (opening width W1). Additionally, there is no limitation on the lower limit value of the protrusion ratio R, but it is set to 0.001 or more, 0.002 or more, 0.003 or more, or 0.004 or more, depending on the dry etching conditions.

[0090] Furthermore, by setting the protrusion ratio R to 0.001 or higher, it is possible to capture signals from the sidewall 9 of the opening 8. Figure 11 The impurities contained in the vapor deposition material (vapor deposition particles) 12 of the vapor deposition source 11 can be reduced, thus reducing the amount of impurities contained in the vapor deposition film 13. That is, particles that fly from the vapor deposition source 11 toward the substrate 10 to be vaporized contain impurities. Moreover, since the vapor deposition conditions are set such that the vapor deposition particles 12 attach in a direction orthogonal to the surface of the substrate 10 to be vaporized, impurities that deviate from these conditions are easily scattered obliquely in a direction orthogonal to the surface of the substrate 10 to be vaporized. Therefore, by making the protrusion ratio R non-zero, specifically set to 0.001 or higher, impurities are easily captured on the sidewall surface 9.

[0091] Furthermore, in this embodiment, the average protrusion size AveH of the protrusion 20 is preferably 150 nm or less, more preferably 145 nm or less, and even more preferably 143.5 nm or less. Therefore, the protrusion ratio R of the protrusion 20 relative to the opening width W1 of the opening 8 can be appropriately and easily adjusted to 0.001 or more and 0.018 or less.

[0092] Furthermore, in this embodiment, the maximum protrusion size of the protrusion 20 is preferably 200 nm or less, more preferably 185 nm or less, and even more preferably 181 nm or less. Therefore, there are no extremely large protrusions 20, effectively suppressing poor vapor deposition. Additionally, the protrusion ratio R of the protrusion can be appropriately and easily adjusted to 0.001 or more and 0.018 or less.

[0093] Furthermore, in this embodiment, the opening width W1 is preferably 10µm or less. There is no limitation on the lower limit; it can be set to 1µm or more. This ensures that the requirements for the vapor deposition mask 1 with the thin film 2 are met, especially for vapor deposition masks used in the RGB separation process of OLED microdisplays, where a further reduction in the opening width W1 is necessary.

[0094] In this embodiment, by reducing the opening width W1 of the opening 8 while adjusting the protrusion ratio R of the protrusion to 0.001 or more and 0.018 or less, it can be effectively used as the vapor deposition mask 1 in the manufacture of high-resolution OLED display devices.

[0095] like Figure 11 As shown, the vapor deposition material (vapor deposition particles) 12 from the vapor deposition source 11 passes through the opening 8 of the vapor deposition mask 1 and reaches the surface 10a of the substrate 10 to be vapor deposited, forming a vapor deposition film 13. When the pattern width W3 of the vapor deposition film 13 is measured to calculate the ratio to the opening width W1, if the pattern width ratio ((pattern width W3 / opening width W1) × 100 (%)) is 70% or more, it is used as the protrusion ratio R, while a protrusion ratio R of less than 70% is used as a comparative example.

[0096] Furthermore, in this embodiment, the opening width W1 of the opening 8 gradually narrows from the second surface 2b side toward the first surface 2a side, but it is not limited to this; it may also gradually widen from the second surface 2b side toward the first surface 2a side. Although the cone angle is not limited, the cone angle θ1 is preferably 60° or more and 120° or less, more preferably 70° or more and 110° or less, and even more preferably 80° or more and 105° or less.

[0097] The sidewall 9 of the opening 8 is preferably a conical surface extending from the second surface 2b towards the first surface 2a, formed by creating an inverted conical surface extending from the vapor deposition source 11 side, i.e., from the second surface 2b towards the first surface 2a (see reference). Figure 11 This allows the vaporized particles 12 to easily pass from the vaporization source 11 toward the substrate 10 to be vaporized, thus forming a vaporized film 13 with excellent pattern size.

[0098] <Regarding the manufacturing method of the vapor deposition mask 1 in this embodiment>

[0099] Figure 9 is a process diagram illustrating the manufacturing method of the vapor deposition mask 1 according to this embodiment. Here, the vapor deposition mask 1 shown in Figure 9 and Figure 10 (described later) only shows the vicinity of one unit region 4, but in reality, it is formed simultaneously. Figure 1 The multiple unit regions shown are 4.

[0100] exist Figure 9A In, for example, a support substrate 21 made of Si is prepared, in Figure 9B In this process, a thin film 2 is formed on the surface of the support substrate 21. For example, the thin film 2 is configured as a stacked structure of SiO2 layer 22 and SiN layer 23.

[0101] Although the diameter of the film 2 is not limited, in this embodiment it can be up to about 50 mm.

[0102] exist Figure 9C In this process, a protective material 24 is formed on the entire surface of the thin film 2. Additionally, a mask layer 25 is formed on the back side of the supporting substrate 21. The mask layer 25 is a resist pattern. Figure 9C As shown, the mask layer 25 is not formed on the part of the thin film 2 opposite to the unit region 4.

[0103] Then, in Figure 9D In the process shown, the support substrate 21 not covered by the mask layer 25 is removed by dry etching. As a result, the support substrate 3 is formed on the second surface 2b of the thin film 2, except for the location of the cell region 4. Then, the mask layer 25 is removed.

[0104] Next, in Figure 9E In the process shown, a resist layer is coated from the support substrate 3 to the second surface 2b of the unit region 4, and a mask layer 26 having an opening pattern 26a is formed on the resist layer. The opening pattern 26a is a pattern used to form an opening 8 in the thin film 2, and the thin film 2 exposed from the opening pattern 26a is removed by dry etching. Thus, an opening 8 can be formed in the thin film 2.

[0105] exist Figure 9F In the process, the mask layer 26 and the protective material 24 are removed. Thus, the vapor deposition mask 1 is completed, which has: a thin film 2 having multiple openings 8 in the unit region 4, and a support substrate 3 formed on the second surface 2b side of the thin film 2. In the manufacturing method shown in FIG9, the cone angle θ1 of the openings 8 can be formed from a cone surface of 90° or less.

[0106] The manufacturing method of the vapor deposition mask 1 shown in Figure 10 will be described. Figure 10 shows... Figure 10A and Figure 10B process and Figure 9A and Figure 9B same.

[0107] exist Figure 10CIn this case, mask layers 27 and 28 are formed on both the first surface 2a of the thin film 2 and the back surface of the support substrate 21. It is preferable that the mask layers 27 and 28 are both formed of a resist.

[0108] As Figure 10C shown, the mask layer 28 formed on the back surface of the support substrate 21 is not formed in the cell region 4 of the thin film 2. In addition, a plurality of opening patterns 27a are formed in the mask layer 27 formed on the first surface 2a of the thin film 2. Through the opening patterns 27a, a plurality of openings 8 can be formed in the thin film 2.

[0109] In Figure 10D this case, the thin film 2 exposed from the opening patterns 27a of the mask layer 27 is removed by dry etching. Thus, a plurality of openings 8 can be formed in the thin film 2.

[0110] Next, the support substrate 21 not covered by the mask layer 28 is removed. Thus, the cell region 4 of the thin film 2 is also open on the second surface 2b. Then, the mask layers 27 and 28 are removed.

[0111] Thus, as Figure 10E shown, the evaporation mask 1 is completed, which has: a thin film 2 having a plurality of openings 8 in the cell region 4, and a support substrate 3 formed on the second surface 2b side of the thin film 2. In the manufacturing method shown in FIG. 10, the taper angle θ1 of the opening 8 can be formed by an inverted conical surface of 90° or more.

[0112] As Figure 9E and Figure 10D shown, for example, the conditions of the dry etching used when forming the openings 8 in the thin film 2 are adjusted as follows.

[0113] As the etching conditions, adjustment can be made by various gas flows, chamber pressures, and the power of the plasma generation source, etc.

[0114] As an example, as the etching gas, CF4 gas and O2 gas are used. The CF4 gas is set to 0.1 to 100 sccm, and the O2 gas is set to 1 to 200 sccm. In addition, the Platen LF is set to 500 to 3000 W, the Coil RF is set to 500 to 4000 W, the chamber pressure is set to 1 to 10 Pa, and the etching time is set to about a few minutes to adjust various conditions. Regarding the gas flows of the CF4 gas and the O2 gas, it is preferable to adjust the flow rate of the CF4 gas < the flow rate of the O2 gas.

[0115] Thus, the protruding size of the plurality of vertical stripes (protruding portions) can be reduced (which can also be referred to as the groove depth between the vertical stripes). Specifically, the protruding ratio R of the protruding portion 20 with respect to the opening width W1 of the opening 8 can be appropriately adjusted to be 0.001 or more and 0.018 or less.

[0116] It should be noted that fluorine compounds can be selected from one or more of CF4, SF6, NF3, BF3, PF5, and F2. In addition, rare gases can be selected from one or more of helium or argon, but they can also be omitted.

[0117] In addition, the protruding size of the protrusion 20 can be reduced by laser hydrogen annealing and other processes.

[0118] <Method for manufacturing electronic devices according to this embodiment>

[0119] In this embodiment, such as Figure 11 As shown, a vapor deposition mask 1 is positioned between the substrate 10 to be vapor-deposited and the vapor deposition source 11. At this time, the first surface 2a of the thin film 2 of the vapor deposition mask 1 faces the substrate 10 to be vapor-deposited, and the second surface 2b of the thin film 2 faces the vapor deposition source 11. A plurality of openings 8 are formed in the thin film 2, for example, the opening width is narrower on the first surface than on the second surface.

[0120] The vapor deposition mask 1 is placed on the support (not shown) of the vapor deposition apparatus. At this time, an electrostatic chuck can be used to fix the vapor deposition mask 1 and the substrate 10 to be vapor-deposited. Figure 11 In the process, the thin film 2 is separated from the substrate 10 to be deposited, but they can still be in contact. The vapor deposition mask 1 and the substrate 10 to be deposited are rotated about the center of the support axis.

[0121] Evaporation material (evaporation particles) 12 from evaporation source 11 reaches the surface 10a of the substrate 10 to be evaporated through the opening 8 of evaporation mask 1, forming an evaporation film 13.

[0122] In this embodiment, examples of electronic devices include OLED microdisplay panels, liquid crystal panels, and solar cells, and the method for manufacturing OLED microdisplay panels as organic electronic devices is particularly applicable.

[0123] By using the vapor deposition mask 1 of this embodiment, it can be ensured that the pattern width W3 of the vapor deposition film 13 is 70% or more, preferably 75% or more, and more preferably 80% or more, relative to the opening width W1. In this way, a vapor deposition film 13 with excellent pattern size can be formed.

[0124] <Regarding the effects of using the vapor deposition mask 1 of this embodiment>

[0125] In this embodiment, by specifying the protrusion ratio of the protrusions 20 in the openings 8 of the vapor deposition mask 1, a high pattern size of the vapor deposition film 13 can be obtained. Furthermore, since the amount of vapor deposition material accumulated can be reduced, the cleaning frequency of the vapor deposition mask 1 can be reduced, making quality management of the vapor deposition mask 1 easier. Additionally, the occurrence of clogging in the openings 8 can be reduced, enabling a longer lifespan for the vapor deposition mask 1.

[0126] It should be noted that although the implementation methods and variations have been described, the above implementation methods and variations may be combined in whole or in part as other implementation methods.

[0127] Furthermore, the present invention is not limited to the above-described embodiments and modifications, and various changes, substitutions, and modifications can be made without departing from the spirit of the technical concept. In addition, if the technical concept can be implemented in other ways based on technological advancements or other derived technologies, this method can also be used. Therefore, the claims cover all embodiments that can be included within the scope of the technical concept.

[0128] to and Figure 1 The embodiments of the vapor deposition mask 1 with different layer configurations will be described.

[0129] For example, such as Figure 12 As shown, the film 31, such as SiN or SiO2, can also be formed on the surface of a frame-shaped silicon substrate 30, and a plurality of openings 8 can be formed in the film 31 in the central region after the silicon substrate 30 has been removed. The film can be formed by CVD, but from the viewpoint of easy stress control, SiN is preferred.

[0130] exist Figures 13 to 15 In other embodiments shown, an SOI substrate 39 is used, but in Figure 13 In the process, a SiN layer 45 is formed on the back side of the SOI substrate 39 (the side of the support substrate 44, the side opposite to the evaporation source 11); Figure 14 In the process, a SiN layer 45 is formed on the surface side of the SOI substrate 39 (the side of semiconductor layer 42, the side opposite to the substrate 10 to be deposited); Figure 15 In this configuration, SiN layers 45 are formed on both the back side and the surface side of the SOI substrate 39. In the configuration where the SiN layer 45 is formed on the surface side (semiconductor layer 42 side) of the SOI substrate 39, an opening 8 is formed continuously with the semiconductor layer 42.

[0131] By setting a SiN layer 45, stress control of the vapor deposition mask can be easily achieved, and strain can be suppressed.

[0132] Furthermore, the SiN layer 45 formed on the surface side of the SOI substrate 39 is preferably thinner than the SiN layer 45 formed on the back side of the SOI substrate 39. Although not limited, the film thickness of the SiN layer 45 formed on the surface side of the SOI substrate 39 is about 0.05 μm to 0.5 μm, and the film thickness of the SiN layer 45 formed on the back side of the SOI substrate 39 is about 0.05 μm to 3 μm. Since the semiconductor layer 42 is thinner than the support substrate 44, and multiple openings 8 are formed in the semiconductor layer 42, the SiN layer 45 formed on the surface side of the SOI substrate 39 is formed thinner than the SiN layer 45 formed on the back side of the SOI substrate 39 in order to control stress evenly on both the surface and back sides.

[0133] It should be noted that the opening 8 can be formed using the Bosch process for the SOI substrate 39, and the opening 8 can be formed using dry etching for the SiN layer 45.

[0134] in addition, Figure 1 At least one of the supporting substrate 3 and the thin film 2 shown can be a polycrystalline silicon structure. Therefore, since polycrystalline silicon does not have a defined cleavage plane, it is less prone to fracture in the cleavage direction compared to using monocrystalline silicon which has cleavage planes.

[0135] Furthermore, fabricating large substrates from monocrystalline silicon is technically difficult, but by making the evaporation mask 1 a polycrystalline silicon structure, it is easy to form silicon substrates larger than monocrystalline silicon substrates. Additionally, by making the planar shape of the evaporation mask 1 polygonal (e.g., quadrilateral), compared to making the evaporation mask 1 circular, chamfering efficiency can be improved, and the number of facets can also be increased. It should be noted that the large-size silicon substrate is preferably 500mm × 500mm or larger.

[0136] Example

[0137] The effects of the present invention will be described below through embodiments and comparative examples. It should be noted that the present invention is not limited to any of the following embodiments.

[0138] <Sample fabrication of vapor deposition masks>

[0139] Samples of multiple vapor deposition masks were fabricated using the manufacturing method shown in Figure 9 or Figure 10. In this case, the thin film was configured as a SiO2 / SiN stacked structure.

[0140] In the experiment, various changes were made to the dry etching conditions when forming the opening of the thin film, and multiple samples with different protrusion sizes of the protrusions were made (Experimental Examples 1-30).

[0141] <SEM image of the protruding part>

[0142] Figure 7A It is an SEM image of the sidewall of the opening. Figure 7B This is a schematic diagram. (For example...) Figure 7A and Figure 7B As shown, multiple longitudinal stripes (protrusions) extending along the height direction can be confirmed on the sidewall surface based on the SEM image.

[0143] (Regarding the vapor deposition conditions in the experiment)

[0144] Next, using Experimental Examples 1-6 shown in Table 1 (with an opening width W1 of 3µm), the vapor deposition material was vacuum deposited onto the substrate. Then, the pattern width W3 of the vapor deposition film was measured using a laser microscope (model: VKX-210 (manufactured by Keyence)) to determine the vapor deposition pattern width ratio (converted to 100%) relative to the opening width W1 of the vapor deposition mask.

[0145] At this point, regarding the vapor deposition amount (time) applied to the experiment, the vapor deposition conditions after Experiment 7 were determined to be the case where one or more samples in Experiment Examples 1 to 6 had a vapor deposition pattern width ratio of less than 70%.

[0146] <Judgment Criteria>

[0147] Experimental examples with a pattern width ratio of less than 70% are marked as ×, experimental examples with a pattern width ratio of 70-85% are marked as ○, and experimental examples with a pattern width ratio of more than 85% are marked as ◎.

[0148] The experimental results are shown in Table 1 below.

[0149] [Table 1]

[0150] As shown in Table 1, by setting the protrusion ratio (calculated from the average protrusion size / opening width of the opening) to below 0.018, the pattern width ratio can be above 70% (judged as ○ or ◎), and a vapor-deposited film can be formed with a stable pattern width size.

[0151] Furthermore, it is known that by setting the protrusion ratio (calculated from the average protrusion size / opening width of the opening) to below 0.014, the pattern width ratio can exceed 85% (judged as ◎), and the pattern width accuracy of the vapor-deposited film can be formed more stably.

[0152] Furthermore, the lower the threshold for the salience ratio, the better; it should be set to 0.001 or higher. Additionally, based on experimental examples, the salience ratio can be set to 0.004 or higher.

[0153] In addition, the average protrusion size of the protrusion portion is set to 150 nm or less, more preferably 145 nm or less, and even more preferably 143.5 nm or less.

[0154] In addition, the maximum protrusion size of the protrusion is set to 200 nm or less, more preferably 185 nm or less, and even more preferably 181 nm or less.

[0155] Furthermore, the opening width is preferably 10µm or less. Additionally, the lower limit of the opening width is set to 1µm, but according to experimental examples, it can also be 3µm or more.

[0156] It should be noted that the “cone angle” shown in Table 1 is a representative value, confirming that all experimental cases are within ±3° of each representative value.

[0157] This application is based on Japanese Special Petition 2024-097401, filed on June 17, 2024. Its entire contents are contained herein.

Claims

1. A vapor deposition mask having a first surface and a second surface opposite to the first surface, and having a plurality of openings penetrating between the first surface and the second surface, characterized in that, A protruding strip extending from the first surface to the second surface is formed on the sidewall of the opening. The protrusion ratio of the protrusion relative to the opening width of the opening is 0.001 to 0.

018.

2. The vapor deposition mask according to claim 1, characterized in that, The prominence ratio is below 0.

014.

3. The vapor deposition mask according to claim 1, characterized in that, When the side of the substrate to be vapor-deposited is designated as the first surface and the side of the vapor deposition source is designated as the second surface... The opening width is defined by the opening width of the first face side.

4. The vapor deposition mask according to claim 1, characterized in that, The average protrusion size of the protrusion is less than 150 nm.

5. The vapor deposition mask according to claim 1, characterized in that, The maximum protrusion size of the protrusion is less than 200 nm.

6. The vapor deposition mask according to claim 1, characterized in that, The opening width is less than 10µm.

7. The vapor deposition mask according to claim 1, characterized in that, The vapor deposition mask is a structure in which a thin film with the opening is supported by a supporting substrate, and the thin film is composed of a single layer of silicon nitride film or a stacked structure of silicon nitride film and silicon oxide film.

8. The vapor deposition mask according to claim 1, characterized in that, The vapor deposition mask is made of an SOI substrate, and a SiN layer is formed on the surface side where the opening is formed, or on the back side, or on both the surface side and the back side.

9. The vapor deposition mask according to claim 1, characterized in that, The vapor deposition mask is configured such that a thin film with the opening is supported by a support substrate. At least one of the thin film or the supporting substrate is a polycrystalline silicon structure.

10. A method for manufacturing an electronic device, characterized in that, The vapor deposition mask of claim 1 is configured between the substrate to be vaporized and the vapor deposition source, such that the first surface faces the substrate to be vaporized and the second surface faces the vapor deposition source. The vapor deposition material is deposited onto the surface of the substrate through the opening.

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