CN113416923A

CN113416923A - Metal shade

Info

Publication number: CN113416923A
Application number: CN202110557109.5A
Authority: CN
Inventors: 侯冠廷; 李清锋
Original assignee: Darwin Precisions Corp
Current assignee: Darwin Precisions Corp
Priority date: 2021-01-13
Filing date: 2021-05-21
Publication date: 2021-09-21
Anticipated expiration: 2041-05-21
Also published as: CN113416923B; TW202227651A; TWI805984B

Abstract

The metal mask includes at least one working area and a peripheral blank area. The working block comprises a peripheral part and a central part. The peripheral part is provided with a plurality of first openings, the central part is provided with a plurality of second openings, the peripheral part surrounds and is connected with the central part, and the thickness of the peripheral part is larger than that of the central part. The peripheral blank block surrounds and is connected with the working block.

Description

Metal shade

Technical Field

The present invention relates to a mask, and more particularly, to a metal mask suitable for use in fabricating a patterned film.

Background

Some Organic Light-Emitting Diode Display panels (OLED Display panels) are manufactured by an evaporation process, wherein the evaporation process usually uses a metal mask to fabricate a plurality of Organic Light-Emitting Diode devices, and the metal mask can be formed by photolithography and wet etching of a metal plate. The metal mask has a plurality of openings, which are usually formed by wet etching.

Due to the loading effect of the wet etching, the etching rate (etching rate) is not the same at all positions of the metal plate, so that the sizes of the openings are not uniform. For example, in the same metal mask, the openings at the edges have a significantly larger size, but the openings at the center have a significantly smaller size. These openings with different sizes are not favorable for manufacturing the oled display panel with high resolution, so that the resolution of most of the oled display panels at present is difficult to further increase.

Disclosure of Invention

At least one embodiment of the present invention provides a metal mask suitable for fabricating a patterned film.

The metal mask provided by at least one embodiment of the invention comprises at least one working area and a peripheral blank area. The working block comprises a peripheral part and a central part. The peripheral part is provided with a plurality of first openings, the central part is provided with a plurality of second openings, the peripheral part surrounds and is connected with the central part, and the thickness of the peripheral part is larger than that of the central part. The peripheral blank block surrounds and is connected with the working block.

In at least one embodiment of the present invention, the metal mask has a first surface and a second surface opposite to the first surface, and the first openings and the second openings extend to the first surface and the second surface. Each first opening has a first annular rib and a first sidewall. The first annular bead is located between the first surface and the second surface. The first sidewall is connected between the first surface and the first annular ribs, wherein the first annular ribs are substantially all located on the reference plane. A first included angle is formed between the first side wall and the reference plane, wherein the first included angle is smaller than 90 degrees. Each second opening has a second annular rib and a second sidewall. The second annular rib is located between the first surface and the second surface, and the second sidewall is connected between the first surface and the second annular rib, wherein the second annular ribs are all located substantially on the reference plane. A second included angle is formed between the second side wall and the reference plane, wherein the second included angle is smaller than the first included angle.

In at least one embodiment of the present invention, the change of the first included angles in the peripheral portion decreases from the peripheral blank block toward the central portion.

In at least one embodiment of the present invention, the metal mask has a first surface and a second surface opposite to the first surface, and the first openings and the second openings extend to the first surface and the second surface. The first surface is provided with a plurality of point planes, and the point planes are distributed on the periphery and are not distributed in the peripheral blank area.

In at least one embodiment of the present invention, the first surface further has a plurality of terminals, and the terminals are distributed only in the central portion and not distributed in the peripheral portion and the peripheral blank area.

In at least one embodiment of the present invention, at least one end point is located between four adjacent second openings.

In at least one embodiment of the present invention, at least one point-shaped plane is located between four adjacent first openings.

In at least one embodiment of the present invention, the first openings and the second openings are arranged in an array.

Based on the above, the metal mask according to at least one embodiment of the present invention is suitable for fabricating a patterned film layer, and more particularly suitable for fabricating a plurality of light emitting layers of an oled display panel, by using the first openings and the second openings.

The invention is described in detail below with reference to the drawings and specific examples, but the invention is not limited thereto.

Drawings

Fig. 1A is a schematic bottom view of a metal mask according to at least one embodiment of the invention.

Fig. 1B is an enlarged schematic view of the region 1B in fig. 1A.

Fig. 1C is an enlarged schematic view of the region 1C in fig. 1A.

FIG. 2 is a schematic cross-sectional view taken along line 2-2 in FIG. 1B.

Wherein, the reference numbers:

1B, 1C: region(s)

100: metal shade

101: first surface

102: second surface

101 p: endpoint

101 s: point-like plane

110: work block

111: peripheral part

112: center part

120: peripheral blank block

A1: first included angle

A2: second included angle

F1: the first annular bead

F2: second annular bead

H1: first opening

H2: second opening

RF 1: reference plane

S1: first side wall

S2: second side wall

T1, T2: thickness of

Detailed Description

In the following description, the dimensions (e.g., length, width, thickness, and depth) of elements (e.g., layers, films, substrates, regions, etc.) in the figures are exaggerated in various proportions for clarity of presentation. Accordingly, the following description and illustrations of the embodiments are not limited to the sizes and shapes of elements shown in the drawings, but are intended to cover deviations in sizes, shapes and both that result from actual manufacturing processes and/or tolerances. For example, the planar surfaces shown in the figures may have rough and/or non-linear features, while the acute angles shown in the figures may be rounded. Accordingly, the components shown in the drawings are for illustrative purposes only, and are not intended to accurately depict the actual shape of the components nor limit the scope of the claims.

Furthermore, the terms "about", "approximately" or "substantially" as used herein encompass not only the explicitly recited values and ranges of values, but also the allowable range of deviation as understood by those of ordinary skill in the art, wherein the range of deviation can be determined by the error in measurement, for example, due to limitations of both the measurement system and the process conditions. Furthermore, "about" can mean within one or more standard deviations of the above-described values, e.g., within ± 30%, 20%, 10%, or 5%. The terms "about," "approximately," or "substantially," as used herein, may be selected with an acceptable range of deviation or standard deviation based on optical, etching, mechanical, or other properties, and not all such properties may be applied with one standard deviation alone.

Fig. 1A is a schematic bottom view of a metal mask according to at least one embodiment of the invention. Referring to fig. 1A, the metal mask 100 includes at least one working block 110. In the embodiment shown in fig. 1A, the metal mask 100 may include a plurality of working areas 110, and in other embodiments, the number of the working areas 110 included in the metal mask 100 may be only one. Therefore, although the metal mask 100 of fig. 1A includes a plurality of working areas 110, fig. 1A does not limit the number of working areas 110 included in the metal mask 100.

The work blocks 110 may be arranged regularly. Taking fig. 1A as an example, the work blocks 110 may be arranged in a row. In other embodiments, the work blocks 110 may be arranged in an array. Therefore, fig. 1A does not limit the arrangement of the work blocks 110. In addition, the metal mask 100 further includes a peripheral blank area 120, wherein the peripheral blank area 120 surrounds and is located on the work areas 110.

Fig. 1B is an enlarged schematic view of the region 1B in fig. 1A. Referring to fig. 1B, each of the work blocks 110 includes a peripheral portion 111 and a central portion 112, wherein the peripheral portion 111 surrounds and connects the central portion 112. The peripheral portion 111 has a plurality of first openings H1, and the central portion 112 has a plurality of second openings H2, wherein the first openings H1 and the second openings H2 may be arranged in an array, and the first openings H1 and the second openings H2 may have substantially the same or similar sizes. For example, the maximum difference between the pore diameters of the first opening H1 and the second opening H2 may be less than or equal to 0.3 μm. In addition, the peripheral blank area 120 may not have any opening to maintain or improve the structural strength of the metal mask 100.

The metal mask 100 is suitable for use in fabricating a patterned film layer, and may be applied in semiconductor manufacturing or display panel manufacturing. For example, the metal mask 100 can be applied to a method for manufacturing an organic light emitting diode display panel, wherein the metal mask 100 is suitable for a process for manufacturing a plurality of light emitting layers, which may include Physical Vapor Deposition (PVD) such as evaporation or sputtering. In the process of performing evaporation or sputtering to form the light emitting layer on the substrate (e.g., a glass plate), the metal mask 100 can shield the plating material from the plating source and deposit the plating material on the surface of the substrate exposed by the first opening H1 and the second opening H2. Thus, the light emitting layers can be formed on the surfaces of the plated substrates exposed by the first opening H1 and the second opening H2, respectively.

The light emitting layer can be used as a sub-pixel (sub-pixel), and thus the size of each of the first opening H1 and the second opening H2 can be equal to the size of one sub-pixel. In addition, the size of each work area 110 may correspond to the size of one display panel. For example, the size of the work block 110 may correspond to the size of a display panel in a smart phone or tablet computer. The working blocks 110 may be manufactured in different sizes according to different sizes of various display panels (e.g., organic light emitting diode display panels).

Since the sizes of the first opening H1 and the second opening H2 can be substantially the same or similar, for example, the maximum difference between the diameters of the first opening H1 and the second opening H2 can be less than or equal to 0.3 μm, the light emitting layers formed in the first opening H1 and the second opening H2 have substantially the same or similar sizes. Compared with the conventional metal mask, the metal mask 100 of at least one embodiment of the present invention can manufacture a plurality of light emitting layers with the same or similar size, which is beneficial for manufacturing a high-resolution display panel, thereby improving the resolution of the display panel.

In addition, the metal mask 100 may have a plurality of point planes 101s and a plurality of end points 101p, wherein the point planes 101s and the end points 101p are located on the same side of the metal mask 100. For example, the point plane 101s and the end point 101p are located on the lower surface of the metal mask 100. The dot-shaped planes 101s are distributed in the peripheral portion 111 but not distributed in the peripheral blank region 120, wherein the dot-shaped planes 101s may not be distributed in the central portion 112, as shown in fig. 1B. It should be noted that fig. 1B is not intended to limit the distribution of the point-shaped plane 101s and the end point 101 p.

At least one dot plane 101s is located between four adjacent ones of these first openings H1. Taking fig. 1B as an example, among the plurality of dot planes 101s adjacent to the peripheral blank block 120, each dot plane 101s is located between four adjacent first openings H1. In other words, the four adjacent first openings H1 surround one dot plane 101 s. Further, the four first openings H1 adjacent to and surrounding the dot plane 101s may be arranged in a2 × 2 matrix.

Fig. 1C is an enlarged schematic view of the region 1C in fig. 1A. Referring to fig. 1C, in the present embodiment, at least one end point 101p is located between four adjacent second openings H2. Taking fig. 1C as an example, each end point 101p is located between four adjacent second openings H2. Referring to fig. 1B and 1C, as can be seen from fig. 1B and 1C, the terminals 101p are only distributed in the central portion 112, but not distributed in the peripheral portion 111 and the peripheral blank area 120.

FIG. 2 is a schematic cross-sectional view taken along line 2-2 in FIG. 1B. Referring to fig. 1B and fig. 2, the metal mask 100 has a first surface 101 and a second surface 102, wherein the first surface 101 and the second surface 102 are opposite to each other. Taking fig. 2 as an example, the first surface 101 and the second surface 102 may be a lower surface and an upper surface of the metal mask 100, respectively. The first openings H1 and the second openings H2 extend to the first surface 101 and the second surface 102. In other words, the first opening H1 and the second opening H2 are both formed through the metal mask 100, so the first surface 101 and the second surface 102 both expose the first openings H1 and the second openings H2.

As can be seen from fig. 2, the thickness of the metal mask 100 is not uniform, wherein the thickness T1 of the peripheral portion 111 is significantly greater than the thickness T2 of the central portion 112. In addition, in the present embodiment, the thickness variation of the peripheral portion 111 in the same work block 110 may be increased from the central portion 112 toward the peripheral blank block 120, as shown in fig. 2, wherein the thickness T1 shown in fig. 2 may be the minimum thickness of the peripheral portion 111, rather than the maximum thickness of the peripheral portion 111.

Specifically, fig. 1A is a schematic bottom view of the metal mask 100, so fig. 1B and 1C are schematic partial bottom views of the metal mask 100. That is, fig. 1B is drawn by viewing the metal mask 100 from the first surface 101 in fig. 2. As can be seen from fig. 1B and fig. 2, the first surface 101 has the dot planes 101s and the end points 101p, so that the dot planes 101s and the end points 101p are both located on the lower surface of the metal mask 100 in fig. 2, i.e., the first surface 101.

Each of the first openings H1 has a first annular rib F1 and a first sidewall S1, wherein the first annular rib F1 is located between the first surface 101 and the second surface 102. The first side wall S1 is connected between the first surface 101 and the first annular rib F1, and the first side wall S1 is annular in shape, wherein the first annular rib F1 may extend along an edge of the first side wall S1.

As seen in fig. 2, the apertures of the first openings H1 are not uniform, wherein the minimum aperture of the first openings H1 is substantially equal to the inner diameter of the first annular ridge F1. The first annular fins F1 are substantially all located on the reference plane RF1, wherein the reference plane RF1 is a virtual plane. In other words, the first annular ridges F1 are substantially coplanar (coplanar). In addition, the first side wall S1 and the reference plane RF1 form a first included angle a1 smaller than 90 degrees, as shown in fig. 2.

The second opening H2 has a structure and shape similar to those of the first opening H1. Specifically, each of the second openings H2 has a second annular rib F2 and a second side wall S2, wherein the second annular rib F2 is located between the first surface 101 and the second surface 102. The second side wall S2 is connected between the first surface 101 and the second annular rib F2, and the second side wall S2 is also annular in shape, wherein the second annular rib F2 may extend along an edge of the second side wall S2.

From the perspective of fig. 2, the bore diameter of each second opening H2 is also non-uniform, wherein the minimum bore diameter of the second opening H2 is substantially equal to the inner diameter of the second annular ridge F2. In addition, the second annular ribs F2 are substantially located on the reference plane RF1, so the first annular ribs F1 and the second annular ribs F2 are substantially located on the same reference plane RF 1. In other words, the first annular ribs F1 are substantially coplanar with the second annular ribs F2. In addition, the second side wall S2 forms a second included angle A2 with the reference plane RF1, which is smaller than the first included angle A1.

The first openings H1 and the second openings H2 can be formed by photolithography and wet etching, so that the metal mask 100 can be a metal plate after photolithography and wet etching. Therefore, before wet etching, the two opposite surfaces of the metal plate are covered by two mask patterns, wherein the mask patterns may be photoresist patterns after development, and cover the peripheral blank region 120 and all the working regions 110, exposing only the surface of the metal plate on which the first openings H1 and the second openings H2 are to be formed. In other words, the shielding patterns each have a plurality of through holes corresponding to the first opening H1 and the second opening H2, wherein the through holes partially expose the metal plate surface (corresponding to the first surface 101 and the second surface 102).

Due to the loading effect of the wet etching, the etching rate (etching rate) of the area near the peripheral blank block 120 is significantly faster than that of the area far from the peripheral blank block 120. Therefore, the through holes of each shielding pattern are not designed to have the same size, wherein the through hole (corresponding to the first opening H1) near the peripheral blank block 120 has a smaller size, and the through hole (corresponding to the second opening H2) far from the peripheral blank block 120 has a larger size, so that the sizes of the first opening H1 and the second opening H2 affected by the loading effect can be the same or similar, thereby reducing the difference between the apertures of the first opening H1 and the second opening H2.

In addition, since the sizes of the through holes of the shielding patterns are different, and the loading effect of wet etching is added, the point planes 101s are distributed in the peripheral portion 111 but not distributed in the central portion 112, and the terminals 101p are distributed only in the central portion 112 but not distributed in the peripheral portion 111. Next, the changes of the first included angles a1 in the peripheral portion 111 are decreased from the peripheral blank area 120 to the central portion 112, as shown in fig. 2.

In summary, the metal mask of at least one embodiment of the invention is suitable for fabricating a patterned film layer, for example, a plurality of light emitting layers of an oled display panel. Moreover, the metal mask of at least one embodiment of the invention can manufacture a plurality of light emitting layers with the same or similar sizes, which is beneficial to manufacturing a display panel with high resolution so as to improve the resolution of the display panel.

Although the present invention has been described with reference to particular embodiments, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

The present invention is capable of other embodiments, and various changes and modifications may be made by one skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A metal mask, comprising:

at least one work block, comprising:

a peripheral portion having a plurality of first openings;

a central part with a plurality of second openings, wherein the peripheral part surrounds and is connected with the central part, and the thickness of the peripheral part is larger than that of the central part; and

a peripheral blank block surrounding and connected to the at least one working block.

2. The metal mask as claimed in claim 1, wherein the metal mask has a first surface and a second surface opposite to the first surface, and the first opening and the second opening both extend to the first surface and the second surface, each first opening having:

a first annular rib located between the first surface and the second surface; and

a first sidewall connected between the first surface and the first annular rib, wherein the first annular rib is substantially located on a reference plane, and a first included angle is formed between the first sidewall and the reference plane, wherein the first included angle is smaller than 90 degrees;

each of the second openings has:

a second annular rib located between the first surface and the second surface; and

and a second side wall connected between the first surface and the second annular rib, wherein the second annular rib is substantially located on the reference plane, and a second included angle is formed between the second side wall and the reference plane, wherein the second included angle is smaller than the first included angle.

3. The metal mask of claim 2, wherein the variation of the first included angle in the peripheral portion decreases from the peripheral blank area toward the central portion.

4. The metal mask as claimed in claim 1, wherein the metal mask has a first surface and a second surface opposite to the first surface, the first opening and the second opening both extend to the first surface and the second surface, the first surface has a plurality of point-shaped planes, and the point-shaped planes are distributed on the periphery and not distributed on the peripheral blank region.

5. The metal mask as in claim 4, wherein the first surface further has a plurality of terminals, and the terminals are distributed only in the central portion and not distributed in the peripheral portion and the peripheral blank area.

6. The metal mask of claim 5, wherein at least one of the end points is located between four adjacent second openings.

7. The metal mask of claim 4, wherein at least one of said point planes is located between four adjacent ones of said first openings.

8. The metal mask of claim 1, wherein the first openings and the second openings are arranged in an array.