Improved mask plate

Abstract

The utility model discloses an improved mask plate, the mask plate is used for performing evaporation operation on a substrate, the bottom of the substrate is provided with a supporting salient point, the supporting salient point is of a hemispherical structure, and the supporting salient point is used for supporting the mask plate when the mask plate is aligned with the substrate. The alignment limiting holes corresponding to the supporting convex points in position are formed in the mask plate, the guide grooves are formed in the side edges of the upper ends of the alignment limiting holes, and the surface of the mask plate and the alignment limiting holes can be smoothly and obliquely connected through the arrangement of the guide grooves; the supporting salient points can be smoothly embedded in the alignment limiting holes along the guide grooves, so that only the bottoms of the supporting salient points are prevented from being in contact with the mask, the contact area of the supporting salient points and the mask is increased, the risk that the supporting structure is abraded in the alignment process is reduced, and the product packaging reliability is improved.

Description

Technical Field

[0001] This application relates to the technical field of evaporation masks, and more particularly to an improved mask. Background Art

[0002] In the manufacturing process of organic light-emitting diode (OLED) display panels, the evaporation process is one of the key steps to accurately deposit organic electro-luminescent materials onto a substrate. To achieve high-precision patterned deposition, evaporation masks are widely used. An evaporation mask is usually covered on one side of the substrate, and through the evaporation openings thereon, the evaporation material is deposited only at the predetermined positions.

[0003] During the evaporation process, the evaporation mask needs to be covered on one side of the substrate to ensure that the material is accurately evaporated to the predetermined positions. However, there are usually support structures (spacers, SPC) on the substrate, and these support structures will come into direct contact between the evaporation mask and the substrate (as Figure 1 shown). Since the evaporation mask is usually made of a metal material, and the support structure is usually made of an organic material, friction will occur during the alignment process between the mask and the support structure. This friction causes the support structure to be easily scratched, and the scratched support structure will shed particulate matter, and these particulate matters may adhere to the surface of the evaporation mask and spread to other positions as the mask moves. The presence of particulate matter will cause defects in the subsequent process of forming the encapsulation protective film. The protective film at the position where the particulate matter is located may not be able to completely isolate the intrusion of water vapor, thereby affecting the encapsulation effect and the service life of the OLED display panel.

[0004] Therefore, to solve the above problems, it is necessary to develop an improved mask to reduce the friction between the mask and the substrate support structure during the evaporation process, prevent scratching of the support structure and the generation of particulate matter, thereby improving the manufacturing quality and reliability of OLED display panels. Summary of the Utility Model

[0005] Aiming at the deficiencies of the prior art, the purpose of this application is to provide an improved mask to solve the problems raised in the above background art.

[0006] According to one aspect of the present application, an improved mask plate is used for performing an evaporation coating operation on a substrate. Support bumps are provided at the bottom of the substrate, and the support bumps are hemispherical structures. The support bumps are used to support the mask plate when the mask plate is aligned with the substrate. Alignment limiting holes are provided at the positions of the mask plate corresponding to each support bump, and guiding grooves are formed on both sides of the upper end of each alignment limiting hole along the alignment direction. The bottom shape of the guiding groove is V-shaped. The bottoms of the guiding grooves on both sides of the alignment limiting hole are smoothly inclined along the direction towards the alignment limiting hole, and both ends of the guiding groove are smoothly connected to the surface of the mask plate. The middle of the guiding groove is smoothly connected to the side of the alignment limiting hole. When the mask plate is aligned with the substrate, the support bump can be smoothly aligned to the alignment limiting hole along the guiding groove, and the support bump is embedded in the alignment limiting hole and the bottom of the support bump contacts the upper side line of the alignment limiting hole.

[0007] Preferably, a frustum-shaped groove with a rounded bottom is provided along the circumferential direction of the upper side of the alignment limiting hole, and the upper side of the frustum-shaped groove with a rounded bottom is smoothly connected to the guiding groove. When the mask plate is aligned with the substrate, the support bump can be smoothly aligned to the alignment limiting hole along the guiding groove, the support bump is embedded in the alignment limiting hole, and the outer wall of the support bump is in tangential contact with the inner wall of the frustum-shaped groove with a rounded bottom.

[0008] Preferably, a first arc groove is provided along the circumferential direction of the upper side of the alignment limiting hole, and the upper side of the first arc groove is smoothly connected to the guiding groove. The arc radius of the first arc groove is consistent with the arc radius of the outer contour of the support bump. When the mask plate is aligned with the substrate, the support bump can be smoothly aligned to the alignment limiting hole along the guiding groove, the support bump is embedded in the alignment limiting hole, and a part of the outer side wall of the support bump is in contact with the inner wall of the first arc groove, and the bottom of the support bump is located in the alignment limiting hole.

[0009] Preferably, the alignment limiting hole is a blind hole. An arc-shaped groove II is provided on the upper side edge of the alignment limiting hole along its circumferential direction, and the upper side of the arc-shaped groove II is smoothly connected to the guiding groove. A support groove is provided on the lower end surface of the alignment limiting hole. The shape and size of the support groove are adapted to the shape and size of the center of the bottom of the support bump. The arc radius of the arc-shaped groove II is consistent with the arc radius of the outer contour of the support bump. When the mask plate and the substrate are aligned, the support bump can be smoothly aligned to the alignment limiting hole along the guiding groove. The support bump is embedded in the alignment limiting hole, and a part of the outer side wall of the support bump is in fitting contact with the inner side wall of the arc-shaped groove II, and the center of the bottom of the support bump is embedded in the support groove.

[0010] Preferably, the alignment limiting hole is a hemispherical groove. The upper side of the hemispherical groove is smoothly connected to the guiding groove. The shape and size of the hemispherical groove are adapted to the shape and size of the outer contour of the support bump. When the mask plate and the substrate are aligned, the support bump can be smoothly aligned to the hemispherical groove along the guiding groove. The support bump is embedded in the hemispherical groove, and the side walls of the two are in fitting contact.

[0011] The advantages of the present application compared with the prior art are as follows: An improved mask plate of the present application, by providing an alignment limiting hole corresponding to the position of the support bump on the mask plate and a guiding groove provided on the upper side edge of the alignment limiting hole, and the guiding groove can smoothly and obliquely connect the surface of the mask plate and the alignment limiting hole, so that when the substrate and the mask plate are aligned, the support bump can be smoothly embedded in the alignment limiting hole along the guiding groove, avoiding that only the bottom of the support bump contacts the mask plate, increasing the contact area between the support bump and the mask plate, thereby reducing the risk of wear of the support structure during the alignment process and improving the packaging reliability of the product. Description of the Drawings

[0012] Figure 1 is a schematic diagram of the matching structure of the mask plate and the substrate in the prior art.

[0013] Figure 2 is a schematic diagram of the matching structure of an improved mask plate and a substrate according to an embodiment of the present application.

[0014] Figure 3 is Figure 2 a schematic enlarged view of the structure of part A in

[0015] Figure 4 is a schematic diagram of the matching structure of an improved mask plate and a substrate according to Embodiment 2 of the present application.

[0016] Figure 5Schematic diagram of a mating structure between an improved mask plate and a substrate according to Embodiment 3 of the present application.

[0017] Figure 6 Schematic diagram of a mating structure between an improved mask plate and a substrate according to Embodiment 4 of the present application.

[0018] Figure 7 Schematic diagram of a mating structure between an improved mask plate and a substrate according to Embodiment 5 of the present application.

[0019] Reference numerals: 1, substrate; 2, support bump; 3, mask plate; 4, alignment limiting hole; 41, frustum-shaped groove; 42, first arc groove; 43, second arc groove; 44, support groove; 45, hemispherical groove; 5, guiding groove. Detailed implementation manners

[0020] In order to make the content of the present application easier to be clearly understood, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present application. It should be noted that the terms "front", "rear", "left", "right", "upper" and "lower" used in the following description refer to the directions in the Figure 2 accompanying drawings, and the terms "inner" and "outer" respectively refer to the directions towards or away from the geometric center of a specific component.

[0021] As Figure 1 shown, the support bumps 2 provided at the bottom of the substrate 1 are used to support the evaporation mask plate 3 during the evaporation process, avoiding friction caused by contact between the evaporation mask plate 3 and other structures on the substrate 1. However, in the prior art, the support bumps 2 provided at the bottom of the substrate 1 are in direct contact with the surface of the mask plate 3, and only the bottom of the protruding support bumps 2 on the substrate 1 is in point contact with the evaporation mask plate 3, with a small contact area and a large pressure. When relative displacement occurs between the evaporation mask plate 3 and the support bumps 2, it is extremely easy for the bottom of the support bumps 2 to be scratched and fall off. The fallen particulate matter may move with the evaporation mask plate 3 and spread to other positions of the substrate 1, resulting in defects in the formation of the protective film at the positions where the fallen particulate matter is located during the subsequent formation of the encapsulation protective film, and the protective film cannot completely isolate the intrusion of water vapor, affecting the product encapsulation effect.

[0022] As Figure 2 and Figure 3As shown in the figure, an improved mask plate is used to perform evaporation coating operations on the substrate 1. Support bumps 2 are provided at the bottom of the substrate 1. The support bumps 2 are hemispherical structures. The support bumps 2 are used to support the mask plate 3 when the mask plate 3 is aligned with the substrate 1. Alignment limiting holes 4 are provided at the positions of the mask plate 3 corresponding to each support bump 2. Guide grooves 5 are provided on both sides of the upper end of each alignment limiting hole 4 along the alignment direction. The alignment limiting holes 4 and the guide grooves 5 are both formed by etching. The bottom shape of the guide groove 5 is V-shaped. The bottom surfaces of the guide grooves 5 on both sides of the alignment limiting hole 4 are smoothly inclined along the direction towards the alignment limiting hole 4. Both ends of the guide groove 5 are smoothly connected to the surface of the mask plate 3. The middle part of the guide groove 5 is smoothly connected to the side of the alignment limiting hole 4. When the mask plate 3 is aligned with the substrate 1, the support bump 2 can be smoothly aligned to the alignment limiting hole 4 along the guide groove 5, and the support bump 2 is embedded in the alignment limiting hole 4 and the bottom of the support bump 2 contacts the upper side line of the alignment limiting hole 4. This setting increases the contact area between the support bump 2 and the mask plate 3, and the setting of the guide groove 5 can smoothly and obliquely connect the surface of the mask plate 3 with the alignment limiting hole 4, so that when the substrate 1 is aligned with the mask plate 3, the support bump 2 can be smoothly embedded in the alignment limiting hole 4, thereby reducing the risk of wear of the support bump 2 during the alignment process and improving the reliability of product packaging.

[0023] In another embodiment, in combination with Figure 4 , a frustum-shaped groove 41 is provided along the circumferential direction of the upper side of the alignment limiting hole 4, and the upper side of the frustum-shaped groove 41 is smoothly connected to the guide groove 5. When the mask plate 3 is aligned with the substrate 1, the support bump 2 can be smoothly aligned to the alignment limiting hole 4 along the guide groove 5. The support bump 2 is embedded in the alignment limiting hole 4 and the outer wall of the support bump 2 is in tangential contact with the inner wall of the frustum-shaped groove 41. This setting makes the mask plate 3 and the support bump 2 contact relatively smoothly after the substrate 1 and the mask plate 3 are aligned, reducing the pressure at the contact position between the support bump 2 and the mask plate 3, thereby reducing the risk of wear of the evaporation coating mask plate 3.

[0024] In another embodiment, in combination with Figure 5, an arc groove 42 is provided along the circumferential direction of the upper side edge of the alignment limiting hole 4, and the upper side of the arc groove 42 is smoothly connected to the guiding groove 5, and the arc radius of the arc groove 42 is consistent with the arc radius of the outer contour of the supporting bump 2. When the mask plate 3 and the substrate 1 are arranged in alignment, the supporting bump 2 can be smoothly aligned to the alignment limiting hole 4 along the guiding groove 5. The supporting bump 2 is embedded in the alignment limiting hole 4, and a part of the outer side wall of the supporting bump 2 is in fitting contact with the inner side wall of the arc groove 42, and the bottom of the supporting bump 2 is located in the alignment limiting hole 4. This setting makes it a surface contact between the mask plate 3 and the supporting bump 2 after the substrate 1 and the mask plate 3 are aligned, which can effectively increase the contact area between the supporting bump 2 and the evaporation mask plate 3, reduce the pressure at the contact position between the supporting bump 2 and the evaporation mask plate 3, and thus reduce the risk of wear of the evaporation mask plate 3.

[0025] In another embodiment, combined with Figure 6 , the alignment limiting hole 4 is a blind hole. An arc groove 43 is provided along the circumferential direction of the upper side edge of the alignment limiting hole 4, and the upper side of the arc groove 43 is smoothly connected to the guiding groove 5. A supporting groove 44 is provided on the lower end surface of the alignment limiting hole 4. The shape and size of the supporting groove 44 are adapted to the shape and size of the center of the bottom of the supporting bump 2, and the arc radius of the arc groove 43 is consistent with the arc radius of the outer contour of the supporting bump 2. When the mask plate 3 and the substrate 1 are arranged in alignment, the supporting bump 2 can be smoothly aligned to the alignment limiting hole 4 along the guiding groove 5. The supporting bump 2 is embedded in the alignment limiting hole 4, and a part of the outer side wall of the supporting bump 2 is in fitting contact with the inner side wall of the arc groove 43, and the center of the bottom of the supporting bump 2 is embedded in the supporting groove 44. This setting makes it a surface contact between both the side wall and the bottom center of the supporting bump 2 and the mask plate 3 after the substrate 1 and the mask plate 3 are aligned, forming two surface contacts, which can further increase the contact area between the supporting bump 2 and the evaporation mask plate 3, improve the supporting effect on the mask plate 3, reduce the pressure at the contact position between the supporting bump 2 and the evaporation mask plate 3, and thus reduce the risk of wear of the evaporation mask plate 3.

[0026] In another embodiment, combined with Figure 7 , the alignment limiting hole 4 is a hemispherical groove 45. The upper side of the hemispherical groove 45 is smoothly connected to the guiding groove 5. The shape and size of the hemispherical groove 45 are adapted to the shape and size of the outer contour of the supporting bump 2. When the mask plate 3 and the substrate 1 are arranged in alignment, the supporting bump 2 can be smoothly aligned to the hemispherical groove 45 along the guiding groove 5. The supporting bump 2 is embedded in the hemispherical groove 45 and the side walls of both are in fitting contact. This setting makes it a full surface contact between the supporting bump 2 and the mask plate 3 after the substrate 1 and the mask plate 3 are aligned, increases the contact area between the supporting bump 2 and the evaporation mask plate 3, reduces the pressure at the contact position between the supporting bump 2 and the evaporation mask plate 3, and thus reduces the risk of wear of the evaporation mask plate 3.

[0027] In summary, by providing alignment limit holes 4 corresponding to the positions of the support bumps 2 on the mask plate 3 and providing guiding grooves 5 on the upper side edges of the alignment limit holes 4, and the arrangement of the guiding grooves 5 can smoothly and obliquely connect the surface of the mask plate 3 with the alignment limit holes 4, so that when the substrate 1 is aligned with the mask plate 3, the support bumps 2 can be smoothly inserted into the alignment limit holes 4 along the guiding grooves 5, preventing the support bumps 2 from only contacting the mask plate 3 at the bottom, increasing the contact area between the support bumps 2 and the mask plate 3, thereby reducing the risk of wear of the support structure during the alignment process and improving the product packaging reliability.

[0028] The above embodiments are only used to illustrate the technical solutions of the embodiments of the present application, and are not intended to limit the same. Although the embodiments of the present application have been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that without departing from the spirit and scope defined by the claims of the present application, they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features.

Claims

1. An improved mask plate, used for performing a vapor deposition operation on a substrate (1), wherein a supporting protrusion (2) is provided at the bottom of the substrate (1), wherein the supporting protrusion (2) is a hemispherical structure, and wherein the supporting protrusion (2) is used for supporting the mask plate (3) when the mask plate (3) is aligned with the substrate (1), characterized in that: A positioning limiting hole (4) is provided on the mask plate (3) at the position corresponding to each of the supporting protrusions (2), and guide grooves (5) are provided on both sides of the upper end of each of the positioning limiting holes (4) along the positioning direction, the groove bottom shape of the guide groove (5) is V-shaped, the groove bottoms of the guide grooves (5) located on both sides of the positioning limiting holes (4) are smoothly inclined along the direction toward the positioning limiting holes (4), and both ends of the guide grooves (5) are smoothly connected to the surface of the mask plate (3), and the middle of the guide grooves (5) is smoothly connected to the side of the positioning limiting hole (4). When the mask plate (3) and the substrate (1) are aligned, the supporting protrusions (2) can be smoothly aligned to the positioning limiting holes (4) along the guide grooves (5), and the supporting protrusions (2) are embedded in the positioning limiting holes (4) and the bottom of the supporting protrusions (2) is in contact with the side line of the upper end of the positioning limiting holes (4).

2. The improved mask according to claim 1, characterized in that: An inverted truncated cone-shaped groove (41) is arranged along the circumference of the upper side edge of the alignment limiting hole (4), and the upper side edge of the inverted truncated cone-shaped groove (41) is smoothly connected to the guide groove (5). When the mask plate (3) and the substrate (1) are aligned, the support protrusion (2) can be smoothly aligned to the alignment limiting hole (4) along the guide groove (5), and the support protrusion (2) is embedded in the alignment limiting hole (4) and the outer side wall of the support protrusion (2) is in tangential contact with the inner side wall of the inverted truncated cone-shaped groove (41).

3. The improved mask according to claim 1, characterized in that: A circular arc groove (42) is provided along the circumference of the upper side edge of the alignment limiting hole (4), and the upper side edge of the circular arc groove (42) is smoothly connected to the guide groove (5), and the arc radius of the circular arc groove (42) is consistent with the arc radius of the outer contour of the supporting protrusion (2). When the mask plate (3) and the substrate (1) are aligned, the supporting protrusion (2) can be smoothly aligned to the alignment limiting hole (4) along the guide groove (5), the supporting protrusion (2) is embedded in the alignment limiting hole (4), and part of the outer side wall of the supporting protrusion (2) is in contact with the inner side wall of the circular arc groove (42), and the bottom of the supporting protrusion (2) is located in the alignment limiting hole (4).

4. The improved mask according to claim 1, characterized in that: The alignment limiting hole (4) is a blind hole, and a second circular arc groove (43) is arranged along the circumference of the upper side edge of the alignment limiting hole (4), and the upper side edge of the second circular arc groove (43) is smoothly connected to the guide groove (5), and a supporting groove (44) is arranged on the lower end surface of the alignment limiting hole (4), and the shape and size of the supporting groove (44) are matched with the shape and size of the bottom center of the supporting protrusion (2), and the arc radius of the second circular arc groove (43) is the same as that of the supporting protrusion (2). ) is consistent with the arc radius of the outer contour, when the mask plate (3) and the substrate (1) are aligned, the supporting protrusion (2) can be smoothly aligned to the alignment limiting hole (4) along the guide groove (5), the supporting protrusion (2) is embedded in the alignment limiting hole (4) and part of the outer side wall of the supporting protrusion (2) is in contact with the inner side wall of the second circular arc groove (43), and the bottom center of the supporting protrusion (2) is embedded in the supporting groove (44).

5. The improved mask according to claim 1, characterized in that: The alignment limiting hole (4) is a hemispherical groove (45), the upper side of the hemispherical groove (45) is smoothly connected to the guide groove (5), the shape and size of the hemispherical groove (45) are compatible with the shape and size of the outer contour of the supporting protrusion (2), when the mask plate (3) and the substrate (1) are aligned, the supporting protrusion (2) can be smoothly aligned to the hemispherical groove (45) along the guide groove (5), and the supporting protrusion (2) is embedded in the hemispherical groove (45) and the side walls of the two are in contact with each other.

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