Mask frame, manufacturing method and mask plate assembly

Abstract

The invention provides a mask frame, a manufacturing method and a mask plate assembly. The manufacturing method comprises the steps that a plate-shaped base material is provided, and the base material is provided with a first surface and a second surface which are opposite to each other; a first groove is formed, and the first groove with the depth direction facing the first surface is formed in the second surface; forming a supporting part, and forming a plurality of openings which penetrate through the first surface and are arranged in an array in the first groove so as to form the supporting part; wherein the supporting part comprises rib parts between the openings and peripheral supporting parts surrounding the opening array, and the peripheral supporting parts are located in the first groove. Compared with the prior art, the manufacturing method provided by the embodiment of the invention, the mask frame obtained by the manufacturing method and the mask plate assembly comprising the mask frame have the advantages of high production efficiency, high product precision and capability of effectively relieving the sagging phenomenon of the mask plate.

Description

Technical Field

[0001] The present disclosure relates to the technical field of OLED display panel manufacturing, and in particular to a mask frame and a manufacturing method thereof, and a mask plate assembly. Background Art

[0002] The mask plate assembly is an important tool in the preparation process of OLED (organic light-emitting diode) display panels. It is mainly used for evaporation of organic materials, or to limit the deposition area of ​​film materials in the process of forming an encapsulation layer.

[0003] In the prior art, the mask plate assembly usually includes a mask frame in the form of a rectangular frame, and the mask plate is tightened and fixed to the mask frame through a stretching step. Although the sagging of the mask plate can be suppressed by applying sufficient tension, for larger mask plates, the sagging amount of the mask plate after stretching is still difficult to meet the requirements.

[0004] The sagging of the mask plate causes the morphology of the patterns and openings thereon to deteriorate, causing the pixels formed by the mask plate assembly when in use, or the film layers such as the encapsulation layer and the universal layer to be misaligned, directly affecting the quality of the final product, such as a display panel.

[0005] To improve the sagging problem, the prior art practice is to set a support mesh or support bar between the mask plate and the mask frame to support the mask plate, and to lift the sagging area of ​​the mask plate by the support mesh or support bar to reduce the sagging amount of the mask plate.

[0006] However, the support mesh and support bars also need to be fixed to the mask frame through a stretching step, and the stretching step requires high-precision alignment operations, which are difficult, time-consuming, and have a low yield rate. Due to the increase in working steps, the overall production efficiency of the mask plate is reduced to a certain extent.

[0007] The weight of the support mesh or support bar itself causes it to sag, so its effect in reducing the sagging of the mask plate is limited. More importantly, despite the execution of complex alignment operations, the support mesh or support bar inevitably has position accuracy deviations. In addition, there will also be position deviations in the process of stretching the mask plate. The superposition of these two sets of deviations leads to a further reduction in the overall accuracy of the mask plate assembly. Summary of the invention

[0008] In order to solve or improve the above problems existing in the prior art, a first aspect of an embodiment of the present disclosure provides a method for manufacturing a mask frame, the manufacturing method comprising:

[0009] Providing a substrate, the substrate is in a plate shape and has a first surface and a second surface opposite to each other;

[0010] forming a first groove, wherein a first groove is formed on the second surface in a depth direction facing the first surface;

[0011] Forming a support portion, forming a plurality of openings in the first groove that penetrate to the first surface and are arranged in an array to form the support portion;

[0012] The support portion includes ribs between the openings and a peripheral support portion surrounding the opening array, and the peripheral support portion is located in the first groove.

[0013] In the aforementioned technical solution, the prepared mask frame has a support portion integrally formed with the outer frame, which replaces the support mesh and support bars arranged between the mask plate and the mask frame in the prior art. Compared with the prior art, there is no need to perform the difficult step of stretching the support mesh or support bars, thereby improving production efficiency.

[0014] On the other hand, since the entire mask frame, including the support part and its ribs, and the outer frame are integrally formed from the same substrate, the precision between its various parts far exceeds the splicing form in the prior art, and the accumulation of errors when each component is stretched separately is avoided, the overall accuracy of the product is improved.

[0015] Similarly, the ribs in the support portion are integrally formed, thus avoiding the dislocation of the spliced ​​ribs at the intersections in the prior art. After the mask plate is installed, it helps to reduce the additional sagging of the mask plate caused by the dislocation of the ribs at the intersections.

[0016] Optionally, the preparation method further includes:

[0017] Forming a second groove, forming a plurality of second grooves at the bottom of the first groove with the depth direction facing the first surface, and the plurality of second grooves are arranged in an array;

[0018] Forming the support portion further includes:

[0019] The plurality of openings are disposed at the bottoms of the plurality of second grooves in a one-to-one correspondence.

[0020] In the aforementioned optional solution, the second groove is used to form a convex portion on the support portion between the openings, and the convex portion is formed on the rib portion and becomes a part of the rib portion.

[0021] Furthermore, the preparation method also includes:

[0022] A third groove is formed. A third groove in the shape of a long strip is formed between adjacent rows and adjacent columns of the second groove array. The width of the third groove is smaller than the spacing between adjacent second grooves.

[0023] The function of the third groove is to further divide the convex portion on the aforementioned rib portion, so that two parallel convex portions are formed on one rib portion.

[0024] The aforementioned second groove and third groove can both reduce the thickness and weight of the support part, and the convex parts formed between adjacent second grooves and between the third groove and the second groove can improve the anti-deformation ability of the opening and the supporting ability of the support part to a certain extent. In addition, the second groove can also reduce the shielding of the support part on the evaporation material.

[0025] Optionally, forming the third grooves includes forming a plurality of spaced third grooves between adjacent rows and between adjacent columns of the second groove array.

[0026] The third grooves are arranged at intervals so that the convex portion formed between the third grooves and the second grooves is connected to form a whole, so as to improve the support of the convex portion and further improve the ability of the supporting portion to resist sagging.

[0027] Optionally, the preparation method further includes:

[0028] Forming a fourth groove, forming a plurality of fourth grooves on the first surface with the depth direction facing the second surface, and the plurality of fourth grooves are arranged in an array; the fourth grooves are used to fix the mask plate;

[0029] Forming the support portion further includes:

[0030] The plurality of openings are disposed in the plurality of fourth grooves in a one-to-one correspondence.

[0031] The fourth groove is used to fix the mask plate, and the mask plate can be embedded therein for installation, so as to eliminate or reduce the height difference between the upper surface of the fixed mask plate and the upper surface of the mask frame, thereby improving the flatness of the overall upper surface of the mask plate assembly.

[0032] At the same time, the fourth groove formed by means such as etching has a higher precision, and the fourth groove can play a role in positioning the mask plate, thereby improving the installation precision of the mask plate.

[0033] Furthermore, the preparation method also includes:

[0034] forming a fifth groove, wherein a plurality of fifth grooves are respectively formed at the bottoms of the plurality of fourth grooves, and the area of ​​the fifth grooves is smaller than that of the fourth grooves;

[0035] Forming the support portion further includes:

[0036] The plurality of openings are disposed in the plurality of fifth grooves in a one-to-one correspondence.

[0037] The fifth groove is intended to eliminate or reduce the adverse effects of foreign matter at the edge of the opening on the flatness of the mask plate. The foreign matter includes burrs or oil residues. In the presence of foreign matter, the joint of the edge of the mask plate may bulge or warp due to the inclusion of foreign matter after being fitted around the opening of the mask frame, causing local deformation of the mask plate, deterioration of the morphology of its pattern or opening, and affecting the overall accuracy.

[0038] Optionally, forming the fourth groove further includes:

[0039] forming a fourth groove by turning, milling, honing or grinding;

[0040] Forming the fifth groove further includes:

[0041] forming a fifth groove by turning, milling, honing or grinding;

[0042] The fourth groove and the fifth groove are formed before the first groove is formed.

[0043] After the first groove is processed, the remaining portion for forming the support portion is relatively thin, and working on it is likely to cause unacceptable deformation. This optional solution allows the fourth groove and the fifth groove to be formed before the first groove is formed, in order to prevent the aforementioned deformation.

[0044] Optionally, the fourth groove and the fifth groove are formed after the first groove is formed, and support is provided at the bottom of the first groove when the fourth groove and the fifth groove are formed to prevent deformation due to single-sided force when the fourth groove and the fifth groove are formed.

[0045] Optionally, the other grooves except the first groove are formed by etching. By etching, it is also possible to avoid applying force to the thin bottom of the first groove to prevent its deformation.

[0046] Optionally, in forming the support portion, a method of forming the opening includes:

[0047] Forming a through hole penetrating the first groove and the first surface by laser cutting;

[0048] The vias are modified by etching as follows to obtain openings:

[0049] Enlarge the through hole to a preset value;

[0050] trimming the inner side surface of the through hole into a target shape, wherein the target shape includes a vertical plane or an inclined plane;

[0051] Correct the through hole to the preset accuracy.

[0052] The aforementioned optional solution for forming the opening can obtain an opening with higher precision.

[0053] According to a second aspect of the embodiments of the present disclosure, a mask frame is provided. The mask frame is manufactured by the manufacturing method described in the technical solution of the first aspect and any optional solution thereof.

[0054] According to a third aspect of the embodiments of the present disclosure, a mask plate assembly is provided, including:

[0055] The mask frame as described in the second aspect.

[0056] A plurality of mask plates, wherein the mask plates include a pattern area and a joint portion surrounding an edge of the mask plate;

[0057] A plurality of mask plates are arranged on one side of the first surface of the mask frame, corresponding to the plurality of openings one by one, and the joint portion of the mask plate is joined to the supporting portion of the mask frame.

[0058] In an optional solution, the mask frame is specifically manufactured by a method comprising the following steps:

[0059] Forming a fourth groove, forming a plurality of fourth grooves on the first surface with the depth direction facing the second surface, and the plurality of fourth grooves are arranged in an array; the fourth grooves are used to fix the mask plate;

[0060] Forming the support portion further includes:

[0061] The plurality of openings are disposed in the plurality of fourth grooves in a one-to-one correspondence.

[0062] In this optional solution, at least a portion of the joint portion of the mask plate is embedded in the fourth groove and is joined with the fourth groove.

[0063] Optionally, the mask plate further includes a transition area between the pattern area and the bonding portion;

[0064] The purpose of setting the transition zone is to eliminate or reduce the shadow area generated at the edge of the panel during evaporation (the film layer area with uneven film thickness and a thickness significantly smaller than the thickness of the middle effective area).

[0065] Preferred:

[0066] The width S of the transition zone satisfies:

[0067] 0.25≤h / S≤1.7,

[0068] Wherein, h is the thickness of the inner edge of the opening of the mask frame.

[0069] Further preferably, the width S of the transition zone satisfies:

[0070] 0.25≤h / S≤1.5.

[0071] Further preferably, the width S of the transition zone satisfies:

[0072] 0.6≤h / S≤1.

[0073] The thickness of the support portion determines its strength, so it should not be too thin, otherwise it will cause a large degree of sagging. If it is too thick, it will block the evaporation material during the evaporation process, thereby generating the aforementioned shadow area.

[0074] In the above scheme, the above transition zone is set on the mask plate, and under the premise that the support portion maintains sufficient thickness, the shielding of the evaporation material by the support portion can be reduced, ensuring that the evaporation material can enter the pattern area of ​​the mask plate in sufficient quantity, thereby improving the evaporation quality. Due to the setting of the transition zone, the inner side of the opening can be made into a vertical plane (with the same size of the opening at the top and bottom) or an inclined plane / arc surface (with the opening being larger at the bottom and smaller at the top) without restriction.

[0075] The mask plate assembly provided in the embodiments of the present disclosure can be used as an FMM mask plate (Fine Metal Mask) for forming pixels in a vapor deposition process, or as a CMM mask plate (Common Metal Mask) for forming a common layer, or as an encapsulation mask plate for forming an encapsulation layer, depending on the form of the mask plate pattern area.

[0076] Therefore, optionally, the pattern area of ​​the mask plate has a plurality of pixel through holes, and the mask plate assembly is used to form pixels in the OLED production process, as the aforementioned FMM mask plate;

[0077] Alternatively, the pattern area of ​​the mask has at least one through hole, and the mask assembly is used to form a universal layer in the OLED production process, as the aforementioned CMM mask;

[0078] Or optionally, the pattern area of ​​the mask plate has at least one through hole, and the mask plate assembly is used to form an encapsulation layer in the OLED production process, serving as the aforementioned encapsulation mask plate.

[0079] In summary, the manufacturing method provided in the embodiments of the present disclosure, the mask frame obtained by the manufacturing method, and the mask plate assembly including the mask frame have the advantages of high production efficiency, high product precision and effective alleviation of the mask plate sagging phenomenon compared to the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0080] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure or the background technology, the drawings required for use in the embodiments of the present disclosure or the background technology will be described below.

[0081] Figure 1 is a schematic diagram of a process of forming a first groove on a substrate in an embodiment of the present disclosure;

[0082] Figure 2 is a schematic diagram of a process of forming an opening at the bottom of the first groove to form a support portion in an embodiment of the present disclosure (observed from the second surface direction);

[0083] Figure 3is a schematic diagram of a process of forming an opening at the bottom of the first groove to form a support portion in an embodiment of the present disclosure (observed from the first surface direction);

[0084] Figure 4 is a schematic diagram of a process of further forming a second groove at the bottom of the first groove in an embodiment of the present disclosure;

[0085] Figure 5 is a schematic diagram of a process for forming an opening at the bottom of the second groove in an embodiment of the present disclosure;

[0086] Figure 6 is a schematic cross-sectional view of a rib having a convex portion formed by a second groove in an embodiment of the present disclosure;

[0087] Figure 7 The shape and position relationship of the second groove and the third groove in the embodiment are shown;

[0088] Figure 8 Another form of the third groove shape in the embodiment is shown;

[0089] Fig. 9 A schematic cross-sectional view of a rib having a plurality of protrusions formed by a third groove in an embodiment of the present disclosure is shown;

[0090] Fig.10 is a schematic diagram of a process of forming a fourth groove on the first surface of the substrate in an embodiment of the present disclosure;

[0091] Fig.11 is a schematic diagram of a process of forming an opening at the bottom of the fourth groove in an embodiment of the present disclosure;

[0092] Fig.12 is a partial cross-sectional view of a support portion having a fourth groove in an embodiment of the present disclosure;

[0093] Fig.13 is a partial cross-sectional view of a support portion having a fourth groove and a fifth groove in an embodiment of the present disclosure;

[0094] Fig.14 is a schematic diagram of a mask plate in an embodiment of the present disclosure;

[0095] Fig.15 The figure shows a bonding method of a mask plate on a mask frame according to an embodiment of the present disclosure;

[0096] Fig.16 is an overall schematic diagram of a mask plate assembly provided by an embodiment of the present disclosure;

[0097] Fig.17 3 is a cross-sectional view of the mask plate joined to the support portion in the embodiment of the present disclosure, showing the width of the transition zone, the thickness of the inner edge of the opening, and the cross-sectional shape of the pixel through hole.

[0098] Note in the figure:

[0099] 01: first surface, 02: second surface;

[0100] 11: first groove, 12: second groove, 13: third groove, 14: fourth groove, 15: fifth groove;

[0101] 20: Open mouth;

[0102] 30: support portion, 31 peripheral support portion, 32 rib portion;

[0103] 321: convex part;

[0104] 40: mask plate, 41: pattern area, 42: joint part, 43: transition area;

[0105] 411: Pixel through hole. DETAILED DESCRIPTION

[0106] In the present specification, it will also be understood that when an element is referred to as being relative to other elements, such as being "connected to" other elements, the one element may be directly connected to or directly coupled to the one element, or there may also be a third element in between; in addition, in the embodiments of the present disclosure, "connection" may specifically be a structural connection, and "bonding" specifically refers to welding, bonding or similar fixing methods.

[0107] In the embodiments of the present disclosure, unless otherwise specified, the area of ​​the groove specifically refers to the area of ​​the bottom surface of the groove, that is, the projection area in the depth direction of the groove, and "arranged in the groove" specifically refers to being arranged at the bottom of the groove, or at the bottom of other grooves nested in the groove.

[0108] It should be understood that in order to accurately disclose the structures described in the embodiments in the black and white drawings, in the drawings of the present disclosure, the area where the filling pattern is drawn or partially drawn indicates that the area is a solid, rather than an opening, a through hole or a similar structure, for example Figure 1 The portion indicated by reference numeral 11 is the bottom plane of the groove, not the opening.

[0109] The present disclosure will now be described more fully below with reference to the accompanying drawings, however, the present disclosure can be implemented in many different ways and should not be construed as being limited to the embodiments set forth herein. On the contrary, providing these embodiments herein will make the present disclosure more detailed and complete, and fully convey the scope of the present disclosure to those skilled in the art. The same reference numerals throughout the text represent the same objects.

[0110] In order to at least solve or improve the problems existing in the above-mentioned prior art, the present disclosure first provides a method for manufacturing a mask frame, and the manufacturing method includes the following steps:

[0111] A substrate is provided. The substrate is in a plate shape and has a first surface and a second surface opposite to each other.

[0112] Typically, the substrate is a rectangular metal plate, whose first surface and second surface are parallel to each other. The material of the substrate is preferably a metal with low expansion properties, for example, it can be selected from: Invar36 alloy, Super Invar32 alloy, SUS304 or SUS420.

[0113] A first groove is formed, such as Figure 1 As shown, a first groove 11 is formed on the second surface 02 of the substrate plate with its depth direction facing the first surface.

[0114] According to an embodiment of the present disclosure, the first groove 11 is a rectangular groove, and the bottom surface is a plane parallel to both the first surface and the second surface.

[0115] Based on the formation of the first groove 11, as Figure 1 As shown, a thinner bottom of the first groove 11 and an outer frame surrounding the bottom of the first groove 11 are formed on the substrate, and the outer frame serves as the outer frame of the mask frame product formed. Since this embodiment is a subtractive processing, the thickness of the bottom of the first groove 11 determines the maximum thickness of the support portion formed subsequently.

[0116] Forming a support portion, such as Figure 2 and Figure 3 As shown, a plurality of openings 20 are formed in the first groove 11 and are arranged in an array to form a support portion 30, thereby forming the basic configuration of the mask frame provided by the embodiment of the present disclosure, that is, the support portion 30 and the outer frame around the support portion 30 are integrally formed by subtractive processing of a substrate. One or more mask plates can be joined to the support portion 30, and the pattern area of ​​the mask plate is exposed in the aforementioned opening 20 to form a mask plate assembly.

[0117] like Figure 2 and Figure 3 As shown, the support portion 30 includes ribs 32 between the openings 20 and a peripheral support portion 31 surrounding the array of openings 20 , and the peripheral support portion 31 is located in the first groove 11 .

[0118] like Figure 2 and Figure 3 As shown, the outermost opening of the array is at a certain distance from the outer frame, that is, there is a peripheral support portion 31 between them, which can prevent the outer frame from blocking the evaporation material and forming a shadow on the product.

[0119] In a typical embodiment, the openings 20 are arranged in a rectangular array including a plurality of rows and a plurality of columns. The ribs 32 between the openings include a plurality of first ribs extending in the row direction and a plurality of second ribs extending in the column direction. The first ribs are arranged to cross the second ribs perpendicularly.

[0120] In the aforementioned embodiment, the mask frame manufactured by the method has a support portion 30 formed integrally with the outer frame, which replaces the support bar or support mesh in the prior art, and does not require a difficult mesh stretching step, thereby improving production efficiency.

[0121] On the other hand, since the entire mask frame, including the support portion 30 and the ribs 32 therein, and the outer frame are integrally formed from the same substrate, the accuracy between its various parts far exceeds that of the splicing form, and the accumulation of errors when each component is stretched separately is avoided, the overall accuracy of the product is improved.

[0122] Similarly, the first rib and the second rib, which are perpendicular to each other, are integrally formed, thus avoiding the dislocation of the spliced ​​ribs at the intersection. After the mask plate is installed, it helps to reduce the additional sagging of the mask plate caused by the dislocation of the ribs at the intersection.

[0123] In a preferred embodiment, the manufacturing method further comprises:

[0124] A second groove is formed, such as Figure 4 As shown, an array of second grooves 12 with a depth direction facing the first surface is formed at the bottom of the first grooves 11.

[0125] In the typical embodiment, the bottom surface of the second groove 12 is also parallel to both the first surface and the second surface.

[0126] Correspondingly, Figure 5 As shown, the plurality of openings 20 are disposed at the bottoms of the plurality of second grooves 12 in a one-to-one correspondence.

[0127] like Figure 6 As shown in the cross-sectional view of the rib in FIG. 1 , the second groove 12 is used to form a convex portion 321 on the support portion between the openings. The convex portion 321 is formed on the rib 32 and becomes a part of the rib 32 .

[0128] The second groove 12 acts on the peripheral support portion 31 at the same time, forming a step-like shape on the inner side of the peripheral support portion 31 , which can avoid or alleviate the generation of a shadow area near the peripheral support portion 31 .

[0129] Explanatory note, in the prior art, support meshes and support bars are generally made of Invar (an ideal composition of 36% nickel and 63.8% iron with an extremely low thermal expansion coefficient) sheets. The Invar sheet itself is very thin and is prone to sinking and deforming even when stretched. It is impossible to increase its strength by machining protrusions thereon by grooving. The method of attaching (such as welding) protrusions thereon is more difficult to manufacture. Moreover, when stretching the support meshes and support bars with protrusions thereon, uneven force is easily caused, making it difficult to obtain a flat support mesh.

[0130] Compared with the prior art, the protrusion 321 formed by the second groove 12 and integrally formed with the rib 32 does not have such a disadvantage.

[0131] In a preferred embodiment, the manufacturing method further comprises:

[0132] A third groove is formed, such as Figure 7 As shown, between adjacent rows and columns of the second groove 12 array, long strip-shaped third grooves 13 are formed respectively, and the width of the third grooves 13 is smaller than the spacing between adjacent second grooves 12 .

[0133] The function of the third groove 13 is as follows: Fig. 9 As shown, the convex portion 321 on the aforementioned rib is further divided, so that two parallel convex portions 321 are formed on one rib 32 .

[0134] In a typical embodiment, Figure 7 As shown, both ends of the third groove 13 are flush with the edges of the second groove 12 array, in other words, the third groove 13 does not extend to the peripheral support portion 31. This is because the peripheral support portion 31 is far from the center of the mask frame, and there is no need to form more convex portions to reduce weight and increase strength. On the contrary, grooving on the peripheral support portion 31 may weaken its strength and have an adverse effect.

[0135] The function of the protrusion 321 in the above embodiment is to reduce the thickness of the edge of the support portion to reduce the shielding of the vapor deposition material by the support portion, and to enhance the strength of the support portion, especially the rib 32, to prevent the support portion from sagging and deforming.

[0136] The aforementioned second groove and third groove can both reduce the thickness and weight of the support part, and the convex parts formed between adjacent second grooves and between the third groove and the second groove can improve the anti-deformation ability of the opening and the supporting ability of the support part to a certain extent. In addition, the second groove can also reduce the shielding of the support part on the evaporation material.

[0137] Optionally, a third groove is formed, such as Figure 8As shown, a plurality of spaced third grooves 13 are formed between adjacent rows and adjacent columns of the second groove 12 array.

[0138] In a typical embodiment, Figure 8 As shown, a plurality of third grooves 13 are spaced apart at the intersection of the first rib and the second rib. In other words, no third groove 13 is formed at the intersection of the first rib and the second rib.

[0139] In the embodiment, the third grooves are arranged at intervals so that the convex portion formed between the third grooves and the second grooves is connected to form a whole, so as to improve the support of the convex portion and further improve the ability of the support portion to resist sagging.

[0140] In an embodiment of the present disclosure, the depths of the third groove and the second groove may be the same or different.

[0141] In a preferred embodiment, the manufacturing method further comprises:

[0142] A fourth groove is formed, such as Fig.10 As shown, the substrate is turned over to form a plurality of fourth grooves 14 on the first surface 01 with the depth direction facing the second surface, and the plurality of fourth grooves 14 are arranged in an array; wherein the bottom plane of the fourth grooves 14 is a surface parallel to both the first surface 01 and the second surface 02 .

[0143] The fourth groove 14 is used to fix the mask plate.

[0144] Correspondingly, forming the support portion also includes:

[0145] like Fig.11 As shown, the plurality of openings 20 are disposed in the plurality of fourth grooves 14 in a one-to-one correspondence.

[0146] In the embodiment, the fourth groove 14 is used to fix the mask plate. The cross section after the mask plate is installed is as follows: Fig.17 As shown, the mask plate can be embedded therein for installation, so as to eliminate or reduce the height difference between the upper surface of the fixed mask plate and the upper surface of the mask frame, thereby improving the flatness of the overall upper surface of the mask plate assembly.

[0147] At the same time, the fourth groove formed by etching or other means has high precision, and the fourth groove can play a role in accurately positioning the mask plate, improve the installation accuracy of the mask plate, and reduce the difficulty of the mask plate stretching and bonding operations.

[0148] In a preferred embodiment, the manufacturing method further comprises:

[0149] The fifth groove is formed, as shown in the cross section Fig.13 As shown, a plurality of fifth grooves 15 are respectively formed at the bottom of the plurality of fourth grooves 14, and the bottom surface area of ​​the fifth groove is smaller than that of the fourth groove;

[0150] Correspondingly, forming the support portion also includes:

[0151] The plurality of openings 20 are disposed in the plurality of fifth grooves 15 in a one-to-one correspondence.

[0152] The fifth groove 15 is intended to eliminate or reduce the adverse effects of foreign matter at the edge of the opening on the flatness of the mask plate. The foreign matter includes burrs or oil residues. In the presence of foreign matter, the joint of the edge of the mask plate may bulge or warp due to the inclusion of foreign matter after being fitted around the opening of the mask frame, causing local deformation of the mask plate, deterioration of the morphology of its pattern or opening, and affecting the overall accuracy.

[0153] In a typical embodiment, a method of forming the fourth groove includes:

[0154] The fourth groove is formed by turning, milling, honing or grinding.

[0155] In a typical embodiment, a method of forming the fifth groove includes:

[0156] forming a fifth groove by turning, milling, honing or grinding;

[0157] In a preferred embodiment, when the fourth groove and the fifth groove are formed by the aforementioned machining method, the formation sequence thereof is performed before the formation of the first groove.

[0158] This is because after the first groove is processed, the remaining portion for forming the support portion is relatively thin, and working on it is likely to cause unacceptable deformation, or even damage the bottom of the first groove. In this embodiment, the fourth groove and the fifth groove are formed before the first groove is formed, in order to prevent the above-mentioned deformation or damage from occurring.

[0159] In another optional embodiment, the process of forming the fourth groove and the process of forming the fifth groove may also be performed after forming the first groove, but support is required at the bottom of the first groove when forming the fourth groove and the fifth groove to prevent the bottom of the first groove from being deformed due to single-sided force when forming the fourth groove and the fifth groove.

[0160] In a typical embodiment, since the first groove is deep and difficult to process by etching, the first groove is still formed by mechanical processing such as milling, and the other grooves except the first groove are formed by etching. Etching can also avoid applying force to the thin bottom of the first groove to prevent its deformation.

[0161] In one embodiment, all grooves are formed by turning, milling, honing or grinding.

[0162] In a typical embodiment, the first groove, the second groove, the third groove, the fourth groove and the fifth groove exist at the same time.

[0163] In a typical embodiment, in forming the support portion, the method for forming the opening specifically includes the following steps:

[0164] Forming a through hole penetrating the first groove and the first surface by laser cutting, wherein the through hole has substantially the same size and shape as the opening;

[0165] The vias are modified by etching as follows to obtain openings:

[0166] Enlarge the through hole to a preset value;

[0167] trimming the inner side surface of the through hole into a target shape, wherein the target shape includes a vertical plane or an inclined plane;

[0168] Correct the through hole to the preset accuracy.

[0169] The solution for forming the opening in the aforementioned embodiment can obtain an opening with higher precision.

[0170] The present disclosure further provides an embodiment of a mask frame, and the mask frame is manufactured by the manufacturing method described in the aforementioned manufacturing method embodiment and any one of its preferred and optional embodiments.

[0171] Therefore, the mask frame in the embodiment has multiple or all structural features described in the above method embodiments. Typically, the mask frame includes a thick outer frame, and a first groove 11 located inside the outer frame, and an array of openings 20 are arranged at the bottom of the first groove 11. At the same time, all structures in the mask frame are integrally constructed. The mask frame further optionally has various structural features formed by the second to fifth grooves described in the above embodiments.

[0172] The present disclosure further provides an embodiment of a mask plate assembly, such as Fig.16 As shown, the mask assembly includes:

[0173] The mask frame as described in the above embodiment.

[0174] A plurality of mask plates 40, such as Fig.14 As shown, the mask plate 40 includes a pattern area 41 and a joint portion 42 surrounding the edge of the mask plate 40 .

[0175] like Fig.15 As shown, a plurality of mask plates 40 are respectively disposed on one side of the first surface 01 of the mask frame, corresponding to the plurality of openings one by one, and the joint portion of the mask plate is joined to the supporting portion of the mask frame.

[0176] In a typical embodiment, the mask frame is used, and its manufacturing method includes the aforementioned step of forming the fourth groove, such as Fig.17 As shown, at least a portion of the engaging portion 42 of the mask plate is embedded in the fourth groove 14 and engaged with the fourth groove 14 .

[0177] In a typical embodiment, Fig.14 As shown, the mask plate 40 further includes a transition area 43 between the pattern area 41 and the bonding portion 42;

[0178] The purpose of setting the transition zone 43 is to eliminate or reduce the shadow area (the film layer area with uneven film thickness and a thickness significantly smaller than the thickness of the middle effective area) generated at the edge of the panel during evaporation.

[0179] like Fig.17 As shown, the selection of the width S of the transition zone is related to the thickness h of the inner edge of the opening of the mask frame.

[0180] In a preferred embodiment:

[0181] The width S of the transition zone satisfies:

[0182] 0.25≤h / S≤1.7.

[0183] Further preferably, the width S of the transition zone satisfies:

[0184] 0.25≤h / S≤1.5.

[0185] Further preferably, the width S of the transition zone satisfies:

[0186] 0.6≤h / S≤1.

[0187] The thickness of the support portion determines its strength, so it should not be too thin, otherwise it will cause a large degree of sagging. If it is too thick, it will block the evaporation material during the evaporation process, thereby generating the aforementioned shadow area.

[0188] In the above scheme, the above transition zone is set on the mask plate, and under the premise that the support portion maintains a sufficient thickness, the shielding of the evaporation material by the support portion can be reduced, ensuring that the evaporation material can enter the pattern area of ​​the mask plate in sufficient quantity, thereby improving the evaporation quality. Due to the setting of the transition zone, the inner side of the opening can be made into a vertical plane (with the same size at the top and bottom of the opening) or an inclined plane (with the opening being larger at the bottom and smaller at the top) without restriction.

[0189] In the embodiment of the present disclosure, during use, one side of the first surface 01 of the mask plate assembly is used to be attached to the substrate of the display panel.

[0190] The mask assembly provided in the embodiments of the present disclosure can be used as an FMM mask for forming pixels in an evaporation process, or as a CMM mask for forming a universal layer, depending on the form of the mask pattern area therein.

[0191] In one embodiment, Fig.14 and Fig.17 As shown, the pattern area 41 of the mask plate 40 has a plurality of pixel through holes 411, and the mask plate assembly is used to form pixels in the OLED production process, as the aforementioned FMM mask plate;

[0192] Alternatively, the pattern area of ​​the mask plate has a single through hole (not shown in the figure), and the mask plate assembly is used to form a common layer in the OLED production process, as the aforementioned CMM mask plate;

[0193] Alternatively, the pattern area of ​​the mask plate has a single through hole (not shown in the figure), and the mask plate assembly is used to form an encapsulation layer in the OLED production process, serving as the aforementioned encapsulation mask plate.

[0194] In one embodiment, when the aforementioned is used as a CMM mask or a packaging mask, the pattern area of ​​the mask may have multiple through holes (not shown in the figure), preferably no more than four, and the multiple through holes are located in the same opening of the mask frame.

[0195] In summary, the manufacturing method provided in the embodiments of the present disclosure, the mask frame obtained by the manufacturing method, and the mask plate assembly including the mask frame have the advantages of high production efficiency, high product precision and effective alleviation of the mask plate sagging phenomenon compared to the prior art.

[0196] The above description is only part of the specific implementation methods of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any changes or substitutions that can be easily thought of by any technician familiar with the technical field within the technical scope disclosed in the embodiments of the present disclosure should be included in the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be based on the protection scope of the claims.

Claims

1. A method for manufacturing a mask frame, characterized in that: include: Providing a substrate, wherein the substrate is in a plate shape and has a first surface and a second surface opposite to each other; forming a first groove, wherein the first groove is formed on the second surface in a depth direction facing the first surface; Forming a support portion, forming a plurality of openings in the first groove that penetrate to the first surface and are arranged in an array to form the support portion; The support portion includes ribs between the openings and a peripheral support portion surrounding the opening array, and the peripheral support portion is located in the first groove.

2. The method according to claim 1, characterized in that: The production method further comprises: forming a second groove, forming a plurality of second grooves at the bottom of the first groove with a depth direction facing the first surface, wherein the plurality of second grooves are arranged in an array; The forming of the support portion further comprises: The plurality of openings are disposed at the bottoms of the plurality of second grooves in a one-to-one correspondence.

3. The method according to claim 2, characterized in that: The production method further comprises: A third groove is formed, and a long strip-shaped third groove is formed between adjacent rows and adjacent columns of the second groove array, respectively. The width of the third groove is smaller than the spacing between adjacent second grooves.

4. The method according to claim 3, characterized in that: The forming of the third grooves includes forming a plurality of spaced third grooves between adjacent rows and adjacent columns of the second groove array.

5. The production method according to any one of claims 1 to 4, characterized in that: The production method further comprises: Forming a fourth groove, forming a plurality of fourth grooves on the first surface with a depth direction facing the second surface, wherein the plurality of fourth grooves are arranged in an array; the fourth grooves are used to fix the mask plate; The forming of the support portion further comprises: The plurality of openings are disposed in the plurality of fourth grooves in a one-to-one correspondence.

6. The method according to claim 5, characterized in that: The production method further comprises: forming a fifth groove, wherein a plurality of fifth grooves are respectively formed at the bottoms of the plurality of fourth grooves, and the area of ​​the fifth grooves is smaller than that of the fourth grooves; The forming of the support portion further comprises: The plurality of openings are disposed in the plurality of fifth grooves in a one-to-one correspondence.

7. The manufacturing method according to claim 6, characterized in that: The forming of the fourth groove further comprises: Forming the fourth groove by turning, milling, honing or grinding; The forming of the fifth groove further comprises: Forming the fifth groove by turning, milling, honing or grinding; The forming of the fourth groove and the forming of the fifth groove are performed before the forming of the first groove, or The forming of the fourth groove and the forming of the fifth groove are performed after the forming of the first groove, and the bottom of the first groove is supported when the fourth groove and the fifth groove are formed.

8. The manufacturing method according to claim 6, characterized in that: The grooves other than the first groove are formed by etching.

9. The manufacturing method according to claim 1, characterized in that: In the forming of the support portion, the method of forming the opening includes: Forming a through hole penetrating the first groove and the first surface by laser cutting; The through hole is modified by etching as follows to obtain the opening: Enlarging the through hole to a preset value; trimming the inner side surface of the through hole into a target shape, wherein the target shape includes a vertical plane or an inclined plane; The through hole is corrected to a preset accuracy.

10. A mask frame, characterized in that: The mask frame is manufactured by the manufacturing method according to any one of claims 1 to 9.

11. A mask plate assembly, characterized in that: include: The mask frame according to claim 10; A plurality of mask plates, each mask plate comprising a pattern area and a joint portion surrounding an edge of the mask plate; The plurality of mask plates are arranged on one side of the first surface of the mask frame, corresponding to the plurality of openings one by one, and the joint portions of the mask plates are joined to the supporting portions of the mask frame.

12. The mask assembly according to claim 11, characterized in that: The mask frame is specifically manufactured by the manufacturing method as claimed in claim 5; At least a portion of the engaging portion is embedded in and engaged with the fourth groove.

13. The mask assembly according to claim 11, characterized in that: The mask plate also includes a transition area between the pattern area and the joint portion; The width S of the transition zone satisfies: 0.25≤h / S≤1.7 Wherein, h is the thickness of the inner edge of the opening of the mask frame.

14. The mask assembly according to claim 13, characterized in that: The width S of the transition zone satisfies: 0.25≤h / S≤1.

5.

15. The mask assembly according to claim 14, characterized in that: The width S of the transition zone satisfies: 0.6≤h / S≤1.

16. The mask assembly according to any one of claims 11 to 15, characterized in that: The pattern area of ​​the mask plate has a plurality of pixel through holes for forming pixels in an OLED production process; or The pattern area of ​​the mask plate has at least one through hole, which is used to form a common layer or a packaging layer in the OLED production process.

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