Back plate, mask plate and electronic device, and manufacturing method thereof

Abstract

The present disclosure provides a backplane, a mask plate and an electronic device, and a manufacturing method thereof, comprising a base substrate; a pad group located on the base substrate, the pad group comprising a plurality of pads spaced apart from each other, at least two of the plurality of pads being arranged along a first direction; a connecting portion located on a side of a layer where the pad group is located away from the base substrate, the maximum size of an orthographic projection of the connecting portion in the first direction being no greater than a size of an orthographic projection of the pad in the first direction; an insulating reflective layer comprising a first hollow structure, the first hollow structure exposing the pad group; and a thickness of the insulating reflective layer in a direction perpendicular to the base substrate being greater than 30 μm.

Description

Technical Field

[0001] The present disclosure relates to the field of display technology, and in particular to a backplane, a mask plate, an electronic device, and a manufacturing method thereof. Background Art

[0002] SMT is the abbreviation of Surface Mounted Technology, which is the most popular technology and process in the electronic assembly industry. It is a technology that places electronic components with pins on the surface of a substrate with pads and assembles them by soldering through reflow soldering or dip soldering. In order to complete the fixed connection between the electronic components and the pads, it is necessary to set solder on the pads on the substrate to be electrically connected to the electronic components, and then go through a series of processes to achieve the fixed connection between the electronic components and the pads. Summary of the invention

[0003] The disclosed embodiments provide a back plate, a mask plate, an electronic device, and a manufacturing method thereof, so as to improve the reflectivity of the back plate and increase the yield of a high-step difference mask.

[0004] A backplane provided in an embodiment of the present disclosure includes:

[0005] substrate substrate;

[0006] A pad group, located on the base substrate, the pad group includes a plurality of pads spaced apart from each other, at least two pads of the plurality of pads are arranged along a first direction;

[0007] A connecting portion is located at a side of the layer where the pad group is located away from the base substrate, and the maximum size of the orthographic projection of the connecting portion in the first direction is not greater than the size of the orthographic projection of the pad in the first direction;

[0008] The insulating reflective layer comprises a first hollow structure, wherein the first hollow structure exposes the pad group; the thickness of the insulating reflective layer in a direction perpendicular to the substrate is greater than 30 μm.

[0009] In some embodiments, in the above-mentioned backplane provided by the embodiments of the present disclosure, the thickness of the insulating reflective layer in a direction perpendicular to the base substrate is greater than or equal to 50 μm and less than or equal to 60 μm.

[0010] In some embodiments, in the above-mentioned backplane provided by the embodiments of the present disclosure, the size of the at least two pads arranged along the first direction in the second direction is smaller than the size of the first hollow structure in the second direction, and the second direction is perpendicular to the first direction.

[0011] In some embodiments, in the above-mentioned backplane provided by the embodiments of the present disclosure, the difference between the size of the first hollow structure in the second direction and the size of the at least two pads arranged along the first direction in the second direction is greater than or equal to 70 μm and less than or equal to 120 μm.

[0012] In some embodiments, in the above-mentioned backplane provided by the embodiments of the present disclosure, the size of the first hollow structure in the first direction is greater than or equal to the size of the at least two pads arranged along the first direction in the first direction.

[0013] In some embodiments, in the above-mentioned backplane provided by the embodiments of the present disclosure, the difference between the size of the first hollow structure in the first direction and the size of the at least two pads arranged along the first direction in the first direction is greater than or equal to 0 μm and less than or equal to 100 μm.

[0014] In some embodiments, in the above-mentioned backplane provided by the embodiments of the present disclosure, the multiple solder pads also include at least two solder pads arranged along the second direction; the size of the first hollow structure in the second direction is greater than or equal to the size of the at least two solder pads arranged along the second direction, and the second direction is perpendicular to the first direction.

[0015] In some embodiments, in the above-mentioned backplane provided by the embodiments of the present disclosure, the size of the orthographic projection of the connecting portion in the second direction is not greater than the size of the orthographic projection of the pad in the second direction.

[0016] In some embodiments, the above-mentioned backplane provided in the embodiments of the present disclosure further includes a solder resist layer located between the base substrate and the insulating reflective layer, the solder resist layer includes a second hollow structure, and the orthographic projection of the second hollow structure on the base substrate coincides with the orthographic projection of the solder pad on the base substrate.

[0017] In some embodiments, in the above-mentioned backplane provided in the embodiments of the present disclosure, the ratio of the thickness of the solder resist layer in a direction perpendicular to the base substrate to the thickness of the pad in a direction perpendicular to the base substrate is greater than or equal to 0.8 and less than or equal to 1.2.

[0018] On the other hand, an embodiment of the present disclosure provides a mask plate, which is configured as a mask of the backplane provided by the embodiment of the present disclosure, and the mask plate includes:

[0019] A body, the body comprising at least one group of hollow structures, each group of the hollow structures comprising at least two of the openings spaced apart from each other;

[0020] A protrusion is located on one side of the main body, and the orthographic projection of the protrusion on the main body is located at least between the openings contained in the same group. The height of the protrusion in a direction perpendicular to the main body is equal to the distance from the surface of the solder resist layer away from the side of the base substrate to the surface of the insulating reflective layer away from the side of the base substrate.

[0021] In some embodiments, in the above-mentioned mask plate provided by the embodiments of the present disclosure, the orthographic projection of the protrusion on the body is only located between the openings contained in the same group.

[0022] In some embodiments, in the above-mentioned mask provided by the embodiments of the present disclosure, the height of the protrusion in a direction perpendicular to the body is greater than or equal to 50 μm and less than or equal to 60 μm.

[0023] In some embodiments, in the mask provided by the embodiments of the present disclosure, in a direction perpendicular to the body, the width of the protrusion in the first direction remains unchanged.

[0024] In some embodiments, in the mask provided by the embodiments of the present disclosure, the ratio of the spacing between two adjacent pads in the first direction to the width of the protrusion in the first direction is greater than or equal to 0.7 and less than or equal to 1.75.

[0025] In some embodiments, in the mask provided by the embodiments of the present disclosure, the ratio of the spacing between two adjacent pads in the first direction to the width of the protrusion in the first direction is greater than or equal to 0.7 and less than or equal to 0.875.

[0026] In some embodiments, in the above-mentioned mask plate provided by the embodiments of the present disclosure, the main body and the protrusion are an integral structure.

[0027] On the other hand, an embodiment of the present disclosure provides an electronic device, comprising: an electronic component, and the above-mentioned backplane provided by an embodiment of the present disclosure; wherein the electronic component is electrically connected to the pad group.

[0028] On the other hand, an embodiment of the present disclosure provides a method of using the above-mentioned mask plate as the above-mentioned backplane mask, comprising:

[0029] Aligning the mask plate and the back plate so that each group of the hollow structures is directly opposite to each group of the pads;

[0030] While controlling the body to contact with the insulating reflective layer, the protrusion is controlled to contact with the solder resist layer;

[0031] Moving a scraper along a specific direction on the mask plate to push the solder into the openings of the hollow structure, so that the solder falls through the openings onto the pads to form solder joints;

[0032] removing the mask plate from the back plate;

[0033] Placing each pin of the electronic component on each soldering point;

[0034] Through the reflow process, each of the solder joints is solidified and shrunk to form the connecting portion, and each pin of the electronic component is electrically connected to each of the solder pads via the connecting portion.

[0035] In some embodiments, in the above method provided by the embodiments of the present disclosure, controlling the contact between the protrusion and the film layer between each of the pads specifically includes: controlling the contact between the protrusion and the solder resist layer.

[0036] The beneficial effects of the present disclosure are as follows:

[0037] The backplane, mask plate and electronic device provided by the embodiment of the present disclosure, and the manufacturing method thereof, include a substrate substrate; a pad group, located on the substrate substrate, the pad group includes a plurality of pads arranged at intervals, and at least two of the plurality of pads are arranged along a first direction; a connecting portion, located on a side of the layer where the pad group is located away from the substrate substrate, and the maximum size of the orthographic projection of the connecting portion in the first direction is not greater than the size of the orthographic projection of the pad in the first direction; an insulating reflective layer, including a first hollow structure, and the first hollow structure exposes the pad group; the thickness of the insulating reflective layer in the direction perpendicular to the substrate substrate is greater than 30μm. In the related art, the thickness of the insulating reflective layer is less than or equal to 30μm. The present disclosure can improve the overall reflectivity of the backplane by increasing the thickness of the insulating reflective layer. The step difference between the insulating reflective layer and the pad increases with the increase of the thickness of the insulating reflective layer, resulting in the risk of short circuit in the connecting portion made by using the flat mask plate mask in the related art; the mask plate with protrusions provided by the present disclosure can effectively avoid short circuit of the connecting portion and increase the yield of the high step difference mask. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 A schematic diagram of a structure of a region where a pad group is located in a backplane provided in an embodiment of the present disclosure;

[0039] Figure 2 A schematic diagram of another structure of a region where a pad group is located in a backplane provided in an embodiment of the present disclosure;

[0040] Figure 3 A schematic diagram of another structure of a region where a pad group is located in a backplane provided in an embodiment of the present disclosure;

[0041] Figure 4 For along Figure 1 , Figure 2 , Figure 3 Cross-section along line I-II;

[0042] Figure 5 A schematic diagram of another structure of a region where a pad group is located in a backplane provided in an embodiment of the present disclosure;

[0043] Figure 6 For along Figure 5 Cross-sectional view along line III-IV;

[0044] Figure 7 A schematic diagram of another structure of a region where a pad group is located in a backplane provided in an embodiment of the present disclosure;

[0045] Figure 8 A schematic diagram of another structure of a region where a pad group is located in a backplane provided in an embodiment of the present disclosure;

[0046] Fig. 9 A schematic diagram of another structure of a region where a pad group is located in a backplane provided in an embodiment of the present disclosure;

[0047] Fig.10 A structural schematic diagram of a region where a group of hollow structures are located in a mask plate provided in an embodiment of the present disclosure;

[0048] Fig.11 For along Fig.10 Sectional view of line V-VI;

[0049] Fig.12 A schematic diagram of the mask plate and the back plate after being aligned and contacted with each other provided by the embodiment of the present disclosure;

[0050] Fig.13 A schematic diagram of the alignment of the mask plate and the back plate provided in an embodiment of the present disclosure;

[0051] Fig.14 A schematic diagram of a mask plate and a back plate in a masking process provided by an embodiment of the present disclosure;

[0052] Fig.15 Another schematic diagram of the mask plate and the back plate in the masking process provided by the embodiment of the present disclosure;

[0053] Fig.16 A schematic diagram of separating a mask plate and a back plate provided in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0054] In order to make the purpose, technical solution and advantages of the embodiment of the present disclosure clearer, the technical solution of the embodiment of the present disclosure will be clearly and completely described below in conjunction with the drawings of the embodiment of the present disclosure. It should be noted that the size and shape of each figure in the drawings do not reflect the actual proportion, and the purpose is only to illustrate the content of the present disclosure. And the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions.

[0055] Unless otherwise defined, the technical or scientific terms used herein shall have the usual meanings understood by persons of ordinary skill in the field to which the present disclosure belongs. The words "first", "second" and similar terms used in the present disclosure specification and claims do not indicate any order, quantity or importance, but are only used to distinguish different components. Words such as "include" or "comprise" mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Inside", "outside", "upper", "lower" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0056] Solder paste welding is widely used in the field of electronic parts assembly due to its good conductivity and high reliability of solder joints. Solder paste welding is an important process in surface mounting technology and can realize the assembly of electronic components. The present disclosure provides a backplane, such as Figures 1 to 4 As shown, including:

[0057] A base substrate 101, on which a connection line and / or circuit may be provided, for providing an electrical signal to each pad 102, thereby driving the electronic components connected to the pad 102 through the connection portion 103;

[0058] A pad group is located on the base substrate 101, the pad group includes a plurality of pads 102 spaced apart from each other, and at least two pads 102 in the pad group are arranged along a first direction X;

[0059] The connecting portion 103 is located on a side of the layer where the pad group is located away from the base substrate 101, and the maximum size S of the orthographic projection of the connecting portion 103 in the first direction X is 31 Not greater than the size S of the orthographic projection of the pad 102 in the first direction X 21 Optionally, the maximum size S of the orthographic projection of the connecting portion 103 in the first direction X 31 The size S of the orthographic projection of the pad 102 in the first direction X 21The ratio is greater than or equal to 0.5 and less than or equal to 1, for example, it can be 0.5, 0.6, 0.7, 0.8, 1, etc.; in some embodiments, the connecting portion 103 is formed by solder, which can be a tin metal or a metal alloy containing tin; in a specific implementation, the solder falls on the pad 102 through the opening of the mask plate, and the solder with a certain fluidity will spread on the pad 102 in an approximately circular or square shape; then the Mini LED is placed on the solder, and then through the reflow process, the solder is solidified and contracted to form the connecting portion 103, so that the Mini LED can be fixed on the pad 102 through the connecting portion 103; the connecting portion 103 is located between the Mini LED pin and the pad 102, and the orthographic projection shape of the connecting portion 103 on the substrate substrate 101 is limited by the orthographic projection shape of the Mini LED pin and the pad 102 on the substrate substrate 101, which is usually the same as the electrically connected Mini LED. The shape of the orthographic projection of the LED pin on the base substrate 101 and the shape of the orthographic projection of the pad 102 on the base substrate 101 are substantially the same, for example, approximately circular or square;

[0060] The insulating reflective layer 104 includes a first hollow structure A, which exposes the pad group; the thickness H of the insulating reflective layer 104 in the direction Z perpendicular to the base substrate 101 is greater than 30 μm; optionally, the insulating reflective layer 104 can be made of a material with high reflectivity, such as white ink.

[0061] In the above-mentioned backplane provided in the embodiment of the present disclosure, by setting the thickness H of the insulating reflective layer 104 to be greater than 30μm, the reflectivity of the insulating reflective layer 104 can be effectively increased compared to the 30μm insulating reflective layer 104 in the related art, so that the loss of light of the Mini LED is reduced, and more light can be reflected to the light-emitting side of the electronic device, which significantly increases the brightness of the electronic device. When the electronic device achieves the same brightness, the insulating reflective layer 104 provided in the embodiment of the present disclosure can increase the light emitted by the MiniLED, so that a smaller current can be used to drive the MiniLED to emit light, thereby reducing the energy consumption of the electronic device. Compared with electronic devices using an insulating reflective layer 104 with a thickness of 30μm or less in the related art, the present disclosure can reduce energy consumption by about 10%.

[0062] Setting solder is an important step in the welding process. It is the process of using a flat mask with a flat surface to transfer solder paste to the pad of the backplane in a quantitative and positioned manner. The size of the pad is basically the same as the size of the electronic component pin. When more precise and smaller electronic components are used, the accuracy requirements for setting the solder process also increase accordingly. Since the flat mask itself has a certain thickness in the direction Z perpendicular to the base substrate 101, and the flat mask is directly placed on the insulating reflective layer 104, the inventors found that if the scraping method is used to ensure that the solder is transferred to the pad 102 in a quantitative and positioned manner, the step difference between the insulating reflective layer 104 and the pad 102 should not exceed a set size, for example, 30 μm; and when the step difference between the insulating reflective layer 104 and the pad 102 is greater than 30 μm, that is, the distance from the flat mask to the pad 102 in the direction Z perpendicular to the base substrate 101 is large, resulting in the movement path of the solder in the direction Z perpendicular to the base substrate 101 being uncontrolled, and thus the uniformity of the solder amount on the pad 102 cannot be guaranteed, and may even cause the solder that should be located on different pads 102 to bridge and short-circuit. In order to solve the above-mentioned problems, the present disclosure provides a mask plate, specifically, the mask plate is thickened to form a protrusion on at least the side where the two opening gaps corresponding to the same pad group are located, so that the movement path of the solder transferred to the pad 102 can be limited, thereby improving the uniformity of the corresponding solder amount on each pad 102; at the same time, the protrusions are used to separate the solder on adjacent pads 102 to avoid solder bridging.

[0063] At the same time, the inventors further considered that there is friction between the solder and the protrusions on the mask plate, and the solder may stick to the protrusions due to the friction, that is, the solder cannot move to the pad as expected or part of the solder is taken away when the mask plate is removed. Therefore, it is necessary to reasonably set the thickness H of the insulating reflective layer 104. In the above-mentioned backplane provided by the embodiment of the present disclosure, in order to take into account the reflectivity of the insulating reflective layer 104 and the smooth demolding of the solder, the thickness H of the insulating reflective layer 104 in the direction Z perpendicular to the base substrate 101 can be greater than or equal to 50μm and less than or equal to 60μm, for example, 50μm, 55μm, 60μm, etc.

[0064] In some embodiments, in the above-mentioned backplane provided in the embodiments of the present disclosure, in order to prevent the protrusions on the mask plate from contacting with the insulating reflective layer 104 and damaging the surface of the insulating reflective layer 104 when the mask plate is placed on the backplane, the edge of the first hollow structure A extending along the first direction X can be at a certain distance from the pad group in the second direction Y, that is, the size S of at least two pads 102 arranged along the first direction X in the second direction Y is 22 Smaller than the dimension S of the first hollow structure A in the second direction Y 41 , the second direction Y is perpendicular to the first direction X, such as Figure 1 and Figure 2Considering the influence of the manufacturing tolerance of the mask plate, the alignment tolerance of the mask plate and the back plate, the manufacturing tolerance of the first hollow structure A, etc., the dimension S of the first hollow structure A in the second direction Y is 41 The size S of at least two pads 102 arranged along the first direction X in the second direction Y is 22 The difference is preferably greater than or equal to 70 μm and less than or equal to 120 μm, for example, it can be 70 μm, 80 μm, 90 μm, 100 μm, 110 μm, 120 μm, etc.

[0065] In some embodiments, to further improve the reflectivity, after the solder is provided, Figure 3 As shown, in the region between the edge of the first hollow structure A extending in the first direction X and the boundary of the pad 102 with the smallest distance therefrom, a reflective structure 104' is added, and the material of the reflective structure 104' can be the same as that of the insulating reflective layer 104. Of course, in some embodiments, the size S of the first hollow structure A in the second direction Y is 41 is substantially equal to the size S of at least two pads 102 arranged along the first direction X in the second direction Y. 22 When the solder is provided, the reflective structure 104' may not be provided. Figure 1 and Figure 2 shown.

[0066] In some embodiments, in the above-mentioned backplane provided in the embodiments of the present disclosure, as Figures 1 to 6 As shown, after the back plate and the mask plate are aligned, there is a protrusion of the mask plate just above the gap of the pad 102 in the first direction X, so that in the first direction X, the distance between the protrusion of the mask plate and the insulating reflective layer 104 is at least equal to the size S of the pad 102 in the first direction X. 21 Therefore, the protrusions can be effectively prevented from contacting or scratching the insulating reflective layer 104 in the first direction X. Based on this, the size S of the first hollow structure A in the first direction X is 42 The size S of at least two pads 102 arranged along the first direction X may be greater than or equal to the size S of at least two pads 102 arranged along the first direction X. 23 To ensure the reflectivity of the insulating reflective layer 104, the dimension S of the first hollow structure A in the first direction X is 42 It should not be too large. Optionally, in the back plate provided in the embodiment of the present disclosure, the size S of the first hollow structure A in the first direction X is 42 The size S of at least two pads 102 arranged along the first direction X in the first direction X is 23 The difference is greater than or equal to 0 μm and less than or equal to 100 μm, for example, it can be 0 μm, 10 μm, 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 110 μm, etc.

[0067] In some embodiments, in the above-mentioned backplane provided in the embodiments of the present disclosure, as Figures 7 to 9 As shown, each pad group includes at least two pads 102 arranged along the first direction X, and may also include at least two pads 102 arranged along the second direction Y; after the back plate and the mask plate are aligned, the protrusion of the mask plate is located directly above the gap between two adjacent pads 102, so that in the second direction Y, the distance between the protrusion of the mask plate and the insulating reflective layer 104 is at least equal to the size S of the pad 102 in the second direction Y. 22 Therefore, the protrusions can be effectively prevented from contacting or scratching the insulating reflective layer 104 in the second direction Y. Based on this, the size S of the first hollow structure A in the second direction Y is 41 The size S of at least two pads 102 arranged along the second direction Y may be greater than or equal to the size S of at least two pads 102 arranged along the second direction Y. 24 , the second direction Y is perpendicular to the first direction X.

[0068] It should be noted that, in the embodiment provided in the present disclosure, the protrusions of the mask plate may correspond to the gaps between the pads 102 included in the pad group. Figures 7 to 9 As shown, in the case where a pad group includes at least two pads 102 arranged along a first direction X, and at least two pads 102 arranged along a second direction Y, the gaps between the pads 102 in a pad group are in the shape of a "cross" or a "well", and accordingly, the orthographic projection of the protrusion on the body can have a "cross" or a "well" structure.

[0069] In some embodiments, in the above-mentioned backplane provided in the embodiments of the present disclosure, as Figures 7 to 9 As shown, the size S of the orthographic projection of the connecting portion 103 in the second direction Y is 32 Not greater than the size S of the positive projection of the pad 102 in the second direction Y 22 Optionally, the size S of the orthographic projection of the connecting portion 103 in the second direction Y is 32 The size S of the orthographic projection of the pad 102 in the second direction Y 22 The ratio is greater than or equal to 0.5 and less than or equal to 1, for example, it can be 0.5, 0.6, 0.7, 0.8, 1, etc.

[0070] In some embodiments, in the above-mentioned backplane provided in the embodiments of the present disclosure, as Figures 1 to 9As shown, a solder resist layer 105 located between the base substrate 101 and the insulating reflective layer 104 may also be included, the solder resist layer 105 includes a plurality of second hollow structures B, and the orthographic projections of the plurality of second hollow structures B on the base substrate 101 are substantially coincident with the orthographic projections of each pad 102 on the base substrate 101, that is, they may be completely coincident, or within the error range caused by factors such as process and measurement. The solder resist layer 105 may prevent solder (such as solder paste) from moving to areas outside the pad 102, and the solder resist layer 105 may also prevent the circuit in the backplane from being oxidized. Optionally, the solder resist layer 105 may be made of a material (such as ink, etc.) resistant to high temperatures (above 250 degrees).

[0071] In some embodiments, in the above-mentioned backplane provided in the embodiments of the present disclosure, as Figure 4 and Figure 6 As shown, the ratio of the thickness h of the solder resist layer 105 in the direction Z perpendicular to the base substrate 101 to the thickness h' of the pad 102 in the direction Z perpendicular to the base substrate 101 can be greater than or equal to 0.8 and less than or equal to 1.2, for example, h / h' is 1, so as to improve the flatness of the subsequent insulating reflective layer 104, so that the insulating reflective layer 104 provides a flat supporting surface for the mask plate, which is conducive to the printing of solder.

[0072] Accordingly, the embodiment of the present disclosure further provides a mask plate, which is configured as a mask of the above-mentioned backplane provided in the embodiment of the present disclosure, such as Figures 10 to 12 As shown, the mask plate includes:

[0073] A body 201, the body 201 includes at least one group of hollow structures, each group of hollow structures includes at least two openings C arranged at intervals from each other, optionally, each opening C in each group of hollow structures corresponds to each pad 102 in each pad group, and to ensure that the solder falls completely on the pad 102, the ratio of the hollow area of ​​the opening C to the area of ​​the orthographic projection of the pad 102 on the substrate 101 can be set to be equal to 0.5 and less than or equal to 1; optionally, the shape of the orthographic projection of the opening C on the body 201 can be a rectangle, a square, a circle, etc.;

[0074] The protrusion 202 is located on one side of the main body 201, and the orthographic projection of the protrusion 202 on the main body 201 is at least located between the openings K contained in the same group. In the direction perpendicular to the main body 201 (equivalent to the direction Z perpendicular to the base substrate 101), the height of the protrusion 202 exceeding the main body 201 is equal to the distance from the surface of the solder resist layer 105 away from the base substrate 101 to the surface of the insulating reflective layer 104 away from the base substrate 101, so that after the mask plate and the back plate are aligned, the protrusion 202 is in contact with the solder resist layer 105 at least between the openings C, and the main body 201 is in contact with the insulating reflective layer 104 on the other sides of the openings C (i.e., the sides other than the protrusion 202).

[0075] By using the mask plate provided by the present invention, the movement path of the solder transferred to the pad 102 can be limited by the protrusion 202, thereby improving the uniformity of the corresponding solder amount on each pad 102; at the same time, the protrusion 202 can be used to separate the solder on adjacent pads 102 to avoid solder bridging, and the solder on the pad 102 is used to form the connecting portion 103.

[0076] Optionally, the mask plate in the present disclosure may be an electroformed steel mesh, and the material may be stainless steel, etc. The solder may be tin (Sn) paste, etc. Specifically, the tin paste is a paste mixture formed by mixing tin powder, flux, and other surfactants, thixotropic agents, etc. In some embodiments, the particle size of the tin powder is greater than or equal to 5 μm and less than or equal to 15 μm, and the viscosity of the tin paste is 254 Pa.s.

[0077] In some embodiments, in the above-mentioned mask provided in the embodiment of the present disclosure, in order to reduce the friction between the solder and the protrusion 202, the orthographic projection of the protrusion 202 on the body 201 can be set to be only located between the openings C contained in the same group, which is equivalent to using the protrusion 202 as the first limiting structure on the gap side between each opening C, and using the insulating reflective layer 104 as the second limiting structure on the other side, and the first limiting structure and the second limiting structure and the pad 102 are mutually surrounded to form a box-shaped structure, thereby realizing the setting of the solder. In some embodiments, if the friction between the protrusion 202 and the solder is small by surface treatment of the protrusion 202, the orthographic projection of the protrusion 202 on the body 201 can be set to surround each opening C, that is, the protrusion 202 is used as a limiting structure around each opening C, so that the protrusion 202 and the pad 102 are mutually surrounded to form a box-shaped structure, thereby realizing the setting of the solder.

[0078] In some embodiments, in the above-mentioned mask provided in the embodiments of the present disclosure, if Figure 1 and Fig.10 As shown, while preventing the protrusion 202 from contacting or scratching the insulating reflective layer 104 in the second direction Y, in order to effectively isolate the solder on the adjacent pad 102, the length L of the protrusion 202 in the second direction Y can be equal to the size S of the pad 102 in the second direction Y. 22 In some embodiments, the dimension S of the pad 102 in the second direction Y is 22 It can be 150 μm, and the length L of the protrusion 202 in the second direction Y is also 150 μm.

[0079] In some embodiments, in the above-mentioned mask provided in the embodiments of the present disclosure, in order to prevent the surface of the protrusion 202 facing the back plate from not contacting the solder resist layer 105 and failing to block the solder on the adjacent pad 102, the height of the protrusion 202 in the direction perpendicular to the body 201 (equivalent to the direction Z perpendicular to the base substrate 101) can be set to be greater than or equal to 50μm and less than or equal to 60μm, and optionally, the height H' of the protrusion 202 in the direction perpendicular to the body 201 is equal to the thickness H of the insulating reflective layer 104. In some embodiments, the thickness H" of the body 201 can be 30μm, then the thickness of the mask where the protrusion 202 is located is equal to the sum of the thickness H" of the body 201 and the height H' of the protrusion 202, which can be greater than or equal to 80μm and less than or equal to 90μm.

[0080] In some embodiments, in the above-mentioned mask provided in the embodiments of the present disclosure, if Fig.12 As shown, in order to ensure that the solder is smoothly demolded, the width W of the protrusion 202 in the first direction X can be made constant in the direction perpendicular to the body 201 (equivalent to the direction Z perpendicular to the base substrate 101), that is, the cross section of the protrusion 202 in the direction perpendicular to the body 201 (equivalent to the direction Z perpendicular to the base substrate 101) is a rectangle. Of course, in some embodiments, the cross section of the protrusion 202 in the direction perpendicular to the body 201 (equivalent to the direction Z perpendicular to the base substrate 101) can also be other shapes, such as a trapezoid, etc., which is not limited here. The present disclosure is described by taking the cross section of the protrusion 202 in the direction perpendicular to the body 201 (equivalent to the direction Z perpendicular to the base substrate 101) as a rectangle as an example.

[0081] In some embodiments, in the above-mentioned mask provided in the embodiments of the present disclosure, if Fig.12 As shown, the ratio of the spacing G between two adjacent pads 102 in the first direction X to the width W of the protrusion 202 in the first direction X can be greater than or equal to 0.7 and less than or equal to 1.75, which can avoid the solder adhesion on the adjacent pads 102 and ensure the amount of solder on the pad 102, so that the pad 102 maintains a good electrical connection with the electronic component through the solder. Optionally, the spacing G between two adjacent pads 102 in the first direction X is 70μm, and the width W of the protrusion 202 is greater than or equal to 40μm and less than or equal to 100μm, for example, the width W of the protrusion 202 is 40μm, 60μm, 70μm, 80μm, 90μm, 100μm.

[0082] It should be noted that, when the ratio of the spacing G between two adjacent pads 102 in the first direction X to the width W of the protrusion 202 is greater than 1 and less than or equal to 1.75, some solder may be printed at the spacing G between two adjacent pads 102. However, during the reflow process, the sporadic solder at the spacing G between two adjacent pads 102 will reflow to the pad 102 nearby due to the effect of the solder resist layer 105, so that the adjacent pads 102 will not be short-circuited by solder. When the ratio of the spacing G between two adjacent pads 102 in the first direction X to the width of the protrusion 202 is greater than or equal to 0.7 and less than or equal to 1, the solder will be fully printed on the pad 102 to ensure that the adjacent pads 102 will not be short-circuited by solder. Considering that the manufacturing accuracy of the mask plate in the related art is 80μm, the ratio of the spacing G between two adjacent pads 102 in the first direction X to the width W of the protrusion 202 in the first direction X should be greater than or equal to 0.7 and less than or equal to 0.875.

[0083] In some embodiments, in the above-mentioned mask provided in the embodiments of the present disclosure, if Fig.10 As shown, the body 201 and the protrusion 202 can be an integrated structure, so as to facilitate the manufacture of the mask plate and effectively prevent the protrusion 202 from falling off abnormally from the body 201 .

[0084] In some embodiments, the mask plate provided by the present disclosure may be used to mask the backplane provided by the present disclosure through the following steps:

[0085] The first step, such as Fig.13 As shown, the mask plate and the back plate are aligned so that each group of hollow structures is arranged opposite to each pad group.

[0086] Step 2: Fig.12 As shown, while controlling the body 201 to contact the insulating reflective layer 104 , the protrusion 202 is controlled to contact the film layer (eg solder resist layer 105 ) between the pads 102 . Optionally, the back plate may be controlled to move upward until the back plate contacts the mask plate.

[0087] Step 3: Fig.14 and Fig.15As shown, the scraper is moved in a specific direction on the mask plate to push the solder 103' into the opening C of the hollow structure, that is, the solder 103' can fall into the pad 102 through the opening C to form a solder joint 103", and under the influence of the limiting effect of the protrusion 202 and the insulating reflective layer 104, and the ratio of the hollow area of ​​the opening C to the area of ​​the positive projection of the pad 102 on the base substrate 101 (for example, greater than or equal to 0.5 and less than or equal to 1), the thickness of the solder joint 103" is less than or equal to the sum of the thickness H" of the body 201 and the thickness H of the insulating reflective layer 103, for example, the sum of the thickness H" of the body 201 and the thickness H of the insulating reflective layer 104 is greater than or equal to 80μm and less than or equal to 90μm, and the thickness of the solder joint 103" can be greater than or equal to 50μm and less than or equal to 70μm.

[0088] Step 4: Fig.16 As shown, the mask plate is removed from the back plate.

[0089] Step 5: electronic components are arranged on the backplane. Optionally, each pin of the electronic component can be placed on each solder joint 103", so that each pin of the electronic component is connected to each pad 102 through the solder joint 103". Here, the two are temporarily connected mainly by the viscosity of the solder.

[0090] Step 6: Reflow soldering process, solidification of solder joint 103" is achieved in a high temperature environment, solder joint 103" forms connection part 103, so that the electronic component and pad 102 are reliably and firmly connected through connection part 103. During the reflow soldering process, the flux and the like volatilize, which will cause the volume of the finally formed connection part 103 to be smaller than the volume of solder joint 103". Specifically, for example, the thickness of connection part 103 in the direction Z perpendicular to substrate 101 is less than the thickness of solder joint 103" in the direction Z perpendicular to substrate 101. For example, the thickness of connection part 103 in the direction Z perpendicular to substrate 101 is about 20% to 50% of the thickness of solder joint 103" in the direction Z perpendicular to substrate 101. For example, the thickness of solder joint 103" in the direction Z perpendicular to substrate 101 is between 50μm and 70μm, and the thickness of connection part 103 in the direction Z perpendicular to substrate 101 is between 15μm and 25μm.

[0091] Based on the same disclosed concept, the embodiment of the present disclosure further provides an electronic device, including: an electronic component, and the above-mentioned backplane provided in the embodiment of the present disclosure; wherein the electronic component is electrically connected to the pad group, and in some embodiments, one electronic component is electrically connected to one pad group. Since the principle of solving the problem by the electronic device is similar to the principle of solving the problem by the above-mentioned backplane, the implementation of the electronic device provided in the embodiment of the present disclosure can refer to the implementation of the above-mentioned backplane provided in the embodiment of the present disclosure, and the repeated parts will not be repeated.

[0092] In some embodiments, the electronic device provided in the embodiments of the present disclosure may be a backlight module or a display device. Optionally, the display device is any product or component with a display function, such as a mobile phone, a tablet computer, a television, a display, a laptop computer, a digital photo frame, a navigator, a smart watch, a fitness wristband, a personal digital assistant, etc. The display device includes but is not limited to: a radio frequency unit, a network module, an audio output & input unit, a sensor, a display unit, a user input unit, an interface unit, a memory, a processor, and a power supply. In addition, it can be understood by those skilled in the art that the above structure does not constitute a limitation on the above display device provided in the embodiments of the present disclosure. In other words, the above display device provided in the embodiments of the present disclosure may include more or fewer of the above components, or a combination of certain components, or different component arrangements.

[0093] Although the present disclosure has described preferred embodiments, it should be understood that those skilled in the art may make various changes and modifications to the embodiments of the present disclosure without departing from the spirit and scope of the embodiments of the present disclosure. Thus, if these modifications and variations of the embodiments of the present disclosure fall within the scope of the claims of the present disclosure and their equivalents, the present disclosure is also intended to include these modifications and variations.

Claims

1. A backplane, characterized in that: include: substrate substrate; A pad group, located on the base substrate, the pad group includes a plurality of pads spaced apart from each other, at least two pads of the plurality of pads are arranged along a first direction; A connecting portion is located at a side of the layer where the pad group is located away from the base substrate, and the maximum size of the orthographic projection of the connecting portion in the first direction is not greater than the size of the orthographic projection of the pad in the first direction; The insulating reflective layer comprises a first hollow structure, wherein the first hollow structure exposes the pad group; the thickness of the insulating reflective layer in a direction perpendicular to the substrate is greater than 30 μm.

2. The back plate according to claim 1, characterized in that: The thickness of the insulating reflective layer in a direction perpendicular to the base substrate is greater than or equal to 50 μm and less than or equal to 60 μm.

3. The back plate according to claim 1 or 2, characterized in that: The size of the at least two pads arranged along the first direction in the second direction is smaller than the size of the first hollow structure in the second direction, and the second direction is perpendicular to the first direction.

4. The back plate according to claim 3, characterized in that: A difference between a size of the first hollow structure in the second direction and a size of the at least two pads arranged along the first direction in the second direction is greater than or equal to 70 μm and less than or equal to 120 μm.

5. The back plate according to claim 1 or 2, characterized in that: The size of the first hollow structure in the first direction is greater than or equal to the size of the at least two pads arranged along the first direction in the first direction.

6. The back plate according to claim 5, characterized in that: A difference between a size of the first hollow structure in the first direction and a size of the at least two pads arranged along the first direction in the first direction is greater than or equal to 0 μm and less than or equal to 100 μm.

7. The back plate according to claim 1 or 2, characterized in that: The multiple pads also include at least two pads arranged along a second direction; a size of the first hollow structure in the second direction is greater than or equal to a size of the at least two pads arranged along the second direction, and the second direction is perpendicular to the first direction.

8. The back plate according to any one of claims 7, characterized in that: A size of an orthographic projection of the connection portion in the second direction is not greater than a size of an orthographic projection of the pad in the second direction.

9. The back plate according to claim 1, 2, 4, 6 or 8, characterized in that: It also includes a solder resist layer located between the base substrate and the insulating reflective layer, the solder resist layer includes a second hollow structure, and the orthographic projection of the second hollow structure on the base substrate coincides with the orthographic projection of the pad on the base substrate.

10. The back plate according to claim 9, characterized in that: A ratio of a thickness of the solder resist layer in a direction perpendicular to the base substrate to a thickness of the pad in a direction perpendicular to the base substrate is greater than or equal to 0.8 and less than or equal to 1.

2.

11. A mask plate configured as a mask of a backplane according to any one of claims 1 to 10, characterized in that: The mask plate comprises: A body, the body comprising at least one group of hollow structures, each group of the hollow structures comprising at least two openings spaced apart from each other; A protrusion is located on one side of the main body, and the orthographic projection of the protrusion on the main body is located at least between the openings contained in the same group. The height of the protrusion in a direction perpendicular to the main body is equal to the distance from the surface of the solder resist layer away from the side of the base substrate to the surface of the insulating reflective layer away from the side of the base substrate.

12. The mask plate according to claim 11, characterized in that: The orthographic projection of the protrusion on the body is only located between the openings contained in the same group.

13. The mask plate according to claim 11 or 12, characterized in that: The height of the protrusion in a direction perpendicular to the body is greater than or equal to 50 μm and less than or equal to 60 μm.

14. The mask plate according to claim 11 or 12, characterized in that: In a direction perpendicular to the body, the width of the protrusion in the first direction remains constant.

15. The mask plate according to claim 14, characterized in that: A ratio of a distance between two adjacent pads in the first direction to a width of the protrusion in the first direction is greater than or equal to 0.7 and less than or equal to 1.

75.

16. The mask plate according to claim 15, characterized in that: The ratio of the distance between two adjacent pads in the first direction to the width of the protrusion in the first direction is greater than or equal to 0.7 and less than or equal to 0.

875.

17. The mask plate according to claim 11, 12, 15 or 16, characterized in that: The body and the protrusion are an integral structure.

18. An electronic device, characterized in that: include: An electronic component and a backplane as claimed in any one of claims 1 to 10; wherein the electronic component is electrically connected to the pad group.

19. A method for manufacturing an electronic device as claimed in claim 18, characterized in that: include: Aligning the mask plate according to any one of claims 11 to 17 with the back plate so that each group of the hollow structures is arranged opposite to each group of the pads; While controlling the body to contact with the insulating reflective layer, the protrusion is controlled to contact with the solder resist layer; Moving a scraper along a specific direction on the mask plate to push the solder into the openings of the hollow structure, so that the solder falls through the openings onto the pads to form solder joints; removing the mask plate from the back plate; Placing each pin of the electronic component on each soldering point; Through the reflow process, each of the solder joints is solidified and shrunk to form the connecting portion, and each pin of the electronic component is electrically connected to each of the solder pads via the connecting portion.

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