CN219042115U

CN219042115U - Screen plate and circuit board assembly

Info

Publication number: CN219042115U
Application number: CN202223192783.7U
Authority: CN
Inventors: 杜媛媛; 王娜; 李娟�
Original assignee: Beijing Co Wheels Technology Co Ltd
Current assignee: Beijing Co Wheels Technology Co Ltd
Priority date: 2022-11-30
Filing date: 2022-11-30
Publication date: 2023-05-16
Anticipated expiration: 2032-11-30

Abstract

The application discloses a otter board and circuit board subassembly. The screen plate is used for printing connection materials on the circuit board and comprises a body part and a shielding part, the body part is provided with a first hollow which is used for corresponding to a first bonding pad of the circuit board, and the first hollow penetrates through the body part along the thickness direction; the shielding part comprises a shielding structure and a first connecting structure, the shielding structure is positioned in the first hollow and used for shielding a via hole of the first bonding pad, and the first connecting structure is connected between the shielding structure and the body part. The screen plate aims at enabling sufficient connecting materials to be arranged between the circuit board and the electronic component.

Description

Screen plate and circuit board assembly

Technical Field

The application belongs to the technical field of electronic manufacturing, and particularly relates to a screen plate and a circuit board assembly.

Background

With the continuous development of technology, the highly concentrated demands of hardware functions are continuously increased, so that the demands of the compactness of the electronic product structure are also continuously increased, and more electronic components and circuit boards are assembled by adopting an SMT (surface Mount technology) technology (Surface Mounted Technology) to improve the compactness of the electronic product pair.

The pads of existing circuit boards are often provided with vias that extend through the circuit board and can be used to vent gases to reduce the likelihood of air bubbles on the connection material when SMT patches are being performed. However, the arrangement of the via hole also makes the connection material easily leak to the other side of the circuit board through the via hole, so that the connection material on the circuit board, which can be used for being connected with the electronic component, is less, the connection effect between the circuit board and the electronic component is poorer, and the connection reliability between the circuit board and the electronic component is reduced.

Disclosure of Invention

The embodiment of the application provides a screen board and a circuit board assembly, which aim to enable a circuit board and an electronic component to have sufficient connecting materials

In a first aspect, an embodiment of the present application provides a screen, where the screen is used for printing connection materials on a circuit board, the screen includes a body portion and a shielding portion, the body portion is provided with a first hollow, the first hollow penetrates through the body portion along a thickness direction, and the first hollow is used for exposing at least part of a first bonding pad of the circuit board; the shielding part comprises a shielding structure and a first connecting structure, the shielding structure is positioned in the first hollow and used for shielding a via hole of the first bonding pad, and the first connecting structure is connected between the shielding structure and the body part.

According to the embodiment of the first aspect of the application, the shielding structures located in the first hollow are multiple, the shielding structures are arranged at intervals, the shielding part further comprises a second connecting structure, and the second connecting structure is connected between the two shielding structures.

According to any of the foregoing embodiments of the first aspect of the present application, the extension path of the at least one second connection structure passes through the center of the first hollow.

According to any one of the foregoing embodiments of the first aspect of the present application, the shielding structures are four, and the four shielding structures are distributed in the first hollow-out array; the second connection structure is two, and two second connection structures all set up through the center of first fretwork, and wherein, connect in the first connection structure and the extending direction of second connection structure of same shielding structure the same.

According to any of the foregoing embodiments of the first aspect of the present application, an orthographic projection area of the shielding structure in the thickness direction is greater than or equal to an orthographic projection area of the via hole in the thickness direction.

According to any of the foregoing embodiments of the first aspect of the present application, a distance between an orthographic projection edge of the shielding structure in the thickness direction and an orthographic projection edge of the via hole in the thickness direction is greater than or equal to 0.1mm.

According to any of the foregoing embodiments of the first aspect of the present application, the orthographic projection shape of the shielding structure in the thickness direction is at least one of polygonal, circular or elliptical.

According to any one of the foregoing embodiments of the first aspect of the present application, an orthographic projection area of the first hollowed-out portion in the thickness direction is smaller than or equal to an orthographic projection area of the first bonding pad in the thickness direction.

According to any one of the foregoing embodiments of the first aspect of the present application, the body portion is further provided with a second hollow, the second hollow penetrates through the body portion along a thickness direction, and the second hollow is used for exposing at least part of the second bonding pad of the circuit board.

In a second aspect, an embodiment of the present application provides a circuit board assembly, where the circuit board assembly includes an electronic component and a circuit board, and the circuit board is provided with a connection material printed by a screen according to any one of the foregoing first aspect, and the circuit board is connected to the electronic component by the connection material.

The screen plate is used for printing connection materials on a circuit board, the screen plate comprises a body portion and a shielding portion, and the body portion can be used for shielding positions of the circuit board, which do not need to be printed with the connection materials. The body part is provided with a first hollow-out which is used for corresponding to the first bonding pad of the circuit board, and the first hollow-out penetrates through the body part along the thickness direction, so that the connecting material can be printed on the first bonding pad of the circuit board at the first hollow-out position. The shielding part comprises a shielding structure and a first connecting structure, the first connecting structure is connected between the shielding structure and the body part, the first connecting part can limit the relative position between the shielding structure and the body part, the shielding structure can be located in the first hollow and used for shielding the through hole of the first bonding pad, when the circuit board is subjected to printing of connecting materials, the connecting materials can be prevented from being printed to the through hole of the first bonding pad by shielding structure, the connecting materials are prevented from leaking to the other surface of the circuit board through the through hole, and the circuit board can be provided with sufficient connecting materials for being connected with electronic components, so that the circuit board and the electronic components have good connecting effect.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments of the present application will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic structural diagram of a circuit board according to some embodiments of the present application;

FIG. 2 is a schematic diagram of the structure of a mesh plate according to some embodiments of the present application;

FIG. 3 is an enlarged view of a portion of area A of FIG. 2;

FIG. 4 is a schematic diagram of a circuit board printed with a connecting material according to some embodiments of the present application;

fig. 5 is a schematic partial connection cross-section of a circuit board and an electronic component according to some embodiments of the present application.

Reference numerals illustrate:

1-a screen plate;

11-a body portion; 111-first hollowing; 112-second hollowing;

12-shielding part; 121-shielding structure; 122-a first connection structure; 123-a second connection structure;

2-a circuit board; 2 a-a first outer surface; 2 b-a second outer surface;

21-a first bonding pad; 211-via holes;

22-second bonding pads;

3-a connecting material; 31-avoidance space; 32-a first flow-through channel; 33-a second flow-through channel;

4-electronic components;

x-thickness direction.

Detailed Description

In order that the above objects, features and advantages of the present disclosure may be more clearly understood, a further description of aspects of the present disclosure will be provided below. It should be noted that, without conflict, the embodiments of the present disclosure and features in the embodiments may be combined with each other.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present disclosure, but the present disclosure may be practiced otherwise than as described herein; it will be apparent that the embodiments in the specification are only some, but not all, embodiments of the disclosure.

It should be noted that in this document, relational terms such as "first" and "second" and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

The directional terms appearing in the following description are all directions shown in the drawings and do not limit the specific structure of the embodiments of the present application. In the description of the present application, it should also be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be directly connected or indirectly connected. The specific meaning of the terms in the present application can be understood as appropriate by one of ordinary skill in the art.

With the continuous development of technology, the highly concentrated demands of hardware functions are continuously increased, so that the demands of the compactness of the electronic product structure are also continuously increased, and more electronic components and circuit boards are assembled by adopting an SMT (surface Mount technology) technology (Surface Mounted Technology) to improve the compactness of the electronic product pair. In the existing SMT chip mounting technology, gas is often generated when an electronic component and a circuit board are welded, for example, gas is generated when soldering flux in a connecting material volatilizes, so that bubbles are often generated in the connecting material, and the assembly reliability between the circuit board and the electronic component is reduced. Therefore, the pads of the existing circuit board are often provided with via holes penetrating the circuit board, and the via holes can be used for exhausting gas so as to reduce the possibility of generating bubbles on the connection material when SMT bonding is performed. However, the applicant researches find that the arrangement of the through holes also makes the connection material easily leak into the through holes and even leak to the other side of the circuit board, so that the connection material on the circuit board for connection with the electronic component is less, the connection effect between the circuit board and the electronic component is poor, and the connection reliability between the circuit board and the electronic component is reduced.

In order to solve the technical problems, the application is provided. For a better understanding of the present application, the following describes the screen board and the circuit board assembly according to the embodiments of the present application in detail with reference to the accompanying drawings.

Fig. 1 is a schematic structural view of a circuit board 2 according to some embodiments of the present application, fig. 2 is a schematic structural view of a screen 1 according to some embodiments of the present application, fig. 3 is a partially enlarged view of a region a in fig. 2, fig. 4 is a schematic structural view of a circuit board 2 printed with a connection material 3 according to some embodiments of the present application, and fig. 5 is a schematic sectional view of a partial connection between the circuit board 2 and an electronic component 4 according to some embodiments of the present application, wherein an X direction is a thickness direction.

As shown in fig. 1, in some embodiments, the circuit board 2 includes a first pad 21, and the connection material 3 may be printed onto the first pad 21 of the circuit board 2 for connecting the circuit board 2 and the electronic component 4. In some embodiments, the connection between the circuit board 2 and the electronic component 4 may be soldering. In some embodiments, the connection material 3 may be a soldering material, for example, the connection material 3 may be a soldering material such as solder paste. In some embodiments, the circuit board 2 has a via hole 211 provided through the circuit board 2 at the first pad 21, the via hole 211 being capable of exhausting gas generated when the circuit board 2 is soldered with the electronic component 4.

As shown in fig. 1 to 4, the embodiment of the present application provides a screen 1, where the screen 1 is used for printing a connection material 3 on a circuit board 2, the screen 1 includes a body portion 11 and a shielding portion 12, the body portion 11 is provided with a first hollow 111, the first hollow 111 is disposed through the body portion 11 along a thickness direction X, and the first hollow 111 is used for exposing at least a portion of a first bonding pad 21 of the circuit board 2; the shielding portion 12 includes a shielding structure 121 and a first connection structure 122, the shielding structure 121 is located in the first hollow 111 and is used for shielding the via hole 211 of the first pad 21, and the first connection structure 122 is connected between the shielding structure 121 and the body portion 11.

The screen 1 provided in the embodiment of the application is used for printing connection materials 3 on a circuit board 2, the screen 1 comprises a body portion 11 and a shielding portion 12, and the body portion 11 can be used for shielding positions of the circuit board 2 where the connection materials 3 do not need to be printed. The body portion 11 is provided with a first hollow 111 for corresponding to the first pad 21 of the circuit board 2, and the first hollow 111 is provided through the body portion 11 in the thickness direction X, so that the connection material 3 can be printed onto the first pad 21 of the circuit board 2 at the first hollow 111. The shielding part 12 comprises a shielding structure 121 and a first connecting structure 122, the first connecting structure 122 is connected between the shielding structure 121 and the body part 11, and the first connecting part can limit the relative position between the shielding structure 121 and the body part 11, so that the shielding structure 121 can be positioned in the first hollowed-out part 111 and used for shielding the through holes 211 of the first bonding pad 21, and when the circuit board 2 is printed with the connecting material 3, the connecting material 3 can be shielded by the shielding structure 121 and is not easy to print to the through holes 211 of the first bonding pad 21, so that the connecting material 3 is not easy to leak to the other surface of the circuit board 2 through the through holes 211, and the circuit board 2 can be provided with sufficient connecting material 3 for being connected with the electronic component 4, so that the circuit board 2 and the electronic component 4 have better connecting effect.

In some embodiments, the specific setting positions of the first hollowed-out portions 111 on the body portion 11 may be set according to the specific setting positions of the first pads 21, and the number of the first hollowed-out portions 111 may be the same as the number of the first pads 21. For example, when the number of the first pads 21 on one of the outer surfaces of the circuit board 2 is plural, the corresponding mesh board 1 may be provided with plural first hollows 111, and the relative positional relationship between the first hollows 111 may be the same as the relative positional relationship between the first pads 21, so that when the mesh board 1 is attached to one of the outer surfaces of the circuit board 2, the first pads 21 on the outer surface can be exposed from the first hollows 111, so as to facilitate printing the connection material 3 onto the first pads 21.

In some embodiments, the specific setting position of the shielding structure 121 in the first hollow 111 may be set according to the specific setting position of the via hole 211 on the first pad 21. In some embodiments, when the screen 1 is attached to the circuit board 2, the orthographic projection of the via hole 211 in the thickness direction X may be located within the orthographic projection of the shielding structure 121 in the thickness direction X, so that the shielding structure 121 can shield the via hole 211 in the thickness direction X.

As shown in fig. 2 to 4, in some embodiments, when the screen 1 is attached to the circuit board 2, the first connection structure 122 connected between the shielding structure 121 and the body portion 11 can also be used for the shielding portion 12 to connect the material 3, so that the printed connection material 3 can form the first flow channel 32 at the shielding portion of the first connection structure 122, so that the gas generated when the circuit board 2 is soldered to the electronic component 4 can be discharged through the first flow channel 32, and the connection reliability between the circuit board 2 and the electronic component 4 is improved.

In some embodiments, the width of the first connection structure 122 may be greater than or equal to 0.2mm, so that after the connection materials 3 are printed, the space between the connection materials 3 on two sides of the first flow channel 32 is greater than or equal to 0.2mm, so that the first flow channel 32 has a sufficient width to exhaust gas, and the efficiency of exhausting gas from the first flow channel 32 is improved.

In some embodiments, the circuit board 2 may have opposite first and second

outer surfaces

2a and 2b in the thickness direction X, and the via hole 211 at the first pad 21 is disposed through the circuit board 2 in the thickness direction X.

In some embodiments, the first bonding pad 21 may be disposed on the first outer surface 2a, the mesh board 1 may be attached to the first outer surface 2a of the circuit board 2, so that the first bonding pad 21 on the first outer surface 2a of the circuit board 2 may be exposed from the first hollow 111 of the mesh board 1, so that the shielding structure 121 may shield the end portion of the via hole 211 near the first outer surface 2a, so that the connection material 3 may not be easily printed into the via hole 211 due to shielding of the shielding structure 121, and also the connection material 3 may not be easily leaked to the second outer surface 2b of the circuit board 2 through the via hole 211.

In other embodiments, the first bonding pad 21 may be disposed on the second outer surface 2b, and the mesh board 1 may be bonded to the second outer surface 2b of the circuit board 2, so that the first bonding pad 21 on the second outer surface 2b of the circuit board 2 may be exposed from the first hollow 111 of the mesh board 1, so that the shielding structure 121 may shield the end portion of the via hole 211 near the second outer surface 2b, so that the connection material 3 may not be easily printed into the via hole 211 due to shielding of the shielding structure 121, and also the connection material 3 may not easily leak to the first outer surface 2a of the circuit board 2 through the via hole 211.

As shown in fig. 2 to fig. 4, in some embodiments, the orthographic projection area of the shielding structure 121 in the thickness direction X may be greater than or equal to the orthographic projection area of the via hole 211 in the thickness direction X, so that an avoidance space 31 can be formed between the printed connection material 3 and the via hole 211, and the avoidance space 31 can enable the connection material 3 not to leak into the via hole 211 easily, thereby improving the connection reliability between the circuit board 2 and the electronic component 4.

In some embodiments, a distance between an orthographic projection edge of the shielding structure 121 in the thickness direction X and an orthographic projection edge of the via hole 211 in the thickness direction X is greater than or equal to 0.1mm. Through setting up the interval that shelters from between orthographic projection edge on thickness direction X of structure 121 and the via hole 211 in thickness direction X is greater than or equal to 0.1mm for can have great dodging space 31 between connecting material 3 and the via hole 211 after the printing, in order to further make connecting material 3 be difficult for leaking into in the via hole 211, improved the connection reliability between circuit board 2 and the electronic components 4.

The orthographic projection shape of the shielding structure 121 in the thickness direction X may be any shape. In some embodiments, the orthographic projection shape of the shielding structure 121 in the thickness direction X is at least one of polygonal, circular, or elliptical.

In some embodiments, the orthographic projection shape of the shielding structure 121 in the thickness direction X may be set according to the orthographic projection shape of the via hole 211 in the thickness direction X. In some embodiments, the orthographic projection shape of the shielding structure 121 in the thickness direction X may be the same as the orthographic projection shape of the via hole 211 in the thickness direction X.

In some embodiments, the orthographic projection area of the first hollowed out portion 111 in the thickness direction X is smaller than or equal to the orthographic projection area of the first pad 21 in the thickness direction X. Through setting up the orthographic projection area of first fretwork 111 in thickness direction X be less than or equal to the orthographic projection area of first pad 21 in thickness direction X for the linking material 3 after the printing is difficult for spilling over first pad 21, has improved linking material 3's availability factor.

In some embodiments, the orthographic projection shape of the first hollowed out portion 111 in the thickness direction X may be set according to the orthographic projection shape of the first pad 21 in the thickness direction X. In some embodiments, the orthographic projection shape of the first hollowed out portion 111 in the thickness direction X may be the same as the orthographic projection shape of the first pad 21 in the thickness direction X.

As shown in fig. 2 to fig. 4, in some embodiments, the shielding structures 121 located in the first hollow 111 are multiple, the shielding structures 121 are arranged at intervals, the shielding portion 12 further includes a second connection structure 123, and the second connection structure 123 is connected between the two shielding structures 121, so that when the screen 1 is attached to the circuit board 2, the second connection structure 123 connected between the two shielding structures 121 can be used for connecting the shielding portion 12 with the material 3, so that the printed connection material 3 can form a second flow channel 33 at the shielding position of the second connection structure 123, and the gas generated when the circuit board 2 is soldered with the electronic component 4 can be discharged to the position of the through hole 211 or the position of the first flow channel 32 through the second flow channel 33, thereby improving the connection reliability between the circuit board 2 and the electronic component 4.

In some embodiments, the width of the second connection structure 123 may be greater than or equal to 0.2mm, so that after the connection material 3 is printed, the space between the connection materials 3 on both sides of the second circulation channel 33 is greater than or equal to 0.2mm, so that the second circulation channel 33 has a sufficient width to exhaust gas, and the efficiency of exhausting gas from the second circulation channel 33 is improved.

In some embodiments, one shielding structure 121 may be connected to only one first connecting structure 122 and one second connecting structure 123, so that when the screen 1 is attached to one of the outer surfaces of the circuit board 2, the shielding portion 12 is not easy to shield the first pad 21 in an excessively large area, so that the first pad 21 can be printed with more sufficient connecting material 3.

In some embodiments, the first connection structure 122 and/or the second connection structure 123 may be formed along a straight line, so that the first circulation channel 32 and/or the second circulation channel 33 formed after printing the connection material 3 has a higher exhaust efficiency.

As shown in fig. 2 to 4, in some embodiments, the extension path of the at least one second connection structure 123 passes through the center of the first hollow 111. By arranging at least one extending path of the second connecting structure 123 passing through the center of the first hollow 111, the second flow channel 33 formed after printing the connecting material 3 can discharge the gas generated near the center of the first bonding pad 21 to the position of the through hole 211 or the position of the first flow channel 32, so that the gas discharge efficiency is improved, and the connection reliability between the circuit board 2 and the electronic component 4 is improved.

As shown in fig. 1, in some embodiments, the number of the via holes 211 at one first bonding pad 21 is four, and the four via holes 211 may be distributed in an array on the first bonding pad 21, so that the via holes 211 can uniformly exhaust the gases at different positions.

As shown in fig. 2 to 4, in some embodiments, the shielding structures 121 are four, and the four shielding structures 121 are distributed in an array in the first hollow 111; the two second connection structures 123 are disposed at the center of the first hollow 111, where the extending directions of the first connection structure 122 and the second connection structure 123 connected to the same shielding structure 121 are the same.

In the present embodiment, four shielding structures 121 can be used to shield the array distribution via holes 211 on the first pad 21, respectively. The two second connection structures 123 are disposed through the center of the first hollow 111, so that the second flow channel 33 formed after printing the connection material 3 can discharge the gas generated near the center of the first bonding pad 21 to the through hole 211 or the first flow channel 32. By arranging the first connection structure 122 and the second connection structure 123 connected to the same shielding structure 121 in the same extending direction, the gas can flow in and be discharged from the through hole 211, the first flow channel 32 and the second flow channel 33 with higher efficiency, so that the gas discharging efficiency is improved, and the connection reliability between the circuit board 2 and the electronic component 4 is improved.

As shown in fig. 1, in some embodiments, the circuit board 2 may further include a second pad 22, where the second pad 22 may be disposed on the first outer surface 2a and/or the second outer surface 2b of the circuit board 2, and the connection material 3 may be printed onto the circuit board 2 at the second pad 22 for connecting the circuit board 2 and the electronic component 4. In some embodiments, the circuit board 2 is not provided with a via 211 at the second pad 22.

As shown in fig. 2 to 4, in some embodiments, the body portion 11 is further provided with a second hollow 112, the second hollow 112 is disposed through the body portion 11 along the thickness direction X, and the second hollow 112 is used to expose at least a portion of the second pad 22 of the circuit board 2, so that the connection material 3 can be printed onto the first pad 21 of the circuit board 2 at the first hollow 111.

In some embodiments, the specific setting positions of the second hollowed-out portions 112 on the body portion 11 may be set according to the specific setting positions of the second pads 22, and the number of the second hollowed-out portions 112 may be the same as the number of the second pads 22. For example, when the second pads 22 on one of the outer surfaces of the circuit board 2 are plural, the corresponding mesh board 1 may be provided with plural second hollowed-out portions 112, and the relative positional relationship between the second hollowed-out portions 112 may be the same as the relative positional relationship between the second pads 22, so that when the mesh board 1 is attached to one of the outer surfaces of the circuit board 2, the second pads 22 on the outer surface can be exposed from the second hollowed-out portions 112, so as to facilitate printing the connection material 3 onto the second pads 22.

In some embodiments, the orthographic projection shape of the second hollow 112 in the thickness direction X may be set according to the orthographic projection shape of the second pad 22 in the thickness direction X. In some embodiments, the orthographic projection shape of the second hollowed-out portion 112 in the thickness direction X may be the same as the orthographic projection shape of the second pad 22 in the thickness direction X.

As shown in fig. 1 to 5, according to some embodiments of the present application, there is further provided a circuit board assembly including an electronic component 4 and a circuit board 2, wherein a connection material 3 printed by the screen 1 as in any of the foregoing embodiments is disposed on the circuit board 2, and the circuit board 2 and the electronic component 4 are connected by the connection material 3. The connection material 3 printed by the screen 1 in any of the foregoing embodiments is not easy to leak into the via hole 211 of the circuit board 2, so that the circuit board 2 and the electronic component 4 have sufficient connection material 3, and the circuit board assembly has good working stability.

In the foregoing, only the specific embodiments of the present application are described, and it will be clearly understood by those skilled in the art that, for convenience and brevity of description, the specific working processes of the systems, modules and units described above may refer to the corresponding processes in the foregoing method embodiments, which are not repeated herein. It should be understood that the scope of the present application is not limited thereto, and any person skilled in the art can easily conceive various equivalent modifications or substitutions within the technical scope of the present application, which are intended to be included in the scope of the present application.

Claims

1. A screen for printing a connection material on a circuit board, comprising:

the body part is provided with a first hollow, the first hollow penetrates through the body part along the thickness direction and is used for exposing at least part of a first bonding pad of the circuit board;

the shielding part comprises a shielding structure and a first connecting structure, the shielding structure is positioned in the first hollow and used for shielding the through hole of the first bonding pad, and the first connecting structure is connected between the shielding structure and the body part.

2. The mesh plate according to claim 1, wherein the shielding structures in the first hollow are a plurality of, the shielding structures are arranged at intervals, and the shielding part further comprises a second connecting structure, and the second connecting structure is connected between the two shielding structures.

3. The mesh panel of claim 2, wherein at least one of the second connection structures passes through a center of the first cutout.

4. The mesh plate according to claim 3, wherein the number of the shielding structures is four, and the four shielding structures are distributed in an array in the first hollow;

the number of the second connecting structures is two, the two second connecting structures are arranged through the center of the first hollowed-out part,

the first connecting structure and the second connecting structure which are connected to the same shielding structure extend in the same direction.

5. The screen of claim 1, wherein an orthographic projection area of the shielding structure in the thickness direction is greater than or equal to an orthographic projection area of the via hole in the thickness direction.

6. The screen panel of claim 5, wherein a spacing between an orthographic projection edge of the shielding structure in the thickness direction and an orthographic projection edge of the via in the thickness direction is greater than or equal to 0.1mm.

7. The mesh sheet according to any one of claims 1 to 6, wherein an orthographic projection shape of the shielding structure in the thickness direction is at least one of a polygon, a circle, or an ellipse.

8. The web of any one of claims 1 to 6, wherein an orthographic projection area of the first hollowed-out portion in the thickness direction is smaller than or equal to an orthographic projection area of the first land portion in the thickness direction.

9. The screen panel of any one of claims 1 to 6, wherein the body portion is further provided with a second hollowed-out portion provided through the body portion in a thickness direction, the second hollowed-out portion being for exposing at least a portion of a second pad of the circuit board.

10. A circuit board assembly, comprising:

an electronic component;

a circuit board provided with a connection material printed by the screen as claimed in any one of claims 1 to 9, the circuit board being connected to the electronic component by the connection material.