PCB structure with optimized electromagnetic compatibility

Abstract

The utility model belongs to the technical field of PCBs (Printed Circuit Board), and provides a PCB structure with optimized electromagnetic compatibility performance, which comprises a substrate which is divided into a bevel edge part and a plane part, the bevel edge part is distributed around the plane part along the circumferential direction, and a plurality of grooves are arranged on the bevel edge part of the substrate; wherein the depth of the groove is smaller than the thickness of the substrate; and the first copper foil layer covers the surface of the substrate, and the first copper foil layer is arranged in the groove in an interference state. According to the utility model, the electromagnetic compatibility of the PCB can be improved, and the situation of edge cracking between the electroplating copper layer and the substrate is reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of PCB, and in particular relates to a PCB structure with optimized electromagnetic compatibility performance. Background Art

[0002] Common PCBs on the market currently usually have through-hole slots that completely penetrate the PCB board, which not only reduces the use space of the PCB board, but also hinders the routing of multi-layer PCBs. In addition, after tin spraying, the edge of the PCB board will deposit an electroplated copper layer on the bevel, and its bonding force with the substrate is poor, causing the electroplated layer to expand due to heat and separate from the original substrate, affecting electromagnetic compatibility. Therefore, a PCB structure with optimized electromagnetic compatibility performance is urgently needed to solve the above problems. Utility Model Content

[0003] The purpose of the utility model is to provide a PCB structure with optimized electromagnetic compatibility performance to solve the above-mentioned problems, improve the electromagnetic compatibility of the PCB board, and reduce the occurrence of edge bursting between the electroplated copper layer and the substrate.

[0004] To achieve the above object, the utility model provides the following solution: a PCB structure with optimized electromagnetic compatibility performance, comprising:

[0005] The substrate is divided into a bevel portion and a plane portion, and the bevel portion is distributed around the plane portion in a circumferential direction, and the substrate is provided with a plurality of grooves in the bevel portion;

[0006] Wherein, the depth of the groove is less than the thickness of the substrate;

[0007] The first copper foil layer covers the surface of the substrate, and the first copper foil layer is arranged in the groove in an interference state.

[0008] Preferably, it also includes:

[0009] The second copper foil layer covers the upper surface of the first copper foil layer.

[0010] Preferably, a plurality of the grooves are formed on the planar portion of the substrate.

[0011] Preferably, the grooves are distributed in an array relative to the surface of the substrate.

[0012] Preferably, the groove is one of a cylindrical and a trapezoidal structure, and a plurality of the grooves arranged on the substrate have the same size.

[0013] Preferably, the length of the beveled portion on the substrate is not less than 18 mm, and the width is not less than 2 mm, and the length of the flat portion on the substrate is not less than 18 mm, and the width is not less than 2 mm.

[0014] Preferably, the inner diameter of the groove gradually decreases along the direction from the surface of the substrate to the inside of the substrate.

[0015] Preferably, the central axes of the plurality of grooves located on the bevel portion of the substrate are perpendicular to the surface of the bevel portion of the substrate.

[0016] Preferably, the thickness of the second copper foil layer is the same as the thickness of the first copper foil layer.

[0017] Compared with the prior art, the utility model has the following advantages and technical effects:

[0018] In the technical solution, grooves are provided on the beveled portion and the plane portion of the substrate, and the depth of the grooves is less than the thickness of the substrate, thereby avoiding the grooves from penetrating the substrate, reducing the space occupied by the substrate, and providing more space for subsequent wiring, etc., which can not only be used for large-area shielding, thereby improving EMI / RFI performance, but also can use the remaining space to partially shield the inner layer devices and network cables, fully realizing the improvement of the electromagnetic compatibility performance of the overall PCB board, and it can be understood that when the depth of the groove is reduced, the overall substrate can be more conveniently pinned through the device, such as the common BGA packaging device, etc., thereby reducing the wiring length and reducing the weight of the overall PCB board;

[0019] At the same time, the technical solution also opens a groove on the bevel portion and is located at the junction between the first copper foil layer and the substrate. When the first copper foil layer covers the surface of the substrate and is embedded in the groove, the first copper foil layer can directly form an anchoring structure that acts on the substrate, so that the overall first copper foil layer and the substrate are tightly connected, and when tin is subsequently sprayed, the first copper foil layer will expand in the groove even under the action of heat, thereby further improving the connection strength between the first copper foil layer and the bevel portion of the substrate, thereby reducing the occurrence of edge bursting between the first copper foil layer and the substrate and improving the bonding ability between the two. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor:

[0021] Figure 1 is a positional relationship diagram between the substrate and the groove;

[0022] Figure 2 is a position relationship diagram between the hypotenuse part and the plane part;

[0023] Figure 3 It is a top view of the hypotenuse part and the plane part;

[0024] Figure 4 is an axonometric view of the base plate;

[0025] Among them, 1, substrate; 101, bevel portion; 102, plane portion; 103, groove; 2, first copper foil layer; 3, second copper foil layer. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0027] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0028] Example: Refer to Figure 1-Figure 4 , a PCB structure with optimized electromagnetic compatibility performance, comprising:

[0029] The substrate 1 is divided into a bevel portion 101 and a plane portion 102, and the bevel portion 101 is distributed around the plane portion 102 along the circumferential direction. The substrate 1 is provided with a plurality of grooves 103 in the bevel portion 101;

[0030] Wherein, the depth of the groove 103 is less than the thickness of the substrate 1;

[0031] The first copper foil layer 2 covers the surface of the substrate 1 , and the first copper foil layer 2 is arranged in the groove 103 in an interference state.

[0032] In the technical solution, a groove 103 is provided on the bevel portion 101 and the plane portion 102 of the substrate 1, and the depth of the groove 103 is less than the thickness of the substrate 1, thereby avoiding the groove 103 from penetrating the substrate 1, reducing the space occupied by the substrate 1, and providing more space for subsequent wiring, etc., which can not only be used for large-area shielding, thereby improving the EMI / RFI performance, but also can use the remaining space to partially shield the inner layer devices and network cables, and fully improve the electromagnetic compatibility performance of the entire PCB board. It can be understood that when the depth of the groove 103 is reduced, the entire substrate 1 can be more conveniently pinned through the device, such as the common BGA packaging device, etc., thereby reducing the wiring length and reducing the weight of the entire PCB board;

[0033] At the same time, the technical solution also opens the groove 103 on the bevel portion 101 and is located at the junction between the first copper foil layer 2 and the substrate 1. When the first copper foil layer 2 covers the surface of the substrate 1 and is embedded in the groove 103, the first copper foil layer 2 can directly form an anchoring structure that acts on the substrate 1, so that the overall first copper foil layer 2 and the substrate 1 are tightly connected, and when tin spraying is subsequently performed, the first copper foil layer 2 will expand in the groove 103 even under the action of heat, thereby further improving the connection strength between the first copper foil layer 2 and the bevel portion 101 of the substrate 1, thereby reducing the occurrence of edge bursting between the first copper foil layer 2 and the substrate 1 and improving the bonding ability between the two.

[0034] Furthermore, it also includes:

[0035] The second copper foil layer 3 covers the upper surface of the first copper foil layer 2 .

[0036] In the present technical solution, the second copper foil layer 3 is electroplated on the upper surface of the first copper foil layer 2, and the first copper foil layer 2 is formed after the substrate 1 is electroplated with the first copper foil layer 2 during use, thereby effectively improving the bonding strength between the first copper foil layer 2 and the second copper foil layer 3, and the second copper foil layer 3 is also embedded in the groove 103, which can effectively avoid the occurrence of edge bursting relative to the bevel portion 101 of the substrate 1 when it expands due to heat, that is, on the basis of reducing edge bursting, the structural integrity and electromagnetic compatibility effect are further improved.

[0037] Furthermore, a plurality of grooves 103 are formed on the planar portion 102 of the substrate 1 .

[0038] Similarly, when a plurality of grooves 103 are formed on the planar portion 102 of the substrate 1, the bonding between the entire substrate 1 and the first copper foil layer 2 and the second copper foil layer 3 is further enhanced, thereby improving the bonding force between the substrate 1 and the first copper foil layer 2 and the second copper foil layer 3.

[0039] Furthermore, the grooves 103 are distributed in an array relative to the surface of the substrate 1 .

[0040] The grooves 103 are arranged in an array on the substrate 1. When the first copper foil layer 2 and the second copper foil layer 3 are combined with the bevel portion 101 and the plane portion 102 on the substrate 1, the bonding strength between the first copper foil layer 2 and the second copper foil layer 3 and the substrate 1 is effectively stabilized by the plurality of grooves 103 evenly distributed in an array, thereby ensuring the integrity of the structure.

[0041] Furthermore, the groove 103 is a cylindrical or trapezoidal structure, and a plurality of grooves 103 arranged on the substrate 1 have the same size.

[0042] Reference Figure 1It can be seen that the length of the groove 103 does not exceed the length of the substrate 1, and at least two grooves 103 are arranged on the same axis, which enhances the bonding strength between the substrate 1 and the first copper foil layer 2, while fully utilizing the structure of the substrate 1 and improving the effect of reducing space occupancy.

[0043] And the depth of the groove 103 is also less than the sum of the thicknesses of the first copper foil layer 2 and the second copper foil layer 3. Specifically, during use, the laser drilling program is directly controlled by software to perform laser drilling on the surface of the substrate 1, and it is ensured that the drilling depth of the groove 103 does not exceed the thickness of the substrate 1, thereby avoiding the opening of a through hole on the substrate 1.

[0044] Furthermore, the length of the bevel portion 101 on the substrate 1 is not less than 18 mm, and the width is not less than 2 mm, and the length of the plane portion 102 on the substrate 1 is not less than 18 mm, and the width is not less than 2 mm.

[0045] Furthermore, the inner diameter of the groove 103 gradually decreases from the direction along the surface of the substrate 1 to the inside of the substrate 1 .

[0046] By designing the size of the groove 103 so that the end close to the bevel portion 101 or the plane portion 102 of the substrate 1 has a larger diameter, and the inner wall end surface away from the surface of the substrate 1 has a smaller diameter,

[0047] Furthermore, the central axes of the plurality of grooves 103 located on the bevel portion 101 of the substrate 1 are perpendicular to the surface of the bevel portion 101 of the substrate 1 .

[0048] Furthermore, the thickness of the second copper foil layer 3 is the same as the thickness of the first copper foil layer 2 .

[0049] The working process of this embodiment is as follows:

[0050] By providing a groove 103 in the bevel portion 101 and the plane portion 102 of the substrate 1, and the depth of the groove 103 is less than the thickness of the substrate 1, the groove 103 is prevented from penetrating the substrate 1, and the space occupied by the substrate 1 is reduced, thereby providing more space for subsequent wiring, etc., which can not only be used for large-area shielding, thereby improving EMI / RFI performance, but also can use the remaining space to partially shield the inner layer devices and network cables, and fully realize the improvement of the electromagnetic compatibility performance of the entire PCB board. It can be understood that when the depth of the groove 103 is reduced, the entire substrate 1 can be more conveniently introduced through the device. The second copper foil layer 3 is electroplated on the upper surface of the first copper foil layer 2, and the first copper foil layer 2 is formed after the substrate 1 is electroplated with the first copper foil layer 2 during use, thereby effectively improving the bonding strength between the first copper foil layer 2 and the second copper foil layer 3, and the second copper foil layer 3 is also embedded in the groove 103, which can effectively avoid the occurrence of edge bursting relative to the bevel portion 101 of the substrate 1 when it is heated and expanded, that is, on the basis of reducing edge bursting, the structural integrity and electromagnetic compatibility effect are improved;

[0051] Furthermore, by opening the grooves 103 on the bevel portion 101 and arranging the grooves 103 in an array on the substrate 1, when the first copper foil layer 2 and the second copper foil layer 3 are combined with the bevel portion 101 and the plane portion 102 on the substrate 1, the bonding strength between the first copper foil layer 2 and the second copper foil layer 3 and the substrate 1 is effectively stabilized by the plurality of grooves 103 uniformly distributed in an array, thereby ensuring the integrity of the structure. When the first copper foil layer 2 covers the surface of the substrate 1 and is embedded in the grooves 103, the first copper foil layer 2 can directly form an anchoring structure acting on the substrate 1, so that the first copper foil layer 2 and the substrate 1 are tightly connected. Moreover, when tin spraying is performed subsequently, the first copper foil layer 2 will expand in the grooves 103 even under the action of heat, thereby making the first copper foil layer 2 The connection strength with the bevel portion 101 of the substrate 1 is further improved, and the length of the groove 103 does not exceed the length of the substrate 1. At least two grooves 103 are arranged on the same axis to enhance the bonding strength between the substrate 1 and the first copper foil layer 2, while achieving full utilization of the structure of the substrate 1 and improving the effect of reducing space occupancy; the depth of the groove 103 is also less than the sum of the thicknesses of the first copper foil layer 2 and the second copper foil layer 3. Specifically, during use, the laser drilling program is directly controlled by software to perform laser drilling on the surface of the substrate 1, and it is ensured that the drilling depth of the groove 103 does not exceed the thickness of the substrate 1, thereby avoiding the opening of a through hole on the substrate 1, reducing the occurrence of edge bursting between the first copper foil layer 2 and the substrate 1, and improving the bonding ability between the two.

[0052] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0053] The embodiments described above are only descriptions of the preferred methods of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should fall within the protection scope determined by the claims of the present invention.

Claims

1. A PCB structure with optimized electromagnetic compatibility performance, characterized in that: include: The substrate (1) is divided into a bevel portion (101) and a plane portion (102), and the bevel portion (101) is distributed around the plane portion (102) in the circumferential direction, and the substrate (1) is provided with a plurality of grooves (103) in the bevel portion (101); Wherein, the depth of the groove (103) is less than the thickness of the substrate (1); A first copper foil layer (2) covers the surface of the substrate (1), and the first copper foil layer (2) is arranged in the groove (103) in an interference state.

2. The PCB structure with optimized electromagnetic compatibility performance according to claim 1, characterized in that: Also includes: The second copper foil layer (3) covers the upper surface of the first copper foil layer (2).

3. The PCB structure with optimized electromagnetic compatibility performance according to claim 1, characterized in that: The flat surface portion (102) of the substrate (1) is provided with a plurality of grooves (103).

4. The PCB structure with optimized electromagnetic compatibility performance according to claim 1, characterized in that: The grooves (103) are distributed in an array relative to the surface of the substrate (1).

5. The PCB structure with optimized electromagnetic compatibility performance according to claim 1, characterized in that: The groove (103) is one of a cylindrical and a trapezoidal structure, and a plurality of the grooves (103) arranged on the substrate (1) have the same size.

6. The PCB structure with optimized electromagnetic compatibility performance according to claim 1, characterized in that: The length of the beveled edge portion (101) on the substrate (1) is not less than 18 mm, and the width is not less than 2 mm, and the length of the flat surface portion (102) on the substrate (1) is not less than 18 mm, and the width is not less than 2 mm.

7. The PCB structure with optimized electromagnetic compatibility performance according to claim 1, characterized in that: The inner diameter of the groove (103) gradually decreases in a direction from the surface of the substrate (1) to the interior of the substrate (1).

8. The PCB structure with optimized electromagnetic compatibility performance according to claim 1, characterized in that: The central axes of the plurality of grooves (103) located on the bevel portion (101) of the substrate (1) are perpendicular to the surface of the bevel portion (101) of the substrate (1).

9. The PCB structure with optimized electromagnetic compatibility performance according to claim 2, characterized in that: The thickness of the second copper foil layer (3) is the same as the thickness of the first copper foil layer (2).

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