PCB and its processing method

Abstract

A PCB and a processing method thereof, the method comprising: processing through holes on at least two PCB sub-boards respectively, the through holes passing through the PCB sub-boards to which they belong and including first-type through holes and second-type through holes; forming solder plate layers on adjacent surfaces of every two adjacent PCB sub-boards respectively, the pads in the solder plate layers corresponding one-to-one with the first-type through holes on the PCB sub-boards to which they belong and realizing electrical connection; performing welding processing on the solder plate layers of the adjacent PCB sub-boards; wherein the first-type through holes are used to form electrical connections between adjacent PCB sub-boards, and the second-type through holes are used to form electrical connections inside and on the surface of the PCB sub-boards to which they belong. The present invention can effectively reduce process complexity and production costs, and combine the various PCB sub-boards through welding processing.

Description

Technical Field

[0001] The present invention relates to the field of communication technology, and in particular to a PCB and a processing method thereof. Background Art

[0002] With the rapid development of network product performance, the backplane channel capacity requirements used in network products are getting higher and higher. In order to meet the backplane channel capacity requirements, if the ordinary single-sided crimping method is used to process the printed circuit board (PCB) as the backplane, not only is it difficult to meet the backplane capacity requirements, but the PCB design layers are getting higher and higher, and the size design is getting larger and larger. At the same time, the increase in the number of layers makes the board thickness increase accordingly, which brings great challenges to the conventional multi-layer PCB processing technology. The main manifestation is that the large size, board thickness, through-hole electroplating capacity, etc. have reached the manufacturer's equipment capacity limit and are difficult to improve.

[0003] In order to process through holes in PCB, the solution adopted in the prior art is to first make PCB sub-boards separately, then press multiple sub-boards into PCB by conventional pressing, and finally form through holes on PCB by mechanical drilling. Among them, PCB sub-board can be a single-layer board, or it can be a multi-layer board formed by pressing after the inner layer circuit pattern is made by ordinary multi-layer board.

[0004] However, in the prior art, as the diameter of the PCB holes becomes smaller and smaller, the number of layers of the PCB after pressing is large and the thickness is large, resulting in a very large aperture ratio, increasing process complexity and production costs, making it difficult to meet user needs. Summary of the invention

[0005] The technical problem solved by the present invention is to provide a PCB and a processing method thereof, which can effectively reduce the process complexity and production cost, and combine various PCB sub-boards through welding processing.

[0006] To solve the above technical problems, an embodiment of the present invention provides a method for processing a printed circuit board (PCB), comprising: processing through holes on at least two PCB sub-boards respectively, wherein the through holes penetrate the PCB sub-boards to which they belong and include first-type through holes and second-type through holes; forming solder plate layers on adjacent surfaces of every two adjacent PCB sub-boards respectively, wherein each solder pad in the solder plate layer corresponds one-to-one to the first-type through holes on the PCB sub-board to which they belong and realizes electrical connection; performing soldering processing on the solder plate layers of the adjacent PCB sub-boards; wherein the first-type through holes are used to form electrical connections between adjacent PCB sub-boards, and the second-type through holes are used to form electrical connections inside and on the surface of the PCB sub-board to which they belong.

[0007] Optionally, there is a gap between the first type through hole and the corresponding pad, and they are connected by a metal wire; and / or, the first type through hole is directly contacted and connected with the corresponding pad.

[0008] Optionally, between adjacent PCB sub-boards, first type through holes for forming electrical connections are offset from each other.

[0009] Optionally, each pad in the pad sublayer is spaced a preset distance from the second type through hole on the corresponding PCB sub-board.

[0010] Optionally, before processing the through holes on at least two PCB sub-boards respectively, the processing method also includes: obtaining multiple PCB single-layer boards; grouping the multiple PCB single-layer boards, and pressing each group of PCB single-layer boards to form at least two PCB sub-boards.

[0011] Optionally, before forming solder plate layers on adjacent surfaces of every two adjacent PCB sub-boards, the processing method also includes: pouring conductive material into at least a portion of the through holes to form interlayer conductive through holes; and / or, performing electroplating on the inner surfaces of at least a portion of the through holes to form interlayer conductive through holes.

[0012] Optionally, before forming a solder plate layer on adjacent surfaces of every two adjacent PCB sub-boards, the processing method further includes: performing solder mask treatment on the PCB sub-boards to form a solder mask protective layer on the surface of the PCB sub-boards.

[0013] Optionally, the material of the solder plate layer is selected from one or more of the following: copper and its alloy materials, aluminum and its alloy materials, titanium and its alloy materials, platinum and its alloy materials, silver and its alloy materials, gold and its alloy materials.

[0014] Optionally, performing soldering processing on the solder plate layers of the adjacent PCB sub-boards includes: using flux to perform soldering processing on the solder plate layers of the adjacent PCB sub-boards; wherein the material of the flux is selected from: tin and its alloy materials.

[0015] To solve the above technical problems, an embodiment of the present invention provides a printed circuit board PCB, comprising: at least two PCB sub-boards; through holes, respectively located on the at least two PCB sub-boards, penetrating the PCB sub-boards to which they belong, and comprising first-type through holes and second-type through holes; a soldering plate layer, located on adjacent surfaces of every two adjacent PCB sub-boards, wherein each solder pad in the soldering plate layer corresponds to the first-type through hole on the PCB sub-board to which they belong and realizes electrical connection, and each solder pad in the soldering plate layer is spaced from the second-type through hole on the PCB sub-board to which they belong by a preset distance; wherein the PCB is formed by soldering the soldering plates of adjacent PCB sub-boards; the first-type through holes are used to form electrical connections between adjacent PCB sub-boards, and the second-type through holes are used to form electrical connections inside and on the surface of the PCB sub-board to which they belong.

[0016] Optionally, the PCB includes: there is a gap between the first type of through hole and the corresponding pad, and they are connected by a metal wire; and / or the first type of through hole is directly contacted and connected with the corresponding pad.

[0017] Optionally, the PCB includes: first type through holes for forming electrical connections between adjacent PCB sub-boards are offset from each other.

[0018] Compared with the prior art, the technical solution of the embodiment of the present invention has the following beneficial effects:

[0019] In the embodiment of the present invention, by processing through holes on the PCB sub-boards respectively, it is equivalent to drilling holes on a PCB with a smaller thickness, and has a smaller aperture ratio. Compared with drilling holes on a PCB with a large number of layers and a larger thickness after pressing in the prior art, the solution of the embodiment of the present invention can have a smaller aperture ratio, effectively reducing the process complexity and production cost; and by forming solder plate layers on the adjacent surfaces of every two adjacent PCB sub-boards, the various PCB sub-boards can be combined through welding processing.

[0020] Furthermore, there is a gap between the first type of through hole and the corresponding pad, and they are connected by a metal wire. Compared with obtaining a PCB by pressing, in an embodiment of the present invention, each PCB sub-board is combined by welding, and the position of the through hole can be set more flexibly.

[0021] Furthermore, each pad in the solder plate layer is spaced a preset distance from the second type of through-hole on the PCB sub-board to which it belongs, which is equivalent to forming a safe area between the solder pad and the second type of through-hole, thereby effectively avoiding the formation of electrical connection between adjacent PCB sub-boards via the second type of through-hole, which may cause a circuit short circuit in the device.

[0022] Furthermore, the PCB sub-board is formed by grouping the multiple PCB single-layer boards and laminating each group of PCB single-layer boards, so that according to actual needs, an appropriate number of layers can be selected for lamination, and then the pressed PCB sub-boards are welded and assembled, thereby avoiding a decrease in production efficiency due to an excessive number of welding sub-layers, and avoiding an excessively large aperture ratio due to an excessive thickness of the PCB sub-board, thereby achieving a balance between fewer welding times and smaller aperture ratio requirements.

[0023] Furthermore, the PCB sub-board is subjected to solder mask treatment to form a solder mask protective layer on the surface of the PCB sub-board, which can further prevent electrical connection between adjacent PCB sub-boards via the second type of through-holes, thereby preventing a circuit short circuit from occurring in the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of a cross-sectional structure of a PCB in the prior art;

[0025] Figure 2 It is a top view of a PCB in the prior art;

[0026] Figure 3 is a flow chart of a PCB processing method according to an embodiment of the present invention;

[0027] Figures 4 to 5 It is a schematic cross-sectional structure diagram corresponding to each step in a PCB processing method according to an embodiment of the present invention;

[0028] Figure 6 to Figure 7 It is a schematic cross-sectional structure diagram corresponding to each step in another PCB processing method according to an embodiment of the present invention;

[0029] Figure 8 It is a schematic diagram of the cross-sectional structure of another PCB in an embodiment of the present invention. DETAILED DESCRIPTION

[0030] In the prior art, as the diameter of the holes in the PCB becomes smaller and smaller, the number of layers of the PCB after pressing is large and the thickness is large, resulting in a very large aperture ratio, increasing process complexity and production costs, making it difficult to meet user needs.

[0031] Combined with reference Figure 1 and Figure 2 , Figure 1 It is a schematic diagram of a cross-sectional structure of a PCB in the prior art. Figure 2 It is a top view of a PCB in the prior art.

[0032] Specifically, Figure 1 The PCB 100 shown has a thickness of D, and a through hole 110 is processed on the PCB 100, and the diameter of the through hole 110 is d.

[0033] It can be understood that as D becomes larger and d becomes smaller, the ratio of D to d (ie, the aperture ratio) also becomes larger.

[0034] Since in the PCB 100 , it is necessary to reserve enough space between the through holes 110 to form the metal wires 120 , the distance between the through holes 110 needs to be limited, for example, by using a spacing parameter (Pitch) to limit it. Pitch is used to represent the minimum distance between adjacent through holes 110 .

[0035] As a non-limiting example, the thickness D of the PCB 100 is 5 mm, and the pitch is 0.3 mm. The through hole 110 can be used to make the solder ball routing of the chip, so as to connect the corresponding functional pins of the chip to other connection points.

[0036] As can be seen from the above, the diameter of the through hole 120 is about 0.1 mm. If it is too large, it will easily cause a short circuit between the metal wire 120 and the through hole 110. Figure 2 Shown as the dotted ellipse in .

[0037] The aperture ratio calculated based on the diameter of the through hole 120 is 5 / 0.1=50. However, due to the limitation of process capability, the sample factory cannot produce a PCB with a thickness of 5 mm and an aperture ratio of 50.

[0038] In a specific implementation, in order to achieve a thickness of 5 mm and an aperture ratio of 50, a high density interconnect (HDI) PCB may be used, that is, a circuit board with a relatively high line distribution density based on micro blind buried via technology.

[0039] The inventor of the present invention has found through research that when an HDI PCB is used, the alignment is easily offset when the PCB is pressed together many times, resulting in signal disconnection and short circuit. Therefore, some PCBs cannot be designed using HDI.

[0040] In the embodiment of the present invention, by processing through holes on the PCB sub-boards respectively, it is equivalent to drilling holes on a PCB with a smaller thickness, and has a smaller aperture ratio. Compared with drilling holes on a PCB with a large number of layers and a larger thickness after pressing in the prior art, the solution of the embodiment of the present invention can have a smaller aperture ratio, effectively reducing the process complexity and production cost; and by forming solder plate layers on the adjacent surfaces of every two adjacent PCB sub-boards, the various PCB sub-boards can be combined through welding processing.

[0041] In order to make the above-mentioned objects, features and beneficial effects of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0042] Reference Figure 3 , Figure 3 1 is a flow chart of a PCB processing method according to an embodiment of the present invention. The PCB processing method may include steps S31 to S33:

[0043] Step S31: processing through holes on at least two PCB sub-boards respectively, wherein the through holes penetrate the corresponding PCB sub-boards and include first-type through holes and second-type through holes;

[0044] Step S32: forming solder plate layers on adjacent surfaces of every two adjacent PCB sub-boards, respectively, wherein each solder pad in the solder plate layer corresponds one-to-one with the first type through hole on the corresponding PCB sub-board and realizes electrical connection;

[0045] Step S33: performing welding processing on the solder plate layer of the adjacent PCB sub-boards.

[0046] The first type of through holes are used to form electrical connections between adjacent PCB sub-boards, and the second type of through holes are used to form electrical connections inside and on the surface of the corresponding PCB sub-boards.

[0047] Combine the following Figures 4 to 8 Each of the above steps is described below.

[0048] Figures 4 to 5 It is a schematic cross-sectional structure diagram corresponding to each step in a PCB processing method in an embodiment of the present invention.

[0049] like Figure 4 As shown, through hole 211 and through hole 221 are processed on PCB sub-board 201 , and through hole 212 and through hole 222 are processed on PCB sub-board 202 .

[0050] It should be pointed out that in Figure 4 In the method shown in the subsequent figures, two PCB sub-boards are used as an example for explanation, but this is not considered as a limitation on the number of PCB sub-boards.

[0051] Among them, each through hole passes through the PCB sub-board 201 (202) to which it belongs, and includes a first type through hole 211 (212) and a second type through hole 221 (222), wherein the first type through hole 211 (212) is used to form an electrical connection between adjacent PCB sub-boards, and the second type through hole 221 (222) is used to form an electrical connection inside and on the surface of the PCB sub-board 201 (202) to which it belongs.

[0052] Among them, the electrical connection may include direct connection or indirect coupling. In other words, different PCB sub-boards need to be directly connected or indirectly coupled through the first type of through-holes to achieve current conduction between different PCB sub-boards; and the second type of through-holes are not used to electrically connect different PCB sub-boards, but are used for electrical connections inside and on the surface of a single PCB sub-board, such as arranging circuit routing.

[0053] It should be pointed out that the thickness of each PCB sub-board is smaller than the pressed PCB. Therefore, processing through holes on the PCB sub-boards separately is equivalent to drilling holes on a PCB with a smaller thickness, which has a smaller aperture ratio and can effectively reduce process complexity and production costs.

[0054] Furthermore, between adjacent PCB sub-boards, the first type through holes for forming electrical connections may be offset from each other.

[0055] As shown in the figure, the first type through hole 211 and the first type through hole 212 can be offset from each other, for example, offset from each other within a preset offset distance. In other words, the first type through hole 211 and the first type through hole 212 do not need to be strictly aligned, but can be staggered from each other within a preset offset distance.

[0056] Specifically, compared to obtaining a PCB by pressing, in which the through holes of the pressed PCB sub-boards must be aligned, in the embodiment of the present invention, the positions of the through holes can be offset from each other, which is more flexible.

[0057] Reference Figure 5 PCB sub-board 201 and PCB sub-board 202 are adjacent PCB sub-boards, the lower surface of PCB sub-board 201 and the upper surface of PCB sub-board 202 are adjacent surfaces, a pad sub-layer 231 is formed on the lower surface of PCB sub-board 201, and a solder sub-layer 232 is formed on the upper surface of PCB sub-board 202, each pad in the solder sub-layer 231 corresponds one-to-one with the first type through hole 211 on the PCB sub-board 201 to which it belongs and is electrically connected, and each pad in the solder sub-layer 232 corresponds one-to-one with the first type through hole 212 on the PCB sub-board 202 to which it belongs and is electrically connected.

[0058] It should be pointed out that in Figure 4 And the electrical connection between the pad and the first type of through hole shown in the subsequent figures means that when the first type of through hole is filled with conductive material, the pad can be electrically connected to the conductive material, or, when the inner surface of the first type of through hole is electroplated, the pad can be electrically connected to the electroplated layer.

[0059] The pads may be contactable points generated on the surface through a process, which are equivalent to the pins of the chip, similar to the Land Grid Array (LGA) package.

[0060] In the embodiment of the present invention, the size of the pad may be larger than the size of the through hole, thereby reducing the difficulty of the pad docking process.

[0061] Further, the first type through hole 211 may be directly connected to the corresponding pad in the solder sublayer 231 , and the first type through hole 212 may be directly connected to the corresponding pad in the solder sublayer 232 .

[0062] Specifically, electrical connection can be achieved through direct contact connection when conductive material is poured into the first type through hole 211 (212), or when the inner surface of the first type through hole 211 (212) is electroplated.

[0063] Furthermore, the material of the solder plate layer 231 (232) can be selected from one or more of the following: copper and its alloy materials, aluminum and its alloy materials, titanium and its alloy materials, platinum and its alloy materials, silver and its alloy materials, gold and its alloy materials.

[0064] In the processing method of the embodiment of the present invention, the soldering plate layer of the adjacent PCB sub-board may also be soldered.

[0065] Further, the step of soldering the solder sublayers of the adjacent PCB sub-boards may include: using flux 241 to solder the solder sublayer 231 of the adjacent PCB sub-board 201 and the solder sublayer 232 of the PCB sub-board 202 .

[0066] The material of the soldering flux 241 may be selected from: tin and its alloy materials, which is conducive to achieving effective electrical connection.

[0067] In the embodiment of the present invention, by processing the through holes 211 (212) on the PCB sub-boards 201 (202), it is equivalent to drilling holes on a PCB with a smaller thickness, which has a smaller aperture ratio. Compared with drilling holes on a PCB with a large number of layers and a larger thickness after pressing in the prior art, the solution of the embodiment of the present invention can have a smaller aperture ratio, effectively reducing the process complexity and production cost; and by forming solder plate layers on the adjacent surfaces of every two adjacent PCB sub-boards, the various PCB sub-boards can be combined through welding processing.

[0068] Figure 6 to Figure 7 It is a schematic cross-sectional structure diagram corresponding to each step in another PCB processing method in an embodiment of the present invention.

[0069] Reference Figure 6 , through holes 311 and through holes 321 are processed on PCB sub-board 301 , and through holes 312 and through holes 322 are processed on PCB sub-board 302 .

[0070] Each through hole passes through the corresponding PCB sub-board 301 (302), and includes a first type through hole 311 (312) and a second type through hole 321 (322).

[0071] Furthermore, between adjacent PCB sub-boards, the first type through holes for forming electrical connections may be offset from each other.

[0072] As shown in the figure, the first type through hole 311 and the first type through hole 312 can be offset from each other, for example, offset from each other within a preset offset distance. In other words, the first type through hole 311 and the first type through hole 312 do not have to be strictly aligned, but can be staggered from each other within a preset offset distance. Therefore, in the embodiment of the present invention, the positions of the through holes can be offset from each other, which is more flexible.

[0073] Compared to Figure 4 The first type through hole 211 and the first type through hole 212 are shown. Figure 6 The offset between the first type via 311 and the first type via 312 is larger.

[0074] Reference Figure 7 PCB sub-board 301 and PCB sub-board 302 are adjacent PCB sub-boards, the lower surface of PCB sub-board 301 and the upper surface of PCB sub-board 302 are adjacent surfaces, a solder plate layer 331 is formed on the lower surface of PCB sub-board 301, and a solder plate layer 332 is formed on the upper surface of PCB sub-board 302, each solder pad in the solder plate layer 331 corresponds one-to-one with the first type through hole 311 on the PCB sub-board 301 to which it belongs and is electrically connected, and each solder pad in the solder plate layer 332 corresponds one-to-one with the first type through hole 312 on the PCB sub-board 302 to which it belongs and is electrically connected.

[0075] Furthermore, there is a gap between the first type through hole and the corresponding pad, and they are connected by a metal wire.

[0076] Specifically, there is a gap between the first type through hole 311 and the pad in the solder sublayer 331 , and the electrical connection with the first type through hole 312 cannot be achieved directly through the solder sublayer 331 , so the electrical connection can be achieved through the metal wire 351 .

[0077] The metal wire 351 may be embedded in the PCB sub-board 301 , or may be formed on the surface of the PCB sub-board 301 . The embodiment of the present invention does not limit the specific formation method of the metal wire 351 .

[0078] Furthermore, the material of the metal wire 351 can be selected from one or more of the following: copper and its alloy materials, aluminum and its alloy materials, titanium and its alloy materials, platinum and its alloy materials, silver and its alloy materials, gold and its alloy materials.

[0079] In an embodiment of the present invention, there is a gap between the first type of through hole and the corresponding pad, and they are connected by a metal wire. Compared with obtaining a PCB by pressing, in an embodiment of the present invention, each PCB sub-board is combined by welding, and the position of the through hole can be set more flexibly.

[0080] Furthermore, each pad in the pad sublayer is spaced apart from the second type through hole on the corresponding PCB sub-board by a preset distance.

[0081] Specifically, taking the solder plate layer 332 as an example, each solder pad in the solder plate layer 332 is spaced apart from the second type through hole 322 on the corresponding PCB sub-board 302 by a preset distance a.

[0082] Among them, the preset distance a can be determined based on the contour area of ​​the second type through hole 322. The contour area of ​​the second type through hole 322 can be the area where the second type through hole 322 is located, or it can be a larger area obtained by adding a fixed or non-fixed width around the second type through hole 322.

[0083] In an embodiment of the present invention, each pad in the pad sublayer is spaced apart from the second type of through-hole on the PCB sub-board to which it belongs by a preset distance, which is equivalent to forming a safety area between the pad and the second type of through-hole, thereby effectively avoiding the formation of electrical connection between adjacent PCB sub-boards via the second type of through-hole, resulting in a circuit short circuit in the device.

[0084] In the processing method of the embodiment of the present invention, the soldering plate layer of the adjacent PCB sub-board may also be soldered.

[0085] Furthermore, the step of soldering the solder sublayers of the adjacent PCB sub-boards may include: using flux 341 to solder the solder sublayer 331 of the adjacent PCB sub-board 301 and the solder sublayer 332 of the PCB sub-board 302; wherein the material of the flux 341 is selected from: tin and its alloy materials.

[0086] In the embodiment of the present invention, by processing the through holes 311 (312) on the PCB sub-board 301 (302) respectively, it is equivalent to drilling holes on a PCB with a smaller thickness, which has a smaller aperture ratio and effectively reduces the process complexity and production cost; and a safety area is formed between the pad and the second type of through hole, which effectively avoids circuit short circuits in the device.

[0087] related Figure 6 to Figure 7 For more principles, specific implementations and beneficial effects, please refer to the previous article and Figures 4 to 5 The related description about the PCB processing method is not repeated here.

[0088] In a specific implementation of the embodiment of the present invention, before respectively processing through holes on at least two PCB sub-boards, the PCB processing method may also include: obtaining multiple PCB single-layer boards; grouping the multiple PCB single-layer boards, and pressing each group of PCB single-layer boards to form at least two of the PCB sub-boards.

[0089] Reference Figure 8 , Figure 8 It is a schematic diagram of the cross-sectional structure of another PCB in an embodiment of the present invention.

[0090] like Figure 8 The PCB sub-boards 401 (402) shown are obtained by laminating each group of PCB single-layer boards.

[0091] In which, the PCB sub-board 401 and the PCB sub-board 402 are both described as having a 6-layer structure. However, in the embodiment of the present invention, there is no specific restriction on the number of PCB single-layer boards in the PCB sub-board 401 (402), and the number of PCB single-layer boards in the PCB sub-board 401 can be different from that in the PCB sub-board 402, and the thickness of the PCB sub-board 401 can be different from that of the PCB sub-board 402.

[0092] As a non-limiting example, the thickness of PCB sub-board 401 may be 2.5 mm, and the thickness of PCB sub-board 402 may be 2.5 mm, then the aperture ratio is 2.5 / 0.1=25, which can meet the process production requirements of the sample factory.

[0093] As another non-limiting example, the thickness of PCB sub-board 401 may be 2.4 mm, the thickness of PCB sub-board 402 may be 2.4 mm, and a reserved intermediate joint thickness of 0.2 mm is provided. Then, the aperture ratio is 2.4 / 0.1=24, which can meet the process production requirements of the sample factory.

[0094] In the embodiment of the present invention, the PCB sub-board is formed by grouping the multiple PCB single-layer boards and pressing each group of PCB single-layer boards, so that according to actual needs, an appropriate number of layers can be selected for pressing, and then the pressed PCB sub-boards are welded and assembled, thereby avoiding a decrease in production efficiency due to an excessive number of welding sub-layers and avoiding an excessively large aperture ratio due to an excessive thickness of the PCB sub-board, and achieving a balance between fewer welding times and smaller aperture ratio requirements.

[0095] Then, a device 461 (such as a chip) can be placed on the upper surface of the PCB sub-board 401 to form an inner layer routing (fanout) on the inner layer of the PCB sub-board 401, and a device 462 (such as a chip) can be placed on the lower surface of the PCB sub-board 402 to form an inner layer routing on the inner layer of the PCB sub-board 402.

[0096] Specifically, through holes 411 and 421 can be processed on PCB sub-board 401, and through holes 412 and 422 can be processed on PCB sub-board 402. Each through hole passes through the PCB sub-board 401 (402) to which it belongs, and includes a first type of through hole 411 (412) and a second type of through hole 421 (422). A solder plate layer 431 is formed on the lower surface of PCB sub-board 401, and a solder plate layer 432 is formed on the upper surface of PCB sub-board 402.

[0097] Among them, each solder pad in the solder sublayer 431 corresponds one-to-one with the first type through hole 411 on the corresponding PCB sub-board 401 and realizes electrical connection, and each solder pad in the solder sublayer 432 corresponds one-to-one with the first type through hole 412 on the corresponding PCB sub-board 402 and realizes electrical connection.

[0098] like Figure 8 As shown, the second type through hole 421 is used to form an electrical connection inside and on the surface of the PCB sub-board 401, and the second type through hole 422 is used to form an electrical connection inside the PCB sub-board 402. Specifically, the second type through hole 421 (422) is not used to electrically connect different PCB sub-boards, but is used for electrical connection inside and on the surface of a single PCB sub-board, such as arranging circuit traces.

[0099] Furthermore, there is a gap between the first type through hole 411 and the pad in the solder sublayer 431 , and the electrical connection with the first type through hole 412 cannot be achieved directly through the solder sublayer 431 , so the electrical connection can be achieved through the metal wire 451 .

[0100] Further, conductive material is poured into at least a portion of the through holes to form interlayer conductive through holes, and / or electroplating is performed on inner surfaces of at least a portion of the through holes to form interlayer conductive through holes.

[0101] Specifically, Figure 8 In the processing method shown, interlayer conductive vias can be formed by pouring conductive material into the through holes, and the interlayer conductive vias are sealed structures at this time. In another processing method, interlayer conductive vias can also be formed by electroplating the inner surface of the through holes, and the interlayer conductive vias are hollow structures at this time, thereby meeting specific needs in different working scenarios.

[0102] Furthermore, the conductive material may be selected from one or more of the following: copper and its alloy materials, aluminum and its alloy materials, titanium and its alloy materials, platinum and its alloy materials, silver and its alloy materials, gold and its alloy materials.

[0103] In a specific implementation of the embodiment of the present invention, the method may further include: performing solder resist treatment on the PCB sub-board to form a solder resist protective layer (not shown) on the surface of the PCB sub-board.

[0104] Specifically, a solder mask process may be a step of applying solder mask on the surface of a PCB.

[0105] Among them, the step of performing solder mask treatment on the PCB sub-board can be performed before forming the solder plate layer, can also be performed after the step of processing the through hole, and can also be performed after the step of forming the interlayer conductive through hole.

[0106] It should be pointed out that for a PCB sub-board that has not been subjected to solder mask treatment, there may be a situation where the pads in the solder sub-layer 431 are too close to the second type of through-hole 422, resulting in electrical connection, or there may be a situation where the pads in the solder sub-layer 432 are too close to the second type of through-hole 421, resulting in electrical connection, and in severe cases, a circuit short circuit may occur.

[0107] In an embodiment of the present invention, the PCB sub-board 401 (402) is subjected to solder mask treatment to form a solder mask protective layer on the surface of the PCB sub-board 401 (402), which can further prevent electrical connection between adjacent PCB sub-boards via the second type of through-holes, thereby preventing a circuit short circuit from occurring in the device.

[0108] Then, a solder sublayer 431 is formed on the lower surface of the PCB sub-board 401, and a solder sublayer 432 is formed on the upper surface of the PCB sub-board 402. Then, a flux 441 can be used to perform a soldering process on the solder sublayer 431 of the adjacent PCB sub-board 401 and the solder sublayer 432 of the PCB sub-board 402; wherein the material of the flux 441 is selected from: tin and its alloy materials.

[0109] In an embodiment of the present invention, a PCB is also disclosed, referring to Figure 5, may include: at least two PCB sub-boards 201 (202); through holes 211 (212, 221, 222), respectively located on the at least two PCB sub-boards 201 (202), penetrating the corresponding PCB sub-boards 201 (202), and including first-type through holes 211 (212) and second-type through holes 221 (222); a solder plate layer 231 (232), located on adjacent surfaces of every two adjacent PCB sub-boards 201 (202), wherein each solder pad in the solder plate layer 231 (232) is connected to the first-type through holes 211 (212) on the corresponding PCB sub-board 201 (202). ) correspond one to one and realize electrical connection, each pad in the solder plate layer 231 (232) is spaced a preset distance from the second type through hole 221 (222) on the corresponding PCB sub-board 201 (202); wherein the PCB is formed by soldering the solder plate layers 231 (232) of adjacent PCB sub-boards 201 (202); the first type through hole 211 (212) is used to form an electrical connection between adjacent PCB sub-boards 201 (202), and the second type through hole 221 (222) is used to form an electrical connection inside and on the surface of the corresponding PCB sub-board 201 (202).

[0110] Further, there is a gap between the first type through hole 211 (212) and the corresponding pad, and they are connected by a metal wire; and / or, the first type through hole 211 (212) is directly contacted and connected with the corresponding pad.

[0111] Furthermore, between adjacent PCB sub-boards 201 (202), the first type through holes 211 (212) for forming electrical connections are offset from each other.

[0112] Furthermore, each pad in the pad sublayer 231 (232) is spaced apart from the second type through hole 221 (222) on the corresponding PCB sub-board 201 (202) by a preset distance.

[0113] Regarding the principle, specific implementation and beneficial effects of the PCB, please refer to the relevant description of the PCB processing method mentioned above, which will not be repeated here.

[0114] It should be pointed out that the serial numbers of the steps in this embodiment do not limit the execution order of the steps.

[0115] It should be understood that the term "and / or" in this article is only a description of the association relationship of the associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article indicates that the associated objects before and after are in an "or" relationship.

[0116] The "plurality" appearing in the embodiments of the present application refers to two or more.

[0117] The first, second, etc. descriptions appearing in the embodiments of the present application are only used for illustration and distinction of the description objects. There is no order, nor do they indicate any special limitation on the number of devices in the embodiments of the present application, and cannot constitute any limitation on the embodiments of the present application.

[0118] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined by the claims.

Claims

1. A method for processing a printed circuit board PCB, characterized in that: include: Processing through holes on at least two PCB sub-boards respectively, wherein the through holes penetrate the corresponding PCB sub-boards and include first-type through holes and second-type through holes; Forming solder plate layers on adjacent surfaces of every two adjacent PCB sub-boards, respectively, wherein each solder pad in the solder plate layer corresponds one-to-one with the first type through hole on the corresponding PCB sub-board and realizes electrical connection; Performing welding processing on the solder plate layer of the adjacent PCB sub-board; Wherein, the first type of through holes are used to form electrical connections between adjacent PCB sub-boards, and the second type of through holes are used to form electrical connections inside and on the surface of the corresponding PCB sub-boards; Before respectively processing the through holes on at least two PCB sub-boards, the processing method further includes: obtaining a plurality of PCB single-layer boards; grouping the plurality of PCB single-layer boards, and performing a lamination process on each group of PCB single-layer boards to form at least two PCB sub-boards; The soldering sub-layers of the adjacent PCB sub-boards are subjected to soldering treatment, including: the soldering sub-layers of the PCB sub-boards obtained after the pressing treatment are subjected to soldering treatment.

2. The PCB processing method according to claim 1, characterized in that: There is a gap between the first type through hole and the corresponding pad, and they are connected by a metal wire; And / or, the first type through hole is directly connected to the corresponding pad.

3. The PCB processing method according to claim 1, characterized in that: Between adjacent PCB sub-boards, first type through holes for forming electrical connections are offset from each other.

4. The PCB processing method according to claim 1, characterized in that: There is a preset distance between each pad in the pad sublayer and the second type through hole on the corresponding PCB sub-board.

5. The PCB processing method according to claim 1, characterized in that: Before forming solder plate layers on adjacent surfaces of each two adjacent PCB sub-boards, the processing method further comprises: pouring conductive material into at least a portion of the through holes to form interlayer conductive through holes; And / or, electroplating is performed on the inner surface of at least a portion of the through hole to form an interlayer conductive through hole.

6. The PCB processing method according to claim 1, characterized in that: Before forming solder plate layers on adjacent surfaces of every two adjacent PCB sub-boards, the processing method further includes: performing solder resist treatment on the PCB sub-boards to form solder resist protective layers on the surfaces of the PCB sub-boards.

7. The PCB processing method according to claim 1, characterized in that: The material of the solder plate layer is selected from one or more of the following: Copper and its alloys, aluminum and its alloys, titanium and its alloys, platinum and its alloys, silver and its alloys, gold and its alloys.

8. The PCB processing method according to claim 1, characterized in that: The soldering process of the solder plate layer of the adjacent PCB sub-boards includes: Using soldering flux, soldering the solder plate layers of the adjacent PCB sub-boards; Wherein, the material of the soldering flux is selected from: tin and its alloy materials.

9. A printed circuit board PCB, characterized in that: include: At least two PCB daughter boards; Through holes are respectively located on the at least two PCB sub-boards, penetrate the corresponding PCB sub-boards, and include first-type through holes and second-type through holes; A solder plate layer is located on adjacent surfaces of every two adjacent PCB daughter boards, each solder pad in the solder plate layer corresponds to the first type through hole on the corresponding PCB daughter board and realizes electrical connection, and each solder pad in the solder plate layer is spaced from the second type through hole on the corresponding PCB daughter board by a preset distance; Wherein, the PCB is formed by welding the solder plate layers of adjacent PCB sub-boards; the first type of through-holes are used to form electrical connections between adjacent PCB sub-boards, and the second type of through-holes are used to form electrical connections inside and on the surface of the PCB sub-boards to which they belong; Among them, the number of the PCB sub-boards is at least two, which is formed by obtaining multiple PCB single-layer boards, grouping the multiple PCB single-layer boards, and pressing each group of PCB single-layer boards; the PCB is formed by welding the solder plate layer of the PCB sub-board obtained after the pressing process.

10. The PCB according to claim 9, characterized in that: include: There is a gap between the first type through hole and the corresponding pad, and they are connected by a metal wire; And / or, the first type through hole is directly connected to the corresponding pad.

11. The PCB according to claim 9, characterized in that: include: Between adjacent PCB sub-boards, first type through holes for forming electrical connections are offset from each other.

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