Printed circuit board and method of manufacturing the same

Abstract

The present application relates to the technical field of circuit board, and discloses a printed circuit board and a manufacturing method thereof.The printed circuit board comprises a core substrate, first dielectric layers are arranged on opposite surfaces of the core substrate, and grooves penetrating through the first dielectric layers are formed in the first dielectric layers; rigid plates are arranged in the grooves respectively; the rigid plate with first through holes is arranged in the groove and fixed by a glue-dropping layer, then a second dielectric layer is arranged outside each first dielectric layer and rigid plate, a blind hole channel penetrating through the second dielectric layer, the first through holes and the glue-dropping layer is formed by drilling at positions corresponding to the first through holes, and the blind hole conductor in the blind hole channel realizes electrical interconnection between the outer layer circuit pattern and the inner layer circuit pattern.The rigidity of the rigid plate provides structural support and deformation constraint for the printed circuit board, and when the copper foil generates tensile stress due to heat, the rigid plate can resist local deformation caused by the stress, thereby reducing the overall warping of the product structure.

Description

Technical Field

[0001] This invention relates to the field of circuit board technology, and in particular to a printed circuit board and its manufacturing method. Background Technology

[0002] As printed circuit boards (PCBs) develop towards higher density, finer lines, and higher layer counts, PCB warpage has become a major problem restricting PCB development, leading to chip mounting failures and affecting long-term reliability. Currently, the main approach to suppressing PCB warpage is to focus on materials. For example, patent application CN102378478A discloses a PCB and a method for manufacturing a PCB. By adding inorganic particles composed of silicon dioxide or aluminum oxide to a core substrate made by impregnating a glass cloth core material with epoxy resin, the thermal expansion coefficient of the core substrate is reduced. At the same time, the thickness of the core substrate and the interlayer insulation layer is controlled to suppress warpage.

[0003] However, printed circuit boards are composites of copper foil and core substrate. Copper foil has a large coefficient of thermal expansion (approximately 17 ppm / ℃). When heated, the tensile stress generated by the copper foil causes the core substrate to deform along with the copper foil, resulting in a significant increase in the overall equivalent coefficient of thermal expansion of the product structure. Therefore, it is difficult to effectively offset the stress caused by the thermal expansion of copper foil by simply reducing the coefficient of thermal expansion of the core substrate itself. The warpage suppression effect is still limited by high-temperature operating conditions. Summary of the Invention

[0004] The technical problem to be solved by the present invention is that the existing printed circuit boards, by reducing the thermal expansion coefficient of the core substrate itself, are difficult to effectively offset the stress caused by the thermal expansion of copper foil, and the warpage suppression effect is still limited by high-temperature operating conditions.

[0005] To address the aforementioned technical problems, this invention provides a printed circuit board, including a core substrate, wherein inner layer circuit patterns are respectively provided on two opposite surfaces of the core substrate, the thickness direction of the printed circuit board is defined as the X direction, and the printed circuit board further includes an add-on assembly, which includes: The first dielectric layer is provided on both opposite surfaces of the core substrate along the X direction, and a groove penetrating the first dielectric layer is provided on each first dielectric layer. Rigid plates are respectively set in each groove, and each rigid plate is provided with multiple first through holes; Each adhesive layer is located in a groove to fix the corresponding rigid plate. Each adhesive layer has multiple second through holes. The second dielectric layer is provided on the outer surface of each first dielectric layer along the X direction. Each second dielectric layer is provided with a third via, and the outer surface of each second dielectric layer is provided with an outer layer circuit pattern. The first through hole, the second through hole, and the third through hole are connected one-to-one to form multiple blind via channels. Each blind via channel is set relative to the corresponding connection position on the inner layer circuit pattern in the X direction. There are multiple blind via conductors, each of which is set in a blind via channel and is used to electrically connect the outer layer circuit pattern and the inner layer circuit pattern.

[0006] Preferably, the layering component disposed on the first side of the core substrate in the X direction is defined as the first layering structure, and the layering component disposed on the second side of the core substrate is defined as the second layering structure. Multiple first layering structures and multiple second layering structures are provided, and the number of both is the same. Along the X direction, the first dielectric layer in the first and second add-on structures, which are close to the core substrate, is respectively disposed on two opposite surfaces of the core substrate. The first dielectric layer in the first augmentation structure away from the core substrate is respectively disposed on the second dielectric layer of the adjacent inner first augmentation structure, and each blind via conductor in the first augmentation structure is electrically connected to its outer circuit pattern and the outer circuit pattern of the adjacent inner first augmentation structure. The first dielectric layer in the second augmentation structure away from the core substrate is respectively disposed on the second dielectric layer of the adjacent inner second augmentation structure, and each blind via conductor in the second augmentation structure electrically connects its outer layer circuit pattern with the outer layer circuit pattern of the adjacent inner second augmentation structure.

[0007] Preferably, the rigid plate is made of glass, ceramic or glass-ceramic composite material.

[0008] Preferably, the rigid plate is made of iron-nickel alloy, copper-molybdenum-copper composite layer or carbon fiber reinforced metal matrix composite material.

[0009] Preferably, the rigid plate has a coefficient of thermal expansion ≤8ppm / ℃ and a Young's modulus ≥30GPa.

[0010] Preferably, both the first dielectric layer and the second dielectric layer include a prepreg and a copper foil, with the prepreg located inside the copper foil.

[0011] Preferably, the dispensing layer is an epoxy resin adhesive layer.

[0012] The present invention also provides a method for manufacturing the above-mentioned printed circuit board, comprising: S1. Along the X direction, each first dielectric layer is pressed onto the two opposite surfaces of the core substrate. S2. A groove is formed on each of the first dielectric layers, and the groove penetrates the first dielectric layer; S3. Apply adhesive layer to each groove and fix the rigid plate with the first through hole in each groove respectively; S4. Press each second dielectric layer onto the outer surface of each first dielectric layer; S5. Drill holes at the positions corresponding to the first through holes on each of the second dielectric layers to form blind hole channels that penetrate the second dielectric layer, the first through hole and the adhesive layer. S6. An outer layer circuit pattern is formed on the outer surface of each second dielectric layer, and a blind via conductor is formed in the blind via channel, so that the blind via conductor electrically connects the outer layer circuit pattern and the inner layer circuit pattern, forming a printed circuit board with an add-in component on both sides of the core substrate.

[0013] Preferred options also include: S7. Along the X direction, each of the first dielectric layers is pressed onto the outer surface of the outermost second dielectric layer; S8. Repeat steps S2 to S5 to complete the fabrication of blind via channels on the two second dielectric layers; S9. An outer layer circuit pattern is formed on the outer surface of each second dielectric layer, and a blind via conductor is formed in the blind via channel, so that the blind via conductor electrically connects the outer layer circuit pattern with the outer layer circuit pattern of the adjacent inner layer component, forming a printed circuit board with two layer components on both sides of the core substrate. S10. Repeat steps S7 to S9 once or more to form a printed circuit board with three or more add-on components on both sides of the core substrate.

[0014] Preferably, it further includes: S11, along the X direction, completing the outer layer solder resist and steel mesh ball planting on the outer surface of the outermost second dielectric layer.

[0015] Compared with the prior art, the printed circuit board of the preferred embodiment of the present invention has the following advantages: The printed circuit board provided by the preferred embodiment of the present invention has grooves formed on each of the first dielectric layers on both sides of the core substrate, exposing the inner layer circuit pattern on the surface of the core substrate. A rigid plate with a first through hole is placed in the groove and fixed by an adhesive layer. Then, a second dielectric layer is set on the outside of each first dielectric layer and the rigid plate. Then, holes are drilled at the corresponding positions of the first through holes to form blind hole channels that pass through the second dielectric layer, the first through holes and the adhesive layer. Blind hole conductors are formed in the blind hole channels. The blind hole conductors in the blind hole channels realize the electrical interconnection between the outer layer circuit pattern and the inner layer circuit pattern, thereby forming a rigid plate structure wrapped by the dielectric layer inside the printed circuit board. The rigidity of the rigid plate provides structural support and deformation constraint for the printed circuit board. When the copper foil is heated and tensile stress is generated, the rigid plate can resist the local deformation caused by the stress, thereby reducing the overall warpage of the product structure. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the core substrate of the printed circuit board provided in a preferred embodiment of the present invention; Figure 2This is a schematic diagram of the structure of the first dielectric layer laminated on the outer side of the core substrate of the printed circuit board provided in a preferred embodiment of the present invention; Figure 3 This is a schematic diagram of a printed circuit board with a groove for mounting a rigid plate formed on the first dielectric layer, provided by a preferred embodiment of the present invention. Figure 4 This is a schematic diagram of a rigid plate fixed in a groove in a printed circuit board according to a preferred embodiment of the present invention; Figure 5 This is a schematic diagram of a printed circuit board in which a second dielectric layer is laminated on the outside of a first dielectric layer, according to a preferred embodiment of the present invention. Figure 6 This is a schematic diagram of the structure for forming blind via channels in a printed circuit board according to a preferred embodiment of the present invention; Figure 7 This is a schematic diagram of the structure of a printed circuit board in which a dry film is attached to the outside of the second dielectric layer and an outer layer circuit pattern and blind via conductor are formed. Figure 8 This is a schematic diagram of the structure of a printed circuit board after an add-on component is fabricated on a core substrate, according to a preferred embodiment of the present invention. Figure 9 This is a schematic diagram of the structure of a printed circuit board after two add-on components are fabricated on a core substrate, according to a preferred embodiment of the present invention. Figure 10 This is a schematic diagram of a printed circuit board structure with two add-on components and solder mask forming according to a preferred embodiment of the present invention. Figure 11 This is a schematic diagram of a printed circuit board structure with four add-on components and solder mask forming, provided by a preferred embodiment of the present invention.

[0017] In the diagram, 1. Core substrate; 101. Inner layer circuit pattern; 20. First dielectric layer; 201. Groove; 30. Second dielectric layer; 301. Third through hole; 302. Outer layer circuit pattern; 2. Prepreg; 3. Copper foil; 4. Rigid board; 401. First through hole; 5. Adhesive layer; 501. Second through hole; 6. Blind via channel; 7. Blind via conductor; 8. Dry film; 9. Solder resist; 10. Solder ball. Detailed Implementation

[0018] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings and preferred embodiments. The following preferred embodiments are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0019] In the description of this invention, it should be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0020] It should be understood that the terms "first," "second," etc., are used in this invention to describe various types of information, but these terms are not limited to them; they are only used to distinguish information of the same type from one another. For example, without departing from the scope of this invention, "first" information may also be referred to as "second" information, and similarly, "second" information may also be referred to as "first" information.

[0021] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0022] like Figures 1 to 11 As shown, a preferred embodiment of the present invention provides a printed circuit board, including a core substrate 1, with inner layer circuit patterns 101 respectively formed on two opposite surfaces of the core substrate 1. The thickness direction of the printed circuit board is defined as the X direction. The printed circuit board also includes a layer-adding component, which includes: The first dielectric layer 20 is provided on both opposite surfaces of the core substrate 1 along the X direction, and each first dielectric layer 20 is provided with a groove 201 that penetrates the first dielectric layer 20. Rigid plates 4 are respectively disposed in each groove 201, and each rigid plate 4 is provided with multiple first through holes 401; Each adhesive layer 5 is disposed in each groove 201 to fix the corresponding rigid plate 4. Each adhesive layer 5 is provided with multiple second through holes 501. The second dielectric layer 30 is provided on the outer surface of each first dielectric layer 20 along the X direction. Each second dielectric layer 30 is provided with a third through hole 301, and each outer surface of the second dielectric layer 30 is provided with an outer layer circuit pattern 302. The first through hole 401, the second through hole 501 and the third through hole 301 are connected one-to-one to form a plurality of blind via channels 6. Each blind via channel 6 is set relative to the corresponding connection position on the inner layer circuit pattern 101 in the X direction. Multiple blind via conductors 7 are provided, and each blind via conductor 7 is respectively set in each blind via channel 6 for electrically connecting the outer layer circuit pattern 302 and the inner layer circuit pattern 101.

[0023] The printed circuit board provided in the preferred embodiment of the present invention has grooves 201 formed on each of the first dielectric layers 20 on both sides of the core substrate 1, exposing the inner layer circuit pattern 101 on the surface of the core substrate 1. A rigid plate 4 with a first through hole 401 is placed in the groove 201 and fixed by an adhesive layer 5. Then, a second dielectric layer 30 is provided on the outside of each first dielectric layer 20 and the rigid plate 4. A blind hole channel 6 is formed by drilling at the position corresponding to the first through hole 401, passing through the second dielectric layer 30, the first through hole 401 and the adhesive layer 5. A blind hole conductor 7 is formed in the blind hole channel 6. The blind hole conductor 7 in the blind hole channel 6 realizes the electrical interconnection between the outer layer circuit pattern 302 and the inner layer circuit pattern 101, thereby forming a rigid plate 4 structure wrapped by the dielectric layer inside the printed circuit board. The rigidity of the rigid plate 4 provides structural support and deformation constraint for the printed circuit board. When the copper foil 3 is heated and tensile stress is generated, the rigid plate 4 can resist the local deformation caused by the stress, thereby reducing the overall warpage of the product structure.

[0024] Specifically, the layering component disposed on the first side of the core substrate 1 in the X direction is defined as the first layering structure, and the layering component disposed on the second side of the core substrate 1 is defined as the second layering structure. Multiple first layering structures and multiple second layering structures are provided, and the number of both is the same. Along the X direction, the first dielectric layer 20 in the first and second add-layer structures close to the core substrate 1 is respectively disposed on the two opposite surfaces of the core substrate 1. The first dielectric layer 20 in the first layered structure away from the core substrate 1 is respectively disposed on the second dielectric layer 30 of the adjacent inner first layered structure, and each blind via conductor 7 in the first layered structure is electrically connected to its outer circuit pattern 302 and the outer circuit pattern 302 of the adjacent inner first layered structure. The first dielectric layer 20 in the second layer structure away from the core substrate 1 is respectively disposed on the second dielectric layer 30 of the adjacent inner second layer structure, and each blind via conductor 7 in the second layer structure is electrically connected to its outer layer circuit pattern 302 and the outer layer circuit pattern 302 of the adjacent inner second layer structure.

[0025] The first and second add-in structures are provided in multiples, and the number of both is the same, thus forming two or more add-in components. Each add-in component is stacked sequentially along the thickness direction of the core substrate 1, so that each add-in component includes a rigid plate 4 and its corresponding blind via interconnection structure. Thus, a rigid plate 4 is embedded in each layer of the multilayer printed circuit board. Each rigid plate 4 provides rigid constraint to the printed circuit board in its area. At the same time, the blind via conductors 7 between layers achieve interlayer electrical interconnection by electrically connecting the outer layer circuit pattern 302 of the adjacent add-in components. When the copper foil 3 of each layer is heated and generates tensile stress, the rigid plate 4 of each layer resists the deformation of its area, so that the warping of the multilayer structure as a whole is suppressed in each add-in component.

[0026] Specifically, the rigid plate 4 is made of glass, ceramic, or glass-ceramic composite material. Utilizing the inherent low coefficient of thermal expansion and high Young's modulus of these materials, when the rigid plate 4 is embedded inside the circuit board, its high Young's modulus provides strong structural support for the dielectric and circuit layers in the area, resisting the tensile stress generated by the thermal expansion of the copper foil 3. At the same time, its low coefficient of thermal expansion means that it hardly deforms when the temperature changes, thus effectively constraining the surrounding dielectric layer to follow the expansion trend of the copper foil 3 and reducing the overall warpage of the product structure. Furthermore, all of the above materials are non-conductive and will not interfere with signal transmission when embedded in the circuit board, making them suitable for high-frequency signal transmission circuit boards. In addition, glass, ceramic, or glass-ceramic composite materials have high dimensional stability and heat resistance, maintaining a stable structural shape in subsequent high-temperature processes or high-temperature operating environments, ensuring a continuous and reliable suppression effect on warpage during long-term use.

[0027] Specifically, the rigid plate 4 is made of iron-nickel alloy, copper-molybdenum-copper composite layer or carbon fiber reinforced metal matrix composite material. The above materials also have low thermal expansion coefficient and high Young's modulus characteristics, which can effectively reduce the overall warping of the product structure. At the same time, the above materials are all conductive materials. After being embedded in the circuit board, in addition to serving as a rigid skeleton to resist warping, they can also be used to connect power supply or ground, serving as a power layer or ground layer and playing an electromagnetic shielding role, further reducing electromagnetic interference during signal transmission and improving signal integrity.

[0028] Specifically, the coefficient of thermal expansion of rigid plate 4 is ≤8ppm / ℃, and the Young's modulus is ≥30GPa.

[0029] Specifically, both the first dielectric layer 20 and the second dielectric layer 30 include a prepreg 2 and a copper foil 3. Along the X direction, the prepreg 2 is located inside the copper foil 3. The prepreg 2 is a semi-cured sheet material composed of resin and glass fiber cloth. It can soften, flow, and eventually cure under heating and pressure. In the multilayer printed circuit board, it serves as an adhesive layer and an insulating layer. When pressed, the prepreg 2 melts and flows under heat, filling the gap between the rigid plate 4 and the groove 201, as well as the first through hole 401 on the rigid plate 4. It fills the gaps between the rigid plate 4 and the core substrate 1, and between the rigid plate 4 and the second dielectric layer 30, so that the rigid plate 4 is tightly wrapped in the cured prepreg 2 material, preventing the rigid plate 4 from shifting and ensuring that the rigid plate 4's anti-warping effect is continuous and stable. At the same time, after curing, the prepreg 2 becomes a solid dielectric layer with insulating properties, which is tightly bonded to the copper foil 3 on its outer side.

[0030] Specifically, the 5th dispensing layer is an epoxy resin adhesive layer.

[0031] The present invention also provides a method for manufacturing the above-mentioned printed circuit board, comprising: S1. Along the X direction, prepreg 2 is respectively disposed on the two opposite surfaces of the core substrate 1, and copper foil 3 is respectively disposed on the outside of the prepreg 2. High temperature and high pressure are applied to press the prepreg 2. After the resin in the prepreg 2 melts and flows, it is cured. The prepreg 2 and the copper foil 3 together form the first dielectric layer 20, thereby pressing each first dielectric layer 20 onto the two opposite surfaces of the core substrate 1.

[0032] S2. Using laser processing, grooves 201 are formed on each first dielectric layer 20. The grooves 201 penetrate the first dielectric layer 20 and have a depth of 0.05mm.

[0033] S3. Clean the grooves 201 by removing the adhesive, then apply epoxy resin adhesive to the bottom of the grooves 201. Pre-cure the epoxy resin adhesive at 100°C for 1 minute to make the first through hole 401 on the rigid plate 4 correspond to the position of the inner layer circuit pattern 101. After baking and curing at 150°C for 5 minutes, fix the rigid plate 4 in the grooves 201 through the adhesive layer 5.

[0034] S4. On both sides of the circuit board to which the rigid plate 4 is fixed, a second dielectric layer 30 composed of a prepreg 2 and a copper foil 3 is respectively provided, and high temperature and high pressure are applied. During the pressing process, the resin of the prepreg 2 flows into the first through hole 401 of the rigid plate 4 and fills it.

[0035] S5. Using laser drilling, a hole is drilled at the position of the first through hole 401 corresponding to the rigid plate 4, penetrating the second medium layer 30 to form a third through hole 301, penetrating the resin filled in the first through hole 401 and penetrating the adhesive layer 5 to form a second through hole 501, and the first through hole 401, the second through hole 501 and the third through hole 301 are connected to form a blind hole channel 6.

[0036] S6. Plasma treatment, browning removal treatment, fluffing and adhesive removal, and chemical copper plating are performed on the blind via channel 6 to achieve cleaning and metallization of the blind via channel 6. A dry film 8 with a thickness of 45μm is attached to the outside of the second dielectric layer 30. After exposure at 85mJ energy and development at a speed of 1.2m / min, pattern electroplating is performed to complete the pattern with a copper thickness of 25μm. At the same time, the filling electroplating of the blind via channel 6 is completed. After film removal and baking, the circuit is etched. An outer layer circuit pattern 302 is formed on the outside of the second dielectric layer 30. A blind via conductor 7 that electrically connects the outer layer circuit pattern 302 and the inner layer circuit pattern 101 is formed in the blind via channel 6, forming a printed circuit board with an add-on component on both sides of the core substrate 1.

[0037] S7. Along the X direction, the prepreg 2 and copper foil 3 are used to form a first dielectric layer 20 and pressed onto the outer surface of the second dielectric layer 30, which is located on both sides.

[0038] S8. Repeat steps S2 to S5 to complete the fabrication of blind via channels 6 on the two second dielectric layers 30.

[0039] S9. An outer layer circuit pattern 302 is fabricated on the outer surface of each second dielectric layer 30. The fabrication process is the same as in step S6. A blind via conductor 7 is formed in the blind via channel 6, so that the blind via conductor 7 electrically connects the outer layer circuit pattern 302 with the outer layer circuit pattern 302 of the adjacent inner layer addition component, forming a printed circuit board with two addition components on both sides of the core substrate 1.

[0040] S10. Repeat steps S7 to S9 once or more to form a printed circuit board having three or more add-on components on both sides of the core substrate 1.

[0041] S11. Along the X direction, apply solder resist 9 ink to the outer surface of the outermost second dielectric layer 30 to complete the solder resist 9 roller coating, exposure, development, UV curing and baking curing, and then use solder balls 10 to plant the stencil.

[0042] In summary, the printed circuit board provided in the preferred embodiment of the present invention has grooves formed on each of the first dielectric layers on both sides of the core substrate, exposing the inner layer circuit pattern on the surface of the core substrate. A rigid plate with a first through hole is placed in the groove and fixed by an adhesive layer. Then, a second dielectric layer is set on the outside of each first dielectric layer and the rigid plate. A blind hole channel is formed by drilling at the corresponding position of the first through hole, passing through the second dielectric layer, the first through hole and the adhesive layer. A blind hole conductor is formed in the blind hole channel. The blind hole conductor in the blind hole channel realizes the electrical interconnection between the outer layer circuit pattern and the inner layer circuit pattern, thereby forming a rigid plate structure wrapped by the dielectric layer inside the printed circuit board. The rigid plate provides structural support and deformation constraint for the printed circuit board by utilizing the rigidity of the rigid plate. When the copper foil is heated and tensile stress is generated, the rigid plate can resist the local deformation caused by the stress, thereby reducing the overall warpage of the product structure.

[0043] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present invention, and these improvements and substitutions should also be considered within the scope of protection of the present invention.

Claims

1. A printed circuit board, comprising a core substrate (1), wherein inner layer circuit patterns (101) are respectively provided on two opposite surfaces of the core substrate (1), characterized in that, The thickness direction of the printed circuit board is defined as the X direction. The printed circuit board further includes an add-on assembly, which includes: The first dielectric layer (20) is provided on both opposite surfaces of the core substrate (1) along the X direction, and each first dielectric layer (20) has a groove (201) that penetrates the first dielectric layer (20). Rigid plates (4) are respectively disposed in each of the grooves (201), and each of the rigid plates (4) is provided with a plurality of first through holes (401). The adhesive layer (5) is respectively provided in each of the grooves (201) for fixing the corresponding rigid plate (4). Each adhesive layer (5) is provided with a plurality of second through holes (501). The second dielectric layer (30) is provided on the outer surface of each of the first dielectric layers (20) along the X direction. Each of the second dielectric layers (30) is provided with a third through hole (301) and an outer layer circuit pattern (302) is provided on the outer surface of each of the second dielectric layers (30). The first through hole (401), the second through hole (501) and the third through hole (301) are connected one-to-one to form a plurality of blind via channels (6), and each of the blind via channels (6) is respectively set relative to the corresponding connection position on the inner layer circuit pattern (101) in the X direction; Multiple blind via conductors (7) are provided, and each blind via conductor (7) is respectively disposed in each blind via channel (6) for electrically connecting the outer layer circuit pattern (302) and the inner layer circuit pattern (101).

2. The printed circuit board according to claim 1, characterized in that, The layering component disposed on the first side of the core substrate (1) in the X direction is defined as the first layering structure, and the layering component disposed on the second side of the core substrate (1) is defined as the second layering structure. The first layering structure and the second layering structure are provided in multiples, and the number of the two is the same. Along the X direction, the first dielectric layer (20) in the first layered structure and the second layered structure near the core substrate (1) are respectively disposed on two opposite surfaces of the core substrate (1); The first dielectric layer (20) in the first layered structure away from the core substrate (1) is respectively disposed on the second dielectric layer (30) of the adjacent inner side of the first layered structure, and each of the blind via conductors (7) in the first layered structure is electrically connected to its outer layer circuit pattern (302) and the outer layer circuit pattern (302) of the adjacent inner side of the first layered structure. The first dielectric layer (20) in the second augmentation structure away from the core substrate (1) is respectively disposed on the second dielectric layer (30) of the adjacent inner side of the second augmentation structure, and each of the blind via conductors (7) in the second augmentation structure is electrically connected to its outer layer circuit pattern (302) and the outer layer circuit pattern (302) of the adjacent inner side of the second augmentation structure.

3. The printed circuit board according to claim 1 or 2, characterized in that, The rigid plate (4) is made of glass, ceramic or glass-ceramic composite material.

4. The printed circuit board according to claim 1 or 2, characterized in that, The rigid plate (4) is made of iron-nickel alloy, copper-molybdenum-copper composite layer or carbon fiber reinforced metal matrix composite material.

5. The printed circuit board according to claim 1 or 2, characterized in that, The rigid plate (4) has a thermal expansion coefficient of ≤8ppm / ℃ and a Young's modulus of ≥30GPa.

6. The printed circuit board according to claim 1 or 2, characterized in that, Both the first dielectric layer (20) and the second dielectric layer (30) include a prepreg (2) and a copper foil (3), with the prepreg (2) located inside the copper foil (3) along the X direction.

7. The printed circuit board according to claim 1 or 2, characterized in that, The dispensing layer (5) is an epoxy resin adhesive layer.

8. A method for manufacturing a printed circuit board as described in any one of claims 1-7, characterized in that, include: S1. Along the X direction, each first dielectric layer (20) is pressed onto the two opposite surfaces of the core substrate (1); S2. A groove (201) is formed on each of the first dielectric layers (20), and the groove (201) penetrates the first dielectric layer (20). S3. Apply adhesive layer (5) to each groove (201) and fix the rigid plate (4) with the first through hole (401) in each groove (201); S4. Press each of the second dielectric layers (30) onto the outer surface of each of the first dielectric layers (20); S5. Drill holes at the positions corresponding to the first through hole (401) on each of the second dielectric layers (30) to form blind hole channels (6) that penetrate the second dielectric layer (30), the first through hole (401) and the adhesive layer (5). S6. An outer layer circuit pattern (302) is formed on the outer surface of each second dielectric layer (30), and a blind via conductor (7) is formed in the blind via channel (6) so that the blind via conductor (7) electrically connects the outer layer circuit pattern (302) and the inner layer circuit pattern (101) to form a printed circuit board with an add-in component on both sides of the core substrate (1).

9. The method for manufacturing a printed circuit board according to claim 8, characterized in that, Also includes: S7. Along the X direction, each of the first dielectric layers (20) is pressed onto the outer surface of the outermost second dielectric layer (30); S8. Repeat steps S2 to S5 to complete the fabrication of blind via channels (6) on the two second dielectric layers (30); S9. An outer layer circuit pattern (302) is formed on the outer surface of each second dielectric layer (30), and a blind via conductor (7) is formed in the blind via channel (6) so that the blind via conductor (7) electrically connects the outer layer circuit pattern (302) with the outer layer circuit pattern (302) of the adjacent inner layer assembly, thereby forming a printed circuit board with two layer assemblies on both sides of the core substrate (1). S10. Repeat steps S7 to S9 once or more to form a printed circuit board having three or more add-on components on both sides of the core substrate (1).

10. The method for manufacturing a printed circuit board according to claim 8 or 9, characterized in that, Also includes: S11. Along the X direction, complete the outer layer solder resist (9) and steel mesh ball planting on the outer surface of the outermost second dielectric layer (30).

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