High-frequency mixed-pressing PCB and preparation method and application thereof

Abstract

The invention relates to a high-frequency mixed-pressing PCB and a preparation method and application thereof.The high-frequency mixed-pressing PCB comprises a mother board formed by pressing daughter boards of at least two base material types, at least one daughter board comprises a high-frequency core board and a high-frequency prepreg, and crossed blind holes are formed between the adjacent daughter boards; the crossed blind holes are filled with copper paste columns to form copper paste sintering holes of a vertical interconnection structure; a high-performance and high-reliability novel interconnection structure is constructed, high-yield and high-reliability production of the high-frequency mixed-pressed PCB is realized, the yield is up to 83.3-92.5%, and the extreme requirements of high-end electronic products on complex structures and electrical performance are met; the technical problems in high-frequency material mixed pressing, super-thick plate machining and copper paste sintering integration are solved.

Description

Technical Field

[0001] This invention relates to the field of high-end printed circuit board manufacturing technology, and in particular to a high-frequency mixed-pressure PCB board, its preparation method and application. Background Technology

[0002] With the rapid development of 5G communication, radar, and aerospace, extremely high requirements have been placed on high-frequency PCBs, such as low dielectric loss (Df), stable dielectric constant (Dk), high reliability, and complex three-dimensional interconnect structures. Traditional PCB manufacturing processes using conventional materials such as epoxy resin cannot meet the requirements of high-frequency signal transmission. High-frequency boards such as Rogers RO4350B and Taconic TLY-5Z are widely used, but their low resin content and high hardness characteristics differ significantly from conventional materials such as FR-4, posing significant challenges to processes such as multilayer lamination, drilling, and electroplating. Especially when achieving complex structures with high layer counts (e.g., 12 layers or more), high board thicknesses (e.g., >7mm), exposed copper areas (stepped trenches), and special interconnects (e.g., cross-blind vias), traditional processes face numerous bottlenecks.

[0003] Specifically, this includes: (1) Difficulty in mixing and laminating high-frequency materials: Different types of high-frequency materials and prepregs (PP) have poor matching characteristics in terms of flow properties and coefficient of thermal expansion (CTE), which easily leads to defects such as interlayer misalignment, voids, and resin deficiency during lamination, resulting in extremely low yield; (2) Difficulty in processing thick plates: When the thickness of the finished plate exceeds 7mm, there are problems such as low alignment accuracy, difficulty in chemical exchange, and difficulty in controlling line width tolerance in drilling, electroplating, exposure, and etching processes; (3) Difficulty in realizing special interconnects: If conventional mechanical drilling + electroplating is used for cross blind holes, the process flow is extremely long, and the uniformity of deep hole electroplating is difficult to guarantee, resulting in poor reliability. At present, copper paste sintering technology is an alternative solution that can solve the above problems to a certain extent, but there is no mature solution in the industry on how to integrate it into the complex process of high-frequency multilayer boards and solve its alignment, contamination, and reliability problems.

[0004] Therefore, there is an urgent need to develop a high-frequency mixed-press PCB board and its manufacturing process that can integrate high-frequency material mixing and pressing, thick plate processing and copper paste sintering interconnection, which is of great significance for promoting the development of high-end electronic equipment. Summary of the Invention

[0005] To address the aforementioned technical issues, the high-frequency mixed-press PCB board, its preparation method, and its application provided by this invention integrate high-frequency material mixed pressing, thick plate processing, and copper paste sintering interconnection technologies, achieving high performance, high yield, and high reliability. This provides the PCB industry with a highly applicable and reliable technical path.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a high-frequency hybrid PCB board, the high-frequency hybrid PCB board comprising a mother board formed by laminating sub-boards of at least two substrate types, at least one of the sub-boards comprising a high-frequency core board and a high-frequency prepreg, wherein cross blind vias are provided between adjacent sub-boards, and the cross blind vias are filled with copper paste pillars to form a vertical interconnect structure.

[0008] This invention solves the problem that existing PCBs cannot meet the requirements for high-frequency signal transmission by designing intersecting blind vias and filling the intersecting blind vias with copper paste pillars to form a vertical interconnect structure.

[0009] Preferably, the high-frequency core board includes RO4350B and / or TLY-5Z.

[0010] Preferably, the high-frequency prepreg comprises RO4450F and / or FR-28.

[0011] Preferably, the diameter of the cross blind hole is 0.15~0.25mm, for example, it can be 0.15mm, 0.18mm, 0.20mm, 0.22mm or 0.25mm.

[0012] Preferably, the mother plate is provided with at least one stepped groove, such as one, two or three, etc.; preferably one or two.

[0013] Preferably, the width of each stepped groove is independently 3 to 5 mm, for example, it can be 3 mm, 3.5 mm, 4 mm, 4.5 mm or 5 mm, etc.

[0014] Preferably, the thickness of the high-frequency mixed-voltage PCB board is >7mm, for example, it can be 7.1mm, 7.2mm, 7.3mm, 7.4mm, 7.5mm, 7.6mm or 7.7mm, etc.

[0015] In a second aspect, the present invention provides a method for preparing the high-frequency mixed-voltage PCB board described in the first aspect, the method comprising the following steps:

[0016] (1) Make each layer of sub-board separately;

[0017] (2) The surfaces to be pressed on each layer of the sub-board are browned, and laser ablation, copper paste filling and curing are performed sequentially at the preset blind hole positions;

[0018] (3) After riveting the sub-boards, lamination and post-processing are performed in sequence to obtain the high-frequency mixed-pressure PCB board.

[0019] The preparation method described in this invention obtains a vertical interconnect structure through laser ablation, copper paste filling and curing processes. Combined with subsequent lamination and post-processing steps, it achieves high yield and high reliability production of high-frequency mixed-layer PCBs. It solves many technical problems of traditional processes when realizing complex structures with high layer count (e.g., more than 12 layers), high board thickness (e.g., >7mm), local copper exposure (step grooves) and special interconnects (e.g., cross blind vias).

[0020] Preferably, when making each sub-board in step (1), the process further includes applying a PET film and a high-frequency prepreg to the surface of the outer high-frequency core board of at least one of the sub-boards and then pressing and bonding them together.

[0021] Preferably, the temperature for film lamination is 110~120℃, for example, it can be 110℃, 112℃, 115℃, 118℃ or 120℃.

[0022] Preferably, the linear speed of the film lamination is 0.4~0.6m / min, for example, it can be 0.4m / min, 0.45m / min, 0.5m / min, 0.55m / min or 0.6m / min.

[0023] Preferably, the browning treatment temperature in step (2) is 35~40℃, for example, it can be 35℃, 36℃, 37℃, 38℃, 39℃ or 40℃, etc.

[0024] Preferably, the browning treatment time in step (2) is 45~90s, for example, it can be 45s, 60s, 75s or 90s, etc.

[0025] Preferably, the laser type used for laser ablation in step (2) includes ultraviolet light or infrared light. Preferably, the energy density of laser ablation in step (2) is 10~100 J / cm². 2 For example, it could be 10 J / cm 2 30J / cm 2 50J / cm 2 80J / cm 2 or 100J / cm 2 wait.

[0026] Preferably, the endpoint of the laser ablation in step (2) is the target diameter of the cross blind hole.

[0027] Preferably, the preparation method further includes windowing the blind hole obtained by laser ablation in step (2).

[0028] Preferably, the curing temperature in step (2) is 80~90℃, for example, it can be 80℃, 82℃, 85℃, 88℃ or 90℃.

[0029] Preferably, the curing time in step (2) is 25 to 30 minutes, for example, 25 minutes, 26 minutes, 27 minutes, 28 minutes, 29 minutes or 30 minutes.

[0030] Preferably, the preparation method further includes applying PI tape to the preset step groove area and performing laser cutting to form the step groove before the laser ablation in step (2).

[0031] Preferably, the preparation method further includes opening a window in the pre-cured sheet of the preset stepped groove area before lamination in step (3).

[0032] Preferably, the lamination in step (3) includes sequential pressurization and heating, heat preservation and pressure holding, and cooling and depressurization.

[0033] It is worth noting that different lamination methods are used for different sub-boards in the lamination process. For example, it can be a simulated foil lamination method or lamination with two aluminum sheets on the top and bottom. Preferably, the final temperature of the pressurization and heating is 215~220℃, for example, 215℃, 216℃, 217℃, 218℃, 219℃ or 220℃, etc.

[0034] Preferably, the heating rate under pressure is 1.5~5.5℃ / min, for example, it can be 1.5℃ / min, 2℃ / min, 2.5℃ / min, 3℃ / min, 3.5℃ / min, 4℃ / min, 4.5℃ / min, 5℃ / min or 5.5℃ / min, etc.

[0035] Preferably, the final pressure of the pressurization and heating is 3~4MPa, for example, it can be 3MPa, 3.2MPa, 3.5MPa, 3.8MPa or 4MPa.

[0036] Preferably, the heat preservation and pressure holding time is 80~100min, for example, it can be 80min, 85min, 90min, 95min or 100min.

[0037] Preferably, the cooling and depressurization rate is ≤3℃ / min, for example, it can be 3℃ / min, 2.8℃ / min, 2.5℃ / min, 2.2℃ / min or 2℃ / min, etc.

[0038] Preferably, the post-processing in step (3) includes sequentially performing controlled depth milling of stepped grooves, drilling through holes, segmented copper plating, surface treatment, and shape machining.

[0039] Preferably, the segmented copper plating includes sequentially performing a first chemical copper plating, a first electroplated copper plating, a second chemical copper plating, a second electroplated copper plating, and a third electroplated copper plating.

[0040] Preferably, the post-processing further includes segmented plasma treatment after drilling the through-hole and before segmented copper plating.

[0041] Preferably, the segmented plasma treatment includes a first plasma treatment and a second plasma treatment performed sequentially.

[0042] Thirdly, the present invention provides an application of the high-frequency mixed-voltage PCB board described in the first aspect, wherein the high-frequency mixed-voltage PCB board is used in 5G communication, radar and aerospace fields.

[0043] The high-frequency mixed-voltage PCB board described in this invention is widely used in 5G communication, radar and aerospace fields due to its excellent yield and performance.

[0044] Compared with the prior art, the present invention has at least the following beneficial effects:

[0045] (1) The high-frequency mixed-voltage PCB board provided by the present invention forms a vertical interconnect structure by designing cross blind holes and filling them with copper paste pillars, which forms copper paste sintering holes. It innovatively provides a new type of high-performance and high-reliability interconnect structure, which meets the extreme requirements of high-end electronic products for complex structure and electrical performance.

[0046] (2) The high-frequency mixed-layer PCB preparation method provided by the present invention systematically solves the technical bottlenecks in the preparation of ultra-thick high-frequency mixed-layer PCBs in the current field by comprehensively addressing key technical points throughout the entire process, from material selection (RO4350B+TLY-5Z+RO4450F / FR-28), special lamination scheme (simulated foil coating method combined with aluminum sheet coating), ultra-thick plate electroplating scheme (multi-cycle plasma + segmented electroplating) to copper paste sintering integration (PET film lamination, laser ablation, manual paste filling and low-temperature curing followed by lamination sintering). Through precise PI tape application, PP window design, controlled depth milling, and innovative electroplating process, the processing yield of ultra-thick high-frequency boards and the long-term reliability of the final products are greatly improved. According to the test, the product yield reaches 83.3~92.5%, and the electrical performance, appearance, and reliability all meet the requirements of military products. The preparation method provides valuable technical path and practical experience for the manufacturing of high-frequency, high-speed, and high-multilayer PCBs, and has extremely high industry reference and promotion value.

[0047] (3) Application of the high-frequency mixed-voltage PCB board provided by the present invention: The high-frequency mixed-voltage PCB board, with its novel interconnection structure and specific manufacturing method, achieves high performance, high yield and high reliability, and is widely used in 5G communication, radar and aerospace fields. Attached Figure Description

[0048] Figure 1This is a schematic diagram of the structure of the high-frequency mixed-voltage PCB board provided in Embodiment 1 of the present invention.

[0049] Figure 2 This is a schematic diagram of the structure of the copper paste sintering hole on the high-frequency mixed-pressure PCB board provided in Embodiment 1 of the present invention.

[0050] Figure 3 This is a schematic diagram of the bonding of PET film and prepreg in the high-frequency mixed-pressure PCB board preparation method provided in Embodiment 1 of the present invention.

[0051] In the diagram: M, first copper paste sintering hole; N, second copper paste sintering hole; A, L3 stepped groove; B, L9 stepped groove; C, L10 stepped groove; a, first signal hole; b, second signal hole; c, first shielding hole; d, second shielding hole; e, third signal hole; f, third shielding hole; g, first non-metallized countersunk hole; h, second non-metallized countersunk hole; i, fourth shielding hole; j, fourth signal hole; k, mounting hole. Detailed Implementation

[0052] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments. However, the following examples are merely simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention is determined by the claims.

[0053] I. Implementation Examples

[0054] Example 1

[0055] This embodiment provides a high-frequency mixed-voltage PCB board, such as Figure 1 As shown, the high-frequency hybrid PCB board comprises 12 layers with a thickness of 7.7mm. Specifically, it includes a motherboard formed by laminating a first sub-board and a second sub-board. The first sub-board comprises layers L1 to L8, and the second sub-board comprises layers L9 to L12. The high-frequency core board of the first sub-board uses RO4350B (1.016mm), and the high-frequency core board of the second sub-board uses TLY-5Z (0.254mm). RO4450F (4mil) is sandwiched between adjacent high-frequency core boards in the first sub-board, and FR-28 (4mil) is sandwiched between adjacent high-frequency core boards in the second sub-board.

[0056] The high-frequency mixed-voltage PCB board includes a first signal hole a (0.6mm, k1-6), a second signal hole b (0.6mm, k3-6), a first shielding hole c (0.3mm, k5-8), a second shielding hole d (0.2mm, k9-10), a third signal hole e (0.6mm, k5-12), a third shielding hole f (0.3mm, k5-12), a first non-metallized countersunk hole g (2.1mm, k3-4), a second non-metallized countersunk hole h (3.2mm, k5-12), a fourth shielding hole i (0.3mm, k9-12), a fourth signal hole j (0.7mm, k9-12), and a mounting hole k (3.2mm, k9-12).

[0057] A 0.25mm diameter cross-shaped blind via is provided between the first and second sub-boards, and the cross-shaped blind via is filled with copper paste pillars to form a vertical interconnect structure, i.e., a copper paste sintering hole. The copper paste sintering hole includes a first copper paste sintering hole M and a second copper paste sintering hole N. The motherboard has three stepped grooves, namely L3 stepped groove A, L9 stepped groove B, and L10 stepped groove C. Among them, L3 stepped groove A exposes the L3 layer, with a section of copper skin protruding from the bottom of the step, and the rest is the substrate; L9 stepped groove B exposes the L9 layer, with an isolated hole plate at the bottom of the step, containing a metallized PHT pin hole, and the sidewall is gold-plated and milled through the L3 layer, but not to the L5 layer, with a depth control of ±0.1mm; L10 stepped groove C has a circuit at the bottom of the step.

[0058] This embodiment also provides a method for preparing the above-mentioned high-frequency mixed-voltage PCB board, the method comprising the following steps:

[0059] (1) Each sub-board is made separately; among them, the L1-L2, L3-L4, L1-L8, and L1-L12 layers are laminated using the simulated foil method; the L5-L8 and L9-L12 layers are laminated by adding two aluminum sheets on the top and bottom for lamination, and the thickness of the first sub-board after lamination is 6.7mm.

[0060] (2) The surfaces of each sub-board to be laminated are subjected to browning treatment, and laser ablation, copper paste filling and curing treatment are performed sequentially at the preset blind hole positions; the browning treatment temperature is 38℃ and the browning treatment time is 60s; the laser type of the laser ablation includes ultraviolet light with an energy density of 80J / cm². 2 The blind holes obtained by laser ablation in step (2) are opened to 0.4 mm; the filling copper paste is made by manually filling the holes with MPA500 copper paste at a 45° angle using a scraper; the solidification treatment is carried out at a temperature of 80° and a time of 30 min.

[0061] (3) After riveting the sub-boards, lamination and post-processing are performed in sequence to obtain the high-frequency mixed-pressure PCB board; the lamination includes sequential pressurization and heating, heat preservation and pressure holding, and cooling and depressurization, wherein the final temperature of pressurization and heating is 220℃, the heating rate is 3℃ / min, the final pressure is 3.45MPa, the heat preservation and pressure holding time is 90min, and the cooling and depressurization rate is 2℃ / min; the post-processing includes sequential controlled-depth milling of stepped grooves, drilling through holes, segmented plasma treatment, segmented copper plating, surface treatment, and shape processing; the segmented copper plating includes sequential first chemical copper plating, first electroplated copper plating, second chemical copper plating, second electroplated copper plating, and third electroplated copper plating; the segmented plasma treatment includes sequential first plasma treatment and second plasma treatment.

[0062] The specific steps are as follows:

[0063] L1-L2 layers: i. Material cutting, baking, inner layer circuitry (OPE-A-Jia / Jia-OPE-B), inner layer AOI, riveting, browning, and baking after browning; ii. Pressing, punching positioning holes, milling edges after pressing, marking PNL numbers, inner layer circuitry (OPE-A-L2), inner layer AOI, riveting, inner layer browning, and baking;

[0064] L3-L4 layers: i. Material cutting, baking, inner layer circuit (OPE-A-Jia / Jia-OPE-B), inner layer AOI, riveting, browning, and baking after browning; ii. Pressing, punching positioning holes, milling edges after pressing, marking PNL numbers, inner layer circuit (L3-OPE-B), inner layer AOI, riveting, inner layer browning, baking, laser cutting of PI and PP for L3 layer;

[0065] Layers L5-L8: i. Material preparation, board baking, inner layer circuitry (OPE5-L6 / L7-OPE8), inner layer AOI, riveting, browning, and baking after browning; ii. Lamination, copper reduction, drilling, plasma activation, flash plating, immersion copper, full board electroplating, resin plugging, grinding, copper reduction, hand polishing, inner layer circuitry (L5-OPE8), inner layer AOI, riveting, inner layer browning, and baking;

[0066] Layers L1-L8: lamination, punching positioning holes, milling edges, marking PNL numbers, drilling SZSK, drilling and inspecting holes, milling thin edges, plasma descaling, activation, copper plating, flash plating, copper plating, full board electroplating, electroplating inspection, single-hole plating, full board tin plating, full board tin plating followed by back drilling, alkaline etching, back drilling followed by tin removal, resin plugging, grinding, copper reduction, manual polishing, copper plating, full board electroplating, outer layer circuitry, acid etching, inner layer AOI, solder mask.

[0067] Layers L9-L12: i. Material preparation, baking, copper reduction, drilling (SZSK), post-drilling inspection, post-drilling baking, plasma activation, copper plating, flash plating, copper plating, full-board electroplating, electroplating inspection, resin plugging, grinding, post-grinding inspection, copper thickness measurement, copper reduction, manual grinding, copper plating, full-board electroplating, inner layer circuitry (OPE9-L10), inner layer AOI, punching rivet holes, inner layer browning, post-browning baking, L10 layer laser cutting PI, PP windowing; ii. Material preparation, baking, inner layer circuitry (L11-OPE12), inner layer AOI, punching rivets, browning, post-browning baking; iii. Pressing, punching positioning holes, milling edges, marking PNL numbers, single-sided copper reduction (L9), copper thickness measurement, drilling SZSK, post-drilling hole inspection, plasma activation, immersion copper flash plating, immersion copper full-board electroplating, electroplating inspection, resin plugging, grinding, post-grinding inspection, copper thickness measurement, via masking for copper reduction, manual grinding, plasma activation, immersion copper flash plating, immersion copper secondary electroplating, electroplating inspection, outer layer circuitry, acid etching, outer layer AOI, solder mask, silkscreen printing;

[0068] Layers L1-L12: i. Browning of L1-L8, baking after browning, laser ablation of copper paste sintering holes; ii. Browning of L9-L12, baking after browning, PET film and prepreg bonding onto L9-L12 sub-boards via laminator (120℃, 0.5m / min, 3 cycles), laser ablation of copper paste sintering holes, manual filling of copper paste, copper paste curing, riveting, and pressing; iii. Pressing, punching positioning holes, milling edges, marking PNL numbers, controlling the depth of L10 step groove C, drilling through holes, countersinking, controlling the depth of L3 step groove A and L9 step groove B, electroless gold plating, and shaping.

[0069] like Figure 2 The diagram shown is a schematic diagram of the copper paste sintering hole structure on the high-frequency mixed-pressure PCB board provided in this embodiment. It can be seen that the effective process of laser drilling of the prepreg and pressing the copper paste into the board to achieve cross-blind hole conduction can be achieved.

[0070] like Figure 3 The diagram shown is a schematic of the bonding of PET film and prepreg in the high-frequency mixed-pressure PCB board preparation method provided in this embodiment. It can be seen that the prepreg and PET film are completely bonded to the core board layer.

[0071] The high-frequency mixed-pressure PCB board prepared by the method described in this embodiment has a yield of 83.3% to 92.5% after testing, and its performance fully meets the requirements for use.

[0072] In summary, this invention systematically solves the technical bottleneck in the current field of manufacturing ultra-thick high-frequency mixed-pressure PCBs by designing intersecting blind vias and filling them with copper paste pillars to form a vertical interconnect structure, i.e., copper paste sintering vias. Combined with key technologies throughout the entire process, including material selection, special lamination schemes, ultra-thick plate electroplating schemes, and copper paste sintering integration, this invention greatly improves the processing yield of ultra-thick high-frequency boards and the long-term reliability of the final products, with a yield as high as 83.3~92.5%.

[0073] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A high-frequency mixed-voltage PCB board, characterized in that, The high-frequency hybrid PCB board includes a mother board formed by laminating sub-boards of at least two substrate types. At least one of the sub-boards includes a high-frequency core board and a high-frequency prepreg. Cross blind vias are provided between adjacent sub-boards, and the cross blind vias are filled with copper paste pillars to form a vertical interconnect structure.

2. The high-frequency mixed-voltage PCB board according to claim 1, characterized in that, The high-frequency core board includes RO4350B and / or TLY-5Z; Preferably, the high-frequency prepreg comprises RO4450F and / or FR-28.

3. The high-frequency mixed-voltage PCB board according to claim 1 or 2, characterized in that, The diameter of the intersecting blind holes is 0.15~0.25mm; Preferably, the mother plate has at least one stepped groove, preferably one or two. Preferably, the width of each of the stepped grooves is independently 3~5mm; Preferably, the thickness of the high-frequency mixed-voltage PCB board is >7mm.

4. A method for preparing a high-frequency mixed-voltage PCB board according to any one of claims 1 to 3, characterized in that, The preparation method includes the following steps: (1) Make each layer of sub-board separately; (2) The surfaces to be pressed on each layer of the sub-board are browned, and laser ablation, copper paste filling and curing are performed sequentially at the preset blind hole positions; (3) After riveting the sub-boards, lamination and post-processing are performed in sequence to obtain the high-frequency mixed-pressure PCB board.

5. The preparation method according to claim 4, characterized in that, Step (1) When making each sub-board, it also includes applying a PET film and a high-frequency prepreg to the surface of the outer high-frequency core board of at least one of the sub-boards and performing a pressing and bonding process. Preferably, the temperature for film lamination is 110~120℃; Preferably, the linear speed of the film lamination is 0.4~0.6m / min.

6. The preparation method according to claim 4 or 5, characterized in that, The temperature for the browning treatment in step (2) is 35~40℃; Preferably, the browning treatment time in step (2) is 45~90s; Preferably, the laser type used for laser ablation in step (2) includes ultraviolet light or infrared light; Preferably, the energy density of the laser ablation in step (2) is 10~100 J / cm². 2 ; Preferably, the endpoint of the laser ablation in step (2) is the target diameter of the cross blind hole; Preferably, the preparation method further includes windowing the blind hole obtained by laser ablation in step (2); Preferably, the curing temperature in step (2) is 80~90℃; Preferably, the curing time in step (2) is 25~30 min.

7. The preparation method according to any one of claims 4 to 6, characterized in that, The preparation method further includes applying PI tape to the preset step groove area and performing laser cutting to form the step groove before the laser ablation in step (2); Preferably, the preparation method further includes opening a window in the pre-cured sheet of the preset stepped groove area before lamination in step (3).

8. The preparation method according to any one of claims 4 to 7, characterized in that, The lamination in step (3) includes sequential pressurization and heating, heat preservation and pressure holding, and cooling and depressurization; Preferably, the final temperature of the pressurized heating is 215~220℃; Preferably, the heating rate under pressure is 1.5~5.5℃ / min; Preferably, the final pressure of the pressurization and heating is 3~4 MPa; Preferably, the heat preservation and pressure holding time is 80~100 minutes; Preferably, the cooling rate of the cooling and depressurization is ≤3℃ / min.

9. The preparation method according to any one of claims 4 to 8, characterized in that, The post-processing described in step (3) includes sequentially performing controlled depth milling of stepped grooves, drilling through holes, segmented copper plating, surface treatment, and shape machining; Preferably, the segmented copper plating includes sequentially performing a first chemical copper plating, a first electroplating copper plating, a second chemical copper plating, a second electroplating copper plating, and a third electroplating copper plating. Preferably, the post-processing further includes segmented plasma treatment after drilling the through hole and before segmented copper plating; Preferably, the segmented plasma treatment includes a first plasma treatment and a second plasma treatment performed sequentially.

10. An application of the high-frequency mixed-voltage PCB board according to any one of claims 1 to 3, characterized in that, The high-frequency hybrid PCB board is used in 5G communication, radar and aerospace fields.

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