Multilayer printed circuit board for power circuit
By improving the insulation layer structure and manufacturing process of multilayer printed circuit boards, and using FR-4 material and composite insulation design, the problems of poor voltage resistance and poor heat dissipation of traditional circuit boards have been solved, achieving high-temperature stability and efficient heat dissipation.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-21
- Publication Date
- 2026-03-27
AI Technical Summary
Traditional power circuit boards lack high temperature resistance and mechanical strength, are prone to interlayer delamination, and are affected by heat dissipation and electrical performance. In particular, the problems of interlayer isolation and heat dissipation optimization have not been effectively solved in high-power scenarios.
The design employs an insulating layer structure, including a first filler layer, an intermediate isolation layer, and a second filler layer. FR-4 material is used to replace traditional inks, combined with an FR-4 solder resist layer and a semi-cured epoxy resin film. Through a composite insulating structure and gradient pressing process, heat resistance and heat dissipation efficiency are improved.
It achieves improved temperature resistance to over 260℃, 3 times higher mechanical impact resistance, 15-20% higher thermal conductivity, and improved electrical performance, making it suitable for high-frequency power circuits.
Smart Images
Figure CN224054491U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to printed circuit board manufacturing technical field especially relates to a multilayer printed circuit board for power circuit. BACKGROUND
[0002] Traditional power circuit board adopts epoxy resin ink as the solder mask, which is insufficient in high temperature resistance and mechanical strength, and is prone to cause interlayer peeling or pad oxidation. In addition, the multilayer pressing in the existing process often causes bubbles due to uneven filling, affecting heat dissipation and electrical performance. For example, patent CN87107023 proposes a metal core multilayer printed circuit board manufacturing method, but does not solve the problem of interlayer isolation and heat dissipation optimization in high power scenarios. In particular, the multilayer printed circuit board for planar transformer requires higher electrical performance and needs to have high stability and good voltage resistance. Therefore, there is an urgent need for a multilayer circuit board scheme that takes into account voltage resistance, heat dissipation efficiency and process stability. SUMMARY
[0003] The technical problem to be solved by the utility model is to provide a multilayer printed circuit board for power circuit, which can solve the problems of poor voltage resistance and poor heat dissipation effect by improving the interlayer structure and preparation process of the multilayer printed circuit board.
[0004] To solve the above technical problems, the utility model discloses a multilayer printed circuit board for power circuit, which comprises at least two double-sided copper-clad plates and two single-layer copper sheets, the two double-sided copper-clad plates are stacked in the height direction, and an insulating layer is arranged between the two double-sided copper-clad plates, one of the single-layer copper sheets is stacked above the upper double-sided copper-clad plate, and the other single-layer copper sheet is stacked below the lower double-sided copper-clad plate, an insulating layer is arranged between the single-layer copper sheet and the double-sided copper-clad plate, and an anti-solder layer is arranged on the outer side of each single-layer copper sheet.
[0005] The insulating layer comprises a first filling adhesive layer, an intermediate isolation layer and a second filling adhesive layer which are sequentially stacked from top to bottom.
[0006] The first filling adhesive layer and the second filling adhesive layer are both semi-cured epoxy resin adhesive films.
[0007] The intermediate isolation layer is an FR-4 isolation layer.
[0008] The anti-solder layer is an FR-4 anti-solder layer.
[0009] A semi-cured epoxy resin adhesive film is further arranged between the single-layer copper sheet and the anti-solder layer.
[0010] The double-sided copper-clad plate comprises a first copper foil, a PP semi-cured sheet and a second copper foil which are sequentially stacked from top to bottom.
[0011] Compared with the prior art, the multilayer printed circuit board for power current has the following beneficial effects: stress buffering and dielectric strength improvement can be realized by arranging the insulating layer, FR-4 material is used to replace traditional ink, the temperature resistance is improved to above 260 DEG C, no delamination is caused in thermal cycle test, the mechanical impact resistance is improved by 3 times, the composite insulating structure can effectively improve the thermal conductivity, and the problems of poor voltage resistance and poor heat dissipation effect in the prior art are solved. BRIEF DESCRIPTION OF DRAWINGS
[0012] In order to more clearly illustrate the technical scheme in the embodiments of the present application, the drawings needed to be used in the embodiment description will be briefly introduced, and obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained without creative labor on the basis of these drawings.
[0013] Figure 1 The structural schematic diagram of the multilayer printed circuit board for power circuit in the embodiment is shown in the figure.
[0014] Figure 2 The structural schematic diagram of the double-sided copper-clad plate in the embodiment is shown in the figure. DETAILED DESCRIPTION
[0015] In order to make the person skilled in the art better understand the present application, the technical scheme in the embodiments of the present application will be clearly and completely described in the following with reference to the drawings of the embodiments of the present application, and obviously, the described embodiments are only some embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of the present application.
[0016] The terms "first", "second", etc. in the specification and claims of the present application and the above drawings are used to distinguish different objects, and are not used to describe a specific order. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, device, product or end including a series of steps or units is not limited to the listed steps or units, but can optionally include steps or units not listed, or can optionally include other steps or units inherent to the process, method, product or end.
[0017] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are they necessarily mutually exclusive of one another. As will be apparent to those of ordinary skill in the art, embodiments described herein can be combined with other embodiments.
[0018] The utility model discloses a kind of concrete implementation of multilayer printed circuit board for power circuit, see Figure 1 , multilayer printed circuit board, including two double-sided copper-clad plates and two single-layer copper sheets, two double-sided copper-clad plates are stacked in height direction, and an insulating layer is provided between the two double-sided copper-clad plates, one of the single-layer copper sheets is stacked above the upper double-sided copper-clad plate, and the other single-layer copper sheet is stacked below the lower double-sided copper-clad plate, an insulating layer is provided between the single-layer copper sheet and the double-sided copper-clad plate, and an anti-soldering layer is provided on the outer side of each single-layer copper sheet. It should be noted that the number of double-sided copper-clad plates can be selectively set according to actual needs, and can be three, four, five, etc.
[0019] As a preferred scheme, the insulating layer includes a first filling adhesive layer, an intermediate isolation layer and a second filling adhesive layer stacked in order from top to bottom, and a semi-cured epoxy resin adhesive film is further provided between the single-layer copper sheet and the anti-soldering layer. Specifically, the first filling adhesive layer and the second filling adhesive layer are both semi-cured epoxy resin adhesive films, and the intermediate isolation layer is an FR-4 isolation layer. Using FR-4 instead of traditional ink can effectively improve heat resistance, thereby further improving the electrical performance of the multilayer printed circuit board. Using a semi-cured epoxy resin adhesive film as a filling adhesive to fill each copper sheet can achieve flat filling of etched recesses, ensuring the stability and flatness of the interlayer structure.
[0020] Optionally, the double-sided copper-clad plate includes a first copper foil, a PP semi-cured sheet and a second copper foil stacked in order from top to bottom. In this embodiment, the anti-soldering layer is an FR-4 anti-soldering layer, which can further improve the mechanical strength and high temperature resistance of the product.
[0021] The multilayer printed circuit board of the present embodiment can achieve stress buffering and dielectric strength improvement through the provision of an insulating layer, uses FR-4 material instead of traditional ink, improves the temperature resistance to above 260℃, has no delamination in thermal cycle test, improves the mechanical impact resistance by 3 times, and the composite insulating structure can effectively improve the thermal conductivity, solving the problems of poor voltage resistance and poor heat dissipation effect in the past. The FR-4 anti-soldering layer has a temperature resistance improved to above 200℃, an adhesion improved by 30%, and the filling adhesive uniformity improves the heat dissipation efficiency by 15% to 20%, the multilayer compression structure reduces the parasitic inductance, and is suitable for MHz level high frequency power circuit.
[0022] The utility model discloses a kind of preparation methods of multilayer printed circuit board for power circuit, comprising the following steps.
[0023] Step 1, prefabricated double-sided copper-clad plate, select two T2 red copper foil, thickness range 0.1mm~0.5mm, surface roughness≤1.5 μm, select PP prepreg, thickness 0.05mm~0.2mm before curing, according to the lamination mode of first copper foil, PP prepreg, second copper foil, compression, compression temperature 120℃~180℃, compression pressure 10MPa~30MPa, after compression, cut after cooling and curing, and prefabricated double-sided copper-clad plate is prepared.T2 red copper thickness is 0.1mm~0.5mm, which can reduce circuit resistance, reduce skin effect loss, and PP prepreg is mainly used for bonding copper layer, providing good insulation, and ensuring electrical performance.
[0024] Step 2, once patterning, the double-sided copper-clad plate in step 1 is sequentially drilled, copper is deposited, exposed, and etched to form a predetermined circuit and a hole site in the double-sided copper-clad plate in step 1. This step is a traditional process. After drilling, chemical copper deposition forms a conductive layer in the hole. Exposure and etching define the circuit.
[0025] Step 3, multilayer compression, first fill each copper surface of the double-sided copper-clad plate etched in step 2 with semi-cured epoxy resin film; then stack multiple double-sided copper-clad plates and place FR-4 isolation layers between adjacent semi-cured epoxy resin films to form a copper-clad plate assembly; select two single copper sheets, stack one single copper sheet with semi-cured epoxy resin film filled on the bottom surface above the copper-clad plate assembly, and stack the other single copper sheet with semi-cured epoxy resin film filled on the top surface below the copper-clad plate assembly; during the stacking of the two single copper sheets, place FR-4 isolation layers between the single copper sheets and the two semi-cured epoxy resin films of the copper-clad plate assembly; finally, position each single copper sheet and double-sided copper-clad plate with rivets or jigs, and compress and form with a compression machine to obtain a multilayer compression circuit board.
[0026] The filled glue (semi-cured epoxy resin film) can cover the recessed copper surface after etching, ensuring a smooth surface. In addition, it can also eliminate bubbles with vacuum compression to ensure flatness. The FR-4 isolation layer is inserted between the films to provide insulation and mechanical strength between the layers. Rivets or jigs are used for positioning to ensure that the interlayer offset is less than 5 μm.
[0027] Step 4, secondary patterning, the multilayer compression circuit board in step 3 is drilled, copper is deposited, exposed, and etched to form a predetermined circuit and a hole site in the single copper sheet above and below the copper-clad plate assembly. Repeating the drilling and copper deposition after the first compression ensures the reliability of the interlayer interconnection. The two patterning processes reduce copper waste and improve the yield rate to 98.5%.
[0028] Step 5, press FR-4 solder mask layer and text layer on the outer side of the single-sided copper sheet. Preferably, in step 5, first fill the copper surface of the single-sided copper sheet with a semi-cured epoxy resin film, and then press the FR-4 solder mask layer, which can further improve the insulation performance and flatness.
[0029] Step 6, process the outer shape of the multi-layer press circuit board.
[0030] The preparation method of the multi-layer printed circuit board for power circuit of the embodiment can reduce copper waste by using a secondary patterning process, improve the yield to 98.5%, and fill the semi-cured adhesive film to make the bubble rate of the product after pressing <0.1%, the dielectric strength ≥40kV / mm. The process design is reasonable, which can effectively improve the electrical performance of the multi-layer printed circuit board and improve the production efficiency. Through the design of composite insulation structure, the innovation of FR-4 solder mask layer and gradient pressing process, the heat dissipation bottleneck and interlayer reliability problem in high power scene are systematically solved, which is especially suitable for high-end fields such as new energy automobile electric control, 5G base station power supply and the like.
[0031] Finally, it should be noted that: the disclosed multi-layer printed circuit preparation method for power circuit of the embodiment of the utility model is only the preferred embodiment of the utility model, and is only used to illustrate the technical scheme of the utility model, not to limit it; although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand; it can still modify the technical scheme recorded in the foregoing embodiments, or make equivalent replacement for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical scheme deviate from the spirit and scope of the technical scheme of the embodiments of the utility model.
Claims
1. A multilayer printed circuit board for a power circuit, characterized in that, The printed circuit board comprises at least two double-sided copper-clad plates and two single-layer copper sheets, the two double-sided copper-clad plates are stacked in the height direction, and an insulating layer is arranged between the two double-sided copper-clad plates, one of the single-layer copper sheets is stacked above the upper double-sided copper-clad plate, the other single-layer copper sheet is stacked below the lower double-sided copper-clad plate, an insulating layer is arranged between the single-layer copper sheet and the double-sided copper-clad plate, and an anti-solder layer is arranged on the outer side of each single-layer copper sheet.
2. A multi-layer printed circuit board for power circuits according to claim 1, characterized in that, The insulating layer comprises a first filling adhesive layer, an intermediate isolation layer and a second filling adhesive layer which are sequentially stacked from top to bottom.
3. A multi-layer printed circuit board for power circuits according to claim 2, characterized in that, The first filling adhesive layer and the second filling adhesive layer are both semi-cured epoxy resin adhesive films.
4. A multi-layer printed circuit board for power circuits according to claim 2, characterized in that, The intermediate isolation layer is an FR-4 isolation layer.
5. A multi-layer printed circuit board for power circuits according to claim 1, wherein, The anti-solder layer is an FR-4 anti-solder layer.
6. A multi-layer printed circuit board for power circuits according to claim 1, characterized in that, A semi-cured epoxy resin adhesive film is further arranged between the single-layer copper sheet and the anti-solder layer.
7. A multi-layer printed circuit board for power circuits according to claim 1, characterized in that, The double-sided copper-clad plate comprises a first copper foil, a PP semi-cured sheet and a second copper foil which are sequentially stacked from top to bottom.