CN103582322B - Multilayer circuit board and preparation method thereof - Google Patents

Abstract

A method for manufacturing a multilayer circuit board, comprising: providing a plurality of copper foil substrates; making the copper foil layer of each copper foil substrate to form a conductive circuit layer to obtain a plurality of first circuit substrates; A film is attached to one surface of the film, a through hole is formed in the film, and a conductive material is formed in the through hole, and the conductive material and the conductive circuit layer are electrically connected to each other to obtain a second circuit substrate; part of the two first circuit substrates Laying a film on the surface, forming a through hole in the film, forming a conductive material in the through hole, and electrically conducting the conductive material and the conductive circuit layer to obtain a third circuit substrate; laminating the third circuit substrate, the second circuit substrate and One, two, or three of the first circuit substrates, or laminated copper foils at the same time to form a laminated substrate, and press the laminated substrate or make the copper foil into a conductive circuit pattern, so as to obtain multiple layer circuit board. The invention also provides a multilayer circuit board prepared by the method.

Description

Multilayer circuit board and its manufacturing method

technical field

The invention relates to circuit board manufacturing technology, in particular to a multilayer circuit board and a manufacturing method thereof.

Background technique

With the development of electronic products in the direction of miniaturization and high speed, circuit boards are also developing from single-sided circuit boards, double-sided circuit boards to multi-layer circuit boards. Multilayer circuit board refers to a circuit board with multiple layers of conductive circuits, which has more wiring area and higher interconnection density, so it is widely used, see the literature Takahashi, A. Ooki, N. Nagai, A. Akahoshi, H. Mukoh, A. Wajima, M. Res. Lab., High density multilayer printed circuit board for HITAC M-880，IEEE Trans. on Components, Packaging, and Manufacturing Technology, 1992, 15(4): 418-425.

At present, multilayer circuit boards are usually produced by a build-up method, that is, they are produced in a manner of stacking layers. The method for making a multilayer circuit board using the traditional build-up method includes steps: the first step is to make an inner layer board, which includes at least one insulating material layer and two conductive circuit layers, and the two conductive circuit layers The circuit layers are electrically connected to each other through at least one conductive hole. In the second step, an adhesive sheet and a copper foil layer are respectively pressed on the two conductive circuit layers of the inner layer board, wherein the copper foil layer passes through the adhesive sheet and the conductive circuit layer of the inner layer board Layer bonding, selectively etching the copper foil layer to form an outermost conductive circuit pattern on the copper foil layer, thereby forming a multi-layer circuit substrate; the third step is to use laser drilling and other methods on the multi-layer At least one blind hole is formed on the circuit substrate, and the at least one blind hole is electroplated to electrically conduct the copper foil layer with the conductive circuit layer of the inner layer board; the fourth step is to form at least one blind hole on the multilayer circuit substrate. through holes, and electroplate the through holes to electrically connect the two outermost conductive circuit patterns of the multilayer circuit substrate, thus obtaining a multilayer circuit board. If you need a multilayer circuit board with more layers, follow the similar method of the second to third steps, that is, continue to press a copper foil on the two outermost conductive circuit patterns of the multilayer circuit substrate, select The copper foil layer is permanently etched to electrically connect the conductive circuit layer that needs to be connected. In this way, a multilayer circuit board with more layers can be obtained.

However, in the manufacturing process of the above-mentioned multi-layer circuit board, every time a layer is added, a pressing process is required. When making a circuit board with more layers, the number of times of pressing is correspondingly more, which is not conducive to the process. simplification, the production cost is relatively high, and the production efficiency is relatively low.

Contents of the invention

In view of this, it is necessary to provide a method for manufacturing a multilayer circuit board and the multilayer circuit board obtained by the method, so as to improve the manufacturing efficiency of the multilayer circuit board.

A method for manufacturing a multilayer circuit board, comprising the steps of: providing N copper-clad substrates, wherein N is a natural number greater than or equal to 4, each of the copper-clad substrates includes an insulating layer and is bonded to the insulating layer The first copper foil layer and the second copper foil layer on both sides; the first copper foil layer of each of the copper-clad substrates is made to form a first conductive circuit pattern, and the second copper foil of each of the copper-clad substrates is Layer fabrication forms a second conductive circuit pattern, and the first conductive circuit pattern and the second conductive circuit pattern are electrically connected to each other through at least one conductive hole, so that the N copper-clad substrates are made into N first circuit substrates; Take N-2M+1 first circuit substrates among the N first circuit substrates, where M is a natural number greater than or equal to 2, and N is greater than 2M-1, and among the N-2M+1 first circuit substrates Each of the first conductive circuit patterns in the first circuit substrate in a circuit substrate is pasted with a first film, and the first film has at least one first through hole, and the at least one first through hole The first conductive material is filled inside, and the first conductive material is electrically connected to the adjacent first conductive circuit pattern, so that N-2M+1 first circuit substrates are made into N-2M+1 second circuit substrates ; Take M-1 first circuit substrates among the N first circuit substrates, and attach the first conductive circuit pattern surface in each of the first circuit substrates in the M-1 first circuit substrates The second film, a third film is attached to the surface of the second conductive circuit pattern in each of the M-1 first circuit substrates, and the second film has at least one second through hole, The third film has at least one third through hole, and the at least one second through hole is filled with a second conductive material, and the second conductive material is electrically connected to the adjacent first conductive circuit pattern, and the second conductive material is electrically connected to the adjacent first conductive circuit pattern. The at least one third through hole is filled with a third conductive material, and the third conductive material is electrically connected to the adjacent second conductive circuit pattern, so that the M-1 first circuit substrates are made into M- 1 third circuit substrate; and laminating the remaining M first circuit substrates, the N-2M+1 second circuit substrates and the M-1 third circuit substrates at one time to form a 2N-layer circuit board, In the 2N-layer circuit board, adjacent insulating layers are bonded together by the first film, the second film or the third film, and the two first circuit substrates are located at the end of the 2N-layer circuit board. On the outer two sides, either a first circuit substrate and a second circuit substrate are located on the outermost sides of the 2N-layer circuit board, or two second circuit substrates are located on the outermost two sides of the 2N-layer circuit board.

A method for manufacturing a multilayer circuit board, comprising the steps of: providing N copper-clad substrates, wherein N is a natural number greater than or equal to 3, each of the copper-clad substrates includes an insulating layer and is bonded to the insulating layer The first copper foil layer and the second copper foil layer on both sides; the first copper foil layer of each of the copper-clad substrates is made to form a first conductive circuit pattern, and the second copper foil of each of the copper-clad substrates is Layer fabrication forms a second conductive circuit pattern, and the first conductive circuit pattern and the second conductive circuit pattern are electrically connected to each other through at least one conductive hole, so that the N copper-clad substrates are made into N first circuit substrates; Take N-2M first circuit substrates among the N first circuit substrates, where M is a natural number, and N is greater than 2M, and each of the first circuit substrates among the N-2M first circuit substrates The surface of the first conductive circuit pattern in the circuit substrate is pasted with a first film, the first film has at least one first through hole, and a first conductive material is filled in the first through hole, and the first conductive material and The adjacent first conductive circuit patterns are electrically connected to each other, so that the N-2M first circuit substrates are made into N-2M second circuit substrates; M first circuit substrates are selected from the N first circuit substrates. A circuit substrate, a second film is pasted on the surface of the first conductive circuit pattern in each of the M first circuit substrates, and each first circuit in the M first circuit substrates is The surface of the second conductive circuit pattern in the substrate is pasted with a third film, the second film has at least one second through hole, each of the third films has at least one third through hole, and the at least one The second through hole is filled with a second conductive material, and the second conductive material is electrically connected to the adjacent first conductive circuit pattern, and a third conductive material is filled in the at least one third through hole, and the third through hole is filled with a third conductive material. The conductive material is electrically connected to the adjacent second conductive circuit patterns, so that the M first circuit substrates are made into M third circuit substrates; the first copper foil sheet is provided, and the remaining M first circuit substrates are pressed together at one time. A circuit substrate, N-2M second circuit substrates, M third circuit substrates, and the first copper foil to form a 2N+1 layer circuit substrate, in the 2N+1 layer circuit substrate, The adjacent insulating layers are bonded together by the first film, the second film or the third film, and the adjacent insulating layers and the first copper foil are bonded together by the first film or the second film, And the first copper foil is located on the outermost side of the 2N+1 layer circuit substrate, and one of the first circuit substrates or one of the second circuit substrates is located on the outermost side of the 2N+1 layer circuit substrate one side; and making the first copper foil into a conductive circuit pattern through selective etching to obtain a 2N+1 layer circuit board.

A method for manufacturing a multilayer circuit board, comprising the steps of: providing N copper-clad substrates, wherein N is a natural number greater than or equal to 3, each of the copper-clad substrates includes an insulating layer and is bonded to the insulating layer The first copper foil layer and the second copper foil layer on both sides; the first copper foil layer of each of the copper-clad substrates is made to form a first conductive circuit pattern, and the second copper foil of each of the copper-clad substrates is Layer fabrication forms a second conductive circuit pattern, and the first conductive circuit pattern and the second conductive circuit pattern are electrically connected to each other through at least one conductive hole, so that the N copper-clad substrates are made into N first circuit substrates; Take N-2M-1 first circuit substrates among the N first circuit substrates, where M is a natural number, and N is greater than 2M+1, and among the N-2M-1 first circuit substrates The surface of the first conductive circuit pattern in each of the first circuit substrates is pasted with a first film, and the first film has at least one first through hole, and the first conductive circuit is filled in the at least one first through hole. materials, the first conductive material and the corresponding first conductive circuit patterns are electrically connected to each other, so that N-2M-1 first circuit substrates are made into N-2M-1 second circuit substrates; M+1 first circuit substrates are taken from the first circuit substrates, and a second film is pasted on the surface of the first conductive circuit pattern in each of the first circuit substrates of the M+1 first circuit substrates, The surface of the second conductive circuit pattern in each of the M+1 first circuit substrates is pasted with a third film, the second film has at least one second through hole, and the third The film has at least one third through hole, and the second conductive material is filled in the at least one second through hole, and the second conductive material is electrically connected to the adjacent first conductive circuit pattern, and the at least one The third through hole is filled with a third conductive material, and the third conductive material is electrically connected to the adjacent second conductive circuit pattern, so that the M+1 first circuit substrates are made into M+1 third Circuit substrate: provide the first copper foil and the second copper foil, press the first copper foil, the remaining M first circuit substrates, N-2M-1 second circuit substrates, M +1 of the third circuit substrate and the second copper foil to form a 2N+2 layer circuit substrate, in the 2N+2 layer circuit substrate, the first copper foil and the second copper foil The foils are respectively located on the outermost two sides of the 2N+2-layer circuit substrate, and the adjacent insulating layers are bonded together by the first film, the second film or the third film, and the adjacent insulating layers and the second film are bonded together. A copper foil sheet and adjacent insulating layers and second copper foil sheets are all bonded together through the first film or the second film or the third film; and the first copper foil and the second The copper foils are respectively made into conductive circuit patterns through selective etching to obtain a 2N+2 layer circuit board.

A method for manufacturing a multilayer circuit board, comprising the steps of: providing N+1 copper-clad substrates, wherein N is a natural number greater than or equal to 1, and each of the copper-clad substrates includes an insulating layer and is bonded to the insulating layer. The first copper foil layer and the second copper foil layer on opposite sides of the layer; the first copper foil layer of each of the copper-clad substrates is made to form a first conductive circuit pattern, and the second copper-clad substrate of each of the copper-clad substrates is The copper foil layer is fabricated to form a second conductive circuit pattern, and the first conductive circuit pattern and the second conductive circuit pattern are electrically connected to each other through at least one conductive hole, so that the N+1 copper-clad substrates are made into N+1 first circuit substrates; take N first circuit substrates among the N+1 first circuit substrates, and the first conductor in each of the first circuit substrates in the N first circuit substrates The surface of the circuit pattern is pasted with a first film, the first film has at least one first through hole, and a first conductive material is filled in the at least one first through hole, and the first conductive material is connected with the adjacent first The conductive circuit patterns are electrically connected to each other, so that the N first circuit substrates are made into N second circuit substrates; the N second circuit substrates and the remaining first circuit substrate are pressed together at one time to form 2N+2 layer circuit board, in the 2N+2 layer circuit board, the first film in each of the second circuit substrates is closer to the first circuit substrate than the second conductive circuit pattern, and between adjacent insulating layers Bonded together by the first film.

A multilayer circuit board is formed by the above-mentioned multilayer circuit board manufacturing method. The multilayer circuit board includes a multilayer insulating layer, a multilayer film and a multilayer conductive circuit pattern. The opposite two sides of each insulating layer Each side of the film is provided with a layer of conductive circuit patterns, and the conductive circuit patterns on both sides of each layer of insulating layer are electrically connected through at least one conductive hole arranged in the insulating layer, and each layer of film is provided with a layer of said Conductive circuit patterns, and the conductive circuit patterns on opposite sides of each layer of film are electrically connected through the conductive material arranged in the film, and the conductive material in the film is formed by printing conductive paste.

The multilayer circuit board manufacturing method provided by this technical solution is to manufacture multiple circuit substrates at the same time, and then form a film on one or both surfaces of some circuit substrates by bonding, and form a through hole in the film and form a conductive material . In this way, according to the needs, stack the copper foil, the circuit substrate bonded with the film and the conductive material, or stack the circuit substrate not bonded with the film at the same time, so that a multilayer circuit board can be obtained by one pressing. Since a plurality of circuit boards can be produced simultaneously, the time for circuit board production can be shortened. Since each circuit substrate is manufactured separately, compared with the method of layer-by-layer stacking in the prior art, the yield rate of circuit board production can be improved.

Description of drawings

FIG. 1 is a schematic cross-sectional view of a copper-clad substrate provided by the first embodiment of the technical solution.

2 is a schematic cross-sectional view of a first circuit substrate formed after forming conductive holes, a first conductive circuit pattern and a second conductive circuit pattern on the copper-clad substrate in FIG. 1 provided by the first embodiment of the technical solution.

Fig. 3 is provided by the first embodiment of the technical solution, where the first film and release film are laminated on the first conductive circuit pattern of the first circuit substrate in Fig. 2, and the protective film is pasted on the second conductive circuit pattern, And a schematic cross-sectional view after pre-pressing the first circuit substrate, the first film, the release film and the protective film.

4 is a schematic cross-sectional view of a second circuit substrate formed after forming a first blind hole on the first film in FIG. 3 and forming a first conductive material in the first blind hole provided by the first embodiment of the technical solution.

5 is a schematic cross-sectional view of a third circuit substrate provided by the first embodiment of the technical solution.

Fig. 6 is the first embodiment of the technical solution provided by the pressure bonding of a first copper foil, a third circuit substrate, a first circuit substrate, another third circuit substrate, a second circuit substrate and a second circuit substrate. A schematic cross-sectional view of the whole formed after the copper foil.

Fig. 7 is a schematic cross-sectional view after the first copper foil in Fig. 6 is fabricated to form a third conductive circuit pattern and the second copper foil is fabricated to form a fourth conductive circuit pattern provided by the first embodiment of the technical solution.

Fig. 8 is a ten-layer circuit formed after the first solder resist layer is formed on the third conductive circuit pattern in Fig. 7 and the second solder resist layer is formed on the fourth conductive circuit pattern provided by the first embodiment of the technical solution Schematic cross-section of the plate.

FIG. 9 is a schematic structural diagram of a fourteen-layer circuit board obtained by a stacking method of the second embodiment when N=7 and M=3 provided by the technical solution.

Fig. 10 is a schematic structural diagram of a fourteen-layer circuit board obtained by a stacking method of the third embodiment when N=7 and M=3 provided by the technical solution.

FIG. 11 is a schematic structural diagram of a thirteen-layer circuit substrate obtained by a stacking method of the fourth embodiment when N=6 and M=3 provided by the technical solution.

FIG. 12 is a schematic structural diagram of a thirteen-layer circuit substrate obtained by a stacking method of the fifth embodiment when N=6 and M=2 provided by the technical solution.

FIG. 13 is a schematic structural diagram of a sixteen-layer circuit substrate obtained by a stacking method of the sixth embodiment when N=7 and M=3 provided by the technical solution.

FIG. 14 is a schematic structural diagram of a sixteen-layer circuit substrate obtained by a stacking method of the seventh embodiment when N=7 and M=2 provided by the technical solution.

Fig. 15 is a schematic structural diagram of an eight-layer circuit board stacked when N=3 provided by the technical solution.

Description of main component symbols

Copper clad substrate 10 Insulation 11 first copper foil layer 12 Second Copper Foil Layer 13 conductive hole 14 first conductive pattern 15 Second Conductive Line Pattern 16 first circuit substrate 110 first film 17 Release film 18 protective film 19 first via 20 first conductive material twenty one Second Circuit Substrate 120 second film twenty two third film twenty three Second via twenty four third via 25 second conductive material 26 third conductive material 27 third circuit substrate 130 first copper foil 28 Second copper foil 29 third conductive line pattern 30 Fourth Conductive Circuit Pattern 31 first solder mask 32 Second solder mask 33 Ten-layer circuit board 100 Fourteen-layer circuit board 200, 210 Thirteen-layer circuit board 220, 230 Sixteen-layer circuit substrate 240, 250 Eight-layer circuit board 260

The following specific embodiments will further illustrate the present invention in conjunction with the above-mentioned drawings.

detailed description

The multilayer circuit board provided by the technical solution and the manufacturing method thereof will be further described in detail below in conjunction with the accompanying drawings and multiple embodiments.

The manufacturing method of the ten-layer circuit board provided by the first embodiment of the technical solution includes the following steps:

In the first step, referring to FIG. 1 , four copper-clad substrates 10 are provided. Each copper clad substrate 10 includes an insulating layer 11 and a first copper foil layer 12 and a second copper foil layer 13 bonded to opposite sides of the insulating layer 11 .

The copper-clad substrate 10 may be a glass fiber cloth-based copper-clad substrate, a paper-based copper-clad substrate, a composite-based copper-clad substrate, an aramid fiber non-woven fabric-based copper-clad substrate, or a synthetic fiber-based copper-clad substrate. Of course, two, three, five or more copper-clad substrates 10 can also be selected according to the requirements of the number of layers of the circuit board to be formed.

In the second step, please refer to FIG. 2, at least one first conductive hole 14 is formed on each of the copper-clad substrates 10, each of the first copper foil layers 12 is fabricated to form a first conductive circuit pattern 15, and each A second copper foil layer 13 is made to form a second conductive circuit pattern 16, and the first conductive circuit pattern 15 and the second conductive circuit pattern 16 are electrically connected to each other through the at least one first conductive hole 14, thereby obtaining four first circuits. Substrate 110.

The formation of the first conductive hole 14 can adopt the following method: first, a through hole is formed on the copper clad substrate 10 by mechanical drilling, and the through hole successively passes through the first copper foil layer 12, the insulation layer 11 and the second copper foil layer 13, and desmear the through hole; then, use electroplating to electroplate metal such as copper, silver or gold inside the through hole, so as to obtain the first A conductive hole 14 . Preferably, copper is electroplated inside the through hole. More preferably, when electroplating is performed, the through hole is completely filled through an electroplating hole filling process. Of course, it is also possible to electroplate metal on the hole wall of the through hole first to form the first conductive hole 14, and then fill the resin in the through hole; The conductive paste is filled inside, and the conductive paste is cured to form the first conductive hole 14 .

Those skilled in the art can also understand that it is also possible to form blind holes on the copper-clad substrate 10 by laser ablation first, and the blind holes penetrate the first copper foil layer 12 and the insulating layer 11, and then use The electroplating filling process fills the inside of the blind hole with electroplating metal, so as to obtain the first conductive hole 14; it is also possible to first form the first copper foil layer 12 by opening a copper window. The position of the conductive hole 14 is etched to open the copper window, and then the insulating layer 11 is ablated by laser ablation to form a blind hole, and then, the electroplating metal is filled inside the blind hole by an electroplating hole filling process, Thus, the first conductive hole 14 is obtained.

The first conductive circuit pattern 15 and the second conductive circuit pattern 16 can be formed by image transfer process and etching process.

In this embodiment, the first conductive circuit patterns 15 and the second conductive circuit patterns 16 on the four first circuit substrates 110 are set according to the actual circuit boards to be produced, and the first conductive circuit patterns 16 in each copper-clad substrate 10 The arrangement of the conductive circuit pattern 15 and the second conductive circuit pattern 16 may be the same or different.

The third step, referring to FIGS. 3-4 , is to make one of the four first circuit substrates 110 into a second circuit substrate 120 . The manufacturing method of the second circuit substrate 120 may include the following steps:

First, on the first conductive circuit pattern 15 of the first circuit substrate 110, the first film 17 and the release film 18 are sequentially laminated, and on the second conductive circuit pattern 16 of the first circuit substrate 110, the protective film19. Next, pre-press the first circuit substrate 110, the first film 17, the release film 18 and the protective film 19, so that the first film 17 and the first circuit substrate 110 are bonded together, and at the same time The protection film 19 is glued on the second conductive pattern 16 . The release film 18 is removed. Then, at least one first through hole 20 is formed on the first film 17, the first through hole 20 penetrates through the first film 17, and part of the first conductive circuit pattern 15 passes through the first through hole. 20 with the bottom exposed. Furthermore, a first conductive material 21 is formed in the first through hole 20 , so that the first conductive material 21 and the first conductive circuit pattern 15 are electrically connected to each other. Finally, the protective film 19 is removed to obtain the second circuit substrate 120 .

In this embodiment, the first film 17 is a prepreg, which can be a glass fiber cloth prepreg, a paper-based prepreg, a composite-based prepreg, an aramid fiber non-woven fabric prepreg, a synthetic fiber prepreg, or a pure resin prepreg.

Wherein, the function of pre-pressing is to heat the first film 17 to make the first film 17 have a certain viscosity, so as to bond with the first circuit substrate 110 together. The pre-lamination temperature, pre-lamination pressure, and pre-lamination time of the first film 17 are far less than the temperature, pressure, and time required for the lamination of the first film 17. Therefore, the first film 17 after pre-lamination still retains its semi-cured properties. In this embodiment, the pre-lamination temperature range of the first film 17 is 60-110° C., the pre-lamination time range is 10-60 seconds, and the pre-lamination pressure range is 5-15 kg/cm2. The pressing temperature range corresponding to the first film 17 is 180-250°C, the pressing time range is 60-120 minutes, and the pressing pressure range is 200-300 kg/cm2. Preferably, the pre-pressing temperature of the first film 17 is 80°C, the pre-pressing time is 30 seconds, the pre-pressing pressure is 10kg/cm2, the pressing temperature is 210°C, and the pressing time For 80 minutes, the pressing pressure is 250kg/cm2.

In this embodiment, the release film 18 is a Mylar sheet (mylar), which is used to protect the first film 17 and prevent the first film 17 from contacting objects (such as The steel plate or pressing fixture used for pre-pressing) are bonded together and cannot be separated. The release film 18 can also be other release materials such as polyethylene release film or polypropylene release film.

The protective film 19 is used to protect the second conductive circuit pattern 16 to prevent the second conductive circuit pattern 16 from being oxidized and damaged in the subsequent step of pre-lamination or making the first conductive hole. In this embodiment, the protective film 19 includes a polyester film and a low-tack adhesive layer attached to the polyester film. Of course, the polyester film can also be other polymer films such as polyethylene film and polypropylene film, as long as it has good heat resistance.

In this embodiment, the first through hole 20 is formed by laser drilling. In addition, because the laser drilling process uses a high-energy laser to ablate the first film 17 to form a hole, some residues will be generated during ablation, so preferably, after the laser drilling, the first through hole 20 for desmear treatment, and the residue can be removed by plasma desmear treatment process or chemical desmear process.

In this embodiment, the first through hole 20 is filled with the first conductive material 21 by printing metal conductive paste. The metal conductive paste can be conductive copper paste, conductive silver paste, conductive solder paste, etc., preferably conductive copper paste. Specifically, firstly, the metal conductive paste is filled in the first through hole 20 by screen printing; then, the conductive metal paste is baked to solidify the conductive metal paste to form the first conductive material 21 . The temperature at which the conductive metal paste is baked is lower than the temperature at which the first film 17 is cured, so as not to affect the semi-cured properties of the first film 17 .

In addition, before laminating the first film 17 and the release film 18, preferably, the first conductive circuit pattern 15 can be subjected to surface roughening treatment, such as browning treatment, to strengthen the first film. 17 and the bonding force between the first conductive circuit pattern 15.

Of course, multiple second circuit substrates 120 can also be produced according to the number of circuit board layers to be formed.

In the fourth step, please refer to FIG. 5 , two of the four first circuit substrates 110 are made into two third circuit substrates 130 . The manufacturing method of each third circuit substrate 130 may include the following steps:

First, the second film 22 and release film are laminated on the first conductive circuit pattern 15 of the first circuit substrate 110, and the third film is laminated on the second conductive circuit pattern 16 of the first circuit substrate 110. 23 and release film. Secondly, the first circuit substrate 110 , the second film 22 and the third film 23 are pre-pressed so that the second film 22 , the first circuit substrate 110 and the third film 23 are bonded together. Then, the release films on both sides of the first circuit substrate 110 are removed. Furthermore, at least one second through hole 24 is formed on the second film 22, the second through hole 24 penetrates through the second film 22, and allows part of the first conductive circuit pattern 15 to pass through the second through hole. The bottom of the hole 24 is exposed, and at least one third through hole 25 is formed on the third film 23. The third through hole 25 penetrates through the third film 23 and allows part of the second conductive circuit pattern 16 to pass through the third film 23. The bottom of the three through holes 25 is exposed. Finally, a second conductive material 26 is formed in the second through hole 24, and a third conductive material 27 is formed in the third through hole 25, so that the second conductive material 26 and the first conductive circuit The patterns 15 are electrically connected to each other, and the third conductive material 27 is electrically connected to the second conductive circuit pattern 16 to obtain the third circuit substrate 130 .

In this embodiment, the positions and numbers of the second through holes 24 and the third through holes 25 of the two third circuit substrates 130 are set according to the actual circuit boards to be produced, and each of the third circuit substrates 130 The positions and numbers of the second through holes 24 and the third through holes 25 can be the same or different.

In addition, this step is similar to the above-mentioned third step. The material and function of the release film in this step are the same as those of the release film 18 in the third step, and the pre-pressing conditions and functions are also the same as those of the third step. The conditions and effects of the pre-compression are the same. The formation method of the second through hole 24 and the third through hole 25 may also be the same as that of the first through hole 20 in the third step. The method of forming the second conductive material 26 and the third conductive material 27 in the second through hole 24 and the third through hole 25 can also be the same as that of forming the first conductive material 21 in the first through hole 20 in the third step. the same way. In addition, preferably, the second through hole 24 and the third through hole 25 are also desmeared after the laser drilling, so as to remove the residue in the second through hole 24 and the third through hole 25, The residue removal treatment can adopt plasma desmear treatment process or chemical desmear treatment process. Preferably, before laminating the second film 22 and the third film 23, the first conductive circuit pattern 15 and the second conductive circuit pattern 16 are also subjected to surface roughening treatment.

Certainly, the third circuit substrate 130 may not be formed, or one or more than two third circuit substrates 130 may be formed according to the requirement of the number of circuit board layers to be formed.

The fifth step, please refer to FIG. 6 , provides the first copper foil sheet 28 and the second copper foil sheet 29, and stacks and presses the second copper foil sheet 29, one of the third circuit substrates 130, and one of the The first circuit substrate 110, the third circuit substrate 130, the second circuit substrate 120 and the first copper foil sheet 28 are integrated into a whole. In the whole, the first copper foil 28 and the second copper foil 29 are respectively the outermost conductive layers on both sides of the whole, and the second film 22 or the second film is passed between the adjacent insulating layers 11. The three films 23 are bonded together, and adjacent insulating layers 11 and copper foils are bonded together through the first film 17 or the second film 22 or the third film. Specifically, the second copper foil 29 is directly bonded to the second film 22 of the third circuit substrate 130, and the first circuit substrate 110 is directly bonded to the second copper foil 29. The third film 23 of the third circuit substrate 130 is directly bonded, and the other third circuit substrate 130 is located between the first circuit substrate 110 and the first copper foil 28, and is directly connected to the first circuit substrate 110. Bonding, the second circuit substrate 120 is located between the third circuit substrate 130 far away from the second copper foil 29 and the first copper foil 28, the first copper foil 28 and the first copper foil The first film 17 of the two circuit substrates 120 is bonded together.

After aligning and stacking the second copper foil sheet 29, one of the third circuit substrates 130, one of the first circuit substrates 110, another of the third circuit substrates 130, one of the second circuit substrates 120 and When the first copper foil sheet 28 is used, it should ensure that the third circuit substrate 130, one of the first circuit substrate 110, the other third circuit substrate 130, and one of the second circuit substrate 120 Precise alignment. In actual operation, during the stacking process, the third circuit substrate 130, one of the first circuit substrate 110, the other third circuit substrate 130, and one of the second circuit substrate 120 can be Alignment holes are respectively provided, and a jig with positioning pins corresponding to the alignment holes is used for alignment.

In this embodiment, since the opposite two surfaces of each third circuit substrate 130 have the second film 22 and the third film 23 respectively, the second circuit substrate 120 and the second copper foil 29 are The adjacent surface has a first film 17, because the semi-cured material has a certain fluidity when heated, after the pressing process, one of the third circuit substrates 130, one of the first circuit substrates 110, and the other of the third circuit substrates Each of the first conductive circuit patterns 15 and the second conductive circuit patterns 16 of the circuit substrate 130 and a second circuit substrate 120 are correspondingly embedded in the insulation formed by the first film 17, the second film 22 and the third film 23. In the layer, the second copper foil sheet 29 is bonded to the second film 22 of the third circuit substrate 130, and the first copper foil sheet 28 is bonded to the first film 17 of the second circuit substrate 120. Sticky, so that the layers are tightly bonded.

The sixth step, please refer to FIG. 7 , is to fabricate the second copper foil 29 to form the third conductive circuit pattern 30 , and to fabricate the first copper foil 28 to form the fourth conductive circuit pattern 31 .

The third conductive circuit pattern 30 and the fourth conductive circuit pattern 31 can be formed by image transfer process and etching process.

In the seventh step, please refer to FIG. 8, a first solder resist layer 32 is formed on the surface of the third conductive circuit pattern 30, and a second solder resist layer 33 is formed on the surface of the fourth conductive circuit pattern 31 to obtain ten layers Circuit board 100.

The first solder resist layer 32 and the second solder resist layer 33 can be formed by printing solder resist ink. The first solder resist layer 32 is used to protect the third conductive circuit pattern 30 , and the second solder resist layer 33 is used to protect the fourth conductive circuit pattern 31 .

It can be understood that the method for manufacturing a circuit board provided by the technical solution can also be applied to the manufacture of multilayer circuit boards with other layers. Wherein, when making a multilayer circuit board, one, two or three types of circuit substrates of the first circuit substrate 110, the second circuit substrate 120 and the third circuit substrate 130 can be selected for combination, each The number can be one or more. Of course, one of the first copper foils 28 can also be selected, or a first copper foil 28 and a second copper foil 29 can be selected for combination. For details, please refer to the following method conduct:

Method 1: This method is used to form a 2N-layer circuit board, where N is a natural number greater than or equal to 4. Specifically: first, M first circuit substrates 110 (M is a natural number greater than or equal to 2, and N is greater than 2M-1), M-1 third circuit substrates 130, (N-2M+1) The two circuit substrates 120 are aligned and stacked into a laminated substrate, and the two first circuit substrates 110 are respectively located on the outermost two sides of the laminated substrate, or one first circuit substrate 110 and one second circuit substrate 120 are respectively located on the outermost two sides of the laminated substrate, or two second circuit substrates 120 are respectively located on the outermost sides of the laminated substrate, and there are first film 17, second film 17 between adjacent insulating layers 11 The second film 22 or the third film 23; secondly, a 2N-layer circuit board is obtained after one-time pressing of the laminated substrates. In the 2N-layer circuit board, two first circuit substrates 110 are located on the outermost sides of the 2N-layer circuit board, or one first circuit substrate 110 and one second circuit substrate 120 are respectively located on the 2N-layer circuit board. The outermost sides of the board, or the two second circuit substrates 120 are respectively located on the outermost sides of the 2N layer circuit board, and the first film 17, the second film 22 or the first film 17 are passed between the adjacent insulating layers 11. The three filmstrips 23 are bonded together. For the lamination method of the lamination substrates, reference may be made to the following examples:

The second embodiment: in this embodiment, M is a natural number greater than or equal to 2, and N is greater than 2M-1) The laminated substrate can be formed by the following method: first, one of the M first circuit substrates 110 The first circuit substrate 110 is used as the outermost circuit substrate; secondly, in the remaining M-1 first circuit substrates 110 and M-1 third circuit substrates 130, a third circuit substrate 130 and a first circuit substrate The substrates 110 are stacked to form a first stacking unit with only two circuit substrates, thereby obtaining M-1 first stacking units; then, N-2M+1 second circuit substrates 120 are stacked to form a second circuit substrate only The second stacking unit of the substrate 120, the second stacking unit may include one or more second circuit substrates 120; finally, M-1 stacking units of the first stacking unit and the second stacking unit are stacked as the final on the first circuit substrate 110 of the outer layer circuit substrate, and make the third circuit substrate 130 in each first stacking unit closer to the outermost circuit substrate 110 than the first circuit substrate 110 in the corresponding first stacking unit. The first circuit substrate 110, so that the first film 17 of each of the second circuit substrates 120 in the second stacking unit is closer to the second conductive circuit pattern 16 of the corresponding second circuit substrate 120 as the outermost layer The first circuit substrate 110 of the circuit substrate, thereby obtaining the stacked substrate.

Certainly, there are multiple ways of stacking M-1 first stacking units and one second stacking unit, specifically: the second stacking unit may be located adjacent to the first stacking unit and the second stacking unit. between the first circuit substrates 110 as the outermost circuit substrate; the second stacking unit can also be located between two adjacent first stacking units; the second stacking unit can also be located at a distance as The first circuit substrate 110 of the outermost circuit substrate is on the farthest first circuit substrate 110 of the first stacking unit.

When adding or subtracting layers to the multilayer circuit board in this embodiment, it is only necessary to increase or decrease the number of the first stacking units in the laminated substrate; or to increase or decrease the number of stacked units in the laminated substrate The quantity of the second stacking unit may be reduced; or the quantity of the second circuit substrate 120 in the second stacking unit may be increased or decreased in the laminated substrate.

Those skilled in the art can understand that when adding layers or reducing layers to the multilayer circuit board in this embodiment, it can also be used as the outermost circuit substrate of the laminated substrate of the multilayer circuit board formed in this embodiment. One or more second circuit substrates 120 are superimposed on the first circuit substrate 110, thereby obtaining a new multilayer circuit board, in the new multilayer circuit board, a first circuit substrate 110 and a second circuit substrate 120 They are the outermost circuit substrates on both sides of the new multilayer circuit board, or the two second circuit substrates 120 are the outermost circuit substrates on both sides of the new multilayer circuit board.

Referring to FIG. 9 , this embodiment will be described below by taking the structure of a fourteen-layer circuit board 200 obtained by a stacking method of the second embodiment when N=7 and M=3 as an example. The fourteen-layer circuit board 200 is formed by aligning and laminating three first circuit substrates 110, two third circuit substrates 130, and two second circuit substrates 120 into a laminated substrate, and pressing the laminated substrate at one time. After the substrate is formed. In the fourteen-layer circuit board 200, two first circuit substrates 110 are respectively located on the outermost two sides of the fourteen-layer circuit board 200, and the first film 17, the second The film 22 or the third film 23 are glued together. Specifically, the laminated substrate of the fourteen-layer circuit board 200 can be formed by the following method: first, one first circuit substrate 110 is used as the outermost circuit substrate of the laminated substrate, and the remaining two first circuit substrates Among the substrate 110 and the two third circuit substrates 130, one first circuit substrate 110 and one third circuit substrate 130 are stacked to form a first stacking unit, thereby obtaining two first stacking units, and two second The circuit substrates 120 are stacked to form a second stacking unit; secondly, one of the second circuit substrates 120 in the second stacking unit is directly attached to the first circuit substrate 110 as the outermost circuit substrate, and the two second circuit substrates A stacking unit is sequentially stacked on the second circuit substrate 120 farthest from the first circuit substrate 110 as the outermost circuit substrate, so that the third circuit substrate 130 in each first stacking unit is smaller than that of the corresponding first stacking unit. The first circuit substrate 110 in the unit is close to the first circuit substrate 110 as the outermost circuit substrate, and the first film 17 of each second circuit substrate 120 is smaller than the second conductive circuit of the corresponding second circuit substrate 120 The patterns 16 are all close to the first circuit substrate 110 which is the outermost circuit substrate, so as to obtain the laminated substrate.

The third embodiment: in this embodiment, M is a natural number greater than or equal to 2, and N=3M-2) The laminated substrate can be formed by the following method: first, one of the M first circuit substrates 110 The first circuit substrate 110 is used as the outermost circuit substrate; secondly, in the remaining M-1 first circuit substrates 110, M-1 second circuit substrates 120 and M-1 third circuit substrates 130, one The first circuit substrate 110, one second circuit substrate 120 and one third circuit substrate 130 are stacked to form a third stacked unit with only three circuit substrates, thereby obtaining (M-1) third stacked units; finally, the M - 1 third stacking unit is stacked on the first circuit substrate 110 as the outermost circuit substrate, and the third circuit substrate 130 in each third stacking unit is larger than that in the corresponding third stacking unit The first circuit substrate 110 is close to the first circuit substrate 110 as the outermost circuit substrate, thereby obtaining the laminated substrate.

Of course, there are many ways to stack the three circuit substrates in the third stacking unit, specifically, in each third stacking unit, the third circuit substrate 130 is arranged on the adjacent first circuit Between the substrate 110 and the second circuit substrate 120, at this time, in the formed laminated substrate, the second circuit substrate 120 in each third stacking unit is closer to the third circuit substrate 130 in the corresponding third stacking unit The first circuit substrate 110 as the outermost circuit substrate; or in each third stacking unit, the first circuit substrate 110 is arranged between the adjacent third circuit substrate 130 and the second circuit substrate 120, At this time, in the formed stacked substrate, the third circuit substrate 130 in each third stacking unit is closer to the first circuit substrate as the outermost circuit substrate than the second circuit substrate 120 in the corresponding third stacking unit. 110; or in each third stacking unit, the second circuit substrate 120 in the third stacking unit is arranged between the adjacent third circuit substrate 130 and the first circuit substrate 110, at this time, the formed In the laminated substrate, the first circuit substrate 110 is directly attached to the first film 17, and the third circuit substrate 130 in each third stacking unit is higher than the second circuit substrate 130 in the corresponding third stacking unit. The substrate 120 is close to the first circuit substrate 110 as the outermost circuit substrate.

When adding or subtracting layers to the multilayer circuit board in this embodiment, it is only necessary to increase or decrease the number of the third stacking units in the laminated substrate.

Those skilled in the art can understand that when adding or subtracting layers to the multilayer circuit board in this embodiment, one or more second stacks as in the second embodiment can also be added to the laminated substrate. unit, the number of the second circuit substrate 120 in the second stacking unit may be one or more, and the second stacking unit may be located adjacent to the third stacking unit and the outermost layer Between the first circuit substrates 110 of the circuit substrates, it may also be located between two adjacent third stacking units, or it may be stacked on the third stack unit farthest from the first circuit substrate 110 as the outermost circuit substrate. on stacked units. Those skilled in the art can also understand that when adding or subtracting layers to the multilayer circuit board in this embodiment, one or more first stacked units. Those skilled in the art can also understand that when adding or subtracting layers to the multilayer circuit board in this embodiment, the first stacking unit and Second stack unit.

In addition, those skilled in the art can also understand that when adding or reducing layers to the multilayer circuit board in this embodiment, the laminated substrate of the multilayer circuit board formed in this embodiment can also be used as the outermost On the first circuit substrate 110 of the layer circuit substrate or on the first circuit substrate 110 as the outermost layer circuit substrate of the laminated substrate of the multilayer circuit board formed after the above-mentioned build-up in this embodiment, one or more first circuit substrates 110 are superimposed Two circuit substrates 120, so as to obtain a new multilayer circuit board, in the new multilayer circuit board, a first circuit substrate 110 and a second circuit substrate 120 are respectively the two sides of the new multilayer circuit board The outermost circuit substrates, or the two second circuit substrates 120 are respectively the outermost circuit substrates on both sides of the new multilayer circuit board.

Referring to FIG. 10 , this embodiment will be described below by taking the structure of a fourteen-layer circuit board 210 obtained by a stacking method of the third embodiment when N=7 and M=3 as an example. The fourteen-layer circuit board 210 is formed by aligning and laminating three first circuit substrates 110, two third circuit substrates 130, and two second circuit substrates 120 into a laminated substrate, and pressing the laminated substrate at one time. After the substrate is formed. In the fourteen-layer circuit board 210, a first circuit substrate 110 and a second circuit substrate 120 are respectively located on the outermost two sides of the fourteen-layer circuit board 210, and the adjacent insulating layers 11 pass through the first A film 17, a second film 22 or a third film 23 are glued together. Specifically, the laminated substrate of the fourteen-layer circuit board 210 can be formed by the following method: a second circuit substrate 120, a third circuit substrate 130 and a first circuit substrate 110 are sequentially stacked to form a circuit board with only three circuits. The third stacking unit of the substrate, so that the first circuit substrate 110 in the third stacking unit is located between the adjacent third circuit substrate 130 and the second circuit substrate 120, and the two third stacking units are arranged circularly and Stacked on the first circuit substrate 110 as the outermost circuit substrate, and make the third circuit substrate 130 in each third stacking unit closer to the second circuit substrate 120 in the corresponding third stacking unit as the outermost layer The first circuit substrate 110 of the circuit substrate, so as to obtain the laminated substrate.

Method 2: This method is used to form a 2N+1 layer circuit board, where N is a natural number greater than or equal to 3. Specifically: first, align M first circuit substrates 110 (M is a natural number, and N is greater than 2M), M third circuit substrates 130 , N-2M second circuit substrates 120 and a first copper foil 28 And stacked into a laminated substrate, and the first copper foil 28 is located on the outermost side of the laminated substrate, the first circuit substrate 110 or the second circuit substrate 120 is located on the laminated substrate The other outermost side of the substrate, and there is a first film 17, a second film 22 or a third film 23 between adjacent insulating layers 11, and there is a second film between adjacent insulating layers 11 and first copper foil 28. A film 17 or a second film 22; secondly, a 2N+1-layer circuit substrate is obtained after one-time pressing of the laminated substrate, and in the 2N+1-layer circuit substrate, the first copper foil 28 is located on the The outermost side of the 2N+1 layer circuit substrate, the first circuit substrate 110 or the second circuit substrate 120 is located on the other outermost side of the 2N+1 layer circuit substrate, and the adjacent insulating layer 11 are bonded together by the first film 17, the second film 22 or the third film 23, and the adjacent insulating layers 11 and the first copper foil 28 are bonded by the first film 17 or the second film 22 Together; finally, the first copper foil 28 of the above-mentioned 2N+1-layer circuit substrate is selectively etched to form a conductive circuit pattern, that is, a 2N+1-layer circuit board is obtained. For the lamination method of the lamination substrates, reference may be made to the following examples:

Fourth Embodiment: In this embodiment, M is a natural number greater than or equal to 1, and N is greater than 2M. The laminated substrate can be formed by the following method: first, a third circuit substrate 130 and a first circuit substrate 110 to form a first stacking unit with only two circuit substrates, thereby obtaining M first stacking units; secondly, stacking N-2M second circuit substrates 120 to form a second stacking unit; finally, The M first stacking units and the second stacking units are stacked on the first copper foil sheet 28, and the third circuit substrate 130 in each first stacking unit is compared with the corresponding first stacking unit. The first circuit substrate 110 in the stack is close to the first copper foil sheet 28, and the first film 17 of each second circuit substrate 120 in the second stacking unit is smaller than the second film 17 of the corresponding second circuit substrate 120. The conductive circuit patterns 16 are all close to the first copper foil 28, so as to obtain the laminated substrate.

Of course, there are many ways to stack the M first stacking units and one second stacking unit. Specifically, the second stacking unit can be located adjacent to the first stacking unit and the second stacking unit. between a copper foil sheet 28; the second stacking unit can also be located between two adjacent first stacking units; the second stacking unit can also be stacked at a distance from the first copper foil sheet 28 on the first circuit substrate 110 of the furthest first stack unit.

When adding or subtracting layers to the multilayer circuit board in this embodiment, it is only necessary to increase or decrease the number of the first stacking units in the laminated substrate; or to increase or decrease the number of stacked units in the laminated substrate The quantity of the second stacking unit may be reduced; or the quantity of the second circuit substrate 120 in the second stacking unit may be increased or decreased in the laminated substrate.

Referring to FIG. 11 , this embodiment will be described below by taking the structure of the thirteen-layer circuit substrate 220 obtained by a stacking method of the fourth embodiment when N=6 and M=3 as an example. The thirteen-layer circuit substrate 220 is formed by aligning and stacking two first circuit substrates 110, two third circuit substrates 130, two second circuit substrates 120 and a first copper foil 28 into a composite substrate, And it is formed after pressing the laminated substrates together. In the thirteen-layer circuit substrate 220, the first copper foil 28 is located on the outermost side of the thirteen-layer circuit substrate 220, and the second circuit substrate 120 is the outermost side of the thirteen-layer circuit substrate 220. The outermost other side, and the adjacent insulating layers 11 are bonded together by the first film 17, the second film 22 or the third film 23, and the adjacent insulating layers 11 and the first copper foil 28 are bonded together. Bonded together by the third film 23. Specifically, the stacked substrate of the thirteen-layer circuit substrate 220 can be formed by the following method: stacking a first circuit substrate 110 and a third circuit substrate 130 to form a first stacking unit, thereby obtaining two first stacked unit, stacking two second circuit substrates 120 to form a second stacking unit; stacking two of the first stacking units on the first copper foil in turn, so that the third circuit in each first stacking unit The substrates 130 are closer to the first copper foil sheet 28 than the first circuit substrate 110 in the corresponding first stacking unit, and the second stacking unit is stacked on the first stacking unit farthest from the first copper foil sheet 28 on the first circuit substrate 110, and the first film 17 of each second circuit substrate 120 is closer to the first copper foil 28 than the second conductive circuit pattern 16 of the corresponding second circuit substrate 120, Thus, the laminated substrate was obtained.

Embodiment 5: In this embodiment, M is a natural number greater than or equal to 1, and N=3M. The laminated substrate can be formed by the following method: a first circuit substrate 110, a second circuit substrate 120 and A third circuit substrate 130 is stacked into a third stacking unit with only three circuit substrates, thereby forming M third stacking units; stacking the M third stacking units on the first copper foil sheet 28, Moreover, the third circuit substrate 130 in each third stacking unit is closer to the first copper foil sheet 28 than the first circuit substrate 110 in the corresponding third stacking unit, so as to obtain the stacked substrate.

Of course, there are many ways to stack the three circuit substrates in the third stacking unit, specifically, in each third stacking unit, the third circuit substrate 130 is arranged on the adjacent first circuit Between the substrate 110 and the second circuit substrate 120, at this time, in the formed laminated substrate, the second circuit substrate 120 in each third stacking unit is closer to the third circuit substrate 130 in the corresponding third stacking unit The first copper foil sheet 28; or in each third stacking unit, the first circuit substrate 110 is arranged between the adjacent third circuit substrate 130 and the second circuit substrate 120, at this time, the In the formed laminated substrate, the third circuit substrate 130 in each third stacking unit is closer to the first copper foil sheet 28 than the second circuit substrate 120 in the corresponding third stacking unit; or in each third stacking unit In the lamination unit, the second circuit substrate 120 is arranged between the adjacent third circuit substrate 130 and the first circuit substrate 110. At this time, in the formed lamination substrate, the first circuit substrate 110 and the first circuit substrate 110 are The first film 17 is directly attached to each other, and the third circuit substrate 130 in each third stacking unit is closer to the first copper foil 28 than the second circuit substrate in the corresponding third stacking unit.

When adding or subtracting layers to the multilayer circuit board in this embodiment, it is only necessary to increase or decrease the number of the third stacking units in the laminated substrate.

Those skilled in the art can understand that when adding or subtracting layers to the multilayer circuit board in this embodiment, one or more second stacks as in the second embodiment can also be added to the laminated substrate. unit, the number of the second circuit substrate 120 in the second stacking unit may be one or more, wherein the second stacking unit may be located adjacent to the third stacking unit and the first The copper foil sheets 28 may also be located between two adjacent third stacking units, or may be stacked on the third stacking unit farthest from the first copper foil sheet 28 . Those skilled in the art can also understand that when adding or subtracting layers to the multilayer circuit board in this embodiment, one or more first stacked units. Those skilled in the art can also understand that when adding or subtracting layers to the multilayer circuit board in this embodiment, the first stacking unit and Second stack unit.

Referring to FIG. 12 , the present embodiment will be described below by taking the structure of the thirteen-layer circuit substrate 230 obtained by a stacking method of the fifth embodiment when N=6 and M=2 as an example. The thirteen-layer circuit substrate 230 is formed by aligning and stacking two first circuit substrates 110, two third circuit substrates 130, two second circuit substrates 120 and a first copper foil 28 into a composite substrate, And it is formed after pressing the laminated substrates together. In the thirteen-layer circuit board 230, the first copper foil 28 is located on the outermost side of the thirteen-layer circuit board 230, and a first circuit board 110 is the outermost side of the thirteen-layer circuit board 230. The other side of the outer side, and the adjacent insulating layers 11 are bonded together by the first film 17, the second film 22 or the third film 23, and the adjacent insulating layers 11 and the first copper foil 28 are bonded together by The first films 17 are glued together. Specifically, the laminated substrate of the thirteen-layer circuit substrate 230 can be formed by the following method: a second circuit substrate 120, a third circuit substrate 130 and a first circuit substrate 110 are stacked in sequence to form a circuit board with only three circuits. The third stacking unit of the substrate, the third circuit substrate 130 in the third stacking unit is located between the first circuit substrate 110 and the second circuit substrate 120, and the two third stacking units are arranged circularly and stacked on the on the first copper foil sheet 28, and make the second circuit substrate 120 in each third stacking unit closer to the first copper foil sheet 28 than the third circuit substrate 130 in the corresponding third stacking unit, so that The laminated substrate was obtained.

Method 3: This method is used to form a 2N+2-layer circuit board, and N is a natural number greater than or equal to 4. Specifically: first, M first circuit substrates 110 (M is a natural number, and N is greater than 2M+1), M+1 third circuit substrates 130, N-2M-1 second circuit substrates 120, a first A copper foil sheet 28 and a second copper foil sheet 29 are aligned and stacked into a laminated substrate, and the first copper foil sheet 28 and the second copper foil sheet 29 are respectively located on the outermost two sides of the laminated substrate. The side layer conductive layer, and the first film 17, the second film 22 or the third film 23 are arranged between the adjacent insulating layers 11, and the adjacent insulating layers 11 and the first copper foil 28 and the adjacent insulating layers There is a first film 17 or a second film 22 or a third film between the layer 11 and the second copper foil 29; secondly, a 2N+2-layer circuit substrate is obtained after one-time pressing of the laminated substrate, and the In the 2N+2-layer circuit substrate, the first copper foil 28 and the second copper foil 29 are respectively located on the outermost two sides of the 2N+2-layer circuit substrate, and between adjacent insulating layers 11 Bonded together by the first film 17, the second film 22 or the third film 23, between the adjacent insulating layer 11 and the first copper foil sheet 28 and between the adjacent insulating layer 11 and the second copper foil sheet 29 Both are bonded together by the first film 17 or the second film 22 or the third film 23; finally, the first copper foil sheet 28 and the second copper foil sheet 29 of the above-mentioned 2N+2 layer circuit substrate are respectively passed through Selective etching forms a conductive circuit pattern, that is, a 2N+2 layer circuit board is obtained. For the lamination method of the lamination substrates, reference may be made to the following examples:

Embodiment 6: In this embodiment, M is a natural number greater than or equal to 1, and N is greater than 2M+1. The laminated substrate can be formed by the following method: first, a third circuit substrate 130 and a first The circuit substrates 110 are stacked into a first stacking unit with only two circuit substrates, thereby forming M first stacking units; secondly, stacking N-2M-1 second circuit substrates 120 to form a second stacking unit ; Finally, the remaining one third circuit substrate 130, M first stacking units and one second stacking unit are stacked between the first copper foil sheet 28 and the second copper foil sheet 29, so as to The remaining third circuit substrate 130 is directly attached to the second copper foil sheet 29, and the third circuit substrate 130 in each first stacking unit is smaller than the first circuit in the corresponding first stacking unit. The substrate 110 is close to the first copper foil 28, and the first film 17 of each second circuit substrate 120 is closer to the first copper foil than the second conductive circuit pattern 16 of the corresponding second circuit substrate 120. 28, thereby obtaining the laminated substrate.

Of course, there are many ways to stack the M first stacking units and one second stacking unit. Specifically, the second stacking unit can be located adjacent to the first stacking unit and the second stacking unit. between a copper foil sheet 28; the second stacking unit can also be located between two adjacent first stacking units; the second stacking unit can also be located at the distance from the first copper foil sheet 28 on the first circuit substrate 110 of the remote first stack unit.

When adding or subtracting layers to the multilayer circuit board in this embodiment, it is only necessary to increase or decrease the number of the first stacking units in the laminated substrate; or to increase or decrease the number of stacked units in the laminated substrate The quantity of the second stacking unit may be reduced; or the quantity of the second circuit substrate 120 in the second stacking unit may be increased or decreased in the laminated substrate.

Referring to FIG. 13 , this embodiment will be described below by taking the structure of a sixteen-layer circuit substrate 240 obtained by a stacking method of the sixth embodiment when N=7 and M=3 as an example. The sixteen-layer circuit substrate 240 is formed by aligning two first circuit substrates 110, three third circuit substrates 130, two second circuit substrates 120, a first copper foil 28 and a second copper foil 29. and laminated to form a laminated substrate, which is formed after pressing the laminated substrate once. In the sixteen-layer circuit substrate 240, the first copper foil sheet 28 and the second copper foil sheet 29 are respectively located on the outermost two sides of the sixteen-layer circuit substrate, and adjacent insulating layers 11 pass through The first film 17, the second film 22 or the third film 23 are bonded together, and the adjacent insulating layer 11 and the first copper foil sheet 28 and the adjacent insulating layer 11 and the second copper foil sheet 29 are all passed through The first film 17 or the second film 22 or the third film 23 are glued together. Specifically, the stacked substrate of the sixteen-layer circuit substrate 240 can be formed by the following method: stacking a first circuit substrate 110 and a third circuit substrate 130 to form a first stacking unit, thereby obtaining two first stacked unit, two second circuit substrates 120 are stacked to form a second stacking unit; the remaining one third circuit substrate 130, M first stacking units, and one second stacking unit are stacked on the first between the copper foil sheet 28 and the second copper foil sheet 29, and make the remaining third circuit substrate 130 directly adhere to the second copper foil sheet 29, one of the second stacking units The second circuit substrate 120 is directly attached to the first copper foil sheet 28, and the first film 17 of each second circuit substrate 120 is closer to the second conductive circuit pattern 16 of the corresponding second circuit substrate 120. For the first copper foil sheet, two first stacking units are sequentially stacked on the second circuit substrate 120 farthest from the first copper foil sheet 28, and the third circuit substrate 130 in each first stacking unit All are closer to the first copper foil 28 than the first circuit substrate 110 in the corresponding first stacking unit, so as to obtain the laminated substrate.

The seventh embodiment: in this embodiment, M is a natural number greater than or equal to 1, and N=3M+1, the laminated substrate can be formed by the following method: first, a first circuit substrate 110, a second The circuit substrate 120 and a third circuit substrate 130 are stacked into a third stacking unit with only three circuit substrates, thereby forming M third stacking units; secondly, the remaining third circuit substrate 130, M said first stacking units Three stacking units are stacked between the first copper foil sheet 28 and the second copper foil sheet 29, and the remaining third circuit substrate 130 is directly attached to the second copper foil sheet 29, M The third stacking unit is stacked between the first copper foil sheet 28 and the remaining third circuit substrate 130, so that the third circuit substrate 130 in each third stacking unit is smaller than the corresponding The first circuit substrate 110 in the third stacking unit is close to the first copper foil sheet 28, so as to obtain the stacked substrate.

Of course, there are many ways to stack the three circuit substrates in the third stacking unit, specifically: in each of the third stacking units, the third circuit substrate 130 is arranged on the adjacent first Between the first circuit substrate 110 and the second circuit substrate 120, at this time, in the formed laminated substrate, the second circuit substrate 120 in each third stacking unit is higher than the third circuit substrate 120 in the corresponding third stacking unit 130 is close to the first copper foil sheet 28; or in each of the third stacking units, the first circuit substrate 110 is disposed between the adjacent third circuit substrate 130 and the second circuit substrate 120, this , in the formed laminated substrate, the third circuit substrate 130 in each third stacking unit is closer to the first copper foil 28 than the second circuit substrate 120 in the corresponding third stacking unit; or in each In each of the third stacking units, the second circuit substrate 120 is disposed between the adjacent third circuit substrate 130 and the first circuit substrate 110, at this time, in the formed laminated substrate, each third stack The third circuit substrate 130 in the unit is closer to the first copper foil 28 than the corresponding second circuit substrate 120 .

When adding or subtracting layers to the multilayer circuit board in this embodiment, it is only necessary to increase or decrease the number of the third stacking units in the laminated substrate.

Those skilled in the art can understand that when adding or subtracting layers to the multilayer circuit board in this embodiment, one or more second stacks as in the second embodiment can also be added to the laminated substrate. unit, the number of the second circuit substrate 120 of the second stacking unit may be one or more, and the second stacking unit may be located adjacent to the third stacking unit and the first copper foil 28, the second stacking unit may also be located between two adjacent third stacking units, and the second stacking unit may also be located in the third farthest from the first copper foil 28 Between the stacking unit and the remaining third circuit substrate 130 , the second stacking unit may also be located between the second copper foil sheet 29 and the remaining third circuit substrate 130 . Those skilled in the art can also understand that when adding or subtracting layers to the multilayer circuit board in this embodiment, one or more first in stacked units. Those skilled in the art can also understand that when adding or subtracting layers to the multilayer circuit board in this embodiment, it is also possible to simultaneously add the stacking element in the first stacking unit in the second embodiment to the laminated substrate. and the second stack unit.

Referring to FIG. 14 , this embodiment will be described below by taking the structure of a sixteen-layer circuit substrate 250 obtained by a stacking method of the seventh embodiment when N=7 and M=2 as an example. The sixteen-layer circuit substrate 250 is aligned by aligning two first circuit substrates 110, three third circuit substrates 130, two second circuit substrates 120, a first copper foil 28 and a second copper foil 29. and laminated to form a laminated substrate, which is formed after pressing the laminated substrate once. In the sixteen-layer circuit substrate 250, the first copper foil sheet 28 and the second copper foil sheet 29 are respectively located on the outermost two sides of the sixteen-layer circuit substrate, and the adjacent insulating layers 11 pass through The first film 17, the second film 22 or the third film 23 are bonded together, between the adjacent insulating layer 11 and the first copper foil sheet 28 and between the adjacent insulating layer 11 and the second copper foil sheet 29 They are all bonded together by the second film 22 or the third film. Specifically, the laminated substrate of the sixteen-layer circuit substrate 250 can be formed by the following method: a second circuit substrate 120, a third circuit substrate 130 and a first circuit substrate 110 are sequentially stacked to form a circuit board with only three circuits. The third stacking unit of the substrate, so that in each of the third stacking units, the first circuit substrate 110 is located between the adjacent second circuit substrate 120 and the third circuit substrate 130; Three circuit substrates 130 and two first stacking units are stacked between the first copper foil sheet 28 and the second copper foil sheet 29, so that the remaining third circuit substrate 130 and the second copper foil sheet The foils 29 are directly attached to each other, so that two third stacking units are arranged circularly and stacked between the first copper foil 28 and the remaining third circuit substrate 130, and each third stacking unit The third circuit substrate 130 in the unit is closer to the first copper foil sheet 28 than the second circuit substrate 120 in the corresponding third stacked unit, so as to obtain the laminated substrate.

Method 3: This method is used to form a 2N+2-layer circuit board, and N is a natural number greater than or equal to 1. Specifically: align and laminate N second circuit substrates 120 and one first circuit substrate 110 into a laminated substrate, so that the first film 17 of each second circuit substrate 120 is smaller than the second conductive circuit pattern 16 Closer to the first circuit substrate 110, a 2N+2-layer circuit substrate is obtained after one-time pressing of the laminated substrate, that is, a 2N+2-layer circuit board is obtained. In the 2N+2 layer circuit board, the adjacent insulating layers 11 are bonded together by the first adhesive film 17 .

Certainly, there are various ways of stacking the N second circuit substrates 120 and one first circuit substrate 110 , specifically, the first circuit substrate 110 is arranged between two adjacent second circuit substrates 120 , and the first film 17 of each second circuit substrate 120 is closer to the first circuit substrate 110 than the second conductive circuit pattern 16; or the first circuit substrate 110 is used as the laminated substrate The outermost circuit substrate, N second circuit substrates 120 are stacked on one side of the first circuit substrate 110 in sequence.

When adding or subtracting layers to the multilayer circuit board in this embodiment, it is only necessary to increase or decrease the number of the second circuit substrates 120 in the laminated substrate.

For the eighth embodiment, please refer to FIG. 15 , and the structure of the eight-layer circuit board 260 obtained through the third method when N=3 is taken as an example to describe this embodiment. The eight-layer circuit board 260 can be formed by the following method: First, align and stack one first circuit substrate 110 and three second circuit substrates 120 into a laminated substrate, so that the first circuit substrate 110 is positioned on the The outermost side of the laminated substrates, and the first film 17 of each of the second circuit substrates 120 is closer to the first circuit substrate 110 than the second conductive circuit pattern 16; The eight-layer circuit board 260 can be obtained by combining the substrates.

Of course, it is not limited to the arrangement of the above method 1 to method 3.

It can be understood that the laminated substrates formed by the above methods 1 to 3 may also include conductive circuits exposed from both sides after lamination The step of forming a solder mask on the pattern surface.

The multilayer circuit board manufacturing method provided by this technical solution is to manufacture multiple circuit substrates at the same time, and then form a film on one or both surfaces of some circuit substrates by bonding, and form a through hole in the film and form a conductive material . In this way, the copper foil, the circuit substrate bonded with the film and the conductive material, and the circuit substrate not bonded with the film are stacked as needed, so that a multilayer circuit board can be obtained by one pressing. Since a plurality of circuit boards can be produced simultaneously, the time for circuit board production can be shortened. Since each circuit substrate is manufactured separately, compared with the method of layer-by-layer stacking in the prior art, the yield rate of circuit board production can be improved.

It can be understood that those skilled in the art can make various other corresponding changes and modifications according to the technical concept of the present invention, and all these changes and modifications should belong to the protection scope of the claims of the present invention.

Claims (24)

1. A method for making a multilayer circuit board, comprising the steps of: Provide N copper-clad substrates, wherein N is a natural number greater than or equal to 4, and each of the copper-clad substrates includes an insulating layer and a first copper foil layer and a second copper foil attached to the opposite sides of the insulating layer layer; making the first copper foil layer of each of the copper-clad substrates to form a first conductive circuit pattern, making the second copper foil layer of each of the copper-clad substrates to form a second conductive circuit pattern, and the first conductive The circuit pattern and the second conductive circuit pattern are electrically connected to each other through at least one conductive hole, so that the N copper-clad substrates are made into N first circuit substrates; Take N-2M+1 first circuit substrates among the N first circuit substrates, where M is a natural number greater than or equal to 2, and N is greater than 2M-1, and among the N-2M+1 first circuit substrates Each of the first conductive circuit patterns in the first circuit substrate in a circuit substrate is pasted with a first film, and the first film has at least one first through hole, and the at least one first through hole The first conductive material is filled inside, and the first conductive material is electrically connected to the adjacent first conductive circuit pattern, so that N-2M+1 first circuit substrates are made into N-2M+1 second circuit substrates ; Take M-1 first circuit substrates among the N first circuit substrates, and attach the first conductive circuit pattern on the surface of each first circuit substrate among the M-1 first circuit substrates. Two films, a third film is attached to the surface of the second conductive circuit pattern in each of the M-1 first circuit substrates, and the second film has at least one second through hole, so The third film has at least one third through hole, and the at least one second through hole is filled with a second conductive material, and the second conductive material is electrically connected to the adjacent first conductive circuit pattern, and the second conductive material is electrically connected to the adjacent first conductive circuit pattern. The at least one third through hole is filled with a third conductive material, and the third conductive material is electrically connected to the adjacent second conductive circuit pattern, so that the M-1 first circuit substrates are made into M-1 a third circuit substrate; and Pressing the remaining M first circuit substrates, the N-2M+1 second circuit substrates and the M-1 third circuit substrates at one time to form a 2N-layer circuit board, in the 2N-layer circuit board Adjacent insulating layers are bonded together by the first film, the second film or the third film, and two first circuit substrates are located on the outermost two sides of the 2N-layer circuit board, or one first The circuit substrate and one second circuit substrate are located on the outermost two sides of the 2N-layer circuit board, or two second circuit substrates are located on the outermost two sides of the 2N-layer circuit board. 2. The method for making a multilayer circuit board according to claim 1, wherein, after laminating the remaining M first circuit substrates, the N-2M+1 second circuit substrates and the M- Before forming 1 third circuit substrate to form a 2N-layer circuit board, align and stack the remaining M first circuit substrates, the N-2M+1 second circuit substrates and the M-1 third circuit substrates substrate to form a laminated substrate, and the method for forming the laminated substrate comprises the steps of: One of the M first circuit substrates is used as the outermost circuit substrate of the laminated substrate; among the remaining M-1 first circuit substrates and M-1 third circuit substrates, the A third circuit substrate and a first circuit substrate are stacked to form a first stacked unit with only two circuit substrates, thereby obtaining M-1 first stacked units; stacking N-2M+1 second circuit substrates to form a second stacking unit; M-1 first stacking units and one second stacking unit are stacked on the first circuit substrate as the outermost circuit substrate, and the third circuit substrate in each first stacking unit is The first circuit substrate in the corresponding first stacking unit is close to the first circuit substrate as the outermost circuit substrate, so that the first film of each second circuit substrate in the second stacking unit is closer to the first film of the corresponding first circuit substrate. The second conductive circuit patterns of the two circuit substrates are all close to the first circuit substrate as the outermost circuit substrate, so as to obtain the laminated substrate. 3. The manufacturing method of a multilayer circuit board according to claim 2, wherein, after M-1 first stacking units and the second stacking units are stacked on the first stacking unit as the outermost circuit substrate In the step on a circuit substrate, the second stacking unit is located between the adjacent first stacking unit and the first circuit substrate as the outermost circuit substrate, or the second stacking unit is located on the adjacent Between two adjacent first stacking units, or the second stacking unit is stacked on the first circuit substrate of the first stacking unit farthest from the first circuit substrate as the outermost circuit substrate. 4. The method for making a multilayer circuit board according to claim 1, wherein N=3M-2, after laminating the remaining M first circuit substrates and the N-2M+1 second circuits Before the substrate and the M-1 third circuit substrates are used to form a 2N-layer circuit board, align and stack the remaining M first circuit substrates, the N-2M+1 second circuit substrates, and the M -1 third circuit substrate to form a laminated substrate, the forming method of the laminated substrate comprises the steps of: Using one of the M first circuit substrates as the outermost circuit substrate; Among the remaining M-1 first circuit substrates, M-1 second circuit substrates, and M-1 third circuit substrates, stack one first circuit substrate, one second circuit substrate and one third circuit substrate forming a third stacking unit with only three circuit substrates, thereby obtaining M-1 third stacking units; M-1 third stacking units are stacked on the first circuit substrate as the outermost circuit substrate, and the third circuit substrates in each third stacking unit are compared with those in the corresponding third stacking unit. The first wiring substrate is close to the first wiring substrate as the outermost wiring substrate, thereby obtaining the laminated substrate. 5. The method for manufacturing a multilayer circuit board according to claim 4, wherein, in the third stacking unit, the third circuit substrate is arranged between adjacent first circuit substrates and second circuit substrates between, or the first circuit substrate is arranged between the adjacent third circuit substrate and the second circuit substrate, or the second circuit substrate is arranged between the adjacent third circuit substrate and the first circuit substrate . 6. The method for manufacturing a multilayer circuit board as claimed in claim 1, wherein making N-2M+1 first circuit substrates into N-2M+1 second circuit substrates comprises the steps of: On each of the first conductive circuit patterns in the N-2M+1 first circuit substrates, the first film and a release film are sequentially laminated, and on the N-2M+1 first circuit substrates A protective film is pasted on the surface of each second conductive circuit pattern in the method; Pre-pressing the first circuit substrate, the first film, the release film and the protective film, so that the first film and the first circuit substrate are bonded together, and the protective film is bonded to the first 2. On the graph of the conductive circuit; removing the release film; forming the at least one first through hole in the first film through a laser drilling process, and part of the first conductive circuit pattern is exposed from the at least one first through hole; forming a first conductive material in the at least one first through hole by printing conductive paste; and removing the protection film. 7. The method for manufacturing a multilayer circuit board as claimed in claim 1, wherein making M-1 first circuit substrates into M-1 third circuit substrates comprises the steps of: Lay the second film and a release film sequentially on each of the first conductive circuit patterns in the M-1 first circuit substrates, and each of the M-1 first circuit substrates A third film and another release film are pasted on the surface of the second conductive circuit pattern; Pre-pressing the first circuit substrate, the second film, the third film and two release films, so that the second film and the third film are bonded to both sides of the first circuit substrate; removing the two release films; The at least one second through hole is formed in the second film through a laser drilling process, part of the first conductive circuit pattern is exposed from the at least one second through hole, and the third through hole is formed through a laser drilling process. The at least one third through hole is formed in the film, and part of the second conductive circuit pattern is exposed from the at least one third through hole; and A second conductive material is formed in the at least one second through hole by printing conductive paste, and a third conductive material is formed in the at least one third through hole by printing conductive paste. 8. A method for making a multilayer circuit board, comprising the steps of: Provide N copper-clad substrates, wherein N is a natural number greater than or equal to 3, and each of the copper-clad substrates includes an insulating layer and a first copper foil layer and a second copper foil attached to the opposite sides of the insulating layer layer; making the first copper foil layer of each of the copper-clad substrates to form a first conductive circuit pattern, making the second copper foil layer of each of the copper-clad substrates to form a second conductive circuit pattern, and the first conductive The circuit pattern and the second conductive circuit pattern are electrically connected to each other through at least one conductive hole, so that the N copper-clad substrates are made into N first circuit substrates; Take N-2M first circuit substrates among the N first circuit substrates, where M is a natural number, and N is greater than 2M, and each of the first circuit substrates among the N-2M first circuit substrates The surface of the first conductive circuit pattern in the circuit substrate is pasted with a first film, the first film has at least one first through hole, and a first conductive material is filled in the first through hole, and the first conductive material and The adjacent first conductive circuit patterns are electrically connected to each other, so that the N-2M first circuit substrates are made into N-2M second circuit substrates; Take M first circuit substrates among the N first circuit substrates, attach a second film to the surface of the first conductive circuit pattern in each of the M first circuit substrates, and The surface of the second conductive circuit pattern in each of the M first circuit substrates is pasted with a third film, and the second film has at least one second through hole, and each of the third The film has at least one third through hole, and the second conductive material is filled in the at least one second through hole, and the second conductive material is electrically connected to the adjacent first conductive circuit pattern, and the at least one The third through hole is filled with a third conductive material, and the third conductive material is electrically connected to the adjacent second conductive circuit pattern, so that the M first circuit substrates are made into M third circuit substrates; The first copper foil is provided, and the remaining M first circuit substrates, N-2M second circuit substrates, M third circuit substrates, and the first copper foil are laminated at one time to form a 2N+ 1-layer circuit substrate, in the 2N+1-layer circuit substrate, adjacent insulating layers are bonded together by the first film, the second film or the third film, and the adjacent insulating layers and the first copper foil The sheets are bonded together by the first film or the second film, and the first copper foil is located on the outermost side of the 2N+1 layer circuit substrate, one of the first circuit substrate or one of the second The second circuit substrate is located on the other outermost side of the 2N+1 layer circuit substrate; and The first copper foil is selectively etched into a conductive circuit pattern to obtain a 2N+1 layer circuit board. 9. The method for making a multilayer circuit board as claimed in claim 8, wherein the remaining M first circuit substrates, the N-2M second circuit substrates, and the M first circuit substrates are bonded once. Before three circuit substrates and the first copper foil are used to form a 2N+1 layer circuit substrate, align and stack the remaining M first circuit substrates, N-2M second circuit substrates, M said The third circuit substrate and the first copper foil are used to form a laminated substrate, and the method for forming the laminated substrate includes the step of: among the remaining M first circuit substrates and M third circuit substrates, one of the first Three circuit substrates and one first circuit substrate are stacked to form a first stacked unit with only two circuit substrates, thereby obtaining M first stacked units; stacking N-2M second circuit substrates to form a second stacking unit; Stacking M first stacking units and one second stacking unit on the first copper foil, and making the third circuit substrate in each first stacking unit smaller than that in the corresponding first stacking unit The first circuit substrate is close to the first copper foil, so that the first film of each second circuit substrate in the second stacking unit is closer to the second conductive circuit pattern of the corresponding second circuit substrate the first copper foil to obtain the laminated substrate. 10. A method for manufacturing a multilayer circuit board as claimed in claim 9, wherein, after stacking the M first stacking units and the second stacking units on the first copper foil In the step, the second stacking unit is located between the adjacent first stacking unit and the first copper foil, or the second stacking unit is located between two adjacent first stacking units or the second stacking unit is stacked on the first circuit substrate of the first stacking unit farthest from the first copper foil. 11. The method for manufacturing a multilayer circuit board according to claim 8, wherein N=3M, the remaining M first circuit substrates, N-2M second circuit substrates, M Before the third circuit substrate and the first copper foil are formed to form a 2N+1 layer circuit substrate, align and stack the remaining M first circuit substrates, N-2M second circuit substrates, M pieces of the third circuit substrate and the first copper foil are used to form a laminated substrate, and the method for forming the laminated substrate includes the steps of: Among the remaining M first circuit substrates, M second circuit substrates, and M third circuit substrates, one first circuit substrate, one second circuit substrate, and one third circuit substrate are stacked to form a circuit board with only three circuits. a third stacking unit of the substrate, thereby obtaining M third stacking units; stacking M third stacking units on the first copper foil, and making the third circuit substrate in each third stacking unit closer to the first circuit substrate in the corresponding third stacking unit first copper foil, so as to obtain the laminated substrate. 12. The method for manufacturing a multilayer circuit board according to claim 11, wherein, in the third stacking unit, the third circuit substrate is arranged between adjacent first circuit substrates and second circuit substrates between, or the first circuit substrate is arranged between the adjacent third circuit substrate and the second circuit substrate, or the second circuit substrate is arranged between the adjacent third circuit substrate and the first circuit substrate . 13. The method for manufacturing a multilayer circuit board as claimed in claim 8, wherein making N-2M first circuit substrates into N-2M second circuit substrates comprises the steps of: Lay the first film and a release film sequentially on each of the first conductive circuit patterns in the N-2M first circuit substrates, and each of the N-2M first circuit substrates A protective film is pasted on the surface of the second conductive circuit pattern; Pre-pressing the first circuit substrate, the first film, the release film and the protective film, so that the first film and the first circuit substrate are bonded together, and the protective film is bonded to the first 2. On the graph of the conductive circuit; removing the release film; forming the at least one first through hole in the first film through a laser drilling process, and part of the first conductive circuit pattern is exposed from the at least one first through hole; forming a first conductive material in the at least one first through hole by printing conductive paste; and removing the protection film. 14. The method for manufacturing a multilayer circuit board as claimed in claim 8, wherein making M first circuit substrates into M third circuit substrates comprises the steps of: Lay the second film and a release film sequentially on each of the first conductive circuit patterns in the M first circuit substrates, and each second conductive circuit in the M first circuit substrates Lay a third film and another release film on the graphic surface; Pre-pressing the first circuit substrate, the second film, the third film and two release films, so that the second film and the third film are bonded to both sides of the first circuit substrate; removing the two release films; The at least one second through hole is formed in the second film through a laser drilling process, part of the first conductive circuit pattern is exposed from the at least one second through hole, and the third through hole is formed through a laser drilling process. The at least one third through hole is formed in the film, and part of the second conductive circuit pattern is exposed from the at least one third through hole; and A second conductive material is formed in the at least one second through hole by printing conductive paste, and a third conductive material is formed in the at least one third through hole by printing conductive paste. 15. A method for manufacturing a multilayer circuit board, comprising the steps of: Provide N copper-clad substrates, wherein N is a natural number greater than or equal to 3, and each of the copper-clad substrates includes an insulating layer and a first copper foil layer and a second copper foil attached to the opposite sides of the insulating layer layer; making the first copper foil layer of each of the copper-clad substrates to form a first conductive circuit pattern, making the second copper foil layer of each of the copper-clad substrates to form a second conductive circuit pattern, and the first conductive The circuit pattern and the second conductive circuit pattern are electrically connected to each other through at least one conductive hole, so that the N copper-clad substrates are made into N first circuit substrates; Take N-2M-1 first circuit substrates among the N first circuit substrates, where M is a natural number, and N is greater than 2M+1, and among the N-2M-1 first circuit substrates The surface of the first conductive circuit pattern in each of the first circuit substrates is pasted with a first film, and the first film has at least one first through hole, and the first conductive circuit is filled in the at least one first through hole. material, the first conductive material is electrically connected to the corresponding first conductive circuit pattern, so that N-2M-1 first circuit substrates are made into N-2M-1 second circuit substrates; Take M+1 first circuit substrates among the N first circuit substrates, and the surface of the first conductive circuit pattern in each of the first circuit substrates in the M+1 first circuit substrates is attached to the surface of the first circuit substrate. Two films, a third film is attached to the surface of the second conductive circuit pattern in each of the M+1 first circuit substrates, and the second film has at least one second through hole, so The third film has at least one third through hole, and the at least one second through hole is filled with a second conductive material, and the second conductive material is electrically connected to the adjacent first conductive circuit pattern, and the second conductive material is electrically connected to the adjacent first conductive circuit pattern. The at least one third through hole is filled with a third conductive material, and the third conductive material is electrically connected to the adjacent second conductive circuit pattern, so that the M+1 first circuit substrates are made into M+1 a third circuit substrate; Provide the first copper foil and the second copper foil, press the first copper foil, the remaining M first circuit substrates, N-2M-1 second circuit substrates, M+1 The third circuit substrate and the second copper foil form a 2N+2-layer circuit substrate, and in the 2N+2-layer circuit substrate, the first copper foil and the second copper foil are respectively It is located on the outermost two sides of the 2N+2-layer circuit substrate, and the adjacent insulating layers are bonded together by the first film, the second film or the third film, and the adjacent insulating layers and the first copper foil The sheets and the adjacent insulating layers and the second copper foil sheets are all bonded together by the first film or the second film or the third film; and The first copper foil and the second copper foil are respectively formed into conductive circuit patterns through selective etching, so as to obtain a 2N+2 layer circuit board. 16. The method for manufacturing a multilayer circuit board as claimed in claim 15, wherein the first copper foil sheet, the remaining M first circuit substrates, and the N-2M-1 first circuit boards are laminated once. Before the second circuit substrate, M+1 third circuit substrates, and the second copper foil sheets form a 2N+2 layer circuit substrate, align and stack the first copper foil sheets, the remaining M first A circuit substrate, N-2M-1 second circuit substrates, M+1 third circuit substrates, and the second copper foil to form a laminated substrate, and the method for forming the laminated substrate includes the steps : Among the remaining M first circuit substrates and M third circuit substrates, one third circuit substrate and one first circuit substrate are stacked to form a first stacked unit with only two circuit substrates, thereby obtaining M a stack unit; stacking N-2M-1 second circuit substrates to form a second stacking unit; Stack the remaining one third circuit substrate, M first stacking units and one second stacking unit between the first copper foil and the second copper foil, and make the remaining A third circuit substrate is directly attached to the second copper foil, so that the third circuit substrate in each first stacking unit is closer to the first circuit substrate than the first circuit substrate in the corresponding first stacking unit. Copper foil, so that the first film of each of the second circuit substrates in the second stacking unit is closer to the first copper foil than the second conductive circuit pattern of the corresponding second circuit substrate, thereby obtaining The laminated substrate. 17. The method for manufacturing a multilayer circuit board according to claim 16, characterized in that, after the remaining one third circuit substrate, M first stacking units, and one second stacking unit are stacked on the In the step between the first copper foil sheet and the second copper foil sheet, the second stacking unit is located between the adjacent first stacking unit and the first copper foil sheet, or the The second stacking unit is located between two adjacent first stacking units, or the second stacking unit is stacked on the first circuit substrate of the first stacking unit farthest from the first copper foil sheet. 18. The method for manufacturing a multilayer circuit board according to claim 15, wherein N=3M+1, the first copper foil sheet, the remaining M first circuit substrates, N- 2M-1 of the second circuit substrate, M+1 of the third circuit substrate and the second copper foil to form a 2N+2 layer circuit substrate, align and stack the first copper foil, The remaining M first circuit substrates, N-2M-1 second circuit substrates, M+1 third circuit substrates, and the second copper foil sheets form a laminated substrate, and the laminated The method for forming the substrate includes the steps of: Among the remaining M first circuit substrates, M second circuit substrates, and M third circuit substrates, one first circuit substrate, one second circuit substrate, and one third circuit substrate are stacked to form a circuit board with only three circuits. a third stacking unit of the substrate, thereby obtaining M third stacking units; stacking the remaining third circuit substrate and the M third stacking units between the first copper foil sheet and the second copper foil sheet, and making the remaining third circuit substrate and the first The two copper foils are directly attached to each other, and the M third stacking units are stacked between the first copper foil and the remaining third circuit substrate, so that the third circuit in each third stacking unit The substrates are all closer to the first copper foil than the first circuit substrate in the corresponding third stacking unit, so as to obtain the laminated substrate. 19. The method for manufacturing a multilayer circuit board according to claim 18, wherein, in the third stacking unit, the third circuit substrate is arranged between adjacent first circuit substrates and second circuit substrates between, or the first circuit substrate is arranged between the adjacent third circuit substrate and the second circuit substrate, or the second circuit substrate is arranged between the adjacent third circuit substrate and the first circuit substrate . 20. The method for manufacturing a multilayer circuit board according to claim 15, wherein making N-2M-1 first circuit substrates into N-2M-1 second circuit substrates comprises the steps of: On each of the first conductive circuit patterns in the N-2M-1 first circuit substrates, the first film and a release film are sequentially laminated, and on the N-2M-1 first circuit substrates A protective film is pasted on the surface of each second conductive circuit pattern in the method; Pre-pressing the first circuit substrate, the first film, the release film and the protective film, so that the first film and the first circuit substrate are bonded together, and the protective film is bonded to the first Two conductive circuit graphics: removing the release film; forming the at least one first through hole in the first film through a laser drilling process, and part of the first conductive circuit pattern is exposed from the at least one first through hole; forming a first conductive material in the at least one first through hole by printing conductive paste; and removing the protection film. 21. The method for manufacturing a multilayer circuit board according to claim 15, wherein making M+1 first circuit substrates into M+1 third circuit substrates comprises the steps of: Lay the second film and a release film sequentially on each of the first conductive circuit patterns in the M+1 first circuit substrates, and on each of the M+1 first circuit substrates A third film and another release film are pasted on the surface of the second conductive circuit pattern; Pre-pressing the first circuit substrate, the second film, the third film and two release films, so that the second film and the third film are bonded to both sides of the first circuit substrate; removing the release film; The at least one second through hole is formed in the second film through a laser drilling process, part of the first conductive circuit pattern is exposed from the at least one second through hole, and the third through hole is formed through a laser drilling process. The at least one third through hole is formed in the film, and part of the second conductive circuit pattern is exposed from the at least one third through hole; and A second conductive material is formed in the at least one second through hole by printing conductive paste, and a third conductive material is formed in the at least one third through hole by printing conductive paste. 22. A method for making a multilayer circuit board, comprising the steps of: Provide N+1 copper-clad substrates, wherein N is a natural number greater than or equal to 1, and each of the copper-clad substrates includes an insulating layer and a first copper foil layer and a second copper foil layer attached to the opposite sides of the insulating layer. Copper foil layer; making the first copper foil layer of each of the copper-clad substrates to form a first conductive circuit pattern, making the second copper foil layer of each of the copper-clad substrates to form a second conductive circuit pattern, and the The first conductive circuit pattern and the second conductive circuit pattern are electrically connected to each other through at least one conductive hole, so that the N+1 copper-clad substrates are made into N+1 first circuit substrates; Take N first circuit substrates among the N+1 first circuit substrates, and attach the first conductive circuit pattern surface on each of the N first circuit substrates to the surface of the first circuit substrate. A film, the first film has at least one first through hole, the first conductive material is filled in the at least one first through hole, and the first conductive material is electrically connected to the adjacent first conductive circuit pattern , so that the N first circuit substrates are made into N second circuit substrates; Pressing and bonding N second circuit substrates and the remaining first circuit substrate at a time to form a 2N+2 layer circuit board, in the 2N+2 layer circuit board, each of the second circuit substrates in the second circuit substrate A film is closer to the first circuit substrate than the second conductive circuit pattern, and adjacent insulating layers are bonded together through the first film. 23. The method for manufacturing a multilayer circuit board according to claim 22, wherein making N first circuit substrates into N second circuit substrates comprises the steps of: Lay the first film and a release film sequentially on the first conductive circuit pattern of each of the N first circuit substrates, and in the N first circuit substrates A protective film is pasted on the surface of the second conductive circuit pattern of each of the first circuit substrates; Pre-pressing the first circuit substrate, the first film, the release film and the protective film, so that the first film and the first circuit substrate are bonded together, and the protective film is bonded to the first 2. On the graph of the conductive circuit; removing the release film; forming the at least one first through hole in the first film through a laser drilling process, and part of the first conductive circuit pattern is exposed from the at least one first through hole; forming a first conductive material in the at least one first through hole by printing conductive paste; and removing the protection film. 24. A multilayer circuit board, characterized in that, the multilayer circuit board is made by the method for manufacturing a multilayer circuit board according to any one of claims 1 to 23, and the multilayer circuit board comprises Multi-layer insulating layers, multi-layer films and multi-layer conductive circuit patterns, one layer of said conductive circuit patterns are arranged on opposite sides of each layer of insulating layer, and the conductive circuit patterns on both sides of each layer of insulating layer are arranged on the insulating layer At least one conductive hole in the film is electrically connected, and a layer of the conductive circuit pattern is provided on the opposite sides of each layer of film, and the conductive circuit patterns on the opposite sides of each layer of film are electrically connected through the conductive material arranged in the film, The conductive material in the film is formed by printing conductive paste.