WO2007097366A1

WO2007097366A1 - Multilayer printed wiring board and method for manufacturing same

Info

Publication number: WO2007097366A1
Application number: PCT/JP2007/053201
Authority: WO
Inventors: Katsufumi Hiraishi; Kazunori Ueda; Yoshihiro Goto; Naoya Kitamura; Shohei Arai
Original assignee: Nippon Steel Chemical Co., Ltd.
Priority date: 2006-02-21
Filing date: 2007-02-21
Publication date: 2007-08-30
Also published as: KR20130004530A; KR101262135B1; KR101262136B1; KR20080094110A

Abstract

Disclosed is a method for manufacturing a multilayer printed wiring board which comprises a step for preparing a wiring board having a first insulating layer composed of a polyimide or a first liquid crystal polymer and a wiring circuit formed on at least one side of the first insulating layer, and a conductor layer substrate having a second insulating layer composed of a second liquid crystal polymer having a melting point lower than the heat distortion temperature of the polyimide and/or the melting point of the first liquid crystal polymer and a conductor layer arranged on one side of the second insulating layer, and a step for arranging the wiring board and the conductor layer substrate in such a manner that the second insulating layer side of the conductor layer substrate faces the wiring board and continuously joining them in layers under heated and pressurized conditions by using a hot pressing apparatus.

Description

Specification

Multilayer printed wiring board and manufacturing method thereof

Technical field

The present invention relates to a multilayer printed wiring board and a method for manufacturing the same.

Background art

[0002] In recent years, the performance of electronic devices has been remarkably improved. In particular, communication devices and computers are required to respond to higher frequencies in addition to higher operating speeds! In order to increase functionality and portability, there is a need for further reductions in size and thickness.

[0003] Therefore, high-speed and low-loss signal transmission, high-density wiring, thinning, light weight, etc. are required for printed wiring boards mounted on these devices. These demands on the printed wiring board are directly directed to further lowering the dielectric constant, lowering the dielectric loss tangent and thickness, and reducing the weight of the substrate material. It has been a long time since multilayer printed wiring boards using the build-up method have been adopted as a means to solve these requirements.

[0004] In addition, a material using a thermosetting resin such as an epoxy resin or a polyimide resin is widely known as an interlayer insulating material for a multilayer printed wiring board. These thermosetting resins have good heat resistance and other properties useful for high-density multilayer printed wiring boards. However, the thermosetting resin does not necessarily have a sufficiently low dielectric constant and a low dielectric loss tangent characteristic, and thus sufficiently satisfies the high frequency characteristics required for electronic equipment. It wasn't.

[0005] Therefore, a multilayer printed wiring board using a liquid crystal polymer, which is a thermoplastic resin, as an interlayer insulating material has been proposed as satisfying the high frequency characteristics. Such a liquid crystal polymer is excellent in each characteristic of a low dielectric constant and a low dielectric loss tangent, and therefore excellent in a high speed and low loss signal transmission property in a high frequency region of a multilayer printed wiring board.

[0006] As a multilayer printed wiring board using such a liquid crystal polymer as an interlayer insulating material, for example, JP-A-8-97565 (Reference 1) discloses a wiring in which a circuit layer (wiring circuit) is formed. When forming a laminate by stacking substrates, a liquid crystal polymer having a melting point at least 10 ° C lower than the melting point of the liquid crystal polymer of the wiring substrate is interposed between the wiring substrates as an adhesive layer. In the specification, it is described that the laminated body is formed by placing the laminated wiring boards together with the release pads on a lamination press and laminating them. In addition, it is described in the specification that, according to this proposal, a multilayer printed wiring board can be obtained without the need to heat the liquid crystal polymer component of the circuit layer above its melting point.

[0007] Further, Japanese Patent Laid-Open No. 2001-244630 (Document 2) discloses that a printed circuit board (wiring board) on which a wired circuit is formed is lower in heat resistance than a liquid crystal polymer film used for an insulating layer of the wired circuit board. A method of disposing the liquid crystal polymer film on the top and bottom surfaces of the liquid crystal polymer film and bonding it with a pair of heating rolls is disclosed. In addition, in the specification, a liquid crystal polymer film having low heat resistance is used as an adhesive layer, as in the case of using the above-described laminating press, and at this time, on the outer surface of the printed circuit board (wiring board). It also describes that a liquid crystal polymer film having lower heat resistance is further laminated as a protective film. Furthermore, in the specification, in order to prevent each heating roll from damaging the wiring circuit formed on the surface (outer surface) of each wiring circuit board, a release sheet is hung between the rolls. In addition, it is described that pressure is applied by a roll while bringing the release sheet into contact with the surface of each printed circuit board. Also, in this specification, according to this proposal, it is possible to obtain a multilayer printed circuit board (multilayer printed wiring board) having good appearance, sufficient dimensional stability and high adhesive strength at low cost. Are listed.

Disclosure of the invention

[0008] However, among the above-described conventional techniques, those laminated by the former (Reference 1) laminating press are inferior in productivity compared to those laminated by so-called roll laminating. Is well known. In addition, when laminating at a temperature higher than the melting point of the liquid crystal polymer at the time of laminating press, there was a problem that the circuit flowed out and deformed.

[0009] On the other hand, the latter (Reference 2) laminated with a heating roll is superior to the one laminated with a laminating press in terms of productivity as described above, but the surface of each printed circuit board ( There was a problem that it was difficult to completely avoid damage to the wiring circuit formed on the outer surface.

[0010] That is, according to the method described in Document 2, the first step of laminating with a pressure roll Furthermore, because the liquid crystal polymer layer with lower heat resistance (melting point) than the outer insulating layer is placed on the center side where the pressure roll force is further away, the heat and pressure conditions at the time of lamination become more severe, There are concerns about defects such as deformation of the wiring circuit. Similarly, if the initial lamination process is actually performed, a release sheet such as a glass woven cloth-impregnated Teflon (registered trademark) sheet is considered to be essential to prevent circuit damage. In some cases, this may hinder subtle temperature control in the lamination process and lead to defects in the multilayer circuit board.

[0011] Further, in the multilayer printed wiring boards as described in the above-mentioned documents 1 and 2, the thickness of the multilayer printed wiring board is reduced in order to realize further higher density and smaller size. In this case, the heat resistance of the insulating layer is not always sufficient!

[0012] The present invention has been made in view of the above-described problems of the prior art, and is a method for continuously producing a multilayer printed wiring board having an insulating layer having a liquid crystal polymer strength. A multilayer printed wiring board that can prevent deformation of a wiring circuit formed on the outer surface, and a multilayer printed wiring that is obtained by the manufacturing method and that can simultaneously realize heat resistance and excellent high-frequency characteristics. The purpose is to provide a board.

[0013] As a result of intensive studies to achieve the above object, the present inventors have formed a first insulating layer having polyimide or a first liquid crystal polymer force and at least one surface of the first insulating layer. And a second insulating layer comprising a second liquid crystal polymer having a melting point lower than the thermal deformation temperature of the polyimide and a melting point lower than Z or the melting point of the first liquid crystal polymer. And a step of preparing a conductor layer substrate having a conductor layer laminated on one side of the second insulating layer;

The wiring board and the conductor layer board are continuously stacked under heat and pressure by using a heat and pressure treatment facility, with the second insulating layer side of the conductor layer board facing the wiring board. Process,

It has been found that a method of manufacturing a multilayer printed wiring board including the above can prevent deformation of a wiring circuit formed on the outermost surface of the multilayer printed wiring board, and has completed the present invention.

[0014] The method for producing a multilayer printed wiring board of the present invention comprises using polyimide or the first liquid crystal polymer. A wiring board having a first insulating layer and a wiring circuit formed on at least one side of the first insulating layer, and a melting point and a Z that are lower than the thermal deformation temperature of the polyimide or the first liquid crystal Preparing a conductor layer substrate having a second insulating layer made of a second liquid crystal polymer having a melting point lower than the melting point of the polymer, and a conductor layer laminated on one side of the second insulating layer;

It is a method including.

[0015] Further, in the method for producing a multilayer printed wiring board according to the present invention, two conductor layer substrates are prepared, and when the wiring substrate and the conductor layer substrate are laminated, the wiring substrate and the two conductors are stacked. A layer substrate is placed with the wiring substrate in between, the two conductor layer substrates are arranged with the second insulating layer side facing the wiring substrate, respectively, and heated and pressurized using a heating and pressing treatment facility. It is preferable to laminate continuously.

[0016] Further, in the method for producing a multilayer printed wiring board of the present invention, the second liquid crystal polymer may have a melting point lower by 5 to 60 ° C than the melting point of the first liquid crystal polymer. preferable.

[0017] In the method for producing a multilayer printed wiring board of the present invention, it is preferable that the wiring board and the conductor layer board are each wound in a roll shape.

[0018] Further, in the method for producing a multilayer printed wiring board of the present invention, when laminating the wiring board and the conductor layer board, the wiring board and the conductor layer board are respectively drawn out, and a roll 'toe' roll It is preferable to laminate in a continuous manner.

[0019] Further, in the method for producing a multilayer printed wiring board of the present invention, it is preferable that the heating and pressurizing treatment equipment is a roll laminator.

[0020] Further, in the method for producing a multilayer printed wiring board of the present invention, it is preferable that a roll linear pressure of the roll laminator is 10 to 250 kN / m! /.

[0021] The method for producing a multilayer printed wiring board of the present invention preferably further includes a step of surface-treating the surface of the second insulating layer of the conductor layer substrate. Furthermore, in the method for producing a multilayer printed wiring board according to the present invention, when the wiring board and the conductor layer board are laminated, the wiring board and the conductor layer board are laminated under heat and pressure (temporary lamination). Then, after obtaining a laminated body (temporary laminated body), it is preferable to perform a high temperature heat treatment by heating the laminated body using a heat treatment equipment.

[0023] Further, in the method for producing a multilayer printed wiring board of the present invention, when performing the high temperature heat treatment, the laminate is subjected to a high temperature heat treatment temperature T that satisfies the condition represented by the following formula (F1).

(The melting point of the second liquid crystal polymer) 15 ° C≤T≤ (The melting point of the second liquid crystal polymer) + 20 ° C '· • (F1)

It is preferable to heat with.

Furthermore, in the method for producing a multilayer printed wiring board of the present invention, it is preferable that the high temperature heat treatment time is in the range of 10 to 180 seconds when performing the high temperature heat treatment.

[0025] Further, in the method for producing a multilayer printed wiring board of the present invention, in obtaining the multilayer body, the multilayer heat treatment satisfying the condition represented by the following formula (F2) for the wiring substrate and the conductor layer substrate: Temperature T:

2

(The melting point of the second liquid crystal polymer) 100 ° C≤T≤ (The melting point of the second liquid crystal polymer) 20 ° C '

2

•. (F2)

In addition, it is preferable to laminate (temporary lamination).

[0026] The multilayer printed wiring board of the present invention is a multilayer printed wiring board in which wiring circuit layers and insulating layers are alternately laminated.

One of the two insulating layers adjacent to each other via the wiring circuit layer is a polyimide resin layer, and the other insulating layer is a liquid crystal polymer layer.

[0027] Further, in the multilayer printed wiring board of the present invention, in the laminated structural unit, the liquid crystal polymer layer is disposed on the opposite side of the liquid crystal polymer layer from the side adjacent to the polyimide resin layer via the wiring circuit layer. U is preferred to be further provided.

[0028] Further, in the multilayer printed wiring board of the present invention, in the laminated structural unit, the roughness of the boundary surface between the polyimide resin layer and the liquid crystal polymer layer is in the range of 4 to 6 μm. It is preferable.

[0029] In the multilayer printed wiring board of the present invention, the roughness of the boundary surface between the polyimide resin layer and the liquid crystal polymer layer in the laminated structural unit may be less than 4 m.

[0030] According to the present invention, in a method for continuously producing a multilayer printed wiring board having an insulating layer that also has liquid crystal polymer power, deformation of the wiring circuit formed on the outermost surface of the multilayer printed wiring board is prevented. It is possible to provide a method for producing a multilayer printed wiring board that can be produced, and a multilayer printed wiring board obtained by the production method.

Brief Description of Drawings

FIG. 1 is a partially enlarged schematic side sectional view showing a copper clad laminate (a) and a wiring board (b) wound in a roll shape used in the first step.

[FIG. 2] FIG. 2 is a partially enlarged schematic side sectional view showing a two-layer conductor layer substrate wound in a roll shape used in the first step.

FIG. 3 is a schematic cross-sectional side view showing a peripheral portion of a heat and pressure treatment facility in a second step.

FIG. 4 is a schematic cross-sectional side view showing the periphery of the heat treatment equipment in the second step.

FIG. 5 is a schematic side cross-sectional view showing a preferred embodiment of a post-process applied to an unprocessed multilayer printed wiring board obtained by the second process (FIG. 5 (a) is a through-hole formation). Fig. 5 (b) corresponds to the plating process, and Fig. 5 (c) corresponds to the circuit formation process and the solder resist formation process.

FIG. 6 is a schematic sectional side view showing a preferred embodiment of the multilayer printed wiring board of the present invention.

FIG. 7 is a schematic side cross-sectional view showing another preferred embodiment of the multilayer printed wiring board of the present invention.

FIG. 8 is a schematic side sectional view showing a multilayer printed wiring board obtained in Example 7.

FIG. 9 is a schematic side sectional view showing a multilayer printed wiring board obtained in Example 8.

FIG. 10 is a schematic side sectional view showing a multilayer printed wiring board obtained in Example 9.

FIG. 11 is a schematic sectional side view showing a multilayer printed wiring board obtained in Example 10. FIG. 12 is a process diagram for explaining a production process for the multilayer printed wiring board obtained in Example 11.

FIG. 13 is a process diagram for explaining a production process for the multilayer printed wiring board obtained in Example 12.

FIG. 14 is a process diagram for explaining a production process for the multilayer printed wiring board obtained in Example 13.

FIG. 15 is a process diagram for explaining a process for producing a multilayer printed wiring board obtained in Example 14.

FIG. 16 is a process diagram for explaining a production process for the multilayer printed wiring board obtained in Example 15.

FIG. 17 is a process diagram for explaining a production process for the multilayer printed wiring board obtained in Example 16.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

[0033] (Method for producing multilayer printed wiring board)

First, the manufacturing method of the multilayer printed wiring board of this invention is demonstrated. The method for producing a multilayer printed wiring board according to the present invention includes a wiring board having a first insulating layer made of polyimide or a first liquid crystal polymer force, and a wiring circuit formed on at least one side of the first insulating layer, and A second insulating layer having a melting point lower than the heat distortion temperature of the polyimide and a melting point lower than the melting point of Z or the first liquid crystal polymer; and a second insulating layer formed on one side of the second insulating layer. Preparing a conductor layer substrate having a laminated conductor layer (first step);

The wiring board and the conductor layer board are continuously stacked under heat and pressure by using a heat and pressure treatment facility, with the second insulating layer side of the conductor layer board facing the wiring board. Process (second process), and

It is a method including.

[0034] First, polyimide used in the method for producing a multilayer printed wiring board of the present invention, and first and The second liquid crystal polymer will be described. The polyimide used in the method for producing a multilayer printed wiring board of the present invention is mainly composed of a polyimide having a imide bond in the molecule, and polyamide, and it is not always necessary to use only a single polyimide. It may be a mixture with fat. Polyimide can be obtained by appropriately selecting a known diamino compound and tetracarboxylic acid or an anhydrous product thereof and combining them so as to obtain desired characteristics. Furthermore, these polyimides are, for example, from 0 to 35 X 10 ^_6 Z ° C (more preferably 1 X 10 ^{_6 to} 25 X 10 ^_6 Z ° C) from the viewpoint of dimensional accuracy of the obtained multilayer printed wiring board. It is preferable to have a linear expansion coefficient in the range. In the present invention, for example, such a polyimide resin is used as a first insulating layer, and a wiring board having a wiring circuit formed on at least one surface thereof is used. In that case, a commercially available polyimide film or It is convenient to use a copper-clad laminate with polyimide and copper foil strength. When a polyimide film is used, a circuit can be formed by a known method such as sputtering to form a wiring board. When using a copper-clad laminate, any wiring circuit can be formed by a known method to form a wiring board. As such a polyimide film, Avical AH, NPI (manufactured by Kane Riki Co., Ltd.), Upilex S (manufactured by Ube Industries, Ltd.), Kapton (manufactured by Toray DuPont Co., Ltd.), etc. may be used. it can. As such a copper-clad laminate, Espanex S series and M series (both manufactured by Nippon Steel Engineering Co., Ltd.) can be used. Further, the heat distortion temperature of such a polyimide is preferably in the range of 300 to 380 ° C, and is preferably in the range of 320 to 360 ° C.

The first and second liquid crystal polymers used in the method for producing a multilayer printed wiring board of the present invention are those that form an optically anisotropic molten phase. The type of these liquid crystal polymers is not particularly limited, but so-called wholly aromatic liquid crystal polymers, that is, liquid crystal polymers that do not contain an aliphatic long chain and are substantially composed of only aromatics are preferable. Further, among these, it is more preferable to use a polyester comprising 6-hydroxy-2-naphthoic acid and p-hydroxybenzoic acid. Further, as these liquid crystal polymers, a mixture in which an appropriate kind of liquid crystal material is combined can be used. For example, various liquid crystal polymers such as a liquid crystal polymer used as an insulating layer in a commercially available copper-clad laminate. The intermediate force can also be selected and used as appropriate. In addition, these liquid crystal polymers are obtained From the viewpoint of the dimensional accuracy of the multilayer printed wiring board, for example, it is preferable that it has a linear expansion coefficient in the range of 1 X 10 — ^{6 to} 25 X 10 — ⁶ Z ° C. In the present invention, for example, such a liquid crystal polymer is used as a second insulating layer, and a wiring board having a wiring circuit formed on at least one surface thereof is used. In that case, a commercially available liquid crystal polymer film is used. Alternatively, it is convenient to use a copper clad laminate having a liquid crystal polymer and a copper foil force. As such a liquid crystal polymer film, Betastar (manufactured by KURARENE CORPORATION) or the like can be used. As such a copper-clad laminate, Espanex L series (manufactured by Nippon Steel Chemical Co., Ltd.) can be used. Further, the melting point of the first liquid crystal polymer is preferably in the range of 280 to 350 ° C. Also, the melting point of the second liquid crystal polymer is in the range of 80 to 280 ° C. It is preferable that it exists in.

[0036] Such a polyimide or the first liquid crystal polymer is a material for the first insulating layer that is useful in the present invention. The second liquid crystal polymer is a material for the second insulating layer according to the present invention. In the present invention, the second liquid crystal polymer needs to have a melting point lower than the heat distortion temperature of the polyimide and a melting point lower than Z or the melting point of the first liquid crystal polymer. is there. In this way, in the second step described later, the second liquid crystal polymer has a melting point lower than the thermal deformation temperature of the polyimide and Z or the melting point of the first liquid crystal polymer. It is possible to prevent deformation of the obtained multilayer printed wiring board while maintaining the filling property of the second liquid crystal polymer between the wiring circuits formed on at least one side of the insulating layer.

[0037] In the present invention, it is preferable that the melting point of the second liquid crystal polymer is 5 ° C or more lower than the thermal deformation temperature of the polyimide. It is more preferable that the temperature is lower. The melting point of the second liquid crystal polymer is preferably 5 to 60 ° C lower than the melting point of the first liquid crystal polymer, more preferably 10 to 60 ° C lower, more preferably 15 to 40 °. A low C is particularly preferred. If the melting point of the second liquid crystal polymer is less than the lower limit, the dimensional accuracy of the resulting multilayer printed wiring board tends to be insufficient. On the other hand, if the upper limit is exceeded, warping of the multilayer printed wiring board to be obtained can be reduced. Circuit deformation tends to increase. The heat distortion temperature in the present invention refers to a temperature at which a film starts to grow suddenly by a load when a certain load is applied to the film and the temperature is raised. And heat change The molding temperature can be measured according to the method described in ASTM D648 or ί and IS K7191, and for example, it can be measured by the following method. In other words, using a thermomechanical analyzer (TMA), a 5 g load was applied to the sample, the dimensional change of the sample was measured when the temperature was raised to 400 ° C at a temperature increase rate of 10 ° CZmin, and the elongation below Tg was measured. The heat distortion temperature can also be obtained from the intersection force between the extrapolated line and the extrapolated line extending beyond Tg. The melting point is the temperature of the endothermic peak observed when the temperature is raised to 360 ° C at a rate of 10 ° CZmin using a differential scanning calorimeter (DSC).

[0038] The forces described above for the polyimide and the first and second liquid crystal polymers used in the method for producing the multilayer printed wiring board of the present invention are described below. The multilayer printed wiring board of the present invention with reference to Figs. The manufacturing method will be described. 1 to 5 are schematic side sectional views for explaining a preferred embodiment of a method for producing a multilayer printed wiring board according to the present invention. 1 and 2 correspond to the first step, FIGS. 3 and 4 correspond to the second step, and FIG. 5 corresponds to a later step to be described later.

In the first step, first, as shown in FIG. 1B, at least one surface of the first insulating layer 12 made of the polyimide or the first liquid crystal polymer and the first insulating layer 12 is firstly shown. A wiring board 18 having a wiring circuit 16 formed on is prepared. Such a wiring board 18 is not particularly limited, but is preferably one wound in a roll shape as shown in FIG. 1 (b). By using the roll wound in this way, the multilayer printed wiring board can be manufactured by a roll 'toe' roll method, and the productivity can be further improved. In addition, such a wiring board 18 is laminated on at least one surface of the first insulating layer 12 and the first insulating layer 12 wound in a roll shape as shown in FIG. 1A, for example. The copper clad laminate 14 having the copper foil 10 can be produced by subjecting it to a circuit forming process. As such a circuit forming process, for example, a method of sequentially performing etching resist laminating, exposure, development, etching, and resist stripping on the copper-clad laminate 14 can be employed. Further, such a circuit formation process is preferably performed by a roll 'toe' roll method.

[0040] The first insulating layer 12 is not particularly limited as long as it is a layer made of the polyimide or the first liquid crystal polymer. Such a first insulating layer 12 includes the poly An imide film or a commercially available liquid crystal polymer film may be appropriately selected and used. As such a liquid crystal polymer film, Betastar (manufactured by Kurarene Co., Ltd.) or the like can be used. In addition, as the copper clad laminate 14 having the first insulating layer 12 as described above, the S-vanex L series (manufactured by Nippon Steel Corp.) and the S-vanex M series (Nippon Steel Corp. ( Etc.) can be used.

[0041] The thickness of the first insulating layer 12 can be, for example, in the range of 5 to: LOO / zm, and preferably in the range of 10 to 50 m. Furthermore, the thickness of the wiring circuit 16 can be in the range of 3 to 35 m, for example, and is preferably in the range of 5 to 25 m.

In the first step, next, as shown in FIG. 2, a second melting point having a melting point lower than the thermal deformation temperature of the polyimide and a melting point lower than the melting point of Z or the first liquid crystal polymer. A conductor layer substrate 24 having a second insulating layer 22 made of a liquid crystal polymer and a conductor layer 20 laminated on one side of the second insulating layer 22 is prepared. The second insulating layer 22 is not particularly limited as long as it is a layer having the second liquid crystal polymer force. As such second insulating layer 22, a commercially available liquid crystal polymer film may be appropriately selected and used. As such a liquid crystal polymer film, Betastar (manufactured by KURARENE CORPORATION) or the like can be used. Further, as the material of the conductor layer 20, an appropriate highly conductive metal can be used, but it is particularly preferable to use copper. In addition, as the conductor layer substrate 24 having the second insulating layer 22 as described above, Esbanex L series (manufactured by Nippon Steel Chemical Co., Ltd.) or the like can be used.

[0043] The thickness of the second insulating layer 22 can be, for example, in the range of 5 to: LOO / zm, and preferably in the range of 10 to 50 m. Furthermore, the thickness of the conductor layer 20 can be, for example, in the range of 3 to 35 / ζ πι, and preferably in the range of 5 to 25 μm.

[0044] When the wiring board 18 has the wiring circuit 16 only on one side, it is sufficient to prepare at least one such conductive layer board 24, but the wiring board 18 is on both sides. When the wiring circuit 16 is provided, it is preferable to prepare two sheets.

[0045] Further, in such a conductor layer substrate 24, the surface of the second liquid crystal polymer (the second insulating layer) may be subjected to a surface treatment before performing a second step described later. The desired strength can improve the adhesion strength of the laminated surface. Also, such a surface treatment method For example, an etching process using an alkali mixed solution or an etching process using plasma is preferably applicable.

In the second step, first, the wiring board 18 and the conductor layer board 24 are arranged with the second insulating layer side of the conductor layer board 24 facing the wiring board 18. Here, when the wiring board 18 has the wiring circuit 16 on both sides, it is shown in FIG. 3 from the viewpoint of preventing the deformation of the wiring circuit formed on the outermost surface of the obtained multilayer printed wiring board. As shown, the wiring board 18 and the two conductor layer boards 24 can be arranged with the wiring board 18 in between and the two conductor layer boards 24 arranged with the second insulating layer side facing the wiring board 18 respectively. preferable. Further, when the wiring board 18 and the conductor layer board 24 are wound in a roll shape, they can be drawn out and used.

[0047] In the second step, thereafter, the wiring board 18 and the conductor layer board 24 are continuously laminated under heat and pressure using the heating and pressure treatment equipment 27, and the outermost surface is not processed. A multilayer printed wiring board (outer layer unprocessed multilayer printed wiring board) is obtained (Fig. 3). Such a heating and pressurizing treatment equipment 27 is preferably one that can be continuously treated by a roll 'toe' roll method from the viewpoint of productivity. In addition, as such a heat and pressure treatment equipment 27, an apparatus such as a roll laminator, a double steel belt press, or a continuous press apparatus (for example, MVLP series manufactured by Meiki Seisakusho Co., Ltd.) can be used from the viewpoint of productivity. It is preferable to use a roll laminator. When a roll laminator is used as the heat and pressure treatment equipment 27, the roll line pressure (laminate pressure) by the roll laminator is preferably 10 to 25 OkNZm, more preferably 25 to 150 kNZm. When the roll line pressure is less than the lower limit, the filling property of the second liquid crystal polymer between the wiring circuits formed on at least one side of the first insulating layer, and the wiring circuit and the second insulating layer On the other hand, if the upper limit is exceeded, the warp of the resulting multilayer printed wiring board tends to increase, or the thickness change of the second liquid crystal polymer tends to increase. The roll temperature (surface temperature) of the roll laminator is preferably 150 to 300 ° C.

[0048] In addition, in the second step, when the wiring board 18 and the conductor layer board 24 are stacked, the wiring board 18 and the conductor layer board 24 are stacked under heat and pressure. After the layer (temporary laminate) is obtained to obtain the laminate 26 (temporary laminate 26), the laminate 26 is heated using a heat treatment equipment 29 as shown in FIG. It is preferable to obtain a non-caloric multilayer printed wiring board (outer layer unprocessed multilayer printed wiring board 28).

[0049] In this way, after obtaining the temporary laminate, high-temperature heat treatment is performed to obtain an unprocessed multilayer printed wiring board using only the heating and pressure treatment equipment such as a roll laminator. Compared to the method of laminating a conductor layer substrate to obtain an unprocessed multilayer printed wiring board, it is advantageous in the points described below. That is, when only the heating and pressurizing processing equipment such as a roll laminator is used to obtain the multilayered printed wiring board without processing the outer layer by laminating the wiring board and the conductor layer board, the wiring can be performed by a short heating and pressing process. The filling of the second liquid crystal polymer between the circuits, the adhesion between the wiring circuit and the second insulating layer, and the prevention of deformation of the resulting multilayer printed wiring board should be satisfied. These layers need to be laminated. For example, if the influence of variations in raw material quality such as heat resistance and thickness is taken into account, there is a risk that delicate condition management in the lamination process may be required. In addition, even when good lamination is performed under such condition control, the multilayer printed wiring board can be used in subsequent processes due to residual stress that is considered to be caused by lamination under heating and pressing conditions. There is a risk of warping, which may cause problems when mounting and using parts as a multilayer printed wiring board.

[0050] On the other hand, when a high temperature heat treatment is performed after obtaining a temporary laminate as described above to obtain an outer layer unprocessed multilayer printed wiring board, residual stress is applied to the obtained outer layer unprocessed multilayer printed wiring board. Is unlikely to occur. Therefore, warpage of the multilayer printed wiring board can be sufficiently suppressed in this way. In such a case, the above three viewpoints should be satisfied at the same time when producing a multilayer printed wiring board as compared with the case of laminating using only the heat and pressure treatment equipment 27 such as a roll laminator. Manufacturing conditions can be easily found.

[0051] When the temporary laminated body 26 is obtained and then subjected to high-temperature heat treatment to obtain the outer layer unprocessed multilayer printed wiring board 28, the wiring board 18 and the conductor are obtained in obtaining the temporary laminated body 26. Lamination heat treatment temperature for layer substrate 24 that satisfies the condition expressed by the following formula (F2) (temporary lamination heat treatment temperature) T:

2

(The melting point of the second liquid crystal polymer) 100 ° C≤T≤ (The melting point of the second liquid crystal polymer) 20 ° C ' •. (F2)

Is preferably laminated (temporary lamination). Temporary lamination heat treatment temperature T is less than the lower limit

2

Then, the filling property of the second liquid crystal polymer between the wiring circuits formed on at least one surface of the first insulating layer and the adhesion between the wiring circuit and the second insulating layer are insufficient. On the other hand, if the upper limit is exceeded, warping of the resulting multilayer printed wiring board cannot be sufficiently suppressed.

[0052] In addition, when the high temperature heat treatment is performed after obtaining the temporary laminate 26 in this way to obtain the outer layer unprocessed multilayer printed wiring board 28, the temporary laminate 26 is divided into the following number in performing the high temperature heat treatment. High-temperature heat treatment temperature T that satisfies the condition expressed by formula (F1):

It is preferable to heat with. When the high-temperature heat treatment temperature T is less than the lower limit, the filling property of the second liquid crystal polymer between the wiring circuits formed on at least one surface of the first insulating layer, and the wiring circuit and the second insulating layer On the other hand, if the upper limit is exceeded, the wiring circuit formed on at least one surface of the first insulating layer tends to be deformed or wrinkled.

[0053] Further, in performing the high temperature heat treatment, the high temperature heat treatment time is preferably 5 seconds or more, more preferably in the range of 10 to 180 seconds. When the high-temperature heat treatment time is less than 5 seconds, the filling property of the second liquid crystal polymer between the wiring circuits formed on at least one side of the first insulating layer, and the wiring circuit and the second insulating layer Adhesiveness tends to be inadequate. On the other hand, if it exceeds 180 seconds, the wiring circuit formed on at least one surface of the first insulating layer may be deformed or damaged.

[0054] In addition, such a heat treatment equipment 29 is preferably capable of being continuously treated by a roll 'toe' roll method from the viewpoint of productivity. Examples of such heat treatment equipment 29 include a tunnel furnace, a far-infrared furnace, and a hot air drying furnace.

[0055] In the method for producing a multilayer printed wiring board of the present invention, the outer layer unprocessed multilayer printed wiring board obtained by the second step is subjected to a post-process described below as necessary. A wiring board can be obtained. Further, the multilayer printed wiring board of the present invention is manufactured. After the outer layer unprocessed multilayer printed wiring board is cut into the product dimensions of the multilayer printed wiring board, a post-process may be performed for each of the cut pieces. The post-process may be performed by continuously processing the printed wiring board as it is by a roll-to-roll method.

[0056] Further, in the method for producing a multilayer printed wiring board of the present invention, if necessary, the outer layer uncovered multilayer printed wiring board may be wound and temporarily stored in a roll shape. In such a case, if a wiring circuit is formed on the surface as in the conventional method, there is a risk of damaging the wiring circuit layer. According to the present invention, the outermost surface is a conductor layer. Absent.

[0057] Further, as subsequent processes, for example, a through-hole forming process as shown in Fig. 5 (a), a plating process as shown in Fig. 5 (b), and a process as shown in Fig. 5 (c) Circuit formation processing and soldering One resist formation processing can be mentioned. In addition, as these subsequent steps, known methods can be appropriately employed.

In the method for producing a multilayer printed wiring board of the present invention as described above, the outermost unprocessed multilayer printed wiring board obtained by the second step is a conductor layer that is not yet a wiring circuit. Therefore, there is no room for the problem of deformation of the wiring circuit in the second step.Furthermore, after forming the wiring circuit by patterning the conductor layer after the second step, the multi-layer printed wiring board is formed. There is little risk of deformation of the wiring circuit formed on the outer surface.

[0059] Further, according to the method for producing a multilayer printed wiring board of the present invention, the second step can be continuously performed by a roll 'toe' roll method, and in that case, the multilayer printed wiring board is expensive. It becomes possible to manufacture with productivity.

The preferred embodiment of the method for producing a multilayer printed wiring board of the present invention has been described above, but the method for producing a multilayer printed wiring board of the present invention is not limited to the above embodiment. For example, in the method for producing a multilayer printed wiring board according to the present invention, the wiring board may have a plurality of the first insulating layers. That is, it is possible to manufacture a multilayer printed wiring board having four or more layers by using a multi-layered wiring board as the wiring board, and further, according to the method for manufacturing a multilayer printed wiring board of the present invention. The resulting multilayer printed wiring board can be further multilayered. Also, the multilayer printed wiring of the present invention In the manufacturing method of the plate, it is possible to use an appropriate highly conductive metal in addition to copper as a material for the wiring circuit.

[0061] (Multilayer printed wiring board)

Next, the multilayer printed wiring board of the present invention will be described. The multilayer printed wiring board of the present invention has a structure in which a plurality of wiring circuit layers (wiring circuit, conductor layer) and a plurality of insulating layers are alternately laminated. In the multilayer printed wiring board of the present invention, one of the two insulating layers adjacent to each other via the wiring circuit layer is a polyimide resin layer, and the other insulating layer is a liquid crystal polymer. It is necessary to include laminated structural units that are layers. In the present invention, a laminated structure in which one of the two insulating layers adjacent to each other through the wiring circuit layer is a polyimide resin layer and the other insulating layer is a liquid crystal polymer layer. By including the unit, it is possible to achieve both heat resistance and excellent high-frequency characteristics.

[0062] The multilayer printed wiring board of the present invention can be manufactured, for example, by the above-described method for manufacturing a multilayer printed wiring board of the present invention. That is, a wiring board having a first insulating layer made of polyimide or a first liquid crystal polymer and a wiring circuit formed on at least one surface of the first insulating layer, and a temperature lower than the thermal deformation temperature of the polyimide A second insulating layer having a second liquid crystal polymer force having a melting point and a melting point lower than the melting point of Z or the first liquid crystal polymer, and a conductor layer laminated on one side of the second insulating layer. A step of preparing a conductor layer substrate;

When at least one wiring board has a first insulating layer (polyimide resin layer) made of polyimide, the multilayer printed wiring board of the present invention can be manufactured. Monkey.

[0063] The multilayer printed wiring board of the present invention is, for example, as shown in FIG. 6, in a multilayer printed wiring board 50 having the above-described laminated structure, two insulating layers 5 adjacent to each other with a wiring circuit layer 52 interposed therebetween. One of the insulating layers 4a and 54b is a polyimide resin layer, and the other insulating layer is a liquid crystal polymer layer. It includes a laminated structural unit 56 that is a remer layer. Such a laminated structural unit 56 may extend over the entire laminated structure of the multilayer printed wiring board 50, or may be provided at one or more appropriate portions in the entire laminated structure. Good.

[0064] It is preferable to use polyimide resin as the material of one insulating layer 54a, but is not limited to this, heat resistance of the insulating layer is ensured, and an appropriate low dielectric constant and low dielectric loss tangent are provided. As long as it has each of these characteristics, you may use another thermosetting resin. Examples of such polyimide resin include those similar to the polyimide used in the above-described method for producing a multilayer printed wiring board of the present invention.

[0065] Further, as the material of the other one insulating layer 54b, it is preferable to use a liquid crystal polymer, but not limited to this, as long as it has excellent characteristics of low dielectric constant and low dielectric loss tangent, Other thermoplastic rosins may be used. Examples of such a liquid crystal polymer include the same liquid crystal polymers as those used in the above-described method for producing a multilayer printed wiring board of the present invention.

[0066] Further, as a material of the wiring circuit layer (wiring circuit) 52, a force capable of using an appropriate highly conductive metal, in particular, a copper foil is preferably used.

[0067] When the insulating layer 54a is a polyimide resin layer and the insulating layer 54b is a liquid crystal polymer layer, the thickness of the insulating layer 54a can be, for example, about 5 to: LOO m, and the thickness of the insulating layer 54b. Can be, for example, about 10 to about LOO m. Further, the thickness of the wiring circuit layer 12 can be set to about 3 to 35 μm, for example.

[0068] Such a multilayer printed wiring board of the present invention has an excellent balance of properties due to the combination of the good heat resistance of polyimide resin and the excellent high-frequency properties of the liquid crystal polymer. In addition, since the insulating layer according to the present invention does not include a reinforcing material such as a glass woven fabric and a ramid nonwoven fabric, the resulting multilayer printed wiring board is excellent in densification, thinning, and weight reduction, and powder falling off. The resulting yield loss is reduced.

[0069] Further, the multilayer printed wiring board of the present invention, for example, as shown in FIG. 7, is adjacent to the polyimide resin layer (insulating layer 54a) of the liquid crystal polymer layer (insulating layer 54b) in the laminated structural unit 56a. A liquid crystal polymer layer (insulating layer 54c) may be further provided on the side opposite to the mating side via the wiring circuit layer 52a. [0070] In the case of such a structure in which the liquid crystal polymers are laminated adjacent to each other, there is a concern about the positional displacement of the wiring circuit due to heating and pressurization in the manufacturing process of the multilayer printed wiring board. The melting point of the liquid crystal polymer layer 54b is preferably 5 to 60 ° C higher than the melting point of the liquid crystal polymer layer 54c, more preferably 10 to 60 ° C, and particularly preferably 15 to 40 ° C higher. The melting point of the liquid crystal polymer according to the present invention refers to the temperature of the endothermic peak observed when the temperature is increased to 360 ° C. at a temperature increase rate of 10 ° C. Zmin using a differential scanning calorimeter (DSC).

[0071] Thus, the multilayer printed wiring board including the multilayer structural unit 56a is advantageous in that it can easily realize higher-order multilayering of the printed wiring board having the multilayer structural unit 56 as a skeleton structure. is there.

[0072] Further, in the multilayer printed wiring board of the present invention, in the laminated structural units 56 and 56a, the boundary surface between the polyimide resin layer (insulating layer 54a) and the liquid crystal polymer layer (insulating layer 54b) (see FIG. 6, indicated by arrow A. The roughness (Rz) of) is preferably in the range of 4 to 6 μm. When the roughness of the interface is within the above range, the gap between the layers that does not adversely affect the high-speed and low-loss signal transmission in the high-frequency region that can occur when the roughness of the interface is significantly large. It is possible to secure sufficient interlayer adhesion strength.

[0073] Further, the roughness (Rz) of the boundary surface may be less than 4 μm, preferably in the range of 1 to 3 μm. In this case, a high-speed, low-loss signal in the high-frequency region may be used. The adverse effect on transmission performance can be avoided more reliably.

[0074] The roughness of the boundary surface is controlled by, for example, preliminarily forming the polyimide resin layer when the wiring layer 52 is formed by etching and patterning a conductor layer previously laminated on the polyimide resin layer (insulating layer 54a). The surface roughness of the conductor layer such as copper foil laminated on the layer (insulating layer 54a), in other words, the surface roughness of the surface (laminated surface) on which the liquid crystal polymer layer (insulating layer 54b) is laminated, etc. It can be performed by an appropriate method.

In the multilayer printed wiring board of the present invention, the boundary surface A between the polyimide resin layer (insulating layer 54a) and the liquid crystal polymer layer (insulating layer 54b) is formed in the laminated structural units 56 and 56a. The laminated surface of the liquid crystal polymer layer 54b facing the polyimide resin layer 54a and the laminated surface of the liquid crystal polymer layer 54c facing the liquid crystal polymer layer 54b are respectively surface-treated in advance. It is preferable. In this way, it is possible to obtain a good interlayer adhesion strength by closely contacting the layers with no gap.

[0076] In particular, when the surface roughness is less than 4 μm as described above, performing surface treatment reduces the adverse effects on high-speed and low-loss signal transmission and increases the interlayer adhesion strength in the high-frequency region. This is more preferable because it is possible to achieve a good balance.

[0077] Such a surface treatment cage is applied before the lamination integration step. Further, as such a surface treatment cache method, etching treatment with an alkali mixed solution or etching treatment with plasma is desirable.

[0078] In the vacuum hot press process, for example, the maximum temperature is controlled in the range of 220 to 300 ° C, the press pressure is controlled in the range of 4 to 8MPa, and in the lamination process, for example, the maximum temperature By controlling the laminating pressure (linear pressure) in the range of 200 to 300 ° C and in the range of 2 to 200kNZ m, the thermoplastic resin can be softened or fluidized appropriately, providing sufficient interlayer adhesion Ensuring strength can be realized.

Hereinafter, a method for producing the multilayer printed wiring board of the present invention will be described.

FIG. 12 is a process diagram showing a method for producing a four-layer printed wiring board (corresponding to Example 11 to be described later) centering on a polyimide resin layer.

First, a double-sided copper-clad laminate 502 in which a polyimide resin layer is used as an insulating layer and copper foils 503 are laminated on both sides is prepared (see FIG. 12 (a)). As the double-sided copper-clad laminate 502, a commercially available double-sided copper-clad laminate can be used. Then, a wiring circuit layer 504 is formed on the double-sided copper-clad laminate 502 by an arbitrary method (see FIG. 12 (b)). Here, for example, the wiring circuit layer 504 may be formed on a polyimide film by sputter plating. The thicknesses of the polyimide resin layer and the wiring circuit layer (copper foil) are preferably as described above.

Next, a single-sided copper-clad laminate 506 having a liquid crystal polymer as an insulating layer is thermocompression bonded to both sides of the double-sided wiring board 505 having the circuit formed as described above (see FIG. 12 (c)). Reference numeral 507 denotes a hot press hot platen. Here, it is preferable to use a liquid crystal polymer having the same melting point that is heat-pressed on both sides of the double-sided wiring board 505 in order to satisfactorily fill the liquid crystal polymer between the circuits. The preferred melting point of the liquid crystal polymer is in the range of 250 to 350 ° C, and the heating temperature during heating and pressurization is 0 to 50 ° C lower than the melting point of the liquid crystal polymer. It is preferable. The pressurization is preferably performed at 4 to 8 MPa for 5 to 60 minutes. Here, heating temperature force during heating / pressurization of the liquid crystal polymer When the temperature is lower than the melting point of the liquid crystal polymer by 50 ° C or more, the wiring circuit of the wiring board may be deformed, and the pressurization range is less than 4 MPa. There is a possibility that the liquid crystal polymer is insufficiently filled between the wiring circuits. On the other hand, the heating temperature of the liquid crystal polymer (heating temperature during pressurization) is higher than the melting point of the liquid crystal polymer, or if the pressure range exceeds 8 MPa, the liquid crystal polymer may seep out of the substrate (wiring board). Voids may be generated in the liquid crystal polymer layer.

Next, after heating and pressurizing, the substrate is cooled to obtain a laminate 508 (see FIGS. 12D and 12E). These manufacturing conditions are the same in the similar manufacturing method described below. In addition, the obtained laminate 508 forms a through hole 509 by a known method such as an NC drill (see FIG. 12 (f)), and is subjected to desmear treatment to form a panel metal 510 (FIG. 12 ( g)). Then, the outermost layer 511 is etched and patterned by a tenting method to form a wiring circuit layer 512 and a solder resist layer 513 to obtain a multilayer printed wiring board 501 (see FIG. 12 (h)). ).

FIG. 13 is a process diagram showing a method for producing a four-layer printed wiring board (corresponding to Example 12 to be described later) centered on a polyimide resin layer by a roll-to-roll method.

[0085] First, a double-sided copper clad laminate 602 wound in a roll shape in which a polyimide resin layer is used as an insulating layer and copper foil 603 is laminated on both sides thereof is prepared, and a wiring circuit layer 604 is formed by an arbitrary method. A double-sided wiring board 605 formed and wound into a roll is obtained (see FIG. 13 (a)). As the double-sided copper clad laminate 6 02, a commercially available double-sided copper clad laminate can be used. The thicknesses of the polyimide resin layer and the wiring circuit layer (copper foil) are preferably as described above.

Next, a two-sided single-sided copper-clad laminate 606 wound in a roll shape using a liquid crystal polymer as an insulating layer was prepared. Then, two single-sided copper-clad laminates 606 are thermocompression bonded to both sides of the double-sided wiring board 605 formed with the circuit as described above to obtain a laminate 608 (see FIGS. 13 (b) and 13 (c)). ). Reference numeral 607 indicates a roll. Here, it is preferable to use a liquid crystal polymer having the same melting point as the liquid crystal polymer to be heat-pressed on both sides of the double-sided wiring board 605 in order to satisfactorily fill between the circuits on both sides. The range of the melting point of the liquid crystal polymer used is the same as in the press process, but the heating temperature at the time of heating and pressurizing is 0 than the melting point of the liquid crystal polymer. It is preferable that the temperature be lower by -80 ° C. In addition, it is preferable to pass the roll at a laminating pressure (linear pressure) of 2 to 200k NZm! /.

[0087] These manufacturing conditions are the same in the similar manufacturing method described below. Here, heating temperature force during heating / pressurization of liquid crystal polymer If the temperature is lower than the melting point of liquid crystal polymer by 80 ° C or more, the wiring circuit of the wiring board may be deformed, and the pressure range is less than 2 kN Zm. Insufficient filling of the liquid crystal polymer between the wiring circuits. On the other hand, if the heating temperature is applied to the liquid crystal polymer and the heating temperature during pressurization is higher than the melting point of the liquid crystal polymer or the pressure range exceeds 200 kNZm, the liquid crystal polymer may seep out to the outside of the substrate, or within the liquid crystal polymer layer. There is a risk of voids.

[0088] Next, the obtained laminate 608 is cut, and after that, through holes 609 are formed by the same method as described above (see FIG. 13 (d)), desmear treatment is performed, and the panel members are formed. Form 610 (see Fig. 13 (e)). Then, the outermost layer 611 is etched and patterned by a tenting method to form a wiring circuit layer 612 and further a solder resist layer 613 to obtain a multilayer printed wiring board 601 (FIG. 13 (f )reference).

FIG. 14 is a process diagram showing a method for producing a four-layer printed wiring board (corresponding to Example 13 described later) centering on a polyimide resin layer similar to FIG.

[0090] First, a double-sided copper-clad laminate 702 in which a polyimide resin layer is used as an insulating layer and copper foils 703-1 and 703-2 are laminated on both sides is prepared (see FIG. 14 (a)). As the double-sided copper-clad laminate 702, a commercially available double-sided copper-clad laminate can be used. Two double-sided copper-clad laminates 702 are prepared (the other one is indicated by reference numeral 702 '), and the wiring circuit layer 704— 1 ', 704-2 (see Fig. 14 (b)). In addition, the thickness of the polyimide resin layer, the wiring circuit layer (copper foil), etc. are preferably as described above.

[0091] On the other hand, the copper foil 706 on both sides of the double-sided copper-clad laminate 705 using the liquid crystal polymer layer 707 of the same size as the double-sided copper-clad laminates 702 and 702 'as the insulating layer is removed by etching and immersed in an alkali mixed aqueous solution. The liquid crystal polymer layer 707 is obtained by processing (see FIG. 14 (c)).

Next, the surface-treated liquid crystal polymer layer 707 is sandwiched between the double-sided copper-clad laminates 702 and 702 ′ facing each other in the wiring circuit layers 704-2 and 704-1 ′, and thermocompression bonded (FIG. 14). (See (d)). Na Reference numeral 708 indicates a hot platen. After heating and pressing, the substrate is cooled to obtain a laminate 709

(See Fig. 14 (e) and Fig. 14 (f)).

[0093] Next !, the obtained laminate 709 forms a through-hole 710 by a known method such as an NC drill (see FIG. 14 (g)), is subjected to desmear treatment, and has a panel mesh 711. (Fig. 14

(See (h)). Then, the outermost layer 712 is etched and patterned by a tenting method to form the wiring circuit layer 713, the solder resist layer 714, and the multilayer printed wiring board 7

01 can be obtained (see FIG. 14 (i)).

FIG. 15 is a process diagram showing a method for producing a four-layer printed wiring board (corresponding to Example 14 to be described later) having the same polyimide resin layer as that in FIG.

[0095] First, two double-sided copper clad laminates 802 and 802 ', which are wound in the form of a ring, in which a polyimide resin layer is used as an insulating layer and copper foils 803 and 803' are laminated on both sides thereof, are used. Prepare wiring circuit layers 804 and 804 ′ by any method to obtain double-sided wiring boards 805 and 805 ′ (see FIG. 15 (a)).

[0096] As the double-sided copper-clad laminates 802 and 802 ', commercially available double-sided copper-clad laminates can be used. The thicknesses of the polyimide resin layer and the wiring circuit layer (copper foil) are preferably as described above.

[0097] On the other hand, after removing the copper foil on both sides of the double-sided copper-clad laminate 806 having a liquid crystal polymer layer of the same size as the double-sided wiring boards 805 and 805 'as an insulating layer, the exposed surface is subjected to plasma treatment. As a result, a liquid crystal polymer layer 807 is obtained (see FIG. 15B).

Next, the surface-treated liquid crystal polymer layer 807 is sandwiched between the double-sided wiring boards 805 and 805 ′ with the wiring circuit layers 804 and 804 ′ facing each other, and thermocompression bonding is performed (see FIG. 15C). Reference numeral 808 indicates a roll. After heating and pressing, the substrate is cooled to obtain a laminate 809.

[0099] Next, in the obtained laminate 809, after cutting, through-holes 810 are formed by the same method as described above (see FIG. 15 (d)), desmear treatment is performed, and a panel member is obtained. Form 811. Then, the outermost layer 812 is etched and patterned by a tenting method to form a wiring circuit layer 813 and further a solder resist layer 814 to obtain a multilayer printed wiring board 801 (FIG. 15 ( e), see Figure 15 (f)).

FIG. 16 is a process diagram showing a method for producing an 8-layer printed wiring board (corresponding to Example 15 described later) centering on a polyimide resin layer. [0101] First, two double-sided copper clad laminates 902 in which a polyimide resin layer is used as an insulating layer and copper foils 903-1 and 903-2 are laminated on both sides are prepared (see FIG. 16 (a), Here, only the double-sided copper-clad laminate 902 is displayed.) ₀ Double-sided copper-clad laminates 902 and 902 ′ can be commercially available double-sided copper-clad laminates. Wiring circuit layers 904-1, 904-1 ', 904-2, 904-2' are formed on both sides of this double-sided copper-clad laminate 902, 902 'by any method (see Fig. 16 (b)). . The thicknesses of the polyimide resin layer and the wiring circuit layer (copper foil) are preferably as described above.

[0102] On the other hand, the copper foil 906 on both sides of the double-sided copper-clad laminate 905 using the liquid crystal polymer layer 907 of the same size as the double-sided copper-clad laminate 902, 902 'as an insulating layer is etched away and immersed in an aqueous alkali mixture The liquid crystal polymer layer 907 is obtained by processing (see FIG. 16 (c)).

Next, the surface-treated liquid crystal polymer layer 907 is sandwiched between the double-sided copper-clad laminates 902 and 902 ′ formed with a circuit as described above, and thermocompression bonded (see FIG. 16 (d)). Reference numeral 90 8 indicates a hot platen. Thereafter, after heating and pressing, the substrate is cooled to obtain a laminate 909 (see FIG. 16 (e)).

[0104] Next, single-sided copper-clad laminates 910 and 910 'were prepared by plasma-treating the resin surfaces 911 and 911' of the liquid crystal polymer, and the resin surfaces 911 and 911 'were opposed to both sides of the laminate 909. Are stacked (see Fig. 16 (f)), heated and pressurized to obtain laminate 912 (see Fig. 16 (g)).

Next, the obtained stacked body 912 is etched 913 (see FIG. 16 (h)), and then a blind via hole 914 is formed (see FIG. 16 (i)). After the desmear treatment, a plating layer 915 is formed (see FIG. 16 (j)), and a wiring circuit layer 916 is formed (see FIG. 16 (k)). Steps (f) to (i) in FIG. 16 are performed again, through holes 918 are formed in the obtained laminate 917 (see FIG. 16 (1)), desmear treatment is performed, and panel fittings 919 are formed. (See Fig. 16 (m)). Then, the outermost layer 920 is etched and turned by a tenting method to form a wiring circuit layer 919 and a solder resist layer 921 to obtain an eight-layer printed wiring board 901 (see FIG. 16 (n)).

FIG. 17 is a process diagram showing a method for producing an 8-layer printed wiring board (corresponding to Example 16 to be described later) centering on a polyimide resin layer similar to FIG.

[0107] First, a polyimide resin layer is used as an insulating layer, and copper foils 1003-1, 1003-2, 1003 are formed on both sides thereof.

Prepare two-sided double-sided copper-clad laminates 1002 and 1002 'wound in a roll with 1' and 1003-2 'layers, and use any method for wiring circuit layers 1004—1, 1004—2, 1004 —1 ', 10 04—2 ′ is formed, and double-sided wiring boards 1005 and 1005 ′ are obtained (see FIG. 17 (a)). As the double-sided copper-clad laminates 1002 and 1002 ′, a commercially available double-sided copper-clad laminate can be used. The thicknesses of the polyimide resin layer and the wiring circuit layer (copper foil) are preferably as described above.

[0108] On the other hand, the copper foil on both sides of the double-sided copper clad laminate 1006 having the same size liquid crystal polymer layer as the double-sided wiring boards 1005 and 1005 'as the insulating layer is removed by etching, and then the surface is subjected to plasma treatment and the liquid crystal polymer Layer 1007 is obtained (see Fig. 17 (b)).

Next, the surface-treated liquid crystal polymer layer 1007 is sandwiched between the double-sided wiring boards 1005 and 1005 ′, heat-pressed and then cooled to obtain a laminate 1009 (see FIG. 17 (c)). Reference numeral 1008 indicates a roll.

[0110] Next, a single-sided copper-clad laminate 1 010, 1010 'in which the resin surfaces of the liquid crystal polymers 1011, 1011' were plasma-treated was prepared, and the liquid crystal positors 1011, 1011 'were put on both sides of the laminate 1009 The laminates 1012 are obtained by stacking the surfaces facing each other and heating and pressing (see FIG. 17 (d)).

[0111] Next, the laminated body 1012 is etched 1014, and then the blind via hole 1015 is formed (see FIG. 17 (e)). After the desmear treatment, a plating layer 1016 electrically connected to the wiring circuit layers 1004-1 and 1004-2 'is formed (see Fig. 17 (f)), and further, the wiring circuit layer 1017 is formed (Fig. 17 (g )reference). The steps from Fig. 17 (c!) To (e) are carried out again, through holes 1019 are formed in the obtained laminate 1018 (see Fig. 17 (h)), desmear treatment is performed, and panel fittings 1020 (See Fig. 17 (i)). Then, the outermost layers 1021 and 1021 are etched and patterned by a tenting method to form a wiring circuit layer 1022 and a solder resist layer 1023 to obtain an eight-layer printed wiring board 1001 (see FIG. 17 (j)). .

Example

[0112] Hereinafter, the present invention will be described more specifically based on Examples and Comparative Examples, but the present invention is not limited to the following Examples.

[0113] (Example 1)

A first insulating layer 12 made of a first liquid crystal polymer having a melting point of 295 ° C. (thermal deformation temperature: 265 ° C.) having a thickness of 25 μm and a thickness laminated on both surfaces of the first insulating layer 12 Etching resist lamination, exposure, development, etching, and resist stripping are performed on a copper clad laminate 14 with 9m copper foil 10 and a roll 'toe' roll method, and wiring circuit 16 is provided on both sides. form Thus, a long wiring board 18 wound in a roll shape having a width of 300 mm and a length of 200 m was produced (see FIG. 1).

[0114] Next, a second insulating layer 22 made of a second liquid crystal polymer having a melting point of 280 ° C (thermal deformation temperature: 240 ° C) and having a thickness of 25 µm, and a second insulating layer 22 Prepare a two-layer conductor layer substrate 24 having a conductor layer 20 (copper foil) with a thickness of 9 μm laminated on one side (see Fig. 2). Each of the 22 surfaces was plasma treated.

[0115] Then, the wiring board 18 and the two conductor layer boards 24 are pulled out, respectively, and the two conductor layer boards 24 are directed to the wiring board 18 with the wiring board 18 in between. Using a roll laminator as the heat and pressure treatment equipment 27, a multilayer printed wiring board whose outermost surface is unprocessed is continuously heated and pressurized under the conditions of a roll temperature of 260 ° C and a roll linear pressure of 20 kNZm. (Laminated body 26) was produced (see FIG. 3).

[0116] Next, the obtained laminate 26 was cut to 300 mm x 400 mm, and a through hole 30 of φ0.15 mm was formed with an NC drill cage (see Fig. 5 (a)), and after a predetermined desmear treatment 8 m thick panel mesh 32 was applied (see Fig. 5 (b)). Then, the outermost surface was etched and patterned by the tenting method to form the outermost wiring circuit 34, and further the solder resist 36 was formed to produce a multilayer printed wiring board 38 (see FIG. 5 (c)). ).

[0117] In the obtained multilayer printed wiring board, it was confirmed that deformation of the outermost wiring circuit 34 can be sufficiently prevented. Further, when the cross-section of the obtained laminate 26 was observed, no disconnection or deformation of the wiring circuit 16 of the wiring circuit 16 was observed, and the filling of the second liquid crystal polymer 22 between the wirings was good. The fat layer thickness was also substantially uniform.

[0118] (Example 2)

The multilayer printed wiring board obtained in Example 1 was further multilayered as follows. That is, first, a multilayer printed wiring board (laminate 26) whose outermost surface obtained in Example 1 was not processed was prepared, and upper and lower double-sided copper foils 20 were patterned to form a wiring layer (wiring circuit). . Next, a second insulating layer 22 having a thickness of 260 μC (thermal deformation temperature: 220 ° C) and having a second liquid crystal polymer force and having a thickness of 25 μm is laminated on one side of the second insulating layer 22. Two conductor layer substrates 24 having a conductor layer 20 (copper foil) having a thickness of 9 μm were prepared (see FIG. 2).

[0119] Then, a multilayer printed wiring board (laminated body 26 on which a wiring layer is formed) and two conductor layer substrates 2 4 with a multilayer printed wiring board (laminated body 26 with a wiring layer formed) in between, the two conductor layer substrates 24 are respectively disposed on the second insulating layer side with a multilayer printed wiring board (laminated with a wiring layer formed). Placed toward the body 26), using a roll laminator as the heat and pressure treatment equipment 27, continuously heated and pressurized under the conditions of a roll temperature of 240 ° C and a roll linear pressure of 20kNZm, a multilayer printed wiring board ( Two conductor layer substrates 24 were laminated on the laminate 26) on which the wiring layer was formed. Thereafter, a post-process as shown in FIG. 5 was performed to further increase the number of layers of the multilayer printed wiring board (laminated body 26 on which a wiring layer was formed).

[0120] (Example 3)

A copper having a first insulating layer 12 having a thickness of 25 m and a copper foil 10 having a thickness of 9 m laminated on both surfaces of the first insulating layer 12, which also has a first liquid crystal polymer force having a melting point of 295 ° C. Etching resist lamination, exposure, development, etching, and resist stripping are performed on the tension laminate 14 by the roll 'toe' roll method, wiring circuit 16 is formed on both sides, and the roll is 300mm wide and 200m long. A long wiring board 18 wound in a shape was produced (see FIG. 1).

[0121] Next, the second insulating layer 22 having a thickness of 25 μm and the second liquid crystal polymer having a melting point of 280 ° C., and the thickness laminated on one side of the second insulating layer 22 is 9 μm. A two-conductor layer substrate 24 having m conductor layers 20 (copper foil) was prepared (see FIG. 2).

[0122] Then, the wiring board 18 and the two conductor layer boards 24 are respectively pulled out, and the two conductor layer boards 24 are directed to the wiring board 18 with the wiring board 18 therebetween. Using a roll laminator as the heat and pressure treatment equipment 27, the laminate (temporary laminate) 26 is produced by continuously heating and pressing under the conditions of a roll temperature of 210 ° C and a roll linear pressure of lOOkNZm. (See Figure 3). The peel strength at the laminate interface of the obtained temporary laminate 26 was 0.2 kNZm, and it was not peeled when wound up into a roll, but could be easily peeled off by hand.

[0123] Next, the obtained temporary laminate 26 was subjected to high-temperature heat treatment at 280 ° C for 30 seconds using a heat treatment equipment 29 to produce an outer layer unprocessed multilayer printed wiring board 28 (see Fig. 4). ). The peel strength at the laminated interface of the obtained outer layer unprocessed multilayer printed wiring board 28 was 0.8 kNZm, which was not easy to peel off by hand.

[0124] Next, the obtained outer layer unprocessed multilayer printed wiring board 28 was cut into 300 mm x 400 mm. A through hole 30 of φ θ. 15mm was formed by NC drilling (see Fig. 5 (a)), and after a predetermined desmear treatment, panel plating 32 of 8 / zm thickness was applied (see Fig. 5 (b)) . Then, the outermost surface was etched and patterned by the tenting method to form the outermost wiring circuit 34, and further the solder resist 36 was formed to produce a multilayer printed wiring board 38 (see FIG. 5 (c)). See).

[0125] At this time, when the obtained multilayer printed wiring board 38 was cut into a size of 5 cm square, the wiring board warpage was evaluated, and the wiring board warpage was small. In addition, when the cross-section of the obtained outer layer unprocessed multilayer printed wiring board 28 was observed, the wiring circuit 16 was not disconnected or deformed, and the second liquid crystal polymer 22 was well filled between the wirings. The thickness of each resin layer was also substantially uniform.

[0126] (Example 4)

Instead of the copper-clad laminate used in Example 3, the thickness is laminated on both surfaces of the first insulating layer 12 and the first insulating layer 12 having a thickness of 25 m made of polyimide having a heat distortion temperature of 360 ° C. An outer layer unprocessed multilayer printed wiring board 28 and a multilayer printed wiring board 38 were produced in the same manner as in Example 3 except that a copper clad laminate having a 9 μm copper foil 10 was used.

[0127] At this time, the peel strength at the lamination interface of the obtained temporary laminate 26 is 0.2 kNZm, and it does not peel when wound into a roll, but can be easily peeled off by hand. Atsuta. Further, the peel strength at the lamination interface of the obtained outer layer unprocessed multilayer printed wiring board 28 was 0.9 kNZm, and it was not easily peeled off by hand.

[0128] Further, when the obtained multilayer printed wiring board 38 was cut into a size of 5 cm square, the wiring board warpage was evaluated, and the wiring board warpage was small. Further, when a cross-sectional observation of the obtained outer layer unprocessed multilayer printed wiring board 28 was performed, no disconnection or deformation of the wiring circuit 16 was observed, and the filling of the second liquid crystal polymer 22 between the wirings was also good. The thickness of each resin layer was also substantially uniform.

[Example 5]

The roll laminator roll temperature was 275 ° C, the linear pressure was 20 kNZm, and the high-temperature heat treatment as shown in Fig. 4 was not performed. A printed wiring board 38 was produced. [0130] At this time, the peel strength at the lamination interface of the obtained outer layer unprocessed multilayer printed wiring board 28 was 0.6 kN / m. However, when the obtained multilayer printed wiring board 38 was cut into a 5 cm square size, the wiring board warpage was evaluated. Further, when a cross-sectional observation of the obtained outer layer unprocessed multilayer printed wiring board 28 was performed, a minute deformation of the wiring circuit, which seems to be caused by stress at the time of lamination, was confirmed.

[0131] (Reference Example 1)

A temporary laminate 26 was produced in the same manner as in Example 3 except that the roll temperature of the roll laminator was 170 ° C. and the linear pressure was 100 kN / m.

[0132] At this time, the obtained temporary laminate 26 was easily peeled off at the lamination interface, and was unable to be wound into a roll. Therefore, it cannot be used as a temporary laminate, and it was impossible to carry out the subsequent steps after the high-temperature heat treatment.

[0133] (Reference Example 2)

The outer layer unprocessed multilayer printed wiring board 28 and the multilayer printed wiring board 38 were produced in the same manner as in Example 4 except that the processing temperature in the high temperature heat treatment was 250 ° C. and the processing time was 30 seconds.

[0134] At this time, the peel strength at the laminated interface of the obtained outer layer unprocessed multilayer printed wiring board 28 was 0.3 kNZm, which can be easily peeled off by hand, and the adhesiveness is insufficient. It was something. Then, when the obtained multilayer printed wiring board 38 was cut into a size of 5 cm square, the wiring board warpage was evaluated, and the wiring board warpage was small.

[Example 6]

An outer layer unprocessed multilayer printed wiring board 28 and a multilayer printed wiring board 38 were produced in the same manner as in Example 4 except that the processing temperature in the high temperature heat treatment was 310 ° C. and the processing time was 30 seconds.

[0136] At this time, the peel strength at the lamination interface of the obtained outer layer unprocessed multilayer printed wiring board 28 was 0.9 kNZm, and it was not easily peeled off by hand. However, when the obtained multilayer printed wiring board 38 was cut into a size of 5 cm square, the wiring board warpage was evaluated. In addition, when the cross-section of the resulting outer layer unprocessed multilayer printed wiring board 28 was observed, it was thought to be due to thermal deformation during high-temperature heat treatment. As a result, the deformation of the circuit was confirmed.

[0137] <Evaluation results of peel strength, warpage and cross-section observation of multilayer printed wiring board>

Peel strength (peel) at the lamination interface between the temporary laminate obtained in Examples 3 to 6 and Reference Examples 1 and 2 and the outer layer unprocessed multilayer printed wiring board, evaluation of warpage of the multilayer printed wiring board, and outer layer not yet Table 1 shows the results of evaluation or measurement of cross-section observation of processed multilayer printed wiring boards. Table 1 shows the material type of the first insulating layer in Examples 3 to 6 and Reference Examples 1 and 2, and the conditions for temporary lamination and high-temperature heat treatment.

[0138] [Table 1]

As is clear from the results shown in Table 1, after the wiring board 18 and the conductor layer board 24 were laminated (temporary laminated) under a specific heating and pressing to obtain a laminated body 26 (temporary laminated body 26). When the laminated body 26 is subjected to high-temperature heat treatment by heating it under specific conditions using a heat treatment equipment 29 to obtain an outer layer unprocessed multilayer printed wiring board 28 (Examples 3 and 4), A wiring circuit formed on the outermost surface of a multilayer printed wiring board in a method of manufacturing a multilayer printed wiring board having an insulating layer that also has liquid crystal polymer power continuously by a roll method. It was confirmed that warpage of the multilayer printed wiring board can be sufficiently suppressed.

[0140] (Example 7)

The multilayer printed wiring board 101 whose sectional view is shown in FIG. 8 will be described.

[0141] The multilayer (four-layer) printed wiring board 101 shown in FIG. 8 has a basic structure 105 in which one polyimide resin layer 103 and two liquid crystal polymer layers 104 are used as insulating layers. A wiring circuit layer 102 is formed on both sides of the resin layer 103, and further, a liquid crystal polymer layer 104 is provided on both sides as an insulating layer. The polyimide resin layer 103 and the wiring circuit layer 102 on both sides are made of a double-sided copper-clad laminate (manufactured by Nippon Steel Chemical Co., Ltd., trade name: Esbanex S (espanex is a registered trademark), product number: SB12— 25—12CE) force is also formed. That is, the polyimide resin layer 103 is a polyimide resin layer derived from the double-sided copper-clad laminate, and the wiring circuit layer 102 was formed by processing a copper foil derived from the double-sided copper-clad laminate. Is.

[0142] In the multilayer printed wiring board 101 shown in Fig. 8, the liquid crystal polymer layer 104 as the basic structure 105 and the wiring circuit layer 109 provided adjacent thereto are formed by, for example, processing the double-sided copper-clad laminate. A single-sided copper-clad laminate (hereinafter referred to as a single-sided copper-clad laminate) having a 12-m-thick copper foil on one side of a 25-m-thick insulating layer on both sides of the double-sided wiring board obtained LX, a melting point of liquid crystal polymer: 280 ° C), can be formed by laminating and forming a copper foil circuit. As shown in FIG. 8, the wiring circuit layer 109 has a wiring circuit layer 106 on the surface thereof, a through hole 107 for electrically connecting each layer, and a solder resist layer 108 formed in the outermost layer. Have! /

Here, the wiring circuit layer 106 is composed of the same copper 110 as the wiring circuit layer 109 and the fitting through hole 107. The liquid crystal polymer layer 104 has a thickness of 25 m, the wiring circuit layer 109 has a thickness of 12 μm, and the polyimide resin layer 103 has a thickness of 25 μm. The through hole 107 has a hole diameter of 0.15 mm, the plated copper 110 has a thickness of 8 m, and the solder resist layer 108 has a thickness of 25 m. The basic design rule for the wiring circuit layer is that the wiring circuit layer 102 is line Z space: 50/50 μm, wiring circuit layer 106 force 75Z75 μm, through-hole land of each wiring circuit layer 102, 106 force φ 0.3 mm It is. In addition, polyimide resin layer 103 and two liquids As a result of cross-sectional observation, the roughness (Rz) of the two boundary surfaces 112 and 112 formed between the crystalline polymer layers 104 and 104 was 4.5 m and 4.9 m, respectively. The total thickness of the four-layer printed wiring board 101 was about 125 μm.

[Example 8]

A multilayer printed wiring board 201 whose sectional view is shown in FIG. 9 will be described.

[0145] A multilayer (four-layer) printed wiring board 201 shown in Fig. 9 uses two polyimide resin layers 203, 203 and one liquid crystal polymer layer 204 as an insulating layer. Wiring circuit layers 208 and 208 ′ are formed on both sides of the oil layers 203 and 203 ′, and the liquid crystal polymer layer 204 is used as an insulating layer between the polyimide resin layer 203 and the polyimide resin layer 203 ′. have. Polyimide resin layer 203 and wiring circuit layers 208 and 208 'on both sides are made of double-sided copper-clad laminate (manufactured by Nippon Steel Chemical Co., Ltd., trade name: Esbanex M, product number: MB12-12-12FR) It is formed from. That is, the polyimide resin layers 203 and 203 'are polyimide resin layers derived from the double-sided copper-clad laminate, and the wiring circuit layers 208 and 208' are circuited copper foils derived from the double-sided copper-clad laminate. It is formed by processing.

[0146] The basic structure 205 of the multilayer printed wiring board 201 shown in FIG. 9 is a circuit processing only on one side of a double-sided copper-clad laminate having polyimide resin layers 203 and 203 'as insulating layers on both sides of the liquid crystal polymer layer 204. The wiring circuit layers 202-2 and 202-1 ′ thus formed and the liquid crystal polymer layer 204 were laminated and integrated so that the outer wiring circuit layer 208 was formed. Here, the liquid crystal polymer layer 204 has a double-sided copper-clad laminate (hereinafter referred to as double-sided copper-clad laminate) having a liquid crystal polymer layer with a thickness of 50 m as an insulating layer and a copper foil with a thickness of 12 / zm on both sides. A liquid crystal polymer film obtained by etching away a copper foil having a melting point of 300 ° C. (referred to as plate LY) was used. As shown in FIG. 9, the outer wiring circuit layer 208 has a wiring circuit layer 209 on the surface thereof, and a through hole 206 for electrically connecting each layer and a solder formed in the outermost layer. It has a resist layer 207!

[0147] Here, the wiring circuit layers 202-1 and 202-2 'are the wiring circuit layer 208 derived from the double-sided copper clad laminate LY (manufactured by Nippon Steel Engineering Co., Ltd., trade name: ESPANEX M Part No .: MB12-12-12F R), and the plated through-hole 206 and the same plated copper 209. The thickness of the polyimide resin layer is 12 μm, and the thickness of the copper foil derived from Esbanex M is 12 μm. Also, The hole diameter of one hole 206 is 0.15 mm, the thickness of plated copper 209 is 8 m, and the thickness of the solder resist film is 20 m. The basic design rule for the wiring circuit layer is that the wiring circuit layers 202-2 and 202-1 are line Z space: 50Z50 μm, the wiring circuit layers 202-1 and 202-2 are line Z space: 75Z75 μm, The through hole land of each layer is φ0.3mm. The roughness (Rz) of the interface 210 between the polyimide resin layers 203 and 203 ′ and the liquid crystal polymer layer 204 was 2.0 m and 1.9 m, respectively, as a result of cross-sectional observation. The total thickness of the four-layer printed wiring board 201 was about 115 m.

[Example 9]

A multilayer printed wiring board 301 whose sectional view is shown in FIG. 10 will be described.

[0149] A multilayer (8-layer) printed wiring board 301 shown in FIG. 10 has a basic structure 302 similar to that of Example 2 (but no structure corresponding to the through-hole 206 and its plated copper 209). Laminated liquid crystal polymer layers 303 and 303, IVH304 ', self-wire circuit layers 305 and 305, and liquid crystal polymer layers 317 and 317', BVH307 and 307 ', and wiring circuit layers 308 and 308' It is an eight-layer printed wiring board that is integrated with a through hole 309 that electrically connects each layer and a solder resist layer 310 formed as the outermost layer.

[0150] The liquid crystal polymer layers 303 and 303 'are made of a single-sided copper-clad laminate (hereinafter referred to as a single-sided copper-clad laminate) having a 25-m-thick liquid crystal polymer as an insulating layer and a copper foil of 9 m thickness on one side. This is a plate LX2, which is derived from the melting point of the liquid crystal polymer: 300 ° C., and the wiring circuit layers 311 and 311 ′ are formed by circuit processing of the copper foil of the single-sided copper-clad laminate. In addition, the liquid crystal polymer layers 317 and 317 ′ have a single-sided copper-clad laminate (hereinafter referred to as single-sided copper-clad laminate) having a liquid crystal polymer with a thickness of 50 m as an insulating layer and a copper foil with a thickness of 9 μm on one side. Laminated plate LX3 is derived from the melting point of liquid crystal polymer: 280 ° C., and the wiring circuit layers 313 and 313 ′ are formed by circuit processing the copper foil of the single-sided copper-clad laminate. The IVH 304 ′ is arbitrarily provided by a known means, and can be electrically connected to other wiring circuits.

[0151] Here, the self-wire circuit layers 305 and 305 are composed of the self-wire circuit layers 311 and 311 and the plated copper 312 that is the same as the IVH 304 and 304. Similarly, the wiring circuit layers 308, 308 ′ are composed of the wiring circuit layers 313, 313, BVH 307, 307, and the same copper copper 314 as that of the female snowboard motor 309. [0152] The liquid crystal polymer thickness derived from single-sided copper-clad laminate LX2 and single-sided copper-clad laminate LX3 is 25 / zm, and the thickness of wiring circuit layers 313 and 313 'is 9 / zm. IVH304', BVH307, 307 ' The upper diameter is 100 μm, the lower diameter is 90 μm, the thickness of plated copper 314 is 8 μm, the diameter of through hole 30 9 is 0.15 mm, the thickness of plated copper 312 is 8 m, and the solder resist layer 310 The film thickness is 20 m. The basic design rule for the wiring circuit layer is that the wiring circuit layers 305 and 305 have a line / space of 50/50 μm in all layers, the through-hole land 315 has a total layer of 0.3 mm, IVH30 4, and BVH307 and 307. Nodka 2 mm. The roughness (Rz) of the interface 316 between the polyimide resin layer and the liquid crystal polymer layer was 2.2 m and 2.0 m as a result of cross-sectional observation. The total thickness of this 8-layer printed wiring board 301 was about 270 m.

[Example 10]

A multilayer printed wiring board 401 whose sectional view is shown in FIG. 11 will be described.

[0154] The multilayer (four-layer) printed wiring board 401 shown in Fig. 11 has one polyimide resin layer 40 3 and two liquid crystal polymer layers 404 and 407 in an insulating layer, and four wiring circuit layers. 402, 406, 412, 41 4. The polyimide resin layer 403 and the wiring circuit layers 402 and 414 on both sides thereof are double-sided copper-clad laminates made of polyimide resin layer as an insulating layer (manufactured by Nippon Steel Chemical Co., Ltd., trade name: ESPANEX) S, product number: SB 18-25-18CE) is a wiring circuit layer formed by applying a circuit to the resin layer and its copper foil. The liquid crystal polymer layer 404 and the wiring circuit layer 406 adjacent to the polyimide resin layer 403 are a single-sided copper-clad laminate (hereinafter referred to as a single-sided copper clad laminate having an 18-m thick copper foil on one side of an insulating layer of a liquid crystal polymer layer having a thickness of 50 m) This is called single-sided copper-clad laminate LX4, which is derived from the melting point of the liquid crystal polymer: 290 ° C, and the liquid crystal polymer layer 407 and the wiring circuit layer 412 adjacent to the liquid crystal polymer layer 404 have a thickness of 50 Derived from a single-sided copper-clad laminate (hereinafter referred to as single-sided copper-clad laminate LX5; melting point of liquid crystal polymer: 280 ° C), which has a copper foil of thickness on one side of the insulating layer of the liquid crystal polymer layer of m It is a wiring circuit layer formed by circuit processing of a resin layer and its copper foil. The wiring circuit layer 408 includes the wiring circuit layer 412 and the BVH 409 and the plated copper 413 identical to the plated through hole 410, and the wiring circuit layer 402 ′ includes the wiring circuit layer 414 and the mating copper 413.

[0155] Here, the liquid crystal polymer thickness of the single-sided copper-clad laminate LX4 and single-sided copper-clad laminate LX5 is 50 μm, the thickness of the self-wire circuit layers 406 and 412 ί or 18 μm, and the polyimide layer 403 thickness ί or 25 μ m, and the thickness of the wiring circuit layers 402 and 408 is 18 μm. Also, the hole diameter of the through hole 410 is 0.15 mm, the upper diameter of the BVH409 is 80 m, the lower diameter is 75 / ζ πι, the thickness of the copper 413 is 8 μm, the solder resist layer 411 The film thickness is 20 μm. The roughness (Rz) of the interface 415 between the polyimide resin layer 403 and the liquid crystal polymer layer 404 was 4.Ίμι and 4.6 μm, respectively, as a result of cross-sectional observation. The total thickness of this 4-layer printed wiring board 401 was about 168 μm.

[Example 10]

A manufacturing method of the four-layer printed wiring board 501 having the same structure as the four-layer printed wiring board of Example 7 will be described in detail with reference to the process cross-sectional views shown in FIGS.

[0157] First, a double-sided copper-clad laminate having an polyimide resin layer shown in Fig. 12 (a) as an insulating layer (manufactured by Nippon Steel Chemical Co., Ltd., trade name: Esbanex, product number: SB12-25) 12CE) 502 double-sided copper foil 503 was pattern-checked by the subtractive method to produce a 400 x 300 mm double-sided wiring board 505 with a wiring circuit layer 504 (see Fig. 12 (b)). Next, a single-sided copper-clad laminate LX506 of the same size with a liquid crystal polymer layer as an insulating layer was prepared, and the double-sided wiring board 505 was sandwiched from both sides facing each other and set in a vacuum press as it was (Fig. (See 12 (c)). Next, the mold was clamped while evacuating the press hot platen 507 at 1.3 kPa, and the hot platen was heated to 260 ° C and heated. Five minutes after the hot platen temperature reached 260 ° C, an adhesive pressure of 6 MPa was applied, and 10 minutes later, cooling of the hot platen 507 was started (see Fig. 12 (d)). After 20 minutes, the adhesive pressure was removed, the heating plate 507 was opened, and the laminate 508 was taken out (see FIG. 12 (e)). Through hole 509 of φ 0.15mm is formed in the obtained laminate 508 with NC drill cage (see Fig. 12 (f)), and after the desmear treatment, 8 / zm thick panel 510 is formed. (See Fig. 12 (g)). Then, the outermost layer 511 was etched and patterned by a tenting method, a wiring circuit layer 512 was formed, and a solder resist layer 513 was formed to produce a four-layer printed wiring board 501 (see FIG. 12 (h)).

[0158] The yield loss due to powder falling in this process was 0%.

[Example 12]

Another method for manufacturing a four-layer printed wiring board 601 having the same structure as that of the four-layer printed wiring board of Example 11 will be described in detail with reference to process cross-sectional views shown in FIGS. 13 (a) to (f). [0160] First, a copper foil 603 on both sides of the same double-sided copper-clad laminate 602 used in Example 11 was patterned by a subtractive method to form a wiring circuit layer 604, width 300 mm, length 100 m. A long double-sided wiring board 605 wound in a roll was prepared (see FIG. 13 (a)). A double-sided wiring board 605 is sandwiched between LX606, a single-sided copper-clad laminate with the same shape facing the grease surface from both sides (see Fig. 13 (b)), and supplied between rolls 607 with a surface temperature of 260 ° C. Was heated and pressurized at a linear pressure of 20 kNZm (see Fig. 13 (c)). The obtained continuous laminate 608 was cut to 400 X 30 mm, and a through hole 609 of φ0.15 mm was formed with an NC drill cage (see Fig. 13 (d)). A panel fitting 610 having a thickness of zm was formed (see FIG. 13 (e)). Then, the outermost layer 611 was etched and patterned by a tenting method to form a wiring circuit layer 612, and a solder resist layer 613 to form a four-layer printed wiring board 601 (see FIG. 13 (f)).

[0161] The yield loss due to powder falling in this process was 0%.

[0162] (Example 13)

A method for manufacturing a four-layer printed wiring board 701 having the same structure as the four-layer printed wiring board of Example 8 will be described in detail with reference to process cross-sectional views shown in FIGS. 14 (a) to (i).

[0163] First, a double-sided copper-clad laminate with a 400 x 300mm polyimide resin layer as an insulating layer (manufactured by Nippon Steel Chemical Co., Ltd., trade name: Esbanex M, product number: MB12-12-12FR) 702 ( The copper foil 703-2 on one side in Fig. 14 (a) was pattern-checked by the subtractive method to form the wiring circuit layer 704-2. In the same manner, another sheet of double-sided copper-clad laminate 702 was pattern-carried (see Fig. 14 (b)). Then, both sides of the copper foil 706 of the double-sided copper-clad laminate LY705 that the insulating layer of the liquid crystal polymer layer of the same size is removed by etching, potassium hydroxide © beam the exposed surface (34 mass ^_0/0) Z Ethylene glycol ( 22 mass ^_0/0) (to prepare a 11 mass ⁰ / o) liquid crystal polymer layer 707 60 ° C, and 60 seconds immersed in an alkaline mixed aqueous solution of (FIG. 14 (c) Z Echirenjiamin reference). The surface-treated liquid crystal polymer layer 707 was sandwiched between single-sided processed substrates 70 2 and 702 'with the wiring circuit layer (704-2, 704-1') facing each other, and set in a vacuum press (Fig. 14 ( d)). Next, the mold was clamped while evacuating the press hot platen 708 at 1.3 kPa, and the hot platen 708 was heated to 300 ° C. and heated. 5 minutes after the hot platen temperature reached 300 ° C, 4 MPa pressure was applied, and 10 minutes later, the hot platen 708 started to cool (Fig. 14 (e) reference). After 20 minutes, the adhesive pressure was removed, the heating plate 708 was opened, and the laminate 709 was taken out (see FIG. 14 (f)). Through hole 710 of φ θ. 15 mm was formed on the obtained laminate 709 using an NC drill cage (see Fig. 14 (g)), and after a predetermined desmear treatment, a thick panel clasp 7 11 was formed ( (See Figure 14 (h)). Then, the outermost layer 712 was etched and patterned by a tenting method to form a wiring circuit layer 713, and further a solder resist layer 714 to form a four-layer printed wiring board 701 (see FIG. 14 (i)). ).

[0164] The yield loss due to powder falling in this process was 0%.

[Example 14]

Another method for manufacturing a four-layer printed wiring board 801 having the same structure as the four-layer printed wiring board of Example 13 will be described in detail with reference to the process cross-sectional views shown in FIGS.

[0166] First, a double-sided copper-clad laminate with a polyimide resin layer as an insulating layer (manufactured by Nippon Steel Engineering Co., Ltd., trade name: Esbanex M, product number: MB12-12-12FR) 802 , 802, copper foils 803, 803 'each side is patterned by subtractive method to form wiring circuit layers 804, 804' 30mm wide x 100m long rolled Double-sided wiring boards 805 and 805 'were fabricated (see Fig. 15 (a)). Next, the copper foil on both sides of the double-sided copper clad laminate LY806 with the same shape liquid crystal polymer layer as an insulating layer is removed by etching, and the exposed surface is plasma-treated using a gas composed of argon, helium, oxygen, and nitrogen. A liquid crystal polymer layer 807 was fabricated (see Fig. 15 (b)). This liquid crystal polymer layer 807 is sandwiched between two wiring boards 805 and 805 with the wiring circuit layers 804 and 804 'facing each other, and is supplied between rolls 8 08 having a surface temperature of 260 ° C, and continuously at a linear pressure of lOOkNZm. Heated and pressurized (see Fig. 15 (c)). The resulting continuous laminate 809ί, 400 X 300mm [Cutting, NC renoreka trowel [trowel φ 0.15mm through hole 810 (see Fig. 15 (d)), and after the prescribed desmear treatment 811 panel thickness 811 was formed (see Fig. 15 (e)). Then, the outermost layer 812 was etched and patterned by a tenting method, a wiring circuit layer 813 was formed, a solder resist layer 814 was formed, and a four-layer printed wiring board 801 was manufactured (see FIG. 15 (f)).

[0167] The yield loss due to powder falling in this process was 0%.

[Example 15]

The manufacturing method of 8-layer printed wiring board 901 with the same structure as the 8-layer printed wiring board of Example 9 is This will be described in detail with reference to process cross-sectional views shown in 16 (a) to (j).

First, a double-sided copper-clad laminate with a 400 x 300mm polyimide resin layer as an insulating layer (manufactured by Nippon Steel Chemical Co., Ltd., trade name: Esbanex M, product number: MB12-12-12FR) 902 (Fig. 16 ( The copper foils 903-1, 903-2 on both sides of a)) were pattern-checked by the subtractive method to form wiring circuit layers 904-1, 904-2. Similarly, another sheet was prepared (see Fig. 16 (b)). Next, the copper foil 906 on both sides of the double-sided copper clad laminate LY905 having the same size liquid crystal polymer layer as the insulating layer was removed by etching, and the exposed surface was hydrated with potassium hydroxide (34% by mass). 22 mass ^_0/0) (to prepare a 11 mass ⁰ / o) liquid crystal polymer layer 907 80 ° to C30 seconds immersed in an alkaline mixed aqueous solution of (FIG. 16 (c) Z Echirenjiamin reference). The surface-treated liquid crystal polymer layer 907 was sandwiched between the double-sided copper-clad laminates 902 and 902 'and set in a vacuum press as it was (see Fig. 16 (d)). Next, the mold was clamped while evacuating the press hot platen 908 at 1.3 kPa, and the hot platen 908 was heated to 280 ° C. and heated. Five minutes after the hot platen temperature reached 280 ° C, an adhesive pressure of 5 MPa was applied, and 10 minutes later, cooling of the hot platen 908 was started (see Fig. 16 (e)). Then, after 20 minutes, the adhesive pressure was removed, the heating platen 908 was opened, the laminate 909 was taken out, and the resin surface of the liquid crystal polymer was placed on both sides of the obtained laminate 909 with argon, helium, Single-sided copper-clad laminate LX2 910 and 910 'with 911 and 911' facing each other (see Fig. 16 (f)) and vacuumed under the above conditions. The laminate 912 was fabricated by pressing (see Fig. 16 (g)). The copper foil at a predetermined position of the laminate 912 was etched 913 to φ100 / zm (see Fig. 16 (h)), and then a blind via hole 914 was formed with a carbon dioxide laser (Fig. 16 (i)). reference). After the desmear treatment, a plating layer 915 electrically connected to the wiring circuit layer 904-2 ′ was formed (see Fig. 16 (j)), and a wiring circuit layer 916 was formed by the subtractive method (Fig. 16 (k)). reference). The steps from Fig. 11 (f) to (i) were carried out again, and a through hole 918 of φ θ. 15mm was formed in the resulting laminate 917 using an NC drill cage (see Fig. 16 (1)). After a predetermined desmear treatment, a panel 919 having a thickness of 8 / zm was formed (see FIG. 16 (m)). However, the single-sided copper-clad laminate LX3 was used as the newly laminated single-sided copper-clad laminate in FIG. 16 (1). Then, the outermost layer 920 was etched and turned by the tenting method, the wiring circuit layer 921 was formed, and the solder resist layer 922 was formed to produce an eight-layer printed wiring board 901 (see FIG. 16 (n)). ). [0170] The yield loss due to powder falling in this process was 0%.

[Example 16]

Another manufacturing method of the 8-layer printed wiring board 1001 having the same structure as the 8-layer printed wiring board of Example 15 will be described in detail with reference to process cross-sectional views shown in FIGS. 17 (a) to (f).

[0172] First, a double-sided copper-clad laminate with a polyimide resin layer as an insulating layer (manufactured by Nippon Steel Engineering Co., Ltd., trade name: Esbanex M, product number: MB12-12-12FR) 1002 , 1002, copper foils on both sides 1003-1, 1003-2, 1003-1 ', 1003-2' are turned by sub-rotative method, and wiring circuit layers 1004-1, 1004-2 1004-1 ′ and 1004-2-2 ′ were produced as long double-sided wiring boards 1005 and 1005 ′ wound in a roll shape having a width of 300 mm and a length of 100 m (see FIG. 17A). Next, the copper foil on both sides of the double-sided copper clad laminate LY1006 with the same shape liquid crystal polymer layer as the insulating layer is etched away, and the exposed surface is plasma using a gas such as argon, helium, oxygen, and nitrogen. A treated liquid crystal polymer layer 1007 was produced (see FIG. 17 (b)). The liquid crystal polymer layer 1007 sandwiched between two double-sided circuit board 1005, 1005 ', the surface temperature of 240 ^o to mouth one Honoré 1008f¾ [this supply and C, heated in a continuous [This line pressure 1 OOkNZm, pressurized (FIG. 17 (c)). Single-sided copper with an insulating layer of a 300 mm wide x 100 m long liquid crystal polymer layer that is plasma-treated on both sides of the resulting continuous laminate 1009 using a gas that also has argon, helium, oxygen, and nitrogen power Stretched laminates LX2 1010, 1010, the resin surfaces 1011, 1011 ′ were placed facing each other and continuously heated and pressurized under the above conditions to produce a continuous laminate 1012 (see FIG. 17 (d)). Next, an etching cache 1014 having a diameter of 100 m was formed at a predetermined position of the outermost copper foils 1013 and 1013 of the continuous laminated body 1012, and then blind via holes 1015 were cast with a carbonic acid laser (see FIG. 17 (e)). After the desmear treatment, a plating layer 1016 electrically connected to the wiring circuit layer 1004-2-2 'was formed (see Fig. 17 (f)), and a wiring circuit layer 1017 was formed by the subtractive method (Fig. 17 (g )reference). Again, the steps of Fig. 17 (d) to () were carried out, and through hole 1019 of φ θ. 15mm was formed in the obtained continuous laminate 1018 by NC drilling (see Fig. 17 (h)), and a predetermined desmear was formed. After processing, a thick panel fitting 1020 was formed (see Fig. 17 (i)), except that the single-sided copper-clad laminate LX3 was added to the newly laminated single-sided copper-clad laminate in Fig. 17 (h). After cutting to 400 mm x 300 mm, the outermost layers 1021 and 1021 were etched by the tenting method. Then, the wiring circuit layer 1022 was formed, the solder resist layer 1023 was formed, and the 8-layer printed wiring board 1001 was formed (see FIG. 17 (j)).

[0173] The yield loss due to powder falling in this process was 0%.

[0174] (Comparative Example 1)

Glass epoxy-based double-sided copper-clad laminate (made by Hitachi Chemical Co., Ltd., product name)

MCL—E—679, copper foil thickness: m, insulation base material thickness: 60 m)

In the same manner as in 11, a four-layer substrate having a total thickness of 190 / zm was produced. The yield loss due to powder falling in this process was 4.5%.

[0175] (Comparative Example 2)

In Example 12, instead of the single-sided copper-clad laminate LX, a copper foil with grease (made by Matsushita Electric Works, trade name: R0880, copper foil thickness: m, grease thickness: 50 m) was used. The procedure was the same except that the temperature was changed to 180 ° C. However, since the copper foil with grease was broken during lamination, the four-layer printed wiring board could not be manufactured.

Industrial applicability

[0176] According to the present invention, in a method for continuously producing a multilayer printed wiring board having an insulating layer having a liquid crystal polymer power, deformation of the wiring circuit formed on the outermost surface of the multilayer printed wiring board is prevented. It is possible to provide a method for producing a multilayer printed wiring board that can be produced, and a multilayer printed wiring board obtained by the production method.

Claims

The scope of the claims

[1] A wiring board having a first insulating layer made of polyimide or a first liquid crystal polymer force and a wiring circuit formed on at least one side of the first insulating layer, and less than the thermal deformation temperature of the polyimide And a second insulating layer having a second liquid crystal polymer force having a melting point lower than that of Z or the first liquid crystal polymer and a conductor layer laminated on one side of the second insulating layer. A step of preparing a conductor layer substrate having,

A method for producing a multilayer printed wiring board, comprising:

[2] Two conductor layer substrates are prepared, and when the wiring substrate and the conductor layer substrate are laminated, the wiring substrate and the two conductor layer substrates are sandwiched between the two substrates. 2. The multilayer according to claim 1, wherein the conductor layer substrate is disposed with the second insulating layer side facing the wiring substrate, and is continuously laminated under heat and pressure using a heat and pressure treatment facility. Manufacturing method of printed wiring board.

[3] The method for producing a multilayer printed wiring board according to claim 1, wherein the second liquid crystal polymer has a melting point 5 to 60 ° C. lower than the melting point of the first liquid crystal polymer.

4. The method for producing a multilayer printed wiring board according to claim 1, wherein the wiring board and the conductor layer board are each wound in a roll shape.

[5] The multilayer print according to claim 4, wherein, when laminating the wiring board and the conductor layer board, the wiring board and the conductor layer board are respectively pulled out and continuously laminated by a roll 'toe' roll method. A method for manufacturing a wiring board.

6. The method for producing a multilayer printed wiring board according to claim 1, wherein the heat and pressure treatment facility is a roll laminator.

7. The method for producing a multilayer printed wiring board according to claim 6, wherein the roll line pressure of the roll laminator is 10 to 250 kNZm.

8. The method for producing a multilayer printed wiring board according to claim 1, further comprising a step of surface-treating a surface of the second insulating layer of the conductor layer substrate.

[9] In laminating the wiring board and the conductor layer board, the wiring board and the conductor layer board are laminated under heat and pressure to obtain a laminated body, and then the laminated body is subjected to heat treatment equipment. 2. The method for producing a multilayer printed wiring board according to claim 1, wherein high-temperature heat treatment is performed by heating.

[10] In performing the high-temperature heat treatment, the laminate is subjected to a high-temperature heat treatment temperature T that satisfies the condition represented by the following formula (F1):

The method for producing a multilayer printed wiring board according to claim 9, wherein heating is performed at

11. The method for producing a multilayer printed wiring board according to claim 10, wherein the high temperature heat treatment is performed in a range of 10 to 180 seconds when performing the high temperature heat treatment.

[12] In obtaining the laminate, the heat treatment temperature T for satisfying the condition represented by the following formula (F2) for the wiring board and the conductor layer board:

2

•. (F2)

The method for producing a multilayer printed wiring board according to claim 9, wherein the layers are laminated.

[13] In a multilayer printed wiring board in which wiring circuit layers and insulating layers are alternately laminated,

A multilayer print including a laminated structural unit in which one of the two insulating layers adjacent to each other through the wiring circuit layer is a polyimide resin layer, and the other insulating layer is a liquid crystal polymer layer. Wiring board.

[14] The liquid crystal polymer layer according to claim 13, wherein a liquid crystal polymer layer is further provided on the opposite side to the side adjacent to the polyimide resin layer of the liquid crystal polymer layer via a wiring circuit layer in the laminated structural unit. Multilayer printed wiring board.

15. The multilayer printed wiring board according to claim 13, wherein in the laminated structural unit, the roughness of the interface between the polyimide resin layer and the liquid crystal polymer layer is in the range of 4 to 6 m.

16. The multilayer printed wiring board according to claim 13, wherein in the laminated structural unit, the roughness of the interface between the polyimide resin layer and the liquid crystal polymer layer is less than 4 m.