JP7390846B2 - Rigid-flex multilayer printed wiring board and its manufacturing method - Google Patents
Rigid-flex multilayer printed wiring board and its manufacturing method Download PDFInfo
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- 229920005989 resin Polymers 0.000 claims description 98
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- 239000000758 substrate Substances 0.000 claims description 79
- 238000000034 method Methods 0.000 claims description 37
- 239000011248 coating agent Substances 0.000 claims description 28
- 238000000576 coating method Methods 0.000 claims description 28
- 239000000463 material Substances 0.000 claims description 15
- 238000010030 laminating Methods 0.000 claims description 6
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- 229910052751 metal Inorganic materials 0.000 description 12
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- 239000000853 adhesive Substances 0.000 description 4
- 230000001070 adhesive effect Effects 0.000 description 4
- 239000004744 fabric Substances 0.000 description 4
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- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 3
- 239000011889 copper foil Substances 0.000 description 3
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- 229920001187 thermosetting polymer Polymers 0.000 description 3
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 2
- 229910052802 copper Inorganic materials 0.000 description 2
- 239000010949 copper Substances 0.000 description 2
- ORTQZVOHEJQUHG-UHFFFAOYSA-L copper(II) chloride Chemical compound Cl[Cu]Cl ORTQZVOHEJQUHG-UHFFFAOYSA-L 0.000 description 2
- 239000013039 cover film Substances 0.000 description 2
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- JYLNVJYYQQXNEK-UHFFFAOYSA-N 3-amino-2-(4-chlorophenyl)-1-propanesulfonic acid Chemical compound OS(=O)(=O)CC(CN)C1=CC=C(Cl)C=C1 JYLNVJYYQQXNEK-UHFFFAOYSA-N 0.000 description 1
- 229910021578 Iron(III) chloride Inorganic materials 0.000 description 1
- 238000003848 UV Light-Curing Methods 0.000 description 1
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- RBTARNINKXHZNM-UHFFFAOYSA-K iron trichloride Chemical compound Cl[Fe](Cl)Cl RBTARNINKXHZNM-UHFFFAOYSA-K 0.000 description 1
- 238000003475 lamination Methods 0.000 description 1
- 229920001721 polyimide Polymers 0.000 description 1
- 239000012286 potassium permanganate Substances 0.000 description 1
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Description
本発明は、部品の実装が可能なリジッド領域と屈曲可能なフレキシブル領域とを備えたリジッド・フレックス多層プリント配線板及びその製造方法に関するものであり、特に、カメラモジュールなどのゴミの影響を受けやすい製品に使用できるリジッド・フレックス多層プリント配線板及びその製造方法に関する。 The present invention relates to a rigid-flex multilayer printed wiring board that has a rigid area on which components can be mounted and a flexible area that can be bent, and a method for manufacturing the same, and particularly relates to a rigid-flex multilayer printed wiring board that is easily affected by dust such as a camera module. The present invention relates to a rigid-flex multilayer printed wiring board that can be used in products and a method for manufacturing the same.
近年、自動車の自動制御化が益々進み、部品や各種センサの搭載点数が非常に多くなってきている。その結果、部品やセンサなどに用いられるプリント配線板においては、装置内への設置自由度の高さや、装置の小型化に寄与できるリジッド・フレックス多層プリント配線板の需要が高まっている。 In recent years, automatic control of automobiles has progressed more and more, and the number of mounted parts and various sensors has increased significantly. As a result, in printed wiring boards used for parts, sensors, etc., demand is increasing for rigid-flex multilayer printed wiring boards that have a high degree of freedom in installation within devices and can contribute to miniaturization of devices.
リジッド・フレックス多層プリント配線板は、現在、小型化や薄型化、高密度配線化などの観点から、図９に示すような製造方法によって製造されている（特許文献１及び２参照）。なお、図９においては、便宜上、フレキシブル基板の片側にのみ、リジッド基板を積層する例を示している。
即ち、フレキシブル基板６（図中の符号１は「フレキシブルベース基板」を示している）に形成された配線パターン２を保護するカバーレイ５として、表面に金属箔が積層された金属箔付きカバーレイを用い、当該金属箔をエッチング処理することによって、フレキシブル領域Ｆに相当する部分にレーザ受けパターン２５を設け、その後、リジッド基板のみからなる通常のビルドアップ多層プリント配線板の製造方法と同様に、絶縁樹脂層２３（例えば、厚さが２０～６０μｍからなるプリプレグ）と配線パターン２４とを交互に積層し、最後に外層の配線パターン２４を保護するソルダーレジスト１４を設けた後、フレキシブル領域Ｆ上に積層されている不要部２１をレーザ加工で刳り貫く、あるいは切削除去するという製造方法である。因みに、レーザ受けパターン２５は、不要部２１の除去後にエッチング除去される。
Rigid-flex multilayer printed wiring boards are currently manufactured by a manufacturing method as shown in FIG. 9 from the viewpoint of miniaturization, thinning, high-density wiring, etc. (see Patent Documents 1 and 2). Note that, for convenience, FIG. 9 shows an example in which a rigid substrate is laminated only on one side of a flexible substrate.
That is, as a coverlay 5 that protects a wiring pattern 2 formed on a flexible substrate 6 (numeral 1 in the figure indicates a "flexible base substrate"), a coverlay with metal foil on the surface of which a metal foil is laminated is used. A laser receiving pattern 25 is provided in the portion corresponding to the flexible region F by etching the metal foil using the following method, and then, as in the manufacturing method of a normal build-up multilayer printed wiring board consisting only of a rigid substrate, Insulating resin layers 23 (for example, prepreg with a thickness of 20 to 60 μm) and wiring patterns 24 are alternately laminated, and finally, after providing a solder resist 14 to protect the outer layer wiring patterns 24, a layer is formed on the flexible region F. This is a manufacturing method in which the unnecessary portions 21 stacked on the substrate are hollowed out or removed by laser processing. Incidentally, the laser receiving pattern 25 is removed by etching after the unnecessary portion 21 is removed.
このような製造方法を用いることにより、フレキシブル領域上の不要部を除去する工程までは、リジッド基板のみからなる通常のビルドアップ多層プリント配線板と同じ方法で製造できるため、小型化や薄型化、高密度配線化に優れたリジッド・フレックス多層プリント配線板を得ることができる。 By using this manufacturing method, up to the process of removing unnecessary parts on the flexible area, it can be manufactured in the same way as ordinary build-up multilayer printed wiring boards made only of rigid substrates, making it possible to reduce the size and thickness of the board. A rigid-flex multilayer printed wiring board with excellent high-density wiring can be obtained.
ところで、冒頭でも説明したように、リジッド・フレックス多層プリント配線板は、車載仕様品に多く使用されるようになってきているが、車載仕様品の場合、耐振動性などの観点から、厚さを０．８ｍｍ以上にして、剛性を確保するという条件が求められている。そのため、不要部２１をレーザ加工で除去するという図９に示した製造方法を、車載仕様品に適用することは難しいのが実状であった。
その理由は、リジッド基板１６の厚みが厚くなりすぎて、レーザ加工では、不要部２１を除去することができなくなってしまい、仮に、レーザの照射エネルギーを上げたとしても、今度は、レーザ受けパターン２５の下に位置するフレキシブル基板６にダメージを与えてしまう危険性が出てくるからである。
By the way, as explained at the beginning, rigid-flex multilayer printed wiring boards are increasingly being used for automotive specification products, but in the case of automotive specification products, the thickness There is a need to ensure rigidity by setting the diameter to 0.8 mm or more. Therefore, the actual situation is that it is difficult to apply the manufacturing method shown in FIG. 9, in which the unnecessary portion 21 is removed by laser processing, to an in-vehicle specification product.
The reason for this is that the thickness of the rigid substrate 16 has become too thick, making it impossible to remove unnecessary parts 21 by laser processing, and even if the laser irradiation energy is increased, the laser receiving pattern This is because there is a risk of damaging the flexible substrate 6 located under the substrate 25.
そこで、本発明者は、板厚が０．８ｍｍ以上の構成に対応すべく、図１０（ａ）及び（ｂ）に示したように、フレキシブル領域Ｆに対応する大きさのダミーパターン１９を備えた、厚さが１００μｍ以上のコア基材からなる厚み調節層８を内層側（フレキシブル基板６に近い側）に配置するとともに、当該厚み調節層８の上にビルドアップ層１５を積層し、その後、ダミーパターン１９の外周に沿うようにルータ加工（図１０（ａ）中の「スリット２２」参照）を行い、不要部２１を除去する方法を採れば、フレキシブル基板６へダメージを与えることなく不要部２１を除去できるとともに外層側を高密度配線化できると考え試みた。 Therefore, the present inventor provided a dummy pattern 19 with a size corresponding to the flexible region F, as shown in FIGS. In addition, a thickness adjustment layer 8 made of a core base material with a thickness of 100 μm or more is arranged on the inner layer side (the side closer to the flexible substrate 6), and a buildup layer 15 is laminated on the thickness adjustment layer 8, and then , by performing router processing along the outer periphery of the dummy pattern 19 (see "slit 22" in FIG. 10(a)) and removing the unnecessary part 21, the unnecessary part 21 can be removed without damaging the flexible substrate 6. An attempt was made based on the idea that the portion 21 could be removed and the outer layer side could be provided with high-density wiring.
その結果、不要部２１の除去は容易に行なえたものの、厚み調節層８におけるリジッド領域Ｒとフレキシブル領域Ｆの境界部に位置する側面壁８ｂ（図１０（ｂ）参照）から、樹脂の粉落ち（ゴミ）が多く発生してしまうという新たな問題が出てきた。
これは、厚み調節層８に含まれるガラスクロスの線径が、ビルドアップ層１５に積層される絶縁樹脂層のものと比べて太く、含浸される樹脂の量が多くなるため、ルータ加工面が荒れやすい傾向があることと、不要部２１を除去する際のルータ加工が、リジッド領域Ｒの製品エリアをなるべく広く確保するために、外形加工に用いられるルータビットよりも細径のものを用いて行なわれ、ルータビットの芯ブレが大きくなることが原因と考えられる。
As a result, although the unnecessary portion 21 was easily removed, resin powder fell off from the side wall 8b (see FIG. 10(b)) located at the boundary between the rigid region R and the flexible region F in the thickness adjustment layer 8. A new problem has arisen: a lot of (garbage) is generated.
This is because the wire diameter of the glass cloth included in the thickness adjustment layer 8 is thicker than that of the insulating resin layer laminated on the buildup layer 15, and the amount of resin impregnated is large, so the router processing surface is In order to ensure that the product area of the rigid region R is as wide as possible when removing unnecessary parts 21, a router bit with a smaller diameter than the router bit used for contour processing is used. This is thought to be due to the increased core wobbling of the router bit.
上記の問題に関して本発明者は、図１１に示したように、厚み調節層８におけるリジッド領域Ｒとフレキシブル領域Ｆの境界部に位置する側面壁８ｂを、加熱・積層プレスの際に絶縁樹脂層から流れ出る樹脂（図中の「被覆樹脂層１８ａ」に相当）によって被覆することで、当該側面壁からの粉落ち（ゴミ）を抑制できることを見い出し、既に特許出願している。
しかし、実際には、厚み調節層８の上下に位置する絶縁樹脂層（図中の「第一絶縁樹脂層７」と「第二絶縁樹脂層９」に相当）からも、ごく僅かに樹脂の粉落ち（ゴミ）が発生する場合があり、より高い品質が求められる製品に対しては、リジッド基板１６におけるリジッド領域Ｒとフレキシブル領域Ｆの境界部に位置する側面壁（ルータ加工面）１７（図１１参照）からの樹脂の粉落ち（ゴミ）を完全に無くす必要があった。
Regarding the above-mentioned problem, as shown in FIG. 11, the inventor of the present invention has solved the problem by adding an insulating resin layer to the side wall 8b located at the boundary between the rigid region R and the flexible region F in the thickness adjustment layer 8 during heating and lamination pressing. It has been discovered that powder falling (dust) from the side wall can be suppressed by coating it with a resin flowing out from the side wall (corresponding to the "coating resin layer 18a" in the figure), and a patent application has already been filed for this finding.
However, in reality, there is a very small amount of resin from the insulating resin layers located above and below the thickness adjustment layer 8 (corresponding to the "first insulating resin layer 7" and "second insulating resin layer 9" in the figure). For products that require higher quality due to the possibility of powder falling (dust), a side wall (router processing surface) 17 ( It was necessary to completely eliminate resin powder (dust) from the resin (see Figure 11).
樹脂の粉落ち対策としては、ディスペンサ等でインクを吹き付けて、側面壁１７を樹脂で被覆するという手段が考えられるが、ディスペンサ等で用いられるインクは、スクリーン印刷等に用いられるインクよりも粘度が低く、吹き付けたインクが、フレキシブル基板のフレキシブル領域Ｆ側に流れ込むことによって、当該フレキシブル領域の屈曲性を低下させてしまうという問題があった。 As a countermeasure against resin powder falling off, it is possible to spray ink with a dispenser or the like to cover the side wall 17 with resin, but the ink used in the dispenser or the like has a higher viscosity than the ink used in screen printing, etc. There is a problem in that the sprayed ink flows into the flexible region F side of the flexible substrate, thereby reducing the flexibility of the flexible region.
本発明は、上記の如き従来の問題に鑑みてなされたものであり、フレキシブル基板のフレキシブル領域の屈曲性を維持しながら、フレキシブル基板のリジッド領域に積層されるリジッド基板のリジッド領域とフレキシブル領域の境界部に位置する側面壁からの樹脂の粉落ち（ゴミ）の発生がないリジッド・フレックス多層プリント配線板及びその製造方法を提供することを課題とする。 The present invention has been made in view of the above-mentioned conventional problems, and it is possible to maintain the flexibility of the flexible region of the flexible substrate while also improving the rigid region and flexible region of the rigid substrate that is laminated on the rigid region of the flexible substrate. It is an object of the present invention to provide a rigid-flex multilayer printed wiring board and a method for manufacturing the same in which resin powder (dust) does not fall off from side walls located at the boundary.
本発明者は、上記の課題を解決すべく鋭意検討を重ねた結果、内層側に厚み調節層を備えたリジッド・フレックス多層プリント配線板を製造する過程で、厚み調節層の下に位置する絶縁樹脂層の一部がフレキシブル領域側へ突出した突出部が形成されることに着目し、当該突出部を、リジッド基板におけるリジッド領域とフレキシブル領域の境界部に位置するルータ加工面にインク（被覆用樹脂）を吹き付ける際のストッパーとして利用すれば、極めて良い結果が得られると考え、本発明を完成するに至った。 As a result of intensive studies to solve the above-mentioned problems, the present inventor discovered that, in the process of manufacturing a rigid-flex multilayer printed wiring board with a thickness adjustment layer on the inner layer side, the insulating material located under the thickness adjustment layer Focusing on the formation of a protrusion in which a part of the resin layer protrudes toward the flexible area, the protrusion was coated with ink (for coating) on the router processed surface located at the boundary between the rigid area and the flexible area of the rigid substrate. The present invention was completed based on the idea that extremely good results could be obtained if used as a stopper when spraying (resin).
すなわち、本発明は、フレキシブル基板と、一部にフレキシブル領域を露出する形で当該フレキシブル基板のリジッド領域に積層されたリジッド基板とを備えたリジッド・フレックス多層プリント配線板であって、当該リジッド基板は、フレキシブル基板上に、第一絶縁樹脂層と、当該第一絶縁樹脂層に積層された厚さが１００μｍ以上のコア基材からなる厚み調節層と、当該厚み調節層に積層された第二絶縁樹脂層と配線層との任意の層数の積層体からなるビルドアップ層と、当該ビルドアップ層における最外層の配線パターンを保護するソルダーレジストを有すると共に、当該フレキシブル基板上のリジッド領域とフレキシブル領域の境界部に、フレキシブル領域側へ突出し、厚み調節層とビルドアップ層のリジッド領域とフレキシブル領域の境界部に位置する側面壁に塗布する被覆用樹脂を外側面にとどめて被覆用樹脂のストッパーとして機能する第一絶縁樹脂層の一部からなる突出部を有し、且つ、当該厚み調節層とビルドアップ層のリジッド領域とフレキシブル領域の境界部に位置する側面壁と第一絶縁樹脂層の一部からなる突出部の外側面が、被覆用樹脂によって被覆されており、当該被覆用樹脂は第一絶縁樹脂層の一部からなる突出部の外側面にとどまっていることを特徴とするリジッド・フレックス多層プリント配線板により、上記課題を解決したものである。
また、本発明は、フレキシブル基板と、一部にフレキシブル領域を露出する形で当該フレキシブル基板のリジッド領域に積層されたリジッド基板とを備えたリジッド・フレックス多層プリント配線板の製造方法であって、フレキシブル基板の少なくとも一方の面に、当該フレキシブル基板のフレキシブル領域となる部分に対応する開口部が形成された第一絶縁樹脂層と、当該第一絶縁樹脂層の開口部に対応するダミーパターンを備えた厚さが１００μｍ以上のコア基材からなる厚み調節層と、任意の数の第二絶縁樹脂層と配線パターンとからなるビルドアップ層とをこの順に積層する工程と、当該ビルドアップ層の外側面からルータ加工を行ない、当該厚み調節層のダミーパターンの外周に沿うようにスリットを形成することによって、フレキシブル領域側へ突出する第一絶縁樹脂層の一部からなる突出部を形成すると共に、フレキシブル基板のフレキシブル領域上の不要部を除去する工程と、当該不要部の除去により露出した厚み調節層とビルドアップ層のリジッド領域とフレキシブル領域の境界部に位置する側面壁に被覆用樹脂を塗布する工程とを有することを特徴とするリジッド・フレックス多層プリント配線板の製造方法により、上記課題を解決したものである。
That is, the present invention provides a rigid-flex multilayer printed wiring board comprising a flexible substrate and a rigid substrate laminated on a rigid region of the flexible substrate with the flexible region partially exposed. is a flexible substrate, a first insulating resin layer, a thickness adjustment layer made of a core base material with a thickness of 100 μm or more laminated on the first insulating resin layer, and a second thickness adjustment layer laminated on the thickness adjustment layer. It has a buildup layer consisting of a laminated body of an arbitrary number of layers of an insulating resin layer and a wiring layer, and a solder resist that protects the outermost layer wiring pattern in the buildup layer, and a rigid area on the flexible substrate and a flexible At the boundary of the area, the coating resin is applied to the side wall that protrudes toward the flexible area and is located at the boundary between the rigid area and the flexible area of the thickness adjustment layer and the buildup layer. A side wall and the first insulating resin layer that have a protrusion formed from a part of the first insulating resin layer that functions as a stopper and are located at the boundary between the rigid region and the flexible region of the thickness adjustment layer and the buildup layer. The outer surface of the protrusion made of a part of the first insulating resin layer is covered with a coating resin, and the coating resin remains on the outer surface of the protrusion made of a part of the first insulating resin layer. The above problem has been solved by using a rigid-flex multilayer printed wiring board.
The present invention also provides a method for manufacturing a rigid-flex multilayer printed wiring board comprising a flexible substrate and a rigid substrate laminated on a rigid region of the flexible substrate with the flexible region partially exposed. A first insulating resin layer in which an opening corresponding to a portion of the flexible substrate that becomes a flexible region is formed on at least one surface of the flexible substrate, and a dummy pattern corresponding to the opening in the first insulating resin layer. A step of laminating in this order a thickness adjustment layer made of a core base material having a thickness of 100 μm or more and a buildup layer made of an arbitrary number of second insulating resin layers and a wiring pattern, and By performing router processing from the side surface and forming a slit along the outer periphery of the dummy pattern of the thickness adjustment layer, a protrusion made of a part of the first insulating resin layer protruding toward the flexible region is formed, and The process of removing unnecessary parts on the flexible area of the flexible substrate, and applying coating resin to the side walls located at the boundary between the rigid area and the flexible area of the thickness adjustment layer and buildup layer exposed by the removal of the unnecessary area. The above-mentioned problem has been solved by a method for manufacturing a rigid-flex multilayer printed wiring board, which comprises the steps of:
本発明によれば、フレキシブル基板上のフレキシブル領域側へ突出する第一絶縁樹脂層の一部からなる突出部を被覆用樹脂のストッパーとして機能させることができるので、樹脂の粉落ち（ゴミ）を防止するために、厚み調節層とビルドアップ層のリジッド領域とフレキシブル領域の境界部に位置する側面壁に被覆用樹脂を塗布しても、当該樹脂がフレキシブル基板のフレキシブル領域に流れ込む量を抑えることができる。もって、フレキシブル基板のフレキシブル領域の屈曲性を維持しながら、フレキシブル基板のリジッド領域に積層されるリジッド基板のリジッド領域とフレキシブル領域の境界部に位置するルータ加工面からの樹脂の粉落ち（ゴミ）の発生がないリジッド・フレックス多層プリント配線板を得ることができる。 According to the present invention, since the protrusion formed by a part of the first insulating resin layer protruding toward the flexible area on the flexible substrate can function as a stopper for the coating resin, resin powder (dust) can be prevented from falling off. In order to prevent this, even if a coating resin is applied to the side wall located at the boundary between the rigid region and the flexible region of the thickness adjustment layer and the buildup layer, the amount of the resin flowing into the flexible region of the flexible substrate can be suppressed. Can be done. As a result, while maintaining the flexibility of the flexible area of the flexible substrate, resin powder (dust) falls off from the router processing surface located at the boundary between the rigid area and the flexible area of the rigid substrate that is laminated on the rigid area of the flexible substrate. It is possible to obtain a rigid-flex multilayer printed wiring board that does not cause the occurrence of.
以下、本発明リジッド・フレックス多層プリント配線板の実施の形態を、図１を用いて説明する。 Hereinafter, an embodiment of the rigid-flex multilayer printed wiring board of the present invention will be described using FIG. 1.
図１において、ＰＷはリジッド・フレックス多層プリント配線板で、当該リジッド・フレックス多層プリント配線板ＰＷは、中心部に配置されたフレキシブル基板６と、一部に屈曲可能なフレキシブル領域Ｆを露出する形で、当該フレキシブル基板６の表裏面に積層されたリジッド基板１６とから構成されている。当該フレキシブル基板６とリジッド基板１６が重なる部分は、部品実装が可能な「リジッド領域Ｒ」である。
具体的に説明すると、フレキシブル基板６は、フレキシブルベース基板１と、当該フレキシブルベース基板１の表裏面に形成された第一配線パターン２と、当該第一配線パターン２を保護する接着剤３とカバーフィルム４とからなるカバーレイ５で構成されている。
一方、リジッド基板１６は、フレキシブル基板６上に配置された第一絶縁樹脂層７と、当該第一絶縁樹脂層７に積層された厚さが１００μｍ以上のコア基材からなる厚み調節層８と、当該厚み調節層８上に交互に４層ずつ積層された第二絶縁樹脂層９と第二配線層（第二配線パターン１０が形成される配線層）からなるビルドアップ層１５とから構成されている。
当該フレキシブル基板６に積層された第一絶縁樹脂層７の一部はフレキシブル領域Ｆ側に突出し、フレキシブル基板６上のリジッド領域Ｒとフレキシブル領域Ｆの境界部には、第一絶縁樹脂層７の一部からなる突出部７ｃが対向形設されている。
また、当該厚み調節層８とビルドアップ層１５のリジッド領域Ｒとフレキシブル領域Ｆの境界部に位置する側面壁１７から、第一絶縁樹脂層７の一部からなる突出部７ｃの外側面（外層側の面）にかけては、被覆用樹脂１８によって被覆されている。
In FIG. 1, PW is a rigid-flex multilayer printed wiring board, and the rigid-flex multilayer printed wiring board PW has a flexible substrate 6 disposed in the center and a flexible region F that is partially exposed. The rigid substrate 16 is laminated on the front and back surfaces of the flexible substrate 6. The portion where the flexible board 6 and the rigid board 16 overlap is a "rigid region R" in which components can be mounted.
Specifically, the flexible substrate 6 includes a flexible base substrate 1, a first wiring pattern 2 formed on the front and back surfaces of the flexible base substrate 1, an adhesive 3 for protecting the first wiring pattern 2, and a cover. The coverlay 5 includes a film 4 and a coverlay 5.
On the other hand, the rigid substrate 16 includes a first insulating resin layer 7 disposed on the flexible substrate 6, and a thickness adjustment layer 8 made of a core base material having a thickness of 100 μm or more and laminated on the first insulating resin layer 7. , a build-up layer 15 consisting of a second insulating resin layer 9 and a second wiring layer (the wiring layer on which the second wiring pattern 10 is formed), which are alternately laminated in four layers on the thickness adjustment layer 8. ing.
A part of the first insulating resin layer 7 laminated on the flexible substrate 6 protrudes toward the flexible region F, and a portion of the first insulating resin layer 7 is located at the boundary between the rigid region R and the flexible region F on the flexible substrate 6. A protruding portion 7c consisting of a portion is formed opposite to each other.
Further, from the side wall 17 located at the boundary between the rigid region R and the flexible region F of the thickness adjustment layer 8 and the buildup layer 15, The side surface) is covered with a coating resin 18.
そして、当該リジッド領域Ｒには、フレキシブル基板６を挟んだ両面に形成されている内層の第二配線パターン１０と当該内層の第二配線パターン１０の形成層間に位置する第一配線パターン２とを接続するベリードホール１１と、上下方向に隣接する第二配線パターン１０間を接続するブラインドビアホール１２と、フレキシブル基板６を挟んだ両面に積層されている外層の第二配線パターン１０と当該外層の第二配線パターン１０の形成層間に位置する配線パターン（ここでは「第一配線パターン２」「内層の第二配線パターン１０」に相当）とを接続する貫通めっきスルーホール１３と、ビルドアップ層１５における最外層の第二配線パターン１０を保護するソルダーレジスト１４が形成されている。 In the rigid region R, a second wiring pattern 10 of the inner layer formed on both sides of the flexible substrate 6 and a first wiring pattern 2 located between the layers forming the second wiring pattern 10 of the inner layer are formed. A buried hole 11 for connection, a blind via hole 12 for connecting vertically adjacent second wiring patterns 10, and a second wiring pattern 10 for the outer layer laminated on both sides of the flexible substrate 6 and the second wiring pattern 10 for the outer layer. A through-plated through hole 13 that connects the wiring pattern located between the formation layers of the second wiring pattern 10 (corresponding to the "first wiring pattern 2" and "inner layer second wiring pattern 10" here) and the buildup layer 15 A solder resist 14 is formed to protect the second wiring pattern 10 in the outermost layer.
この実施の形態では、図１に示したように、フレキシブル基板６上に、第一絶縁樹脂層７を介して、厚さが１００μｍ以上のコア基材からなる厚み調節層８を有している。厚さが１００μｍ以上のコア基材からなる厚み調節層８は、非常に剛性が高い（即ち、ガラスクロスが太い）ため、これによって高密度配線化を確保しつつ、高い剛性を付与することができる。
また、フレキシブル基板６上のリジッド領域Ｒとフレキシブル領域Ｆの境界部に、フレキシブル領域Ｆ側へ突出する第一絶縁樹脂層７の一部からなる突出部７ｃを有し、厚み調節層８とビルドアップ層１５のリジッド領域Ｒとフレキシブル領域Ｆの境界部に位置する側面壁１７と、当該第一絶縁樹脂層７の一部からなる突出部７ｃの外側面が被覆用樹脂１８によって被覆されているため、側面壁１７からの樹脂の粉落ち（ゴミ）の発生が少なくなっている。一方、被覆用樹脂１８は、突出部７ｃの外側面にとどまり、フレキシブル基板６のフレキシブル領域Ｆに流れ込みにくくなるため、フレキシブル領域Ｆの屈曲性は維持される。
なお、第一絶縁樹脂層７の一部からなる突出部７ｃの形状は特に制限されないが、本実施の形態においては板状である。当該突出部７ｃの寸法は、例えば、リジッド領域Ｒとフレキシブル領域Ｆの境界部からフレキシブル領域Ｆ側へ５０μｍ～１０００μｍの範囲内である。また、厚みは、３０μｍ～１５０μｍの範囲内である。
In this embodiment, as shown in FIG. 1, a thickness adjustment layer 8 made of a core base material with a thickness of 100 μm or more is provided on a flexible substrate 6 via a first insulating resin layer 7. . The thickness adjustment layer 8 made of a core base material with a thickness of 100 μm or more has very high rigidity (that is, the glass cloth is thick), so it is possible to provide high rigidity while ensuring high density wiring. can.
Further, at the boundary between the rigid region R and the flexible region F on the flexible substrate 6, there is a protrusion 7c made of a part of the first insulating resin layer 7 that protrudes toward the flexible region F side, and the thickness adjustment layer 8 and the build The side wall 17 located at the boundary between the rigid region R and the flexible region F of the up layer 15 and the outer surface of the protrusion 7c made of a part of the first insulating resin layer 7 are covered with a coating resin 18. Therefore, the occurrence of resin powder falling (dust) from the side wall 17 is reduced. On the other hand, the coating resin 18 remains on the outer surface of the protrusion 7c and is difficult to flow into the flexible region F of the flexible substrate 6, so that the flexibility of the flexible region F is maintained.
Note that the shape of the protruding portion 7c that is a part of the first insulating resin layer 7 is not particularly limited, but in this embodiment, it is plate-shaped. The dimensions of the protrusion 7c are, for example, within the range of 50 μm to 1000 μm from the boundary between the rigid region R and the flexible region F to the flexible region F side. Further, the thickness is within the range of 30 μm to 150 μm.
続いて、本発明リジッド・フレックス多層プリント配線板ＰＷの製造方法を、図２～図７を用いて説明する。尚、文中に出てくる「絶縁接着剤層」は、実際には、加熱・積層プレスで硬化された後は、半硬化状態の接着剤ではなく、硬化済みの「絶縁樹脂層」となるものであるが、説明の便宜上、硬化前後に関係なく「絶縁接着剤層」という表現で説明を進めていく。また、図中、従来技術と同じ部位には、同じ符号を付すようにした。 Next, a method for manufacturing the rigid-flex multilayer printed wiring board PW of the present invention will be explained using FIGS. 2 to 7. In addition, the "insulating adhesive layer" that appears in the text actually becomes a hardened "insulating resin layer" after being cured by heating and laminating press, rather than a semi-hardened adhesive. However, for convenience of explanation, the expression "insulating adhesive layer" will be used regardless of whether it is before or after curing. Further, in the drawings, the same parts as in the prior art are given the same reference numerals.
まず、厚さが２５～１００μｍ程度からなるフレキシブルベース基板１の両面に、厚さが９～３５μｍの金属箔（例えば「銅箔」）をエッチング処理することによって、第一配線パターン２を形成し、次いで、当該第一配線パターン２を保護するカバーレイ５｛例えば、接着剤３とポリイミドフィルム等のカバーフィルム４からなる厚さが２５～７０μｍ程度のカバーレイ｝を積層することによって、図２（ａ）に示したフレキシブル基板６を得る。 First, a first wiring pattern 2 is formed by etching metal foil (for example, "copper foil") with a thickness of 9 to 35 μm on both sides of a flexible base substrate 1 with a thickness of about 25 to 100 μm. Then, by laminating a coverlay 5 {for example, a coverlay with a thickness of about 25 to 70 μm consisting of an adhesive 3 and a cover film 4 such as a polyimide film} that protects the first wiring pattern 2, the structure shown in FIG. The flexible substrate 6 shown in (a) is obtained.
次に、１００μｍ以上の厚みを有するコア基材８ａ(例えば、ガラスクロスなどの補強繊維基材にエポキシ樹脂などの熱硬化性樹脂を含浸させた絶縁基板)の両面に、厚さが３５～１０５μｍからなる導体層１９ａ（例えば「銅箔」）が積層された両面金属箔張り積層板を用意し（図２（ｂ１）参照）、当該両面金属箔張り積層板をエッチング処理することによって、後にフレキシブル基板６のフレキシブル領域Ｆとなる部分に対応したベタ状のダミーパターン１９を有する厚み調節層８を得る（図２（ｂ２）参照）。 Next, a core base material 8a having a thickness of 100 μm or more (for example, an insulating substrate made of a reinforcing fiber base material such as glass cloth impregnated with a thermosetting resin such as an epoxy resin) is coated with a thickness of 35 to 105 μm on both sides. A double-sided metal foil-clad laminate on which a conductor layer 19a (for example, "copper foil") is laminated is prepared (see FIG. 2 (b1)), and by etching the double-sided metal foil-clad laminate, a flexible A thickness adjustment layer 8 having a solid dummy pattern 19 corresponding to a portion of the substrate 6 that will become the flexible region F is obtained (see FIG. 2(b2)).
次に、フレキシブル基板６とダミーパターン１９が形成された厚み調節層８とを接着する第一絶縁接着剤層７ａを用意し（図２（ｃ１）参照）、当該ダミーパターン１９に対応する箇所に、これよりも若干大きめの開口部７ｂを、ルータ加工やパンチングプレス加工などによって形成する（図２（ｃ２）参照）。 Next, a first insulating adhesive layer 7a is prepared for bonding the flexible substrate 6 and the thickness adjustment layer 8 on which the dummy pattern 19 is formed (see FIG. 2(c1)), and , an opening 7b slightly larger than this is formed by router machining, punching press machining, etc. (see FIG. 2(c2)).
次に、図２(ｄ)に示したように、フレキシブル基板６の表裏面に、開口部７ｂが形成された第一絶縁接着剤層７ａ、ダミーパターン１９が形成された厚み調節層８、第二絶縁接着剤層９ａ(例えば、ガラスクロスなどの補強繊維基材にエポキシ樹脂などの熱硬化性樹脂を含浸させた、厚さが２０～６０μｍからなる半硬化状態のプリプレグなど)、金属箔２０(例えば、厚さが９～１８μｍの銅箔)をこの順に配置した後、加熱・積層プレスを行うことによって、上記構成部材を一体化形成する（図３（ｅ）参照）。 Next, as shown in FIG. 2(d), on the front and back surfaces of the flexible substrate 6, a first insulating adhesive layer 7a in which an opening 7b is formed, a thickness adjustment layer 8 in which a dummy pattern 19 is formed, and a third two insulating adhesive layers 9a (for example, a semi-cured prepreg with a thickness of 20 to 60 μm, made by impregnating a reinforcing fiber base material such as glass cloth with a thermosetting resin such as epoxy resin), metal foil 20; (For example, copper foil having a thickness of 9 to 18 μm) are arranged in this order, and then the above-mentioned constituent members are integrally formed by heating and laminating pressing (see FIG. 3(e)).
ここで、本実施の形態では、厚み調節層８にはダミーパターン１９のみを形成する例を示したが、ダミーパターン１９の形成面とは反対側の面にも、勿論、配線パターンを形成することは可能である。この場合、コア基材８ａに積層される導体層１９ａの厚みが３５μｍ程度であれば、そのままエッチング処理して形成すればよく、７０～１０５μｍと厚い場合には、一度、ダウンエッチングで導体層１９ａを薄くしてから、エッチング処理で形成すればよい。 Here, in this embodiment, an example is shown in which only the dummy pattern 19 is formed on the thickness adjustment layer 8, but of course a wiring pattern may also be formed on the surface opposite to the surface on which the dummy pattern 19 is formed. It is possible. In this case, if the thickness of the conductor layer 19a laminated on the core base material 8a is about 35 μm, it is sufficient to form the conductor layer 19a by etching as is. It can be formed by etching after making it thin.
次に、図３（ｆ）に示したように、ドリル加工で貫通孔１１ａ（例えば、孔径が１５０～３００μｍの貫通孔）を穿孔した後、過マンガン酸ナトリウム溶液や過マンガン酸カリウム溶液等の湿式デスミア処理、あるいはプラズマ等の乾式デスミア処理で当該貫通孔１１ａの内壁をクリーニングし、次いで、無電解めっき処理及び電解めっき処理を順次行うことによって、当該貫通孔１１ａを含む基板全面にめっき膜１１ｂ（例えば、設定膜厚を２０μｍとした「銅めっき膜」）を析出させる（図３（ｇ）参照）。 Next, as shown in FIG. 3(f), after drilling a through hole 11a (for example, a through hole with a hole diameter of 150 to 300 μm), a solution of sodium permanganate, potassium permanganate, etc. The inner wall of the through hole 11a is cleaned by a wet desmear process or a dry desmear process such as plasma, and then an electroless plating process and an electrolytic plating process are sequentially performed to form a plating film 11b on the entire surface of the substrate including the through hole 11a. (For example, a "copper plating film" with a set film thickness of 20 μm) is deposited (see FIG. 3(g)).
次に、図４（ｈ）に示したように、めっき膜１１ｂが析出された貫通孔１１ａに孔埋め樹脂１１ｃを充填した後、周知のフォトエッチングプロセス｛導体層（ここでは、金属箔２０とめっき膜１１ｂを足した導体層に相当）上に感光性のエッチングレジストをラミネートした後、露光、現像処理（例えば、１％程度の炭酸ナトリウム溶液による現像処理）を行ってエッチングレジストパターンを形成し、次いで、当該エッチングレジストパターンから露出した導体層をエッチング処理（例えば、塩化第二鉄溶液や塩化第二銅溶液によるエッチング処理）によって除去した後、不要となったエッチングレジストパターンを剥離（例えば、３％程度の水酸化ナトリウム溶液による剥離）する工程｝を行なうことによって、第二配線パターン１０を形成するとともに、両面に形成された第二配線パターン１０と当該第二配線パターン１０の形成層間に位置する第一配線パターン２とを接続するベリードホール１１を形成する（図４（ｉ）参照）。 Next, as shown in FIG. 4H, the through hole 11a in which the plating film 11b has been deposited is filled with hole-filling resin 11c, and then a well-known photoetching process {conductor layer (here, metal foil 20 and After laminating a photosensitive etching resist on the conductor layer (corresponding to the conductor layer including the plating film 11b), an etching resist pattern is formed by exposing and developing (e.g., developing with a 1% sodium carbonate solution). Next, after removing the conductor layer exposed from the etching resist pattern by etching treatment (for example, etching treatment using a ferric chloride solution or cupric chloride solution), the unnecessary etching resist pattern is peeled off (for example, The second wiring pattern 10 is formed by performing the peeling process (with an approximately 3% sodium hydroxide solution), and the second wiring pattern 10 is formed on both sides of the second wiring pattern 10. A buried hole 11 is formed to connect the located first wiring pattern 2 (see FIG. 4(i)).
次に、図４（ｊ）に示したように、第二配線パターン１０が形成された第二絶縁接着剤層９ａの上に、更に第二絶縁接着剤層９ａと金属箔２０を順次積層した後、コンフォーマル工法やラージウィンドウ工法、及びカッパーダイレクト工法などのレーザ加工を行うことによって、下層の第二配線パターン１０を露出させる非貫通穴１２ａ（例えば、トップ径が１００～２００μｍ、ボトム径が８０～１８０μｍの非貫通穴）を形成し（図５（ｋ）参照）、次いで、デスミア処理により当該非貫通穴１２ａ内をクリーニングした後、無電解めっき処理及び電解めっき処理（フィルドビア用のめっき液を用いた電解めっき処理）を順次行うことによって、当該非貫通穴１２ａにめっき１２ｂ（例えば、銅めっき）を充填する（図５（ｌ）参照）。 Next, as shown in FIG. 4(j), a second insulating adhesive layer 9a and a metal foil 20 were further laminated in sequence on the second insulating adhesive layer 9a on which the second wiring pattern 10 was formed. After that, a non-through hole 12a (for example, a top diameter of 100 to 200 μm and a bottom diameter of 100 to 200 μm and a bottom diameter of A non-through hole 12a of 80 to 180 μm is formed (see FIG. 5(k)), and then the inside of the non-through hole 12a is cleaned by desmear treatment, followed by electroless plating treatment and electrolytic plating treatment (plating solution for filled vias). The non-through hole 12a is filled with the plating 12b (for example, copper plating) by sequentially performing an electrolytic plating process using a plating method (see FIG. 5(l)).
次に、図５（ｌ）に示した基板の導体層（金属箔２０とこの上に析出されためっき１２ｂの一部からなるめっき膜）に対してフォトエッチングプロセスを行ことによって、上層の第二配線パターン１０を形成するとともに当該上層の第二配線パターン１０と下層の第二配線パターン１０間を接続するブラインドビアホール１２を形成する（図５（ｍ）参照）。 Next, a photo-etching process is performed on the conductor layer (plated film consisting of the metal foil 20 and a part of the plating 12b deposited on the metal foil 20) of the substrate shown in FIG. 5(l). A second wiring pattern 10 is formed, and a blind via hole 12 is formed to connect the second wiring pattern 10 in the upper layer and the second wiring pattern 10 in the lower layer (see FIG. 5(m)).
次に、図４（ｊ）～図５（ｍ）と同じ工程を１回行った後、図４（ｊ）～図５（ｌ）と同じ工程を行なうことによって、図６（ｎ）に示した状態の基板を形成し、次いで、ベリードホール１１の形成と同じ要領で、貫通孔１３ａ（例えば、孔径が２００～８００μｍの貫通孔）及びめっき膜１３ｂ（例えば、設定膜厚を２０μｍとしためっき膜）を形成する（図６（ｏ）参照）。 Next, by performing the same steps as in FIGS. 4(j) to 5(m) once, and then performing the same steps as in FIGS. 4(j) to 5(l), the image shown in FIG. 6(n) is obtained. Next, in the same manner as the buried hole 11 was formed, a through hole 13a (for example, a through hole with a hole diameter of 200 to 800 μm) and a plating film 13b (for example, a set film thickness of 20 μm) were formed. (see FIG. 6(o)).
次に、フォトエッチングプロセスを行なうことによって、外層の第二配線パターン１０を形成するとともに、両面に形成された外層の第二配線パターン１０と当該外層の第二配線パターン１０の形成層間に位置する第一配線パターン２と内層の第二配線パターン１０を接続する貫通めっきスルーホール１３を形成し、次いで、当該外層の第二配線パターン１０を保護するソルダーレジスト１４を形成することによって、図６（ｐ）に示したように、厚み調節層８上にビルドアップ層１５が積層された中間基板ＭＰＷを得る。 Next, by performing a photo-etching process, the second wiring pattern 10 of the outer layer is formed, and the second wiring pattern 10 of the outer layer formed on both sides is located between the formation layer of the second wiring pattern 10 of the outer layer. By forming a through-plating through hole 13 connecting the first wiring pattern 2 and the second wiring pattern 10 in the inner layer, and then forming a solder resist 14 to protect the second wiring pattern 10 in the outer layer, As shown in p), an intermediate substrate MPW in which a buildup layer 15 is laminated on a thickness adjustment layer 8 is obtained.
次に、図６（ｐ)に示した中間基板ＭＰＷのビルドアップ層１５の外側面Ａに対してルータ加工を行ない、ダミーパターン１９の外周に沿うようにスリット２２を形成することによって、フレキシブル領域Ｆ側へ突出する第一絶縁樹脂層７（第一絶縁接着剤層７ａ）の一部からなる突出部７ｃを形成する（図７（ｑ）参照）と共に、フレキシブル基板６のフレキシブル領域Ｆ上の不要部２１ａを除去する（図７（ｒ）参照）。
当該突出部７ｃの寸法は、例えば、リジッド領域Ｒとフレキシブル領域Ｆの境界部からフレキシブル領域Ｆ側へ５０μｍ～１０００μｍの範囲内とすることが、被覆用樹脂がフレキシブル領域Ｆ側に流れ込む量を抑える上で望ましい。
同様の手段で、中間基板ＭＰＷの他方の面Ｂ側の不要部２１ｂを除去する。
Next, router processing is performed on the outer surface A of the buildup layer 15 of the intermediate substrate MPW shown in FIG. A protruding portion 7c consisting of a part of the first insulating resin layer 7 (first insulating adhesive layer 7a) protruding toward the F side is formed (see FIG. 7(q)), and a protruding portion 7c is formed on the flexible region F of the flexible substrate 6. The unnecessary portion 21a is removed (see FIG. 7(r)).
The dimensions of the protrusion 7c are, for example, within the range of 50 μm to 1000 μm from the boundary between the rigid region R and the flexible region F toward the flexible region F to suppress the amount of coating resin flowing into the flexible region F. preferred above.
The unnecessary portion 21b on the other surface B side of the intermediate substrate MPW is removed by the same means.
次いで、ルータ加工やパンチング加工により外形加工を行なった後、図７（ｓ）に示したように、リジッド基板１６の厚み調節層８とビルドアップ層１５のリジッド領域Ｒとフレキシブル領域Ｆの境界部に位置する側面壁（ルータ加工面）１７に、ディスペンサ等の手段で被覆用樹脂１８を塗布して、リジッド・フレックス多層プリント配線板ＰＷを得る。
ここで、当該被覆用樹脂１８としては、特に限定はしないが、ルータ加工面に塗布した樹脂が、フレキシブル領域Ｆ上に拡散するのを少なくするために、ＵＶ硬化タイプや溶剤揮発タイプ等の速硬化性の樹脂を用いるのが望ましい。
また、ルータ加工面には、クラックが入る場合があり、ここから水分が入り込んでショート不良が発生する懸念もあるため、上記速硬化性に加えて絶縁性や防湿性も兼ね備えた樹脂を用いるのがより望ましい。
勿論、熱硬化性タイプの樹脂を用いることも可能である。
Next, after performing external shape processing by router processing or punching processing, as shown in FIG. A coating resin 18 is applied to the side wall (router processed surface) 17 located at , using a dispenser or the like, to obtain a rigid-flex multilayer printed wiring board PW.
Here, the coating resin 18 is not particularly limited, but in order to reduce the diffusion of the resin applied to the router processing surface onto the flexible area F, a UV curing type, a solvent evaporation type, etc. It is desirable to use a curable resin.
In addition, cracks may form on the machined surface of the router, and there is a risk that moisture may enter through these cracks, causing short-circuits. Therefore, in addition to the quick-curing properties mentioned above, it is recommended to use a resin that also has insulating and moisture-proof properties. is more desirable.
Of course, it is also possible to use a thermosetting type resin.
本発明の注目すべき点は、厚み調節層８とビルドアップ層１５のリジッド領域Ｒとフレキシブル領域Ｆの境界部に位置する側面壁（ルータ加工面）１７に被覆用樹脂１８を塗布する際、フレキシブル領域Ｆ側へ突出する第一絶縁樹脂層７（第一絶縁接着剤層７ａ）の一部からなる突出部７ｃを当該樹脂のストッパーとして機能させる点にある。当該突出部７ｃの存在により、側面壁１７にディスペンサ等の手段で被覆用樹脂１８を塗布しても、当該樹脂がフレキシブル領域Ｆ側に流れ込む量を抑えることができる。
これによって、フレキシブル基板のフレキシブル領域の屈曲性を維持しつつ、フレキシブル基板のリジッド領域に積層されるリジッド基板のリジッド領域とフレキシブル領域の境界部に位置する側面壁（ルータ加工面）を樹脂で被覆できるため、ルータ加工に起因する当該側面壁からの樹脂の粉落ち（ゴミ）の発生がないリジッド・フレックス多層プリント配線板が得られる。
なお、突出部７ｃが被覆用樹脂のストッパーとして機能する理由は、不要部を除去するルータ加工の際、ルータビットの先端が突出部７ｃの上面に接触し、当該面が適度に荒れた状態となるため、塗布した被覆用樹脂が、突出部７ｃの上面に留まり易くなっているためと考えられる。
The noteworthy point of the present invention is that when coating the coating resin 18 on the side wall (router processed surface) 17 located at the boundary between the rigid region R and the flexible region F of the thickness adjustment layer 8 and the buildup layer 15, The point is that a protruding portion 7c formed of a part of the first insulating resin layer 7 (first insulating adhesive layer 7a) protruding toward the flexible region F side functions as a stopper for the resin. Due to the presence of the protrusion 7c, even when the coating resin 18 is applied to the side wall 17 using a dispenser or the like, the amount of the resin flowing into the flexible region F side can be suppressed.
As a result, while maintaining the flexibility of the flexible area of the flexible substrate, the side wall (router processed surface) located at the boundary between the rigid area and the flexible area of the rigid substrate that is laminated on the rigid area of the flexible substrate is coated with resin. As a result, a rigid-flex multilayer printed wiring board can be obtained in which resin powder (dust) does not fall off from the side wall due to router processing.
The reason why the protruding part 7c functions as a stopper for the coating resin is that during router processing to remove unnecessary parts, the tip of the router bit comes into contact with the upper surface of the protruding part 7c, and the surface becomes moderately rough. This is considered to be because the applied coating resin tends to stay on the upper surface of the protrusion 7c.
本発明を説明するに当たって、厚み調節層８とビルドアップ層１５のリジッド領域Ｒとフレキシブル領域Ｆの境界部に位置する側面壁（ルータ加工面）１７が、フレキシブル基板６に対して垂直になるように加工される例を説明してきたが、図８に示すように、外層側から内層側に向かうにつれて、リジッド領域Ｒ側に傾斜するようにルータ加工することも可能である。この場合、より、被覆用樹脂１８がフレキシブル領域Ｆ側に流れ込む量を抑えることができる。
なお、当該側面壁（ルータ加工面）１７の傾斜は、不要部２１を除去するルータ加工の回転数を上げることで、容易に加工することができる。
In explaining the present invention, the side wall (router processing surface) 17 located at the boundary between the rigid region R and the flexible region F of the thickness adjustment layer 8 and the buildup layer 15 will be perpendicular to the flexible substrate 6. As shown in FIG. 8, it is also possible to perform router processing so as to be inclined toward the rigid region R side from the outer layer side toward the inner layer side. In this case, the amount of the coating resin 18 flowing into the flexible region F side can be further suppressed.
Note that the slope of the side wall (router processed surface) 17 can be easily processed by increasing the rotation speed of the router processing for removing the unnecessary portion 21.
また、本発明を説明するに当たって、フレキシブル基板６の表裏の両面に、交互に４層ずつ形成された第二絶縁樹脂層９及び第二配線パターン１０からなるビルドアップ層１５を積層した両面構造のものを用いて説明したが、本発明を逸脱しない範囲であれば、他の構成にも本発明を適用することは可能であり、さらにまた、板厚、層数、材料なども本発明の範囲内で変更が可能である。 Further, in explaining the present invention, a double-sided structure in which build-up layers 15 consisting of a second insulating resin layer 9 and a second wiring pattern 10, which are alternately formed in four layers, are laminated on both the front and back sides of the flexible substrate 6 will be described. Although the present invention has been explained using a material, it is possible to apply the present invention to other configurations as long as it does not depart from the scope of the present invention.Furthermore, plate thickness, number of layers, materials, etc. are also within the scope of the present invention. Changes can be made within.
１：フレキシブルベース基板
２：第一配線パターン
３：接着剤
４：カバーフィルム
５：カバーレイ
６：フレキシブル基板
７：第一絶縁樹脂層
７ａ：第一絶縁接着剤層
７ｂ：開口部
７ｃ：突出部
８：厚み調節層
８ａ：コア基材
８ｂ：側面壁
９：第二絶縁樹脂層
９ａ：第二絶縁接着剤層
１０：第二配線パターン
１１：ベリードホール
１１ａ：貫通孔
１１ｂ：めっき膜
１１ｃ：孔埋め樹脂
１２：ブラインドビアホール
１２ａ：非貫通穴
１２ｂ：めっき
１３：貫通めっきスルーホール
１３ａ：貫通孔
１３ｂ：めっき膜
１４：ソルダーレジスト
１５：ビルドアップ層
１６：リジッド基板
１７：厚み調節層８とビルドアップ層１５のリジッド領域Ｒとフレキシブル領域Ｆの境界部に位置する側面壁（ルータ加工面）
１８：被覆用樹脂
１９：ダミーパターン
１９ａ：導体層
２０：金属箔
２１、２１ａ、２１ｂ：不要部
２２：スリット
２３：絶縁樹脂層
２４：配線パターン
２５：レーザ受けパターン
Ｆ：フレキシブル領域
Ｒ：リジッド領域
ＭＰＷ：中間基板
ＰＷ：リジッド・フレックス多層プリント配線板
1: Flexible base substrate 2: First wiring pattern 3: Adhesive 4: Cover film 5: Cover lay 6: Flexible substrate 7: First insulating resin layer 7a: First insulating adhesive layer 7b: Opening 7c: Protrusion 8: Thickness adjustment layer 8a: Core base material 8b: Side wall 9: Second insulating resin layer 9a: Second insulating adhesive layer 10: Second wiring pattern 11: Buried hole 11a: Through hole 11b: Plating film 11c: Hole-filling resin 12: Blind via hole 12a: Non-through hole 12b: Plating 13: Through-plating through hole 13a: Through hole 13b: Plating film 14: Solder resist 15: Build-up layer 16: Rigid substrate 17: Thickness adjustment layer 8 and build Side wall located at the boundary between the rigid region R and the flexible region F of the up layer 15 (router processing surface)
18: Coating resin 19: Dummy pattern 19a: Conductor layer 20: Metal foil 21, 21a, 21b: Unnecessary portion 22: Slit 23: Insulating resin layer 24: Wiring pattern 25: Laser receiving pattern F: Flexible region R: Rigid region MPW: Intermediate board PW: Rigid-flex multilayer printed wiring board
Claims (6)
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|---|---|---|---|---|
| JP2007266195A (en) | 2006-03-28 | 2007-10-11 | Dainippon Printing Co Ltd | Multilayer printed-wiring board and manufacturing method therefor |
| JP2009038363A (en) | 2007-07-09 | 2009-02-19 | Panasonic Corp | Rigid flexible printed circuit board, and its manufacturing method |
| JP2014093527A (en) | 2012-11-02 | 2014-05-19 | Samsung Electro-Mechanics Co Ltd | Printed circuit board manufacturing method |
| JP2016192475A (en) | 2015-03-31 | 2016-11-10 | 太陽誘電株式会社 | Component built-in substrate and semiconductor module |
| JP2019047063A (en) | 2017-09-06 | 2019-03-22 | イビデン株式会社 | Printed circuit board and manufacturing method thereof |
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2019
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007266195A (en) | 2006-03-28 | 2007-10-11 | Dainippon Printing Co Ltd | Multilayer printed-wiring board and manufacturing method therefor |
| JP2009038363A (en) | 2007-07-09 | 2009-02-19 | Panasonic Corp | Rigid flexible printed circuit board, and its manufacturing method |
| JP2014093527A (en) | 2012-11-02 | 2014-05-19 | Samsung Electro-Mechanics Co Ltd | Printed circuit board manufacturing method |
| JP2016192475A (en) | 2015-03-31 | 2016-11-10 | 太陽誘電株式会社 | Component built-in substrate and semiconductor module |
| JP2019047063A (en) | 2017-09-06 | 2019-03-22 | イビデン株式会社 | Printed circuit board and manufacturing method thereof |
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