JP2009200113A

JP2009200113A - Shield wiring circuit board

Info

Publication number: JP2009200113A
Application number: JP2008037734A
Authority: JP
Inventors: Tadao Okawa; 忠男大川
Original assignee: Nitto Denko Corp
Current assignee: Nitto Denko Corp
Priority date: 2008-02-19
Filing date: 2008-02-19
Publication date: 2009-09-03

Abstract

PROBLEM TO BE SOLVED: To provide a shield wiring circuit board where a circuit and a shield material have mutual electrical conduction with sufficiently high connection reliability. SOLUTION: The shield wiring circuit board is constituted by forming the circuit 4 and a cover insulating layer 5 which covers the circuit on a base insulating layer 3, forming an opening 6 in the cover insulating layer 5, stacking an anisotropic film 7 and the shield material 8 on the cover insulating layer 5 in this order, forming a terminal portion 9 at a part of the cover insulating layer 5 of the circuit 4 which is exposed at a bottom part of the opening 6, and electrically connecting the terminal portion 9 and shield material 8 through the anisotropic film 7. COPYRIGHT: (C)2009,JPO&INPIT

Description

本発明はシールド配線回路基板に関し、詳しくは、シールド材と配線回路基板との接続信頼性が向上したシールド配線回路基板に関する。 The present invention relates to a shielded wiring circuit board, and more particularly to a shielded wiring circuit board with improved connection reliability between a shield material and a wired circuit board.

配線回路基板の回路から発生する電磁波は、隣接した回路をアンテナ化する作用があるため、ノイズの発生源となり、機器内部での回路間の誤動作やクロストーク現象を生じさせるばかりでなく、外部機器に対しても影響を及ぼす。また、他の外部機器からの電磁波によって影響を受ける場合もある。このため、例えば、フレキシブル配線回路基板等において、回路から発生する電磁波を遮蔽する対策（シールド対策）が行われており、例えば、シールド材としての金属薄膜を導電性接着剤を用いて基体である配線回路基板に貼り合わせ、同時に、回路のグランド線とシールド材（金属薄膜）とを導通させたものがある（特許文献１〜３）。 The electromagnetic wave generated from the circuit on the printed circuit board acts as an antenna for the adjacent circuit, so it becomes a source of noise, causing malfunctions between circuits inside the device and crosstalk phenomenon, as well as external devices. It also affects. Moreover, it may be affected by electromagnetic waves from other external devices. For this reason, for example, in a flexible printed circuit board or the like, measures (shielding measures) for shielding electromagnetic waves generated from the circuit are taken. For example, a metal thin film as a shielding material is a base using a conductive adhesive. There is one in which a circuit ground line and a shielding material (metal thin film) are made conductive at the same time (Patent Documents 1 to 3).

このような回路のグランド線とシールド材（金属薄膜）とを導通させたタイプのシールド配線回路基板は、通常、配線回路基板の回路を覆うカバー絶縁層に回路のグランド線に達する開口（貫孔）を設けておき、カバー絶縁層上に導電性接着剤の層を介してシールド材を重ねて加熱、加圧を施すことで作製される。すなわち、加熱、加圧によって、シールド材（金属薄膜）が導電性接着剤を介してカバー絶縁層に接着されると同時に、導電性接着剤がカバー絶縁層に設けられた開口に流れ込んで回路のグランド線まで達し、シールド材（金属薄膜）と回路のグランド線が導通する。
特開平７−１２２８８２号公報特開２００３−２９８２８５号公報特開２００６−３１９２１６号公報 A shielded wiring circuit board of a type in which the ground line of such a circuit and a shielding material (metal thin film) are electrically connected usually has an opening (through hole) that reaches the circuit ground line in a cover insulating layer that covers the circuit of the wired circuit board. ) Is provided, and a shield material is stacked on the insulating cover layer through a conductive adhesive layer, and heated and pressurized. That is, by applying heat and pressure, the shielding material (metal thin film) is adhered to the cover insulating layer via the conductive adhesive, and at the same time, the conductive adhesive flows into the opening provided in the cover insulating layer and The ground line is reached, and the shield material (metal thin film) and the circuit ground line become conductive.
Japanese Patent Laid-Open No. 7-122882 JP 2003-298285 A JP 2006-319216 A

ところで、近時の電気機器または電子機器の小型化および高集積化に伴って、配線回路基板においても、回路（導体パターン）の微細化や構成材料の厚み精度など、要求品質が次第に厳しくなってきており、そのために、上記のような回路のグランド線にシールド材（金属薄膜）を導通させたタイプのシールド配線回路基板では、カバー絶縁層に設ける開口の径を小さくする必要が生じ、回路とシールド材の間に十分に高い接続信頼性が得られにくくなってきている。具体的には、回路とシールド材（金属薄膜）間の導通状態が得られない（導通不良）、或いは、導通状態が得られても、環境変化によって、回路とシールド材（金属薄膜）間の抵抗上昇が顕著になり、かかる抵抗上昇により、シールド材（金属薄膜）が新たなノイズ源になるといった問題が生じている。 By the way, with the recent miniaturization and high integration of electrical or electronic devices, the required quality, such as miniaturization of circuits (conductor patterns) and thickness accuracy of constituent materials, has become increasingly severe in printed circuit boards. Therefore, in the shielded wiring circuit board of the type in which the shield material (metal thin film) is conducted to the ground wire of the circuit as described above, it is necessary to reduce the diameter of the opening provided in the cover insulating layer. It has become difficult to obtain sufficiently high connection reliability between shield materials. Specifically, a conduction state between the circuit and the shielding material (metal thin film) cannot be obtained (conductivity failure), or even if a conduction state is obtained, the circuit changes and the shielding material (metal thin film) due to environmental changes. The increase in resistance becomes significant, and this increase in resistance causes a problem that the shield material (metal thin film) becomes a new noise source.

本発明は、かかる事情に鑑みなされたもので、その解決しようとする課題は、回路とシールド材とが十分に高い接続信頼性で導通したシールド配線回路基板を提供することである。 The present invention has been made in view of such circumstances, and a problem to be solved is to provide a shielded wiring circuit board in which a circuit and a shield material are conducted with sufficiently high connection reliability.

本発明者は、上記課題を解決するために、従来のシールド配線回路基板における回路とシールド材間の接続信頼性が低下する原因を調べたところ、カバー絶縁層の開口径が小さくなると、十分な加熱と加圧処理を行っても、カバー絶縁層の開口内に導電性接着剤中のフィラーによる安定な導通路が形成され難いことが分かった。このため、カバー絶縁層の開口内に安定な導通路を確実に形成するという観点から研究を進めた結果、カバー絶縁層の開口内に端子部を設け、該端子部とシールド材（金属薄膜）間に、絶縁性材料からなるフィルム基材中に該基材の厚み方向に貫通する複数の導通路を設けた構造の異方導電性フィルムを介在させ、接着剤層を用いる等の工夫を凝らすことによって、カバー絶縁層の開口内の回路とシールド材（金属薄膜）とが機械的にも電気的にも安定に接続し得ることを見出し、本発明を完成するに到った。 In order to solve the above problems, the present inventor examined the cause of the decrease in the connection reliability between the circuit and the shield material in the conventional shielded wiring circuit board. It has been found that even when heating and pressurizing are performed, it is difficult to form a stable conduction path by the filler in the conductive adhesive in the opening of the insulating cover layer. Therefore, as a result of research from the viewpoint of reliably forming a stable conduction path in the opening of the insulating cover layer, a terminal portion is provided in the opening of the insulating cover layer, and the terminal portion and the shielding material (metal thin film) In between, an anisotropic conductive film having a structure in which a plurality of conductive paths penetrating in the thickness direction of the base material is interposed in a film base material made of an insulating material, and a device such as an adhesive layer is used. Thus, it has been found that the circuit in the opening of the cover insulating layer and the shield material (metal thin film) can be stably connected mechanically and electrically, and the present invention has been completed.

すなわち、本発明は、
（１）ベース絶縁層上に回路と該回路を覆うカバー絶縁層が形成され、
前記カバー絶縁層に開口が形成され、
前記開口の底部に露出する前記回路の上に端子部が形成され、
前記カバー絶縁層上に、片面にシールド材が一体的に設けられた異方導電性フィルムが、前記片面とは反対側の片面をカバー絶縁層に直面させて積層され、
前記異方導電性フィルムは、絶縁性材料からなるフィルム基材中に該基材の厚み方向に貫通する複数の導通路が設けられた構造物であり、
前記異方導電性フィルムが前記カバー絶縁層と端子部に接着し、
前記端子部と前記シールド材が前記異方導電性フィルム中の導通路を介して導通していることを特徴とする、シールド配線回路基板、
（２）カバー絶縁層と異方導電性フィルムが接着剤層を介して接着されており、異方導電性フィルム中の導通路が該接着剤層を貫通して端子部に接触している、上記（１）記載のシールド配線回路基板、
（３）シールド材が接着剤層を介して異方導電性フィルムの片面に接着されており、異方導電性フィルム中の導通路が該接着剤層を貫通してシールド材に接触している、上記（１）又は（２）記載のシールド配線回路基板、
（４）ベース絶縁層上に回路と該回路を覆うカバー絶縁層が形成され、
前記カバー絶縁層に開口が形成され、
前記開口の底部に露出する前記回路の上に端子部が形成され、
前記端子部上に前記開口と略同一面積の異方導電性フィルムが配置され、
前記異方導電性フィルム及びカバー絶縁層上にシールド材が配置され、
前記異方導電性フィルムは、絶縁性材料からなるフィルム基材中に該基材の厚み方向に貫通する複数の導通路が設けられた構造物であり、
前記シールド材が接着剤層を介して前記異方導電性フィルム及びカバー絶縁層上に接着し、
前記異方導電性フィルム中の導通路が前記接着剤層を貫通することで、前記端子部と前記シールド材が導通していることを特徴とする、シールド配線回路基板、
（５）カバー絶縁層の厚みが１０〜５０μｍであり、開口の径（Ｗ）が１００〜２０００μｍである、上記（１）〜（４）のいずれかに記載のシールド配線回路基板、
（６）異方導電性フィルムの導通路が、金属細線により形成されたものである、上記（１）〜（５）のいずれかに記載のシールド配線回路基板、及び
（７）端子部の表面がＡｕ膜またはＳｎ膜である、上記（１）〜（６）のいずれかに記載のシールド配線回路基板、に関する。 That is, the present invention
(1) A circuit and a cover insulating layer covering the circuit are formed on the base insulating layer,
An opening is formed in the insulating cover layer;
A terminal part is formed on the circuit exposed at the bottom of the opening;
On the cover insulating layer, an anisotropic conductive film integrally provided with a shield material on one side is laminated with one side opposite to the one side facing the cover insulating layer,
The anisotropic conductive film is a structure provided with a plurality of conduction paths penetrating in the thickness direction of the base material in a film base material made of an insulating material,
The anisotropic conductive film adheres to the cover insulating layer and the terminal portion,
The shield wiring circuit board, wherein the terminal portion and the shield material are conducted through a conduction path in the anisotropic conductive film,
(2) The insulating cover layer and the anisotropic conductive film are bonded via an adhesive layer, and the conduction path in the anisotropic conductive film passes through the adhesive layer and contacts the terminal portion. The shield wiring circuit board according to the above (1),
(3) The shield material is bonded to one side of the anisotropic conductive film via the adhesive layer, and the conduction path in the anisotropic conductive film passes through the adhesive layer and contacts the shield material. , The shielded wiring circuit board according to the above (1) or (2),
(4) A circuit and a cover insulating layer covering the circuit are formed on the base insulating layer,
An opening is formed in the insulating cover layer;
A terminal part is formed on the circuit exposed at the bottom of the opening;
An anisotropic conductive film having substantially the same area as the opening is disposed on the terminal portion,
A shielding material is disposed on the anisotropic conductive film and the cover insulating layer,
The anisotropic conductive film is a structure provided with a plurality of conduction paths penetrating in the thickness direction of the base material in a film base material made of an insulating material,
The shield material is bonded onto the anisotropic conductive film and the cover insulating layer via an adhesive layer,
A shielded wiring circuit board, wherein the terminal portion and the shield material are electrically connected by a conduction path in the anisotropic conductive film passing through the adhesive layer;
(5) The shield wiring circuit board according to any one of (1) to (4) above, wherein the cover insulating layer has a thickness of 10 to 50 μm and an opening diameter (W) of 100 to 2000 μm.
(6) The shield wiring circuit board according to any one of (1) to (5) above, wherein the conduction path of the anisotropic conductive film is formed of a thin metal wire, and (7) the surface of the terminal portion The present invention relates to the shielded wiring circuit board according to any one of (1) to (6), wherein is an Au film or a Sn film.

本発明によれば、カバー絶縁層の開口径が小さくても、回路とシールド材とが高い接続信頼性で導通し、しかも、高温高湿な環境下に晒されてもかかる高い接続信頼性の導通状態が維持され得る、高い接続信頼性と、優れた耐熱性及び耐湿性とを兼ね備えたシールド配線回路基板を達成することができる。 According to the present invention, even if the opening diameter of the cover insulating layer is small, the circuit and the shield material are electrically connected with high connection reliability, and even when exposed to a high temperature and high humidity environment, such high connection reliability is obtained. It is possible to achieve a shielded wiring circuit board that combines high connection reliability, excellent heat resistance, and moisture resistance, which can maintain a conductive state.

以下、本発明をその好適な実施形態に即して説明する。
本発明のシールド配線回路基板は、シールド材が回路のグランド線に電気的に接続するシールド材を有する配線回路基板であり、基体である「配線回路基板」は、特に限定されず、例えば、（１）フレキシブル配線回路基板、（２）回路付サスペンション板等として用いられる金属基板付フレキシブル配線回路基板、或いは（３）リジッド基板を使用したリジッド配線回路基板等の種々の形態の配線回路基板が含まれる。 Hereinafter, the present invention will be described with reference to preferred embodiments thereof.
The shielded wiring circuit board of the present invention is a wiring circuit board having a shielding material in which the shielding material is electrically connected to the ground line of the circuit, and the “wiring circuit board” as the base is not particularly limited. 1) Flexible wiring circuit board, (2) Flexible wiring circuit board with metal substrate used as suspension board with circuit, etc. (3) Rigid wiring circuit board using rigid board, etc. It is.

図１は本発明の第１例のシールド配線回路基板の模式図（図（ａ）：全体の断面図、図（ｂ）：要部拡大図）であり、金属基板付フレキシブル配線回路基板にシールド材を一体化したものである。 FIG. 1 is a schematic view of a shielded wiring circuit board according to a first example of the present invention (FIG. 1 (a): overall cross-sectional view, FIG. 1 (b): enlarged view of the main part). It is an integrated material.

かかるシールド配線回路基板１０は、金属基板２と、金属基板２の上に形成されるベース絶縁層３と、ベース絶縁層３上に形成される導体パターンからなる回路４と、該回路４を被覆するカバー絶縁層５とを備える。また、回路４はグランド線４ａと信号線４ｂを有し、カバー絶縁層５に形成された開口６の底部にグランド線４ａが露出している。また、片面にシールド材（金属薄膜）８が一体的に設けられた異方導電性フィルム７がカバー絶縁層５に接着されている。 The shield wiring circuit board 10 includes a metal substrate 2, a base insulating layer 3 formed on the metal substrate 2, a circuit 4 formed of a conductor pattern formed on the base insulating layer 3, and the circuit 4. And a cover insulating layer 5. The circuit 4 includes a ground line 4 a and a signal line 4 b, and the ground line 4 a is exposed at the bottom of the opening 6 formed in the cover insulating layer 5. An anisotropic conductive film 7 having a shield material (metal thin film) 8 integrally provided on one side is bonded to the cover insulating layer 5.

一方、カバー絶縁層５の開口６の底部に露出する回路４のグランド線４ａには端子部（パッド）９が形成されており、前記の片面にシールド材（金属薄膜）８が積層された異方導電性フィルム７の一部がカバー絶縁層５の開口６内に埋入して端子部（パッド）９に接着し、回路４のグランド線４ａとシールド材（金属薄膜）８が端子部（パッド）９と異方導電性フィルム７の導通路７ａを介して導通している。 On the other hand, a terminal portion (pad) 9 is formed on the ground line 4a of the circuit 4 exposed at the bottom of the opening 6 of the insulating cover layer 5, and a shield material (metal thin film) 8 is laminated on the one side. A part of the directionally conductive film 7 is embedded in the opening 6 of the insulating cover layer 5 and adhered to the terminal portion (pad) 9, and the ground wire 4 a of the circuit 4 and the shield material (metal thin film) 8 are connected to the terminal portion ( The pad) 9 is electrically connected to the anisotropic conductive film 7 through the conductive path 7a.

本例のシールド配線回路基板１０では、カバー絶縁層５の開口６の底部に露出する回路４に端子部（パッド）９を設け、片面にシールド材（金属薄膜）８が積層された異方導電性フィルム７をカバー絶縁層５と開口６内の端子部（パッド）９に直接接着させている。ここで、異方導電性フィルム７は、絶縁性材料からなるフィルム基材２０中に該基材の厚み方向に貫通する複数の導通路７ａが設けられた構造物であることから、導通路７ａの端部が開口６内の端子部（パッド）９まで確実に達し、グランド線４ａ上の端子部（パッド）９とシールド材８が異方導電性フィルム中の導通路７ａを介して確実に導通する。従って、シールド材８と配線回路基板（基体）１の間に十分に高い接続信頼性が得られ、シールド材８と回路４間の導通不良によって、シールド材８がノイズ源になってしまうような不具合を解消することができる。 In the shielded wiring circuit board 10 of the present example, anisotropic conductivity is provided in which a terminal portion (pad) 9 is provided on the circuit 4 exposed at the bottom of the opening 6 of the cover insulating layer 5 and a shield material (metal thin film) 8 is laminated on one side. The adhesive film 7 is directly bonded to the insulating cover layer 5 and the terminal portion (pad) 9 in the opening 6. Here, the anisotropic conductive film 7 is a structure in which a plurality of conductive paths 7a penetrating in the thickness direction of the base material are provided in the film base 20 made of an insulating material. The end portion of the lead wire reliably reaches the terminal portion (pad) 9 in the opening 6 and the terminal portion (pad) 9 on the ground wire 4a and the shield material 8 are surely connected via the conduction path 7a in the anisotropic conductive film. Conduct. Accordingly, sufficiently high connection reliability is obtained between the shield material 8 and the printed circuit board (base) 1, and the shield material 8 becomes a noise source due to poor conduction between the shield material 8 and the circuit 4. Trouble can be solved.

本発明において、配線回路基板（基体）１におけるベース絶縁層３およびカバー絶縁層５は、例えば、ポリイミド樹脂、アクリル樹脂、ポリエーテルニトリル樹脂、ポリエーテルスルホン樹脂、ポリエチレンテレフタレート樹脂、ポリエチレンナフタレート樹脂、ポリ塩化ビニル樹脂などの合成樹脂が用いられる。これらのうち、感光性樹脂が好ましく用いられ、特に好ましくは、感光性ポリイミド樹脂である。 In the present invention, the base insulating layer 3 and the cover insulating layer 5 in the printed circuit board (base) 1 are, for example, polyimide resin, acrylic resin, polyether nitrile resin, polyether sulfone resin, polyethylene terephthalate resin, polyethylene naphthalate resin, A synthetic resin such as polyvinyl chloride resin is used. Among these, a photosensitive resin is preferably used, and a photosensitive polyimide resin is particularly preferable.

また、ベース絶縁層３およびカバー絶縁層５の厚さは、配線回路基板の具体的用途等に応じて適宜設定されるが、ベース絶縁層３の厚さは、一般的には１〜５０μｍ、好ましくは５〜２５μｍである。また、カバー絶縁層５の厚さはフレキシブル性を確保しながら、回路基板を保護し、信頼性を確保する観点から、一般的には、１０〜５０μｍ程度である。 Further, the thicknesses of the insulating base layer 3 and the insulating cover layer 5 are appropriately set according to the specific application of the printed circuit board, but the thickness of the insulating base layer 3 is generally 1 to 50 μm, Preferably it is 5-25 micrometers. Moreover, the thickness of the insulating cover layer 5 is generally about 10 to 50 μm from the viewpoint of protecting the circuit board and ensuring reliability while ensuring flexibility.

また、回路（導体パターン）４には、例えば、銅、アルミニウム、ニッケル、金、はんだ、またはこれらの合金などの金属が用いられ、好ましくは、銅が用いられる。また、回路（導体パターン）４の厚みは、通常、２〜３０μｍ、好ましくは５〜２０μｍである。また、回路（導体パターン）４の幅は、通常、信号線４ｂにおいては５〜５００μｍ程度であり、グランド線４ａにおいては５０〜５０００μｍ程度である。なお、グランド線４ａは、シールド層と接続する部分（すなわち、カバー絶縁層の開口６の直下）においてのみパターン幅を広げ、その他の部分は、信号線４ｂのパターン幅と同じにしてもよい。 For the circuit (conductor pattern) 4, for example, a metal such as copper, aluminum, nickel, gold, solder, or an alloy thereof is used, and copper is preferably used. The thickness of the circuit (conductor pattern) 4 is usually 2 to 30 μm, preferably 5 to 20 μm. The width of the circuit (conductor pattern) 4 is normally about 5 to 500 μm for the signal line 4 b and about 50 to 5000 μm for the ground line 4 a. Note that the ground line 4a may be widened only in a portion connected to the shield layer (that is, immediately below the opening 6 of the cover insulating layer), and the other portions may have the same pattern width as the signal line 4b.

カバー絶縁層５に形成される開口６の形状や大きさは回路（導体パターン）４のグランド線４ａの幅に応じて決定される。通常、開口６の平面形状は正方形、矩形、円形等の一般的形状であり、また、開口６の径（図１中のＷ）は、一般的には、開口６の平面形状が正方形や矩形または円形である場合、通常、その一辺または直径が１００〜２０００μｍ程度であり、好ましくは１００〜３００μｍ程度である。 The shape and size of the opening 6 formed in the insulating cover layer 5 are determined according to the width of the ground line 4 a of the circuit (conductor pattern) 4. Usually, the planar shape of the opening 6 is a general shape such as a square, a rectangle, or a circle, and the diameter of the opening 6 (W in FIG. 1) is generally the square shape or the rectangular shape of the opening 6. Or when it is circular, the one side or diameter is about 100-2000 micrometers normally, Preferably it is about 100-300 micrometers.

端子部（パッド）９は、公知の導電性材料が用いられ、多くの場合、Ａｕ、Ｎｉ、Ｓｎ、半田等の導電性に優れる金属材料が用いられる。また、端子部（パッド）９の表面層は、極めて良好な導電性を示すＡｕ膜またはＳｎ膜で構成するのが好ましく、Ａｕ膜が特に好ましい。なお、回路（導体パターン）４が銅からなる場合、Ａｕ薄膜との相互反応による導電性の低下を防止するために、銅導体層とＡｕ薄膜の間にニッケル薄膜等のバリア層を介在させるのが好ましい。端子部（パッド）の平面形状は、正方形、矩形、円形等の一般的形状であり、また、端子部（パッド）の大きさは、導体層の幅等に応じて適宜決定され、一般的には、端子部の平面形状が正方形や矩形または円形である場合、通常、その一辺または直径が１００〜２０００μｍ程度であり、好ましくは１００〜３００μｍ程度である。 For the terminal portion (pad) 9, a known conductive material is used, and in many cases, a metal material having excellent conductivity such as Au, Ni, Sn, solder or the like is used. Further, the surface layer of the terminal portion (pad) 9 is preferably composed of an Au film or an Sn film exhibiting extremely good conductivity, and an Au film is particularly preferable. When the circuit (conductor pattern) 4 is made of copper, a barrier layer such as a nickel thin film is interposed between the copper conductor layer and the Au thin film in order to prevent a decrease in conductivity due to the interaction with the Au thin film. Is preferred. The planar shape of the terminal portion (pad) is a general shape such as a square, a rectangle, or a circle, and the size of the terminal portion (pad) is appropriately determined according to the width of the conductor layer, etc. In the case where the planar shape of the terminal portion is square, rectangular or circular, one side or the diameter is usually about 100 to 2000 μm, preferably about 100 to 300 μm.

端子部(パッド）９の厚みは、通常、接続信頼性及びコストの点から０．０１μｍ〜１０μｍ程度である。なお、前記のとおり、カバー絶縁層５は回路基板のフレキシブル性、保護及び信頼性等の点から前述の厚み（１０〜５０μｍ程度）が必要であり、このことから、端子部(パッド）９とカバー絶縁層５の間には、通常、１０〜５０μｍ程度の段差が生じることとなる。 The thickness of the terminal portion (pad) 9 is usually about 0.01 μm to 10 μm from the viewpoint of connection reliability and cost. As described above, the insulating cover layer 5 must have the above-described thickness (about 10 to 50 μm) from the viewpoint of flexibility, protection, and reliability of the circuit board. Normally, a step of about 10 to 50 μm is generated between the insulating cover layers 5.

配線回路基板（基体）１は公知の方法で製造される。なお、ベース絶縁層３やカバー絶縁層５に感光性樹脂を使用することにより、感光性ポリアミック酸樹脂溶液などの感光性樹脂溶液を塗布し、これを露光、現像、乾燥硬化することにより、容易に所望のパターンに形成することができ、有利である。また、ベース絶縁層３は、予め絶縁材料からなるフィルムをベース絶縁層３の形状に適合するように形成し、これを金属基板２の上に粘着する（必要により接着剤層を介して貼着する）方法も好適である。 The printed circuit board (base) 1 is manufactured by a known method. In addition, by using a photosensitive resin for the base insulating layer 3 and the cover insulating layer 5, a photosensitive resin solution such as a photosensitive polyamic acid resin solution is applied, and this is easily exposed, developed, and dried and cured. Can be formed into a desired pattern. The insulating base layer 3 is formed by previously forming a film made of an insulating material so as to conform to the shape of the insulating base layer 3, and sticks it on the metal substrate 2 (adhering via an adhesive layer if necessary). The method is also suitable.

回路（導体パターン）４は、例えば、アディティブ法、セミアディティブ法、サブトラクティブ法などの公知のパターンニング法によって、所定パターンの導体パターンを形成する。なお、回路（導体パターン）４には、必要により、無電解メッキによって、ニッケルメッキ層で被覆してもよい。 The circuit (conductor pattern) 4 forms a conductor pattern having a predetermined pattern by a known patterning method such as an additive method, a semi-additive method, or a subtractive method. The circuit (conductor pattern) 4 may be covered with a nickel plating layer by electroless plating if necessary.

端子部（パッド）９の形成方法は特に限定はされないが、例えば、電解メッキ、無電解メッキなどの公知のメッキ法にて形成することができる。 The method for forming the terminal portion (pad) 9 is not particularly limited, but it can be formed by a known plating method such as electrolytic plating or electroless plating.

図２（ａ）、（ｂ）は本発明で使用する異方導電性フィルム７の平面図（図（ａ））と断面図（図（ｂ））である。前述のとおり、異方導電性フィルム７は、絶縁性材料からなるフィルム基材２０中に該基材の厚み方向に貫通する複数の導通路７ａが設けられた構造物であるが、導通路７ａの断面形状は、図２（ａ）に示されるような円形の他、多角形等の他の形状であってもよい。導通路７ａの太さ（断面径）、導通路の配列ピッチ（隣接する導通路の軸線間の距離）等は、配線回路基板のカバー絶縁層５に設ける開口６の大きさを考慮して、少なくとも一本の導通路７ａが開口６内に入り込むように設定される。一般的には、導通路７ａの太さ（断面径）は１０〜１００μｍ（好ましくは１０〜５０μｍ）の範囲内から選択され、配列ピッチは３０〜２００μｍ（好ましくは３０〜１００μｍ）の範囲内から選択される。また、導通路７ａの配列パターンは、密に集合した状態であれば、特に限定はされないが、図２（ａ）に示されるような千鳥配列状の他、マトリクス状等の規則性の高い配列パターンがよい。 2A and 2B are a plan view (FIG. 2A) and a cross-sectional view (FIG. 2B) of the anisotropic conductive film 7 used in the present invention. As described above, the anisotropic conductive film 7 is a structure in which a plurality of conductive paths 7a penetrating in the thickness direction of the base material are provided in the film base 20 made of an insulating material. The cross-sectional shape may be a circular shape as shown in FIG. 2A or another shape such as a polygon. Considering the size of the opening 6 provided in the insulating cover layer 5 of the printed circuit board, the thickness (cross-sectional diameter) of the conductive path 7a, the arrangement pitch of the conductive paths (distance between the axes of the adjacent conductive paths), etc. At least one conduction path 7 a is set so as to enter the opening 6. In general, the thickness (cross-sectional diameter) of the conduction path 7a is selected from the range of 10 to 100 μm (preferably 10 to 50 μm), and the arrangement pitch is from the range of 30 to 200 μm (preferably 30 to 100 μm). Selected. Further, the arrangement pattern of the conduction paths 7a is not particularly limited as long as it is in a densely assembled state, but in addition to the staggered arrangement as shown in FIG. The pattern is good.

図３（ａ）、（ｂ）は本発明で使用する異方導電性フィルム７の別の態様を示しており、該異方導電性フィルムは第１の絶縁性材料からなるフィルム基材２０中に、複数の導通路７ａが、互いに絶縁された状態で、フィルム基材２０を厚み方向に貫通した状態で配置され、各導通路７ａの、フィルム基材２０の両主面（表裏面）に露出する端面を除く表面が第２の絶縁性材料２１で被覆されている。導通路７ａの配列パターンはマトリクス状である。 3 (a) and 3 (b) show another embodiment of the anisotropic conductive film 7 used in the present invention, and the anisotropic conductive film is in the film base 20 made of the first insulating material. In addition, a plurality of conductive paths 7a are arranged in a state of penetrating the film substrate 20 in the thickness direction in a state of being insulated from each other, and on both main surfaces (front and back surfaces) of the film substrate 20 of each conductive path 7a. The surface excluding the exposed end face is covered with the second insulating material 21. The arrangement pattern of the conduction paths 7a is a matrix.

本発明において、異方導電性フィルム７は、通常、フィルム基材２０が接着性を有する。従って、フィルム基材２０を構成する絶縁性材料は、そのままの状態で接着性を示すか、あるいはそのままの状態では接着性を示さないが、加熱および／または加圧により接着可能となる絶縁性材料であり、例えば、加熱および／または加圧により融着および／または圧着する熱可塑性樹脂や、加熱により溶融、硬化して接着する熱硬化性樹脂が用いられる。具体的には、熱可塑性ポリイミド樹脂、エポキシ樹脂、ポリエーテルイミド樹脂、ポリアミド樹脂、シリコーン樹脂、フェノキシ樹脂、アクリル樹脂、ポリカルボジイミド樹脂、フッ素樹脂、ポリエステル樹脂、ポリウレタン樹脂等が挙げられる。 In the present invention, the anisotropically conductive film 7 usually has the film base 20 having adhesiveness. Therefore, the insulating material constituting the film substrate 20 exhibits an adhesive property as it is, or does not exhibit an adhesive property as it is, but can be bonded by heating and / or pressure. For example, a thermoplastic resin that is fused and / or pressure-bonded by heating and / or pressurization, or a thermosetting resin that is melted, cured, and bonded by heating is used. Specifically, thermoplastic polyimide resin, epoxy resin, polyetherimide resin, polyamide resin, silicone resin, phenoxy resin, acrylic resin, polycarbodiimide resin, fluorine resin, polyester resin, polyurethane resin, and the like can be given.

接着性を有する絶縁性材料が、熱可塑性樹脂からなる場合、端子部９との接合部を再加熱して樹脂を可塑化することにより、端子部９との接着を解くことができる。よって、端子部（パッド）９と異方導電性フィルムの接着状態が好ましくない場合（基材樹脂とパッドとの接着が不完全な場合や、導通路７ａの端部とパッドとの接触が不完全な場合）、接合のやり直し（リワーク）を行うことができる。一方、熱硬化性樹脂からなる場合、高温になるほど硬化が進むので、高温での接着力が高くなり、接続信頼性が一層向上する。 In the case where the insulating material having adhesiveness is made of a thermoplastic resin, the bonding with the terminal portion 9 can be released by reheating the joint portion with the terminal portion 9 to plasticize the resin. Therefore, when the bonding state between the terminal portion (pad) 9 and the anisotropic conductive film is not preferable (when the bonding between the base resin and the pad is incomplete, the contact between the end portion of the conduction path 7a and the pad is not good). When complete), reworking (rework) can be performed. On the other hand, in the case of a thermosetting resin, the curing proceeds as the temperature increases, so that the adhesive strength at a high temperature is increased and the connection reliability is further improved.

なお、図３の形態の異方導電性フィルムの場合、第１の絶縁性材料と第２の材料を適宜選択することにより、フィルム基材が単一の材料で構成されたものに比べて、異方導電性フィルムの強度、耐熱性、誘電特性、応力緩和特性の点で優れたものとなる。よって、図３の形態の異方導電性フィルムを用いることにより、結果的に、強度的にも導通性の点からもより信頼性の高い接続を得ることが可能である。具体的には、フィルム基材２０と導通路７ａとの接着性を良好とするためには、例えば、第１の絶縁性材料としてポリエーテルイミド樹脂を、第２の材料としてポリアミド樹脂を選択する。また、異方導電性フィルムの強度を良好とするためには、例えば、第１の絶縁性材料としてポリイミド樹脂を、第２の材料としてエポキシ樹脂を選択する。また、異方導電性フィルムの耐熱性を良好とするためには、例えば、第１の絶縁性材料としてポリイミド樹脂やポリカルボジイミド樹脂を、第２の材料としてポリエステル樹脂やポリウレタン樹脂を選択する。 In the case of the anisotropic conductive film in the form of FIG. 3, by appropriately selecting the first insulating material and the second material, the film base is made of a single material, The anisotropic conductive film is excellent in strength, heat resistance, dielectric properties, and stress relaxation properties. Therefore, by using the anisotropic conductive film in the form shown in FIG. 3, it is possible to obtain a connection with higher reliability in terms of strength and conductivity. Specifically, in order to improve the adhesion between the film substrate 20 and the conduction path 7a, for example, a polyetherimide resin is selected as the first insulating material and a polyamide resin is selected as the second material. . In order to improve the strength of the anisotropic conductive film, for example, a polyimide resin is selected as the first insulating material, and an epoxy resin is selected as the second material. In order to improve the heat resistance of the anisotropic conductive film, for example, a polyimide resin or a polycarbodiimide resin is selected as the first insulating material, and a polyester resin or a polyurethane resin is selected as the second material.

異方導電性フィルム７のフィルム基材２０には、各種の充填剤、可塑剤等あるいはゴム材料が添加されていてもよく、充填剤としては、例えば、ＳｉＯ_２、Ａｌ_２Ｏ_３、可塑剤としては、例えば、ＴＣＰ（リン酸トリクレシル）、ＤＯＰ（フタル酸ジオクチル）、ゴム材料としては、例えばＮＢＳ（アクリロニトリルブタジエンゴム）、ＳＢＳ（スチレン−ブタジエン−スチレン−ブロック共重合体）等が挙げられる。 Various fillers, plasticizers and the like or rubber materials may be added to the film base 20 of the anisotropic conductive film 7. Examples of the filler include SiO ₂ , Al ₂ O ₃ , and plasticizers. Examples of the rubber material include TCP (tricresyl phosphate) and DOP (dioctyl phthalate), and examples of the rubber material include NBS (acrylonitrile butadiene rubber) and SBS (styrene-butadiene-styrene-block copolymer).

異方導電性フィルム７の導通路７ａの構成材料としては、公知の材料が挙げられ、例えば、銅、金、アルミニウム、ニッケル、ハンダ等の金属材料が挙げられる。また、これら金属材料とポリイミド樹脂、エポキシ樹脂、アクリル樹脂、フッ素樹脂等の有機材料との混合物を用いてもよい。電気特性の点で金属材料が好ましく、特に金、銅などの良導体を用いるのが好ましい。 Examples of the constituent material of the conductive path 7a of the anisotropic conductive film 7 include known materials, and examples thereof include metal materials such as copper, gold, aluminum, nickel, and solder. Moreover, you may use the mixture of these metal materials and organic materials, such as a polyimide resin, an epoxy resin, an acrylic resin, and a fluororesin. A metal material is preferable from the viewpoint of electrical characteristics, and it is particularly preferable to use a good conductor such as gold or copper.

図４（ａ）、（ｂ）は導通路７ａの好適な態様を示している。図４（ａ）は、導通路７ａの大部分を銅（Ｃｕ）で形成し、導通路７ａの両端部をＮｉ／Ａｕメッキで形成したものである。また、図４（ｂ）は、導通路７ａの両端部を除く大部分を銅（Ｃｕ）で形成し、導通路の両端部をＮｉ／ハンダメッキで形成したものである。図４（ａ）の形態とした場合、前記した表面をＡｕ膜とする端子部（パッド）９の好ましい形態と組み合わせることで、導通路７ａの端部とパッド９の接触がＡｕ同士の接触となり、極めて良好な導通性が得られる。一方、図４（ｂ）の形態とした場合、フィルムの主面をパッドに熱圧着または圧着して、フィルムの基材樹脂を端子部（パッド）９に接着した後、接合部を加熱するとハンダが速やかに溶融して端子部（パッド）９に融着する。よって、一旦、端子部（パッド）９に接着した基材樹脂が可塑化して接着が解かれてしまうような事態を生じることなく、導通路の端部がパッドに融着して、強固な接続を得ることができる。なお、Ｎｉ／ハンダメッキに代えて、Ｎｉ／Ｓｎメッキを形成してもよく、同様の効果を得ることができる。 4 (a) and 4 (b) show a preferred embodiment of the conduction path 7a. In FIG. 4A, most of the conduction path 7a is formed of copper (Cu), and both ends of the conduction path 7a are formed by Ni / Au plating. FIG. 4B shows a case where most of the conduction path 7a except for both ends is formed of copper (Cu), and both ends of the conduction path are formed by Ni / solder plating. In the case of the form shown in FIG. 4A, the contact between the end of the conduction path 7a and the pad 9 becomes a contact between Au by combining the above-described surface with the preferable form of the terminal part (pad) 9 having the Au film. Very good electrical conductivity can be obtained. On the other hand, in the case of the configuration shown in FIG. 4B, the main surface of the film is thermocompression-bonded or pressure-bonded to the pad, the base resin of the film is bonded to the terminal portion (pad) 9, and then the joint is heated to solder. Quickly melts and is fused to the terminal portion (pad) 9. Therefore, the end portion of the conduction path is fused to the pad without causing a situation in which the base resin once adhered to the terminal portion (pad) 9 is plasticized and unbonded, and a strong connection is obtained. Can be obtained. In place of Ni / solder plating, Ni / Sn plating may be formed, and the same effect can be obtained.

異方導電性フィルム７は、フィルム基材２０に貫孔を開け、該貫孔内に金属材料をメッキで析出させる方法によって導通路７ａを形成したものでもよいが、金属細線によって導通路７ａを形成したものが好ましい。このような金属細線による導通路を形成した異方導電性フィルムは、金属細線に絶縁性材料からなる被覆層を形成して絶縁導線とし、該絶縁導線を芯材にロール状に巻いて、加熱および／または加圧を施すことで絶縁性材料からなる被覆層どうしが融着および／または圧着したロール状物を作成し、該ロール状物を絶縁導線の軸線と角度をなして交差する平面を断面として所定のフィルム厚さに切断する方法によって製造することができる。図３の態様の異方導電性フィルムの場合、絶縁導線として、金属細線に第２の絶縁性材料からなる被覆層と第１の絶縁性材料からなる被覆層を順次形成して絶縁導線を使用すればよい。なお、図４の態様の導通路を有する異方導電性フィルムは、メッキで導通路を形成する場合、銅、Ｎｉ、ハンダ（Ａｕ）の順に３段階のメッキを行えばよく、金属細線で導通路を形成する場合、銅細線による導通路の端部を、酸或いはアルカリによるケミカルエッチング等を用いて選択的にエッチングし、エッチングにより除去された凹部に、Ｎｉ、ハンダ（Ａｕ）の順にメッキを行う方法により得ることができる。 The anisotropic conductive film 7 may have a conductive path 7a formed by forming a through-hole in the film base 20 and depositing a metal material in the through-hole by plating, but the conductive path 7a is formed by a thin metal wire. Those formed are preferred. An anisotropic conductive film having a conductive path formed of such a fine metal wire is formed by forming a coating layer made of an insulating material on the fine metal wire to form an insulated conductor, and then winding the insulated conductor in a roll shape around the core material, And / or pressurizing to create a roll-like material in which the covering layers made of an insulating material are fused and / or pressure-bonded, and a plane intersecting the roll-like material at an angle with the axis of the insulated conductor. It can be manufactured by a method of cutting into a predetermined film thickness as a cross section. In the case of the anisotropic conductive film of the embodiment shown in FIG. 3, an insulated conductor is used by sequentially forming a coating layer made of the second insulating material and a coating layer made of the first insulating material on the thin metal wire as the insulated conductor. do it. Note that the anisotropic conductive film having the conduction path of the embodiment shown in FIG. 4 may be plated in three stages in the order of copper, Ni, and solder (Au) when the conduction path is formed by plating, and is conducted with a thin metal wire. When forming the passage, the end of the conductive path made of the copper fine wire is selectively etched using chemical etching with acid or alkali, and the recesses removed by the etching are plated in the order of Ni and solder (Au). It can be obtained by the method to be performed.

異方導電性フィルム７の厚みは、厚みが小さすぎると、導通路と回路（導体パターン）間の導電性、導通路とシールド材間の導電性等が不十分となる恐れがあり、また、大きすぎると接続抵抗が高くなり、電気的信頼性が低下するおそれがある。したがって、一般的には１０〜２００μｍ程度、好ましくは１０〜１００μｍ程度であるが、特に、開口６内の端子部９の表面とカバー絶縁層５の表面間の段差を吸収しつつ、導通路７と端子部９間に高信頼性の導通状態を確保する観点から、より好ましくは１５〜８０μｍであり、とりわけ好ましくは２０〜７０μｍである。 If the thickness of the anisotropic conductive film 7 is too small, the conductivity between the conduction path and the circuit (conductor pattern), the conductivity between the conduction path and the shield material may be insufficient, If it is too large, the connection resistance becomes high and the electrical reliability may be lowered. Therefore, it is generally about 10 to 200 μm, preferably about 10 to 100 μm, and in particular, the conduction path 7 while absorbing the step between the surface of the terminal portion 9 and the surface of the cover insulating layer 5 in the opening 6. From the viewpoint of securing a highly reliable conduction state between the terminal portions 9, the thickness is more preferably 15 to 80 μm, and particularly preferably 20 to 70 μm.

異方導電性フィルム７は、フィルム基材が圧着のみで接着するものであれば、異方導電性フィルム７の主面を被接続体に接触させて加圧するだけでよい。フィルム基材が加熱、加圧で接着するものであれば、加熱、加圧を行う。より高い接続信頼性を得るためには、加熱及び加圧を行うのが好ましい。 As long as the anisotropic conductive film 7 is a film base material that adheres only by pressure bonding, the main surface of the anisotropic conductive film 7 may be brought into contact with the body to be connected and pressed. If the film substrate is bonded by heating and pressing, heating and pressing are performed. In order to obtain higher connection reliability, it is preferable to perform heating and pressurization.

シールド材（金属薄膜）８としては、例えば、銅、クロム、ニッケル、金、銀、白金、パラジウム、チタン、タンタル、はんだ、またはこれらの合金などの薄膜を用いることができ、中でも、銅、銀が好ましい。また、シールド材（金属薄膜）８の厚みは１〜１８μｍが好ましく、２〜１２μｍがより好ましい。厚みが１μｍ未満では、電磁シールド効果が低下する傾向となり、厚みが１８μｍを超えると基板が厚くなり過ぎることから、可撓性が得られにくくなる傾向となるため、好ましくない。シールド材（金属薄膜）８は、電解メッキ、無電解メッキなどのメッキ法や、スパッタリング法、真空蒸着法、イオンプレーティング法などの真空成膜法により形成することができる。なお、シールド材（金属薄膜）８は異方導電性フィルム７をカバー絶縁層５に接着する前に、異方導電性フィルム７の片面に形成（積層）しておいても、異方導電性フィルム７をカバー絶縁層５に接着した後に、異方導電性フィルム７の片面に形成（積層）してもよい。異方導電性フィルム７をカバー絶縁層５に接着する前に、シールド材（金属薄膜）８を異方導電性フィルム７の片面に形成（積層）する態様の場合、異方導電性フィルムとシールド材を一括して打ち抜き加工できる等の点で好ましい。 As the shielding material (metal thin film) 8, for example, a thin film such as copper, chromium, nickel, gold, silver, platinum, palladium, titanium, tantalum, solder, or an alloy thereof can be used. Is preferred. Moreover, 1-18 micrometers is preferable and, as for the thickness of the shielding material (metal thin film) 8, 2-12 micrometers is more preferable. If the thickness is less than 1 μm, the electromagnetic shielding effect tends to be reduced, and if the thickness exceeds 18 μm, the substrate becomes too thick, so that flexibility tends to be difficult to obtain. The shield material (metal thin film) 8 can be formed by a plating method such as electrolytic plating or electroless plating, or a vacuum film forming method such as sputtering, vacuum deposition, or ion plating. The shield material (metal thin film) 8 may be formed (laminated) on one side of the anisotropic conductive film 7 before the anisotropic conductive film 7 is bonded to the cover insulating layer 5. After the film 7 is bonded to the insulating cover layer 5, it may be formed (laminated) on one side of the anisotropic conductive film 7. In the case of a mode in which a shield material (metal thin film) 8 is formed (laminated) on one side of the anisotropic conductive film 7 before adhering the anisotropic conductive film 7 to the insulating cover layer 5, the anisotropic conductive film and the shield This is preferable in that the material can be punched in one batch.

前記図１の第１例のシールド配線回路基板１０では、カバー絶縁層５上に、例えば、片面にシールド材（金属薄膜）８が積層された異方導電性フィルム７を載置した状態で、加圧するか、又は、加圧及び加熱をすることで、図１に示されるように、異方導電性フィルム７がカバー絶縁層５に接着し、異方導電性フィルム７の一部がカバー絶縁層５の開口６の内部で回路４の一部に形成した端子部（パッド）９に接着して、シールド材が回路と電気的に導通した状態で回路基板に強固に一体化したシールド配線回路基板が得られる。 In the shield wiring circuit board 10 of the first example of FIG. 1, on the insulating cover layer 5, for example, an anisotropic conductive film 7 in which a shield material (metal thin film) 8 is laminated on one side is placed, By applying pressure or by applying pressure and heating, the anisotropic conductive film 7 adheres to the insulating cover layer 5 as shown in FIG. 1, and a part of the anisotropic conductive film 7 covers the insulation. A shield wiring circuit which is bonded to a terminal portion (pad) 9 formed in a part of the circuit 4 inside the opening 6 of the layer 5 and is firmly integrated with the circuit board in a state where the shield material is electrically connected to the circuit. A substrate is obtained.

ここで、接着に要する加圧力は、一般的には、０．１〜１ｋｇｆ／ｍｍ^２程度であり、好ましくは０．１〜０．８ｋｇｆ／ｍｍ^２程度である。また、加圧及び加熱を行う場合の加熱温度は、一般的には２００〜３５０℃程度であり、好ましくは２００〜３００℃程度である。 Here, the applied pressure required for adhesion is generally about 0.1 to 1 kgf / mm ² , preferably about 0.1 to 0.8 kgf / mm ² . Moreover, the heating temperature in the case of performing pressurization and heating is generally about 200 to 350 ° C., and preferably about 200 to 300 ° C.

なお、異方導電性フィルム７のカバー絶縁層５への接着作業は少なくとも異方導電性フィルム７の導通路７ａの端部が端子部（パッド）９に接触する状態となるように行えばよいが、導通路７ａの端部が端子部（パッド）９に融着するように加熱を行うのが、より高い接続信頼性を得る上で好ましい。 In addition, what is necessary is just to perform the adhesion | attachment work to the cover insulating layer 5 of the anisotropic conductive film 7 so that the edge part of the conduction path 7a of the anisotropic conductive film 7 may be in the state which contacts the terminal part (pad) 9. FIG. However, in order to obtain higher connection reliability, it is preferable to perform heating so that the end of the conduction path 7 a is fused to the terminal portion (pad) 9.

図５は本発明の第２例のシールド配線回路基板の模式断面図であり、図において、図１（ｂ）と同一符号は同一または相当する部分を示す。 FIG. 5 is a schematic cross-sectional view of a shielded circuit board according to a second example of the present invention. In the figure, the same reference numerals as those in FIG. 1B denote the same or corresponding parts.

本第２例のシールド配線回路基板３０では、カバー絶縁層５上に予め接着剤層１２Ａを設け、異方導電性フィルム７のカバー絶縁層５への圧着（接着）を接着剤層１２Ａを介して行っている。すなわち、カバー絶縁層５／接着剤層１２Ａ／異方導電性フィルム７の積層構造を形成後、加圧、或いは、加圧及び加熱を行うことにより、異方導電性フィルム７とカバー絶縁層５が接着剤層１２Ａを介して接着し、異方導電性フィルム７中のフィルム基材２０よりも剛性の高い導通路７ａが接着剤層１２Ａを突き破って端子部（パッド）９に接触している。よって、カバー絶縁層５と異方導電性フィルム７とが接着剤層１２Ａによって強固に接着した状態で、異方導電性フィルム７の導通路７ａが端子部（パッド）９に接触しており、異方導電性フィルム７と端子部（パッド）９間が電気的にも機械的にもより高い信頼性で接続した接続構造が得られる。 In the shielded wiring circuit board 30 of the second example, an adhesive layer 12A is provided in advance on the insulating cover layer 5, and the anisotropic conductive film 7 is bonded (bonded) to the insulating cover layer 5 via the adhesive layer 12A. Is going. That is, after forming the laminated structure of the cover insulating layer 5 / adhesive layer 12A / anisotropic conductive film 7, the anisotropic conductive film 7 and the cover insulating layer 5 are formed by pressurization or pressurization and heating. Is bonded via the adhesive layer 12A, and the conductive path 7a having higher rigidity than the film base 20 in the anisotropic conductive film 7 penetrates the adhesive layer 12A and is in contact with the terminal portion (pad) 9. . Therefore, the conductive path 7a of the anisotropic conductive film 7 is in contact with the terminal portion (pad) 9 in a state where the cover insulating layer 5 and the anisotropic conductive film 7 are firmly bonded by the adhesive layer 12A. A connection structure in which the anisotropic conductive film 7 and the terminal portion (pad) 9 are connected with higher reliability both electrically and mechanically is obtained.

接着剤層１２Ａは一般的な樹脂及び金属に対して接着性を有する、高耐熱性の接着剤であれば、制限なく使用することができる。具体的には、エポキシ樹脂、アクリル樹脂、熱可塑性ポリイミド等が挙げられ、中でも、安価なエポキシ樹脂が好ましい。接着剤層１２Ａの厚みは、十分な接着力を得る観点から、一般的には５〜５０μｍ程度であり、好ましくは１０〜２５μｍ程度である。なお、ここでの厚みは、カバー絶縁層５上への塗布厚み、すなわち、カバー絶縁層５に異方導電性フィルム７を該接着剤層を介して圧着する前の厚みである。 The adhesive layer 12A can be used without limitation as long as it is a highly heat-resistant adhesive having adhesion to general resins and metals. Specific examples include an epoxy resin, an acrylic resin, a thermoplastic polyimide, and the like. Among these, an inexpensive epoxy resin is preferable. The thickness of the adhesive layer 12A is generally about 5 to 50 μm, preferably about 10 to 25 μm, from the viewpoint of obtaining sufficient adhesive force. In addition, the thickness here is a coating thickness on the cover insulating layer 5, that is, a thickness before the anisotropic conductive film 7 is pressure-bonded to the cover insulating layer 5 via the adhesive layer.

圧着作業における加圧、或いは、加圧及び加熱の条件は、前述の第１例のシールド配線回路基板での条件と同等でよい。 The pressurization in the crimping operation, or the conditions of pressurization and heating may be the same as those in the shield wiring circuit board of the first example described above.

図６は本発明の第３例のシールド配線回路基板の模式断面図であり、図において、図１（ｂ）と同一符号は同一または相当する部分を示す。 FIG. 6 is a schematic cross-sectional view of a shielded circuit board according to a third example of the present invention. In the figure, the same reference numerals as those in FIG. 1B indicate the same or corresponding parts.

本第３例のシールド配線回路基板４０では、異方導電性フィルム７に接着剤層１２Ｂを介してシールド材（金属薄膜）８を接着しておき、かかる異方導電性フィルム７／接着剤層１２Ｂ／シールド材（金属薄膜）８の積層構造を形成後、加圧、或いは、加圧及び加熱を行うことで、異方導電性フィルム７とシールド材（金属薄膜）８間の接着（一体化）と導通を行ったものである。すなわち、加圧、或いは、加圧及び加熱を行うことで、異方導電性フィルム７とシールド材（金属薄膜）８とが接着剤層１２Ｂを介して接着するとともに、異方導電性フィルム７中のフィルム基材２０よりも剛性の高い導通路７ａは接着剤層１２Ｂを突き破ってシールド材（金属薄膜）８に接触するため、異方導電性フィルム７とシールド材（金属薄膜）８間が電気的にも機械的にもより高い信頼性で接続した接続構造が得られる。 In the shielded wiring circuit board 40 of the third example, a shield material (metal thin film) 8 is bonded to the anisotropic conductive film 7 via an adhesive layer 12B, and the anisotropic conductive film 7 / adhesive layer is provided. After forming the laminated structure of 12B / shield material (metal thin film) 8, pressurization, or pressurization and heating are performed to bond (unify) the anisotropic conductive film 7 and shield material (metal thin film) 8 ) And conduction. That is, by applying pressure, or by applying pressure and heating, the anisotropic conductive film 7 and the shielding material (metal thin film) 8 are bonded via the adhesive layer 12B, and in the anisotropic conductive film 7 Since the conductive path 7a having higher rigidity than the film base material 20 penetrates the adhesive layer 12B and comes into contact with the shield material (metal thin film) 8, the electrical connection between the anisotropic conductive film 7 and the shield material (metal thin film) 8 is electrically performed. Connection structure with higher reliability both in terms of mechanical and mechanical properties can be obtained.

接着剤層１２Ｂには、一般的な樹脂及び金属に対して接着性を有する、高耐熱性の接着剤であれば制限なく使用することができ、具体的には、前記接着剤層１２Ａの具体例として挙げた接着剤と同様のものが挙げられ、また、接着剤層１２Ｂの厚みも、前記接着剤層１２Ａのそれと同等でよい。また、接着剤層１２Ｂはシールド材８の片面に予め形成しておくことができる。なお、圧着作業における加圧、或いは、加圧及び加熱の条件は、前述の第１例のシールド配線回路基板での条件と同等でよい。 The adhesive layer 12B can be used without limitation as long as it is a high heat-resistant adhesive having adhesiveness to general resins and metals. The adhesive similar to the adhesive mentioned as an example is mentioned, and the thickness of the adhesive layer 12B may be equal to that of the adhesive layer 12A. Further, the adhesive layer 12 B can be formed in advance on one side of the shield material 8. Note that the pressure in the crimping operation, or the conditions of the pressure and heating may be the same as those in the shield wiring circuit board of the first example described above.

なお、本第３例では、シールド材（金属薄膜）８を接着剤層を介して異方導電性フィルム７に一体化するので、シールド材（金属薄膜）８としては、通常、金属箔が使用される。金属箔の構成金属は、前記で説明した、銅、クロム、ニッケル、金、銀、白金、パラジウム、チタン、タンタル、はんだ、またはこれらの合金等が好適である。 In the third example, since the shield material (metal thin film) 8 is integrated with the anisotropic conductive film 7 via the adhesive layer, a metal foil is usually used as the shield material (metal thin film) 8. Is done. The constituent metal of the metal foil is preferably copper, chromium, nickel, gold, silver, platinum, palladium, titanium, tantalum, solder, or an alloy thereof described above.

図７、８は本発明の第４例のシールド配線回路基板の要部断面の模式図であり、図７はシールド材の圧着作業前の状態図、図８はシールド材の圧着作業後の状態図である。これらの図において、図１と同一符号は同一又は相当する部分を示す。 7 and 8 are schematic views of the cross-section of the main part of the shielded wiring circuit board of the fourth example of the present invention, FIG. 7 is a state diagram before the shield material is crimped, and FIG. 8 is a state after the shield material is crimped. FIG. In these drawings, the same reference numerals as those in FIG. 1 denote the same or corresponding parts.

かかる第４例のシールド配線回路基板５０は、カバー絶縁層５に設けた開口６と略同一面積の異方導電性フィルム７Ａを使用し、該異方導電性フィルム７Ａで開口６を塞いだ状態で、該異方導電性フィルム７Ａ及びカバー絶縁層５の上に接着剤層１２Ｃを設けて、シールド材（金属薄膜）８を該接着剤層１２Ｃを介して異方導電性フィルム７及びカバー絶縁層５に圧着したものである。 The shield wiring circuit board 50 of the fourth example uses an anisotropic conductive film 7A having substantially the same area as the opening 6 provided in the insulating cover layer 5, and the opening 6 is closed with the anisotropic conductive film 7A. Then, an adhesive layer 12C is provided on the anisotropic conductive film 7A and the cover insulating layer 5, and the shield material (metal thin film) 8 is passed through the adhesive layer 12C and the anisotropic conductive film 7 and the cover insulation. The layer 5 is pressure-bonded.

すなわち、シールド材（金属薄膜）８の圧着作業前の異方導電性フィルム７Ａ（図７）は、シールド材８の圧着作業によって圧縮して、図８に示されるように、フィルム基材２０よりも剛性の高い導通路７ａが接着剤層１２Ｃを突き破って貫通して、シールド材（金属薄膜）８に接触することとなり、端子部（パッド）９とシールド材（金属薄膜）８を異方導電性フィルム７Ａ中の導通路７ａを介して確実に導通させることができる。なお、シールド材８の圧着作業における加圧、或いは、加圧及び加熱の条件は、前述の第１例のシールド配線回路基板の条件と同等でよい。 In other words, the anisotropic conductive film 7A (FIG. 7) before the shield material (metal thin film) 8 is crimped is compressed by the crimping operation of the shield material 8, and as shown in FIG. However, the rigid conductive path 7a penetrates through the adhesive layer 12C and comes into contact with the shield material (metal thin film) 8, so that the terminal portion (pad) 9 and the shield material (metal thin film) 8 are anisotropically conductive. Can be reliably conducted through the conduction path 7a in the conductive film 7A. Note that the pressure in the crimping operation of the shield material 8 or the conditions of pressure and heating may be the same as the conditions of the shield wiring circuit board of the first example described above.

接着剤層１２Ｃには、一般的な樹脂及び金属に対して接着性を有する、高耐熱性の接着剤であれば制限なく使用することができ、具体的には、前記接着剤層１２の具体例として挙げた接着剤と同様のものが挙げられる。 The adhesive layer 12C can be used without limitation as long as it is a highly heat-resistant adhesive having adhesiveness to general resins and metals. The thing similar to the adhesive mentioned as an example is mentioned.

接着剤層１２Ｃの厚みは、十分な接着力を得る観点から、一般的には５〜５０μｍ程度であり、好ましくは１０〜２５μｍ程度である。なお、接着剤層１２Ｃはシールド材（金属薄膜）８の片面に予め形成しておくことができる。 The thickness of the adhesive layer 12C is generally about 5 to 50 μm, preferably about 10 to 25 μm, from the viewpoint of obtaining sufficient adhesive force. The adhesive layer 12 C can be formed in advance on one side of the shield material (metal thin film) 8.

カバー絶縁層５に設けた開口６と略同一面積の異方導電性フィルム７Ａを使用する本第４例のシールド配線回路基板５０においても、異方導電性フィルム７Ａは金属細線にて導通路７ａを形成したものが好ましい。 Also in the shielded wiring circuit board 50 of the fourth example using the anisotropic conductive film 7A having substantially the same area as the opening 6 provided in the insulating cover layer 5, the anisotropic conductive film 7A is a conductive path 7a with a thin metal wire. What formed is preferable.

本態様では特に異方導電性フィルム７Ａの厚み（＝導通路７ａの長さ）及び大きさが重要であり、異方導電性フィルム７Ａの厚み（＝導通路７ａの長さ）は、好ましくは１５〜１００μｍであり、より好ましくは２０〜７０μｍである。異方導電性フィルム７Ａの厚み（＝導通路７ａの長さ）が１５μｍ未満の場合、導通路と回路間の導通性及び導通路とシールド材間の導通性が不十分となる恐れがあり、また、異方導電性フィルム７Ａの厚み（＝導通路７ａの長さ）が１００μｍを超えると、接着剤層１２Ｃとカバー絶縁層５との接着を阻害する恐れがあり、好ましくない。 In this embodiment, the thickness of the anisotropic conductive film 7A (= the length of the conductive path 7a) and the size are particularly important, and the thickness of the anisotropic conductive film 7A (= the length of the conductive path 7a) is preferably It is 15-100 micrometers, More preferably, it is 20-70 micrometers. When the thickness of the anisotropic conductive film 7A (= the length of the conduction path 7a) is less than 15 μm, the conduction between the conduction path and the circuit and the conduction between the conduction path and the shield material may be insufficient. On the other hand, if the thickness of the anisotropic conductive film 7A (= the length of the conductive path 7a) exceeds 100 μm, the adhesion between the adhesive layer 12C and the cover insulating layer 5 may be hindered, which is not preferable.

異方導電性フィルム７Ａの大きさは、カバー絶縁層５に設ける開口６と略同一面積に設定する。ここで「開口６と略同一面積」とは、異方導電性フィルム７Ａの平面形状が開口６の形状に対して略相似形の関係にあり、同心に重ねて配置したときに、開口６の輪郭に対して異方導電性フィルム７Ａの外周(周縁）が開口６の輪郭より５０００μｍを超えない範囲で大きい関係である。「開口６の輪郭に対して異方導電性フィルム７Ａの外周(周縁）が大きい」とは、同心（中心点）から開口６の輪郭及び異方導電性フィルム７Ａの外周(周縁）に交わる直線を引いたときに、該直線上の開口６の輪郭との交点から中心点までの距離（Ｘ１）よりも異方導電性フィルム７Ａの外周(周縁）との交点から中心点までの距離(Ｘ２）が大きいことであり、「５０００μｍを超えない範囲で大きい」とは、異方導電性フィルム７Ａの外周(周縁）との交点から中心点までの距離(Ｘ２）と輪郭との交点から中心点までの距離（Ｘ１）との差（Ｘ２−Ｘ１）が５０００μｍ以下であることを意味する。異方導電性フィルムの厚みによっても異なるが、当該寸法差（Ｘ２−Ｘ１）が５０００μｍを超えて大きい場合は、接着層とカバー絶縁層との接着を阻害する傾向となり、かかる寸法差（Ｘ２−Ｘ１）が小さすぎると、開口６上に異方導電性フィルムを配置するのが困難となり、位置合せが困難になる。 The size of the anisotropic conductive film 7 A is set to approximately the same area as the opening 6 provided in the insulating cover layer 5. Here, “substantially the same area as the opening 6” means that the planar shape of the anisotropic conductive film 7 A is substantially similar to the shape of the opening 6, and when the layers are concentrically arranged, The outer periphery (periphery) of the anisotropic conductive film 7A is larger than the contour of the opening 6 in a range not exceeding 5000 μm with respect to the contour. “The outer periphery (periphery) of the anisotropic conductive film 7A is larger than the contour of the opening 6” means that the straight line intersects the contour of the opening 6 and the outer periphery (periphery) of the anisotropic conductive film 7A from the concentricity (center point). , The distance (X2) from the intersection with the outer periphery (periphery) of the anisotropic conductive film 7A to the center point rather than the distance (X1) from the intersection to the center of the opening 6 on the straight line ) Is large, and “large in a range not exceeding 5000 μm” means that the distance from the intersection (X2) to the center point of the outer periphery (periphery) of the anisotropic conductive film 7A and the center point to the center point It means that the difference (X2−X1) from the distance (X1) is 5000 μm or less. Although it differs depending on the thickness of the anisotropic conductive film, when the dimensional difference (X2-X1) is larger than 5000 μm, the adhesion between the adhesive layer and the cover insulating layer tends to be inhibited, and the dimensional difference (X2- If X1) is too small, it becomes difficult to dispose an anisotropic conductive film on the opening 6 and alignment becomes difficult.

また、本第４例のシールド配線回路基板５０においては、シールド材（金属薄膜）８の圧着作業時に異方導電性フィルム７Ａが良好な変形性を示すように、異方導電性フィルム７Ａは−３０〜３００℃での構造物全体としての弾性率が１〜２００００ＭＰａの範囲にあるものが好ましく、１０〜２０００ＭＰａの範囲にあるのものがより好ましい。 Further, in the shielded wiring circuit board 50 of the fourth example, the anisotropic conductive film 7A is − so that the anisotropic conductive film 7A exhibits good deformability when the shield material (metal thin film) 8 is crimped. The elastic modulus as a whole structure at 30 to 300 ° C. is preferably in the range of 1 to 20000 MPa, more preferably in the range of 10 to 2000 MPa.

本第４例のシールド配線回路基板５０では、カバー絶縁層５の開口６と略同一面積にした異方導電性フィルム７Ａを設けた部分を除いてシールド材８／接着剤層１２Ｃ／カバー絶縁層５の積層構造となるので、シールド材が回路基板に対してより安定的に接着して、回路とシールド材とがより一層高い接続信頼性で導通し、また、高温高湿な環境下にさらされても、かかる良好な導通状態が維持される。 In the shielded wiring circuit board 50 of the fourth example, the shield material 8 / adhesive layer 12C / cover insulating layer except for the portion provided with the anisotropic conductive film 7A having substantially the same area as the opening 6 of the cover insulating layer 5. Therefore, the shield material adheres more stably to the circuit board, the circuit and the shield material are conducted with higher connection reliability, and the shield material is exposed to a high temperature and high humidity environment. Even if this is done, such a good conduction state is maintained.

なお、シールド材（金属薄膜）８を接着剤層１２Ｃを用いて回路基板と一体化するので、シールド材（金属薄膜）８には、前記第３例と同様に、金属箔が使用される。金属箔の構成金属は、前記で説明した、銅、クロム、ニッケル、金、銀、白金、パラジウム、チタン、タンタル、はんだ、またはこれらの合金等が好適である。 Since the shield material (metal thin film) 8 is integrated with the circuit board using the adhesive layer 12C, a metal foil is used for the shield material (metal thin film) 8 as in the third example. The constituent metal of the metal foil is preferably copper, chromium, nickel, gold, silver, platinum, palladium, titanium, tantalum, solder, or an alloy thereof described above.

本発明において、上記の第１〜第４例のシールド配線回路基板のように、配線回路基板（基体）１が金属基板付フレキシブル配線回路基板である場合、金属基板２としては、導電性の金属からなる金属箔または金属薄板であって、例えば、ステンレス、銅、アルミニウム、銅−ベリリウム、りん青銅、４２アロイなどが用いられ、ばね性および耐食性を考慮すると、ステンレスが好適である。また、金属基板２の厚さは一般に１０〜６０μｍ、好ましくは１５〜３０μｍ程度である。 In the present invention, when the printed circuit board (base) 1 is a flexible printed circuit board with a metal substrate, like the shielded printed circuit boards in the first to fourth examples, the metal substrate 2 may be a conductive metal. For example, stainless steel, copper, aluminum, copper-beryllium, phosphor bronze, 42 alloy or the like is used, and stainless steel is preferable in consideration of springiness and corrosion resistance. The thickness of the metal substrate 2 is generally about 10 to 60 μm, preferably about 15 to 30 μm.

なお、配線回路基板（基体）が、フレキシブル配線回路基板やリジッド配線回路基板である場合、それらの基材として使用されている通常のフレキシブルフィルム（基板）やリジッド基板上に、上述のベース絶縁層３、回路４、カバー絶縁層５、開口６及び端子部９を設ければよい。 When the printed circuit board (base) is a flexible printed circuit board or a rigid wired circuit board, the above-mentioned base insulating layer is formed on the normal flexible film (board) or rigid board used as the base material. 3, the circuit 4, the insulating cover layer 5, the opening 6, and the terminal portion 9 may be provided.

以下、実施例を示して本発明を具体的に説明する。本発明は以下に記載の実施例に限定されるものではない。
実施例１
（配線回路基板（基体））
下記の材料及び寸法構成の金属基板付フレキシブル配線回路基板を用意した。
金属基板：ステンレス板（厚み：２０μｍ）
ベース絶縁層：ポリイミド（厚み：１５μｍ）
カバー絶縁層：２５μｍ厚のポリイミドフィルムに２５μｍ厚のエポキシ系接着剤層を積層した積層フィルム
開口：平面形状＝正方形、開口径（Ｗ）＝１００μｍ
回路：銅パターン（厚み＝１５μｍ、幅＝３０００μｍ）
端子部：銅導体層上にＮｉバリア層を介してＡｕ表面層を形成した積層構造（厚み＝Ｎｉ層（３μｍ）、Ａｕ層（０．６μｍ））とし、縦１００μｍ×横１００μｍの矩形形状とした。
端子部表面とカバー絶縁層表面の段差（Ｔ）：５０μｍ（端子部の断面観察を行い、測長顕微鏡で測定。） Hereinafter, the present invention will be specifically described with reference to examples. The present invention is not limited to the examples described below.
Example 1
(Wiring circuit board (base))
A flexible printed circuit board with a metal substrate having the following materials and dimensions was prepared.
Metal substrate: Stainless steel plate (thickness: 20 μm)
Base insulating layer: polyimide (thickness: 15 μm)
Cover insulating layer: Laminated film obtained by laminating a 25 μm thick epoxy adhesive layer on a 25 μm thick polyimide film Opening: Planar shape = square, opening diameter (W) = 100 μm
Circuit: Copper pattern (thickness = 15 μm, width = 3000 μm)
Terminal portion: a laminated structure in which an Au surface layer is formed on a copper conductor layer via a Ni barrier layer (thickness = Ni layer (3 μm), Au layer (0.6 μm)), and has a rectangular shape of 100 μm long × 100 μm wide did.
Step (T) between the surface of the terminal portion and the surface of the cover insulating layer: 50 μm (A cross section of the terminal portion is observed and measured with a measuring microscope.)

（異方導電性フィルム）
先ず、外径φ３０μｍの銅線の表面にポリエーテルイミド樹脂によって厚さ約１０μｍの被覆層を形成して外径φ約５０μｍの絶縁導線を形成した。次に、巻線装置を用いて、全長（巻き幅）３００ｍｍ、断面形状３０ｍｍ×３０ｍｍの正方形の角柱状プラスチック芯材に整列巻きを行い線材を最密充填して、１層当たりの平均巻き数６０００ターン、巻き層数２５０層（＝層の厚さ約１２ｍｍ）の巻線コイルを形成した。 (Anisotropic conductive film)
First, a coating layer having a thickness of about 10 μm was formed on the surface of a copper wire having an outer diameter of φ30 μm with a polyetherimide resin to form an insulated conductor having an outer diameter of about 50 μm. Next, using a winding device, an average number of turns per layer is obtained by aligning winding a square prism-shaped plastic core material having a total length (winding width) of 300 mm and a cross-sectional shape of 30 mm × 30 mm and closely packing the wire. A winding coil having 6000 turns and 250 winding layers (= layer thickness of about 12 mm) was formed.

得られたロール状の巻線コイルを、約３００℃に加熱しながら、０．６ｋｇｆ／ｍｍ^２で加圧し、線材が互いに一体化した巻線コイルブロックを得た。この巻線コイルブロックを、巻き付けられた線材と垂直に交わる面（プラスチック芯材の中心軸を含む平面に平行な面）を断面としてシート状にスライスし、縦：約３００ｍｍ×横１２ｍｍ、厚さ１０ｍｍの異方導電性フィルムの前段階のシートを得た。 The obtained rolled coil was heated to about 300 ° C. and pressurized with 0.6 kgf / mm ² to obtain a wound coil block in which the wires were integrated with each other. This winding coil block is sliced into a sheet shape with a plane (plane parallel to the plane including the central axis of the plastic core) perpendicularly intersecting with the wound wire rod, vertical: about 300 mm x width 12 mm, thickness A sheet in the previous stage of a 10 mm anisotropic conductive film was obtained.

次に、得られたシートをさらに薄くスライスし、外径寸法を仕上げて、縦：約４ｍｍ×横約４ｍｍ、厚さ０．０５ｍｍの異方導電性フィルムを得た。導通路（銅線）の配列ピッチは５０μｍであった。次に、導通路の両端部に、酸によるケミカルエッチングを施し、導通路のエッチングにより除去された一方の端部の凹部に、Ｎｉ、Ａｕの順にメッキを行って、２μｍのＮｉ層と、０．１μｍのＡｕ層を順次形成し、凹部を埋め込んだ。 Next, the obtained sheet was further sliced thinly, and the outer diameter was finished to obtain an anisotropic conductive film having a length of about 4 mm × width of about 4 mm and a thickness of 0.05 mm. The arrangement pitch of the conductive paths (copper wires) was 50 μm. Next, both ends of the conductive path are subjected to chemical etching with acid, and the concave portion at one end portion removed by etching of the conductive path is plated in the order of Ni and Au, and a 2 μm Ni layer and 0 A 1 μm Au layer was sequentially formed to fill the recesses.

（シールド配線回路基板）
異方導電性フィルムの導通路のエッチングにより除去された他方の凹部を起点にして、無電解メッキを行って、銅からなる、厚み３μｍの薄膜（シールド材）を異方導電性フィルムの片面に形成した。前述の配線回路基板のカバー絶縁層上に、かかるシールド材が積層された異方導電性フィルムをシールド材とは反対側の面を向けて載置し、この状態で、温度２５０℃、圧力約０．３ｋｇｆ／ｍｍ^２で、約３０秒熱圧着することにより、シールド材が異方導電性フィルムを介して配線回路基板に接着・一体化したシールド配線回路基板を作製した。 (Shield wiring circuit board)
Starting from the other concave portion removed by etching the conduction path of the anisotropic conductive film, electroless plating is performed, and a thin film (shield material) made of copper having a thickness of 3 μm is formed on one side of the anisotropic conductive film. Formed. An anisotropic conductive film in which such a shield material is laminated is placed on the cover insulating layer of the above-described wired circuit board with the surface opposite to the shield material facing, and in this state, the temperature is 250 ° C., the pressure is about A shielded wiring circuit board in which the shield material was bonded and integrated with the wiring circuit board via an anisotropic conductive film was produced by thermocompression bonding at 0.3 kgf / mm ² for about 30 seconds.

実施例２
配線回路基板（基体）におけるカバー絶縁層を１２．５μｍ厚のポリイミドフィルムに１５μｍ厚のエポキシ系接着剤層を積層したものに変更し、開口径（Ｗ）を５００μｍに変更した以外は、実施例１と同様にして、シールド配線回路基板を作製した。 Example 2
Example except that the insulating cover layer of the printed circuit board (base) was changed to a 12.5 μm thick polyimide film laminated with a 15 μm thick epoxy adhesive layer and the opening diameter (W) was changed to 500 μm. In the same manner as in Example 1, a shielded wiring circuit board was produced.

実施例３
配線回路基板（基体）におけるカバー絶縁層を１０μｍ厚の感光性ポリイミドフィルムに変更し、開口径（Ｗ）を２０００μｍに変更した以外は、実施例１と同様にして、シールド配線回路基板を作製した。 Example 3
A shielded wiring circuit board was produced in the same manner as in Example 1 except that the insulating cover layer on the printed circuit board (base) was changed to a 10 μm thick photosensitive polyimide film and the opening diameter (W) was changed to 2000 μm. .

実施例４
配線回路基板（基体）として、実施例２で使用した配線回路基板（基体）と同じものを用意した。
シールド材として、１２．５μｍ厚のポリイミドフィルムに無電解メッキでＣｕ層（厚み：３μｍ）を形成し、その上にエポキシ系接着剤層（厚み：１５μｍ）を形成したものを用意した。
異方導電性フィルムとして、最終のメッキ工程で、導通路の両端部（凹部）にＮｉ／Ａｕ層を形成し、それ以外は実施例１で用いた異方導電性フィルムと同様にして作製した異方導電性フィルムを用意した。
配線回路基板（基体）の開口部の上に異方導電性フィルムを配置し、その上にシールド材をエポキシ系接着剤層側を配線回路基板側に向けて積層し、温度１５０℃、圧力約０．３ｋｇｆ／ｍｍ^２で約３０秒熱圧着（第１作業）後、さらに温度２５０℃、圧力約０．３ｋｇｆ／ｍｍ^２で約３０秒熱圧着（第２作業）を行った。すなわち、第１作業によりシールド材を配線回路基板に接着させ（このとき異方導電性フィルムの導通路が接着剤層を貫通してＣｕ層に接触が同時になされる。）、第２作業で異方導電性フィルムを端子部に接着させた。
その後、１５０℃で熱処理（アフターキュア）を行い、シールド配線回路基板を完成させた。 Example 4
As the printed circuit board (base), the same printed circuit board (base) as used in Example 2 was prepared.
As a shielding material, a 12.5 μm-thick polyimide film having a Cu layer (thickness: 3 μm) formed by electroless plating and an epoxy adhesive layer (thickness: 15 μm) formed thereon was prepared.
As the anisotropic conductive film, Ni / Au layers were formed on both ends (recesses) of the conduction path in the final plating step, and the other was produced in the same manner as the anisotropic conductive film used in Example 1. An anisotropic conductive film was prepared.
An anisotropic conductive film is placed on the opening of the printed circuit board (base), and a shield material is laminated thereon with the epoxy adhesive layer side facing the wired circuit board, at a temperature of 150 ° C. and a pressure of about after 0.3 kgf / mm ² to about 30 seconds thermocompression (first working), was carried out further temperature 250 ° C., for about 30 seconds thermal compression at a pressure of about 0.3 kgf / mm ² (second work). That is, the shield material is adhered to the printed circuit board by the first operation (at this time, the conduction path of the anisotropic conductive film penetrates the adhesive layer and contacts the Cu layer at the same time), and the second operation is different. A directionally conductive film was adhered to the terminal portion.
Thereafter, heat treatment (after cure) was performed at 150 ° C. to complete a shielded wiring circuit board.

比較例１〜３
実施例１〜３のそれぞれにおいて、シールド材を積層した異方導電性フィルムの代わりに、予め片面に導電性接着剤層が形成されている市販のシールド材（タツタシステムエレクトロニクス社製、ＳＦ−ＰＣ５０００）を使用し、圧着条件を、温度１６０℃、圧力約０．３ｋｇｆ／ｍｍ^２とし、その他は同様にして、シールド配線回路基板を作製した。こうして作製された実施例１に対応するものを比較例１、実施例２に対応するものを比較例２、実施例３に対応するものを比較例３とした。 Comparative Examples 1-3
In each of Examples 1 to 3, a commercially available shield material (SF-PC5000, manufactured by Tatsuta System Electronics Co., Ltd.) having a conductive adhesive layer formed on one side in advance instead of the anisotropic conductive film in which the shield material is laminated. ), The pressure bonding conditions were set to a temperature of 160 ° C., a pressure of about 0.3 kgf / mm ² , and the others were similarly fabricated to produce a shielded wiring circuit board. The device corresponding to Example 1 thus produced was designated as Comparative Example 1, the material corresponding to Example 2 was designated as Comparative Example 2, and the material corresponding to Example 3 was designated as Comparative Example 3.

[評価]
貼り合せ（初期）に、配線回路基板のグランドとシールド間の導通が得られたものは、実施例１〜４と比較例２、３で、比較例１は導通しなかった。 [Evaluation]
Examples in which electrical connection between the ground and the shield of the printed circuit board was obtained in pasting (initial stage) were Examples 1 to 4 and Comparative Examples 2 and 3, and Comparative Example 1 was not conductive.

[環境試験]
配線回路基板にシールド材を貼り合せたサンプル（比較例１を除く）を、８５℃、８５％ＲＨに放置した。１０００時間後、抵抗変化率が１０％以下であったのは実施例１〜４で、比較例２、３は全て断線した。なお、実施例４の抵抗変化率は０．５％以下で極めて小さく、実施例１〜３の抵抗変化率（１〜２％以下）に比べてより小さかった。 [Environmental testing]
Samples (excluding Comparative Example 1) in which a shield material was bonded to a printed circuit board were left at 85 ° C. and 85% RH. After 1000 hours, the rate of change in resistance was 10% or less in Examples 1 to 4, and Comparative Examples 2 and 3 were all disconnected. In addition, the resistance change rate of Example 4 was very small at 0.5% or less, and was smaller than the resistance change rate of Examples 1 to 3 (1 to 2% or less).

本発明の第１例のシールド配線回路基板の模式断面図（図（Ａ））と要部拡大図（図（Ｂ））である。It is a schematic cross section (figure (A)) and the principal part enlarged view (figure (B)) of the shield wiring circuit board of the 1st example of this invention. 本発明で使用する異方導電性フィルムの一例の平面図（図（Ａ））と断面図（図（Ｂ））である。It is a top view (figure (A)) and a sectional view (figure (B)) of an example of an anisotropic conductive film used by the present invention. 本発明で使用する異方導電性フィルムの他の例の平面図（図（Ａ））と断面図（図（Ｂ））である。It is a top view (Drawing (A)) and a sectional view (Drawing (B)) of other examples of an anisotropic conductive film used by the present invention. 本発明で使用する異方導電性フィルムにおける導通路の好適態様を示す図である。It is a figure which shows the suitable aspect of the conduction path in the anisotropic conductive film used by this invention. 本発明の第２例のシールド配線回路基板の要部の模式断面図である。It is a schematic cross section of the principal part of the shield wiring circuit board of the 2nd example of the present invention. 本発明の第３例のシールド配線回路基板の要部の模式断面図である。It is a schematic cross section of the principal part of the shield wiring circuit board of the 3rd example of the present invention. 本発明の第４例のシールド配線回路基板の要部の模式断面図（シールド材の圧着前）である。It is a schematic cross section (before crimping | bonding of a shielding material) of the principal part of the shield wiring circuit board of the 4th example of this invention. 本発明の第４例のシールド配線回路基板の要部の模式断面図（シールド材の圧着後）である。It is a schematic cross section (after crimping | bonding of a shielding material) of the principal part of the shield wiring circuit board of the 4th example of this invention.

Explanation of symbols

１配線回路基板（基体）
２金属基板
３ベース絶縁層
４回路
５カバー絶縁層
６開口
７異方導電性フィルム
７ａ導通路
８シールド材（金属薄膜）
９端子部
１０、３０、４０、５０シールド配線回路基板
１２、１２Ａ、１２Ｂ、１２Ｃ接着剤層 1 Printed circuit board (base)
2 Metal substrate 3 Base insulating layer 4 Circuit 5 Cover insulating layer 6 Opening 7 Anisotropic conductive film 7a Conducting path 8 Shield material (metal thin film)
9 Terminal part 10, 30, 40, 50 Shield wiring circuit board 12, 12A, 12B, 12C Adhesive layer

Claims

A circuit and a cover insulating layer covering the circuit are formed on the base insulating layer;
An opening is formed in the insulating cover layer;
A terminal part is formed on the circuit exposed at the bottom of the opening;
On the cover insulating layer, an anisotropic conductive film in which a shield material is integrally provided on one side is laminated with one side opposite to the one side facing the cover insulating layer,
The anisotropic conductive film is a structure provided with a plurality of conduction paths penetrating in the thickness direction of the base material in a film base material made of an insulating material,
The anisotropic conductive film adheres to the cover insulating layer and the terminal portion,
The shield wiring circuit board, wherein the terminal portion and the shield material are conducted through a conduction path in the anisotropic conductive film.

The insulating cover layer and the anisotropic conductive film are bonded via an adhesive layer, and a conduction path in the anisotropic conductive film passes through the adhesive layer and contacts the terminal portion. The shielded wiring circuit board described.

The shield material is bonded to one side of the anisotropic conductive film via an adhesive layer, and a conduction path in the anisotropic conductive film passes through the adhesive layer and is in contact with the shield material. 3. A shielded wiring circuit board according to 1 or 2.

A circuit and a cover insulating layer covering the circuit are formed on the base insulating layer;
An opening is formed in the insulating cover layer;
A terminal part is formed on the circuit exposed at the bottom of the opening;
An anisotropic conductive film having substantially the same area as the opening is disposed on the terminal portion,
A shielding material is disposed on the anisotropic conductive film and the cover insulating layer,
The anisotropic conductive film is a structure provided with a plurality of conduction paths penetrating in the thickness direction of the base material in a film base material made of an insulating material,
The shield material is bonded onto the anisotropic conductive film and the cover insulating layer via an adhesive layer,
The shield wiring circuit board, wherein the terminal portion and the shield material are electrically connected by a conduction path in the anisotropic conductive film penetrating the adhesive layer.

The shield wired circuit board according to any one of claims 1 to 4, wherein the cover insulating layer has a thickness of 10 to 50 µm and an opening diameter (W) of 100 to 2000 µm.

The shield wiring circuit board according to any one of claims 1 to 5, wherein the conduction path of the anisotropic conductive film is formed of a thin metal wire.

The shield wiring circuit board according to claim 1, wherein the surface of the terminal portion is an Au film or an Sn film.