JP2004247668A

JP2004247668A - Lamination forming mid wiring member, wiring board, and their manufacturing method

Info

Publication number: JP2004247668A
Application number: JP2003038223A
Authority: JP
Inventors: Osamu Shimada; 修嶋田; Kazuhisa Suzuki; 和久鈴木; Ryoji Kawasaki; 良次川崎; Mitsuo Kikuchi; 滿男菊地
Original assignee: Hitachi Chemical Co Ltd
Current assignee: Showa Denko Materials Co Ltd
Priority date: 2003-02-17
Filing date: 2003-02-17
Publication date: 2004-09-02
Anticipated expiration: 2023-02-17
Also published as: JP4337358B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a structure which improves reliability of the interlayer connection in an interlayer connection member wherein a resin to be a base material is filled in after conductive projections are formed on a metal foil, and also to provide its manufacturing method. <P>SOLUTION: (1) A wiring member has a conductor layer and a plurality of conductive projections projecting from one surface of the conductor layer. (2) A conductive resin is applied onto the top faces of the conductive projections of the wiring member. (3) In a lamination forming mid wiring member A including an insulating resin which buries the conductive projections and the conductive resin therein while exposing the top faces of the conductive resin on the surface side having the conductive projections of the wiring member, the conductive resin and the insulating resin are in a semi-cured state, and the surface of the insulating resin and the exposed faces of the conductive resin exposed from the surface of the insulating resin form an evenly flattened surface. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、積層用中間配線部材とその製造方法、配線板及び半導体パッケージ用基板とそれらの製造方法、並びに、多層配線板及び半導体パッケージ用多層基板とそれらの製造方法に関する。
【０００２】
【従来の技術】
近年の電子部品の高密度実装化に伴い、配線板の配線密度の向上が求められるようになってきている。また、配線板に搭載する半導体パッケージにおいても同様の要求が高まっている。一般に半導体パッケージの場合、入出力端子をパッケージの周辺に一列配置するタイプと、周辺だけでなく内部まで多列に配置するタイプがある。前者は、ＱＦＰ（ＱｕａｄＦｌａｔＰａｃｋａｇｅ）が代表的である。これを多端子化する場合は、端子ピッチを縮小することが必要であるが、０．５ｍｍピッチ以下の領域では、配線板との接続に高度な技術が必要になる。後者のアレイタイプは比較的大きなピッチで端子配列が可能なため、多ピン化に適している。従来、アレイタイプは接続ピンを有するＰＧＡ（ＰｉｎＧｒｉｄＡｒｒａｙ）が一般的であるが、配線板との接続は挿入型となり、表面実装には適していない。このため、表面実装可能なＢＧＡ（ＢａｌｌＧｒｉｄＡｒｒａｙ）と称するパッケージが開発されている。
【０００３】
一方、電子機器の小型化に伴って、パッケージサイズの更なる小型化の要求が強くなってきた。この小型化に対応するものとして、半導体チップとほぼ同等サイズの、いわゆるチップサイズパッケージ（ＣＳＰ；ＣｈｉｐＳｉｚｅＰａｃｋａｇｅ）が提案されている。これは、半導体チップの周辺部でなく、実装領域内に外部配線基板との接続部即ち外部接続端子を有するパッケージである。具体例としては、バンプ付きポリイミドフィルムを半導体チップの表面に接着し、チップと金リード線により電気的接続を図った後、エポキシ樹脂などをポッティングして封止したもの（例えば、非特許文献１を参照）や、仮基板上に半導体チップ及び外部配線基板との接続部に相当する位置に金属バンプを形成し、半導体チップをフェースダウンボンディング後、仮基板上でトランスファーモールドしたもの（例えば、非特許文献２を参照）などがある。
【０００４】
これらの半導体パッケージは、何れも、接続端子と半導体チップとの接続のために、スルーホール、バイアホールを用いている。スルーホール、バイアホールは基材の接続端子となる箇所に予めドリルやレーザなどで穴を設け、はんだや導電ペーストを充填したり、スルーホールめっき、穴埋めめっきなどをして接続端子を設ける方法が一般的であるが、この方法では穴の小径化に限界があり、多ピン化になるほどコストＵＰとなる。
そこで、予め金属箔上に導電性突起をめっき法又は印刷法又はエッチング法によって設けておき、後から基材となる樹脂を埋め込んだのち又は同時に、金属箔又は配線部材を接続する方法が提案されている。これらの工法において接続信頼性を向上するために導電性突起頭部に導電性樹脂や金めっき、はんだめっき等を施す方法も提案されている。また、本発明者らは、金属箔をエッチングして形成したバンプを樹脂で埋め込み、層間接続用の配線に利用した半導体パッケージを開発した（例えば、特許文献１を参照）。これに使用されるパッケージ基板の樹脂を、半硬化状態（Ｂステージ状態）にすれば、この基板の導電性突起面と金属箔又は配線部材とを合わせて加圧・加熱処理することで容易に層間接続された配線部材を製造することが出来る。しかしながら、この方法では導電性突起と金属箔又は配線部材との接続はただ突き当てられているだけで周りの樹脂の接着力で接続が保たれているため長期信頼性に不安がある。信頼性を向上するために導電性樹脂を絶縁樹脂から露出した状態の導電性突起頭部に塗布した後、接続する方法もあるが接合面に凹凸が出来るため、密着が不均一になったり、張りは合わせた状態での平坦度が悪くなったりする。これらを改善するには加熱加圧時に流動性が高い樹脂を使う必要があり樹脂の選択に大きな制約が出てくる。また流動性が高いと、ズレやすく厚みも不均一になりやすい。
【０００５】
【非特許文献１】
ＮＩＫＫＥＩＭＡＴＥＲＩＡＬＳ＆ＴＥＣＨＮＯＬＯＧＹ９４．４，Ｎｏ．１４０，ｐ１８−１９
【非特許文献２】
ＳｍａｌｌｅｓｔＦｌｉｐ−Ｃｈｉｐ−ＬｉｋｅＰａｃｋａｇｅＣＳＰ；ＴｈｅＳｅｃｏｎｄＶＬＳＩＰａｃｋａｇｉｎｇＷｏｒｋｓｈｏｐｏｆＪａｐａｎ，ｐ４６−５０，１９９４
【特許文献１】
特開２００２−０４３４６７号公報
【０００６】
【発明が解決しようとする課題】
予め金属箔上に導電性突起を形成し、後から基材となる樹脂を埋め込む層間接続部材において、本発明は層間接続の信頼性を向上させる構造及び製造方法を提供することを目的とする。
【０００７】
【課題を解決するための手段】
上記の問題を解決するために、本発明者らは、導電性突起頭部に導電性樹脂を塗布した状態で樹脂に埋め込まれた状態であって、絶縁樹脂表面にほとんど導電性樹脂が出ていない状態でかつほとんど凹んでもいない状態の層間接続部材とその製造法を考案した。
【０００８】
すなわち、本発明は、下記の積層用中間配線部材、それを用いた配線板、及びそれらの製造方法を提供するものである。
（１）（１）導電体層及び導電体層の片面に突出する複数の導電性突起を有する配線部材、（２）配線部材の導電性突起の先端面上に塗布された導電性樹脂、及び、（３）配線部材の導電性突起を有する面側で、導電性樹脂の先端面を露出させて導電性突起及び導電性樹脂を埋め込んでいる絶縁樹脂を有する積層用中間配線部材であって、導電性樹脂及び絶縁樹脂が、流動性はないが完全な硬化状態に至る前の半硬化状態にあり、絶縁樹脂表面と絶縁樹脂表面に露出した導電性樹脂の露出面が、平坦な平坦化面を形成している積層用中間配線部材Ａ。
（２）配線部材が、導電体層が少なくとも第３金属の層からなり、導電性突起が導電体層上の第２金属の層と第２金属の層上の第１金属の層の２層からなるもの、又は、配線部材が、導電体層が少なくとも第３金属の層と、第３金属の層上の第２金属の層とからなり、導電性突起が導電体層の第２金属の層上の第１金属からなるものである（１）に記載の積層用中間配線部材Ａ。
【０００９】
（３）第１金属と第２金属とが、互いにエッチング条件の異なる金属であり、第２金属と第３金属とが、互いにエッチング条件の異なる金属である（２）に記載の積層用中間配線部材Ａ。
（４）絶縁樹脂が、導電体層に接する第１絶縁樹脂からなるコア層と、導電体層上の第２絶縁樹脂からなる表面層との少なくとも２層からなり、半硬化状態にある第１絶縁樹脂が、半硬化状態にある第２絶縁樹脂よりも固いものである（１）〜（３）のいずれかに記載の積層用中間配線部材Ａ。
（５）絶縁樹脂表面に露出した導電性樹脂の露出面の面積が、導電性突起の先端面の面積より小さい（１）〜（４）のいずれかに記載の積層用中間配線部材Ａ。
【００１０】
（６）（１）導電体層及び導電体層の片面に突出する複数の導電性突起を有する配線部材、（２）配線部材の導電性突起を有する面側で、導電性突起を埋め込んでいる絶縁樹脂であって、表面が導電性突起の先端面を底とする凹部を有する以外は平坦化された平坦化絶縁樹脂面を形成している絶縁樹脂、及び、（３）導電性突起の先端面上に塗布された導電性樹脂を有する積層用中間配線部材であって、導電性樹脂及び絶縁樹脂が、流動性はないが完全な硬化状態に至る前の半硬化状態にある積層用中間配線部材Ｂ。
（７）配線部材が、導電体層が第３金属からなり、導電性突起が導電体層上の第２金属の層と第２金属の層上の第１金属の層の２層からなるもの、又は、配線部材が、導電体層が第３金属の層と、第３金属の層上の第２金属の層とからなり、導電性突起が導電体層の第２金属の層上の第１金属からなるものである（６）に記載の積層用中間配線部材Ｂ。
【００１１】
（８）第１金属と第２金属とが、互いにエッチング条件の異なる金属であり、第２金属と第３金属とが、互いにエッチング条件の異なる金属である（７）に記載の積層用中間配線部材Ｂ。
（９）絶縁樹脂が、導電体層に接する第１絶縁樹脂からなるコア層と、導電体層上の第２絶縁樹脂からなる表面層との少なくとも２層からなり、半硬化状態にある第１絶縁樹脂が、半硬化状態にある第２絶縁樹脂よりも固いものである（６）〜（８）のいずれかに記載の積層用中間配線部材Ｂ。
【００１２】
（１０）（１）〜（５）のいずれかに記載の積層用中間配線部材Ａの平坦化面上に又は（６）〜（９）のいずれかに記載の積層用中間配線部材Ｂの平坦絶縁樹脂面上に、加熱加圧によって接着した導電体回路を形成し、半硬化状態の絶縁樹脂及び半硬化状態の導電性樹脂を硬化させ、導電体層を部分エッチングにより回路形成することにより得られる配線板。
（１１）半導体パッケージ用基板として用いられる（１０）に記載の配線板。
【００１３】
（１２）導電体層及び導電体層の片面に突出する複数の導電性突起を有する配線部材の導電性突起の先端面に導電性樹脂を塗布する導電性樹脂塗布工程、塗布した導電性樹脂を流動性はなくなるが完全な硬化状態に至る前の、半硬化状態まで乾燥する導電性樹脂乾燥工程、硬化前の流動状のワニス状態にある絶縁樹脂を、配線部材の導電性突起を有する面上に、印刷により、導電性突起及び半硬化状態の導電性樹脂が絶縁樹脂に埋め込まれる厚みに塗布する絶縁樹脂印刷工程、印刷した絶縁樹脂を流動性はなくなるが完全な硬化状態に至る前の、半硬化状態まで乾燥する絶縁樹脂乾燥工程、及び、半硬化状態の絶縁樹脂を研磨し、半硬化状態の導電性樹脂を露出させ、かつ、導電性樹脂の露出面を含む絶縁樹脂の表面を平坦化する研磨工程を有する（１）に記載の積層用中間配線部材Ａの製造方法。
（１３）配線部材を、第１金属からなる第１金属層、第２金属からなる第２金属層及び第３金属からなる第３金属層の少なくとも３層をこの順で有する多層金属箔を用い、第１金属層を部分的に第２金属層が露出するまで除去することにより、第２金属層及び第３金属層からなる導電体層及び第１金属からなる複数の導電性突起を形成することにより作製するか、又は、該多層金属箔を用い、第１金属層及び第２金属層を部分的に第３金属層が露出するまで除去すること陰より、第３金属層からなる導電体層及び第２金属の層と第２金属の層上の第３金属の層とからなる複数の導電性突起を形成することにより作製する（１２）に記載の積層用中間配線部材Ａの製造方法。
【００１４】
（１４）第１金属と第２金属とが、互いにエッチング条件の異なる金属であり、第２金属と第３金属とが、互いにエッチング条件の異なる金属であり、第１金属層の部分的な除去をエッチングにより行なうか、又は、第１金属層及び第２金属層の部分的な除去を、互いに異なるエッチング条件下で順次エッチングして行なう（１４）に記載の積層用中間配線部材Ａの製造方法。
（１５）絶縁樹脂印刷工程において、絶縁樹脂として第１絶縁樹脂及び第２絶縁樹脂の少なくとも２種類の絶縁樹脂を用い、第１絶縁樹脂を導電体層上に印刷してコア層を形成し、その後第２絶縁樹脂を印刷して表面層を形成し、半硬化状態にある第１絶縁樹脂が、半硬化状態にある第２絶縁樹脂よりも固いものである（１２）〜（１４）のいずれかに記載の積層用中間配線部材Ａの製造方法。
【００１５】
（１６）導電体層及び導電体層の片面に突出する複数の導電性突起を有する配線部材の、導電性突起を有する面上に、硬化前の流動状のワニス状態にある絶縁樹脂を、印刷により、導電性突起が絶縁樹脂に埋め込まれる厚みに塗布する絶縁樹脂印刷工程、印刷した絶縁樹脂を流動性はなくなるが完全な硬化状態に至る前の、半硬化状態まで乾燥する絶縁樹脂乾燥工程、半硬化状態の絶縁樹脂を研磨することにより、導電性突起の先端面を露出させ、かつ、半硬化状態の絶縁樹脂表面を平坦化して平坦化絶縁樹脂面を形成する研磨工程、露出した導電性突起を露出した先端面からエッチングしてハーフエッチングするハーフエッチング工程、ハーフエッチングされた導電性突起の先端面に導電性樹脂を塗布する導電性樹脂塗布工程、及び、塗布された導電性樹脂を、流動性はなくなるが完全な硬化状態に至る前の、半硬化状態まで乾燥する導電性樹脂乾燥工程を有する（６）に記載の積層用中間配線部材Ｂの製造方法。
【００１６】
（１７）配線部材を、第１金属からなる第１金属層、第２金属からなる第２金属層及び第３金属からなる第３金属層の少なくとも３層をこの順で有する多層金属箔を用い、第１金属層を部分的に第２金属層が露出するまで除去することにより、第２金属層及び第３金属層からなる導電体層及び第１金属からなる複数の導電性突起を形成することにより作製するか、又は、該多層金属箔を用い、第１金属層及び第２金属層を部分的に第３金属層が露出するまで除去することにより、第３金属層からなる導電体層及び第２金属の層と第２金属の層上の第１金属の層とからなる複数の導電性突起を形成することにより作製する（１６）に記載の積層用中間配線部材Ｂの製造方法。
（１８）第１金属と第２金属とが、互いにエッチング条件の異なる金属であり、第２金属と第３金属とが、互いにエッチング条件の異なる金属であり、第１金属層の部分的な除去をエッチングにより行なうか、又は、第１金属層及び第２金属層の部分的な除去を、互いに異なるエッチング条件下で順次エッチングして行なう（１７）に記載の積層用中間配線部材Ｂの製造方法。
【００１７】
（１９）絶縁樹脂印刷工程において、絶縁樹脂として第１絶縁樹脂及び第２絶縁樹脂の少なくとも２種類の絶縁樹脂を用い、第１絶縁樹脂を導電体層上に印刷してコア層を形成し、その後第２絶縁樹脂を印刷して表面層を形成し、半硬化状態にある第１絶縁樹脂が、半硬化状態にある第２絶縁樹脂よりも固いものである（１６）〜（１８）のいずれかに記載の積層用中間配線部材Ｂの製造方法。
（２０）（１）〜（５）のいずれかに記載の積層用中間配線部材Ａの平坦化面上に又は（６）〜（９）のいずれかに記載の積層用中間配線部材Ｂの平坦化絶縁樹脂面上に、加熱加圧によって接着した導電体回路を形成し、半硬化状態の絶縁樹脂及び半硬化状態の導電性樹脂を硬化させ、導電体層を部分エッチングにより回路形成することを含む配線板の製造方法。
（２１）配線板が半導体パッケージ用基板である（２０）に記載の配線板の製造方法。
【００１８】
（２２）（１）〜（５）のいずれかに記載の積層用中間配線部材Ａの平坦化面上に、金属箔を戴置し、圧力及び熱を加えることで金属箔と積層用中間配線部材Ａとを接着しかつ半硬化状態の絶縁樹脂及び半硬化状態の導電性樹脂を硬化する工程と、積層用中間配線部材Ａの導電体層と接着した金属箔とを各々部分エッチングにより回路形成する工程を有する配線板の製造方法。
（２３）配線板が半導体パッケージ用基板である（２２）に記載の配線板の製造方法。
（２４）（６）〜（９）のいずれかに記載の積層用中間配線部材Ｂの平坦化絶縁樹脂面上に、金属箔を戴置し、圧力及び熱を加えることで金属箔と積層用中間配線部材Ｂとを接着しかつ半硬化状態の絶縁樹脂及び半硬化状態の導電性樹脂を硬化する工程と、積層用中間配線部材Ｂの導電体層と接着した金属箔とを各々部分エッチングにより回路形成する工程を有する配線板の製造方法。
（２５）配線板が半導体パッケージ用基板である（２４）に記載の配線板の製造方法。
【００１９】
（２６）（１）〜（５）のいずれかに記載の積層用中間配線部材Ａの平坦化面に、金属箔を戴置し圧力及び熱を加えることで金属箔と積層用中間配線部材Ａとを接着しかつ半硬化状態の絶縁樹脂及び半硬化状態の導電性樹脂を硬化する工程、積層用中間配線部材Ａの導電体層及び／又は接着した金属箔を部分エッチングして回路形成して配線部材Ｃを作製する工程、別の（１）〜（５）のいずれかに記載の積層用中間配線部材Ａ′と配線部材Ｃとを、積層用中間配線部材Ａ′の平坦化面と配線部材Ｃの回路とが接触するように積層し、圧力及び熱を加えることで配線部材Ｃと積層用中間配線部材Ａ′とを接着しかつ積層用中間配線部材Ａ′の半硬化状態の絶縁樹脂及び半硬化状態の導電性樹脂を硬化する工程、積層用中間配線部材Ａ′の導電体層と、接着した配線部材Ｃの回路形成されていない導電体層又は金属箔とを、部分エッチングにより回路形成する工程を有する多層配線板の製造方法。
（２７）多層配線板が半導体パッケージ用多層基板である（２６）に記載の製造方法。
【００２０】
（２８）（６）〜（９）のいずれかに記載の積層用中間配線部材Ｂの平坦化絶縁樹脂面に、金属箔を戴置し圧力及び熱を加えることで金属箔と積層用中間配線部材Ｂとを接着しかつ半硬化状態の絶縁樹脂及び半硬化状態の導電性樹脂を硬化する工程、積層用中間配線部材Ｂの導電体層及び／又は接着した金属箔を部分エッチングして回路形成して配線部材Ｄを作製する工程、別の（６）〜（９）のいずれかに記載の積層用中間配線部材Ｂ′と配線部材Ｄとを、積層用中間配線部材Ｂ′の平坦化絶縁樹脂面と配線部材Ｄの回路とが接触するように積層し、圧力及び熱を加えることで配線部材Ｄと積層用中間配線部材Ｂ′とを接着しかつ積層用中間配線部材Ｂ′の半硬化状態の絶縁樹脂及び半硬化状態の導電性樹脂を硬化する工程、積層用中間配線部材Ｂ′の導電体層と、接着した配線部材Ｄの回路形成されていない導電体層又は金属箔とを、部分エッチングにより回路形成する工程を有する多層配線板の製造方法。
（２９）多層配線板が半導体パッケージ用多層基板である（２８）に記載の製造方法。
【００２１】
（３０）第１金属からなる第１金属層、第２金属からなる第２金属層及び第３金属からなる第３金属層の少なくとも３層をこの順で有し、第１金属と第２金属とが互いにエッチング条件の異なる金属であり、第２金属と第３金属とが互いにエッチング条件の異なる金属である多層金属箔を用意し、第１金属層を第２金属層が露出するまで部分的にエッチングすることにより、第２金属層の露出面上に第１金属からなる複数の導電性突起を形成し、あるいは、第１金属層及び第２金属層をこの順で第３金属層が露出するまで各々部分的にエッチングすることにより、第３金属層の露出面上に第１金属の層及び第２金属の層の２層からなる複数の導電性突起を形成する導電性突起形成工程、第２金属層の露出面上又は第３金属層の露出面上に、硬化前の流動状のワニス状態にある絶縁樹脂を、印刷により、導電性突起が絶縁樹脂に埋め込まれる厚みに塗布する印刷工程、印刷した絶縁樹脂を、半硬化状態に乾燥又は又は完全な硬化状態に乾燥又は硬化させる乾燥又は硬化工程、半硬化状態又は硬化した絶縁樹脂を研磨することにより、絶縁樹脂表面に導電性突起の先端面を露出させ、かつ絶縁樹脂表面を平坦化する研磨工程、エッチングされていない第２金属層及び第３金属層又はエッチングされていない第３金属層を部分エッチングして回路を形成することにより回路面を形成して配線部材Ｅを作製する工程、配線部材Ｅと（１）〜（５）のいずれかに記載の積層用中間配線部材Ａとを、配線部材Ｅの回路面と積層用中間配線部材Ａの平坦化面とが接するように積層し、圧力及び熱を加えることで配線部材Ｅと積層用中間配線部材Ａとを接着しかつ半硬化状態の絶縁樹脂及び半硬化状態の導電性樹脂を硬化する工程、及び、積層用中間配線部材Ａの導電体層を部分エッチングして回路形成する工程を有する多層配線板の製造方法。
（３１）多層配線板が半導体パッケージ用多層基板である（３０）に記載の製造方法。
【００２２】
（３２）第１金属からなる第１金属層、第２金属からなる第２金属層及び第３金属からなる第３金属層の少なくとも３層をこの順で有し、第１金属と第２金属とが互いにエッチング条件の異なる金属であり、第２金属と第３金属とが互いにエッチング条件の異なる金属である多層金属箔を用意し、第１金属層を第２金属層が露出するまで部分的にエッチングすることにより、第２金属層の露出面上に第１金属からなる複数の導電性突起を形成し、あるいは、第１金属層及び第２金属層をこの順で第３金属層が露出するまで各々部分的にエッチングすることにより、第３金属層の露出面上に第１金属の層及び第２金属の層の２層からなる複数の導電性突起を形成する導電性突起形成工程、第２金属層の露出面上又は第３金属層の露出面上に、硬化前の流動状のワニス状態にある絶縁樹脂を、印刷により、導電性突起が絶縁樹脂に埋め込まれる厚みに塗布する印刷工程、印刷した絶縁樹脂を、半硬化状態に乾燥又は又は完全な硬化状態に乾燥又は硬化させる乾燥又は硬化工程、半硬化状態又は硬化した絶縁樹脂を研磨することにより、絶縁樹脂表面に導電性突起の先端面を露出させ、かつ絶縁樹脂表面を平坦化する研磨工程、エッチングされていない第２金属層及び第３金属層又はエッチングされていない第３金属層を部分エッチングして回路を形成することにより回路面を形成して配線部材Ｅを作製する工程、配線部材Ｅと（６）〜（９）のいずれかに記載の積層用中間配線部材Ｂとを、配線部材Ｅの回路面と積層用中間配線部材Ｂの平坦化絶縁樹脂面とが接するように積層し、圧力及び熱を加えることで配線部材Ｅと積層用中間配線部材Ｂとを接着しかつ半硬化状態の絶縁樹脂及び半硬化状態の導電性樹脂を硬化する工程、及び、積層用中間配線部材Ｂの導電体層を部分エッチングして回路形成する工程を有する多層配線板の製造方法。
（３３）多層配線板が半導体パッケージ用多層基板である（３２）に記載の製造方法。
【００２３】
（３４）（１）〜（５）のいずれかに記載の積層用中間配線部材Ａの平坦化面に、導電性樹脂をスクリーン印刷して回路を形成し、流動性はなくなるが完全な硬化状態に至る前の、半硬化状態まで乾燥する工程、積層用中間配線部材Ａと別の（１）〜（５）のいずれかに記載の積層用中間配線部材Ａ′とを、積層用中間配線部材Ａの回路形成した面と積層用中間配線部材Ａ′の平坦化面とが接するように積層し、圧力及び熱を加えることで積層用中間配線部材Ａと積層用中間配線部材Ａ′とを接着しかつ半硬化状態の絶縁樹脂及び半硬化状態の導電性ペーストを硬化する工程、及び、積層用中間配線部材Ａの導電体層と積層用中間配線部材Ａ′の導電体層を部分エッチングして回路形成する工程を有する多層配線板の製造方法。
（３５）多層配線板が半導体パッケージ用多層基板である（３４）に記載の製造方法。
【００２４】
（３６）（６）〜（９）のいずれかに記載の積層用中間配線部材Ｂの平坦化絶縁樹脂面に、導電性樹脂をスクリーン印刷して回路を形成し、流動性はなくなるが完全な硬化状態に至る前の、半硬化状態まで乾燥する工程、積層用中間配線部材Ｂと別の（６）〜（９）のいずれかに記載の積層用中間配線部材Ｂ′とを、積層用中間配線部材Ｂの回路形成した面と積層用中間配線部材Ｂ′の平坦化絶縁樹脂面とが接するように積層し、圧力及び熱を加えることで積層用中間配線部材Ｂと積層用中間配線部材Ｂ′とを接着しかつ半硬化状態の絶縁樹脂及び半硬化状態の導電性ペーストを硬化する工程、及び、積層用中間配線部材Ｂの導電体層と積層用中間配線部材Ｂ′の導電体層を部分エッチングして回路形成する工程を有する多層配線板の製造方法。
（３７）多層配線板が半導体パッケージ用多層基板である（３６）に記載の製造方法。
【００２５】
【発明の実施の形態】
本発明の積層用中間配線部材Ａは、（１）導電体層及び導電体層の片面に突出する複数の導電性突起を有する配線部材、（２）配線部材の導電性突起の先端面上に塗布された導電性樹脂、及び、（３）配線部材の導電性突起を有する面側で、導電性樹脂の先端面を露出させて導電性突起及び導電性樹脂を埋め込んでいる絶縁樹脂を有するものであり、導電性樹脂及び絶縁樹脂は、流動性はないが完全な硬化状態に至る前の半硬化状態にあり、絶縁樹脂表面と絶縁樹脂表面に露出した導電性樹脂の露出面が、平坦な平坦化面を形成している。
【００２６】
また、本発明の積層用中間配線部材Ｂは、（１）導電体層及び導電体層の片面に突出する複数の導電性突起を有する配線部材、（２）配線部材の導電性突起を有する面側で、導電性突起を埋め込んでいる絶縁樹脂であって、表面が導電性突起の先端面を底とする凹部を有する以外は平坦化された平坦化絶縁樹脂面を形成している絶縁樹脂、及び、（３）導電性突起の先端面上に塗布された導電性樹脂を有するものであり、導電性樹脂及び絶縁樹脂は、流動性はないが完全な硬化状態に至る前の半硬化状態にある。導電性樹脂は、平坦化絶縁樹脂面の凹部において、導電性突起の先端面上に塗布されている。積層用中間配線部材Ｂにおいては、絶縁樹脂の表面が凹部を除いて平坦化されていればよく、導電性樹脂の上面は、必ずしも、絶縁樹脂平坦化面の平坦部分と同一平面上になくてもよい。また、導電性樹脂は、必ずしも絶縁樹脂で先端面を除いて完全に埋め込まれていなくてもよい。ただし、各凹部において塗布されている導電性樹脂の量は、凹部の容積と同量又はほぼ同量であることが好ましく、通常、凹部の容積の８０〜１３０容量％であることが好ましい。
【００２７】
積層用中間配線部材Ａ及びＢの絶縁樹脂及び導電性樹脂が半硬化状態であり、また表面が平坦又はほとんど平坦である。従って、平坦化面又は平坦化絶縁樹脂面上に金属箔や他の配線部材積層する場合、加熱・加圧処理によって、容易に均一かつ平坦に密着させることができる。また、導電性突起と金属箔や配線部材とも、単なる突き当てだけでなく、導電性樹脂によって接着される。従って、層間接続の信頼性が、著しく向上する。
本発明において、平坦とは、表面の凹凸が１０μｍ以下、又は、絶縁樹脂の厚みに対して、±１０％以下の平坦性を有していることを言う。
【００２８】
積層用中間配線部材Ａは、例えば、本発明の積層用中間配線部材Ａの製造方法によって好適に製造することができる。まず、導電体層及び導電体層の片面に突出する複数の導電性突起を有する配線部材の導電性突起の先端面に、導電性樹脂を塗布する（導電性樹脂塗布工程）。次いで、導電性突起の先端面に塗布した導電性樹脂を、流動性はなくなるが完全な硬化状態に至る前の半硬化状態まで乾燥する（導電性樹脂乾燥工程）。次いで、硬化前の流動状のワニス状態にある絶縁樹脂を、配線部材の導電性突起を有する面上に、印刷により、導電性突起及び半硬化状態の導電性樹脂が絶縁樹脂に埋め込まれる厚みに塗布する（絶縁樹脂印刷工程）。次いで、印刷した絶縁樹脂を流動性はなくなるが完全な硬化状態に至る前の、半硬化状態まで乾燥する（絶縁樹脂乾燥工程）。その後、半硬化状態の絶縁樹脂を研磨し、半硬化状態の導電性樹脂を露出させ、かつ、導電性樹脂の露出面を含む絶縁樹脂の表面を平坦化する（研磨工程）ことにより、積層用中間配線部材Ａを得る。
【００２９】
積層用中間配線部材Ｂは、例えば、本発明の積層用中間配線部材Ｂの製造方法によって好適に製造することができる。まず、導電体層及び導電体層の片面に突出する複数の導電性突起を有する配線部材の、導電性突起を有する面上に、硬化前の流動状のワニス状態にある絶縁樹脂を、印刷により、導電性突起が絶縁樹脂に埋め込まれる厚みに塗布する（絶縁樹脂印刷工程）。次いで、印刷した絶縁樹脂を、流動性はなくなるが完全な硬化状態に至る前の半硬化状態まで乾燥する（絶縁樹脂乾燥工程）。次いで、半硬化状態の絶縁樹脂を研磨することにより、導電性突起の先端面を露出させ、かつ、半硬化状態の絶縁樹脂表面を平坦化して平坦化絶縁樹脂面を形成する（研磨工程）。次いで、露出した導電性突起を露出した先端面からエッチングしてハーフエッチングする（ハーフエッチング工程）。この工程において、平坦化絶縁樹脂面に、ハーブエッチングされた導電性突起の先端面を底とする凹部が形成される。次いで、ハーフエッチングされた導電性突起の先端面に導電性樹脂を塗布する（導電性樹脂塗布工程）。次いで、塗布された導電性樹脂を、流動性はなくなるが完全な硬化状態に至る前の半硬化状態まで乾燥する（導電性樹脂乾燥工程）ことにより、積層用中間配線部材Ｂを得る。
【００３０】
本発明で用いられる導電たいそう及び導電体層の片面に突出する複数の導電性突起を有する配線部材としては、例えば、下記の１、２が挙げられる。
１．表面に導電性突起を有する金属箔。このような金属箔としては、例えば、導電体層として少なくとも第３金属の層を有し、導電体層表面の複数の導電性突起として、第２金属の層と第２金属の層上の第１金属の層の２層からなる複数の突起を有するもの、又は、導電体層として少なくとも第３金属の層と、第３金属の層上の第２金属の層とからなる複合層と、導電体層表面の複数の導電性突起として、第２金属の層上の第１金属からなる複数の突起を有するものが挙げられる。
２．導電性突起を有した導体と絶縁樹脂からなる配線部材。例えば、配線部材が、絶縁樹脂層、絶縁樹脂層両面上の層間接続された導電体層、及び絶縁樹脂層の少なくとも片面上の導電体層上に導電性突起を有するもの。この場合、通常、少なくとも導電性突起を有する導電体層は、回路を形成している。
【００３１】
上記の表面に導電性突起を有する金属箔は、例えば、第１金属からなる第１金属層、第２金属からなる第２金属層及び第３金属からなる第３金属層の少なくとも３層をこの順で有する多層金属箔を用い、第１金属層を部分的に第２金属層が露出するまで除去することにより、第２金属層及び第３金属層からなる導電体層及び第１金属からなる複数の導電性突起を形成することにより作製するか、又は、該多層金属箔を用い、第１金属層及び第２金属層を部分的に第３金属層が露出するまで除去することにより、第３金属層からなる導電体層及び第２金属の層と第２金属の層上の第１金属の層とからなる複数の導電性突起を形成することにより作製することができる。例えば、多層金属箔として、第１金属と第２金属とが、互いにエッチング条件の異なる金属であり、第２金属と第３金属とが、互いにエッチング条件の異なる金属であるものを用い、第１金属層の部分的な除去をエッチングにより行なうか、又は、第１金属層及び第２金属層の部分的な除去を、互いに異なるエッチング条件下で順次エッチングして行なう。より具体的には、第１、第３の金属層が第２金属層とエッチング条件の異なる金属層である３層の金属箔を、ドライフィルムレジストを用いたエッチングにより第１金属層を複数の柱状バンプにして導電性突起とするか、上記の３層の金属箔を、ドライフィルムレジストを用いたエッチングにより第１金属層を複数の柱状バンプとし、次いで第２金属層を、柱状バンプの下部を除いて第３の金属層が露出するまでエッチング除去して導電性突起とする。
【００３２】
上記の多層金属箔において、第１金属層としては、例えば、銅、銅合金、鉄・ニッケル合金等から選択したものを用いることができる。第２金属層としては、例えば、第１金属層が銅又は銅合金である場合には、ニッケル、ニッケル合金、チタン、クロム、錫、亜鉛、金等を用いることができ、第１金属層が鉄・ニッケル合金の場合には、チタン、クロム、錫等を用いることができる。第３金属層としては、例えば、第２金属層がニッケル、ニッケル合金、チタン、クロム、錫、亜鉛、金等である場合には、銅又は銅合金等を用いることができ、第２金属層がチタン、クロム、錫等である場合には、鉄・ニッケル合金等を用いることができる。ここで、エッチング条件が異なる金属層とは、１種類のエッチング液に対して、浸食性が高い金属層と低い金属層、あるいは、各々異なるエッチング液に対する浸食性を有する金属を意味する。
上記の導電性突起を有した導体と絶縁樹脂からなる配線部材としては、例えば、上記の表面に導電性突起を有する金属箔に、導電性突起の先端面を露出させて樹脂層を形成したものの樹脂層形成面に、更に上記３層金属箔を加熱圧着し、その後、同様に第１金属層又は第１金属層と第２金属層を柱状バンプにエッチングして導電性突起としたものがある。また、一般的な両面配線板の表面に、銀ペースト等の導電性樹脂を印刷して導電性突起を形成したもの、めっきレジスト等を使用して、めっき析出で金属突起を形成したものも含む。
【００３３】
第１金属層、第２金属層及び第３金属層の少なくとも３層を有する多層金属箔の場合、柱状バンプを形成する第１金属層の厚さは、１２〜１００μｍであることが好ましく、１００μｍを超えると、金属柱又は外部接続端子を形成するときのエッチング精度が低く、微細なパターンの形成が困難になるおそれがあり、１２μｍ未満であると、導電性突起の強度が不十分となったり、絶縁樹脂による絶縁性が低下するおそれがある。より好ましくは、１８〜７０μｍである。第２金属層の厚さは、０．０５〜５０μｍであることが好ましく、５０μｍを超えると、回路形成時のエッチング精度が低く、微細なパターンの形成が困難になるおそれがあり、０．０５μｍ未満であると、第１金属層をエッチングするときに、第２金属層に発生したピットや欠けのために、第３金属層が浸食されるおそれがある。より好ましくは、０．１〜３５μｍである。第３金属層の厚さは、１〜５０μｍであることが好ましく、５０μｍを超えると、回路の形成時にエッチング精度が低下し、微細なパターンの形成が困難になるおそれがあり、１μｍ未満であると、第１金属層をエッチングするときに、第２金属層に発生したピットや欠けのために、第３金属層が浸食されるおそれがある。また第３金属層に回路を形成しその上に積層する場合、回路間の埋め込み性をよくするためには、第３金属層は薄い方がよい。より好ましくは、５〜１２μｍである。
【００３４】
導電性突起の形状は、中実の柱状であれば特に制限はなく、通常、半径１０〜７５０μｍの円柱、一辺が２０μｍ〜１０００μｍの方形等である。
【００３５】
積層用中間配線部材Ａ及びＢ並びにそれらの製造方法に用いる絶縁樹脂としては、塗布時に流動性があり（このとき、塗布環境は常温でもよく、あるいは絶縁樹脂に流動性が得られる様に加熱してもよい）、塗布後、乾燥等によって研磨できるような流動性のない状態になり、かつ後の積層のための貼り付け時、加圧、加熱、又は反応基の賦与等により再接着が可能である樹脂であればよい。例としては、ポリイミド樹脂、ポリアミドイミド樹脂、シリコーン変性ポリアミドイミド樹脂、シリコーン樹脂、フェノール樹脂、ビスマレイミドトリアジン樹脂、エポキシ樹脂、アクリル樹脂等の熱硬化性樹脂、ポリフェニレンサルファイド樹脂、感光性ポリイミド樹脂、アクリルエポキシ樹脂、エチレン、プロピレン、スチレン、ブタジエン等の熱可塑性エラストマー、液晶ポリマー等がある。また、これらの樹脂に有機粒子や無機粒子を配合したものも使用することができる。樹脂に配合することができる有機粒子の例としては、前述の樹脂の硬化物、無機粒子の例としてはアルミナ粒子、二酸化ケイ素（シリカ）、ガラス繊維等がある。これらの有機又は無機粒子の粒径は、平均粒径が０．１〜２０μｍであることが好ましい。絶縁樹脂中に有機又は無機の粒子を配合する目的として、硬化収縮の低減と熱膨張係数の調整等が挙げられる。硬化収縮量は、粒子の配合量を多くすればするほど低減できるが、相対的に樹脂量が少なくなり、接着力が小さくなるため、配合量は絶縁樹脂総量中の９０重量％以下が望ましい。熱膨張係数の調整には、無機粒子を配合することが多い。配合量は、接着する部材の膨張係数と合わせるように調整するが、配合量を多くすると接着力が低下するため、配合量は、絶縁樹脂総量中の９０重量％以下が望ましい。例えば、シリカ粒子で接着部材が銅の場合、配合量は絶縁樹脂総量中の４０〜８０重量％が望ましい。
【００３６】
積層用中間配線部材Ａ及びＢの製造方法の絶縁樹脂印刷工程では、硬化前の流動状のワニス状態にある絶縁樹脂を、配線部材の導電性突起を有する表面に、積層用中間配線部材Ａの作製時には導電性突起及び半硬化状態の導電性樹脂が絶縁樹脂で埋め込まれる厚みに、積層用中間配線部材Ｂの作製時には導電性突起が絶縁樹脂が埋め込まれる厚みに、印刷により塗布する。流動状のワニス状態にある絶縁樹脂は、印刷時に粘度が３〜７０Ｐａ・ｓであることが好ましい。印刷方法としては、メッシュスクリーンマスク、メタルマスク等を用いたスクリーン印刷法、及び配線部材上に直接スキージ、ブレード等を用いて、すり切り又は隙間を空けて均一な厚みに絶縁樹脂を塗布する方法、及び樹脂をドラム又はボード等に塗布した後、配線部材上に絶縁樹脂を転写する方法等がある。また、これら作業を真空下で行なう方法も、未充填箇所をなくすには有効である。
【００３７】
積層用中間配線部材Ａ及びＢならびにそれらの製造方法で使用する導電性樹脂としては、絶縁樹脂と同様に塗布時に流動性があり（塗布環境は常温でもよく、あるいは導電性樹脂に流動性が得られる様に加熱してもよい）、塗布後、乾燥等によって研磨できるような流動性のない状態になり、かつ後の積層のための貼り付け時、加圧、加熱、又は反応基の賦与等により再接着が可能である導電性樹脂であればよい。この導電性樹脂に使用されるバインダの例としては、ポリイミド樹脂、ポリアミドイミド樹脂、シリコーン変性ポリアミドイミド樹脂、シリコーン樹脂、フェノール樹脂、ビスマレイミドトリアジン樹脂、エポキシ樹脂、アクリル樹脂等の熱硬化性樹脂、ポリフェニレンサルファイド樹脂、感光性ポリイミド樹脂、アクリルエポキシ樹脂、エチレン、プロピレン、スチレン、ブタジエン等の熱可塑性エラストマー、液晶ポリマー等がある。また、これらの樹脂に配合する導電性粒子の例としては、金粒子、銀粒子、銅粒子、はんだ粒子、カーボン粒子、ニッケル粒子、アルミ粒子、チタン粒子、鉄粒子等、これら粒子の混合粒子、これら金属の合金粒子、及び、無機又は有機粒子へのこれら金属及び合金のコーティング品等がある。これらの粒径は、平均粒径が０．５〜２０μｍであることが好ましい。導電性粒子の配合量は、一般的には十分な導電性を得るために８０重量％以上の配合が必要であるが、本発明においては、金属箔等との積層時に加熱加圧することで導電性突起と積層する金属箔間の導電が得られればよく、乾燥状態及び加圧なしで硬化した状態では導電性がなくてもよい。そのため、より少ない配合量で加熱加圧硬化後の導電性を得ることができる。すなわち、樹脂比率を高くできるので、より接着性を高くすることができる。例えば、導電性樹脂の積層接合後の厚みに対してそれより同等以上の大きさの金属粒子を使用した場合、加熱加圧することで金属粒子が直接、導電性突起と金属箔とに接触するため、数個の金属粒子（接合箇所１箇所に対して）で接合を得ることができる。また、２種類以上の金属粒子を配合する場合において、積層時の加熱温度と１種類の金属粒子の溶融温度を同等にすることで、加圧加熱時に金属粒子間の金属接合が進み、かつ導電性突起及び金属箔との金属接合も行なわれるため、より少ない配合量で導電性を得ることができる。従って、導電性粒子の配合量としては、導電性粒子とバインダとの総量中、導電性粒子３０〜９０重量％が好ましく、４０〜８０重量％がより好ましい。
【００３８】
なお、本明細書中、絶縁樹脂及び導電性樹脂の半硬化状態とは、流動性がなくなり、研磨可能な状態に硬化されたもので完全な硬化に至っていない状態を指す。熱硬化性樹脂ではＢステージ状態と呼ばれ、樹脂により異なるが、一般的に硬化率が３０〜８０％のものを指す。この硬化率は、ＤＳＣ（示差走査熱分析）により測定することが可能である。絶縁樹脂の半硬化状態までの乾燥は、絶縁樹脂が熱硬化性樹脂の場合、加熱により行ない、研磨時の室温（５〜３５℃）に戻した状態において、流動性がなく、外力を加えた際に弾性変形又は塑性変形し、外圧をなくすと弾性変形の場合は元の状態に戻り、塑性変形した場合には変形した状態を維持するような状態が研磨可能な状態である。
溶剤希釈タイプの熱可塑性材料の場合、溶剤分を適度に除去することにより、半硬化状態にすることができる。溶剤分を除去する方法としては、加熱又は減圧する方法等がある。熱硬化性樹脂と同様、研磨可能な状態とは、流動性がなく、外力を加えた際に、弾性変形又は塑性変形し、外圧をなくすと弾性変形の場合は元の状態に戻り、塑性変形した場合は変形した状態を維持するような状態である。
【００３９】
感光性ポリイミド等、感光性樹脂を使用する場合、紫外線照射量により硬化量を制御することができる。また、感光性樹脂の場合は、導電性突起上部をマスキング等により紫外線が当たらないようにし、導電性突起部以外の部分の紫外線照射量より紫外線照射量を低減し、導電性突起上部が他の部分より未硬化の状態にすることで、導電性突起上部をより集中して研磨ができ、研磨効率を上げることができる。さらに、この感光性樹脂が露光部分とそれ以外の部分とを薬液で除去できるタイプであれば、導電性突起上部とそれ以外の部分の紫外線照射量を変えることで、導電性突起上部の樹脂のみ薬液で除去することができ、研磨なし、又はわずかな研磨で導電性突起上部の頭出しができる。
【００４０】
絶縁樹脂印刷工程において、絶縁樹脂としては、１種類のみを用いて単層の絶縁樹脂層を形成してもよいし、２種類以上の絶縁樹脂、同一組成の樹脂にフィラー等の充填率を変えたものも含めて、これらを用いて、多層絶縁樹脂層を形成してもよい。各層の樹脂の配合成分、樹脂種類、厚み、或いは層数を変えることで、配線部材を多層化する際の厚み制御、層間ズレ、全体のそり量を制御できる。また、多層絶縁樹脂層とする場合、第１層の樹脂を、部材の種類、表面状態に合わせ選択することで接着性の良い層とすることは重要であり、また樹脂層中央は配線部材の積層時に固く流動しにくい状態である樹脂層であることがのぞましい。また反対に配線部材と接着する表面層の樹脂は密着性が高く、接着時に流動性のある樹脂を使用するとよい。
【００４１】
例えば、配線部材の導電性突起を有する面に、流動状のワニス状態にある、接着性がよく、半硬化状態で別の配線部材を接着する際固く流動しにくい第１絶縁樹脂を印刷し、流動性はなくなるが、完全な硬化に至るまえの、半硬化状態まで乾燥し、次いで、第１絶縁樹脂と成分が異なり、流動状のワニス状態にある、接着性がよく、半硬化状態で別の配線部材を接着する際柔らかく流動しやすい絶縁樹脂を印刷し、流動性はなくなるが、完全な硬化に至るまえの、半硬化状態まで乾燥することにより、第１絶縁樹脂のコア層と第２絶縁樹脂の表面層の少なくとも２層からなる多層絶縁樹脂層を、導電性突起又は導電性突起及び導電性樹脂が絶縁樹脂で埋め込まれる厚みに形成する。これにより、中央部のコア層となる樹脂層で加圧時の基材の変形を防ぎ、かつ表層の流動性のある樹脂層により埋込性、密着性をよくすることが出来る。比較的柔らかい表面層用の第１絶縁樹脂と、比較的固いコア層用の第２絶縁樹脂の組み合わせとしては、例えば、第１絶縁樹脂として樹脂を用い、第２絶縁樹脂として、樹脂１００重量部に対して無機又は有機フィラーを４０〜９０重量部、好ましくは５０〜８０重量部配合した組成物を用いる組み合わせが挙げられる。また、コア層と表面層の厚みは、表面層としては、十分な埋め込み性と接着性を得るためには１０μｍ以上の厚みが好ましく、コア層の厚みとしては全体絶縁樹脂厚に対して５０〜９０％を占めていることが望ましい。
【００４２】
積層用中間配線部材Ａ及びＢの製造方法の導電性樹脂塗布工程において、配線部材の導電性突起の先端面上に導電性樹脂を塗布する方法として、まず導電性樹脂の粘度は、印刷時に３〜７０Ｐａ・ｓであることが好ましい。印刷方法としては、メッシュスクリーンマスク、メタルマスク等を用いたスクリーン印刷法、導電性樹脂をドラム又はボード等に塗布した後、配線部材上に樹脂を転写する方法、ディスペンサーにより塗布するディスペンス法等がある。
【００４３】
本発明の特徴として、導電性突起上に導電性樹脂を塗布するため、積層用中間配線部材Ａの製造方法においては、ずれて塗布しても表面張力により導電性突起下部に導電性樹脂が流れることはなく、また塗布樹脂量がばらついても塗布範囲が導電性突起上に限定されるため、塗布の位置合わせ、塗布量の制御が容易である。さらに平面に導電性樹脂を塗布するのに比べ、同量の樹脂量ではより小さい範囲に塗布できるため狭ピッチの回路形成に対応しやすい。また、積層用中間配線部材Ｂの製造方法においては、凹部に導電性樹脂を供給することから、だれることがなく、一定の位置に一定量の導電性樹脂を供給しやすくなる。また、積層用中間配線部材Ａに比べ、導電性樹脂部を研磨しないので、絶縁樹脂部分に導電性異物が付着しにくい。
【００４４】
導電性樹脂の接着性をよくするためにはバインダとなる樹脂成分の比率を大きくする必要があるが、樹脂成分を大きくすると抵抗値が高くなってしまう。本発明では、導電性突起の上に導電性樹脂を塗布するため、同高さの導電性突起を単一の導電性樹脂で形成するのに比べ、導電性樹脂を薄くすることが出来る。そのため、樹脂成分の多い導電性樹脂であっても抵抗値を低くすることが出来る。
【００４５】
積層用中間配線部材Ａ及びＢの製造方法において、研磨工程における研磨方法としては、ロールペーパー研磨、サンドブラスト法、ホーニング、ラッピング等があり、また刃物を使用した機械加工法、例えばルータ加工等でもよい。また、絶縁樹脂又は絶縁樹脂及び導電性樹脂を半硬化状態で研磨をすることは、硬化状態に比べ硬度が低いため、研磨効率を上げることができる。積層用中間配線部材Ａの製造方法においては、導電性突起先端面に導電性樹脂を塗布しないで絶縁樹脂を塗布して乾燥する方法と比較して、導電性突起部の研磨性もよくなる。さらに導電性突起が金属等の固い突起である場合、導電性樹脂を塗布しない方法では、研磨工程において固いところほど削れにくいため、研磨後の導電性突起部表面が凸状になりやすいが、導電性樹脂を塗布した方法では、導電性樹脂が半硬化状態であることから導電性突起部表面も平坦になりやすい。絶縁樹脂と導電性樹脂の半硬化状態の硬度が同等又は近いことは、研磨時の平坦性を向上するうえで有効である。一方、積層用中間配線部材Ｂの製造方法においては、研磨時には導電性突起先端面上に導電性樹脂は塗布されていないため、研磨後に、導電性突起部表面が凸状になりやすい。しかし、その後、導電性突起をハーフエッチングして凹部を形成し、その凹部で導電性突起の先端面上に導電性樹脂を塗布するため、凸状態は解消され、ほぼ平坦な表面を形成することができる。
【００４６】
配線部材と絶縁樹脂、導電性樹脂との接着において、配線部材の絶縁樹脂及び導電性樹脂と接触する面を予め粗化しておくことは密着性を向上する上で有効である。粗化の方法としては、化学粗化（化学リン系処理、化学リン酸系処理、化学蟻酸系処理等のエッチング等）でも、機械的粗化（ブラスト加工等）でも、プラズマ処理、金属粒の電解付与等でもよい。
この際、導電性突起頭部の表面だけでなく、導電性突起部の少なくとも側面、好ましくは更に導電体層の絶縁樹脂と接着する面も同時に粗化できる条件を選ぶことも重要である。
また導電性樹脂と接続する部分は、粗化時によって導電性を阻害する膜を生成することは好ましくない。電気特性上問題になる場合は導電性樹脂と接着する部分を粗化する前にマスキングするか、粗化した後、導電性樹脂と接着する部分の導電性を阻害する膜をエッチング等により部分除去するとよい。
【００４７】
積層用中間配線部材Ａの平坦化面上、又は、積層用中間配線部材Ｂの平坦化絶縁樹脂面上に、加熱加圧によって接着した導電体回路を形成し、半硬化状態の絶縁樹脂及び半硬化状態の導電性樹脂を硬化させ、導電体層を部分エッチングにより回路形成することを含む方法により、本発明の配線板を製造することができる。
本発明の方法で製造される配線板としては、例えば、半導体パッケージに用いられるインターポーザーとしての半導体パッケージ用基板、半導体パッケージやその他の電子部品を搭載するマザーボード等のその他配線板が挙げられる。
積層用中間配線部材Ａ又はＢの平坦化面又は平坦化絶縁樹脂面上に導電体回路を形成する方法としては、例えば、金属箔を加熱加圧によって接着した後、接着した金属箔を部分エッチング等によって回路形成する方法がある。また、片面に回路形成された配線板、片面の金属箔が回路形成された両面金属箔張り基板、内層回路を有し、片面に外層回路を有する多層回路基板等を用い、回路面又は外層回路面を積層用中間配線部材Ａの平坦化面、又は、積層用中間配線部材Ｂの平坦化絶縁樹脂面と接触させて積層し、加熱加圧によって接着してもよい。
【００４８】
例えば、下記のようにして、本発明の積層用中間配線部材Ａ又はＢを用いて、２層配線板を製造することができる。まず、積層用中間配線部材Ａの平坦化面上、又は、積層用中間配線部材Ｂの平坦化絶縁樹脂面に、金属箔を戴置し、圧力及び熱を加えることで金属箔と積層用中間配線部材Ａとを接着し、かつ、半硬化状態の絶縁樹脂及び半硬化状態の導電性樹脂を硬化させる。次いで、積層用中間配線部材Ａ又はＢの導電体層と、接着した金属箔とを、各々部分エッチングにより回路形成することにより、２層配線板を製造することができる。
【００４９】
金属箔としては、例えば、銅箔、アルミ箔、ニッケル箔、４２アロイ箔等を用いることができ、厚みは１２〜４０μｍであることが好ましい。後述の他の配線板の製造方法において用いられる金属箔も、同様である。
【００５０】
積層用中間配線部材Ａ又はＢと金属箔との接着方法として、真空下でプレス加圧、加熱するプレス方法とロールにより加圧加熱するラミネート法等がある。加熱加圧は、通常、温度１５０〜３００℃、圧力０．４９〜９．８ＭＰａ（５〜１００ｋｇｆ／ｃｍ^２）で行なうことが好ましい。この際、金属箔に予め接着性をよくするための接着促進剤等を塗布しておいてもよい。但し導電性樹脂との接着において金属箔との導電性を阻害しない程度とする。この接着方法は、下記の他の配線板の製造方法においても、同様である。
【００５１】
なお、絶縁樹脂及び導電性樹脂の硬化は、これらの樹脂が熱硬化性樹脂を含有する場合には、金属箔との加圧加熱による接着時に、同時に行なうことができる。また、これらの樹脂が熱可塑性材料である場合には、軟化点まで温度を上げることで接着可能になるが、軟化して流動性が高いと平坦性が得られなくなるので、流動しないが接着する状態に温度・圧力を制御しなければならない。感光性樹脂の場合の硬化は、加熱することで進行するが、不十分な場合は外装回路形成後、光照射し十分感光することで硬化させる。以下の方法においても、同様である。
また、積層用中間配線部材Ａ又はＢと、更に別の積層用中間配線部材Ａ又はＢを含む（Ａ又はＢ同士であっても、Ａ及びＢの両方を用いてもよい。）他の配線部材とを用いることによって、３層以上の多層配線板を製造することができる。
【００５２】
例えば、次のようにして、積層用中間配線部材Ａ又は積層用中間配線部材Ｂを少なくとも２つ用いて多層配線板を製造する。積層用中間配線部材Ａの平坦化面に、金属箔を戴置し圧力及び熱を加えることで金属箔と積層用中間配線部材Ａとを接着しかつ半硬化状態の絶縁樹脂及び半硬化状態の導電性樹脂を硬化する。次いで、積層用中間配線部材Ａの導電体層及び／又は接着した金属箔を部分エッチングして回路形成して配線部材Ｃを作製する。積層用中間配線部材Ａ′と配線部材Ｃとを、積層用中間配線部材Ａ′の平坦化面と配線部材Ｃの回路とが接触するように積層し、圧力及び熱を加えることで配線部材Ｃと積層用中間配線部材Ａ′とを接着しかつ積層用中間配線部材Ａ′の半硬化状態の絶縁樹脂及び半硬化状態の導電性樹脂を硬化する。その後、積層用中間配線部材Ａ′の導電体層と、接着した配線部材Ｃの回路形成されていない導電体層又は金属箔とを、部分エッチングにより回路形成することにより、多層配線板を得る。これを繰り返すことにより、更に多層化することができる。少なくとも２つの積層用中間配線部材Ｂを用いる場合は、積層用中間配線部材Ｂを用いて、上記と同様にして配線部材Ｄを製造し、次いで配線部材Ｄと別の積層用中間配線部材Ｂ′を用い、上記と同様の工程を経て多層配線板を製造する。
【００５３】
半硬化状態の導電性樹脂を塗布せず、導電性突起の先端面を絶縁樹脂表面に露出させた配線部材Ｅと、積層用中間配線部材Ａ又はＢとを用いて、次のようにして多層配線板を製造することもできる。まず、第１金属からなる第１金属層、第２金属からなる第２金属層及び第３金属からなる第３金属層の少なくとも３層をこの順で有し、第１金属と第２金属とが互いにエッチング条件の異なる金属であり、第２金属と第３金属とが互いにエッチング条件の異なる金属である多層金属箔を用意する。多層金属箔の第１金属層を第２金属層が露出するまで部分的にエッチングすることにより、第２金属層の露出面上に第１金属からなる複数の導電性突起を形成し、あるいは、第１金属層及び第２金属層をこの順で第３金属層が露出するまで各々部分的にエッチングすることにより、第３金属層の露出面上に第１金属の層及び第２金属の層の２層からなる複数の導電性突起を形成する導電性突起を形成する（導電性突起形成工程）。次いで、第２金属層の露出面上又は第３金属層の露出面上に、硬化前の流動状のワニス状態にある絶縁樹脂を、印刷により、導電性突起が絶縁樹脂に埋め込まれる厚みに塗布する（印刷工程）。その後、印刷した絶縁樹脂を、半硬化状態に乾燥又は又は完全な硬化状態に乾燥又は硬化させる（乾燥又は硬化工程）。次いで、半硬化状態又は硬化した絶縁樹脂を研磨することにより、絶縁樹脂表面に導電性突起の先端面を露出させ、かつ絶縁樹脂表面を平坦化する（研磨工程）。その後、エッチングされていない第２金属層及び第３金属層又はエッチングされていない第３金属層を部分エッチングして回路を形成することにより回路面を形成することにより、配線部材Ｅを作製する配線部材Ｅと積層用中間配線部材Ａ又はＢとを、配線部材Ｅの回路面と積層用中間配線部材Ａの平坦化面又は積層用中間配線部材Ｂの平坦化絶縁樹脂面とが接するように積層し、圧力及び熱を加えることで配線部材Ｅと積層用中間配線部材Ａとを接着しかつ半硬化状態の絶縁樹脂及び半硬化状態の導電性樹脂を硬化させる。その後、積層用中間配線部材Ａ又はＢの導電体層を部分エッチングして回路形成することにより、多層配線板を製造する。
【００５４】
また、積層用中間配線部材Ａの平坦化面又は積層用中間配線部材Ｂの平坦化樹脂面上への回路形成を、導電性樹脂を印刷により塗布して行なったものを用いてもよい。例えば、積層用中間配線部材Ａの平坦化面に、導電性樹脂をスクリーン印刷して回路を形成し、流動性はなくなるが完全な硬化状態に至る前の、半硬化状態まで乾燥する。次いで、導電性樹脂の回路を形成した積層用中間配線部材Ａと、別の積層用中間配線部材Ａ′とを、積層用中間配線部材Ａの回路形成した面と積層用中間配線部材Ａ′の平坦化面とが接するように積層し、圧力及び熱を加えることで積層用中間配線部材Ａと積層用中間配線部材Ａ′とを接着しかつ半硬化状態の絶縁樹脂及び半硬化状態の導電性ペーストを硬化させる。次いで、積層用中間配線部材Ａの導電体層と積層用中間配線部材Ａ′の導電体層を部分エッチングして回路形成することにより、多層配線板を得る。同様の工程で、２つ以上の積層用中間配線部材Ｂ、又は、積層用中間配線部材Ａ及び積層用中間配線部材Ｂの少なくとも２つを用いて、多層配線板を製造することもできる。
【００５５】
【実施例】
以下、本発明の実施例によって本発明をさらに具体的に説明するが、本発明はこれら実施例に限定されるものではない。
実施例１
図に基づいて本発明の一実施例を説明する。図１は、導電性突起に導電性樹脂を塗布乾燥し、次いで絶縁樹脂を塗布乾燥、研磨して導電性突起部の先端面を露出させたて積層用中間配線部材Ａを作製した後、金属箔を加圧加熱により接着し両面に回路形成して２層配線板を作製した工程図である。ここで導電性突起を有する配線部材は、以下の様にして製作した。厚さ７０μｍの銅層（第１金属層１）、０．２μｍのニッケル層（バリア層としての第２金属層２）、１０μｍの銅層（導電体層３）からなる３層の金属箔（日本電解（株）製）を用意した（図１（ａ））。フォトドライフィルムＨ−Ｋ３５０（日立化成工業（株））を用いて、厚さ７０μｍの銅層（第１金属層１）側にパターンを形成し、メルテックス社製エープロセス液（アンモニア銅錯塩２０〜３０重量％、塩化アンモニウム１０〜２０重量％及びアンモニア１〜１０重量％含有）からなるアルカリエッチング液で７０μｍの銅層（第１金属層１）を選択的にエッチングして、複数の柱状バンプ４を形成した（図１（ｂ））。露出したニッケル層（第２金属層２）の柱状バンプ４の下以外の部分を、硝酸・過酸化水素水溶液（硝酸１０重量％、過酸化水素５重量％）からなるエッチング液で選択的に除去した。これにより、厚さ１０μｍの銅層からなる導電体層５表面に、銅層及びニッケル層からなるφ２５０μｍの複数の円柱状の導電性突起６を形成した配線部材を作製した（図１（ｃ））。露出した１０μｍの銅層（導電体層５）の表面及び導電性突起の側面・上面に、樹脂との密着をよくするために化学リン酸系処理で２μｍ粗化処理を施した。
【００５６】
次に導電性樹脂７（エポキシ系銀ペースト１１８−０６ＳＤＣｒｅａｔｉｖｅｍａｔｅｒｉａｌｓｉｎｃｏｒｐｏｒａｔｅｄ）、粘度２５Ｐａ・ｓを用いて、導電性突起６に対応して直径φ１５０μｍの穴の開いた厚さ５０μｍのメタルマスクを用意し、樹脂製スキージにて導電性突起６の先端面に導電性樹脂７を印刷供給した。その後１２０℃５分乾燥することで、導電性樹脂７は半硬化状態となった（図１（ｄ））。このときの導電性樹脂７の厚みは３０μｍであった。
絶縁樹脂８としてシリコーン変性ポリアミドイミド樹脂からなるＫＳ６６００（日立化成工業（株）製、固形分濃度：３０重量％）を用いた。流動状のワニス状態の粘度４０Ｐａ・ｓの状態の絶縁性樹脂８を、印刷機（ＶＥ−５００東レエンジニアリング（株）製）で複数の導電性突起６及び導電性樹脂７の全てを埋め込んで塗布できる様に開口した厚さ１５０μｍのメタルマスクを介して、導電体層５上に印刷した。１２０℃３０分乾燥すると、絶縁樹脂８は半硬化状態となり、図１（ｅ）のように溶剤分が揮発して導電性突起６の上部が盛り上がった断面形状となった。導電性突起６の上部の絶縁樹脂８の厚みは、３０μｍであった。
【００５７】
図１（ｆ）に示すように、絶縁樹脂８に埋め込まれた導電性樹脂７付きの導電性突起６の導電性樹脂７の先端面を露出させるため、半硬化状態の絶縁樹脂８を市販の研磨紙で平坦に研磨する様に注意しながら研磨した。導電性樹脂７が厚さ１０〜２０μｍ残る様に研磨したところで研磨を終了した。平坦化面９に露出した導電性樹脂７の露出面の径はφ１２０μｍであった。
これにより積層用中間配線部材Ａを形成できた。
次に図１（ｇ）のように、この積層用中間配線部材Ａと銅箔（金属箔１０）を、真空プレスを用いて平坦化面９上で張り合わせた。銅箔（金属箔１０）は厚み３５μｍで、接着面は樹脂との密着をよくするために化学リン酸系処理で２μｍ粗化処理を施した。接着条件は真空下で１８０℃６０分加熱後２６０℃２０分加熱、プレス圧力０．８ＭＰａで行った。張り合わせた銅箔（金属箔１０）と、銅からなる導電体層５に、銅の部分エッチング（塩化第２鉄濃度３５重量％、塩酸濃度３重量％の水溶液）により回路１１を形成し、図１（ｈ）のような２層配線板を製作した。
【００５８】
実施例２
図２は、導電性突起に絶縁樹脂を塗布乾燥、研磨して導電性突起部の頭を出しした後、導電性突起部をハーフエッチングしてエッチングした部分に導電性樹脂を埋込塗布、乾燥して積層用中間配線部材Ｂを作製したのち、金属箔を加圧加熱により接着し両面に回路形成して２層配線板を作製した工程図である。図２（ａ）、図２（ｂ）及び図２（ｃ）の工程は、実施例１の図１（ａ）、図１（ｂ）及び図１（ｃ）の工程と同様に行ない、導電性突起を有した配線部材を製作した。次に絶縁樹脂８として、シリコーン変性ポリアミドイミド樹脂からなるＫＳ６６００（日立化成工業（株）製）を用い、流動状のワニス状態の粘度４０Ｐａ・ｓの状態にある絶縁樹脂８を、印刷機（ＶＥ−５００東レエンジニアリング（株）製）で、複数の導電性突起６の全てを埋め込んで塗布できる様に開口した厚さ１２０μｍのメタルマスクを介して、導電体層５上に印刷した。１２０℃３０分乾燥することで絶縁樹脂８は半硬化状態となり、図２（ｄ）のように溶剤分が揮発して導電性突起６の上部が盛り上がった断面形状となった。導電性突起６の上部の絶縁樹脂８の厚みは、３０μｍであった。
【００５９】
図２（ｅ）に示すように、絶縁樹脂８に埋め込まれた導電性突起６の先端面を露出させるため、半硬化状態の絶縁樹脂８を市販の研磨紙で平坦に研磨する様に注意しながら研磨した。導電性突起８の先端面が完全に露出するまで研磨したところで研磨を終了した。平坦化絶縁樹脂面１２に露出した導電性突起６の露出部の径はφ２５０μｍであった。次に導電体層５をエッチングされない様に保護テープで保護し、銅からなる導電性突起６を酸系エッチング液（塩化第２鉄濃度３５重量％、塩酸濃度３重量％の水溶液）により、平均２０μ程度ハーフエッチングすることで、図２（ｆ）のように、平坦化絶縁樹脂面１２に、導電性突起６の先端面２を底とする凹部１３が形成された。
次に導電性樹脂７（エポキシ系銀ペースト１１８−０６ＳＤＣｒｅａｔｉｖｅｍａｔｅｒｉａｌｓｉｎｃｏｒｐｏｒａｔｅｄ）、粘度２５Ｐａ・ｓを用いて、導電性突起６に対応して直径φ２００μｍの穴の開いた厚さ３０μｍのメタルマスクを用意し、樹脂製スキージにてハーフエッチングされた導電性突起６の先端面上に導電性樹脂７を印刷供給した。その後１２０℃５分乾燥することで導電性樹脂７は半硬化状態となった（図２（ｇ））。このときの導電性樹脂７の厚みは２０μｍであった。これにより積層用中間配線部材Ｂを形成できた。
【００６０】
次に図２（ｈ）のように、この積層用中間配線部材Ｂと銅箔（金属箔１０）を、真空プレスを用いて、平坦化絶縁樹脂面１２上で張り合わせた。銅箔（金属箔１０）は厚み３５μｍで、接着面は樹脂との密着をよくするために化学リン酸系処理で２μｍ粗化処理を施した。接着条件は真空下で１８０℃６０分加熱後２６０℃２０分加熱、プレス圧力０．８ＭＰａで行った。張り合わせた銅箔（金属箔１０）と導電体層５に、銅の部分エッチングにより回路１１を形成し、図２（ｉ）のような２層配線板を製作した。
【００６１】
実施例３
図３は、図１（ｅ）の絶縁樹脂塗布時に、組成の異なる絶縁樹脂を多数回塗布した例である。比較的固いコア層８ａを形成するための第１絶縁樹脂としては、シリコーン変性ポリアミドイミド樹脂からなるＫＳ６６００（日立化成工業（株）製）に平均粒径φ１．５μｍのシリカフィラ４０ｗｔ％含有（溶剤分揮発後）させたものを用いた。流動状のワニス状態の粘度８０Ｐａ・ｓの上記樹脂を、印刷機（ＶＥ−５００東レエンジニアリング（株）製）で、複数の導電性突起６部分の全部が埋め込まれるように塗布できる様に開口した厚さ５０μｍのメタルマスクを介して印刷した。１２０℃１０分乾燥することで、表面が半硬化状態となる。コア層８ａの厚みは、約５０μｍであった。次にＫＳ６６００（日立化成工業（株）製）のフィラレスのものを比較的柔らかい表面層８ｂ形成用の第２絶縁樹脂として用いて、流動状のワニス状態の粘度４０Ｐａ・ｓの上記樹脂を印刷機（ＶＥ−５００東レエンジニアリング（株）製）で複数の導電性突起６及び導電性樹脂７の全部を埋め込むように塗布できる様に開口した厚さ１００μｍのメタルマスクを介して、さらに印刷した。１２０℃２０分乾燥することで、第１絶縁樹脂及び第２絶縁樹脂全体が、半硬化状態となった。表面層８ｂの厚みは、約２０μｍであった。その結果、図３（ａ）のように、溶剤分が揮発して導電性突起部が盛り上がった、固い第１絶縁樹脂からなるコア層８ａと接着のよい柔らかい第２絶縁樹脂からなる表面層８ｂの２層構造の断面形状となった。
図３（ｂ）に示すように、絶縁樹脂８に埋め込まれた導電性樹脂７付きの導電性突起６の導電性樹脂７の端部を露出させるため、半硬化状態の２層構造の絶縁樹脂８の表面層８ｂを、市販の研磨紙で平坦に研磨する様に注意しながら研磨した。導電性樹脂７が厚さ１０〜２０μ残る様に研磨したところで研磨を終了した。導電性樹脂７の露出部の径はφ１２０μｍであった。
【００６２】
実施例４
図４は、実施例１において図１（ｆ）の積層用中間配線部材Ａと同様にして作製した積層用中間配線部材Ａ′と、配線部材Ｃとしての図１（ｈ）の２層配線板とを積層して３層配線板を作製する工程図である。積層用中間配線部材Ａ′は、導電性突起６′の径をφ１００μｍに、導電性樹脂７′の露出部の径をφ５０μｍに変更し、導電性突起６′の配置を変更した以外は、実施例１の積層用中間配線部材Ａと同様にして作製した。また、図４（ａ）のように、実施例１と同様にして、２層配線板を準備し、配線部材Ｃとして用いた。この際、配線部材Ｃの平坦化面９上の回路１１は、埋込性をよくするために、予め導電体層をハーフエッチングして厚みを５〜１０μｍまで薄くして、回路１１を形成した。図４（ｂ）のように、積層用中間配線部材Ａ′の研磨された平坦化面９′と配線部材Ｃの薄くした回路１１を有する面とを合わせて、真空プレスにて、圧力０．８ＭＰａで１８０℃６０分加熱後、２６０℃２０分加熱硬化し張り合わせた。その後図４（ｃ）のように、積層用中間配線部材Ａ′の導電体層５′を実施例１と同様の条件の部分エッチングによって外層回路を形成して３層配線板を製作した。
【００６３】
実施例５
図５は実施例４で作製した図４（ａ）の積層用中間配線部材Ａ′を利用した積層用中間配線部材Ａと、実施例２の工程中に作製した図２（ｅ）の構造を利用した配線部材Ｅとを積層して疑似３層の配線板を作製する工程図である。まず、実施例４と同様にして、積層用中間配線部材Ａ′を作製し、積層用中間用配線部材Ａとして用意する。また、図５（ｂ）に示すように、実施例２の図（ｄ）の状態から導電体層５に酸系エッチング液で回路１１を形成し、回路面１４を有する配線部材Ｅを準備する。図５（ｃ）のように、積層用中間配線部材Ａの平坦化面９と配線部材Ｅの回路面１４とを合わせて、真空プレスにて、圧力０．８ＭＰａで１８０℃６０分加熱後、２６０℃２０分加熱硬化し張り合わせた。その後図４（ｄ）のように、導電体層５を酸系エッチング液で回路１１を形成して疑似３層の配線板を製作した。
【００６４】
実施例６
図６は、積層用中間配線部材Ａの研磨された平坦化面に導電性ペーストで回路パターンを印刷したものと、別の積層用中間配線部材Ａ′とを積層して、多層配線案を作製する工程図である。まず図６（ａ）のように、実施例４と同様にして、図４（ａ）に示されると同じ積層用中間配線部材Ａ′を用意する。また、導電性突起６の配置を変更した以外は同じ工程によってつくられた積層用中間配線部材Ａの研磨面された平坦化面９に、導電性樹脂１５（エポキシ系銀ペースト１１８−０６ＳＤＣｒｅａｔｉｖｅｍａｔｅｒｉａｌｓｉｎｃｏｒｐｏｒａｔｅｄ）、粘度２５Ｐａ・ｓを用いて、回路パターンを印刷する厚さ３０μｍのスクリーンマスクを用意し、樹脂製スキージにて印刷した。その後１２０℃５分乾燥することで導電性樹脂１５は半硬化状態となり、図６（ｂ）に示される部材が得られた。このときの回路印刷した導電性樹脂１５の厚みは１０μｍであった。
図６（ｃ）のように、図６（ａ）の積層用中間配線部材Ａ′の平坦化面９′と、図６（ｂ）の積層用中間配線部材Ａの導電性樹脂１５で形成した回路面とを合わせて、真空プレスにて、圧力０．８ＭＰａで１８０℃６０分加熱後、２６０℃２０分加熱硬化し張り合わせた。その後図４（ｄ）のように、導電体層５及び導電体層５′を酸系エッチング液で部分エッチングして外層回路１１を形成して３層配線板を製作した。
【００６５】
実施例７
図７は実施例１の導電性樹脂の塗布面積を制限することでより高密度化に対応した配線板を製造する工程例である。導電性樹脂の塗布部分を除けば、実施例１と同じである。
まず、実施例１の図１（ａ）、図１（ｂ）、図１（ｃ）の工程と同様にして、表面に複数の導電性突起を有する配線部材を作製した。次いで、図７（ａ）に示すように、配線部材の導電性突起６の先端面上に、導電性樹脂７を塗布した。図７（ａ）の導電性樹脂塗布工程は、導電性樹脂７（エポキシ系銀ペースト１１８−０６ＳＤＣｒｅａｔｉｖｅｍａｔｅｒｉａｌｓｉｎｃｏｒｐｏｒａｔｅｄ）、粘度２５Ｐａ・ｓを用いて、導電性突起６に対応して直径φ７０μｍの穴の開いた厚さ５０μｍのメタルマスクを用意し、樹脂製スキージにて導電性突起６の先端面に導電性樹脂７を印刷供給した。その後１２０℃５分乾燥することで導電性樹脂７を半硬化状態とした。このときの導電性樹脂７の厚み（高さ）は３０μｍであった。
【００６６】
次いで、図７（ｂ）に示すように、実施例１と同様にして、絶縁樹脂８を塗布乾燥し、半硬化状態とした。その後、図７（ｃ）に示すように、実施例１と同様にして絶縁樹脂８を研磨し、導電性樹脂７の先端面が露出した平坦化面９を形成した。導電性樹脂７の露出した先端面の径は、φ５０μｍであった。次いで、図７（ｄ）に示すように、平坦化面９上に金属箔１０として銅箔を積層し、実施例１と同様に加熱加圧して接着し、かつ、絶縁樹脂８及び導電性樹脂７を硬化させた。次いで、図７（ｅ）に示すように、金属箔１０及び導電体層５を実施例１と同じ酸系エッチング液を用いて部分エッチングすることにより回路１１を形成し、２層配線板を作製した。また、図７（ｄ）に示す部材の金属箔１０のみを回路形成し、導電体層５をエッチングにより完全に除去することにより、疑似２層配線板を作製した。
【００６７】
【発明の効果】
以上説明したとおり、本発明の積層用中間配線部材は、各種配線部材と積層した時に、密着性、平坦性及び層間接続の信頼性に優れた積層面を形成することができる。また、この積層用中間配線部材を用いて作製される配線板は、層間の密着性、接続信頼性に優れ、しかも、平坦性に優れるものである。
【図面の簡単な説明】
【図１】本発明による積層用中間配線部材Ａの製造工程及びそれを用いた配線板の製造工程の一態様を示す工程図。
【図２】本発明による積層用中間配線部材Ｂの製造工程及びそれを用いた配線板の製造工程の一態様を示す工程図。
【図３】本発明による積層用中間配線部材Ａの他の態様の製造工程を示す工程図。
【図４】本発明による積層用中間配線部材Ａを用いて多層配線板を製造する一態様を示す工程図。
【図５】本発明による積層用中間配線部材Ａを用いて多層配線板を製造する他の態様を示す工程図。
【図６】本発明による積層用中間配線部材Ａを用いて多層配線板を製造する他の態様を示す工程図。
【図７】本発明による積層用中間配線部材Ａの製造工程の他の態様及びそれを用いた配線板の製造工程の一態様を示す工程図。
【符号の説明】
１第１金属層
２第２金属層
３第３金属層
４柱状バンプ
５、５′ 導電体層
６、６′ 導電性突起
７、７′ 導電性樹脂
８、８′ 絶縁樹脂
９、９′ 平坦化面
１０金属箔
１１回路
１２平坦化絶縁樹脂面
１３凹部
１４回路面
１５導電性樹脂[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an intermediate wiring member for lamination and a method for manufacturing the same, a wiring board and a substrate for a semiconductor package, and a method for manufacturing the same, and a multilayer wiring board, a multilayer substrate for a semiconductor package, and a method for manufacturing the same.
[0002]
[Prior art]
With the recent high-density mounting of electronic components, it has been required to improve the wiring density of wiring boards. Similar demands are increasing for semiconductor packages mounted on wiring boards. In general, in the case of a semiconductor package, there are a type in which input / output terminals are arranged in a single row around the package and a type in which input / output terminals are arranged in multiple rows not only in the periphery but also inside. The former is typically a QFP (Quad Flat Package). In order to increase the number of terminals, it is necessary to reduce the terminal pitch. However, in the region of 0.5 mm pitch or less, advanced technology is required for connection with a wiring board. The latter array type is suitable for increasing the number of pins because terminals can be arranged at a relatively large pitch. Conventionally, the array type is generally a PGA (Pin Grid Array) having connection pins, but the connection with the wiring board is of an insertion type and is not suitable for surface mounting. For this reason, a package called a surface mountable BGA (Ball Grid Array) has been developed.
[0003]
On the other hand, with the miniaturization of electronic devices, demands for further miniaturization of package sizes have increased. A so-called chip size package (CSP) having a size substantially equal to that of a semiconductor chip has been proposed as a device corresponding to the miniaturization. This is a package having a connection portion with an external wiring board, that is, an external connection terminal, in a mounting region, not in a peripheral portion of a semiconductor chip. As a specific example, a polyimide film with bumps is adhered to the surface of a semiconductor chip, the chip is electrically connected to the surface by gold lead wires, and then epoxy resin or the like is potted and sealed (for example, Non-Patent Document 1). And a method in which metal bumps are formed on a temporary substrate at positions corresponding to connection portions between a semiconductor chip and an external wiring board, and the semiconductor chip is face-down bonded and then transfer-molded on the temporary substrate (for example, Patent Document 2).
[0004]
All of these semiconductor packages use through holes and via holes for connection between the connection terminals and the semiconductor chip. For the through-holes and via-holes, a method is used in which holes are drilled or laser-coated in advance at the locations that will become the connection terminals on the base material, and solder or conductive paste is filled, and the connection terminals are provided by through-hole plating, hole filling plating, etc. Generally, in this method, there is a limit in reducing the diameter of the hole, and the cost increases as the number of pins increases.
Therefore, a method has been proposed in which conductive protrusions are provided on a metal foil in advance by plating, printing, or etching, and after embedding a resin serving as a base material later, or simultaneously, a metal foil or a wiring member is connected. ing. In these methods, there has been proposed a method of applying a conductive resin, gold plating, solder plating, or the like to a conductive projection head in order to improve connection reliability. In addition, the present inventors have developed a semiconductor package in which a bump formed by etching a metal foil is embedded with a resin and used for wiring for interlayer connection (for example, see Patent Document 1). If the resin of the package substrate used for this is brought into a semi-cured state (B-stage state), the conductive projection surface of the substrate and the metal foil or the wiring member can be easily pressed and heated together. A wiring member connected between layers can be manufactured. However, in this method, since the connection between the conductive protrusion and the metal foil or the wiring member is merely abutted and the connection is maintained by the adhesive force of the surrounding resin, there is a concern about long-term reliability. After applying the conductive resin to the conductive projection head exposed from the insulating resin to improve the reliability, there is also a connection method, but since the bonding surface has irregularities, the adhesion becomes uneven, The tension deteriorates the flatness in the fitted state. In order to improve these, it is necessary to use a resin having high fluidity at the time of heating and pressurizing, and there is a great limitation in selecting the resin. Also, when the fluidity is high, it tends to shift and the thickness tends to be uneven.
[0005]
[Non-patent document 1]
NIKKEI MATERIALS & TECHNOLOGY 94.4, No. 140, p18-19
[Non-patent document 2]
Small Flip-Chip-Like Package CSP; The Second VLSI Packaging Workshop of Japan, p46-50, 1994
[Patent Document 1]
JP-A-2002-043467
[0006]
[Problems to be solved by the invention]
SUMMARY OF THE INVENTION An object of the present invention is to provide a structure and a manufacturing method for an interlayer connection member in which conductive protrusions are formed in advance on a metal foil and a resin serving as a base material is buried later, thereby improving the reliability of interlayer connection.
[0007]
[Means for Solving the Problems]
In order to solve the above problem, the present inventors are in a state in which the conductive resin is applied to the conductive projection head and embedded in the resin, and almost the conductive resin is exposed on the insulating resin surface. The present inventors have devised an interlayer connecting member having no and almost no depression and a manufacturing method thereof.
[0008]
That is, the present invention provides the following intermediate wiring member for lamination, a wiring board using the same, and a method for manufacturing the same.
(1) (1) a wiring member having a conductive layer and a plurality of conductive protrusions protruding on one surface of the conductive layer; (2) a conductive resin applied on a tip end surface of the conductive protrusion of the wiring member; (3) an intermediate wiring member for lamination having an insulating resin in which a front end surface of a conductive resin is exposed and a conductive protrusion and a conductive resin are embedded on a surface side of the wiring member having the conductive protrusion, The conductive resin and the insulating resin have no fluidity but are in a semi-cured state before reaching a completely cured state, and the insulating resin surface and the exposed surface of the conductive resin exposed on the insulating resin surface are flat and flat. The intermediate wiring member A for lamination forming the above.
(2) In the wiring member, the conductor layer is at least a third metal layer, and the conductive protrusions are two layers of a second metal layer on the conductor layer and a first metal layer on the second metal layer. Or the wiring member is such that the conductor layer is at least a third metal layer and a second metal layer on the third metal layer, and the conductive protrusion is a second metal layer of the conductor layer. The intermediate wiring member A for lamination according to (1), wherein the intermediate wiring member A is made of a first metal on a layer.
[0009]
(3) The intermediate wiring for lamination according to (2), wherein the first metal and the second metal are metals having different etching conditions, and the second metal and the third metal are metals having different etching conditions. Member A.
(4) The first resin in a semi-cured state, comprising at least two layers of a core layer made of a first insulating resin in contact with the conductor layer and a surface layer made of a second insulation resin on the conductor layer. The intermediate wiring member for lamination A according to any one of (1) to (3), wherein the insulating resin is harder than the second insulating resin in a semi-cured state.
(5) The lamination intermediate wiring member A according to any one of (1) to (4), wherein the area of the exposed surface of the conductive resin exposed on the insulating resin surface is smaller than the area of the tip end surface of the conductive protrusion.
[0010]
(6) (1) a wiring member having a conductive layer and a plurality of conductive protrusions protruding on one surface of the conductive layer; and (2) a conductive protrusion is buried on the surface of the wiring member having the conductive protrusion. An insulating resin forming a flattened insulating resin surface except that the surface has a concave portion whose bottom is the front end surface of the conductive protrusion; and (3) a front end of the conductive protrusion. An intermediate wiring member for lamination having a conductive resin applied on a surface, wherein the conductive resin and the insulating resin have no fluidity but are in a semi-cured state before reaching a completely cured state. Member B.
(7) The wiring member, wherein the conductor layer is made of a third metal, and the conductive projection is made of two layers of a second metal layer on the conductor layer and a first metal layer on the second metal layer. Alternatively, the wiring member is such that the conductor layer is composed of a third metal layer and a second metal layer on the third metal layer, and the conductive protrusion is formed on the second metal layer of the conductor layer. The intermediate wiring member B for lamination according to (6), comprising one metal.
[0011]
(8) The intermediate wiring for lamination according to (7), wherein the first metal and the second metal are metals having different etching conditions, and the second metal and the third metal are metals having different etching conditions. Member B.
(9) The first resin in a semi-cured state, comprising at least two layers of a core layer made of the first insulating resin in contact with the conductor layer and a surface layer made of the second insulation resin on the conductor layer. The lamination intermediate wiring member B according to any one of (6) to (8), wherein the insulating resin is harder than the second insulating resin in a semi-cured state.
[0012]
(10) The flatness of the intermediate wiring member B for lamination according to any one of (1) to (5) or the flattening surface of the intermediate wiring member B for lamination according to any one of (6) to (9). Forming a conductor circuit bonded by heat and pressure on the insulating resin surface, curing the semi-cured insulating resin and semi-cured conductive resin, and forming the circuit by partial etching of the conductor layer Wiring board.
(11) The wiring board according to (10), which is used as a substrate for a semiconductor package.
[0013]
(12) a conductive resin application step of applying a conductive resin to a tip surface of a conductive protrusion of a wiring member having a conductive layer and a plurality of conductive protrusions protruding on one surface of the conductive layer; A conductive resin drying step of drying to a semi-cured state before the fluidity is lost but reaching a completely cured state, the insulating resin in a fluid varnish state before curing is applied to the surface of the wiring member having the conductive protrusions In addition, by printing, an insulating resin printing step of applying a conductive protrusion and a conductive resin in a semi-cured state to a thickness embedded in the insulating resin, the printed insulating resin loses fluidity but before reaching a completely cured state, An insulating resin drying step of drying to a semi-cured state, and polishing the semi-cured insulating resin to expose the semi-cured conductive resin, and flatten the surface of the insulating resin including the exposed surface of the conductive resin. Polishing process Method for manufacturing a laminated intermediate wiring member A according to (1).
(13) As the wiring member, a multilayer metal foil having at least three layers of a first metal layer made of a first metal, a second metal layer made of a second metal, and a third metal layer made of a third metal in this order is used. Removing the first metal layer until the second metal layer is partially exposed, thereby forming a conductor layer including the second metal layer and the third metal layer and a plurality of conductive protrusions including the first metal. Or by using the multilayer metal foil and removing the first metal layer and the second metal layer partially until the third metal layer is exposed, thereby forming a conductor comprising the third metal layer. The method for manufacturing the intermediate wiring member A for lamination according to (12), wherein the plurality of conductive protrusions are formed by forming a plurality of conductive protrusions including a layer, a second metal layer, and a third metal layer on the second metal layer. .
[0014]
(14) The first metal and the second metal are metals having different etching conditions, the second metal and the third metal are metals having different etching conditions, and the first metal layer is partially removed. (14), wherein the first metal layer and the second metal layer are partially removed by sequentially etching them under different etching conditions. .
(15) In the insulating resin printing step, at least two types of insulating resins, a first insulating resin and a second insulating resin, are used as the insulating resin, and the first insulating resin is printed on the conductor layer to form a core layer; Thereafter, a second insulating resin is printed to form a surface layer, and the first insulating resin in the semi-cured state is harder than the second insulating resin in the semi-cured state (12) to (14). The method for producing an intermediate wiring member A for lamination according to any one of the above.
[0015]
(16) Printing the insulating resin in a fluid varnish state before curing on the surface having the conductive protrusions of the wiring member having the conductive layer and the plurality of conductive protrusions protruding on one surface of the conductive layer. Thereby, an insulating resin printing step of applying the conductive protrusions to a thickness embedded in the insulating resin, an insulating resin drying step of drying the printed insulating resin to a semi-cured state before losing fluidity but before reaching a completely cured state, Polishing the semi-cured insulating resin to expose the tip surface of the conductive protrusion, and flatten the semi-cured insulating resin surface to form a planarized insulating resin surface; A half-etching step of performing half-etching by etching from the tip end surface exposing the protrusion, a conductive resin applying step of applying a conductive resin to the tip end surface of the half-etched conductive protrusion, and coating The conductive resin, but not the fluidity before reaching the full cure conditions, method for manufacturing a laminated intermediate wiring member B according to a conductive resin drying step of drying to a semi-cured state (6).
[0016]
(17) As the wiring member, a multilayer metal foil having at least three layers of a first metal layer made of a first metal, a second metal layer made of a second metal, and a third metal layer made of a third metal in this order is used. Removing the first metal layer until the second metal layer is partially exposed, thereby forming a conductor layer including the second metal layer and the third metal layer and a plurality of conductive protrusions including the first metal. Or by using the multilayer metal foil and removing the first metal layer and the second metal layer partially until the third metal layer is exposed, thereby forming a conductor layer comprising the third metal layer. And a method of manufacturing the intermediate wiring member B for lamination according to (16), wherein the plurality of conductive protrusions are formed by forming a plurality of conductive protrusions including a second metal layer and a first metal layer on the second metal layer.
(18) The first metal and the second metal are metals having different etching conditions from each other, the second metal and the third metal are metals having different etching conditions from each other, and the first metal layer is partially removed. (17) The method for manufacturing the intermediate wiring member B for lamination according to (17), wherein the first metal layer and the second metal layer are partially removed by etching sequentially under different etching conditions. .
[0017]
(19) In the insulating resin printing step, at least two types of insulating resins, a first insulating resin and a second insulating resin, are used as the insulating resin, and the first insulating resin is printed on the conductor layer to form a core layer; Thereafter, a surface layer is formed by printing a second insulating resin, and the first insulating resin in the semi-cured state is harder than the second insulating resin in the semi-cured state (16) to (18). The method for producing an intermediate wiring member B for lamination according to any one of the above.
(20) The flatness of the intermediate wiring member B for lamination according to any one of (1) to (5) or the flattening surface of the intermediate wiring member B for lamination according to any one of (6) to (9). Forming a conductor circuit bonded by heating and pressing on the surface of the insulated insulating resin, curing the semi-cured insulating resin and the semi-cured conductive resin, and forming a circuit by partial etching of the conductor layer. Manufacturing method of wiring board including.
(21) The method for manufacturing a wiring board according to (20), wherein the wiring board is a substrate for a semiconductor package.
[0018]
(22) A metal foil is placed on the flattened surface of the intermediate wiring member for lamination A according to any one of (1) to (5), and the metal foil and the intermediate wiring for lamination are applied by applying pressure and heat. Bonding the member A and curing the semi-cured insulating resin and the semi-cured conductive resin; and forming a circuit by partially etching the metal foil bonded to the conductor layer of the intermediate wiring member A for lamination, respectively. A method for manufacturing a wiring board, comprising the steps of:
(23) The method for manufacturing a wiring board according to (22), wherein the wiring board is a substrate for a semiconductor package.
(24) A metal foil is placed on the flattening insulating resin surface of the intermediate wiring member B for lamination according to any one of (6) to (9), and the metal foil and the metal foil are laminated by applying pressure and heat. A step of bonding the intermediate wiring member B and curing the semi-cured insulating resin and the semi-cured conductive resin, and partially etching the metal foil bonded to the conductor layer of the intermediate wiring member B for lamination, respectively. A method for manufacturing a wiring board having a step of forming a circuit.
(25) The method for manufacturing a wiring board according to (24), wherein the wiring board is a substrate for a semiconductor package.
[0019]
(26) A metal foil is placed on the flattened surface of the intermediate wiring member A for lamination according to any one of (1) to (5), and the metal foil and the intermediate wiring member A for lamination are applied by applying pressure and heat. And curing the semi-cured insulating resin and the semi-cured conductive resin, and partially etching the conductor layer of the intermediate wiring member A for lamination and / or the bonded metal foil to form a circuit. In the step of producing the wiring member C, the intermediate wiring member A ′ for lamination and the wiring member C according to any one of (1) to (5) are connected to the flattening surface of the intermediate wiring member A ′ for lamination. The wiring of the member C and the intermediate wiring member A 'for lamination are adhered by applying pressure and heat, and the insulating resin in a semi-cured state of the intermediate wiring member A' for lamination is applied by applying pressure and heat. Curing the conductive resin in a semi-cured state, and conducting the intermediate wiring member A 'for lamination. Layer and, the adhered conductive layer or metal foil is not the circuit formation of the wiring member C, a method for manufacturing a multilayer wiring board comprising a step of forming a circuit by partial etching.
(27) The manufacturing method according to (26), wherein the multilayer wiring board is a multilayer board for a semiconductor package.
[0020]
(28) A metal foil is placed on the flattening insulating resin surface of the intermediate wiring member B for lamination according to any one of (6) to (9), and pressure and heat are applied to the metal foil and the intermediate wiring for lamination. A step of bonding the member B and curing the semi-cured insulating resin and the semi-cured conductive resin, and forming a circuit by partially etching the conductive layer of the intermediate wiring member B for lamination and / or the bonded metal foil And forming the wiring member D by performing the above-mentioned steps. The intermediate wiring member B ′ for lamination and the wiring member D according to any one of (6) to (9) are flattened and insulated from the intermediate wiring member B ′ for lamination. Laminate so that the resin surface and the circuit of the wiring member D are in contact with each other, apply pressure and heat to bond the wiring member D and the intermediate wiring member B 'for lamination, and semi-harden the intermediate wiring member B' for lamination. Curing the insulating resin in the state and the conductive resin in the semi-cured state, A conductive layer member B ', and adhered conductive layer or metal foil is not the circuit formation of the wiring member D, manufacturing method for a multilayer wiring board comprising a step of forming a circuit by partial etching.
(29) The method according to (28), wherein the multilayer wiring board is a multilayer board for a semiconductor package.
[0021]
(30) At least three layers of a first metal layer made of a first metal, a second metal layer made of a second metal, and a third metal layer made of a third metal are arranged in this order, and the first metal and the second metal Is a metal having different etching conditions from each other, and a second metal and a third metal are provided with a multilayer metal foil having different etching conditions from each other, and the first metal layer is partially formed until the second metal layer is exposed. To form a plurality of conductive protrusions made of the first metal on the exposed surface of the second metal layer, or to expose the first metal layer and the second metal layer in this order to expose the third metal layer. Forming a plurality of conductive protrusions composed of two layers of a first metal layer and a second metal layer on the exposed surface of the third metal layer by partially etching each of the conductive metal layers until the conductive protrusions are formed. The hard surface is exposed on the exposed surface of the second metal layer or the exposed surface of the third metal layer. The printing process of applying the insulating resin in the previous fluid varnish state by printing to a thickness at which the conductive protrusions are embedded in the insulating resin, and drying the printed insulating resin to a semi-cured state or a completely cured state. Drying or curing step of drying or curing, polishing the semi-cured or cured insulating resin, exposing the tip surface of the conductive projection on the insulating resin surface, and polishing step of flattening the insulating resin surface, etching Forming a circuit surface by partially etching the unexposed second metal layer and the third metal layer or the unetched third metal layer to form a circuit, thereby forming a wiring member E; The intermediate wiring member A for lamination according to any one of 1) to (5) is laminated so that the circuit surface of the wiring member E and the flattened surface of the intermediate wiring member A for lamination are in contact with each other, and pressure and heat are reduced. Bonding the wiring member E and the intermediate wiring member A for lamination and curing the semi-cured insulating resin and the semi-cured conductive resin, and removing the conductive layer of the intermediate wiring member A for lamination. A method for manufacturing a multilayer wiring board having a step of forming a circuit by partial etching.
(31) The manufacturing method according to (30), wherein the multilayer wiring board is a multilayer board for a semiconductor package.
[0022]
(32) At least three layers of a first metal layer made of a first metal, a second metal layer made of a second metal, and a third metal layer made of a third metal in this order, and the first metal and the second metal Is a metal having different etching conditions from each other, and a second metal and a third metal are provided with a multilayer metal foil having different etching conditions from each other, and the first metal layer is partially formed until the second metal layer is exposed. To form a plurality of conductive protrusions made of the first metal on the exposed surface of the second metal layer, or to expose the first metal layer and the second metal layer in this order to expose the third metal layer. Forming a plurality of conductive protrusions composed of two layers of a first metal layer and a second metal layer on the exposed surface of the third metal layer by partially etching each of the conductive metal layers until the conductive protrusions are formed. The hard surface is exposed on the exposed surface of the second metal layer or the exposed surface of the third metal layer. The printing process of applying the insulating resin in the previous fluid varnish state by printing to a thickness at which the conductive protrusions are embedded in the insulating resin, and drying the printed insulating resin to a semi-cured state or a completely cured state. Drying or curing step of drying or curing, polishing the semi-cured or cured insulating resin, exposing the tip surface of the conductive projection on the insulating resin surface, and polishing step of flattening the insulating resin surface, etching Forming a circuit surface by partially etching the unexposed second metal layer and the third metal layer or the unetched third metal layer to form a circuit, thereby forming a wiring member E; 6) to (9), the lamination intermediate wiring member B is laminated so that the circuit surface of the wiring member E and the flattening insulating resin surface of the lamination intermediate wiring member B are in contact with each other. Heat and heat to bond the wiring member E and the intermediate wiring member B for lamination and to cure the semi-cured insulating resin and the conductive resin in the semi-cured state; A method for manufacturing a multilayer wiring board, comprising a step of forming a circuit by partially etching a body layer.
(33) The method according to (32), wherein the multilayer wiring board is a multilayer board for a semiconductor package.
[0023]
(34) A circuit is formed by screen-printing a conductive resin on the flattened surface of the intermediate wiring member A for lamination according to any one of (1) to (5), and the fluidity is lost but a completely cured state And drying the intermediate wiring member A for lamination and the intermediate wiring member A 'for lamination according to any one of (1) to (5). The laminating intermediate wiring member A and the laminating intermediate wiring member A 'are bonded by applying pressure and heat so that the circuit-formed surface of A and the flattening surface of the laminating intermediate wiring member A' are in contact with each other. Curing the semi-cured insulating resin and the semi-cured conductive paste, and partially etching the conductor layer of the lamination intermediate wiring member A and the lamination intermediate wiring member A ′. A method for manufacturing a multilayer wiring board having a step of forming a circuit.
(35) The method according to (34), wherein the multilayer wiring board is a multilayer board for a semiconductor package.
[0024]
(36) A circuit is formed by screen-printing a conductive resin on the flattening insulating resin surface of the intermediate wiring member for lamination B according to any one of (6) to (9), and the fluidity is lost but complete. A step of drying to a semi-cured state before reaching a cured state, the step of drying the laminated intermediate wiring member B and another laminated intermediate wiring member B ′ according to any one of (6) to (9), The wiring member B is laminated so that the circuit-formed surface of the wiring member B and the flattening insulating resin surface of the laminating intermediate wiring member B ′ are in contact with each other, and pressure and heat are applied to the laminating intermediate wiring member B and the laminating intermediate wiring member B. And curing the semi-cured insulating resin and the semi-cured conductive paste; and bonding the conductive layer of the intermediate wiring member B for lamination and the conductive layer of the intermediate wiring member B 'for lamination. Method of manufacturing multilayer wiring board including step of forming circuit by partial etching .
(37) The manufacturing method according to (36), wherein the multilayer wiring board is a multilayer board for a semiconductor package.
[0025]
BEST MODE FOR CARRYING OUT THE INVENTION
The intermediate wiring member A for lamination according to the present invention includes: (1) a wiring member having a conductive layer and a plurality of conductive protrusions protruding on one surface of the conductive layer; and (2) a top surface of the conductive protrusion of the wiring member. (3) A wiring member having an electrically conductive resin, and (3) an insulating resin in which the front end surface of the conductive resin is exposed and the conductive protrusion and the conductive resin are embedded on the surface of the wiring member having the conductive protrusion. The conductive resin and the insulating resin have no fluidity but are in a semi-cured state before reaching a completely cured state, and the insulating resin surface and the exposed surface of the conductive resin exposed on the insulating resin surface are flat. A planarized surface is formed.
[0026]
The intermediate wiring member B for lamination of the present invention includes (1) a wiring member having a conductive layer and a plurality of conductive protrusions protruding on one surface of the conductive layer, and (2) a surface of the wiring member having the conductive protrusion. On the side, an insulating resin that embeds the conductive protrusions, the insulating resin forming a flattened insulating resin surface except that the surface has a concave portion whose bottom is the front end surface of the conductive protrusions, And (3) having a conductive resin applied on the tip end surface of the conductive protrusion, wherein the conductive resin and the insulating resin have no fluidity but are in a semi-cured state before reaching a completely cured state. is there. The conductive resin is applied on the tip surface of the conductive protrusion in the concave portion of the flattening insulating resin surface. In the intermediate wiring member B for lamination, the surface of the insulating resin may be flattened except for the concave portion, and the upper surface of the conductive resin is not necessarily on the same plane as the flat portion of the flattened surface of the insulating resin. Is also good. Further, the conductive resin does not necessarily have to be completely buried with the insulating resin except for the end surface. However, the amount of the conductive resin applied in each concave portion is preferably the same or substantially the same as the volume of the concave portion, and is usually preferably 80 to 130% by volume of the concave portion.
[0027]
The insulating resin and conductive resin of the intermediate wiring members A and B for lamination are in a semi-cured state, and the surface is flat or almost flat. Therefore, when laminating a metal foil or other wiring members on the flattened surface or the flattened insulating resin surface, it is possible to easily and uniformly adhere by heat and pressure treatment. In addition, the conductive protrusions are bonded to the metal foil and the wiring member by a conductive resin as well as merely abutting. Therefore, the reliability of the interlayer connection is significantly improved.
In the present invention, the term “flat” means that the surface has a flatness of 10 μm or less, or ± 10% or less with respect to the thickness of the insulating resin.
[0028]
The lamination intermediate wiring member A can be suitably manufactured, for example, by the method for manufacturing a lamination intermediate wiring member A of the present invention. First, a conductive resin is applied to a tip surface of a conductive protrusion of a wiring member having a conductive layer and a plurality of conductive protrusions protruding on one surface of the conductive layer (conductive resin coating step). Next, the conductive resin applied to the tip end surface of the conductive protrusion is dried to a semi-cured state before the fluidity is lost but before a completely cured state is reached (conductive resin drying step). Next, the insulating resin in a fluid varnish state before curing is printed on the surface of the wiring member having the conductive protrusions by printing to a thickness at which the conductive protrusions and the semi-cured conductive resin are embedded in the insulating resin. Apply (insulating resin printing process). Next, the printed insulating resin is dried to a semi-cured state before reaching a completely cured state although the fluidity is lost (insulating resin drying step). Thereafter, the semi-cured insulating resin is polished to expose the semi-cured conductive resin, and the surface of the insulating resin including the exposed surface of the conductive resin is flattened (polishing step) to form a laminate. An intermediate wiring member A is obtained.
[0029]
The lamination intermediate wiring member B can be suitably manufactured, for example, by the method for manufacturing a lamination intermediate wiring member B of the present invention. First, an insulating resin in a fluid varnish state before curing is printed on a surface having conductive protrusions of a wiring member having a plurality of conductive protrusions protruding on one surface of the conductive layer and the conductive layer by printing. Then, the conductive protrusions are applied to a thickness to be embedded in the insulating resin (insulating resin printing step). Next, the printed insulating resin is dried to a semi-cured state before it reaches a completely cured state although the fluidity is lost (insulating resin drying step). Next, the tip of the conductive protrusion is exposed by polishing the semi-cured insulating resin, and the semi-cured insulating resin surface is flattened to form a flattened insulating resin surface (polishing step). Next, half etching is performed by etching the exposed conductive protrusions from the exposed front end surface (half etching step). In this step, a concave portion is formed on the flattening insulating resin surface, the concave portion having the tip end surface of the conductive protrusion subjected to the herb etching as a bottom. Next, a conductive resin is applied to the tip surface of the half-etched conductive protrusion (conductive resin application step). Next, the applied conductive resin is dried to a semi-cured state before the fluidity is lost but reaches a completely cured state (conductive resin drying step), thereby obtaining the intermediate wiring member B for lamination.
[0030]
Examples of the wiring member having a plurality of conductive protrusions protruding on one surface of the conductive layer and the conductive layer used in the present invention include the following 1 and 2.
1. Metal foil having conductive protrusions on its surface. Such a metal foil has, for example, at least a third metal layer as a conductor layer, and as a plurality of conductive protrusions on the surface of the conductor layer, a second metal layer and a second metal layer on the second metal layer. One having a plurality of protrusions composed of two layers of one metal, or a composite layer composed of at least a third metal layer as a conductor layer, and a second metal layer on the third metal layer; Examples of the plurality of conductive protrusions on the surface of the body layer include those having a plurality of protrusions made of the first metal on the layer of the second metal.
2. A wiring member made of a conductor having conductive protrusions and an insulating resin. For example, a wiring member having an insulating resin layer, conductive layers connected to each other on both surfaces of the insulating resin layer, and conductive protrusions on the conductive layer on at least one surface of the insulating resin layer. In this case, usually, a conductor layer having at least a conductive protrusion forms a circuit.
[0031]
The metal foil having conductive protrusions on the surface includes, for example, at least three layers of a first metal layer made of a first metal, a second metal layer made of a second metal, and a third metal layer made of a third metal. The first metal layer is partially removed until the second metal layer is exposed by using a multilayer metal foil having a first metal layer and a second metal layer and a conductor layer including the second metal layer and the third metal layer. The first metal layer and the second metal layer are partially removed until the third metal layer is exposed by using the multilayer metal foil. It can be manufactured by forming a plurality of conductive protrusions including a conductor layer formed of three metal layers, a second metal layer, and a first metal layer on the second metal layer. For example, as the multi-layer metal foil, a first metal and a second metal having different etching conditions from each other and a second metal and a third metal having different etching conditions from each other are used. Partial removal of the metal layer is performed by etching, or partial removal of the first metal layer and the second metal layer is performed by sequentially etching under different etching conditions. More specifically, a three-layer metal foil in which the first and third metal layers are different from the second metal layer in etching conditions is formed by etching a first metal layer into a plurality of metal foils using a dry film resist. The first metal layer may be formed into a plurality of columnar bumps by etching using a dry film resist, or the second metal layer may be formed into a lower portion of the columnar bumps. Except for the above, etching removal is performed until the third metal layer is exposed to form conductive projections.
[0032]
In the above-mentioned multilayer metal foil, as the first metal layer, for example, one selected from copper, a copper alloy, an iron / nickel alloy, or the like can be used. As the second metal layer, for example, when the first metal layer is copper or a copper alloy, nickel, a nickel alloy, titanium, chromium, tin, zinc, gold, or the like can be used. In the case of an iron-nickel alloy, titanium, chromium, tin, or the like can be used. As the third metal layer, for example, when the second metal layer is nickel, a nickel alloy, titanium, chromium, tin, zinc, gold, or the like, copper or a copper alloy can be used. Is titanium, chromium, tin or the like, an iron-nickel alloy or the like can be used. Here, the metal layers having different etching conditions mean a metal layer having a high erosion property and a metal layer having a low erosion property with respect to one kind of etching solution, or a metal having an erosion property with respect to different etching solutions.
Examples of the wiring member made of the conductor having the conductive protrusions and the insulating resin include, for example, a metal foil having the conductive protrusions on the surface, a resin layer formed by exposing the front end surfaces of the conductive protrusions. On the resin layer forming surface, the above-mentioned three-layer metal foil is further heat-pressed, and then the first metal layer or the first metal layer and the second metal layer are similarly etched into columnar bumps to form conductive protrusions. . In addition, the surface of a general double-sided wiring board, printed on a conductive resin such as silver paste to form conductive protrusions, using a plating resist or the like, also includes those formed metal protrusions by plating deposition .
[0033]
In the case of a multilayer metal foil having at least three layers of a first metal layer, a second metal layer, and a third metal layer, the thickness of the first metal layer forming the columnar bump is preferably 12 to 100 μm, and more preferably 100 μm. If it exceeds, the etching accuracy when forming a metal pillar or an external connection terminal is low, and there is a possibility that formation of a fine pattern may be difficult, and if it is less than 12 μm, the strength of the conductive projections may be insufficient or In addition, the insulating property of the insulating resin may be reduced. More preferably, it is 18 to 70 μm. The thickness of the second metal layer is preferably 0.05 to 50 μm, and if it exceeds 50 μm, the etching accuracy at the time of circuit formation is low, and it may be difficult to form a fine pattern. If it is less than 3, the third metal layer may be eroded due to pits or chips generated in the second metal layer when etching the first metal layer. More preferably, it is 0.1 to 35 μm. The thickness of the third metal layer is preferably 1 to 50 μm, and if it exceeds 50 μm, the etching accuracy may be reduced at the time of forming a circuit, and it may be difficult to form a fine pattern. Then, when the first metal layer is etched, the third metal layer may be eroded due to pits or chips generated in the second metal layer. In the case where a circuit is formed on the third metal layer and laminated on the third metal layer, the thinner the third metal layer is, the better the embedding property between circuits is. More preferably, it is 5 to 12 μm.
[0034]
The shape of the conductive projection is not particularly limited as long as it is a solid columnar shape, and is usually a column having a radius of 10 to 750 μm, a square having a side of 20 μm to 1000 μm, or the like.
[0035]
The insulating resin used in the intermediate wiring members A and B for lamination and the manufacturing method thereof has fluidity at the time of coating (at this time, the coating environment may be room temperature, or the insulating resin may be heated to obtain fluidity. After application), it becomes a state without fluidity that can be polished by drying etc. after application, and it can be re-adhered by applying pressure, heating, or applying reactive groups at the time of lamination for later lamination Any resin may be used. Examples include thermosetting resins such as polyimide resin, polyamide imide resin, silicone-modified polyamide imide resin, silicone resin, phenol resin, bismaleimide triazine resin, epoxy resin, acrylic resin, polyphenylene sulfide resin, photosensitive polyimide resin, acrylic Examples include epoxy resins, thermoplastic elastomers such as ethylene, propylene, styrene, and butadiene, and liquid crystal polymers. Further, those obtained by blending organic particles or inorganic particles with these resins can also be used. Examples of the organic particles that can be blended with the resin include cured products of the aforementioned resins, and examples of the inorganic particles include alumina particles, silicon dioxide (silica), and glass fibers. The organic or inorganic particles preferably have an average particle size of 0.1 to 20 μm. The purpose of blending organic or inorganic particles in the insulating resin is to reduce curing shrinkage and adjust the thermal expansion coefficient. The curing shrinkage amount can be reduced by increasing the blending amount of the particles. However, since the amount of the resin decreases relatively and the adhesive strength decreases, the blending amount is desirably 90% by weight or less based on the total amount of the insulating resin. To adjust the thermal expansion coefficient, inorganic particles are often blended. The blending amount is adjusted to match the expansion coefficient of the member to be bonded. However, if the blending amount is increased, the adhesive strength is reduced, so the blending amount is desirably 90% by weight or less based on the total amount of the insulating resin. For example, when the adhesive member is made of silica particles and made of copper, the compounding amount is desirably 40 to 80% by weight based on the total amount of the insulating resin.
[0036]
In the insulating resin printing step of the method for manufacturing the intermediate wiring members A and B for lamination, the insulating resin in a fluid varnish state before curing is applied to the surface of the wiring member having the conductive protrusions by the intermediate wiring member A for lamination. At the time of manufacturing, the conductive protrusions and the semi-cured conductive resin are applied by printing to a thickness embedded with the insulating resin, and at the time of manufacturing the lamination intermediate wiring member B, the conductive protrusions are applied by printing to a thickness embedded with the insulating resin. The insulating resin in the fluid varnish state preferably has a viscosity of 3 to 70 Pa · s during printing. As a printing method, a mesh screen mask, a screen printing method using a metal mask or the like, and a method of applying an insulating resin to a uniform thickness with a squeegee, a blade, or the like directly on the wiring member with a gap or a gap, And a method of applying an insulating resin onto a wiring member after applying the resin to a drum or a board. Further, a method of performing these operations under vacuum is also effective for eliminating unfilled portions.
[0037]
The intermediate wiring members A and B for lamination and the conductive resin used in the method for producing the same have fluidity during application similarly to the insulating resin (the application environment may be room temperature, or the conductive resin may have fluidity). May be heated so that it can be polished by drying after application, etc., and at the time of subsequent application for lamination, pressurization, heating, application of reactive groups, etc. Any conductive resin that can be re-adhered can be used. Examples of the binder used for the conductive resin include a polyimide resin, a polyamideimide resin, a silicone-modified polyamideimide resin, a silicone resin, a phenol resin, a bismaleimide triazine resin, an epoxy resin, a thermosetting resin such as an acrylic resin, Examples include polyphenylene sulfide resin, photosensitive polyimide resin, acrylic epoxy resin, thermoplastic elastomers such as ethylene, propylene, styrene, and butadiene, and liquid crystal polymers. Examples of conductive particles to be added to these resins include gold particles, silver particles, copper particles, solder particles, carbon particles, nickel particles, aluminum particles, titanium particles, iron particles, and the like, mixed particles of these particles, There are alloy particles of these metals and coatings of these metals and alloys on inorganic or organic particles. These particles preferably have an average particle size of 0.5 to 20 μm. The amount of the conductive particles is generally required to be 80% by weight or more in order to obtain sufficient conductivity. However, in the present invention, the conductive particles are heated and pressed at the time of lamination with a metal foil or the like. It is sufficient that conductivity between the metal protrusions and the metal foil to be laminated is obtained, and there is no need to have conductivity in a dry state and a state cured without pressing. Therefore, it is possible to obtain conductivity after curing under heat and pressure with a smaller amount of compounding. That is, since the resin ratio can be increased, the adhesiveness can be further increased. For example, when using metal particles of a size equal to or greater than the thickness of the conductive resin after lamination and bonding, the metal particles are directly in contact with the conductive protrusions and the metal foil by heating and pressing. The joint can be obtained with several metal particles (for one joint). Further, when two or more types of metal particles are blended, by making the heating temperature during lamination and the melting temperature of one type of metal particles equal, metal bonding between the metal particles proceeds during pressurization and heating, and the conductivity is increased. Since metal bonding with the conductive protrusions and the metal foil is also performed, conductivity can be obtained with a smaller blending amount. Therefore, the amount of the conductive particles is preferably 30 to 90% by weight, more preferably 40 to 80% by weight, based on the total amount of the conductive particles and the binder.
[0038]
In the present specification, the semi-cured state of the insulating resin and the conductive resin refers to a state in which fluidity has been lost and the resin has been cured to a polished state and has not been completely cured. The thermosetting resin is called a B-stage state, and generally varies depending on the resin, but generally has a curing rate of 30 to 80%. This curing rate can be measured by DSC (differential scanning calorimetry). When the insulating resin is a thermosetting resin, the insulating resin is dried to a semi-cured state by heating. When the insulating resin is returned to the room temperature (5 to 35 ° C.) at the time of polishing, there is no fluidity and an external force is applied. When the external pressure is removed, elastic deformation or plastic deformation occurs, the elastic deformation returns to its original state, and when plastic deformation occurs, the deformed state is maintained.
In the case of a solvent-diluted type thermoplastic material, a semi-cured state can be obtained by appropriately removing the solvent component. As a method of removing the solvent, there is a method of heating or reducing the pressure. Like a thermosetting resin, a state that can be polished means that there is no fluidity, elastic deformation or plastic deformation occurs when an external force is applied, and when external pressure is removed, the state returns to the original state in the case of elastic deformation, plastic deformation If so, the state is such that the deformed state is maintained.
[0039]
When a photosensitive resin such as a photosensitive polyimide is used, the amount of curing can be controlled by the amount of ultraviolet irradiation. In the case of a photosensitive resin, the upper portion of the conductive protrusion is prevented from being exposed to ultraviolet light by masking or the like, the amount of ultraviolet light irradiation is reduced from the amount of ultraviolet light irradiation of portions other than the conductive protrusion portion, and the upper portion of the conductive protrusion is not exposed to other light. By setting the part in an uncured state, the upper portion of the conductive protrusion can be polished more concentratedly, and the polishing efficiency can be increased. Further, if the photosensitive resin is of a type that can remove the exposed portion and the other portion with a chemical solution, by changing the amount of ultraviolet irradiation on the conductive protrusion and the other portion, only the resin on the conductive protrusion can be removed. It can be removed with a chemical solution, and the top of the conductive projection can be caught without polishing or with slight polishing.
[0040]
In the insulating resin printing process, a single insulating resin layer may be formed using only one kind of insulating resin, or two or more kinds of insulating resins, resins having the same composition, and a filling ratio of a filler or the like may be changed. These may be used to form a multilayer insulating resin layer. By changing the composition of the resin in each layer, the type of resin, the thickness, or the number of layers, it is possible to control the thickness, the interlayer displacement, and the overall amount of warpage when the wiring member is multilayered. In the case of forming a multilayer insulating resin layer, it is important that the resin of the first layer be a layer having good adhesiveness by selecting the resin according to the type and surface condition of the member. It is preferable that the resin layer is in a state of being hard and hard to flow during lamination. On the other hand, the resin of the surface layer that adheres to the wiring member has high adhesiveness, and it is preferable to use a resin that has fluidity during adhesion.
[0041]
For example, on the surface of the wiring member having the conductive protrusions, a first insulating resin which is in a fluid varnish state, has good adhesion, and hardly flows when a different wiring member is bonded in a semi-cured state, is printed, Although the fluidity is lost, it is dried to a semi-cured state before complete curing, and then has a different composition from the first insulating resin and is in a fluid varnish state. When a soft insulating resin which flows easily when the wiring members are bonded is printed, the fluidity is lost, but by drying to a semi-cured state before complete curing, the first insulating resin core layer and the second insulating resin are dried. A multi-layer insulating resin layer composed of at least two surface layers of the insulating resin is formed to a thickness such that the conductive protrusions or the conductive protrusions and the conductive resin are embedded with the insulating resin. This makes it possible to prevent deformation of the base material during pressurization with the resin layer serving as the core layer in the central portion, and to improve embedding and adhesion due to the fluid resin layer on the surface. As a combination of the first insulating resin for the relatively soft surface layer and the second insulating resin for the relatively hard core layer, for example, a resin is used as the first insulating resin, and 100 parts by weight of the resin is used as the second insulating resin. And a combination using a composition in which 40 to 90 parts by weight, preferably 50 to 80 parts by weight of an inorganic or organic filler is blended. Further, the thickness of the core layer and the surface layer is preferably 10 μm or more in order to obtain sufficient embedding and adhesiveness as the surface layer, and the thickness of the core layer is 50 to 50% with respect to the entire insulating resin thickness. Desirably, it occupies 90%.
[0042]
In the conductive resin application step of the manufacturing method of the lamination intermediate wiring members A and B, as a method of applying a conductive resin on the tip surface of the conductive protrusion of the wiring member, first, the viscosity of the conductive resin is set to 3 at the time of printing. The pressure is preferably up to 70 Pa · s. As a printing method, a screen printing method using a mesh screen mask, a metal mask, or the like, a method of applying a conductive resin to a drum or a board, and then transferring the resin onto a wiring member, a dispensing method of applying with a dispenser, and the like. is there.
[0043]
As a feature of the present invention, since the conductive resin is applied on the conductive protrusions, in the method of manufacturing the intermediate wiring member A for lamination, the conductive resin flows under the conductive protrusions due to surface tension even when the conductive resin is shifted. In addition, even if the amount of the applied resin varies, the application range is limited to the conductive protrusions, so that the alignment of the application and the control of the application amount are easy. Further, as compared with the case where the conductive resin is applied to the flat surface, the resin can be applied in a smaller range with the same amount of resin, so that it is easy to cope with the formation of a circuit with a narrow pitch. In the method of manufacturing the intermediate wiring member B for lamination, since the conductive resin is supplied to the concave portion, the conductive resin is easily supplied to a predetermined position without dropping. Moreover, since the conductive resin portion is not polished as compared with the intermediate wiring member A for lamination, conductive foreign matter is less likely to adhere to the insulating resin portion.
[0044]
In order to improve the adhesiveness of the conductive resin, it is necessary to increase the ratio of the resin component serving as a binder. However, when the resin component is increased, the resistance value increases. In the present invention, since the conductive resin is applied on the conductive protrusion, the conductive resin can be made thinner than a case where the conductive protrusion having the same height is formed by a single conductive resin. Therefore, the resistance value can be reduced even for a conductive resin having a large resin component.
[0045]
In the method of manufacturing the intermediate wiring members A and B for lamination, examples of the polishing method in the polishing step include roll paper polishing, sand blasting, honing, and lapping, and a machining method using a blade, such as router processing, may be used. . Polishing the insulating resin or the insulating resin and the conductive resin in a semi-cured state has a lower hardness than the cured state, so that the polishing efficiency can be increased. In the method of manufacturing the intermediate wiring member A for lamination, the abrasiveness of the conductive projections is improved as compared with a method of applying an insulating resin without applying the conductive resin to the distal end surface of the conductive projections and drying. Further, when the conductive projection is a hard projection such as a metal, the method of not applying a conductive resin is more difficult to be cut in a polishing step as hard as the polishing step, and thus the surface of the conductive projection after polishing tends to be convex. In the method in which the conductive resin is applied, since the conductive resin is in a semi-cured state, the surface of the conductive protrusion is likely to be flat. It is effective that the hardness in the semi-cured state of the insulating resin and the conductive resin is equal or close to each other in improving the flatness during polishing. On the other hand, in the method of manufacturing the intermediate wiring member B for lamination, since the conductive resin is not applied on the tip surface of the conductive projection at the time of polishing, the surface of the conductive projection tends to be convex after polishing. However, after that, the conductive protrusions are half-etched to form a concave portion, and the conductive resin is applied on the tip surface of the conductive protrusion in the concave portion, so that the convex state is eliminated and a substantially flat surface is formed. Can be.
[0046]
In bonding the wiring member to the insulating resin and the conductive resin, it is effective to roughen the surface of the wiring member in contact with the insulating resin and the conductive resin in order to improve the adhesion. Roughening methods include chemical roughening (etching such as chemical phosphorus-based treatment, chemical phosphoric acid-based treatment, chemical formic acid-based treatment, etc.), mechanical roughening (blasting, etc.), plasma treatment, and metal grain removal. Electrolysis may be applied.
At this time, it is also important to select conditions that can simultaneously roughen not only the surface of the conductive protrusion head but also at least the side surface of the conductive protrusion, and more preferably the surface of the conductive layer that adheres to the insulating resin.
In addition, it is not preferable that a portion that is connected to the conductive resin forms a film that inhibits conductivity depending on roughening. If there is a problem in the electrical characteristics, mask the part that adheres to the conductive resin before roughening, or after roughening, partially remove the film that inhibits the conductivity of the part that adheres to the conductive resin by etching or the like. Good to do.
[0047]
A conductor circuit bonded by heating and pressing is formed on the flattened surface of the intermediate wiring member A for lamination or on the flattened insulating resin surface of the intermediate wiring member B for lamination. The wiring board of the present invention can be manufactured by a method including curing a conductive resin in a cured state and forming a circuit of a conductive layer by partial etching.
Examples of the wiring board manufactured by the method of the present invention include other wiring boards such as a semiconductor package substrate as an interposer used for a semiconductor package, and a motherboard on which a semiconductor package and other electronic components are mounted.
As a method of forming a conductor circuit on the flattened surface or the flattened insulating resin surface of the intermediate wiring member A or B for lamination, for example, a metal foil is bonded by heating and pressing, and then the bonded metal foil is partially etched. For example, there is a method of forming a circuit. Also, using a circuit board having a circuit formed on one side, a double-sided metal foil-clad board having a circuit formed with a metal foil on one side, a multilayer circuit board having an inner layer circuit and having an outer layer circuit on one side, etc. The surface may be brought into contact with the flattened surface of the intermediate wiring member A for lamination or the flattened insulating resin surface of the intermediate wiring member B for lamination, and then laminated by heating and pressing.
[0048]
For example, as described below, a two-layer wiring board can be manufactured using the intermediate wiring member A or B for lamination of the present invention. First, a metal foil is placed on the flattened surface of the intermediate wiring member A for lamination or on the flattened insulating resin surface of the intermediate wiring member B for lamination, and pressure and heat are applied to the metal foil to form an intermediate portion between the metal foil and the intermediate lamination. The wiring member A is adhered, and the semi-cured insulating resin and the semi-cured conductive resin are cured. Next, the conductor layer of the intermediate wiring member A or B for lamination and the bonded metal foil are each formed into a circuit by partial etching, whereby a two-layer wiring board can be manufactured.
[0049]
As the metal foil, for example, a copper foil, an aluminum foil, a nickel foil, a 42 alloy foil, or the like can be used, and the thickness is preferably 12 to 40 μm. The same applies to a metal foil used in a method for manufacturing another wiring board described later.
[0050]
As a method of bonding the intermediate wiring member A or B for lamination and the metal foil, there are a press method of pressing and heating under vacuum and a laminating method of pressing and heating with a roll. The heating and pressurizing are usually performed at a temperature of 150 to 300 ° C and a pressure of 0.49 to 9.8 MPa (5 to 100 kgf / cm ² )). At this time, an adhesion promoter or the like for improving the adhesiveness may be applied to the metal foil in advance. However, the adhesiveness to the conductive resin does not impair the conductivity to the metal foil. This bonding method is the same in the following other method for manufacturing a wiring board.
[0051]
In addition, when the insulating resin and the conductive resin include a thermosetting resin, the curing of the insulating resin and the conductive resin can be performed at the same time when the resin and the metal foil are bonded by heating under pressure. Also, when these resins are thermoplastic materials, they can be bonded by raising the temperature to the softening point, but because they are softened and have high fluidity, flatness cannot be obtained. Temperature and pressure must be controlled to the state. Curing in the case of a photosensitive resin proceeds by heating, but if it is insufficient, after forming an exterior circuit, it is cured by irradiating light and sufficiently exposing it. The same applies to the following methods.
Further, another wiring including the intermediate wiring member A or B for lamination and another intermediate wiring member A or B for lamination (A or B may be used, or both A and B may be used). By using the member, a multilayer wiring board having three or more layers can be manufactured.
[0052]
For example, a multilayer wiring board is manufactured using at least two intermediate wiring members A for lamination or intermediate wiring members B for lamination as follows. A metal foil is placed on the flattening surface of the intermediate wiring member A for lamination, and the metal foil and the intermediate wiring member A for lamination are bonded by applying pressure and heat, and the semi-cured insulating resin and the semi-cured The conductive resin is cured. Next, the conductor layer of the intermediate wiring member A for lamination and / or the adhered metal foil is partially etched to form a circuit, thereby producing a wiring member C. The laminating intermediate wiring member A 'and the wiring member C are laminated such that the flattened surface of the laminating intermediate wiring member A' and the circuit of the wiring member C are in contact with each other, and the wiring member C is applied by applying pressure and heat. And the intermediate wiring member A 'for lamination, and the semi-cured insulating resin and the conductive resin in the semi-cured state of the intermediate wiring member A' for lamination are cured. Thereafter, a circuit is formed by partial etching between the conductor layer of the intermediate wiring member A 'for lamination and the conductor layer or metal foil of the bonded wiring member C on which the circuit is not formed, thereby obtaining a multilayer wiring board. By repeating this, it is possible to further increase the number of layers. When using at least two intermediate wiring members B for lamination, a wiring member D is manufactured in the same manner as described above using the intermediate wiring members B for lamination, and then another intermediate wiring member B 'for lamination with the wiring member D. And a multilayer wiring board is manufactured through the same steps as above.
[0053]
Using the wiring member E in which the semi-cured conductive resin is not applied and the leading end surfaces of the conductive protrusions are exposed on the insulating resin surface, and the intermediate wiring member A or B for lamination, a multilayer as follows. Wiring boards can also be manufactured. First, it has at least three layers of a first metal layer made of a first metal, a second metal layer made of a second metal, and a third metal layer made of a third metal in this order. Is a metal having different etching conditions from each other, and a second metal and a third metal are prepared with a multilayer metal foil having different etching conditions from each other. Forming a plurality of conductive protrusions made of the first metal on the exposed surface of the second metal layer by partially etching the first metal layer of the multilayer metal foil until the second metal layer is exposed; or The first metal layer and the second metal layer are partially etched in this order until the third metal layer is exposed, thereby forming the first metal layer and the second metal layer on the exposed surface of the third metal layer. Forming a plurality of conductive protrusions of two layers (conductive protrusion forming step). Next, on the exposed surface of the second metal layer or the exposed surface of the third metal layer, an insulating resin in a fluid varnish state before curing is applied by printing to a thickness such that the conductive protrusions are embedded in the insulating resin. (Printing process). Thereafter, the printed insulating resin is dried in a semi-cured state or dried or cured in a completely cured state (drying or curing step). Next, by polishing the semi-cured or cured insulating resin, the tip surface of the conductive protrusion is exposed on the insulating resin surface, and the insulating resin surface is flattened (polishing step). Thereafter, the circuit surface is formed by partially etching the unetched second metal layer and the third metal layer or the unetched third metal layer to form a circuit, thereby forming a wiring member E. The member E and the intermediate wiring member A or B for lamination are laminated so that the circuit surface of the wiring member E and the flattened surface of the intermediate wiring member A for lamination or the flattened insulating resin surface of the intermediate wiring member B for lamination are in contact with each other. Then, by applying pressure and heat, the wiring member E and the intermediate wiring member A for lamination are bonded, and the semi-cured insulating resin and the semi-cured conductive resin are cured. Thereafter, the conductor layer of the intermediate wiring member A or B for lamination is partially etched to form a circuit, thereby manufacturing a multilayer wiring board.
[0054]
Alternatively, a circuit formed on the flattening surface of the intermediate wiring member A for lamination or the flattening resin surface of the intermediate wiring member B for lamination by applying a conductive resin by printing may be used. For example, a circuit is formed by screen-printing a conductive resin on the flattened surface of the intermediate wiring member A for lamination, and the circuit is dried to a semi-cured state before fluidity is lost but before a completely cured state is reached. Next, the intermediate wiring member A for lamination on which the circuit of the conductive resin is formed, and another intermediate wiring member A 'for lamination, the surface on which the circuit of the intermediate wiring member A for lamination is formed and the intermediate wiring member A' for lamination are formed. The lamination is performed so that the lamination intermediate wiring member A and the lamination intermediate wiring member A ′ are bonded by applying pressure and heat, and the semi-cured insulating resin and the semi-cured conductive property are applied. Cure the paste. Next, the conductor layer of the intermediate wiring member A for lamination and the conductor layer of the intermediate wiring member A 'for lamination are partially etched to form a circuit, thereby obtaining a multilayer wiring board. In a similar process, a multilayer wiring board can be manufactured using two or more intermediate wiring members B for lamination, or at least two of the intermediate wiring members A for lamination and the intermediate wiring members B for lamination.
[0055]
【Example】
Hereinafter, the present invention will be described more specifically with reference to Examples of the present invention, but the present invention is not limited to these Examples.
Example 1
An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing a state in which a conductive resin is applied to a conductive projection and dried, and then an insulating resin is applied and dried and polished to expose a front end surface of the conductive projection to produce an intermediate wiring member A for lamination. FIG. 5 is a process diagram in which a foil is bonded by heating under pressure and circuits are formed on both sides to produce a two-layer wiring board. Here, the wiring member having the conductive protrusion was manufactured as follows. A three-layer metal foil comprising a copper layer (first metal layer 1) having a thickness of 70 μm, a nickel layer (second metal layer 2 as a barrier layer) having a thickness of 0.2 μm, and a copper layer (conductor layer 3) having a thickness of 10 μm ( Nippon Electrolysis Co., Ltd.) was prepared (FIG. 1 (a)). Using a photo dry film H-K350 (Hitachi Chemical Industry Co., Ltd.), a pattern was formed on the copper layer (first metal layer 1) side having a thickness of 70 μm, and an A process solution (ammonia copper complex salt 20) manufactured by Meltex Co., Ltd. (30% by weight, 10-20% by weight of ammonium chloride and 1-10% by weight of ammonia). 4 was formed (FIG. 1B). The exposed portion of the nickel layer (second metal layer 2) other than under the columnar bumps 4 is selectively removed with an etching solution composed of an aqueous solution of nitric acid and hydrogen peroxide (10% by weight of nitric acid and 5% by weight of hydrogen peroxide). did. As a result, a wiring member in which a plurality of cylindrical conductive protrusions 6 each having a diameter of 250 μm formed of a copper layer and a nickel layer were formed on the surface of the conductor layer 5 formed of a copper layer having a thickness of 10 μm (FIG. 1C) ). The surface of the exposed 10 μm copper layer (conductor layer 5) and the side and top surfaces of the conductive projections were subjected to a chemical phosphoric acid treatment to give a roughening treatment of 2 μm in order to improve the adhesion to the resin.
[0056]
Next, using a conductive resin 7 (Epoxy-based silver paste 118-06SD Creative materials incorporated) and a viscosity of 25 Pa · s, a metal mask having a thickness of 50 μm and a hole having a diameter of 150 μm was prepared corresponding to the conductive protrusion 6. Then, the conductive resin 7 was printed and supplied to the tip end surface of the conductive protrusion 6 by a resin squeegee. Thereafter, by drying at 120 ° C. for 5 minutes, the conductive resin 7 was in a semi-cured state (FIG. 1D). At this time, the thickness of the conductive resin 7 was 30 μm.
As the insulating resin 8, KS6600 (manufactured by Hitachi Chemical Co., Ltd., solid content concentration: 30% by weight) made of a silicone-modified polyamide-imide resin was used. A printing machine (VE-500, manufactured by Toray Engineering Co., Ltd.) embeds and coats all of the conductive projections 6 and the conductive resin 7 with the insulating resin 8 in a fluid varnish state having a viscosity of 40 Pa · s. Printing was performed on the conductor layer 5 through a 150 μm-thick metal mask opened as much as possible. After drying at 120 ° C. for 30 minutes, the insulating resin 8 was in a semi-cured state, and the solvent component was volatilized, as shown in FIG. The thickness of the insulating resin 8 above the conductive protrusions 6 was 30 μm.
[0057]
As shown in FIG. 1 (f), in order to expose the front end surface of the conductive resin 7 of the conductive protrusion 6 with the conductive resin 7 embedded in the insulating resin 8, the semi-cured insulating resin 8 is commercially available. Polishing was carried out with care so as to be polished flat with abrasive paper. Polishing was completed when the conductive resin 7 was polished so as to remain in a thickness of 10 to 20 μm. The diameter of the exposed surface of the conductive resin 7 exposed on the flattened surface 9 was 120 μm.
Thereby, the intermediate wiring member A for lamination could be formed.
Next, as shown in FIG. 1 (g), the intermediate wiring member A for lamination and a copper foil (metal foil 10) were bonded on the flattened surface 9 using a vacuum press. The copper foil (metal foil 10) had a thickness of 35 μm, and the adhesive surface was roughened by a chemical phosphoric acid treatment at 2 μm in order to improve the adhesion to the resin. The bonding conditions were as follows: heating at 180 ° C. for 60 minutes under vacuum, heating at 260 ° C. for 20 minutes, and pressing pressure of 0.8 MPa. A circuit 11 is formed on the laminated copper foil (metal foil 10) and the conductor layer 5 made of copper by partial etching of copper (an aqueous solution having a ferric chloride concentration of 35% by weight and a hydrochloric acid concentration of 3% by weight). A two-layer wiring board as shown in FIG.
[0058]
Example 2
Fig. 2 shows the conductive protrusions coated with an insulating resin, dried and polished to expose the heads of the conductive protrusions. The conductive protrusions are then half-etched, and the conductive resin is embedded in the etched portions and dried. FIG. 4 is a process diagram in which a two-layer wiring board is manufactured by forming a wiring board B by laminating and then bonding a metal foil by heating under pressure and forming a circuit on both sides. The steps of FIGS. 2A, 2B and 2C are performed in the same manner as the steps of FIGS. 1A, 1B and 1C of the first embodiment, and A wiring member having an elastic protrusion was manufactured. Next, KS6600 (manufactured by Hitachi Chemical Co., Ltd.) made of a silicone-modified polyamide-imide resin was used as the insulating resin 8, and the insulating resin 8 in a fluid varnish state having a viscosity of 40 Pa · s was printed on a printing machine (VE). -500, manufactured by Toray Engineering Co., Ltd.), and printed on the conductor layer 5 through a 120 μm-thick metal mask that was opened so that all of the plurality of conductive protrusions 6 could be embedded and applied. By drying at 120 ° C. for 30 minutes, the insulating resin 8 was in a semi-cured state, and the solvent component was volatilized to form a cross-sectional shape in which the upper portion of the conductive protrusion 6 was raised as shown in FIG. The thickness of the insulating resin 8 above the conductive protrusions 6 was 30 μm.
[0059]
As shown in FIG. 2 (e), in order to expose the tip surface of the conductive protrusion 6 embedded in the insulating resin 8, care is taken to flatly polishes the semi-cured insulating resin 8 with a commercially available abrasive paper. Polished while polishing. Polishing was completed when the polishing was performed until the tip end surface of the conductive protrusion 8 was completely exposed. The diameter of the exposed portion of the conductive protrusion 6 exposed on the flattening insulating resin surface 12 was 250 μm. Next, the conductive layer 5 is protected with a protective tape so as not to be etched, and the conductive protrusions 6 made of copper are averaged with an acid-based etching solution (an aqueous solution having a ferric chloride concentration of 35% by weight and a hydrochloric acid concentration of 3% by weight). By half etching of about 20 μm, a recess 13 was formed on the flattening insulating resin surface 12 with the tip end surface 2 of the conductive projection 6 as a bottom, as shown in FIG.
Next, using a conductive resin 7 (epoxy-based silver paste 118-06SD Creative Materials Incorporated) and a viscosity of 25 Pa · s, a metal mask having a thickness of 30 μm and a hole having a diameter of 200 μm was prepared corresponding to the conductive protrusion 6. Then, a conductive resin 7 was printed and supplied on the tip end surface of the conductive protrusion 6 half-etched with a resin squeegee. Thereafter, the conductive resin 7 was semi-cured by drying at 120 ° C. for 5 minutes (FIG. 2G). At this time, the thickness of the conductive resin 7 was 20 μm. Thereby, the intermediate wiring member B for lamination could be formed.
[0060]
Next, as shown in FIG. 2H, the intermediate wiring member B for lamination and a copper foil (metal foil 10) were bonded on the flattening insulating resin surface 12 by using a vacuum press. The copper foil (metal foil 10) had a thickness of 35 μm, and the adhesive surface was roughened by a chemical phosphoric acid treatment at 2 μm in order to improve the adhesion to the resin. The bonding conditions were as follows: heating at 180 ° C. for 60 minutes under vacuum, heating at 260 ° C. for 20 minutes, and pressing pressure of 0.8 MPa. A circuit 11 was formed on the laminated copper foil (metal foil 10) and the conductor layer 5 by partial etching of copper to produce a two-layer wiring board as shown in FIG. 2 (i).
[0061]
Example 3
FIG. 3 shows an example in which insulating resins having different compositions are applied many times during the application of the insulating resin shown in FIG. As the first insulating resin for forming the relatively hard core layer 8a, KS6600 (manufactured by Hitachi Chemical Co., Ltd.) made of a silicone-modified polyamideimide resin contains 40 wt% of silica filler having an average particle diameter of 1.5 μm (solvent). (After volatilization). The above resin having a viscosity of 80 Pa · s in a fluid varnish state was opened by a printing machine (VE-500, manufactured by Toray Engineering Co., Ltd.) so that all of the plurality of conductive projections 6 could be applied so as to be embedded. Printing was performed through a metal mask having a thickness of 50 μm. By drying at 120 ° C. for 10 minutes, the surface is in a semi-cured state. The thickness of the core layer 8a was about 50 μm. Next, using a filler-less KS6600 (manufactured by Hitachi Chemical Co., Ltd.) as the second insulating resin for forming the relatively soft surface layer 8b, the above resin having a viscosity of 40 Pa · s in a fluid varnish state was used as a printing machine. (VE-500, manufactured by Toray Engineering Co., Ltd.) Further printing was carried out through a 100 μm-thick metal mask which was opened so that the entirety of the plurality of conductive protrusions 6 and conductive resin 7 could be applied so as to be embedded. By drying at 120 ° C. for 20 minutes, the entire first insulating resin and the second insulating resin were in a semi-cured state. The thickness of the surface layer 8b was about 20 μm. As a result, as shown in FIG. 3A, the core layer 8a made of a hard first insulating resin and the surface layer 8b made of a soft second insulating resin with good adhesion are formed, as shown in FIG. In a two-layer structure.
As shown in FIG. 3 (b), in order to expose the end of the conductive resin 7 of the conductive protrusion 6 with the conductive resin 7 embedded in the insulating resin 8, the insulating resin has a semi-cured two-layer structure. The surface layer 8b of No. 8 was polished with care so as to be polished flat with a commercially available polishing paper. Polishing was completed when the conductive resin 7 was polished so as to remain in a thickness of 10 to 20 μm. The diameter of the exposed portion of the conductive resin 7 was 120 μm.
[0062]
Example 4
FIG. 4 shows a lamination intermediate wiring member A ′ manufactured in the same manner as the lamination intermediate wiring member A of FIG. 1F in Example 1, and a two-layer wiring board of FIG. FIG. 4 is a process diagram for fabricating a three-layer wiring board by laminating the above. The intermediate wiring member A 'for lamination was implemented except that the diameter of the conductive protrusion 6' was changed to 100 µm, the diameter of the exposed portion of the conductive resin 7 'was changed to 50 µm, and the arrangement of the conductive protrusion 6' was changed. It was produced in the same manner as the lamination intermediate wiring member A of Example 1. 4A, a two-layer wiring board was prepared and used as a wiring member C in the same manner as in Example 1. At this time, the circuit 11 on the flattened surface 9 of the wiring member C was formed by previously half-etching the conductor layer to reduce the thickness to 5 to 10 μm in order to improve the embedding property. . As shown in FIG. 4 (b), the polished flat surface 9 'of the intermediate wiring member A' for lamination and the surface of the wiring member C having the thinned circuit 11 are brought together, and the pressure is reduced to 0. After heating at 180 ° C. for 60 minutes at 8 MPa, the mixture was cured by heating at 260 ° C. for 20 minutes. Thereafter, as shown in FIG. 4C, an outer layer circuit was formed on the conductor layer 5 'of the intermediate wiring member A' for lamination by partial etching under the same conditions as in Example 1 to produce a three-layer wiring board.
[0063]
Example 5
FIG. 5 shows the lamination intermediate wiring member A using the lamination intermediate wiring member A ′ of FIG. 4A produced in Example 4 and the structure of FIG. 2E produced during the process of Example 2. FIG. 11 is a process diagram for manufacturing a pseudo three-layer wiring board by laminating a used wiring member E; First, in the same manner as in Example 4, an intermediate wiring member for lamination A ′ is prepared and prepared as an intermediate wiring member for lamination A. Further, as shown in FIG. 5B, a circuit 11 is formed on the conductor layer 5 with an acid-based etchant from the state of FIG. 5D of the second embodiment, and a wiring member E having a circuit surface 14 is prepared. . As shown in FIG. 5C, the flattened surface 9 of the intermediate wiring member A for lamination and the circuit surface 14 of the wiring member E are combined, and heated at 180 ° C. for 60 minutes at a pressure of 0.8 MPa by a vacuum press. It was cured by heating at 260 ° C. for 20 minutes. Thereafter, as shown in FIG. 4D, the conductor layer 5 was formed into a circuit 11 by using an acid-based etching solution to produce a pseudo three-layer wiring board.
[0064]
Example 6
FIG. 6 shows a multilayer wiring plan produced by laminating a circuit pattern printed with a conductive paste on the polished flat surface of the intermediate wiring member A for lamination and another intermediate wiring member A 'for lamination. FIG. First, as shown in FIG. 6A, the same intermediate wiring member A 'for lamination as shown in FIG. The conductive resin 15 (epoxy silver paste 118-06SD Creative materials) is provided on the polished flat surface 9 of the lamination intermediate wiring member A manufactured by the same process except that the arrangement of the conductive protrusions 6 is changed. A 30 μm-thick screen mask for printing a circuit pattern was prepared using an incorporation and a viscosity of 25 Pa · s, and printing was performed using a resin squeegee. Thereafter, by drying at 120 ° C. for 5 minutes, the conductive resin 15 was in a semi-cured state, and the member shown in FIG. 6B was obtained. At this time, the thickness of the conductive resin 15 printed with the circuit was 10 μm.
As shown in FIG. 6C, the flattening surface 9 'of the intermediate wiring member A' for lamination of FIG. 6A and the conductive resin 15 of the intermediate wiring member A for lamination of FIG. 6B are formed. After being combined with the circuit surface and heated at 180 ° C. for 60 minutes by a vacuum press at a pressure of 0.8 MPa, the mixture was cured by heating at 260 ° C. for 20 minutes. Thereafter, as shown in FIG. 4 (d), the conductor layer 5 and the conductor layer 5 'were partially etched with an acid-based etchant to form an outer circuit 11, thereby producing a three-layer wiring board.
[0065]
Example 7
FIG. 7 is a process example of manufacturing a wiring board corresponding to higher density by limiting the area of application of the conductive resin of the first embodiment. It is the same as the first embodiment, except for the portion where the conductive resin is applied.
First, a wiring member having a plurality of conductive protrusions on the surface was manufactured in the same manner as in the steps of FIGS. 1A, 1B, and 1C of Example 1. Next, as shown in FIG. 7A, a conductive resin 7 was applied on the end surface of the conductive protrusion 6 of the wiring member. The conductive resin application step of FIG. 7A uses a conductive resin 7 (epoxy-based silver paste 118-06SD Creative materials incorporated) and a viscosity of 25 Pa · s to form a hole having a diameter of 70 μm corresponding to the conductive protrusion 6. Was prepared, and a conductive resin 7 was printed and supplied to the tip surface of the conductive protrusion 6 with a resin squeegee. Thereafter, the conductive resin 7 was dried in a semi-cured state by drying at 120 ° C. for 5 minutes. At this time, the thickness (height) of the conductive resin 7 was 30 μm.
[0066]
Next, as shown in FIG. 7B, in the same manner as in Example 1, the insulating resin 8 was applied and dried to obtain a semi-cured state. Thereafter, as shown in FIG. 7C, the insulating resin 8 was polished in the same manner as in Example 1 to form a flattened surface 9 in which the tip end surface of the conductive resin 7 was exposed. The diameter of the exposed front end surface of the conductive resin 7 was φ50 μm. Next, as shown in FIG. 7D, a copper foil is laminated as a metal foil 10 on the flattened surface 9 and bonded by heating and pressing as in the first embodiment, and the insulating resin 8 and the conductive resin 7 was cured. Next, as shown in FIG. 7E, the circuit 11 is formed by partially etching the metal foil 10 and the conductor layer 5 using the same acid-based etchant as in Example 1, thereby producing a two-layer wiring board. did. In addition, only the metal foil 10 of the member shown in FIG. 7D was formed in a circuit, and the conductor layer 5 was completely removed by etching to produce a pseudo two-layer wiring board.
[0067]
【The invention's effect】
As described above, the intermediate wiring member for lamination of the present invention can form a laminated surface excellent in adhesion, flatness and reliability of interlayer connection when laminated with various wiring members. Further, a wiring board manufactured using the intermediate wiring member for lamination has excellent adhesion between layers, connection reliability, and excellent flatness.
[Brief description of the drawings]
FIG. 1 is a process diagram showing one embodiment of a manufacturing process of a lamination intermediate wiring member A and a wiring board manufacturing process using the same according to the present invention.
FIG. 2 is a process chart showing one embodiment of a manufacturing process of the intermediate wiring member B for lamination according to the present invention and a manufacturing process of a wiring board using the same.
FIG. 3 is a process diagram showing a manufacturing process of another embodiment of the intermediate wiring member for lamination A according to the present invention.
FIG. 4 is a process diagram showing one embodiment of manufacturing a multilayer wiring board using the intermediate wiring member A for lamination according to the present invention.
FIG. 5 is a process diagram showing another embodiment of manufacturing a multilayer wiring board using the intermediate wiring member for lamination A according to the present invention.
FIG. 6 is a process chart showing another embodiment of manufacturing a multilayer wiring board using the intermediate wiring member A for lamination according to the present invention.
FIG. 7 is a process chart showing another embodiment of the manufacturing process of the intermediate wiring member A for lamination according to the present invention and one embodiment of the manufacturing process of the wiring board using the same.
[Explanation of symbols]
1 First metal layer
2 Second metal layer
3 Third metal layer
4 Pillar bump
5, 5 'conductor layer
6, 6 'conductive protrusion
7, 7 'conductive resin
8, 8 'insulating resin
9, 9 'flattened surface
10 Metal foil
11 circuits
12 Flattened insulating resin surface
13 recess
14 Circuit side
15 Conductive resin

Claims

(1) a wiring member having a conductive layer and a plurality of conductive protrusions protruding on one surface of the conductive layer; (2) a conductive resin applied on a tip end surface of the conductive protrusion of the wiring member; A) an intermediate wiring member for lamination having an insulating resin in which a front end surface of a conductive resin is exposed on a surface side of the wiring member having the conductive protrusion and the conductive protrusion and the conductive resin are embedded; And the insulating resin has no fluidity but is in a semi-cured state before reaching a completely cured state, and the insulating resin surface and the exposed surface of the conductive resin exposed on the insulating resin surface form a flat planarized surface. Intermediate wiring member A for lamination.

The wiring member, wherein the conductor layer comprises at least a third metal layer, and the conductive protrusions comprise two layers of a second metal layer on the conductor layer and a first metal layer on the second metal layer. Or, the wiring member is such that the conductor layer is composed of at least a third metal layer and a second metal layer on the third metal layer, and the conductive protrusion is formed on the second metal layer of the conductor layer. The intermediate wiring member for lamination A according to claim 1, wherein the intermediate wiring member A is made of a first metal.

The intermediate wiring member for lamination according to claim 2, wherein the first metal and the second metal are metals having different etching conditions from each other, and the second metal and the third metal are metals having different etching conditions from each other.

The insulating resin comprises at least two layers of a core layer made of the first insulating resin in contact with the conductor layer and a surface layer made of the second insulating resin on the conductor layer, and the first insulating resin in a semi-cured state is The intermediate wiring member A for lamination according to any one of claims 1 to 3, which is harder than the second insulating resin in a semi-cured state.

The intermediate wiring member A for lamination according to any one of claims 1 to 4, wherein the area of the exposed surface of the conductive resin exposed on the insulating resin surface is smaller than the area of the tip end surface of the conductive protrusion.

(1) a wiring member having a conductive layer and a plurality of conductive protrusions protruding on one surface of the conductive layer; and (2) an insulating resin in which the conductive protrusions are embedded on the side of the wiring member having the conductive protrusions. An insulating resin forming a flattened insulating resin surface except that the surface has a concave portion whose bottom is the front end surface of the conductive projection; and (3) a top surface of the conductive projection. An intermediate wiring member for lamination having an applied conductive resin, wherein the conductive resin and the insulating resin have no fluidity but are in a semi-cured state before reaching a completely cured state.

The wiring member, wherein the conductor layer is made of a third metal, and the conductive protrusion is made of two layers of a second metal layer on the conductor layer and a first metal layer on the second metal layer, or The wiring member has a conductor layer made of a third metal layer and a second metal layer on the third metal layer, and the conductive protrusions are made of a first metal on the second metal layer of the conductor layer. 7. The intermediate wiring member B for lamination according to claim 6, wherein:

8. The intermediate wiring member B for lamination according to claim 7, wherein the first metal and the second metal are metals having different etching conditions, and the second metal and the third metal are metals having different etching conditions.

The insulating resin comprises at least two layers of a core layer made of the first insulating resin in contact with the conductor layer and a surface layer made of the second insulating resin on the conductor layer, and the first insulating resin in a semi-cured state is 9. The intermediate wiring member B for lamination according to claim 6, which is harder than the second insulating resin in a semi-cured state.

Heating on the flattened surface of the intermediate wiring member for lamination A according to any one of claims 1 to 5 or on the flat insulating resin surface of the intermediate wiring member B for lamination according to any one of claims 6 to 9 A wiring board obtained by forming a conductor circuit bonded by applying pressure, curing a semi-cured insulating resin and a semi-cured conductive resin, and forming a circuit by partial etching of a conductor layer.

The wiring board according to claim 10, which is used as a substrate for a semiconductor package.

A conductive resin coating step of applying a conductive resin to a tip surface of the conductive protrusion of the wiring member having a plurality of conductive protrusions protruding on one surface of the conductive layer and the conductive layer, the flowability of the applied conductive resin is A conductive resin drying step of drying to a semi-cured state before disappearing but reaching a completely cured state, an insulating resin in a fluid varnish state before curing is printed on a surface of the wiring member having conductive protrusions. Insulation resin printing process in which conductive protrusions and semi-cured conductive resin are applied to a thickness embedded in the insulating resin, the printed insulating resin loses fluidity but is in a semi-cured state before reaching a completely cured state An insulating resin drying step of drying until the semi-cured insulating resin is polished to expose the semi-cured conductive resin, and to flatten the surface of the insulating resin including the exposed surface of the conductive resin. Contract with process Method for manufacturing a laminated intermediate wiring member A according to claim 1.

A first metal layer made of a first metal, a second metal layer made of a second metal, and a third metal layer made of a third metal are used as the wiring member in a multilayer metal foil having at least three layers in this order. Fabricated by forming a conductive layer composed of the second metal layer and the third metal layer and a plurality of conductive projections composed of the first metal by partially removing the metal layer until the second metal layer is exposed. Or by removing the first metal layer and the second metal layer partially until the third metal layer is exposed by using the multilayer metal foil, so that the conductor layer made of the third metal layer and the second metal layer are removed. 13. The method of manufacturing the intermediate wiring member A for lamination according to claim 12, wherein the plurality of conductive protrusions are formed by forming a plurality of conductive protrusions each including a metal layer and a third metal layer on the second metal layer.

The first metal and the second metal are metals having different etching conditions from each other, the second metal and the third metal are metals having different etching conditions from each other, and the first metal layer is partially removed by etching. 14. The method of manufacturing the intermediate wiring member A for lamination according to claim 13, wherein the first metal layer and the second metal layer are partially removed by sequentially etching under different etching conditions.

In the insulating resin printing step, at least two types of insulating resins, a first insulating resin and a second insulating resin, are used as the insulating resin, the first insulating resin is printed on the conductor layer to form a core layer, and then the second resin is formed. The lamination according to any one of claims 12 to 14, wherein the surface layer is formed by printing an insulating resin, and the first insulating resin in the semi-cured state is harder than the second insulating resin in the semi-cured state. Of manufacturing the intermediate wiring member A for use.

The conductive resin layer and the wiring member having a plurality of conductive protrusions protruding on one side of the conductive layer, the insulating resin in a fluid varnish state before curing is printed on the surface having the conductive protrusions by printing. Insulating resin printing process to apply the thickness to the extent that the protrusions are embedded in the insulating resin, Insulating resin drying process to dry the printed insulating resin to a semi-cured state before the fluidity is lost but before it reaches a completely cured state, a semi-cured state Polishing the insulating resin to expose the tip surface of the conductive protrusions, and flatten the semi-cured insulating resin surface to form a planarized insulating resin surface, exposing the exposed conductive protrusions A half-etching step of performing half-etching by etching from the etched tip end face, a conductive resin applying step of applying a conductive resin to the tip end face of the half-etched conductive projection, and Sexual resin becomes no fluidity before reaching the full cure conditions, method for manufacturing a laminated intermediate wiring member B of claim 6 having a conductive resin drying step of drying to a semi-cured state.

A first metal layer made of a first metal, a second metal layer made of a second metal, and a third metal layer made of a third metal are used as the wiring member in a multilayer metal foil having at least three layers in this order. Fabricated by forming a conductive layer composed of the second metal layer and the third metal layer and a plurality of conductive projections composed of the first metal by partially removing the metal layer until the second metal layer is exposed. Or by removing the first metal layer and the second metal layer partially until the third metal layer is exposed by using the multilayer metal foil, so that the conductor layer made of the third metal layer and the second metal layer are removed. 17. The method of manufacturing the intermediate wiring member B for lamination according to claim 16, wherein the plurality of conductive protrusions are formed by forming a plurality of conductive protrusions including a metal layer and a first metal layer on the second metal layer.

The first metal and the second metal are metals having different etching conditions from each other, the second metal and the third metal are metals having different etching conditions from each other, and the first metal layer is partially removed by etching. 18. The method for manufacturing the intermediate wiring member B for lamination according to claim 17, wherein the first metal layer and the second metal layer are partially removed by sequentially etching under different etching conditions.

In the insulating resin printing step, at least two types of insulating resins, a first insulating resin and a second insulating resin, are used as the insulating resin, the first insulating resin is printed on the conductor layer to form a core layer, and then the second resin is formed. The lamination according to any one of claims 16 to 18, wherein the surface layer is formed by printing an insulating resin, and the first insulating resin in the semi-cured state is harder than the second insulating resin in the semi-cured state. Manufacturing method of the intermediate wiring member B for use.

On the flattening surface of the intermediate wiring member A for lamination according to any one of claims 1 to 5 or on the flattening insulating resin surface of the intermediate wiring member B for lamination according to any one of claims 6 to 9, A method for manufacturing a wiring board, comprising forming a conductor circuit bonded by heating and pressing, curing a semi-cured insulating resin and a semi-cured conductive resin, and forming a circuit by partial etching of a conductor layer.

The method for manufacturing a wiring board according to claim 20, wherein the wiring board is a substrate for a semiconductor package.

A metal foil is placed on the flattening surface of the intermediate wiring member for lamination A according to any one of claims 1 to 5, and the metal foil and the intermediate wiring member A for lamination are bonded by applying pressure and heat. And a step of curing the semi-cured insulating resin and the semi-cured conductive resin, and a step of forming a circuit by partially etching the metal foil bonded to the conductor layer of the intermediate wiring member for lamination A, respectively. Plate manufacturing method.

The method for manufacturing a wiring board according to claim 22, wherein the wiring board is a substrate for a semiconductor package.

A metal foil is placed on the flattening insulating resin surface of the intermediate wiring member for lamination B according to any one of claims 6 to 9, and the metal foil and the intermediate wiring member B for lamination are formed by applying pressure and heat. Bonding a semi-cured insulating resin and a semi-cured conductive resin, and forming a circuit by partially etching the metal foil bonded to the conductor layer of the intermediate wiring member B for lamination, respectively. A method for manufacturing a wiring board.

The method for manufacturing a wiring board according to claim 24, wherein the wiring board is a substrate for a semiconductor package.

A metal foil is placed on the flattened surface of the intermediate wiring member for lamination A according to any one of claims 1 to 5, and the metal foil and the intermediate wiring member for lamination A are bonded by applying pressure and heat, and A step of curing the semi-cured insulating resin and the semi-cured conductive resin, and forming a circuit by partially etching the conductor layer of the intermediate wiring member for lamination A and / or the bonded metal foil to produce a wiring member C A step of contacting the intermediate wiring member for lamination A ′ and the wiring member C according to any one of claims 1 to 5 with the flattening surface of the intermediate wiring member for lamination A ′ and the circuit of the wiring member C. By applying pressure and heat, the wiring member C is bonded to the intermediate wiring member A 'for lamination, and the semi-cured insulating resin and the conductive material in the semi-cured state of the intermediate wiring member A' for lamination are laminated. Step of curing the resin, bonding with the conductor layer of the intermediate wiring member A 'for lamination Method for manufacturing a multilayer wiring board having the a conductive layer or metal foil is not the circuit formation of the wiring member C, and step of the circuit formed by partial etching.

The manufacturing method according to claim 26, wherein the multilayer wiring board is a multilayer board for a semiconductor package.

A metal foil is placed on the flattening insulating resin surface of the intermediate wiring member for lamination B according to any one of claims 6 to 9, and the metal foil and the intermediate wiring member B for lamination are bonded by applying pressure and heat. And curing the semi-cured insulating resin and the semi-cured conductive resin, and partially forming a circuit by partially etching the conductive layer of the intermediate wiring member for lamination B and / or the bonded metal foil. The step of manufacturing, the intermediate wiring member for lamination B 'and the wiring member D according to any one of claims 6 to 9, the flattening insulating resin surface of the intermediate wiring member for lamination B' and the wiring member D The wiring member D and the intermediate wiring member for lamination B ′ are adhered by applying pressure and heat so that the circuit is in contact with the circuit, and the semi-cured insulating resin and semi-cured state of the intermediate wiring member for lamination B ′ are applied. Curing the conductive resin in the state, the lamination of the intermediate wiring member B ' Collector layer and, the adhered conductive layer or metal foil is not the circuit formation of the wiring member D, manufacturing method for a multilayer wiring board comprising a step of forming a circuit by partial etching.

The method according to claim 28, wherein the multilayer wiring board is a multilayer board for a semiconductor package.

It has at least three layers of a first metal layer made of a first metal, a second metal layer made of a second metal, and a third metal layer made of a third metal in this order, and the first metal and the second metal are mutually separated. A multi-layered metal foil having different etching conditions and a second metal and a third metal having different etching conditions is prepared, and the first metal layer is partially etched until the second metal layer is exposed. Thereby, a plurality of conductive protrusions made of the first metal are formed on the exposed surface of the second metal layer, or the first metal layer and the second metal layer are sequentially formed in this order until the third metal layer is exposed. Forming a plurality of conductive protrusions of a first metal layer and a second metal layer on the exposed surface of the third metal layer by partially etching the second metal layer; On the exposed surface of the layer or on the exposed surface of the third metal layer, before curing. Printing process of applying insulating resin in the shape of varnish to the thickness by which the conductive protrusions are embedded in the insulating resin by printing; drying the printed insulating resin in a semi-cured state or drying or curing it in a completely cured state Drying or curing step, polishing the semi-cured or cured insulating resin, exposing the tip surface of the conductive projection on the insulating resin surface, and polishing the insulating resin surface, flattening the insulating resin surface, A step of forming a circuit surface by partially etching a second metal layer and a third metal layer or an unetched third metal layer to form a circuit, thereby manufacturing a wiring member E; 5. Laminating the intermediate wiring member A for lamination according to any one of 5 above so that the circuit surface of the wiring member E and the flattened surface of the intermediate wiring member A for lamination are in contact with each other, and applying pressure and heat. Bonding the wiring member E and the intermediate wiring member A for lamination and curing the semi-cured insulating resin and the conductive resin in the semi-cured state, and partially etching the conductor layer of the intermediate wiring member A for lamination. A method for manufacturing a multilayer wiring board having a step of forming a circuit by heating.

The method according to claim 30, wherein the multilayer wiring board is a multilayer board for a semiconductor package.

It has at least three layers of a first metal layer made of a first metal, a second metal layer made of a second metal, and a third metal layer made of a third metal in this order, and the first metal and the second metal are mutually separated. A multi-layered metal foil having different etching conditions and a second metal and a third metal having different etching conditions is prepared, and the first metal layer is partially etched until the second metal layer is exposed. Thereby, a plurality of conductive protrusions made of the first metal are formed on the exposed surface of the second metal layer, or the first metal layer and the second metal layer are sequentially formed in this order until the third metal layer is exposed. Forming a plurality of conductive protrusions of a first metal layer and a second metal layer on the exposed surface of the third metal layer by partially etching the second metal layer; On the exposed surface of the layer or on the exposed surface of the third metal layer, before curing. Printing process of applying insulating resin in the shape of a varnish to the thickness where the conductive protrusions are embedded in the insulating resin by printing; drying the printed insulating resin in a semi-cured state or drying or curing it in a completely cured state Drying or curing step, polishing the semi-cured or cured insulating resin, exposing the tip surface of the conductive projection on the insulating resin surface, and polishing the insulating resin surface, flattening the insulating resin surface, 7. A step of forming a circuit surface by partially etching a second metal layer and a third metal layer or an unetched third metal layer to form a circuit, thereby manufacturing a wiring member E; 9 is laminated so that the circuit surface of the wiring member E and the flattening insulating resin surface of the laminating intermediate wiring member B are in contact with each other, and pressure and heat are applied thereto. Bonding the wiring member E and the intermediate wiring member B for lamination and curing the semi-cured insulating resin and the conductive resin in the semi-cured state, and removing the conductive layer of the intermediate wiring member B for lamination. A method for manufacturing a multilayer wiring board having a step of forming a circuit by partial etching.

33. The manufacturing method according to claim 32, wherein the multilayer wiring board is a multilayer board for a semiconductor package.

A circuit is formed by screen-printing a conductive resin on the flattened surface of the laminating intermediate wiring member A according to any one of claims 1 to 5, and the fluidity is lost but before a completely cured state is reached. The step of drying to a semi-cured state, the lamination intermediate wiring member A and the lamination intermediate wiring member A ′ according to any one of claims 1 to 5, and the circuit-formed surface of the lamination intermediate wiring member A. The lamination is performed so that the flattening surface of the lamination intermediate wiring member A 'is in contact with the lamination intermediate wiring member A and the lamination intermediate wiring member A' is adhered by applying pressure and heat, and the semi-cured insulation is provided. A multilayer comprising a step of curing a resin and a conductive paste in a semi-cured state, and a step of forming a circuit by partially etching the conductor layer of the intermediate wiring member A for lamination and the conductor layer of the intermediate wiring member A 'for lamination. Manufacturing method of wiring board.

The manufacturing method according to claim 34, wherein the multilayer wiring board is a multilayer board for a semiconductor package.

A circuit is formed by screen-printing a conductive resin on the flattening insulating resin surface of the intermediate wiring member for lamination B according to any one of claims 6 to 9, and the fluidity is lost but before a completely cured state is reached. In the step of drying to a semi-cured state, the intermediate wiring member B for lamination and the intermediate wiring member B 'for lamination according to any one of claims 6 to 9 were formed into a circuit of the intermediate wiring member B for lamination. The intermediate wiring member B for lamination and the intermediate wiring member B 'for lamination are adhered to each other by applying pressure and heat so that the surface and the flattening insulating resin surface of the intermediate wiring member B' for lamination are in contact with each other. A step of curing the cured insulating resin and the semi-cured conductive paste; and forming a circuit by partially etching the conductor layer of the intermediate wiring member B for lamination and the conductor layer of the intermediate wiring member B 'for lamination. A method for manufacturing a multilayer wiring board having a process.

The method according to claim 36, wherein the multilayer wiring board is a multilayer board for a semiconductor package.