JP3674937B2 - Radiation sensitive resin composition - Google Patents

Description

【００２６】
〔式（Ａ）、（Ｂ）および（Ｃ）の各々において、
Ｒ¹はメチル基、エチル基、プロピル基などのアルキル基であり、
Ｒ²は、メチレン基、エチレン基、プロピレン基などのアルキレン基であり、
Ｒ³は、メチル基、エチル基、プロピル基、ヘキシル基等のアルキル基；フェニル基、キシリル基等のアリール基；式：
【００２７】
【化２】

【００２８】
（ここで、ｘは０〜５０の整数である）
で表わされるジメチルシロキサン残基、Ｒ²に関して例示したと同様のアルキレン基、フェニレン基、または下記の式（１）〜（５）で表わされる基を示し、
【００２９】
【化３】

（ここでｙは１〜５０の整数である）、
【００３０】
【化４】

（ここで、ｘは単結合または−ＣＨ₂−、−Ｃ（ＣＨ₃）₂−、−Ｃ（ＣＦ₃）₂−、もしくは−ＳＯ₂−で示される２価の基である）、
【００３１】
【化５】

ｎは、Ｒ³の価数に等しく、１〜４の整数である。〕
【００３２】
これらの式（Ａ）〜式（Ｃ）で表わされる化合物の具体例としては、ビス〔（３−エチル−３−オキセタニルメトキシ）メチル〕ベンゼン（東亜合成社製商品名「ＸＤＯ」）、ビス〔（３−エチル−３−オキセタニルメトキシ）メチル−フェニル〕メタン、ビス〔（３−エチル−３−オキセタニルメトキシ）メチル−フェニル〕エーテル、ビス〔（３−エチル−３−オキセタニルメトキシ）メチル−フェニル〕プロパン、ビス〔（３−エチル−３−オキセタニルメトキシ）メチル−フェニル〕スルホン、ビス〔（３−エチル−３−オキセタニルメトキシ）メチル−フェニル〕ケトン、ビス〔（３−エチル−３−オキセタニルメトキシ）メチル−フェニル〕ヘキサフロロプロパン、トリ〔（３−エチル−３−オキセタニルメトキシ）メチル〕ベンゼン、テトラ〔（３−エチル−３−オキセタニルメトキシ）メチル〕ベンゼン、並びに下記の化学式（Ｄ）〜（Ｈ）で示される化合物を挙げることができる。
【００３３】
【化６】

【００３４】
以上の他、高分子量の多価オキセタン環を有する化合物も用いることができ、その具体例としては、例えばオキセタンオリゴマー（商品名「Ｏｌｉｇｏ−ＯＸＴ」東亞合成社製）並びに下記の化学式（Ｉ）〜（Ｋ）で示される化合物などを挙げることができる。
【００３５】
【化７】

（これらの式中、ｐ、ｑおよびｓは、１〜１０，０００の整数である。）
【００３６】
チイラン化合物
チイラン化合物は、分子中にチイラニル基を２個以上有する化合物で、チイラニル基以外の官能基を有していてもよく、またその分子量は、特に限定されないが、通常、７０〜２０，０００である。チイラン化合物は、一般にオキシラン化合物中のオキシラン環の酸素原子を硫黄原子に置換することにより合成される。例えば、 J.M.Charlesworth J. Polym. Sc. Polym.Phys. 17 329 (1979)に示される方法等によりチオシアン酸塩を用いるか、或いは R. D. Schuetz et al., J. Org. Chem. 26 3467 (1961) に示される方法等によりチオ尿素を用いて合成することができる。また、環状カーボネトからの合成方法も、S.Seales et al. J. Org. Chem., 27 2832 (1962) 等に示されている。合成可能なチイラン化合物は、M. Sander, Chem. Rev. 66 297 (1966)中の Table-Iに示されているが、本発明の具体例として、例えば、グリシジルアクリレート、グリシジルメタクリレート、３，４−エポキシシクロヘキシルアクリレート、３，４−エポキシシクロヘキシルメタクリレート並びにこれらエポキシ化合物の重合体またはこれらエポキシ化合物と他の重合性単量体（例えばスチレン、ブタジエン、メチルメタクリレート、ブチルアクリレート、ヒドロキシエチルメタクリレート等）との共重合体；ビスフェノール型エポキシ樹脂、ノボラック型エポキシ樹脂、クレゾールノボラック型エポキシ樹脂等に代表されるグリシジルエーテル型エポキシ樹脂類；グリシジルエステル型エポキシ樹脂類；芳香族グリシジルアミン型エポキシ樹脂類；脂環式エポキシ樹脂類；複素環式エポキシ樹脂類；液状ゴム変性エポキシ樹脂類等のオキシラン環含有化合物のオキシラン環中の酸素原子を硫黄原子に置換したチイラン化合物を挙げることができる。
【００３７】
これらＣ成分は、Ａ〜Ｃ成分の合計量に対して８〜６０重量％であり、好ましくは、１０〜５０重量％である。Ｃ成分の配合割合が少なすぎると、硬化後の樹脂の強度、耐熱性が低下するおそれがあり、また多すぎると、アルカリ現像性が低下するおそれがある。
【００３８】
〔Ｄ成分〕
Ｄ成分は下記一般式（Ｌ）〜（Ｎ）で表されるハロメチル−１，３，５−トリアジン化合物であり、光重合開始剤として作用する。
一般式（Ｌ）：
【００３９】
【化８】

一般式（Ｍ）：
【００４０】
【化９】

一般式（Ｎ）：
【００４１】
【化１０】

【００４２】
一般式（Ｌ）〜（Ｍ）で定義されるアルキル基の例としては、メチル基、エチル基、プロピル基、ブチル基、ペンチル基、ヘキシル基、ヘプチル基、オクチル基、ノニル基などが挙げられる。アルコキシ基、アルコキシカルボニル基またはフッ化アルキル基のアルキル基の例も上記と同様である。また、ハロゲン原子としては、Ｃｌ、Ｂｒ、Ｆ等が挙げられる。
これら式で表されるトリハロメチル−１，３，５−トリアジン化合物の具体例をCAS〔アメリカ化学会ケミカルアブストラクトサービス(Chemical Abstract Service)〕登録番号と共に下記に示す。
【００４３】

【００４４】
中でも好ましいハロメチル−１，３，５−トリアジン化合物は以下の通りである。

【００４５】
本発明の組成物におけるＤ成分の配合割合は、Ａ〜Ｃ成分の合計量に対して通常、０．０５〜３重量％、好ましくは０．１〜１．５重量％である。この割合が少なすぎると、得られる絶縁層は酸素などの周囲の環境の影響により感度が著しく低下するおそれがあり、一方、多すぎると、他の成分との相溶性に劣る上、塗膜表面における光吸収が大きくなって、硬化深度がとれない等の問題が生じることがある。
【００４６】
〔その他の成分または添加剤〕
本発明の感放射線組成物には、必要に応じて各種ゴム成分および溶剤や、接着助剤、充填材、着色剤、粘度調整剤、レベリング剤、消泡剤等の添加剤を添加することができる。
【００４７】
即ち、本発明の組成物には硬化物の接着性、強度、粗化面形成性などを補うために液状ゴム、架橋ゴム粒子などのゴム成分を添加することができる。このゴム成分は、Ａ〜Ｄ各成分との相溶性または親和性が高いことが必要である。この相溶性または親和性が低いゴム成分を用いると、得られる組成物に粘着性が生じたり、強度や粗化面形成性が不十分になるなどの問題が生じる可能性がある。
【００４８】
液状ゴムまたは架橋ゴム粒子としては、公知の各種合成ゴムを挙げることができるが、Ａ成分などに対して高い相溶性または親和性が得られることから、アクリルゴム（ＡＣＭ）、アクリロニトリル・ブタジエンゴム（ＮＢＲ）、アクリロニトリル・アクリレート・ブタジエンゴム（ＮＢＡ）が好ましく、さらに必要に応じて、エポキシ基、水酸基、カルボキシル基およびアミノ基より選ばれる少なくとも１種の官能基を有するものも使用することができる。実用上、エポキシ基またはカルボキシル基を有する合成ゴムが好ましく、特にカルボキシル基を有する合成ゴムが好ましい。
【００４９】
液状ゴムは公知のいかなる方法で製造されたものであってもよく、その製造には乳化重合、溶液重合、塊状重合、懸濁重合などの各種の方法を用いることができ、重合方式もバッチ式、回分式、連続式のいずれでもよい。こうして得られる液状ゴムにはイオン成分が含まれるが、液状ゴムとしては、イオン成分の含有量が少ないものが好ましく、これにより、高い電気絶縁性を有する絶縁層を形成することができる。液状ゴムを得るための単量体組成物にジエン系単量体が含有される場合には、この組成物の重合は乳化重合法によって容易に実施でき、特に特開昭６２−７４９０８号公報に示された方法に従って乳化重合を行えば、イオン成分の含有量の少ない液状ゴムを得ることができる。
【００５０】
一方、架橋ゴム粒子については、その粒径が１０ｎｍ〜１０００ｎｍの範囲にあるものが好ましく用いられる。
【００５１】
本発明の組成物には、組成物の塗布性、均一性等を向上するために、溶剤を添加することができる。溶剤としては、Ｎ−メチルホルムアミド、Ｎ，Ｎ−ジメチルホルムアミド、Ｎ−メチルホルムアニリド、Ｎ−メチルアセトアミド、Ｎ，Ｎ−ジメチルアセトアミド、Ｎ−メチルピロリドン、ジメチルスルホキシド、ベンジルエチルエーテル、ジヘキシルエーテル、アセトニルアセトン、イソホロン、カプロン酸、カプリル酸、１−オクタノール、１−ノナノール、ベンジルアルコール、酢酸ベンジル、安息香酸エチル、乳酸エチル、シュウ酸ジエチル、マレイン酸ジエチル、γ−ブチロラクトン、シクロヘキサノン、炭酸エチレン、炭酸プロピレン、フェニルセロソルブアセテート、メトキシメチルプロピオネート、エトキシエチルプロピオネート、ジエチレングリコールジメチルエーテル、ジエチレングリコールメチルエチルエーテル、トリエチレングリコールジメチルエーテル、トリエチレングリコールメチルエチルエーテルなどの高沸点溶剤が挙げられる。これら溶剤の割合は、組成物の用途や塗布方法に応じて変更することができ、組成物を均一な状態とすることができれば特に限定されるものではないが、得られる液状組成物に対し通常５〜６０重量％、好ましくは１０〜４０重量％である。
【００５２】
本発明の組成物には該組成物が適用される基板に対する接着性を向上させるために接着助剤を添加することができる。接着助剤としては、官能性シランカップリング剤が有効である。ここで、官能性シランカップリング剤とは、カルボキシル基、メタクリロイル基、イソシアネート基、エポキシ基などの反応性置換基を有するシランカップリング剤を意味し、その例としてはトリメトキシシリル安息香酸、γ−メタクリロキシプロピルトリメトキシシラン、ビニルトリアセトキシシラン、ビニルトリメトキシシラン、γ−イソシアナートプロピルトリエトキシシラン、γ−グリシドキシプロピルトリメトキシシラン、β−（３，４−エポキシシクロヘキシル）エチルトリメトキシシランなどを挙げることができ、その配合割合は、組成物１００重量部当たり２重量部以下が好ましい。
【００５３】
本発明の組成物には、その他、充填材、着色剤、粘度調整剤、レベリング剤、消泡剤等の添加剤を添加することができる。充填材としては、シリカ、アルミナ、タルク、炭酸カルシウム、ベントナイト、ジルコニウムシリケート、粉末ガラスなどを挙げることができる。着色剤としては、アルミナ白、クレー、炭酸バリウム、硫酸バリウムなどの体質顔料；亜鉛華、鉛白、黄鉛、鉛丹、群青、紺青、酸化チタン、クロム酸亜鉛、ベンガラ、カーボンブラックなどの無機顔料；ブリリアントカーミン６Ｂ、パーマネントレッド６Ｂ、パーマネントレッドＲ、ベンジジンイエロー、フタロシアニンブルー、フタロシアニングリーンなどの有機顔料；マゼンタ、ローダミンなどの塩基性染料；ダイレクトスカーレット、ダイレクトオレンジなどの直接染料；ローセリン、メタニルイエローなどの酸性染料、その他を挙げることができる。粘度調整剤としては、ベントナイト、シリカゲル、アルミニウム粉末などを挙げることができる。レベリング剤としては、各種シリコーン系化合物、ポリアルキレンオキシド系化合物などを挙げることができる。消泡剤としては、表面張力の低いシリコン系化合物、フッ素系化合物などを挙げることができる。これら添加剤の割合は、組成物の本質的な特性を損なわない範囲であり、具体的には組成物全体の５０重量％以下が適当である。
【００５４】
〔組成物の調製〕
本発明の組成物を調製するには、充填材、顔料を添加しない場合には各成分を通常の方法で混合、攪拌するだけでよく、充填材、顔料を添加する場合にはディゾルバー、ホモジナイザー、３本ロールミルなどの分散機を用いて分散、混合すればよい。また、必要に応じて、メッシュ、メンブレンフィルターなどを用いてろ過することもできる。
【００５５】
〔組成物の用法〕
本発明の組成物は、例えば多層配線板の製造における絶縁層の形成に使用される。本発明の組成物を用いて多層配線板を製造するには、表面に導体配線が形成された配線板の表面に、前記塗布法により本発明の組成物よりなる絶縁性薄膜を形成し、この薄膜に放射線による露光処理および現像液による現像処理を施すことにより、薄膜の非露光領域に例えば前記導体配線に至る貫通孔を形成し、これにより薄膜の非露光領域を導体配線が露出された状態とし、次にこの薄膜の表面に、前記導体配線と導通する新たな導体配線を形成するという一連の工程を１回行うか、または複数回繰り返せばよい。すなわち、表面にｎ番目の導体配線が形成された配線板の表面に、本発明の組成物を用いて絶縁層を形成し、次にこの絶縁層の表面に、ｎ番目（但し、ｎは１以上の整数）の導体配線と導通する（ｎ＋１）番目の導体配線を、めっき処理などによって形成する工程を１回行うか、または複数回繰り返せばよい。
【００５６】
以下に、本発明の組成物を用いて多層配線板を製造する方法について、工程順に更に詳しく説明する。
（１）薄膜形成工程
この薄膜形成工程においては、例えば基板表面に導体配線を形成してなる配線板の表面に、前記導体配線が覆われるように本発明の組成物を塗布し、次いで塗布面を加熱、乾燥して組成物中の溶剤を除去することにより薄膜を形成する。
【００５７】
ここで、導体配線が形成される基板の材質は特に限定されるものでなく、例えばガラスエポキシ樹脂、紙フェノール樹脂、セラミック、ガラス、シリコンウエハなどを挙げることができる。また、塗布方法も特に限定されるものではなく、一般的な感光性材料の塗布方法を利用することができる。具体的には、スクリーン印刷、ロールコーティング、バーコーティング、ディップコーティング、カーテンコーティング、スピンコーティング、アプリケーター法などの方法を挙げることができる。また、本発明の組成物を基体フィルム上に流延、製膜し、乾燥させて、いわゆるドライフィルムを作製し、これをラミネーターなどによって基板に貼り合わせることにより薄膜を形成してもよい。この場合、基体フィルムとしては、透光性のあるものが好ましく、このような透光性フィルムとしては、例えばポリエチレンテレフタレート、ポリブチレンテレフタレートなどのポリエステル系フィルム；延伸ポリプロピレン、ポリスチレンなどのポリオレフィン系フィルムを使用することができる。なお、基体フィルムが透光性フィルムである場合は、基体フィルムを通して露光することにより、前記薄膜を光硬化させることが可能である。
【００５８】
塗布後の乾燥条件は、組成物を構成する各成分の種類および配合割合、並びに膜厚などによっても異なるが、通常７０〜１３０℃の温度で５〜２０分間程度である。この薄膜の乾燥は、オーブンやホットプレートなどの通常の装置を用いて行われる。なお、乾燥が不十分であると、残留する溶剤によって薄膜の表面にべとつきが生じ、また、基板に対する絶縁層の密着性が低下することがあり、一方、乾燥が過度であると、熱かぶりによって解像性の低下を招くことがある。
【００５９】
こうして形成される薄膜の乾燥後の膜厚は、通常１０〜１００μｍ、好ましくは３０〜７０μｍである。膜厚が過小であると、十分な絶縁性を有する絶縁層を形成できないことがあり、一方、膜厚が過大であると解像性の低下を招くことがある。
【００６０】
（２）露光処理工程
この露光処理工程においては、薄膜形成工程によって配線板上に形成された薄膜に、所定のパターンを有するマスクを介して、放射線、例えば波長２００〜５００ｎｍの紫外線または可視光線を照射することにより、薄膜の光照射領域（露光領域）を光硬化させる。露光処理装置としては、フュージョン、コンタクトアライナー、ステッパー、ミラープロジェクターなどを使用することができる。また放射線光源としては、例えば低圧水銀灯、高圧水銀灯、超高圧水銀灯、メタルハライドランプ、アルゴンガスレーザ、Ｘ線発生装置、電子線発生装置などを挙げることができる。薄膜に対する露光量は、薄膜を構成する組成物における各成分の種類および配合割合、並びに膜厚などによっても異なるが、例えば高圧水銀灯を使用する場合は１００〜５００ｍＪ／ｃｍ² である。
【００６１】
（３）硬化促進用加熱工程
この硬化促進用加熱工程においては、露光処理工程後の薄膜を、通常、温度７０〜１３０℃で３〜６０分間程度加熱し、これにより露光処理工程における光反応による硬化に加えて、熱反応による薄膜の硬化を促進させる。この加熱工程は、オーブンやホットプレートなどの通常の装置を用いて行われる。なお、この加熱が過度であると、熱かぶりによって解像性の低下を招くことがある。
【００６２】
（４）現像処理工程
この現像処理工程においては、非露光領域における組成物を、アルカリ水溶液よりなる現像液に溶解させて除去し、露光領域における硬化組成物のみを残存させることにより、パターン形成を行う。
【００６３】
ここで、現像液としては、例えば水酸化ナトリウム、水酸化カリウム、炭酸ナトリウム、ケイ酸ナトリウム、メタケイ酸ナトリウム、アンモニア、エチルアミン、ｎ−プロピルアミン、ジエチルアミン、ジ−ｎ−プロピルアミン、トリエチルアミン、メチルジエチルアミン、ジメチルエチルアルコールアミン、トリエチルアルコールアミン、テトラメチルアンモニウムヒドロキシド、テトラエチルアンモニウムヒドロキシド、ピロール、ピペリジン、１，８−ジアザビシクロ〔５．４．０〕−７−ウンデセン、１，５−ジアザビシクロ〔４．３．０〕−５−ノナンなどのアルカリ化合物の水溶液を用いることができる。また、上記のアルカリ類の水溶液にメチルアルコール、エチルアルコールなどの水溶性有機溶剤や界面活性剤を適当量添加した水溶液、または本発明の組成物を溶解する各種有機溶剤を現像液として使用することができる。好ましい現像液は、水酸化ナトリウム、水酸化カリウム、炭酸ナトリウム、テトラメチルアンモニウムヒドロキシドなどの、濃度０．１〜３．０重量％、特に好ましくは０．５〜１．５重量％の水溶液である。
【００６４】
現像方法としては、液盛り法、ディッピング法、パドル法、スプレー現像法などを挙げることができる。現像処理後には、例えば流水洗浄を３０〜９０秒間行い、エアーガンなどを用いてあるいはオーブン内において乾燥させる。
この現像処理工程によって薄膜の一部が除去されて、例えば貫通孔が形成され、基板表面の導体配線の一部が露出される結果、フォトビアホールを有する絶縁層が形成される。
【００６５】
（５）熱硬化および／または後露光工程
本発明の組成物は光硬化性および熱硬化性の両方の性質を有しており、現像処理後、この熱硬化および／または後露光工程を行なうことにより、フォトビアホールを有する絶縁層の硬化が更に促進される。従って、この熱硬化および／または後露光工程は、絶縁層が十分な硬化状態にある時は不要の工程である。熱硬化工程は、ホットプレート、オーブン、赤外線オーブンなどを用いて、絶縁層が熱劣化を起こさない温度条件、好ましくは１５０〜１８０℃で３０分間〜５時間程度の適当な時間が選択されて行われる。また、後露光工程は、露光処理工程で使用されるものと同様の光源および装置を用いて、例えば１００〜１，０００ｍＪ／ｃｍ² の露光量で行なわれる。
【００６６】
（６）平坦化処理工程
この平坦化処理工程は、例えば平坦でない基板上に形成された絶縁層を研磨処理によって平坦化するための任意の工程であり、絶縁層を平坦化することによって、絶縁層の表面に導体配線を形成する場合に回路加工の精度を向上させることができる。ここで、研磨手段としては、例えばバフロール、ナイロンブラシ、ベルトサンダーなどが使用できる。
【００６７】
（７）スルーホール形成工程
このスルーホール形成工程は、部品の挿入や他の配線板との接続、すなわち層間接続を達成するためにスルーホールが必要とされる場合において、数値制御型ドリルマシンなどを用いて機械的に穿孔加工を行う工程である。なお、本発明の組成物を用いた多層印刷版の製造方法では、フォトビアホールによって層間接続を行うことができるので、このスルーホール形成工程は必要がある場合にのみ行われる任意の工程である。
【００６８】
（８）粗面化処理工程
この粗面化処理工程は、上記の絶縁層の表面に形成される導体配線の密着性を向上させるために、絶縁層の表面を粗面化処理液によって粗面化する工程である。
粗面化処理液としては、過マンガン酸カリウム水溶液、過マンガン酸カリウムと水酸化ナトリウムとの水溶液などのアルカリ性の処理液、無水クロム酸と硫酸との混酸、その他の強酸化性を有するものが用いられる。これらのうち、過マンガン酸カリウムと水酸化ナトリウムとの水溶液が特に好ましい。粗面化処理を行うには、５０〜８０℃の温度に維持した処理液中に５〜３０分間、絶縁層を浸漬すればよい。なお、粗面化処理後には、必要に応じて絶縁層表面をシュウ酸などの弱酸水溶液で中和した後、流水洗浄を十分に行うことが必要である。
【００６９】
この粗面化処理工程によって、絶縁層の表面、フォトビアホールの側壁面およびスルーホールの側壁面は、０．０１〜１０μｍの凹凸形状を有する粗面状態となり、粗面化のアンカー効果によって導体配線を構成する銅めっき層に対して強固な密着力が発揮される。
【００７０】
（９）触媒処理工程
この触媒処理工程は、絶縁層の表面およびホールの内壁表面に、次工程において無電解銅めっき処理を行う際の析出核となるめっき触媒を担持させる工程である。ここで、めっき触媒としては、例えばパラジウムなどの金属コロイドを使用することができる。このような金属コロイドを媒体中に分散してなる各種公知の処理液中に絶縁層を浸漬させることにより、触媒の担持処理は達成される。なお、本発明の組成物中にはめっき触媒を含有させることができ、この場合には、この工程を省略することができる。
【００７１】
（１０）新たな導体配線の形成工程
この新たな導体配線の形成工程は、例えば無電解銅めっき処理を行うことにより、フォトビアホールおよびスルーホールを介して、基板表面に既に形成されている導体配線（第１の導体配線）との電気的接続を実現しながら、絶縁層の表面に新たな導体配線（第２の導体配線）を形成する工程である。新たな導体配線の形成方法としては、例えば以下に示す方法▲１▼〜▲３▼を挙げることができる。
【００７２】
方法▲１▼：
触媒が担持された絶縁層表面の全域に無電解銅めっき処理を行って銅めっき層を形成し、必要に応じて、この銅めっき層を電極とする電解銅めっき処理により所望の厚みを有する銅金属層を形成し、この銅金属層上にレジストパターンを形成し、次いで銅金属層をエッチングして導体パターンを形成する。ここで、レジストパターンは、第２の導体配線が形成される領域の他に、第１の導体配線と第２の導体配線との間の層間接続用導体が形成される層間接続用フォトビアホールの位置、すなわち導体ランドが形成されるべき領域にも形成される。この導体ランドの径は、位置ずれ誤差を考慮してフォトビアホールの径よりも大きくすることが好ましい。レジストパターンは、通常、フォトレジストを用いたフォトリソグラフィーによって形成される。また、銅金属層のエッチングは、過硫酸アンモニウム水溶液やアンモニア錯体系のエッチング液により行われる。銅金属層のエッチングを行った後、レジストパターンを所定の方法で剥離除去する。フォトレジストは、必要な解像性およびエッチング液に対する耐性を有し、後に除去できるものであればよい。このようにして、基板の表面の第１の導体配線と導通する第２の導体配線が絶縁層の上に形成される。
【００７３】
方法▲２▼：
触媒が担持された絶縁層表面において新たな導体配線を形成すべき領域以外の領域にレジストパターンを形成した後、無電解銅めっき処理および必要に応じて電解銅めっき処理を行うことにより、絶縁層表面において新たな導体配線を形成し、且つフォトビアホールの内壁表面に銅めっき層を形成し、次いでレジストパターンを剥離除去する。この方法においても、導体配線の幅をフォトビアホールの径よりも大きくすることが好ましい。
【００７４】
方法▲３▼：
触媒が担持された絶縁層の表面全体に、めっき触媒を含有しない感光性樹脂組成物を塗布して被膜を形成し、この被膜をパターンマスクを介して露光し、次いで現像することにより、この被膜にフォトビアホールを形成すると共に、これに連続する第２の導体配線となる個所の被膜部分を除去し、その上で無電解銅めっきのみを行う。この方法においても、導体配線の幅をフォトビアホールの径よりも大きくすることが好ましい。また、被膜の厚さは、銅めっきによる銅金属層の厚さと同じかやや大きめであることが好ましい。
【００７５】
この方法によれば、形成される第２の導体配線は、被膜の除去部分に形成されると共に、残存被膜からなる絶縁膜が元の絶縁層の上に残存し、しかもこの残存被膜と銅金属層の厚さが通常近似しているため、平坦性に優れた外表面を得ることができる。
なお、以上の被膜を形成するための感光性樹脂組成物としては、本発明の組成物を用いることができる。
【００７６】
以上の工程（１）〜（１０）を繰り返すことにより、さらに多層化することができる。この場合、新たな導体配線の形成工程（１０）を実施する際に方法▲１▼〜▲３▼を組み合わせて多層化することもできる。
【００７７】
なお、多層配線板の最上層となる絶縁層の表面に導体配線を形成した後、絶縁層と導体配線との密着性を向上させる観点から、ポストベークを行うことが好ましい。最上層以外の絶縁層およびこの絶縁層に係る導体配線に対しては、その後の絶縁層の形成における加熱工程において加熱されるため、特に単独の工程としてポストベークを行う必要はない。
【００７８】
【実施例】
以下、本発明を実施例によって具体的に説明するが、本発明はこれらに限定されるものではない。また、特に明示する場合を除き、「部」は「重量部」を、「％」は「重量％」を示す。
〔Ａ成分〕次の４種を用意した。
【００７９】
Ａ１：クレゾールノボラック樹脂〔ｍ−クレゾール：ｐ−クレゾール＝６：４（モル比）、重量平均分子量Ｍｗ＝１１，０００〕
Ａ２：フェノールノボラック樹脂〔重量平均分子量Ｍｗ＝６０００〕
Ａ３：ポリ（ｐ−ビニルフェノール）〔丸善石化社製、重量平均分子量Ｍｗ＝３，０００〕
Ａ４：ポリ（臭素化ｐ−ビニルフェノール）〔丸善石化社製「マルカリンカーＭＢ」、重量平均分子量Ｍｗ＝４,０００〕
〔Ｂ成分〕次のアミノ樹脂３種を用意した。
【００８０】
Ｂ１：ヘキサメトキシメチル化メラミン〔三井サイテック社製「サイメル３００」〕
Ｂ２：テトラメトキシメチル化グリコールウリル〔三井サイテック社製「サイメル１１７０」〕
Ｂ３：ベンゾグアナミン樹脂〔三和ケミカル社製「ＢＸ−４０００」〕
〔Ｃ成分〕
Ｃ１：ビスフェノールＡ型エポキシ樹脂（油化シェルエポキシ社製、エピコート８２８）
Ｃ２：ノボラック型エポキシ樹脂（日本化薬社製、ＥＯＣＮ−１００）
Ｃ３：２，２‘−[（１−メチルエチリデン）ビス（４，１−フェニレンオキシメチレン）]ビスチイラン
Ｃ４：１，４−ビス[（３−エチル−３−オキセタニルメトキシ）メチル]ベンゼン
〔Ｄ成分〕次の光重合開始剤３種を用意した。
【００８１】
Ｄ１：２，４−トリクロロメチル−（４’−メトキシフェニル）−６−トリアジン
Ｄ２：２，４−トリクロロメチル−（４’−メトキシスチリル）−６−トリアジン
Ｄ３：ジフェニルヨードニウム−９，１０−ジメトキシアントラセンスルホネート
Ｄ４：トリフェニルスルホニウムヘキサフルオロフォスフェート
【００８２】
〔添加剤〕
Ｅ：ブタジエン−アクリロニトリル−メタクリル酸共重合体〔ブタジエン：アクリロニトリル：メタクリル酸＝６０：３５：５（モル比）、数平均分子量Ｍｎ＝６，０００、ガラス転移点Ｔｇ＝−３９℃〕
〔溶剤〕次の有機溶剤２種を用意した。
【００８３】
ＭＭＰ：３−メトキシプロピオン酸メチル
ＰＧＭＥＡ：プロピレングリコールモノメチルエーテルアセテート＜実施例１〜７、比較例１〜４（組成物の調製）＞
下記表１に示す処方に従って、上記のＡ〜Ｄ成分、並びに必要に応じて添加剤および溶剤を配合し、得られた配合物の各々を、ヘンシェルミキサーにより混合・攪拌を行うことにより、感放射線性樹脂組成物を調製した。
【００８４】
【表１】

【００８５】
＜組成物および絶縁層の性能評価、並びに多層配線板の製造＞
（１）感光特性評価テスト基板の作製および評価
銅金属層が一面に形成されたガラスエポキシ樹脂よりなる板状体をテストピースとして用い、前記面上に、実施例１〜７および比較例１〜４で調製された組成物の各々をスピンコータを用いて塗布し、熱風オーブン内において９０℃で１０分間乾燥することにより、乾燥後の膜厚が約５０μｍの薄膜を形成した。
【００８６】
こうして得られたテストピースの各々について、その薄膜に対し、直径が各々２５μｍ、５０μｍ、７５μｍ、１００μｍ、１５０μｍまたは２００μｍの穿孔パターンが形成されたテスト用ガラスマスクを介して露光を行った。露光処理は、コンタクトアライナー（ミカサ電機社製「ＭＬ−３型」）を用い、コンタクト（密着露光）で１，０００ｍＪ／ｃｍ² の露光量で行った。
【００８７】
露光処理後のテストピースを１２０℃で５分間加熱処理した後、０．７５％のテトラメチルアンモニウムヒドロキシド水溶液中に１８０〜３００秒間浸漬して揺動させることにより現像処理を行い、銅金属層に至る貫通孔、すなわちフォトビアホールを有する絶縁層を形成した。その後、この絶縁層が形成されたテストピースの各々を水洗し乾燥した。この時、直径７５μｍの貫通孔が完全に形成されたものを良好、それ以外のものを不良として現像性を評価した。
【００８８】
次に、絶縁層が形成されたテストピースの各々を、熱風オーブン内において温度１５０℃で６０分間加熱することにより硬化させ、その後、熱硬化したテストピースを、６５℃の温度に維持された過マンガン酸カリウム−水酸化ナトリウム水溶液（過マンガン酸カリウム濃度３％、水酸化ナトリウム濃度２％）中に１０分間浸漬することにより、絶縁層の表面に対して粗面化処理を行い、その後、テストピース表面を濃度５％のシュウ酸水溶液中に室温で５分間浸漬することにより中和処理し、さらに十分に水洗した。
【００８９】
このテストピースの各々について、絶縁層の表面状態を走査型電子顕微鏡により観察してその粗面化処理の状態を評価した。評価の方法は、絶縁層表面が十分に粗面化されて微細な凹凸が形成されている場合を「良好」とし、それ以外を「不良」とした。
【００９０】
また、テストピースの各々を塩化パラジウム系の触媒液中に室温で６分間浸漬することにより、粗面化された絶縁層の表面および貫通孔の内面にめっき触媒を担持させ、さらに触媒活性化液中に室温で８分間浸漬して、めっき触媒を活性化させた。その後、テストピースの各々を水洗した後、室温で２０分間にわたって無電解銅めっき処理を行った。この処理では、触媒液、触媒活性化液および無電解銅めっき液として「ＯＰＣプロセスＭシリーズ」（奥野製薬（株）製）のものを用いた。次に、硫酸銅−硫酸水溶液（硫酸銅濃度２１０ｇ／Ｌ、硫酸濃度５２ｇ／Ｌ、ｐＨ＝１．０）よりなる電解銅めっき液を用い、３．０ｍＡ／ｄｍの電流密度で電解銅めっき処理を行い、合計の厚みが約２０μｍの銅金属層を絶縁層の表面全体にわたって形成し、その後、このテストピースを１５０℃で１時間加熱処理した。
【００９１】
これらのテストピースの表面に１ｃｍ間隔の切り込みを形成し、端面からピールテスターで剥離させることにより、銅金属層のピール強度（ＪＩＳ Ｃ ６４８１）を測定した。このピール強度は、１０ｃｍ引き剥がした中での最頻値であり、８００ｇ／ｃｍ以上の強度を示したものを合格とした。
【００９２】
（２）耐電食性の評価
１００μｍ配線ピッチの電食評価用櫛形電極基板〔ＢＴ（ビスマレイミドトリアジン）レジン製、１０×１０ｃｍ角〕上に５０μｍ膜厚の絶縁層を（１）感光特性評価テスト基板の作製および評価方法に準じて形成し、電食評価用基板を作成した。この電食評価用基板を８５℃×８５％ＲＨの恒温恒湿槽に入れ、基板に１００Ｖの直流電流を継続的に印可しながら、その絶縁抵抗値を記録した。絶縁抵抗が１０⁸ohmを切るまでの時間を求め、耐電食時間（ｈｒ）とした。
以上の結果を表２に示す。この表から明らかなように、実施例１〜７は、何れも現像性、粗面状態、ピール強度等の性能が良好であり、かつ耐電食時間が長く、耐電食性に優れていた。一方、比較例１〜４は、現像性、粗面状態、ピール強度等の性能は良好であるが、耐電食性に劣っていた。即ち、本発明の組成物は現像性、粗面状態、ピール強度等の諸性能を落とさずに耐電食性が向上したことが判る。
【００９３】
【表２】

【００９４】
【発明の効果】
本発明に係る感放射線性樹脂組成物は、アルカリ可溶性フェノール樹脂およびアミノ樹脂と共に、１分子中にエポキシ基、オキセタニル基、チラニイル基またはビニルエーテル基等の架橋性基を複数有する化合物を必須成分として含有することにより、特に多層配線板の製造において、例えば小径のフォトビアホールを高い精度で且つ形成することができる優れた解像性を有し、アルカリ水溶液により現像することができ、耐めっき液性および導体配線の密着性に優れ、また硬化後は良好な耐溶剤性、耐水性および耐熱性を有する絶縁層を形成することができる。従って本発明の組成物を使用することにより、電気絶縁信頼性の高い多層配線板を効率よく製造することができる。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a radiation-sensitive resin composition, and in particular, in the production of a multilayer wiring board, a radiation-sensitive resin composition suitable as a material for forming an insulating layer interposed between two conductor wirings arranged in a stacked manner. About.
[0002]
[Prior art]
In recent years, due to the demand for higher density in printed wiring boards, the importance of multilayer wiring boards having a configuration in which a plurality of wiring boards on which conductor wirings are formed is stacked via an insulating layer is increasing. As a method for manufacturing such a multilayer wiring board, after forming an insulating layer on the surface of the wiring board on which the conductor wiring is formed, a process of forming another conductor wiring that is electrically connected to the conductor wiring on the insulating layer A method of repeating (also called “stacking method”) has been proposed. In the case of this multilayer wiring board manufacturing method, through holes (through holes) are formed in the same manner as in the case of the laminated press method in order to make two conductor wirings stacked through an insulating layer conductive. In addition to the method of plating the wall surface, a method of forming a hole called a via hole penetrating only a part of the insulating layer with a drill and plating the inner wall surface is performed.
[0003]
As a method for forming a through hole or a via hole in an insulating layer, a method using an excimer laser, a method of forming a predetermined pattern using a processing resist, and etching the insulating layer with an appropriate solvent are known. Yes. However, these methods are not preferable from the viewpoint of productivity because a plurality of holes cannot be formed at the same time or many steps are required. Further, each of the above methods is not a satisfactory method from the viewpoint of processing accuracy.
[0004]
Therefore, a method has been proposed in which a photosensitive resin composition is used as a material for forming an insulating layer interposed between a plurality of conductor wirings, and through holes are formed in the insulating layer by photolithography. According to this method, since a plurality of through-holes can be formed simultaneously, high production efficiency can be obtained in the manufacture of a multilayer wiring board, and the through-holes can be formed with higher accuracy than conventional methods. This is advantageous in producing a multilayer wiring board having a fine wiring pattern. In addition, the through-hole formed in the insulating layer which consists of a photosensitive resin composition, and achieving an electrical connection later by a plating process is called the photo via hole.
[0005]
Japanese Patent Application Laid-Open No. 5-273653 proposes an application example using a phenol resin, an amino resin, an epoxy resin, and an onium salt as a photosensitive resin composition for forming such an insulating layer.
[0006]
According to the method for producing a multilayer wiring board by using a photosensitive resin composition for forming an insulating layer and by a stacking method, a multilayer laminated structure can be obtained without performing a pressing process, and a sufficiently small diameter can be obtained by photolithography. Since the photo via hole can be formed with high accuracy, a multilayer wiring board having a fine wiring pattern can be suitably manufactured.
[0007]
The following performance is required for a photosensitive resin composition used for forming an insulating layer when a multilayer wiring board is manufactured by a stacking method.
(1) The obtained insulating layer has excellent resolution. Thereby, the small diameter photo via hole according to the fine pattern can be formed with high accuracy and high density.
(2) The obtained insulating layer has a sufficiently high resistance (plating solution resistance) to, for example, an electroless copper plating solution used for forming a conductor wiring, and has good solvent resistance after curing. And have water resistance.
(3) The insulating layer obtained should be capable of forming conductor wiring on its surface with sufficient adhesion by, for example, electroless copper plating. Here, in order to improve the adhesion of the conductor wiring by copper plating, it is effective that the surface of the insulating layer is roughened. In the insulating layer having a roughened surface, the rough surface Due to the anchor effect, the adhesion of the conductor wiring to the insulating layer is increased.
(4) An alkaline aqueous solution can be used as a developing solution for forming a photo via hole. If alkaline aqueous solution can be used as a developing solution, the bad influence on a human body and an environment can be suppressed.
(5) The obtained insulating layer has sufficient electrical insulation, and therefore high reliability is obtained with respect to electrical insulation, and has high heat resistance after curing. This makes it possible to advantageously apply to the manufacture of electronic devices that are being reduced in size and weight.
[0008]
However, it has been impossible to form an insulating layer that satisfies all of the above performances with conventional photosensitive resin compositions.
For example, the photosensitive resin composition proposed in Japanese Patent Application Laid-Open No. 5-273533 is excellent in alkali developability, resolution, and adhesion of conductor wiring by copper plating as an insulating layer, but generates photoacid. The onium salt used as an agent has a problem that it has a considerable adverse effect on long-term electrical insulation reliability.
[0009]
[Problems to be solved by the invention]
The object of the present invention is, in particular, in the production of multilayer wiring boards, has excellent resolution, excellent plating solution resistance and adhesion of conductor wiring, can be developed with an alkaline aqueous solution, and has good solvent resistance after curing. It is an object of the present invention to provide a radiation-sensitive resin composition capable of forming an insulating layer having heat resistance, water resistance and heat resistance, and thus efficiently producing a multilayer wiring board having high electrical insulation reliability.
[0010]
[Means for Solving the Problems]
As a result of intensive studies to solve the above-described problems in the prior art, the present inventors have found that a radiation-sensitive resin composition containing the following components A to D achieves the above object. The present invention has been reached.
[Component A] Phenolic resin
[Component B] Amino resin
[Component C] Compound having a plurality of crosslinkable groups in one molecule
[Component D] Halomethyl-1,3,5-triazine compound
In particular, it has been found that the electrical insulation reliability after curing is dramatically improved by combining the A to C components and the halomethyl-1,3,5-triazine compound, which is the D component, as the activating radiation compound.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the radiation sensitive resin composition of the present invention will be described in detail.
The radiation-sensitive resin composition of the present invention generates a free acid in which the halomethyl-1,3,5-triazine compound of D component is a curing catalyst by irradiation with activating radiation, and further, 80 to 120 ° C. as necessary. Is heated, and at the same time, the crosslinking reaction between the A component phenolic resin and the B component amino resin starts, and at the same time, the cationic polymerization of the compound having a plurality of crosslinkable groups as the C component starts. The exposed area is cured, resulting in a difference in solubility in alkaline developer between the exposed and non-exposed areas, forming a latent pattern. Furthermore, after this latent pattern is developed, it is cured at a temperature of 120 ° C. or higher to cause a crosslinking reaction between the A component phenolic resin and the unreacted C component compound having a crosslinkable group. A cured product having excellent resistance to chemicals such as solvents, water resistance and heat resistance can be obtained.
[0012]
[Component A]
The component A phenol resin is an arbitrary polymer having a phenolic hydroxyl group such as a phenol group or a xylenol group in the molecule, and is used as a base polymer. Specific examples of this phenol resin include polyvinyl phenol and novolac resin. Examples of polyvinylphenol include those obtained by polymerizing vinylphenol monomers in a conventional manner, or those obtained by polymerizing in a state in which a phenolic hydroxyl group is protected with a protecting group, and then removing the protecting group. The thing obtained by various manufacturing methods can be mentioned. Further, it is obtained from a monomer in which various substituents are introduced into the vinylphenol monomer, such as vinylcresol, 2,4-dimethylvinylphenol, fluorinated vinylphenol, chlorinated vinylphenol, brominated vinylphenol and the like. Various substituted polyvinylphenols can also be used.
[0013]
The molecular weight of the polyvinylphenol is not particularly limited, but the weight average molecular weight is 2,000 or more, particularly 2,000 to 2,000 from the viewpoints of resolution, developability, plating solution resistance, etc. in the obtained insulating layer. It is preferably in the range of 40,000.
[0014]
On the other hand, the novolak resin contains, for example, an aromatic compound having a phenolic hydroxyl group (hereinafter referred to as “phenols”) and an aldehyde, and preferably a ratio of 0.7 to 1 mol of aldehyde with respect to 1 mol of phenol. It can be obtained by addition condensation using an acid catalyst. Here, specific examples of phenols include phenol, o-cresol, m-cresol, p-cresol, o-ethylphenol, m-ethylphenol, p-ethylphenol, o-butylphenol, m-butylphenol, p- Butylphenol, 2,3-xylenol, 2,4-xylenol, 2,5-xylenol, 2,6-xylenol, 3,4-xylenol, 3,5-xylenol, 3,6-xylenol, 2,3,5- Trimethylphenol, 3,4,5-trimethylphenol, p-phenylphenol, resorcinol, hydroquinone, hydroquinone monomethyl ether, pyrogallol, phloroglucinol, hydroxydiphenyl, bisphenol A, gallic acid, gallic acid ester, α-naphthol, β- Naftou And the like.
[0015]
Specific examples of aldehydes include formaldehyde, paraformaldehyde, furfural, benzaldehyde, nitrobenzaldehyde, acetaldehyde and the like. As the acid catalyst, for example, hydrochloric acid, nitric acid, sulfuric acid, formic acid, oxalic acid, acetic acid and the like are used.
[0016]
The novolak resin needs to have a weight average molecular weight of 200 or more from the viewpoint of the resolution, developability, plating solution resistance, and the like of the obtained insulating layer, and particularly those in the range of 400 to 2,000. preferable.
[0017]
The proportion of the component A in the composition of the present invention is such a proportion that the obtained insulating layer exhibits sufficient alkali solubility, specifically, usually 30 to 75 weights with respect to the total amount of the components A to C. %, Preferably 40 to 70% by weight. If this ratio is too small, the unexposed portion of the resulting insulating layer does not exhibit sufficient developability with an alkaline aqueous solution, whereas if this ratio is excessive, the ratio of other components is relatively limited. As a result, the unexposed part of the resulting insulating layer may be insufficient in toughness, heat resistance and plating solution resistance.
[0018]
[B component]
The B component amino resin is a component having a plurality of active methylol groups in one molecule and acting as a curing agent that reacts with the A component alkali-soluble phenol resin to form a crosslinked structure.
Such amino resins include a plurality of active methylol groups in one molecule such as (poly) methylolated melamine, (poly) methylolated glycoluril, (poly) methylolated benzoguanamine, and (poly) methylolated urea. A nitrogen-containing compound having: a compound in which the hydrogen atom of the hydroxyl group of the methylol group in the nitrogen-containing compound is substituted by an alkyl group such as a methyl group or a butyl group; and the nitrogen-containing compound or a substituted compound thereof is partially self-condensed The compound containing an oligomer component is mentioned. These amino resins can be used alone or in admixture of two or more.
[0019]
Examples of commercial products of these amino resins include Cymel series products such as Cymel 300 (hexamethoxymethylated melamine) and Cymel 1170 (tetrabutoxymethylated glycoluril) manufactured by Mitsui Cyanamid Co., Ltd., and Mycoat series products. There are UFR series products, but among them, Cymel 300 hexamethoxymethylated melamine is preferable.
[0020]
The proportion of the B component as described above needs to be such a proportion that the obtained insulating layer is sufficiently cured by the action of the photopolymerization initiator and heat, specifically, with respect to 100 parts by weight of the A component. 10 to 60 parts by weight, preferably 15 to 50 parts by weight. If this ratio is too small, the resulting insulating layer may be insufficient in toughness, heat resistance and plating solution resistance. On the other hand, if this ratio is excessive, a thin film of the resulting composition will be sufficiently developed. There is a risk that it will not have the property.
[0021]
[C component]
Component C is a compound having a plurality of crosslinkable groups in one molecule, and examples of the crosslinkable group include an epoxy group, a thiranyl group, an oxetanyl group, and a vinyl ether group. Therefore, the compound of component C is specifically an epoxy compound, an oxetane compound, a thiirane compound or a vinyl ether compound. A mixture thereof can also be used as the C component. When the composition is exposed to activating radiation, the component C has a function of cationic polymerization to cure the exposed region and also to crosslink with heat during post-baking to give an insulating layer having high heat resistance.
[0022]
Epoxy compound
The epoxy compound is a compound having two or more epoxy groups in the molecule, and may have a functional group other than the epoxy group, and its molecular weight is not particularly limited, but is usually 70 to 20,000. is there.
Such epoxy compounds include glycidyl acrylate, glycidyl methacrylate, 3,4-epoxycyclohexyl acrylate, 3,4-epoxycyclohexyl methacrylate, polymers thereof, and these epoxy compounds and other polymerizable monomers (for example, Styrene, methyl methacrylate, hydroxyethyl methacrylate, butadiene, butyl acrylate, etc.); and various epoxy resins.
[0023]
Among these epoxy compounds, an epoxy resin is preferable, and examples thereof include glycidyl ether type epoxy resins represented by bisphenol type epoxy resin, novolak type epoxy resin, cresol novolak type epoxy resin, and the like; glycidyl ester type epoxy resin Aromatic glycidylamine type epoxy resins; alicyclic epoxy resins; heterocyclic epoxy resins; liquid rubber-modified epoxy resins.
[0024]
Oxetane compounds
The oxetane compound is a compound having two or more oxetanyl groups in the molecule, and examples thereof include compounds represented by the following formula (A), formula (B) and formula (C).
[0025]
[Chemical 1]

[0026]
[In each of the formulas (A), (B) and (C),
R¹Is an alkyl group such as a methyl group, an ethyl group, or a propyl group,
R²Is an alkylene group such as methylene group, ethylene group, propylene group,
R^ThreeIs an alkyl group such as a methyl group, an ethyl group, a propyl group, or a hexyl group; an aryl group such as a phenyl group or a xylyl group;
[0027]
[Chemical 2]

[0028]
(Where x is an integer from 0 to 50)
A dimethylsiloxane residue represented by R²An alkylene group, a phenylene group, or groups represented by the following formulas (1) to (5) as exemplified above for
[0029]
[Chemical 3]

(Where y is an integer from 1 to 50),
[0030]
[Formula 4]

(Where x is a single bond or —CH₂-, -C (CH_Three)₂-, -C (CF_Three)₂-Or -SO₂-Is a divalent group represented by
[0031]
[Chemical formula 5]

n is R^ThreeIs an integer of 1 to 4. ]
[0032]
Specific examples of the compounds represented by these formulas (A) to (C) include bis [(3-ethyl-3-oxetanylmethoxy) methyl] benzene (trade name “XDO” manufactured by Toagosei Co., Ltd.), bis [ (3-ethyl-3-oxetanylmethoxy) methyl-phenyl] methane, bis [(3-ethyl-3-oxetanylmethoxy) methyl-phenyl] ether, bis [(3-ethyl-3-oxetanylmethoxy) methyl-phenyl] Propane, bis [(3-ethyl-3-oxetanylmethoxy) methyl-phenyl] sulfone, bis [(3-ethyl-3-oxetanylmethoxy) methyl-phenyl] ketone, bis [(3-ethyl-3-oxetanylmethoxy) Methyl-phenyl] hexafluoropropane, tri [(3-ethyl-3-oxetanylmethoxy) methyl] be Zen, can be mentioned tetra [(3-ethyl-3-oxetanylmethoxy) methyl] benzene, and compounds represented by the following chemical formula (D) ~ (H).
[0033]
[Chemical 6]

[0034]
In addition to the above, compounds having a high molecular weight polyvalent oxetane ring can also be used, and specific examples thereof include, for example, oxetane oligomers (trade name “Oligo-OXT” manufactured by Toagosei Co., Ltd.) and the following chemical formulas (I) to (I): Examples thereof include compounds represented by (K).
[0035]
[Chemical 7]

(In these formulas, p, q and s are integers of 1 to 10,000.)
[0036]
Thiirane compounds
The thiirane compound is a compound having two or more thiranyl groups in the molecule, and may have a functional group other than thiranyl group, and its molecular weight is not particularly limited, but is usually 70 to 20,000. . The thiirane compound is generally synthesized by substituting the oxygen atom of the oxirane ring in the oxirane compound with a sulfur atom. For example, thiocyanate is used by the method shown in JMCharlesworth J. Polym. Sc. Polym. Phys. 17 329 (1979), or RD Schuetz et al., J. Org. Chem. 26 3467 (1961). It can synthesize | combine using thiourea by the method shown by these. A synthesis method from a cyclic carbonate is also shown in S.Seales et al. J. Org. Chem., 27 2832 (1962) and the like. Synthesizeable thiirane compounds are shown in Table-I in M. Sander, Chem. Rev. 66 297 (1966). Specific examples of the present invention include glycidyl acrylate, glycidyl methacrylate, 3,4 -Epoxycyclohexyl acrylate, 3,4-epoxycyclohexyl methacrylate, and polymers of these epoxy compounds or these epoxy compounds and other polymerizable monomers (for example, styrene, butadiene, methyl methacrylate, butyl acrylate, hydroxyethyl methacrylate, etc.) Copolymers; glycidyl ether type epoxy resins represented by bisphenol type epoxy resin, novolak type epoxy resin, cresol novolak type epoxy resin, etc .; glycidyl ester type epoxy resins; aromatic glycidyl amine type epoxy resins; Examples include epoxy resins; heterocyclic epoxy resins; thiirane compounds in which oxygen atoms in oxirane rings of oxirane rings-containing compounds such as liquid rubber-modified epoxy resins are substituted with sulfur atoms.
[0037]
These C components are 8 to 60% by weight, preferably 10 to 50% by weight, based on the total amount of the A to C components. If the blending ratio of the component C is too small, the strength and heat resistance of the cured resin may be lowered, and if it is too much, the alkali developability may be lowered.
[0038]
[D component]
D component is a halomethyl-1,3,5-triazine compound represented by the following general formulas (L) to (N), and acts as a photopolymerization initiator.
Formula (L):
[0039]
[Chemical 8]

General formula (M):
[0040]
[Chemical 9]

Formula (N):
[0041]
[Chemical Formula 10]

[0042]
Examples of the alkyl group defined by the general formulas (L) to (M) include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, and a nonyl group. . Examples of the alkyl group of the alkoxy group, alkoxycarbonyl group or fluorinated alkyl group are the same as above. Examples of the halogen atom include Cl, Br, F, and the like.
Specific examples of the trihalomethyl-1,3,5-triazine compounds represented by these formulas are shown below together with CAS (American Chemical Society Chemical Abstract Service) registration numbers.
[0043]

[0044]
Among them, preferred halomethyl-1,3,5-triazine compounds are as follows.

[0045]
The blending ratio of component D in the composition of the present invention is usually 0.05 to 3% by weight, preferably 0.1 to 1.5% by weight, based on the total amount of components A to C. If this ratio is too small, the sensitivity of the resulting insulating layer may be significantly reduced due to the influence of the surrounding environment such as oxygen. On the other hand, if it is too large, the compatibility with other components will be inferior, and the coating surface In some cases, the absorption of light increases, causing problems such as inability to obtain a curing depth.
[0046]
[Other components or additives]
In the radiation-sensitive composition of the present invention, various rubber components and solvents, additives such as adhesion aids, fillers, colorants, viscosity modifiers, leveling agents, antifoaming agents, etc. may be added as necessary. it can.
[0047]
That is, a rubber component such as liquid rubber or crosslinked rubber particles can be added to the composition of the present invention in order to supplement the adhesiveness, strength, roughened surface formation and the like of the cured product. This rubber component needs to have high compatibility or affinity with each of the components A to D. When a rubber component having low compatibility or affinity is used, problems such as stickiness of the resulting composition and insufficient strength and roughened surface formability may occur.
[0048]
Examples of the liquid rubber or the crosslinked rubber particles include various known synthetic rubbers. Since high compatibility or affinity is obtained with respect to the component A, acrylic rubber (ACM), acrylonitrile-butadiene rubber ( NBR) and acrylonitrile acrylate butadiene rubber (NBA) are preferable, and those having at least one functional group selected from an epoxy group, a hydroxyl group, a carboxyl group and an amino group can be used as necessary. Practically, a synthetic rubber having an epoxy group or a carboxyl group is preferable, and a synthetic rubber having a carboxyl group is particularly preferable.
[0049]
The liquid rubber may be produced by any known method, and various methods such as emulsion polymerization, solution polymerization, bulk polymerization and suspension polymerization can be used for the production, and the polymerization method is also a batch type. Either batch type or continuous type may be used. The liquid rubber thus obtained contains an ionic component, but the liquid rubber preferably has a low ionic component content, whereby an insulating layer having high electrical insulation can be formed. When a diene monomer is contained in the monomer composition for obtaining a liquid rubber, the polymerization of this composition can be easily carried out by an emulsion polymerization method, particularly in JP-A-62-74908. If emulsion polymerization is carried out according to the indicated method, a liquid rubber with a small content of ionic components can be obtained.
[0050]
On the other hand, as for the crosslinked rubber particles, those having a particle size in the range of 10 nm to 1000 nm are preferably used.
[0051]
A solvent can be added to the composition of the present invention in order to improve the coating property and uniformity of the composition. Solvents include N-methylformamide, N, N-dimethylformamide, N-methylformanilide, N-methylacetamide, N, N-dimethylacetamide, N-methylpyrrolidone, dimethyl sulfoxide, benzyl ethyl ether, dihexyl ether, aceto Nylacetone, isophorone, caproic acid, caprylic acid, 1-octanol, 1-nonanol, benzyl alcohol, benzyl acetate, ethyl benzoate, ethyl lactate, diethyl oxalate, diethyl maleate, γ-butyrolactone, cyclohexanone, ethylene carbonate, carbonic acid Propylene, phenyl cellosolve acetate, methoxymethyl propionate, ethoxyethyl propionate, diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, Ethylene glycol dimethyl ether high boiling point solvent such as triethylene glycol methyl ethyl ether. The ratio of these solvents can be changed according to the use of the composition and the application method, and is not particularly limited as long as the composition can be made uniform, but it is usually used for the obtained liquid composition. 5 to 60% by weight, preferably 10 to 40% by weight.
[0052]
An adhesion assistant can be added to the composition of the present invention in order to improve the adhesion to the substrate to which the composition is applied. A functional silane coupling agent is effective as an adhesion aid. Here, the functional silane coupling agent means a silane coupling agent having a reactive substituent such as a carboxyl group, a methacryloyl group, an isocyanate group, an epoxy group, and examples thereof include trimethoxysilyl benzoic acid, γ -Methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, vinyltrimethoxysilane, γ-isocyanatopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxy Silane etc. can be mentioned, The compounding ratio is preferably 2 parts by weight or less per 100 parts by weight of the composition.
[0053]
In addition, additives such as a filler, a colorant, a viscosity modifier, a leveling agent, and an antifoaming agent can be added to the composition of the present invention. Examples of the filler include silica, alumina, talc, calcium carbonate, bentonite, zirconium silicate, and powdered glass. Colorants include alumina white, clay, barium carbonate, barium sulfate and other extender pigments; zinc white, lead white, yellow lead, red lead, ultramarine, bitumen, titanium oxide, zinc chromate, bengara, carbon black, etc. Pigments: Organic pigments such as brilliant carmine 6B, permanent red 6B, permanent red R, benzidine yellow, phthalocyanine blue, and phthalocyanine green; basic dyes such as magenta and rhodamine; direct dyes such as direct scarlet and direct orange; Examples include acid dyes such as yellow and others. Examples of the viscosity modifier include bentonite, silica gel, and aluminum powder. Examples of the leveling agent include various silicone compounds and polyalkylene oxide compounds. Examples of antifoaming agents include silicon compounds and fluorine compounds having a low surface tension. The ratio of these additives is within a range that does not impair the essential characteristics of the composition, and specifically, 50% by weight or less of the whole composition is appropriate.
[0054]
(Preparation of composition)
In order to prepare the composition of the present invention, when the filler and the pigment are not added, it is only necessary to mix and stir each component by a usual method. When the filler and the pigment are added, a dissolver, a homogenizer, What is necessary is just to disperse | distribute and mix using dispersers, such as a 3 roll mill. Moreover, it can also filter using a mesh, a membrane filter, etc. as needed.
[0055]
[Usage of composition]
The composition of the present invention is used, for example, for forming an insulating layer in the production of a multilayer wiring board. In order to produce a multilayer wiring board using the composition of the present invention, an insulating thin film made of the composition of the present invention is formed on the surface of the wiring board having a conductor wiring formed on the surface by the coating method. The thin film is exposed to radiation and developed with a developer to form, for example, a through-hole leading to the conductor wiring in the non-exposed area of the thin film, whereby the conductor wiring is exposed in the non-exposed area of the thin film. Then, a series of steps of forming a new conductor wiring that conducts the conductor wiring on the surface of the thin film may be performed once or repeated a plurality of times. That is, an insulating layer is formed using the composition of the present invention on the surface of the wiring board on which the nth conductor wiring is formed, and then the nth (where n is 1) The step of forming the (n + 1) -th conductor wiring that conducts with the above-described (integer) conductor wiring by plating or the like may be performed once or repeated a plurality of times.
[0056]
Below, the method of manufacturing a multilayer wiring board using the composition of this invention is demonstrated in more detail in order of a process.
(1) Thin film formation process
In this thin film forming step, for example, the composition of the present invention is applied to the surface of a wiring board formed with conductor wiring on the substrate surface so that the conductor wiring is covered, and then the coated surface is heated and dried. A thin film is formed by removing the solvent in the composition.
[0057]
Here, the material of the substrate on which the conductor wiring is formed is not particularly limited, and examples thereof include glass epoxy resin, paper phenol resin, ceramic, glass, and silicon wafer. Further, the coating method is not particularly limited, and a general photosensitive material coating method can be used. Specific examples include screen printing, roll coating, bar coating, dip coating, curtain coating, spin coating, and applicator methods. Alternatively, the composition of the present invention may be cast on a base film, formed into a film, and dried to produce a so-called dry film, which is bonded to a substrate with a laminator or the like to form a thin film. In this case, the base film is preferably a light-transmitting film. Examples of such a light-transmitting film include polyester films such as polyethylene terephthalate and polybutylene terephthalate; polyolefin films such as stretched polypropylene and polystyrene. Can be used. When the base film is a translucent film, the thin film can be photocured by exposing through the base film.
[0058]
The drying conditions after coating vary depending on the types and blending ratios of the components constituting the composition, the film thickness, and the like, but are usually about 70 to 130 ° C. for about 5 to 20 minutes. The thin film is dried using a normal apparatus such as an oven or a hot plate. Insufficient drying may cause stickiness on the surface of the thin film due to residual solvent, and may reduce the adhesion of the insulating layer to the substrate. On the other hand, excessive drying may cause heat fogging. The resolution may be degraded.
[0059]
The film thickness after drying of the thin film thus formed is usually 10 to 100 μm, preferably 30 to 70 μm. If the film thickness is too small, an insulating layer having sufficient insulation properties may not be formed. On the other hand, if the film thickness is too large, resolution may be lowered.
[0060]
(2) Exposure process
In this exposure processing step, the thin film formed on the wiring board by the thin film forming step is irradiated with radiation, for example, ultraviolet rays having a wavelength of 200 to 500 nm or visible light through a mask having a predetermined pattern, thereby forming a thin film. The light irradiation area (exposure area) is photocured. As the exposure processing apparatus, a fusion, a contact aligner, a stepper, a mirror projector, or the like can be used. Examples of the radiation light source include a low-pressure mercury lamp, a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, a metal halide lamp, an argon gas laser, an X-ray generator, and an electron beam generator. The amount of exposure for the thin film varies depending on the type and blending ratio of each component in the composition constituting the thin film, and the film thickness, but for example, when a high-pressure mercury lamp is used, 100 to 500 mJ / cm.²It is.
[0061]
(3) Heating step for curing acceleration
In this curing acceleration heating step, the thin film after the exposure treatment step is usually heated at a temperature of 70 to 130 ° C. for about 3 to 60 minutes, thereby causing a thermal reaction in addition to curing by a photoreaction in the exposure treatment step. Promotes thin film curing. This heating step is performed using a normal apparatus such as an oven or a hot plate. In addition, when this heating is excessive, the resolution may be lowered due to heat fogging.
[0062]
(4) Development process
In this development processing step, the composition in the non-exposed area is removed by dissolving it in a developer made of an alkaline aqueous solution, and only the cured composition in the exposed area is left to form a pattern.
[0063]
Here, as the developer, for example, sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, ammonia, ethylamine, n-propylamine, diethylamine, di-n-propylamine, triethylamine, methyldiethylamine , Dimethylethyl alcohol amine, triethyl alcohol amine, tetramethyl ammonium hydroxide, tetraethyl ammonium hydroxide, pyrrole, piperidine, 1,8-diazabicyclo [5.4.0] -7-undecene, 1,5-diazabicyclo [4. 3.0] An aqueous solution of an alkali compound such as 5-nonane can be used. In addition, an aqueous solution in which an appropriate amount of a water-soluble organic solvent such as methyl alcohol or ethyl alcohol or a surfactant is added to the above alkaline aqueous solution, or various organic solvents that dissolve the composition of the present invention is used as a developer. Can do. A preferred developer is an aqueous solution having a concentration of 0.1 to 3.0% by weight, particularly preferably 0.5 to 1.5% by weight, such as sodium hydroxide, potassium hydroxide, sodium carbonate, and tetramethylammonium hydroxide. is there.
[0064]
Examples of the developing method include a liquid piling method, a dipping method, a paddle method, and a spray developing method. After the development processing, for example, washing with running water is performed for 30 to 90 seconds, and drying is performed using an air gun or the like or in an oven.
A part of the thin film is removed by this development processing step, for example, a through hole is formed, and a part of the conductor wiring on the substrate surface is exposed. As a result, an insulating layer having a photo via hole is formed.
[0065]
(5) Thermosetting and / or post-exposure process
The composition of the present invention has both photo-curing properties and thermosetting properties, and after the development treatment, the heat-curing and / or post-exposure steps are performed to cure the insulating layer having photo via holes. Further promoted. Therefore, this thermal curing and / or post-exposure process is an unnecessary process when the insulating layer is in a sufficiently cured state. The thermosetting process is performed using a hot plate, oven, infrared oven, or the like under a temperature condition that does not cause thermal deterioration of the insulating layer, preferably at 150 to 180 ° C. for an appropriate time of about 30 minutes to 5 hours. Is called. Further, the post-exposure process uses, for example, a light source and an apparatus similar to those used in the exposure process, for example, 100 to 1,000 mJ / cm.²It is performed with the exposure amount.
[0066]
(6) Planarization process
This flattening process is an optional process for flattening an insulating layer formed on a non-flat substrate by polishing, for example. By flattening the insulating layer, conductor wiring is formed on the surface of the insulating layer. When formed, the accuracy of circuit processing can be improved. Here, as a grinding | polishing means, a baffle, a nylon brush, a belt sander etc. can be used, for example.
[0067]
(7) Through hole formation process
This through-hole formation process is a mechanical drilling using a numerically controlled drill machine or the like when a through-hole is required to achieve component insertion or connection with other wiring boards, that is, interlayer connection. This is a process for processing. In addition, in the manufacturing method of the multilayer printing plate using the composition of this invention, since an interlayer connection can be performed by a photo via hole, this through-hole formation process is an arbitrary process performed only when needed.
[0068]
(8) Roughening treatment process
This roughening treatment step is a step of roughening the surface of the insulating layer with a roughening treatment liquid in order to improve the adhesion of the conductor wiring formed on the surface of the insulating layer.
Roughening treatment liquids include alkaline treatment liquids such as aqueous potassium permanganate solution, aqueous solution of potassium permanganate and sodium hydroxide, mixed acids of chromic anhydride and sulfuric acid, and other strongly oxidizing ones. Used. Of these, an aqueous solution of potassium permanganate and sodium hydroxide is particularly preferred. In order to perform the roughening treatment, the insulating layer may be immersed in a treatment liquid maintained at a temperature of 50 to 80 ° C. for 5 to 30 minutes. In addition, after the surface roughening treatment, it is necessary to sufficiently wash the running surface with water after neutralizing the surface of the insulating layer with a weak acid aqueous solution such as oxalic acid as necessary.
[0069]
By this roughening treatment step, the surface of the insulating layer, the side wall surface of the photo via hole, and the side wall surface of the through hole become a rough surface state having an uneven shape of 0.01 to 10 μm. Strong adhesion is exerted on the copper plating layer constituting the.
[0070]
(9) Catalyst treatment process
This catalyst treatment step is a step of supporting a plating catalyst serving as a precipitation nucleus when performing electroless copper plating treatment in the next step on the surface of the insulating layer and the inner wall surface of the hole. Here, as the plating catalyst, for example, a metal colloid such as palladium can be used. The catalyst loading treatment is achieved by immersing the insulating layer in various known treatment liquids in which such metal colloids are dispersed in a medium. The composition of the present invention can contain a plating catalyst, and in this case, this step can be omitted.
[0071]
(10) New conductor wiring formation process
For example, this new conductor wiring forming process is performed by performing electroless copper plating treatment, so that electrical connection with the conductor wiring (first conductor wiring) already formed on the substrate surface through the photo via hole and the through hole is performed. This is a step of forming a new conductor wiring (second conductor wiring) on the surface of the insulating layer while realizing a general connection. As a method for forming a new conductor wiring, for example, the following methods {circle around (1)} to {circle around (3)} can be mentioned.
[0072]
Method (1):
Copper having a desired thickness is formed by performing an electroless copper plating process on the entire surface of the insulating layer supporting the catalyst to form a copper plating layer, and using the copper plating layer as an electrode, if necessary. A metal layer is formed, a resist pattern is formed on the copper metal layer, and then the copper metal layer is etched to form a conductor pattern. Here, in addition to the region where the second conductor wiring is formed, the resist pattern includes an interlayer connection photo via hole in which an interlayer connection conductor between the first conductor wiring and the second conductor wiring is formed. It is also formed in the position, i.e. the area where the conductor lands are to be formed. The diameter of the conductor land is preferably larger than the diameter of the photo via hole in consideration of misalignment error. The resist pattern is usually formed by photolithography using a photoresist. Etching of the copper metal layer is performed with an ammonium persulfate aqueous solution or an ammonia complex etching solution. After etching the copper metal layer, the resist pattern is peeled and removed by a predetermined method. The photoresist is not particularly limited as long as it has necessary resolution and resistance to an etching solution and can be removed later. In this way, the second conductor wiring that is electrically connected to the first conductor wiring on the surface of the substrate is formed on the insulating layer.
[0073]
Method (2):
An insulating layer is formed by forming a resist pattern in a region other than a region where a new conductor wiring is to be formed on the surface of the insulating layer on which the catalyst is supported, and then performing an electroless copper plating treatment and, if necessary, an electrolytic copper plating treatment. A new conductor wiring is formed on the surface, a copper plating layer is formed on the inner wall surface of the photo via hole, and then the resist pattern is peeled and removed. Also in this method, it is preferable to make the width of the conductor wiring larger than the diameter of the photo via hole.
[0074]
Method (3):
A coating film is formed by applying a photosensitive resin composition not containing a plating catalyst to the entire surface of the insulating layer on which the catalyst is supported. The coating film is exposed through a pattern mask, and then developed. In addition, a photo via hole is formed, and a portion of the coating film that becomes the second conductor wiring continuous with the photo via hole is removed, and only electroless copper plating is performed thereon. Also in this method, it is preferable to make the width of the conductor wiring larger than the diameter of the photo via hole. Moreover, it is preferable that the thickness of the film is the same as or slightly larger than the thickness of the copper metal layer formed by copper plating.
[0075]
According to this method, the second conductor wiring to be formed is formed in the removed portion of the film, and the insulating film made of the remaining film remains on the original insulating layer, and the remaining film and the copper metal Since the layer thicknesses are usually approximate, an outer surface with excellent flatness can be obtained.
In addition, as a photosensitive resin composition for forming the above film, the composition of this invention can be used.
[0076]
Further multilayering can be achieved by repeating the steps (1) to (10). In this case, the method (1) to (3) can be combined to form a multi-layer when the new conductor wiring forming step (10) is performed.
[0077]
In addition, after forming a conductor wiring on the surface of the insulating layer that is the uppermost layer of the multilayer wiring board, it is preferable to perform post-baking from the viewpoint of improving the adhesion between the insulating layer and the conductor wiring. Since the insulating layer other than the uppermost layer and the conductor wiring related to this insulating layer are heated in the subsequent heating step in forming the insulating layer, there is no need to perform post-baking as a single step.
[0078]
【Example】
EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited to these examples. Unless otherwise specified, “part” indicates “part by weight”, and “%” indicates “% by weight”.
[Component A] The following four types were prepared.
[0079]
A1: Cresol novolak resin [m-cresol: p-cresol = 6: 4 (molar ratio), weight average molecular weight Mw = 11,000]
A2: phenol novolac resin [weight average molecular weight Mw = 6000]
A3: Poly (p-vinylphenol) [manufactured by Maruzen Kasei Co., Ltd., weight average molecular weight Mw = 3,000]
A4: Poly (brominated p-vinylphenol) ["Maruka Linker MB" manufactured by Maruzen Kasei Co., Ltd., weight average molecular weight Mw = 4,000]
[Component B] The following three amino resins were prepared.
[0080]
B1: Hexamethoxymethylated melamine [Mitsui Cytec "Cymel 300"]
B2: Tetramethoxymethylated glycoluril [Mitsui Cytec "Cymel 1170"]
B3: Benzoguanamine resin ["BX-4000" manufactured by Sanwa Chemical Co., Ltd.]
[C component]
C1: Bisphenol A type epoxy resin (manufactured by Yuka Shell Epoxy Co., Epicoat 828)
C2: Novolac type epoxy resin (manufactured by Nippon Kayaku Co., Ltd., EOCN-100)
C3: 2,2 ′-[(1-methylethylidene) bis (4,1-phenyleneoxymethylene)] bisthiirane
C4: 1,4-bis [(3-ethyl-3-oxetanylmethoxy) methyl] benzene
[Component D] The following three photopolymerization initiators were prepared.
[0081]
D1: 2,4-trichloromethyl- (4'-methoxyphenyl) -6-triazine
D2: 2,4-trichloromethyl- (4'-methoxystyryl) -6-triazine
D3: Diphenyliodonium-9,10-dimethoxyanthracenesulfonate
D4: Triphenylsulfonium hexafluorophosphate
[0082]
〔Additive〕
E: butadiene-acrylonitrile-methacrylic acid copolymer [butadiene: acrylonitrile: methacrylic acid = 60: 35: 5 (molar ratio), number average molecular weight Mn = 6,000, glass transition point Tg = −39 ° C.]
[Solvent] The following two organic solvents were prepared.
[0083]
MMP: methyl 3-methoxypropionate
PGMEA: Propylene glycol monomethyl ether acetate <Examples 1-7, Comparative Examples 1-4 (preparation of composition)>
In accordance with the formulation shown in Table 1 below, the above components A to D, and if necessary, additives and solvents are blended, and each of the resulting blends is mixed and stirred with a Henschel mixer, thereby giving radiation sensitivity. A functional resin composition was prepared.
[0084]
[Table 1]

[0085]
<Performance evaluation of composition and insulating layer, and production of multilayer wiring board>
(1) Production and evaluation of photosensitive characteristic evaluation test substrate
A plate-like body made of a glass epoxy resin having a copper metal layer formed on one side was used as a test piece, and each of the compositions prepared in Examples 1 to 7 and Comparative Examples 1 to 4 was spin-coated on the surface. And dried in a hot air oven at 90 ° C. for 10 minutes to form a thin film having a thickness of about 50 μm after drying.
[0086]
For each of the test pieces thus obtained, the thin film was exposed through a test glass mask on which a perforation pattern having a diameter of 25 μm, 50 μm, 75 μm, 100 μm, 150 μm, or 200 μm was formed. The exposure process uses a contact aligner ("ML-3 type" manufactured by Mikasa Electric Co., Ltd.), and 1,000 mJ / cm at the contact (contact exposure).²The exposure amount was.
[0087]
The exposed test piece was heated at 120 ° C. for 5 minutes, and then developed by immersing it in a 0.75% aqueous solution of tetramethylammonium hydroxide for 180 to 300 seconds for rocking. An insulating layer having a through-hole reaching to 1, that is, a photo via hole was formed. Thereafter, each of the test pieces on which the insulating layer was formed was washed with water and dried. At this time, the developability was evaluated assuming that a through-hole having a diameter of 75 μm was completely formed was good and the other one was defective.
[0088]
Next, each of the test pieces on which the insulating layer is formed is cured by heating in a hot air oven at a temperature of 150 ° C. for 60 minutes, and then the heat-cured test piece is maintained at a temperature of 65 ° C. The surface of the insulating layer is roughened by immersing it in a potassium manganate-sodium hydroxide aqueous solution (potassium permanganate concentration 3%, sodium hydroxide concentration 2%) for 10 minutes. The surface of the piece was neutralized by immersing it in an aqueous oxalic acid solution having a concentration of 5% at room temperature for 5 minutes, and further washed thoroughly with water.
[0089]
For each of the test pieces, the surface state of the insulating layer was observed with a scanning electron microscope to evaluate the state of the roughening treatment. The evaluation method was defined as “good” when the surface of the insulating layer was sufficiently roughened to form fine irregularities, and “bad” otherwise.
[0090]
In addition, each test piece is immersed in a palladium chloride catalyst solution at room temperature for 6 minutes, whereby the plating catalyst is supported on the surface of the roughened insulating layer and the inner surface of the through hole, and further, the catalyst activation solution. The plating catalyst was activated by immersing in room temperature for 8 minutes. Thereafter, each of the test pieces was washed with water, and then subjected to electroless copper plating at room temperature for 20 minutes. In this treatment, the catalyst solution, catalyst activation solution, and electroless copper plating solution used were those of “OPC Process M Series” (Okuno Pharmaceutical Co., Ltd.). Next, using an electrolytic copper plating solution made of a copper sulfate-sulfuric acid aqueous solution (copper sulfate concentration 210 g / L, sulfuric acid concentration 52 g / L, pH = 1.0), electrolytic copper plating treatment at a current density of 3.0 mA / dm Then, a copper metal layer having a total thickness of about 20 μm was formed over the entire surface of the insulating layer, and then this test piece was heat-treated at 150 ° C. for 1 hour.
[0091]
The peel strength (JIS C 6481) of the copper metal layer was measured by forming incisions at intervals of 1 cm on the surfaces of these test pieces and peeling them from the end surfaces with a peel tester. This peel strength is the mode value after peeling off by 10 cm, and the one showing a strength of 800 g / cm or more was regarded as acceptable.
[0092]
(2) Evaluation of electric corrosion resistance
An insulating layer having a thickness of 50 μm is formed on a comb-shaped electrode substrate (made of BT (bismaleimide triazine) resin, 10 × 10 cm square) for evaluation of electrolytic corrosion with a wiring pitch of 100 μm. (1) According to a method for preparing and evaluating a photosensitive property evaluation test substrate Thus, an electrolytic corrosion evaluation substrate was prepared. This electric corrosion evaluation substrate was placed in a constant temperature and humidity chamber of 85 ° C. × 85% RH, and the insulation resistance value was recorded while a direct current of 100 V was continuously applied to the substrate. Insulation resistance is 10⁸The time until the ohm was cut was obtained and defined as the electric corrosion resistance time (hr).
The results are shown in Table 2. As is apparent from this table, Examples 1 to 7 all had good performance such as developability, rough surface state, peel strength and the like, and had a long electric corrosion resistance and excellent electric corrosion resistance. On the other hand, Comparative Examples 1 to 4 had good performance such as developability, rough surface state, peel strength, etc., but were inferior in electric corrosion resistance. That is, it can be seen that the composition of the present invention has improved electrolytic corrosion resistance without degrading various performances such as developability, rough surface state, and peel strength.
[0093]
[Table 2]

[0094]
【The invention's effect】
The radiation-sensitive resin composition according to the present invention contains, as an essential component, a compound having a plurality of crosslinkable groups such as an epoxy group, an oxetanyl group, a tyraniyl group, or a vinyl ether group in one molecule together with an alkali-soluble phenol resin and an amino resin. In particular, in the production of a multilayer wiring board, for example, it has excellent resolution capable of forming a small-diameter photo via hole with high accuracy and can be developed with an aqueous alkaline solution. An insulating layer having excellent adhesion of the conductor wiring and having good solvent resistance, water resistance and heat resistance can be formed after curing. Therefore, by using the composition of the present invention, a multilayer wiring board having high electrical insulation reliability can be efficiently produced.

Claims (1)

The radiation sensitive resin composition for insulating layer formation characterized by containing the following A component-D component.
[Component A] phenol resin [component B] amino resin [Component C] The compound having a plurality of crosslinkable groups in a molecule [component D] halomethyl-1,3,5-triazine compound