JP4359993B2 - Method for processing photosensitive resin composition and semiconductor device using the method - Google Patents

Description

【００１３】
式（１）のＸには、例えば、下記のものが挙げられるが、特にこれらに限定されるものではない。
【化８】

【００１４】
また式（１）のＹには、例えば下記のものが挙げられるが、特にこれらに限定されるものではない。
【化９】

【００１５】
また式（１）のＥには例えば下記のものが挙げられるが、特にこれらに限定されるものではない。
【化１０】

【００１６】
更に、式（１）のＺには、例えば下記のものが挙げられるが、特にこれらに限定されるものではない。
【化１１】

【００１７】
なお、これらＸ，Ｙ，Ｅ，Ｚの使用にあたっては、それぞれ１種類であっても２種類以上の混合物であっても構わない。
【００１８】
本発明のポジ型樹脂組成物は、一般式（１）で示されるポリベンゾオキサゾール前駆体を主体とし、ポジ型感光剤を配合することを基本としている。
本発明で使用するポジ型感光剤は、１，２―ベンゾキノンジアジドあるいは１，２−ナフトキノンジアジト構造を有するジアゾキノン化合物である。これらは、米国特許明細書第2,772,972号、第2,797,213号、第3,669,658号に開示された公知の物質である。
【００１９】
これらのキノンジアジド化合物をノボラック樹脂に配合したポジレジストは、半導体チップ上の回路作製のために、現在盛んに使用されている。すなわち、キノンジアジド化合物は溶解阻止能を有しているため、ノボラック樹脂の溶解性を低下させ、高残膜のレリーフパターンを与えることが出来る。
ところが、特公平1-46862号公報に開示されているように、ノボラック樹脂に効果のあるキノンジアジド化合物でも、ポリベンゾオキサゾール前駆体に対しては効果が無く、溶解阻止能が低いものがある。溶解阻止能が低いと残膜率が低くなり、良好なパターン形状を得ることが出来ない。本発明で使用するキノンジアジド化合物としては下記のものが挙げられるが、特にこれらに限定されるものではない。
【００２０】
【化１２】

【００２１】
本発明で使用するポジ型感光性樹脂組成物には、必要により感光特性を高めるためのジヒドロピリジン誘導体を加えることが出来る。ジヒドロピリジン誘導体としては、例えば２，６−ジメチル−３，５−ジアセチル−４−（２‘−ニトロフェニル）−１，４−ジヒドロピリジン、４−（２’−ニトロフェニル）−２，６−ジメチル−３，５−ジカルボエトキシ−１，４−ジヒドロピリジン、４−（２‘，４’−ジヒドロフェニル）−２，６−ジメチル−３，５−ジカルボメトキシ−１，４−ジヒドロピリジン等を挙げることが出来る。
【００２２】
本発明で使用するポジ型感光性樹脂組成物には、感度特性を高め、かつ露光部の溶解性を向上させるために溶解促進剤を配合することが出来る。溶解促進剤としては、例えば下記のようなフェノール化合物が挙げられるが、特にこれらに限定されるものではない。
【００２３】
【化１３】

【００２４】
【化１４】

【００２５】
本発明で使用するポジ型感光性樹脂組成物には、一般式（４）、（５）、（６）で示される有機ケイ素化合物を、ポジ型感光性樹脂硬化膜とシリコンウエハー及び半導体封止用エポキシ樹脂硬化物との接着性を向上させるために配合する。有機ケイ素化合物は１種または２種類以上混合して用いてもよい。また、使用量は、少なすぎると接着性向上効果が得られず、多すぎるとポジ型感光性樹脂硬化膜の機械強度が低下して応力緩和効果が薄れるので好ましくない。
【００２６】
【化１５】

【化１６】

【化１７】

【００２７】
一般式（４）、（５）で示される有機ケイ素化合物は、酸（二）無水物とアミノ基を備えたシランカップリング剤とを有機溶媒中、２０〜１００℃で３０分〜１０時間反応させることにより得られる。
【００２８】
酸無水物としては、無水マレイン酸、無水コハク酸、メチルテトラヒドロ無水フタル酸、メチルヘキサヒドロ無水フタル酸、無水メチルハイミック酸、ヘキサヒドロ無水フタル酸、テトラヒドロフタル酸、無水フタル酸などが挙げられるが、特にこれらに限定されるものではない。
【００２９】
また酸二無水物としては、ピロメリット酸二無水物、ベンゼン−１，２，３，４−テトラカルボン酸二無水物、３，３‘，４，４’−ベンゾフェノンテトラカルボン酸二無水物、２，２‘，３，３’−ベンゾフェノンテトラカルボン酸二無水物、２，３，３‘，４’−ベンゾフェノンテトラカルボン酸二無水物、ナフタレン−，２，３，６，７−テトラカルボン酸二無水物、ナフタレン−１，２，４，５−テトラカルボン酸二無水物、ナフタレン−１，４，５，８−テトラカルボン酸二無水物、ナフタレン−１，２，６，７−テトラカルボン酸二無水物、４，８−ジメチル−１，２，３，５，６，７−ヘキサヒドロナフタレン−１，２，５，６−テトラカルボン酸二無水物、４，８−ジメチル−１，２，３，５，６，７−ヘキサヒドロナフタレン−２，３，６，７−テトラカルボン酸二無水物、２，６−ジクロロナフタレン−１，４，５，８−テトラカルボン酸二無水物、２，７−ジクロロナフタレン−１，４，５，８−テトラカルボン酸二無水物、２，３，６，７−テトラクロロナフタレン−１，４，５，８−テトラカルボン酸二無水物、３，３‘，４，４’−ジフェニルテトラカルボン酸二無水物、２，２‘，３，３’−ジフェニルテトラカルボン酸二無水物、２，３，３‘，４’−ジフェニルテトラカルボン酸二無水物、３，３“，４，４”−ｐ−テルフェニルテトラカルボン酸二無水物、２，２“，３，３”−ｐ−テルフェニルテトラカルボン酸二無水物、２，３，３“，４”−ｐ−テルフェニルテトラカルボン酸二無水物、２，２−ビス（２，３−ジカルボキシフェニル）−プロパン二無水物、２，２−ビス（３、４―ジカルボキシフェニル）−プロパン二無水物、ビス（２，３−ジカルボキシフェニル）エーテル二無水物、ビス（３，４−ジカルボキシフェニル）エーテル二無水物、ビス（２，３−ジカルボキシフェニル）メタン二無水物、ビス（３，４−ジカルボキシフェニル）メタン二無水物、ビス（２，３−ジカルボキシフェニル）スルホン二無水物、１，１−ビス（２，３−ジカルボキシフェニル）エタン二無水物、１，１−ビス（３，４−ジカルボキシフェニル）エタン二無水物、ペリレン−２，３，８，９−テトラカルボン酸二無水物、ペリレン−３，４，９，１０−テトラカルボン酸二無水物、ペリレン−４，５，１０，１１−テトラカルボン酸二無水物、ペリレン−５，６，１１，１２−テトラカルボン酸二無水物、フェナンスレン−１，２，７，８−テトラカルボン酸二無水物、フェナンスレン−１，２，６，７−テトラカルボン酸二無水物、フェナンスレン−１，２，９，１０−テトラカルボン酸二無水物、ピラジン−２，３，５，６−テトラカルボン酸二無水物、ピロリジン−２，３，４，５−テトラカルボン酸二無水物、チオフェン−２，３，４，５−テトラカルボン酸二無水物、４，４‘−ヘキサフルオロイソプロピリデンジフタル酸二無水物等が挙げられるが、特にこれらに限定されるものではない。
【００３０】
アミノ基を有するシランカップリング剤としては、γ−アミノプロピルトリメトキシシラン、γ−アミノプロピルトリエトキシシラン、γ−アミノプロピルメチルジエトキシシラン、γ−アミノプロピルメチルジメトキシシラン、γ−アミノプロピルエチルジメトキシシラン、γ−アミノプロピルエチルジエトキシシラン、γ−アミノプロピルジメチルメトキシシラン、γ−アミノプロピルジメチルエトキシシラン、γ−アミノプロピルエチルジエトキシシラン、γ−アミノプロピルエチルメトキシシラン、γ−アミノプロピルジエチルエトキシシラン、Ｎ−（β−アミノエチル）−γ−アミノプロピルトリメトキシシラン、Ｎ−（β−アミノエチル）−γ−アミノプロピルメチルジメトキシシラン、４−アミノブチルジメチルメトキシシラン等が挙げられるが、特にこれらに限定されない。
【００３１】
一般式（６）で示される有機ケイ素化合物は、エポキシ基を有するシランカップリング剤とテトラカルボン酸二無水物と２０〜１００℃で３０分〜１０時間反応させることによって得られる。
酸二無水物としては、一般式（４）の有機ケイ素化合物の場合と同様のものが挙げられるが、特にこれに限定されない。また、シランカップリング剤としては、γ−グリシドキシプロピルトリメトキシシラン、γ−グリシドキシプロピルトリエトシキシラン、γ−グリシドキシプロピルメチルジメトキシシラン、γ−グリシドキシプロピルメチルジエトキシシラン、γ−グリシドキシプロピルエチルジエトキシシラン、γ−グリシドキシプロピルジメチルメトキシシラン、γ−グリシドキシプロピルジメチルエトキシシラン、γ−グリシドキシプロピルジエチルメトキシシラン、γ−グリシドキシプロピルジエチルエトキシシラン等が挙げられるが、特にこれに限定されない。
【００３２】
上記の一般式（４）、（５）、（６）で表される有機ケイ素化合物は、反応することによって得られ、かつこれを配合したポジ型感光性樹脂組成物に優れた特性を付与しているが、反応せずに各々の原料をそのまま配合することによっても優れた特性を発現させることができる。
【００３３】
本発明で使用するポジ型感光性樹脂組成物には、必要によりレベリング剤、シランカップリング剤等の添加剤を添加することができる。またワニス状にするために、各種の溶剤が使用される。溶剤としては、Ｎ−メチル−２−ピロリドン、γ−ブチロラクトン、Ｎ，Ｎ−ジメチルアセトアミド、ジメチルスルホキシド、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ジエチルエーテル、ジエチレングリコールジブチルエーテル、プロピレエングリコールモノメチルエーテル、ジプロピレングリコールモノメチルエーテル、ジプロピレングリコールモノメチルエーテルアセテート、乳酸メチル、乳酸エチル、乳酸ブチル、メチル−１，３−ジブチレングリコールアセテート、１，３−ジブチレングリコール−３−モノメチルエーテル、プルビン酸メチル、プルビン酸エチル、メチル−３−メトキシプロピオネート等が挙げられるが、これに限定されない。また、溶剤は単独でも混合して使用してもよい。
【００３４】
本発明のポジ型感光性樹脂組成物の使用方法は、まず該組成物を適当な支持体、例えば、シリコンウェハー、セラミック基板、アルミ基板等に塗布する。塗布方法としては、スピンナーを用いた回転塗布、スプレーコーターを用いた噴霧塗布、浸漬、印刷、ロールコーティング等がある。次に、６０〜１３０℃でプリベークして塗膜を乾燥後、所望のパターン形状に化学線を照射する。化学線としては、Ｘ線、電子線、紫外線、可視光線等が使用できるが、２００〜５００ｎｍの波長のものが好ましい。次に照射部を現像液で溶解除去することによりレリーフパターンを得る。現像液としては、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、アンモニア水等の無機アルカリ類、エチルアミン、ｎ−プロピルアミン等の第１アミン類、ジエチルアミン、ジ−ｎ−プロピルアミン等の第２アミン類、トリエチルアミン、メチルジエチルアミン等の第３アミン類、ジメチルエタノールアミン、トリエタノールアミン等のアルコールアミン類、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等の第４級アンモニウム塩等のアルカリ類の水溶液、及びこれにメタノール、エタノールのごときアルコール類等の水溶性有機溶媒や界面活性剤を適当量添加した水溶液を好適に使用することができる。現像方法としては、スプレー、パドル、浸漬、超音波等の方式が可能である。次に、現像によって形成したレリーフパターンをリンスする。リンス液としては、蒸留水等を使用する。その後、プレエッチベークを行う。プレエッチベークの温度は、プリベーク以上の温度で、好ましくは１２０℃〜２５０℃で乾燥を行う。乾燥機は、オーブン炉、ファーネス炉、ホットプレート等、高温熱処理可能ならば特に限定しない。次に、ポジ型樹脂をマスクにリアクティブイオンエッチング（ＲＩＥ）等によりガラス無機保護膜等をエッチングし、次に加熱処理を行い、オキサゾール環を形成し、耐熱性に富む最終パターンを得る。加熱温度は、オキサゾール環を形成するという意味においては、２５０℃以上、より好ましくは３００℃〜４００℃にすることが好ましいが、２５０℃以下でも長時間のベークを行えば十分な性能が得られるが生産時間が長くなる。酸素濃度は、窒素パージ下で５％以下、前記したように、より好ましくは、１％以下であることが好ましい。乾燥機の種類によれば1000ppm以下の低酸素濃度にすることが好ましく、この場合酸化がされにくいため、より高温で硬化させることが可能となり、感光性樹脂の耐熱性を向上させることが可能となる。
【００３５】
本発明による感光性樹脂組成物は、半導体用途のみならず、多層回路の層間絶縁やフレキシブル銅張板のカバーコート、ソルダーレジスト膜や液晶配向膜等としても有用である。
本発明の感光性樹脂組成物の加工方法を用いて製作された半導体装置は高信頼性の半導体装置である。本加工方法を除く半導体装置の製造方法は従来の公知の方法を用いることが出来る。
【００３６】
【実施例】
以下、実施例により本発明を具体的に説明する。
《実施例１》
＊ポリアミドの合成
ジフェニルエーテル−４，４’−ジカルボン酸１モルと１−ヒドロキシ−１，２，３−ベンゾトリアゾール２モルとを反応させて得られたジカルボン酸誘導体４４３．２ｇ（０．９モル）とヘキサフルオロ−２，２−ビス（３−アミノ−４−ヒドロキシフェニル）プロパン３６６．３ｇ（１．０モル）とを温度計、攪拌機、原料投入口、乾燥窒素ガス導入管を備えた４つ口のセパラブルフラスコに入れ、Ｎ−メチル−２−ピロリドン３０００ｇを加えて溶解させた。その後オイルバスを用いて７５℃にて１２時間反応させた。
次にＮ−メチル−２−ピロリドン５００ｇに溶解させた５−ノルボルネン−２，３−ジカルボン酸無水物３２．８ｇ（０．２モル）を加え、更に１２時間攪拌して反応を終了した。反応混合物をろ過した後、反応混合物を水／メタノール＝３／１の溶液に投入、沈殿物を濾集し水で充分洗浄した後、真空下で乾燥し、目的のポリアミド（Ａ−１）を得た。
【００３７】
＊ポジ型感光性樹脂組成物の作製
合成したポリアミド（Ａ−1）１００ｇ、下記式の構造を有するジアゾキノン（Ｂ１）２５ｇ、下記式の構造を有するフェノール化合物（Ｐ１）１０ｇ、（Ｐ２）５ｇ、γーアミノプロピルトリエトキシシランと無水マレイン酸を反応させて得られた有機ケイ素酸化合物を２ｇ、γーアミノプロピルトリエトキシシランと３、３’、４、４’−ベンゾフェノンテトラカルボン酸二無水物を反応させて得られた有機ケイ素化合物を１ｇをＮ−メチル−２−ピロリドン２５０ｇに溶解した後、０．２μｍのテフロンフィルターで濾過し感光性樹脂組成物を得た。
【００３８】
【化１８】

【００３９】
【化１９】

【００４０】
＊パターンの作成
このポジ型感光性樹脂組成物をシリコンウェハー上にスピンコーターを用いて塗布した後、ホットプレートにて１２０℃で４分乾燥し、膜厚約５μｍの塗膜を得た。この塗膜にｇ線ステッパー露光機ＮＳＲ−１５０５Ｇ３Ａ（ニコン(株)製）によりレチクルを通して５０ｍＪ／ｃｍ²から１０ｍＪ／ｃｍ²ずつ増やして５４０ｍＪ／ｃｍ²まで露光を行った。
次に１．４０％のテトラメチルアンモニウムヒドロキシド水溶液に６０秒浸漬することによって露光部を溶解除去した後、純水で３０秒間リンスした。その結果、露光量２３０ｍＪ／ｃｍ²で照射した部分よりパターンが成形されていることが確認できた。（感度は２３０ｍＪ／ｃｍ²）。この時の残膜率（現像後の膜厚／現像前の膜厚×１００）は９３．１％と非常に高い値を示した（この状態の樹脂をＥＸ１とする）。ここで作成した現像後ウエハを１３０℃で９０分間硬化を行った後に、エッチング装置ＯＰＭ−ＥＭ１０００（東京応化工業（株）製）を用いて、１０００Ｗで２分間の酸素プラズマ処理を行った。
処理後の膜厚は、約３μmであった。樹脂表面には、特に異常はなく良好な状態であった。
【００４１】
また、上記同様の塗布によりプリベーク後膜厚１５μmの塗膜を得、その後、露光をせずに上記同様に現像を行ったもの（この状態の樹脂をＮＥＸ１とする）を１３０℃で９０分間硬化を行った後に、エッチング装置ＯＰＭ−ＥＭ１０００（東京応化工業（株）製）を用いて、１０００Ｗで２分間の酸素プラズマ処理を行った。このウエハを３２０℃で３０分間硬化を行い、ウエハから剥離後硬化膜を得た。
テンシロンを用いて、この硬化膜の引っ張り特性を評価した。引っ張り強度は、１２．５kg/mm²、引っ張り弾性率は２５６kg/ mm²、引っ張り伸び率は４５％と高い値を示し、プラズマによるダメージによる強度低下は見られなかった。
【００４２】
《実施例２》
実施例１で作成した現像後ウエハ（ＥＸ１とＮＥＸ１）を２００℃で６０分間硬化を行った後に、エッチング装置ＯＰＭ−ＥＭ１０００（東京応化工業（株）製）を用いて、１０００Ｗで２分間の酸素プラズマ処理を行った。
ＥＸ１の膜厚は、約３．２μmで樹脂表面は特に異常なく良好であった。ＮＥＸ１は実施例１と同様に硬化を行った後に引っ張り特性を評価した。引っ張り強度は、１２．３kg/ mm²、引っ張り弾性率は２６３kg/ mm²、引っ張り伸び率は５２％と高い値を示し、プラズマによるダメージによる強度低下は見られなかった。
【００４３】
《実施例３》
実施例１で作成した現像後ウエハ（ＥＸ１とＮＥＸ１）を２２５℃で６０分間硬化を行った後に、エッチング装置ＯＰＭ−ＥＭ１０００（東京応化工業（株）製）を用いて、１０００Ｗで２分間の酸素プラズマ処理を行った。
ＥＸ１の膜厚は、約３．２μmで樹脂表面は特に異常なく良好であった。ＮＥＸ１は実施例１と同様に硬化を行った後に引っ張り特性を評価した。引っ張り強度は、１２．５kg/ mm²、引っ張り弾性率は２５９kg/ mm²、引っ張り伸び率は４９％と高い値を示し、プラズマによるダメージによる強度低下は見られなかった。
【００４４】
《実施例４》
実施例１で作成した現像後ウエハ（ＥＸ１とＮＥＸ１）を２５０℃で３０分間硬化を行った後に、エッチング装置ＯＰＭ−ＥＭ１０００（東京応化工業（株）製）を用いて、１０００Ｗで２分間の酸素プラズマ処理を行った。
ＥＸ１の膜厚は、約３．３μmで樹脂表面は特に異常なく良好であった。ＮＥＸ１は実施例１と同様に硬化を行った後に引っ張り特性を評価した。引っ張り強度は、１２．７kg/ mm²、引っ張り弾性率は２４８kg/ mm²、引っ張り伸び率は４５％と高い値を示し、プラズマによるダメージによる強度低下は見られなかった。
【００４５】
《実施例５》
実施例１におけるポリアミドの合成において、ジフェニルエーテル−４，４’−ジカルボン酸１モルと１−ヒドロキシ−１，２，３−ベンゾトリアゾール２モルとを反応させて得られたジカルボン酸誘導体の代わりに、ジフェニルスルホン−４，４’−ジカルボン酸１モルと１−ヒドロキシ−１，２，３−ベンゾトリアゾール２モルとを反応させて得られたジカルボン酸誘導体を用いてポリアミド（Ａ−2）を合成し、その他は実施例１と同様の評価を行った。
【００４６】
《実施例６》
実施例１におけるポリアミドの合成においてヘキサフルオロ−２，２−ビス（３−アミノ−４−ヒドロキシフェニル）プロパンの替わりに３，３’−ジアミノ−４，４’−ジヒドロキシジフェニルスルホンを用いて、ポリアミド（Ａ−３）を合成し、その他は実施例１と同様の評価を行った。
【００４７】
《比較例１》
実施例１で作成した現像後ウエハ（ＥＸ１とＮＥＸ１）を３５０℃で６０分間硬化を行った後に、エッチング装置ＯＰＭ−ＥＭ１０００（東京応化工業（株）製）を用いて、１０００Ｗで２分間の酸素プラズマ処理を行った。
ＥＸ１の膜厚は、約３．７μmで樹脂表面は２〜１０μm程度の穴が多数存在していた。ＮＥＸ１は実施例１と同様に硬化を行った後に引っ張り特性を評価した。引っ張り強度は、１０．９kg/ mm²、引っ張り弾性率は２３２kg/ mm²、引っ張り伸び率は１８％と低い値を示し、プラズマによるダメージによる強度低下が見られた。
【００４８】
《比較例２》
実施例５で作成した現像後ウエハ（ＥＸ１とＮＥＸ１）を３８０℃で３０分間硬化を行った後に、エッチング装置ＯＰＭ−ＥＭ１０００（東京応化工業（株）製）を用いて、１０００Ｗで２分間の酸素プラズマ処理を行った。
ＥＸ１の膜厚は、約3.8μmで樹脂表面は２〜１０μm程度の穴が多数存在していた。ＮＥＸ１は実施例１と同様に硬化を行った後に引っ張り特性を評価した。引っ張り強度は、１０．４kg/ mm²、引っ張り弾性率は２２１kg/ mm²、引っ張り伸び率は１５％と低い値を示し、プラズマによるダメージによる強度低下が見られた。
【００４９】
《比較例３》
実施例１で作成した現像後ウエハ（ＥＸ１とＮＥＸ１）を３２０℃で３０分間硬化を行った後に、エッチング装置ＯＰＭ−ＥＭ１０００（東京応化工業（株）製）を用いて、１０００Ｗで２分間の酸素プラズマ処理を行った。
ＥＸ１の膜厚は、約３．５μmで樹脂表面は１〜３μm程度の穴が少数存在していた。ＮＥＸ１は実施例１と同様に硬化を行った後に引っ張り特性を評価した。引っ張り強度は、１１．３kg/ mm²、引っ張り弾性率は２４２kg/ mm²、引っ張り伸び率は３２％とを示し、プラズマによるダメージによる強度低下が若干見られた。
【００５０】
実施例１〜６、比較例１〜３の評価結果を表１に示す。
【表１】

【００５１】
【発明の効果】
本発明によって、半導体上の感光性樹脂組成物のエッチング時における樹脂のダメージを低減することができる。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for processing a photosensitive resin composition capable of reducing damage during etching.
[0002]
[Prior art]
In recent years, in the semiconductor industry, photosensitive resin compositions such as photoresists and photosensitive polyimides are frequently used for insulating films and protective films in packages that require the creation or processing of ultrafine circuits such as ICs and LSIs. The characteristic of the photosensitive resin is that a resin pattern with excellent accuracy can be obtained with a relatively simple apparatus. In particular, a positive photoresist based on a novolak resin using a diazoquinone type as a photosensitizer is capable of forming a pattern with excellent resolution because it does not swell at the time of development. Therefore, it is frequently used in the production of the above-mentioned semiconductor microcircuits.
[0003]
On the other hand, even in photosensitive heat-resistant resin compositions such as photosensitive polyimide used for semiconductor insulating films and protective films, positive-type photosensitive heat-resistant resin compositions having characteristics such as high resolution and non-pollution of developer. Has been developed in the same manner as photoresists (for example, Japanese Patent Laid-Open No. 63-96162, Japanese Patent Publication No. 1-46862), and is attracting attention as a highly integrated semiconductor insulating film and resin for protective films. Many of the positive photosensitive resins are obtained by adding a photosensitive agent such as a diazoquinone compound as described above to an alkali-soluble polymer. In the unexposed area, these diazoquinone compounds and the like are insoluble in the alkaline aqueous solution, but undergo a chemical change upon exposure and become soluble in the alkaline aqueous solution. For this reason, making use of this exposure / unexposed solubility difference, the coating film of the resin composition to which this compound is added is exposed and then treated with an alkaline aqueous solution, thereby creating a coating pattern only in the unexposed area. Is possible.
[0004]
Unlike the photoresist made of novolak resin, the positive photosensitive heat-resistant resin composition described in JP-A-63-96162 and JP-B-1-46862 is permanent as an insulating film or protective film. It remains in the semiconductor. A photoresist made of novolak resin is exposed and developed and peeled off immediately after pattern formation. A photosensitive heat resistant resin composition is heat-treated at a temperature of about 300 to 400 ° C. after development, and has excellent thermal stability. It is a common curing process to convert to After that, apply a photoresist, pattern it, use this as a mask, etch the glass inorganic protective film by reactive ion etching (RIE), etc., then peel off the photoresist, and mold epoxy resin, phenol resin, silicone resin, etc. The material is molded by casting, transfer formation or the like.
[0005]
In the above process, since the photosensitive resin composition is not directly exposed by RIE or the like, there is no damage during etching. However, in recent years, the photosensitive resin composition is etched instead of a mask without applying a photoresist. (Japanese Patent Application No. 10-060800). In this process, since the photosensitive resin composition remains permanently, the surface of the photosensitive resin composition is likely to be uneven due to damage during etching, and the appearance is poor. Occasionally, there was a problem that the sealing could not be completely completed between the recesses and a gap was formed, and cracks were likely to be generated from the gap during a reliability test (such as during moisture absorption treatment).
[0006]
[Problems to be solved by the invention]
The present invention provides a processing method that significantly reduces damage during etching of a photosensitive resin composition.
[0007]
[Means for Solving the Problems]
In the present invention, after creating a pattern with a photosensitive resin composition comprising a polybenzoxazole precursor and a photosensitive diazoquinone, the pattern is cured at a temperature higher than the pre-bake temperature, but lower than the final curing temperature, and then etched. And a final curing method for the photosensitive resin composition.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
The present invention has found a processing method with less damage during etching by performing curing (pre-etch baking) at a temperature higher than the pre-baking temperature and lower than the final curing temperature after the pattern formation and before the etching. Although details of this reason are not yet clear, since polybenzoxazole is a polymerized resin, it is present at or near the precursor of polybenzoxazole at the time of pattern formation. When heated to ˜400 ° C., the polymerization reaction is completed, and an oxazoline ring is formed and a tough film is obtained. When this oxazoline ring is formed, the flexibility of polybenzoxazole is limited. When etching is performed in this state, the composition having higher fluidity than polybenzoxazole is etched first, and the resin surface becomes uneven. In order to reduce the unevenness, it has been found that a method of setting the temperature so as not to form an oxazole ring completely is preferable.
[0009]
In this state, the flexibility of the resin composition itself is not significantly limited, and the difference in etching rate during etching is reduced, and the unevenness is reduced. The pre-etch bake temperature is better when it is close to the pre-bake temperature in terms of reducing unevenness, but the residual solvent is volatilized during etching and the etcher is likely to contaminate and the etching amount is large. Therefore, it is necessary to use properly depending on the use because there is a problem that it is easy to deposit on the resin surface and opening of the wafer. Good conditions are between 120 ° C and 250 ° C. More preferably, it is between 150 ° C and 200 ° C. If the temperature is lower than 120 ° C, the temperature becomes the same as or lower than the pre-baking temperature after the resin coating, and there is a problem that there is almost no thermal effect and the etcher and the like are seriously contaminated. There is a problem that the effect of etch baking hardly appears and the unevenness of the surface becomes remarkable during etching.
[0010]
Further, the unevenness at the time of etching appears more prominently as the film thickness to be etched increases. However, the film thickness range is not particularly limited because the film thickness range varies depending on the etching method, gas composition, power, and the like.
[0011]
After etching is completed under the above conditions, it is necessary to perform final curing. The previous pre-etch bake is merely an improvement measure against etching, and does not provide stability of the resin itself. The final curing needs to be cured at a temperature at which the oxazole ring is formed, requires a temperature of 250 ° C. or higher, and is preferably in the range of 300 ° C. to 400 ° C. If the final curing temperature is less than 250 ° C., the cyclization reaction is insufficient, the mechanical properties are brittle, and other physical properties are remarkably lowered.
[0012]
The polybenzoxazole precursor used in the present invention is represented by the general formula (1). The polybenzoxazole precursor of the formula (1) comprises a bisphenol having an X structure, a dicarboxylic acid having a Y structure, a terminal treating agent having an E structure, and, if necessary, a modifying agent having a Z structure. When this polybenzoxazole precursor is heated at about 250 to 400 ° C., the ring is closed, and the polybenzoxazole precursor is changed to polybenzoxazole having high heat resistance.
[Chemical 7]

[0013]
Examples of X in formula (1) include the following, but are not particularly limited thereto.
[Chemical 8]

[0014]
Examples of Y in formula (1) include the following, but are not particularly limited thereto.
[Chemical 9]

[0015]
Examples of E in formula (1) include, but are not limited to, the following.
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[0016]
Furthermore, examples of Z in the formula (1) include the following, but are not particularly limited thereto.
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[0017]
In addition, in using these X, Y, E, and Z, one type or a mixture of two or more types may be used.
[0018]
The positive resin composition of the present invention is based on the polybenzoxazole precursor represented by the general formula (1) as a main component and a positive photosensitive agent.
The positive photosensitive agent used in the present invention is a diazoquinone compound having a 1,2-benzoquinonediazide or 1,2-naphthoquinonediazite structure. These are known materials disclosed in US Pat. Nos. 2,772,972, 2,797,213, and 3,669,658.
[0019]
Positive resists in which these quinonediazide compounds are blended with novolak resins are currently being used extensively for the production of circuits on semiconductor chips. That is, since the quinonediazide compound has the ability to inhibit dissolution, it can reduce the solubility of the novolak resin and provide a relief pattern with a high residual film.
However, as disclosed in Japanese Examined Patent Publication No. 1-46862, some quinonediazide compounds effective for novolak resins have no effect on polybenzoxazole precursors and have a low dissolution inhibiting ability. If the dissolution inhibiting ability is low, the remaining film rate is low and a good pattern shape cannot be obtained. Although the following are mentioned as a quinonediazide compound used by this invention, It does not specifically limit to these.
[0020]
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[0021]
If necessary, a dihydropyridine derivative for enhancing the photosensitivity can be added to the positive photosensitive resin composition used in the present invention. Examples of the dihydropyridine derivative include 2,6-dimethyl-3,5-diacetyl-4- (2′-nitrophenyl) -1,4-dihydropyridine, 4- (2′-nitrophenyl) -2,6-dimethyl- 3,5-dicarboethoxy-1,4-dihydropyridine, 4- (2 ′, 4′-dihydrophenyl) -2,6-dimethyl-3,5-dicarbomethoxy-1,4-dihydropyridine, etc. I can do it.
[0022]
In the positive photosensitive resin composition used in the present invention, a dissolution accelerator can be blended in order to enhance sensitivity characteristics and improve the solubility of the exposed area. Examples of the dissolution accelerator include the following phenol compounds, but are not particularly limited thereto.
[0023]
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[0024]
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[0025]
The positive photosensitive resin composition used in the present invention contains an organosilicon compound represented by general formulas (4), (5), and (6), a positive photosensitive resin cured film, a silicon wafer, and a semiconductor encapsulation. Formulated to improve adhesion to cured epoxy resin. The organosilicon compounds may be used alone or in combination. On the other hand, if the amount used is too small, the effect of improving the adhesiveness cannot be obtained, and if it is too large, the mechanical strength of the positive photosensitive resin cured film is lowered and the stress relaxation effect is reduced.
[0026]
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[0027]
The organosilicon compounds represented by the general formulas (4) and (5) are prepared by reacting an acid (2) anhydride and an amino group-containing silane coupling agent in an organic solvent at 20 to 100 ° C. for 30 minutes to 10 hours. Is obtained.
[0028]
Examples of the acid anhydride include maleic anhydride, succinic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylhymic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic acid, and phthalic anhydride. However, it is not particularly limited to these.
[0029]
Examples of the acid dianhydride include pyromellitic dianhydride, benzene-1,2,3,4-tetracarboxylic dianhydride, 3,3 ′, 4,4′-benzophenone tetracarboxylic dianhydride, 2,2 ′, 3,3′-benzophenonetetracarboxylic dianhydride, 2,3,3 ′, 4′-benzophenonetetracarboxylic dianhydride, naphthalene-, 2,3,6,7-tetracarboxylic acid Dianhydride, naphthalene-1,2,4,5-tetracarboxylic dianhydride, naphthalene-1,4,5,8-tetracarboxylic dianhydride, naphthalene-1,2,6,7-tetracarboxylic Acid dianhydride, 4,8-dimethyl-1,2,3,5,6,7-hexahydronaphthalene-1,2,5,6-tetracarboxylic dianhydride, 4,8-dimethyl-1, 2,3,5,6,7-hexahydronaphthalene-2 3,6,7-tetracarboxylic dianhydride, 2,6-dichloronaphthalene-1,4,5,8-tetracarboxylic dianhydride, 2,7-dichloronaphthalene-1,4,5,8- Tetracarboxylic dianhydride, 2,3,6,7-tetrachloronaphthalene-1,4,5,8-tetracarboxylic dianhydride, 3,3 ′, 4,4′-diphenyltetracarboxylic dianhydride 2,2 ', 3,3'-diphenyltetracarboxylic dianhydride, 2,3,3', 4'-diphenyltetracarboxylic dianhydride, 3,3 ", 4,4" -p- Terphenyltetracarboxylic dianhydride, 2,2 ", 3,3" -p-terphenyltetracarboxylic dianhydride, 2,3,3 ", 4" -p-terphenyltetracarboxylic dianhydride 2,2-bis (2,3-dicarboxyphenyl) -propane 2,2-bis (3,4-dicarboxyphenyl) -propane dianhydride, bis (2,3-dicarboxyphenyl) ether dianhydride, bis (3,4-dicarboxyphenyl) ether dianhydride Bis (2,3-dicarboxyphenyl) methane dianhydride, bis (3,4-dicarboxyphenyl) methane dianhydride, bis (2,3-dicarboxyphenyl) sulfone dianhydride, 1,1 -Bis (2,3-dicarboxyphenyl) ethane dianhydride, 1,1-bis (3,4-dicarboxyphenyl) ethane dianhydride, perylene-2,3,8,9-tetracarboxylic dianhydride Perylene-3,4,9,10-tetracarboxylic dianhydride, perylene-4,5,10,11-tetracarboxylic dianhydride, perylene-5,6,11,12-tetracarboxylic dianhydride Nothing Water, phenanthrene-1,2,7,8-tetracarboxylic dianhydride, phenanthrene-1,2,6,7-tetracarboxylic dianhydride, phenanthrene-1,2,9,10-tetracarboxylic acid Dianhydride, pyrazine-2,3,5,6-tetracarboxylic dianhydride, pyrrolidine-2,3,4,5-tetracarboxylic dianhydride, thiophene-2,3,4,5-tetracarboxylic Examples of the acid dianhydride and 4,4′-hexafluoroisopropylidenediphthalic dianhydride include, but are not limited to.
[0030]
Examples of the silane coupling agent having an amino group include γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropylmethyldiethoxysilane, γ-aminopropylmethyldimethoxysilane, and γ-aminopropylethyldimethoxysilane. Silane, γ-aminopropylethyldiethoxysilane, γ-aminopropyldimethylmethoxysilane, γ-aminopropyldimethylethoxysilane, γ-aminopropylethyldiethoxysilane, γ-aminopropylethylmethoxysilane, γ-aminopropyldiethylethoxy Silane, N- (β-aminoethyl) -γ-aminopropyltrimethoxysilane, N- (β-aminoethyl) -γ-aminopropylmethyldimethoxysilane, 4-aminobutyldimethylmethoxysilane and the like. It is, but is not particularly limited thereto.
[0031]
The organosilicon compound represented by the general formula (6) is obtained by reacting an epoxy group-containing silane coupling agent and tetracarboxylic dianhydride at 20 to 100 ° C. for 30 minutes to 10 hours.
Examples of the acid dianhydride include those similar to the case of the organosilicon compound of the general formula (4), but are not particularly limited thereto. As silane coupling agents, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropylethyldiethoxysilane, γ-glycidoxypropyldimethylmethoxysilane, γ-glycidoxypropyldimethylethoxysilane, γ-glycidoxypropyldiethylmethoxysilane, γ-glycidoxypropyldiethylethoxysilane However, the present invention is not particularly limited thereto.
[0032]
The organosilicon compounds represented by the above general formulas (4), (5), and (6) are obtained by reacting and impart excellent properties to the positive photosensitive resin composition containing the organic silicon compound. However, excellent characteristics can also be expressed by blending each raw material as it is without reacting.
[0033]
If necessary, additives such as a leveling agent and a silane coupling agent can be added to the positive photosensitive resin composition used in the present invention. Various solvents are used to form a varnish. As the solvent, N-methyl-2-pyrrolidone, γ-butyrolactone, N, N-dimethylacetamide, dimethyl sulfoxide, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, Dipropylene glycol monomethyl ether acetate, methyl lactate, ethyl lactate, butyl lactate, methyl-1,3-dibutylene glycol acetate, 1,3-dibutylene glycol-3-monomethyl ether, methyl puruvate, ethyl puruvate, methyl Although 3-methoxypropionate etc. are mentioned, it is not limited to this. Moreover, you may use a solvent individually or in mixture.
[0034]
In the method of using the positive photosensitive resin composition of the present invention, the composition is first applied to a suitable support such as a silicon wafer, a ceramic substrate, an aluminum substrate and the like. Examples of the coating method include spin coating using a spinner, spray coating using a spray coater, dipping, printing, roll coating, and the like. Next, after prebaking at 60 to 130 ° C. to dry the coating film, actinic radiation is applied to the desired pattern shape. As the actinic radiation, X-rays, electron beams, ultraviolet rays, visible rays and the like can be used, but those having a wavelength of 200 to 500 nm are preferable. Next, a relief pattern is obtained by dissolving and removing the irradiated portion with a developer. Developers include inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia, primary amines such as ethylamine and n-propylamine, diethylamine, and di-n. Secondary amines such as propylamine, tertiary amines such as triethylamine and methyldiethylamine, alcohol amines such as dimethylethanolamine and triethanolamine, quaternary ammonium such as tetramethylammonium hydroxide and tetraethylammonium hydroxide An aqueous solution of an alkali such as a salt and an aqueous solution to which an appropriate amount of a water-soluble organic solvent such as methanol or ethanol or a surfactant is added can be preferably used. As a developing method, methods such as spraying, paddle, dipping, and ultrasonic waves are possible. Next, the relief pattern formed by development is rinsed. Distilled water or the like is used as the rinse liquid. Thereafter, pre-etch baking is performed. Pre-etch baking is performed at a temperature equal to or higher than pre-baking, preferably 120 to 250 ° C. The dryer is not particularly limited as long as high-temperature heat treatment is possible, such as an oven furnace, a furnace, a hot plate, or the like. Next, the glass inorganic protective film or the like is etched by reactive ion etching (RIE) or the like using a positive resin as a mask, and then heat treatment is performed to form an oxazole ring, thereby obtaining a final pattern with high heat resistance. The heating temperature is preferably 250 ° C. or higher, more preferably 300 ° C. to 400 ° C. in terms of forming an oxazole ring, but sufficient performance can be obtained by baking for a long time even at 250 ° C. or lower. Will increase production time. The oxygen concentration is preferably 5% or less under a nitrogen purge, and more preferably 1% or less as described above. According to the type of dryer, it is preferable to have a low oxygen concentration of 1000 ppm or less. In this case, since it is difficult to oxidize, it can be cured at a higher temperature, and the heat resistance of the photosensitive resin can be improved. Become.
[0035]
The photosensitive resin composition according to the present invention is useful not only for semiconductor applications but also as interlayer insulation for multilayer circuits, cover coats for flexible copper-clad plates, solder resist films, liquid crystal alignment films, and the like.
A semiconductor device manufactured using the method for processing a photosensitive resin composition of the present invention is a highly reliable semiconductor device. Conventionally known methods can be used for the manufacturing method of the semiconductor device excluding this processing method.
[0036]
【Example】
Hereinafter, the present invention will be described specifically by way of examples.
Example 1
* Synthesis of polyamide
443.2 g (0.9 mol) of a dicarboxylic acid derivative obtained by reacting 1 mol of diphenyl ether-4,4′-dicarboxylic acid with 2 mol of 1-hydroxy-1,2,3-benzotriazole and hexafluoro- 36,3 g (1.0 mol) of 2,2-bis (3-amino-4-hydroxyphenyl) propane and a four-neck separable equipped with a thermometer, stirrer, raw material inlet, and dry nitrogen gas inlet tube It put into the flask and 3000 g of N-methyl-2-pyrrolidone was added and dissolved. Thereafter, the mixture was reacted at 75 ° C. for 12 hours using an oil bath.
Next, 32.8 g (0.2 mol) of 5-norbornene-2,3-dicarboxylic anhydride dissolved in 500 g of N-methyl-2-pyrrolidone was added, and the mixture was further stirred for 12 hours to complete the reaction. After filtering the reaction mixture, the reaction mixture was put into a solution of water / methanol = 3/1, the precipitate was collected by filtration, washed thoroughly with water, and dried under vacuum to obtain the target polyamide (A-1). Obtained.
[0037]
* Preparation of positive photosensitive resin composition
100 g of synthesized polyamide (A-1), 25 g of diazoquinone (B1) having the structure of the following formula, 10 g of phenol compound (P1) having the structure of the following formula, 5 g of (P2), γ-aminopropyltriethoxysilane and anhydrous maleic 2 g of an organosilicon acid compound obtained by reacting an acid, an organosilicon compound obtained by reacting γ-aminopropyltriethoxysilane with 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride 1 g was dissolved in 250 g of N-methyl-2-pyrrolidone, and then filtered through a 0.2 μm Teflon filter to obtain a photosensitive resin composition.
[0038]
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[0039]
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[0040]
* Create pattern
This positive photosensitive resin composition was applied onto a silicon wafer using a spin coater and then dried on a hot plate at 120 ° C. for 4 minutes to obtain a coating film having a thickness of about 5 μm. 50 mJ / cm is passed through the reticle on this coating film using a g-line stepper exposure machine NSR-1505G3A (Nikon Corporation). ² To 10mJ / cm ² Increase by 540mJ / cm ² Until exposure.
Next, the exposed portion was dissolved and removed by immersing in a 1.40% tetramethylammonium hydroxide aqueous solution for 60 seconds, and then rinsed with pure water for 30 seconds. As a result, the exposure amount is 230 mJ / cm. ² It was confirmed that the pattern was formed from the portion irradiated with. (Sensitivity is 230mJ / cm ² ). The residual film ratio (film thickness after development / film thickness before development × 100) at this time was 93.1%, which was a very high value (the resin in this state is referred to as EX1). The developed wafer prepared here was cured at 130 ° C. for 90 minutes, and then subjected to oxygen plasma treatment at 1000 W for 2 minutes using an etching apparatus OPM-EM1000 (manufactured by Tokyo Ohka Kogyo Co., Ltd.).
The film thickness after the treatment was about 3 μm. The resin surface was in good condition with no abnormalities.
[0041]
Further, a coating film having a film thickness of 15 μm after pre-baking was obtained by the same application as described above, and then developed in the same manner as described above without exposure (the resin in this state is NEX1) and cured at 130 ° C. for 90 minutes. Then, oxygen plasma treatment was performed at 1000 W for 2 minutes using an etching apparatus OPM-EM1000 (manufactured by Tokyo Ohka Kogyo Co., Ltd.). This wafer was cured at 320 ° C. for 30 minutes, and a cured film was obtained after peeling from the wafer.
Tensilon was used to evaluate the tensile properties of the cured film. Tensile strength is 12.5kg / mm ² The tensile elastic modulus is 256kg / mm ² The tensile elongation was as high as 45%, and no decrease in strength due to plasma damage was observed.
[0042]
Example 2
The post-development wafers (EX1 and NEX1) prepared in Example 1 were cured at 200 ° C. for 60 minutes, and then etched for 2 minutes at 1000 W using an etching apparatus OPM-EM1000 (manufactured by Tokyo Ohka Kogyo Co., Ltd.). Plasma treatment was performed.
The film thickness of EX1 was about 3.2 μm, and the resin surface was excellent without any particular abnormality. NEX1 was evaluated for tensile properties after curing as in Example 1. The tensile strength is 12.3kg / mm ² The tensile elastic modulus is 263kg / mm ² The tensile elongation was as high as 52%, and no decrease in strength due to plasma damage was observed.
[0043]
Example 3
After the developed wafers (EX1 and NEX1) prepared in Example 1 were cured at 225 ° C. for 60 minutes, oxygen was used at 1000 W for 2 minutes using an etching apparatus OPM-EM1000 (manufactured by Tokyo Ohka Kogyo Co., Ltd.). Plasma treatment was performed.
The film thickness of EX1 was about 3.2 μm, and the resin surface was excellent without any particular abnormality. NEX1 was evaluated for tensile properties after curing as in Example 1. Tensile strength is 12.5kg / mm ² The tensile modulus is 259kg / mm ² The tensile elongation was as high as 49%, and no decrease in strength due to plasma damage was observed.
[0044]
Example 4
The post-development wafers (EX1 and NEX1) prepared in Example 1 were cured at 250 ° C. for 30 minutes, and then oxygenated at 1000 W for 2 minutes using an etching apparatus OPM-EM1000 (manufactured by Tokyo Ohka Kogyo Co., Ltd.). Plasma treatment was performed.
The film thickness of EX1 was about 3.3 μm, and the resin surface was excellent without any particular abnormality. NEX1 was evaluated for tensile properties after curing as in Example 1. Tensile strength is 12.7kg / mm ² The tensile modulus is 248kg / mm ² The tensile elongation was as high as 45%, and no strength reduction was observed due to plasma damage.
[0045]
Example 5
In the synthesis of the polyamide in Example 1, instead of the dicarboxylic acid derivative obtained by reacting 1 mol of diphenyl ether-4,4′-dicarboxylic acid with 2 mol of 1-hydroxy-1,2,3-benzotriazole, A polyamide (A-2) was synthesized using a dicarboxylic acid derivative obtained by reacting 1 mol of diphenylsulfone-4,4′-dicarboxylic acid with 2 mol of 1-hydroxy-1,2,3-benzotriazole. The other evaluations were the same as in Example 1.
[0046]
Example 6
In the synthesis of the polyamide in Example 1, 3,3′-diamino-4,4′-dihydroxydiphenyl sulfone was used instead of hexafluoro-2,2-bis (3-amino-4-hydroxyphenyl) propane, and the polyamide (A-3) was synthesized and the others were evaluated in the same manner as in Example 1.
[0047]
<< Comparative Example 1 >>
After the developed wafers (EX1 and NEX1) prepared in Example 1 were cured at 350 ° C. for 60 minutes, oxygen was used at 1000 W for 2 minutes using an etching apparatus OPM-EM1000 (manufactured by Tokyo Ohka Kogyo Co., Ltd.). Plasma treatment was performed.
The film thickness of EX1 was about 3.7 μm, and the resin surface had many holes of about 2 to 10 μm. NEX1 was evaluated for tensile properties after curing as in Example 1. Tensile strength is 10.9kg / mm ² The tensile modulus is 232kg / mm ² The tensile elongation was as low as 18%, and a decrease in strength due to plasma damage was observed.
[0048]
<< Comparative Example 2 >>
After the developed wafers (EX1 and NEX1) prepared in Example 5 were cured at 380 ° C. for 30 minutes, oxygen was used at 1000 W for 2 minutes using an etching apparatus OPM-EM1000 (manufactured by Tokyo Ohka Kogyo Co., Ltd.). Plasma treatment was performed.
The film thickness of EX1 was about 3.8 μm, and the resin surface had many holes of about 2 to 10 μm. NEX1 was evaluated for tensile properties after curing as in Example 1. Tensile strength is 10.4kg / mm ² The tensile elastic modulus is 221kg / mm ² The tensile elongation was as low as 15%, and a decrease in strength due to plasma damage was observed.
[0049]
<< Comparative Example 3 >>
After the developed wafers (EX1 and NEX1) prepared in Example 1 were cured at 320 ° C. for 30 minutes, oxygen was used at 1000 W for 2 minutes using an etching apparatus OPM-EM1000 (manufactured by Tokyo Ohka Kogyo Co., Ltd.). Plasma treatment was performed.
The film thickness of EX1 was about 3.5 μm, and the resin surface had a few holes of about 1 to 3 μm. NEX1 was evaluated for tensile properties after curing as in Example 1. Tensile strength is 11.3kg / mm ² The tensile elastic modulus is 242kg / mm ² The tensile elongation was 32%, and a slight decrease in strength due to plasma damage was observed.
[0050]
Table 1 shows the evaluation results of Examples 1 to 6 and Comparative Examples 1 to 3.
[Table 1]

[0051]
【The invention's effect】
According to the present invention, it is possible to reduce resin damage during etching of a photosensitive resin composition on a semiconductor.

Claims (7)

 A photosensitive resin composition consisting of a polybenzoxazole precursor and a photosensitive diazoquinone compound is applied, prebaked, exposed and developed to create a pattern, and then cured at a temperature higher than the prebaking temperature, but lower than the final curing temperature. (Hereinafter referred to as “pre-etch bake”), then etching, and final curing of the photosensitive resin composition.  The method for processing a photosensitive resin composition according to claim 1, wherein the temperature of the pre-etch baking is 120 ° C. to 250 ° C.  The method for processing a photosensitive resin composition according to claim 1, wherein the temperature at the final curing is 250 ° C. or more. The processing method of the photosensitive resin composition of Claim 1, 2, or 3 in which this polybenzoxazole precursor is chosen from General formula (1).

 The photosensitive resin composition according to claim 1, 2, or 3, wherein the polybenzoxazole precursor comprises 100 parts by weight of a polyamide represented by the general formula (1) and 1 to 100 parts by weight of a photosensitive diazoquinone compound (B). Processing method of things. The polybenzoxazole precursor is composed of 100 parts by weight of a polyamide represented by the general formula (1), 1 to 100 parts by weight of a photosensitive diazoquinone compound (B), and a phenol represented by the general formulas (2) and / or (3). The processing method of the photosensitive resin composition of Claim 1, 2, or 3 which consists of 1-50 weight part of compounds (C).

The polybenzoxazole precursor comprises 100 parts by weight of a polyamide represented by the general formula (1), 1 to 100 parts by weight of a photosensitive diazoquinone compound (B), and a phenol represented by the general formulas (2) and / or (3). One or more organosilicon compounds (D) 0.1 selected from the group consisting of 1 to 50 parts by weight of the compound (C) and the organosilicon compounds represented by the general formulas (4), (5) and (6) The processing method of the photosensitive resin composition of Claim 1, 2, or 3 which consists of -20 weight part.