JP4316222B2 - Resist pattern thickening material, resist pattern and manufacturing method thereof, and semiconductor device and manufacturing method thereof - Google Patents

Description

【００８９】
−レジストパターン及びその製造−
以上により調製した本発明のレジストパターン厚肉化材料１Ａ〜１Ｊを、前記ＡｒＦレジスト（住友化学（株）製、ＰＡＲ７００、脂環族系レジスト）により形成したホールパターン上に、スピンコート法により、初めに１０００ｒｐｍ／５ｓの条件で、次に３５００ｒｐｍ／４０ｓの条件で塗布した後、８５℃／７０ｓの条件で前記プリベークを行い、更に１１０℃／７０ｓの条件で前記架橋ベークを行った後、純水でレジストパターン厚肉化材料１Ａ〜１Ｊを６０秒間リンスし、未架橋部を除去し、レジストパターン厚肉化材料１Ａ〜１Ｊにより厚肉化したレジストパターンを現像させることにより、レジストパターンを製造した。
【００９０】
製造したレジストパターン（厚肉化されたレジストパターン）により形成されたパターンのサイズ（厚肉化後のレジストパターンにより形成されたレジスト抜けパターンのサイズ）について、初期パターンにより形成されたパターンのサイズ（厚肉化前のレジストパターンにより形成されたレジスト抜けパターンのサイズ）と共に表２に示した。なお、表２において、「１Ａ」〜「１Ｊ」は、前記レジストパターン厚肉化材料１Ａ〜１Ｊに対応する。
【００９１】
【表２】

【００９２】
以上により調製した本発明のレジストパターン厚肉化材料１Ａ〜１Ｊを、前記ＡｒＦレジスト（住友化学（株）製、ＰＡＲ７００）により形成したライン＆スペースパターン上に、スピンコート法により、初めに１０００ｒｐｍ／５ｓの条件で、次に３５００ｒｐｍ／４０ｓの条件で塗布した後、８５℃／７０ｓの条件で前記プリベークを行い、更に１１０℃／７０ｓの条件で前記架橋ベークを行った後、純水でレジストパターン厚肉化材料１Ａ〜１Ｊを６０秒間リンスし、未架橋部を除去し、レジストパターン厚肉化材料１Ａ〜１Ｊにより厚肉化したレジストパターンを現像させることにより、レジストパターンを製造した。
【００９３】
製造したレジストパターン（厚肉化されたレジストパターン）により形成されたパターンのサイズ（厚肉化後のレジストパターンにより形成されたレジスト抜けパターンのサイズ）について、初期パターンにより形成されたパターンのサイズ（厚肉化前のレジストパターンにより形成されたレジスト抜けパターンのサイズ）と共に表３に示した。なお、表３において、「１Ａ」〜「１Ｊ」は、前記レジストパターン厚肉化材料１Ａ〜１Ｊに対応する。
【００９４】
【表３】

【００９５】
表２及び表３の結果より、本発明のレジストパターン厚肉化材料は、ホールパターン、ライン＆スペースパターンのいずれに対しても、適用可能であり、厚肉化可能であることが判る。本発明のレジストパターン厚肉化材料を、ホールパターンの形成に用いると、該ホールパターン内径を狭く微細にすることができ、また、線状パターンの形成に用いると、該線状パターン幅（該線状パターンを形成するレジストパターン相互の間隔）を小さく微細にすることができ、また、孤立パターンの形成に用いると、該孤立パターンの面積を大きくすることができる。
【００９６】
次に、シリコン基板上に形成したレジストの表面に、本発明のレジストパターン厚肉化材料１Ｄ、１Ｈ、１Ｉ、１Ｊを塗布し架橋させて厚みが０．５μｍである表層を形成した。これらの表層と、比較のための前記ＫｒＦレジスト（シプレイ社製、ＵＶ−６）と、比較のためのポリメチルメタクリレート（PMMA）とに対し、エッチング装置（平行平板型ＲＩＥ装置、富士通（株）製）を用いて、Ｐμ＝２００W、圧力＝０．０２Ｔｏｒｒ、ＣＦ_４ガス＝１００ｓｃｃｍの条件下で３分間エッチングを行い、サンプルの減膜量を測定し、エッチングレートを算出し、前記ＫｒＦレジストのエッチングレートを基準として相対評価を行った。
【００９７】
【表４】

【００９８】
表４に示す結果から、本発明のレジストパターン厚肉化材料のエッチング耐性は、前記ＫｒＦレジストに近く、前記ＰＭＭＡより顕著に優れていることが判る。
【００９９】
次に、本発明のレジストパターン厚肉化材料１Ａ〜１Ｊを、露光後１ヶ月間クリーンルーム外に放置したウエハ基板上の内層レジストパターン上に塗布したところ、露光後すぐに塗布した場合と同様のレジストパターン厚肉化効果が得られた。
この結果により、本発明のレジストパターン厚肉化材料は、従来におけるＲＥＬＡＣＳと呼ばれる技術のような、酸の拡散による架橋反応を利用して前記内層レジストパターンを厚肉化するのではなく、前記レジストパターンとの間の相溶性に依存して該レジストパターンを厚肉化しているもと推測される。
【０１００】
（実施例２）
−レジストパターン厚肉化材料の調製−
表５に示す組成を有する本発明のレジストパターン厚肉化材料２Ａ〜２Ｍを調製した。なお、表５において、カッコ内の数値の単位は、質量部を表す。「樹脂」の欄における、「樹脂１」、「樹脂２」及び「樹脂３」は後述の通り合成したものであり、「架橋剤」の欄における、「ウリル」は、テトラメトキシメチルグリコールウリルを表し、「ユリア」は、Ｎ、Ｎ’−ジメトキシメチルジメトキシエチレンユリアを表し、「メラミン」は、ヘキサメトキシメチルメラミンを表す。「界面活性剤」の欄における「ＴＮ−８０」は、非イオン性界面活性剤（旭電化社製、第１級アルコールエトキシレート系界面活性剤）を表す。また、前記樹脂、前記架橋剤及び前記界面活性剤を除いた主溶剤成分として、純水（脱イオン水）とイソプロピルアルコールとの混合液（質量比が純水（脱イオン水）：イソプロピルアルコール＝１６：０．７５）を使用した。
【０１０１】
前記「樹脂１」は、以下のようにして合成した「ポリビニルβ−レゾルシンアセタール樹脂」である。即ち、ポリビニルアルコール５００（関東化学製）１０ｇを脱イオン水１００ｇに溶解させ、濃塩酸０．８ｇを入れて４０℃で３時間攪拌した。これにβ―レゾルシンアルデヒド（東京化成製）２．３６ｇを加え、そのままの温度で６時間攪拌した。反応溶液を室温に戻し、１５質量％のTMAH(テトラメチルアンモニウムハイドロオキサイド)溶液を加え、中和した。この溶液を２Lエタノールに滴下し、樹脂を分離した。ガラスフィルタで樹脂を濾別し、４５℃の真空ベーク炉で６時間減圧乾燥させた。この操作を３度繰り返し、目的とするポリビニルβ−レゾルシンアセタール樹脂を合成した。収量は６．８ｇであった。ＮＭＲによりアセタール化率を求めたところ、２０．６ｍｏｌ％であった。
【０１０２】
前記「樹脂２」は、以下のようにして合成した「ポリビニル−２，３−ジヒドロキシベンズアセタール樹脂」である。即ち、前記「樹脂１」の合成において、β−レゾルシンアルデヒドを２，３−ジヒドロシキベンズアルデヒドに代えた以外は「樹脂１」の合成と同様にして、２，３−ジヒドロキシベンズアセタール樹脂を得た。収量は６．６ｇであった。ＮＭＲによりアセタール化率を求めたところ、２０．１ｍｏｌ％であった。
【０１０３】
前記「樹脂３」は、以下のようにして合成した「ポリビニルβ−レゾルシンアセタール樹脂」である。即ち、ポリビニルアルコール５００（関東化学社製）１０ｇを脱イオン水１００ｇに溶解させ、濃塩酸０．４ｇを入れて４０℃で３時間撹拌した。これにβ−レゾルシンアルデヒド（東京化成社製）０．５ｇを加え、そのままの温度で６時間攪拌した。反応溶液を室温に戻し、１５質量％のTMAH(テトラメチルアンモニウムハイドロオキサイド)溶液を加え、中和した。この溶液を２Lのエタノールに滴下し、樹脂を分離した。ガラスフィルタで樹脂を濾別し、４５℃の真空ベーク炉で６時間減圧乾燥させた。この操作を３度繰り返し、目的とするポリビニルβ−レゾルシンアセタール樹脂を得た。収量は４．１ｇであった。NMRにより、アセタール化率を求めたところ、３．７mol％であった。
【０１０４】
【表５】

【０１０５】
−レジストパターン及びその製造−
以上により調製した本発明のレジストパターン厚肉化材料２Ａ〜２Ｌを、前記ＡｒＦレジスト（住友化学（株）製、ＰＡＲ７００）により形成したホールパターン上に、スピンコート法により、初めに１０００ｒｐｍ／５ｓの条件で、次に３５００ｒｐｍ／４０ｓの条件で塗布した後、８５℃／７０ｓの条件で前記プリベークを行い、更に１１０℃／７０ｓの条件で前記架橋ベークを行った後、純水でレジストパターン厚肉化材料２Ａ〜２Ｌを６０秒間リンスし、未架橋部を除去し、レジストパターン厚肉化材料２Ａ〜２Ｌにより厚肉化したレジストパターンを現像させることにより、レジストパターンを製造した。
【０１０６】
製造したレジストパターン（厚肉化されたレジストパターン）により形成されたパターンのサイズについて、初期パターンサイズ（厚肉化する前の前記ホールパターンのサイズ）により形成されたパターンのサイズと共に表６に示した。なお、表６において、「２Ａ」〜「２Ｌ」は、前記レジストパターン厚肉化材料２Ａ〜２Ｌに対応する。
【０１０７】
【表６】

【０１０８】
以上により調製した本発明のレジストパターン厚肉化材料２Ａ〜２Ｌを、前記ＡｒＦレジスト（住友化学（株）製、ＰＡＲ７００）により形成したライン＆スペースパターン上に、スピンコート法により、初めに１０００ｒｐｍ／５ｓの条件で、次に３５００ｒｐｍ／４０ｓの条件で塗布した後、８５℃／７０ｓの条件で前記プリベークを行い、更に１１０℃／７０ｓの条件で前記架橋ベークを行った後、純水でレジストパターン厚肉化材料２Ａ〜２Ｌを６０秒間リンスし、未架橋部を除去し、レジストパターン厚肉化材料２Ａ〜２Ｌにより厚肉化したレジストパターンを現像させることにより、レジストパターンを製造した。
【０１０９】
製造したレジストパターン（厚肉化されたレジストパターン）により形成されたパターンのサイズについて、初期パターンサイズ（厚肉化する前の前記ライン＆スペースパターンのサイズ）により形成されたパターンのサイズと共に表７に示した。なお、表７において、「２Ａ」〜「２Ｌ」は、前記レジストパターン厚肉化材料２Ａ〜２Ｌに対応する。
【０１１０】
【表７】

【０１１１】
表６及び表７の結果より、本発明のレジストパターン厚肉化材料は、ホールパターン、ライン＆スペースパターンのいずれに対しても、適用可能であり、厚肉化可能であることが判る。本発明のレジストパターン厚肉化材料を、ホールパターンの形成に用いると、該ホールパターン内径を狭く微細にすることができ、また、線状パターンの形成に用いると、該線状パターン幅（該線状パターンを形成するレジストパターン相互の間隔）を小さく微細にすることができ、また、孤立パターンの形成に用いると、該孤立パターンの面積を大きくすることができる。
【０１１２】
次に、シリコン基板上に形成したレジストの表面に、本発明のレジストパターン厚肉化材料２Ａ、２Ｇ、２Ｍを塗布し架橋させて厚みが０．５μｍである表層を形成した。これらの表層と、比較のための前記ＫｒＦレジスト（シプレイ社製、ＵＶ−６）と、比較のためのポリメチルメタクリレート（ＰＭＭＡ）とに対し、エッチング装置（平行平板型ＲＩＥ装置、富士通（株）製）を用いて、Ｐμ＝２００Ｗ、圧力＝０．０２Ｔｏｒｒ、ＣＦ_４ガス＝１００ｓｃｃｍの条件下で３分間エッチングを行い、サンプルの減膜量を測定し、エッチングレートを算出し、前記ＫｒＦレジストのエッチングレートを基準として相対評価を行った。
【０１１３】
【表８】

【０１１４】
表８に示す結果から、本発明のレジストパターン厚肉化材料のエッチング耐性は、前記ＫｒＦレジストに近く、前記ＰＭＭＡより顕著に優れていることが判る。なお、レジストパターン厚肉化材料２Ｍについては、アリールアセタールの含有量が５ｍｏｌ％未満であり、同含有量が５ｍｏｌ％以上であるレジストパターン厚肉化材料２Ａ及びＧに比しエッチング耐性がやや劣る傾向が観られた。
【０１１５】
次に、本発明のレジストパターン厚肉化材料２Ａ〜２Ｍを、露光後１ヶ月間クリーンルーム外に放置したウエハ基板上のレジストパターン上に塗布したところ、露光後すぐに塗布した場合と同様のパターン厚肉化効果が得られた。
この結果により、本発明のレジストパターン厚肉化材料は、従来におけるＲＥＬＡＣＳと呼ばれる技術のような、酸の拡散による架橋反応を利用して前記レジストパターンを厚肉化するのではなく、前記レジストパターンとの間の相溶性に依存して該レジストパターンを厚肉化しているもと推測される。
【０１１６】
（実施例３）
−フラッシュメモリ及びその製造−
実施例３は、本発明のレジストパターン厚肉化材料を用いた本発明の半導体装置及びその製造方法の一例である。なお、この実施例３では、以下のレジスト膜２６、２７、２９、３２及び３４が、本発明のレジストパターン厚肉化材料を用いて実施例１及び２におけるのと同様の方法により厚肉化されたものである。
【０１１７】
図３における（ａ）及び（ｂ）は、ＦＬＯＴＯＸ型又はＥＴＯＸ型と呼ばれるＦＬＯＴＯＸ型又はＥＴＯＸ型と呼ばれるＦＬＡＳＨ ＥＰＲＯＭの上面図（平面図）であり、図４における（ａ）〜（ｃ）、図５における（ｄ）〜（ｆ）、図６（ｇ）〜（ｉ）は、該ＦＬＡＳＨ ＥＰＲＯＭの製造方法に関する一例を説明するための断面概略図であり、図４〜図６における、左図はメモリセル部（第１素子領域）であって、フローティングゲート電極を有するＭＯＳトランジスタの形成される部分のゲート幅方向（図３におけるＸ方向）の断面（Ａ方向断面）概略図であり、中央図は前記左図と同部分のメモリセル部であって、前記Ｘ方向と直交するゲート長方向（図３におけるＹ方向）の断面（Ｂ方向断面）概略図であり、右図は周辺回路部（第２素子領域）のＭＯＳトランジスタの形成される部分の断面（図３におけるＡ方向断面）概略図である。
【０１１８】
まず、図４（ａ）に示すように、ｐ型のＳｉ基板２２上の素子分離領域に選択的にＳｉＯ_２膜によるフィールド酸化膜２３を形成した。その後、メモリセル部（第１素子領域）のＭＯＳトランジスタにおける第１ゲート絶縁膜２４ａを厚みが１００〜３００Åとなるように熱酸化にてＳｉＯ_２膜により形成し、また別の工程で、周辺回路部（第２素子領域）のＭＯＳトランジスタにおける第２ゲート絶縁膜２４ｂを厚みが１００〜５００Åとなるように熱酸化にてＳｉＯ_２膜により形成した。なお、第１ゲート絶縁膜２４ａ及び第２ゲート絶縁膜２４ｂを同一厚みにする場合には、同一の工程で同時に酸化膜を形成してもよい。
【０１１９】
次に、前記メモリセル部（図４（ａ）の左図及び中央図）にｎ型ディプレションタイプのチャネルを有するＭＯＳトランジスタを形成するため、閾値電圧を制御する目的で前記周辺回路部（図４（ａ）の右図）をレジスト膜２６によりマスクした。そして、フローティングゲート電極直下のチャネル領域となる領域に、ｎ型不純物としてドーズ量１×１０^１１〜１×１０^１４ｃｍ^−２のリン（Ｐ）又は砒素（Ａｓ）をイオン注入法により導入し、第１閾値制御層２５ａを形成した。なお、このときのドーズ量及び不純物の導電型は、ディプレッションタイプにするかアキュミレーションタイプにするかにより適宜選択することができる。
【０１２０】
次に、前記周辺回路部（図４（ｂ）の右図）にｎ型ディプレションタイプのチャネルを有するＭＯＳトランジスタを形成するため、閾値電圧を制御する目的でメモリセル部（図４（ｂ）の左図及び中央図）をレジスト膜２７によりマスクした。そして、ゲート電極直下のチャネル領域となる領域に、ｎ型不純物としてドーズ量１×１０^１１〜１×１０^１４ｃｍ^−２のリン（Ｐ）又は砒素（Ａｓ）をイオン注入法により導入し、第２閾値制御層２５ｂを形成した。
【０１２１】
次に、前記メモリセル部（図４（ｃ）の左図及び中央図）のＭＯＳトランジスタのフローティングゲート電極、及び前記周辺回路部（図４（ｃ）の右図）のＭＯＳトランジスタのゲート電極として、厚みが５００〜２０００Åである第１ポリシリコン膜（第１導電体膜）２８を全面に形成した。
【０１２２】
その後、図５（ｄ）に示すように、マスクとして形成したレジスト膜２９により第１ポリシリコン膜２８をパターニングして前記メモリセル部（図５（ｄ）の左図及び中央図）のＭＯＳトランジスタにおけるフローティングゲート電極２８ａを形成した。このとき、図５（ｄ）に示すように、Ｘ方向は最終的な寸法幅になるようにパターニングし、Ｙ方向はパターニングせずＳ／Ｄ領域層となる領域はレジスト膜２９により被覆されたままにした。
【０１２３】
次に、（図５（ｅ）の左図及び中央図）に示すように、レジスト膜２９を除去した後、フローティングゲート電極２８ａを被覆するようにして、ＳｉＯ_２膜からなるキャパシタ絶縁膜３０ａを厚みが約２００〜５００Åとなるように熱酸化にて形成した。このとき、前記周辺回路部（図５（ｅ）の右図）の第１ポリシリコン膜２８上にもＳｉＯ_２膜からなるキャパシタ絶縁膜３０ｂが形成される。なお、ここでは、キャパシタ絶縁膜３０ａ及び３０ｂはＳｉＯ_２膜のみで形成されているが、ＳｉＯ_２膜及びＳｉ_３Ｎ_４膜が２〜３積層された複合膜で形成されていてもよい。
【０１２４】
次に、図５（ｅ）に示すように、フローティングゲート電極２８ａ及びキャパシタ絶縁膜３０ａを被覆するようにして、コントロールゲート電極となる第２ポリシリコン膜（第２導電体膜）３１を厚みが５００〜２０００Åとなるように形成した。
【０１２５】
次に、図５（ｆ）に示すように、前記メモリセル部（図５（ｆ）の左図及び中央図）をレジスト膜３２によりマスクし、前記周辺回路部（図５（ｆ）の右図）の第２ポリシリコン膜３１及びキャパシタ絶縁膜３０ｂを順次、エッチングにより除去し、第１ポリシリコン膜２８を表出させた。
【０１２６】
次に、図６（ｇ）に示すように、前記メモリセル部（図６（ｇ）の左図及び中央図）の第２ポリシリコン膜３１、キャパシタ絶縁膜３０ａ及びＸ方向だけパターニングされている第１ポリシリコン膜２８ａに対し、レジスト膜３２をマスクとして、第１ゲート部３３ａの最終的な寸法となるようにＹ方向のパターニングを行い、Ｙ方向に幅約１μｍのコントロールゲート電極３１ａ／キャパシタ絶縁膜３０ｃ／フローティングゲート電極２８ｃによる積層を形成すると共に、前記周辺回路部（図６（ｇ）の右図）の第１ポリシリコン膜２８に対し、レジスト膜３２をマスクとして、第２ゲート部３３ｂの最終的な寸法となるようにパターニングを行い、幅約１μｍのゲート電極２８ｂを形成した。
【０１２７】
次に、前記メモリセル部（図６（ｈ）の左図及び中央図）のコントロールゲート電極３１ａ／キャパシタ絶縁膜３０ｃ／フローティングゲート電極２８ｃによる積層をマスクとして、素子形成領域のＳｉ基板２２にドーズ量１×１０^１４〜１×１０^１６ｃｍ^−２のリン（Ｐ）又は砒素（Ａｓ）をイオン注入法により導入し、ｎ型のＳ／Ｄ領域層３５ａ及び３５ｂを形成すると共に、前記周辺回路部（図５（ｈ）の右図）のゲート電極２８ｂをマスクとして、素子形成領域のＳｉ基板２２にｎ型不純物としてドーズ量１×１０^１４〜１×１０^１６ｃｍ^−２のリン（Ｐ）又は砒素（Ａｓ）をイオン注入法により導入し、Ｓ／Ｄ領域層３６ａ及び３６ｂを形成した。
【０１２８】
次に、前記メモリセル部（図６（ｉ）の左図及び中央図）の第１ゲート部３３ａ及び前記周辺回路部（図６（ｉ）の右図）の第２ゲート部３３ｂを、ＰＳＧ膜による層間絶縁膜３７を厚みが約５０００Åとなるようにして被覆形成した。
その後、Ｓ／Ｄ領域層３５ａ及び３５ｂ並びにＳ／Ｄ領域層３６ａ及び３６ｂ上に形成した層間絶縁膜３７に、コンタクトホール３８ａ及び３８ｂ並びにコンタクトホール３９ａ及び３９ｂを形成した後、Ｓ／Ｄ電極４０ａ及び４０ｂ並びにＳ／Ｄ電極４１ａ及び４１ｂを形成した。
以上により、図６（ｉ）に示すように、半導体装置としてＦＬＡＳＨ ＥＰＲＯＭを製造した。
【０１２９】
このＦＬＡＳＨ ＥＰＲＯＭにおいては、前記周辺回路部（図４（ａ）〜図６（ｆ）における右図）の第２ゲート絶縁膜２４ｂが形成後から終始、第１ポリシリコン膜２８又はゲート電極２８ｂにより被覆されている（図５（ｃ）〜図６（ｆ）における右図）ので、第２ゲート絶縁膜２４ｂは最初に形成された時の厚みを保持したままである。このため、第２ゲート絶縁膜２４ｂの厚みの制御を容易に行うことができると共に、閾値電圧の制御のための導電型不純物濃度の調整も容易に行うことができる。
なお、上記実施例では、第１ゲート部３３ａを形成するのに、まずゲート幅方向（図３におけるＸ方向）に所定幅でパターニングした後、ゲート長方向（図３におけるＹ方向）にパターニングして最終的な所定幅としているが、逆に、ゲート長方向（図３におけるＹ方向）に所定幅でパターニングした後、ゲート幅方向（図３におけるＸ方向）にパターニングして最終的な所定幅としてもよい。
【０１３０】
図７（ａ）〜（ｃ）に示すＦＬＡＳＨ ＥＰＲＯＭの製造例は、上記実施例において図５（ｆ）で示した工程の後が図７（ａ）〜（ｃ）に示すように変更した以外は上記実施例と同様である。即ち、図７（ａ）に示すように、前記メモリセル部図７（ａ）における左図及び中央図の第２ポリシリコン膜３１及び前記周辺回路部図７（ａ）の右図の第１ポリシリコン膜２８上に、タングステン（Ｗ）膜又はチタン（Ｔｉ）膜からなる高融点金属膜（第４導電体膜）４２を厚みが約２０００Åとなるようにして形成しポリサイド膜を設けた点でのみ上記実施例と異なる。図７（ａ）の後の工程、即ち図７（ｂ）〜（ｃ）に示す工程は、図６（ｇ）〜（ｉ）と同様に行った。図６（ｇ）〜（ｉ）と同様の工程については説明を省略し、図７（ａ）〜（ｃ）においては図６（ｇ）〜（ｉ）と同じものは同記号で表示した。
以上により、図７（ｃ）に示すように、半導体装置としてＦＬＡＳＨ ＥＰＲＯＭを製造した。
【０１３１】
このＦＬＡＳＨ ＥＰＲＯＭにおいては、コントロールゲート電極３１ａ及びゲート電極２８ｂ上に、高融点金属膜（第４導電体膜）４２ａ及び４２ｂを有するので、電気抵抗値を一層低減することができる。
なお、ここでは、高融点金属膜（第４導電体膜）として高融点金属膜（第４導電体膜）４２ａ及び４２ｂを用いているが、チタンシリサイド（ＴｉＳｉ）膜等の高融点金属シリサイド膜を用いてもよい。
【０１３２】
図８（ａ）〜（ｃ）に示すＦＬＡＳＨ ＥＰＲＯＭの製造例は、上記実施例において、前記周辺回路部（第２素子領域）（図８（ａ）における右図）の第２ゲート部３３ｃも、前記メモリセル部（第１素子領域）（図８（ａ）における左図及び中央図）の第１ゲート部３３ａと同様に、第１ポリシリコン膜２８ｂ（第１導電体膜）／ＳｉＯ_２膜３０ｄ（キャパシタ絶縁膜）／第２ポリシリコン膜３１ｂ（第２導電体膜）という構成にし、図８（ｂ）又は（ｃ）に示すように、第１ポリシリコン膜２８ｂ及び第２ポリシリコン膜３１ｂをショートさせてゲート電極を形成している点で異なること以外は上記実施例と同様である。
【０１３３】
ここでは、図８（ｂ）に示すように、第１ポリシリコン膜２８ｂ（第１導電体膜）／ＳｉＯ_２膜３０ｄ（キャパシタ絶縁膜）／第２ポリシリコン膜３１ｂ（第２導電体膜）を貫通する開口部５２ａを、例えば図８（ａ）に示す第２ゲート部３３ｃとは別の箇所、例えば絶縁膜５４上に形成し、開口部５２ａ内に第３導電体膜、例えばＷ膜又はＴｉ膜等の高融点金属膜５３ａを埋め込むことにより、第１ポリシリコン膜２８ｂ及び第２ポリシリコン膜３１ｂをショートさせている。また、図８（ｃ）に示すように、第１ポリシリコン膜２８ｂ（第１導電体膜）／ＳｉＯ_２膜３０ｄ（キャパシタ絶縁膜）を貫通する開口部５２ｂを形成して開口部５２ｂの底部に下層の第１ポリシリコン膜２８ｂを表出させた後、開口部５２ｂ内に第３導電体膜、例えばＷ膜又はＴｉ膜等の高融点金属膜５３ｂを埋め込むことにより、第１ポリシリコン膜２８ｂ及び第２ポリシリコン膜３１ｂをショートさせている。
【０１３４】
このＦＬＡＳＨ ＥＰＲＯＭにおいては、前記周辺回路部の第２ゲート部３３ｃは、前記メモリセル部の第１ゲート部３３ａと同構造であるので、前記メモリセル部を形成する際に同時に前記周辺回路部を形成することができ、製造工程を簡単にすることができ効率的である。
なお、ここでは、第３導電体膜５３ａ又は５３ｂと、高融点金属膜（第４導電体膜）４２とをそれぞれ別々に形成しているが、共通の高融点金属膜として同時に形成してもよい。
【０１３５】
（実施例４）
−磁気ヘッドの製造−
実施例４は、本発明のレジストパターン厚肉化材料を用いた本発明のレジストパターンの応用例としての磁気ヘッドの製造に関する。なお、この実施例３では、以下のレジストパターン１０２及び１２６が、本発明のレジストパターン厚肉化材料を用いて実施例１及び２におけるのと同様の方法により厚肉化されたものである。
【０１３６】
図９（Ａ）〜（Ｄ）は、磁気ヘッドの製造を説明するための工程図である。
まず、図９（Ａ）に示すように、層間絶縁層１００上に、厚みが６μｍとなるようにレジスト膜を形成し、露光、現像を行って、渦巻状の薄膜磁気コイル形成用の開口パターンを有するレジストパターン１０２を形成した。
次に、図９（Ｂ）に示すように、層間絶縁層１００上における、レジストパターン１０２上及びレジストパターン１０２が形成されていない部位、即ち開口部１０４の露出面上に、厚みが０．０１μｍであるＴｉ密着膜と厚みが０．０５μｍであるＣｕ密着膜とが積層されてなるメッキ下地層１０６を蒸着法により形成した。
次に、図９（Ｃ）に示すように、層間絶縁層１００上における、レジストパターン１０２が形成されていない部位、即ち開口部１０４の露出面上に形成されたメッキ下地層１０６の表面に、厚みが３μｍであるＣｕメッキ膜からなる薄膜導体１０８を形成した。
次に、図９（Ｄ）に示すように、レジストパターン１０２を溶解除去し層間絶縁層１００上からリフトオフすると、薄膜導体１０８の渦巻状パターンによる薄膜磁気コイル１１０が形成される。
以上により磁気ヘッドを製造した。
【０１３７】
ここで得られた磁気ヘッドは、本発明の厚肉化材料を用いて厚肉化されたレジストパターン１０２により渦巻状パターンが微細に形成されているので、薄膜磁気コイル１１０は微細かつ精細であり、しかも量産性に優れる。
【０１３８】
図１０〜図１５は、他の磁気ヘッドの製造を説明するための工程図である。
図１０に示すように、セラミック製の非磁性基板１１２上にスパッタリング法によりギャップ層１１４を被覆形成した。なお、非磁性基板１１２上には、図示していないが予め酸化ケイ素による絶縁体層及びＮｉ−Ｆｅパーマロイからなる導電性下地層がスパッタリング法により被覆形成され、更にＮｉ−Ｆｅパーマロイからなる下部磁性層が形成されている。そして、図示しない前記下部磁性層の磁性先端部となる部分を除くギャップ層１１４上の所定領域に熱硬化樹脂により樹脂絶縁膜１１６を形成した。次に、樹脂絶縁膜１１６上にレジスト材を塗布してレジスト膜１１８を形成した。
【０１３９】
次に、図１１に示すように、レジスト膜１１８に露光、現像を行い、渦巻状パターンを形成した。そして、図１２に示すように、この渦巻状パターンのレジスト膜１１８を数百℃で一時間程度熱硬化処理を行い、突起状の第１渦巻状パターン１２０を形成した。更に、その表面にＣｕからなる導電性下地層１２２を被覆形成した。
【０１４０】
次に、図１３に示すように、導電性下地層１２２上にレジスト材をスピンコート法により塗布してレジスト膜１２４を形成した後、レジスト膜１２４を第１渦巻状パターン１２０上にパターニングしてレジストパターン１２６を形成した。
次に、図１４に示すように、導電性下地層１２２の露出面上に、即ちレジストパターン１２６が形成されていない部位上に、Ｃｕ導体層１２８をメッキ法により形成した。その後、図１５に示すように、レジストパターン１２６を溶解除去することにより、導電性下地層１２２上からリフトオフし、Ｃｕ導体層１２８による渦巻状の薄膜磁気コイル１３０を形成した。
以上により、図１６の平面図に示すような、樹脂絶縁膜１１６上に磁性層１３２を有し、表面に薄膜磁気コイル１３０が設けられた磁気ヘッドを製造した。
【０１４１】
ここで得られた磁気ヘッドは、本発明のレジストパターン厚肉化材料を用いて厚肉化されたレジストパターン１２６により渦巻状パターンが微細に形成されているので、薄膜磁気コイル１３０は微細かつ精細であり、しかも量産性に優れる。
【０１４２】
ここで、本発明の好ましい態様を付記すると、以下の通りである。
（付記１） 樹脂と架橋剤と含環状構造化合物とを含有することを特徴とするレジストパターン厚肉化材料。
（付記２） 水溶性乃至アルカリ可溶性である付記１に記載のレジストパターン厚肉化材料。
（付記３） 含環状構造化合物が、２５℃の水１００ｇ及び２．３８質量％テトラメチルアンモニウムハイドロオキサイド１００ｇのいずれかに対し１ｇ以上溶解する水溶性を示す付記１から２のいずれかに記載のレジストパターン厚肉化材料。
（付記４） 含環状構造化合物が極性基を２以上有する付記１から３のいずれかに記載のレジストパターン厚肉化材料。
（付記５） 極性基が、水酸基、アミノ基、スルホニル基、カルボニル基、カルボキシル基及びこれらの誘導基から選択される付記４に記載のレジストパターン厚肉化材料。
（付記６） 含環状構造化合物が、芳香族化合物、脂環族化合物及びヘテロ環状化合物から選択される少なくとも１種である付記１から５のいずれかに記載のレジストパターン厚肉化材料。
（付記７） 芳香族化合物が、ポリフェノール化合物、芳香族カルボン酸化合物、ナフタレン多価アルコール化合物、ベンゾフェノン化合物、フラボノイド化合物、これらの誘導体及びこれらの配糖体から選択され、
脂環族化合物が、ポリシクロアルカン、シクロアルカン、ステロイド類、これらの誘導体及びこれらの配糖体から選択され、
ヘテロ環状化合物が、ピロリジン、ピリジン、イミダゾール、オキサゾール、モルホリン、ピロリドン、フラン、ピラン、糖類及びこれらの誘導体から選択される付記６に記載のレジストパターン厚肉化材料。
（付記８） 樹脂が、環状構造を少なくとも一部に有してなる付記１から７のいずれかに記載のレジストパターン厚肉化材料。
（付記９） 環状構造を少なくとも一部に有してなる樹脂と架橋剤とを含有することを特徴とするレジストパターン厚肉化材料。
（付記１０） 環状構造が、芳香族化合物、脂環族化合物及びヘテロ環状化合物から選択される付記８から９のいずれかに記載のレジストパターン厚肉化材料。
（付記１１） 環状構造の樹脂におけるモル含有率が５ｍｏｌ％以上である付記８から１０のいずれかに記載のレジストパターン厚肉化材料。
（付記１２） 樹脂が、水溶性乃至アルカリ可溶性である付記１から１１のいずれかに記載のレジストパターン厚肉化材料。
（付記１３） 樹脂が、ポリビニルアルコール、ポリビニルアセタール及びポリビニルアセテートから選択される少なくとも１種である付記１から１２のいずれかに記載のレジストパターン厚肉化材料。
（付記１４） 樹脂が、ポリビニルアセタールを５〜４０質量％含有する付記１から１３のいずれかに記載のレジストパターン厚肉化材料。
（付記１５） 樹脂が、極性基を２以上有する付記１から１４のいずれかに記載のレジストパターン厚肉化材料。
（付記１６） 極性基が、水酸基、アミノ基、スルホニル基、カルボニル基、カルボキシル基及びこれらの誘導基から選択される付記１５に記載のレジストパターン厚肉化材料。
（付記１７） 架橋剤が、メラミン誘導体、ユリア誘導体及びウリル誘導体から選択される少なくとも１種である付記１から１６のいずれかに記載のレジストパターン厚肉化材料。
（付記１８） 界面活性剤を含む付記１から１７のいずれかに記載のレジストパターン厚肉化材料。
（付記１９） 界面活性剤が、非イオン性界面活性剤、カチオン性界面活性剤、アニオン性界面活性剤、及び両性界面活性剤から選択される少なくとも１種である付記１から１８のいずれかに記載のレジストパターン厚肉化材料。
（付記２０） 非イオン性界面活性剤が、ポリオキシエチレン−ポリオキシプロピレン縮合物化合物、ポリオキシアルキレンアルキルエーテル化合物、ポリオキシエチレンアルキルエーテル化合物、ポリオキシエチレン誘導体化合物、ソルビタン脂肪酸エステル化合物、グリセリン脂肪酸エステル化合物、第１級アルコールエトキシレート化合物、フェノールエトキシレート化合物、アルコキシレート系界面活性剤、脂肪酸エステル系界面活性剤、アミド系界面活性剤、アルコール系界面活性剤、及びエチレンジアミン系界面活性剤から選択され、
カチオン性界面活性剤が、アルキルカチオン系界面活性剤、アミド型４級カチオン系界面活性剤、及びエステル型４級カチオン系界面活性剤から選択され、
両性界面活性剤が、アミンオキサイド系界面活性剤、及びベタイン系界面活性剤から選択される付記１９に記載のレジストパターン厚肉化材料。
（付記２１） 有機溶剤を含む付記１から２０のいずれかに記載のレジストパターン厚肉化材料。
（付記２２） 有機溶剤が、アルコール系溶剤、鎖状エステル系溶剤、環状エステル系溶剤、ケトン系溶剤、鎖状エーテル系溶剤、及び環状エーテル系溶剤から選択される少なくとも1種である付記２１に記載のレジストパターン厚肉化材料。
（付記２３） レジストパターン上に表層を有してなり、同条件下における該表層のエッチング速度（Å／ｓ）と該レジストパターンのエッチング速度（Å／ｓ）との比（レジストパターン／表層）が１．１以上であることを特徴とするレジストパターン。
（付記２４） 表層が含環状構造化合物を含有してなる付記２３に記載のレジストパターン。
（付記２５） 含環状構造化合物の含有量が表層から内部に向かって漸次減少する付記２３から２４のいずれかに記載のレジストパターン。
（付記２６） レジストパターンを形成後、該レジストパターンの表面を覆うように付記１から２２のいずれかに記載のレジストパターン厚肉化材料を塗布してなる付記２３から２５のいずれかに記載のレジストパターン。
（付記２７） レジストパターンを形成後、該レジストパターンの表面を覆うように付記１から２２のいずれかに記載のレジストパターン厚肉化材料を塗布することを特徴とするレジストパターンの製造方法。
（付記２８） レジストパターン厚肉化材料の塗布後、該レジストパターン厚肉化材料の現像処理を行う付記２７に記載のレジストパターンの製造方法。
（付記２９） 現像処理が純水を用いて行われる付記２８に記載のレジストパターンの製造方法。
（付記３０） レジストパターン上に表層を有してなり、同条件下における該表層のエッチング速度（Å／ｓ）と該レジストパターンのエッチング速度（Å／ｓ）との比（レジストパターン／表層）が１．１以上である付記２７から２９のいずれかに記載のレジストパターンの製造方法。
（付記３１） 表層が含環状構造化合物及び環状構造の少なくともいずれかを含有してなる付記３０に記載のレジストパターン。
（付記３２） 含環状構造化合物及び環状構造の少なくともいずれかの含有量が表層から内部に向かって漸次減少する付記３０から３１のいずれかに記載のレジストパターン。
（付記３３） 付記２３から２６に記載のレジストパターンを用いて形成したパターンを少なくとも有してなることを特徴とする半導体装置。
（付記３４） 下地層上にレジストパターンを形成後、該レジストパターンの表面を覆うように付記１から２２のいずれかに記載のレジストパターン厚肉化材料を塗布することにより該レジストパターンを厚肉化するレジストパターン形成工程と、該厚肉化したレジストパターンをマスクとしてエッチングにより前記下地層をパターニングするパターニング工程とを含むことを特徴とする半導体装置の製造方法。
（付記３５） レジストパターンが、ＡｒＦレジストで形成された付記３４に記載の半導体装置の製造方法。
（付記３６） ＡｒＦレジストが、脂環族系官能基を側鎖に有するアクリル系レジスト、シクロオレフィン−マレイン酸無水物系レジスト及びシクロオレフィン系レジストから選択される少なくとも１種である付記３５に記載の半導体装置の製造方法。
（付記３７） レジストパターン形成工程の前に、レジストパターンの表面に、ポリオキシエチレン−ポリオキシプロピレン縮合物化合物、ポリオキシアルキレンアルキルエーテル化合物、ポリオキシエチレンアルキルエーテル化合物、ポリオキシエチレン誘導体化合物、ソルビタン脂肪酸エステル化合物、グリセリン脂肪酸エステル化合物、第１級アルコールエトキシレート化合物、及びフェノールエトキシレート化合物から選択される少なくとも１種である非イオン性界面活性剤を塗布する界面活性剤塗布工程を含む付記３４から３６のいずれかに記載の半導体装置の製造方法。
【０１４３】
【発明の効果】
本発明によると、前記要望に応え、従来における前記諸問題を解決することができる。
また、本発明によると、ＡｒＦレジスト等で形成されたレジストパターン上に塗布されて該レジストパターンを厚肉化し、既存の露光装置の光源における露光限界を超えて微細なレジスト抜けパターンを低コストで簡便に形成可能であり、かつ該レジストパターンのエッチング耐性を向上可能であるレジストパターン厚肉化材料を提供することができる。
また、本発明によると、ＡｒＦエキシマレーザー等を用いてパターニング可能であり、微細な構造を有し、エッチング耐性に優れたレジストパターンを提供することができる。
また、本発明によると、露光光（露光に用いる光）としてＡｒＦエキシマレーザー光を使用可能であり量産性に優れ、レジストパターンにより形成される微細パターンを光の露光限界を超えて精細に、かつ低コストで簡便に、しかもエッチング耐性を向上させて形成可能なレジストパターンの製造方法を提供することができる。
また、本発明によると、レジストパターンにより形成された微細パターンを有してなる高性能な半導体装置を提供することができる。
また、本発明によると、露光光（露光に用いる光）としてＡｒＦエキシマレーザー光を使用可能であり、微細パターンを有してなる高性能な半導体装置を効率的に量産可能な半導体装置の製造方法を提供することができる。
【図面の簡単な説明】
【図１】図１は、本発明のレジストパターン厚肉化材料を用いたレジストパターンの厚肉化のメカニズムを説明するための概略図である。
【図２】図２は、本発明のレジストパターンの製造方法の一例を説明するための概略図である。
【図３】図３は、本発明の半導体装置の一例であるＦＬＡＳＨ ＥＰＲＯＭを説明するための上面図である。
【図４】図４は、本発明の半導体装置の製造方法に関する一例であるＦＬＡＳＨ ＥＰＲＯＭの製造方法を説明するための断面概略図（その１）である。
【図５】図５は、本発明の半導体装置の製造方法に関する一例であるＦＬＡＳＨ ＥＰＲＯＭの製造方法を説明するための断面概略図（その２）である。
【図６】図６は、本発明の半導体装置の製造方法に関する一例であるＦＬＡＳＨ ＥＰＲＯＭの製造方法を説明するための断面概略図（その３）である。
【図７】図７は、本発明の半導体装置の製造方法に関する他の一例であるＦＬＡＳＨ ＥＰＲＯＭの製造方法を説明するための断面概略図である。
【図８】図８は、本発明の半導体装置の製造方法に関する他の一例であるＦＬＡＳＨ ＥＰＲＯＭの製造方法を説明するための断面概略図である。
【図９】図９は、本発明のレジストパターン厚肉化材料を用いて厚肉化したレジストパターンを磁気ヘッドの製造に応用した一例を説明するための断面概略図である。
【図１０】図１０は、本発明のレジストパターン厚肉化材料を用いて厚肉化したレジストパターンを磁気ヘッドの製造に応用した他の例の工程（その１）を説明するための断面概略図である。
【図１１】図１１は、本発明のレジストパターン厚肉化材料を用いて厚肉化したレジストパターンを磁気ヘッドの製造に応用した他の例の工程（その２）を説明するための断面概略図である。
【図１２】図１２は、本発明のレジストパターン厚肉化材料を用いて厚肉化したレジストパターンを磁気ヘッドの製造に応用した他の例の工程（その３）を説明するための断面概略図である。
【図１３】図１３は、本発明のレジストパターン厚肉化材料を用いて厚肉化したレジストパターンを磁気ヘッドの製造に応用した他の例の工程（その４）を説明するための断面概略図である。
【図１４】図１４は、本発明のレジストパターン厚肉化材料を用いて厚肉化したレジストパターンを磁気ヘッドの製造に応用した他の例の工程（その５）を説明するための断面概略図である。
【図１５】図１５は、本発明のレジストパターン厚肉化材料を用いて厚肉化したレジストパターンを磁気ヘッドの製造に応用した他の例の工程（その６）を説明するための断面概略図である。
【図１６】図１６は、図１０〜図１５の工程で製造された磁気ヘッドの一例を示す平面図である。
【符号の説明】
１ レジストパターン厚肉化材料
３ レジストパターン
５ 下地層（基材）
１０ レジストパターン（本発明）
１０ａ 表層
１０ｂ 内層レジストパターン
２２ Ｓｉ基板（半導体基板）
２３ フィールド酸化膜
２４ａ 第１ゲート絶縁膜
２４ｂ 第２ゲート絶縁膜
２５ａ 第１閾値制御層
２５ｂ 第２閾値制御層
２６ レジスト膜
２７ レジスト膜
２８ 第１ポリシリコン層（第１導電体膜）
２８ａ フローティングゲート電極
２８ｂ ゲート電極（第１ポリシリコン膜）
２８ｃ フローティングゲート電極
２９ レジスト膜
３０ａ キャパシタ絶縁膜
３０ｂ キャパシタ絶縁膜
３０ｃ キャパシタ絶縁膜
３０ｄ ＳｉＯ_２膜
３１ 第２ポリシリコン層（第２導電体膜）
３１ａ コントロールゲート電極
３１ｂ 第２ポリシリコン膜
３２ レジスト膜
３３ａ 第１ゲート部
３３ｂ 第２ゲート部
３３ｃ 第２ゲート部
３４ レジスト膜
３５ａ Ｓ／Ｄ（ソース・ドレイン）領域層
３５ｂ Ｓ／Ｄ（ソース・ドレイン）領域層
３６ａ Ｓ／Ｄ（ソース・ドレイン）領域層
３６ａ Ｓ／Ｄ（ソース・ドレイン）領域層
３７ 層間絶縁膜
３８ａ コンタクトホール
３８ｂ コンタクトホール
３９ａ コンタクトホール
３９ｂ コンタクトホール
４０ａ Ｓ／Ｄ（ソース・ドレイン）電極
４０ｂ Ｓ／Ｄ（ソース・ドレイン）電極
４１ａ Ｓ／Ｄ（ソース・ドレイン）電極
４１ｂ Ｓ／Ｄ（ソース・ドレイン）電極
４２ 高融点金属膜（第４導電体膜）
４２ａ 高融点金属膜（第４導電体膜）
４２ｂ 高融点金属膜（第４導電体膜）
４４ａ 第１ゲート部
４４ｂ 第２ゲート部
４５ａ Ｓ／Ｄ（ソース・ドレイン）領域層
４５ｂ Ｓ／Ｄ（ソース・ドレイン）領域層
４６ａ Ｓ／Ｄ（ソース・ドレイン）領域層
４６ｂ Ｓ／Ｄ（ソース・ドレイン）領域層
４７ 層間絶縁膜
４８ａ コンタクトホール
４８ｂ コンタクトホール
４９ａ コンタクトホール
４９ｂ コンタクトホール
５０ａ Ｓ／Ｄ（ソース・ドレイン）電極
５０ｂ Ｓ／Ｄ（ソース・ドレイン）電極
５１ａ Ｓ／Ｄ（ソース・ドレイン）電極
５１ｂ Ｓ／Ｄ（ソース・ドレイン）電極
５２ａ 開口部
５２ｂ 開口部
５３ａ 高融点金属膜（第３導電体膜）
５３ｂ 高融点金属膜（第３導電体膜）
５４ 絶縁膜
１００ 層間絶縁層
１０２ レジストパターン
１０４ 開口部
１０６ メッキ下地層
１０８ 薄膜導体（Ｃｕメッキ膜）
１１０ 薄膜磁気コイル
１１２ 非磁性基板
１１４ ギャップ層
１１６ 樹脂絶縁層
１１８ レジスト膜
１１８ａ レジストパターン
１２０ 第１渦巻状パターン
１２２ 導電性下地層
１２４ レジスト膜
１２６ レジストパターン
１２８ Ｃｕ導体膜
１３０ 薄膜磁気コイル
１３２ 磁性層[0001]
BACKGROUND OF THE INVENTION
The present invention is applied on a resist pattern formed of an ArF resist or the like to thicken the resist pattern, and can form a fine resist omission pattern exceeding the exposure limit in the light source of an existing exposure apparatus, and A resist pattern that can improve the etching resistance of the resist pattern, a resist pattern that can be patterned using a thickening material, an ArF excimer laser, etc., has a fine structure, has excellent etching resistance, and its efficient production The present invention relates to a method, a semiconductor device having a fine pattern formed by the resist pattern, and an efficient manufacturing method.
[0002]
[Prior art]
Currently, high integration of semiconductor integrated circuits is progressing, and LSI and VLSI have been put into practical use, and accordingly, the wiring pattern extends to an area of 0.2 μm or less and the minimum pattern reaches 0.1 μm or less. To form a fine wiring pattern, a substrate to be processed on which a thin film is formed is covered with a resist film, subjected to selective exposure and developed to form a resist pattern, and then dry etching is performed using the resist pattern as a mask. A lithography technique that obtains a desired pattern by removing the resist pattern is very important.
The formation of a fine wiring pattern requires both the shortening of the wavelength of the light source in the exposure apparatus and the development of a resist material having a high resolution according to the characteristics of the light source. However, in order to reduce the wavelength of the light source in the exposure apparatus, it is necessary to update the exposure apparatus that requires enormous costs. On the other hand, it is not easy to develop a resist material to cope with exposure using a short wavelength light source.
[0003]
In the manufacturing process of a semiconductor device, a fine resist removal pattern is formed by a resist pattern, and then fine patterning is performed using the resist pattern as a mask. Therefore, the resist pattern has excellent etching resistance. It is desirable. However, the ArF (argon fluoride) excimer laser exposure technology, which is the latest technology, has a problem that the etching resistance of the resist material used is not sufficient. Therefore, it is conceivable to use a KrF (krypton fluoride) resist having excellent etching resistance. However, when the etching conditions are severe, the layer to be processed is thick, the fine pattern is formed, or the resist is thin. There is a possibility that the etching resistance may be insufficient, and it is desired to develop a technique capable of forming a resist pattern excellent in etching resistance and forming a fine resist omission pattern by the resist pattern.
[0004]
It should be noted that, by using KrF (krypton fluoride) excimer laser light (wavelength 248 nm), which is the deep ultraviolet ray, as the exposure light for the resist, a resist removal pattern refinement technique called RELACS that can form a fine removal pattern Has been proposed (see, for example, Patent Document 1). This technique uses a KrF (krypton fluoride) excimer laser (wavelength 248 nm) as the exposure light to form a resist pattern by exposing the resist (positive type or negative type), and then forms a water-soluble resin composition. A coating film is provided so as to cover the resist pattern, and the coating film and the resist pattern are allowed to interact with each other using the residual acid in the resist pattern material at the interface to thicken the resist pattern. (Hereinafter sometimes referred to as “swelling”), the distance between the resist patterns is shortened to form a fine resist omission pattern.
[0005]
However, in this case, the KrF (krypton fluoride) resist used is an aromatic resin composition such as a novolak resin or naphthoquinone diazide, and the aromatic ring contained in the aromatic resin composition is the ArF excimer laser beam. Therefore, the ArF (argon fluoride) excimer laser beam cannot pass through the KrF (krypton fluoride) resist, and the ArF (argon fluoride) excimer laser beam is used as the exposure light. There is a problem that can not be.
From the viewpoint of forming a fine wiring pattern, it is desirable that ArF (argon fluoride) excimer laser light having a shorter wavelength than KrF (krypton fluoride) excimer laser light can be used as a light source in the exposure apparatus. It is.
[0006]
Therefore, ArF (Argon Fluoride) excimer laser light can also be used as a light source for the exposure apparatus during patterning, and a technique that can easily form a fine pattern of resist removal with excellent etching resistance at low cost has not yet been provided. There is no current situation.
[0007]
[Patent Document 1]
Japanese Patent Laid-Open No. 10-73927
[0008]
[Problems to be solved by the invention]
The present invention has been made in response to such a demand, and solves the above-described problems and achieves the following objects. That is, the present invention is applied on a resist pattern formed of an ArF resist or the like to thicken the resist pattern, and a fine resist omission pattern exceeding the exposure limit of a light source of an existing exposure apparatus can be easily obtained at low cost. It is an object of the present invention to provide a resist pattern thickening material that can be formed in a uniform manner and that can improve the etching resistance of the resist pattern.
It is another object of the present invention to provide a resist pattern that can be patterned using an ArF excimer laser or the like, has a fine structure, and has excellent etching resistance.
In addition, the present invention can use ArF excimer laser light as exposure light (light used for exposure), is excellent in mass productivity, and has a fine pattern formed by a resist pattern exceeding the light exposure limit. An object of the present invention is to provide a method for producing a resist pattern which can be formed easily at a low cost and with improved etching resistance.
Another object of the present invention is to provide a high-performance semiconductor device having a fine pattern formed by a resist pattern.
The present invention also provides a method of manufacturing a semiconductor device that can use ArF excimer laser light as exposure light (light used for exposure) and can efficiently mass-produce high-performance semiconductor devices having fine patterns. The purpose is to provide.
[0009]
[Means for Solving the Problems]
  Means for solving the above-described problems are as described in (Appendix 1) to (Appendix 37) described later.
  The resist pattern thickening material of the present invention isWater-soluble or alkali-soluble resinAnd a crosslinking agent and at least one cyclic structure compound selected from catechin, delphinidin, resorcin, 1,3-naphthalenediol, and 4-hydroxyadamantane-2-carboxylic acid, orPolyvinyl acetal resin having a polyphenol structure, acetalized by 5 mol% or more with an aldehyde having a polyphenol structureAnd a crosslinking agent. When the resist pattern thickening material is applied onto the resist pattern, among the applied resist pattern thickening material, those near the interface with the resist pattern soak into the resist pattern and crosslink ( Mixing). At this time, since the affinity between the resist pattern thickening material and the resist pattern is good, the resist pattern thickening material and the resist pattern are integrated (mixed) on the surface of the resist pattern. Thus, the surface layer (mixing layer) is efficiently formed (the resist pattern is efficiently thickened by the resist pattern thickening material). The surface layer is formed of the resist pattern thickening material and contains a cyclic structure compound or a resin having at least a part of the cyclic structure, and therefore has excellent etching resistance. Since the resist pattern thus formed (hereinafter sometimes referred to as “thickened resist pattern”) is thickened by the resist pattern thickening material, the omission formed by the thickened resist pattern. The pattern has a finer structure beyond the exposure limit.
[0010]
The resist pattern of the present invention has a surface layer on the resist pattern, and the ratio between the etching rate (Å / s) of the surface layer and the etching rate (Å / s) of the resist pattern under the same conditions (resist pattern / Surface layer) is 1.1 or more. The resist pattern can be formed by using an ArF excimer laser as exposure light and has a surface layer excellent in etching resistance. Therefore, the resist pattern can be etched and is suitable for forming a fine pattern.
[0011]
The resist pattern manufacturing method of the present invention is characterized in that after forming a resist pattern, the resist pattern thickening material of the present invention is applied so as to cover the surface of the resist pattern. In the method for forming a resist pattern of the present invention, when the resist pattern thickening material is applied onto the formed resist pattern, the interface with the resist pattern among the applied resist pattern thickening material. What is nearby soaks into the resist pattern and crosslinks (mixes). Therefore, on the surface of the resist pattern, the resist pattern thickening material and the resist pattern are integrated (a mixing layer is formed), and the resist pattern is thickened. The surface layer is formed of the resist pattern thickening material and contains a cyclic structure compound or a resin having at least a part of the cyclic structure, and therefore has excellent etching resistance. Since the thickened resist pattern formed in this way is thickened by the resist pattern thickening material, the resist omission pattern formed by the resist pattern has a finer structure beyond the exposure limit. .
[0012]
The semiconductor device of the present invention is characterized by having at least a pattern formed by the resist pattern of the present invention. Since the semiconductor device of the present invention has a fine pattern formed by the resist pattern, it has high quality and high performance.
[0013]
In the method for manufacturing a semiconductor device of the present invention, after forming a resist pattern on an underlayer, the resist pattern is thickened by applying the resist pattern thickening material of the present invention so as to cover the surface of the resist pattern. And a patterning step of patterning the underlayer by etching using the thickened resist pattern as a mask. In the method for manufacturing a semiconductor device of the present invention, after a resist pattern is formed on the underlayer, the resist pattern thickening material is applied onto the resist pattern. Then, the resist pattern thickening material in the vicinity of the interface with the resist pattern soaks into the resist pattern and crosslinks with the resist pattern material. For this reason, a surface layer (mixing layer) integrated with the resist pattern is formed on the resist pattern. The surface layer is formed of the resist pattern thickening material and contains a cyclic structure compound or a resin having a cyclic structure in at least a part thereof. It can be suitably performed. Since the obtained resist pattern is thickened by the resist pattern thickening material, the width of the pattern by the thickened resist pattern is larger than the pattern width by the resist pattern before thickening. The resist pattern is thickened by the thickness of the resist pattern thickening material (it is miniaturized), and the pattern formed by the resist pattern is formed more finely beyond the light exposure limit. The Then, the underlying layer is finely patterned by performing etching using the finely formed pattern having excellent etching resistance as a mask. As a result, a high-performance semiconductor device having an extremely fine pattern is efficiently manufactured.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
(Resist pattern thickening material)
The resist pattern thickening material of the present invention is a water-soluble or alkali-soluble composition, and is usually an aqueous solution, but may be a colloidal liquid, an emulsion liquid, or the like.
As the resist pattern thickening material of the present invention, the first form and the second form are preferable.
The resist pattern thickening material according to the first embodiment comprises a resin, a crosslinking agent, and a cyclic structure-containing compound, and further contains a surfactant, an organic solvent, and other components as necessary. It becomes. The resin may be a resin having a ring structure in part.
The resist pattern thickening material according to the second embodiment contains a resin having a cyclic structure in part and a cross-linking agent, and if necessary, the resin and the cyclic structure compound , Containing the nonionic surfactant, the organic solvent, and the other components.
[0015]
-Resin-
The resin is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably water-soluble (resin) or alkali-soluble (resin) and can cause a crosslinking reaction, or a crosslinking agent. More preferably, they can be mixed.
The said resin may be used individually by 1 type, and may use 2 or more types together.
[0016]
When the resin is a water-soluble resin, the water-soluble resin preferably has a water solubility of 0.1 g or more in water at 25 ° C., and more preferably has a water solubility of 0.3 g or more. A water-soluble one that dissolves 0.5 g or more is particularly preferable.
Examples of the water-soluble resin include polyvinyl alcohol, polyvinyl acetal, polyvinyl acetate, polyacrylic acid, polyvinyl pyrrolidone, polyethyleneimine, polyethylene oxide, styrene-maleic acid copolymer, polyvinylamine, polyallylamine, and an oxazoline group-containing water-soluble resin. Examples thereof include resins, water-soluble melamine resins, water-soluble urea resins, alkyd resins, and sulfonamide resins.
[0017]
When the resin is an alkali-soluble resin, the alkali-soluble resin is preferably an alkali-soluble resin that dissolves 0.1 g or more in a 2.38% tetramethylammonium hydroxide (TMAH) aqueous solution at 25 ° C., What shows the alkali solubility which melt | dissolves 0.3g or more is more preferable, and the thing which shows the alkali solubility which melt | dissolves 0.5g or more is especially preferable.
Examples of the alkali-soluble resin include novolak resins, vinylphenol resins, polyacrylic acid, polymethacrylic acid, poly p-hydroxyphenyl acrylate, poly p-hydroxyphenyl methacrylate, and copolymers thereof.
[0018]
Among these resins, polyvinyl alcohol, polyvinyl acetal, polyvinyl acetate and the like are preferable, more preferably polyvinyl acetal is contained, and the polyvinyl acetal is 5 to 40 in that the solubility can be easily changed by crosslinking. More preferably, it is contained by mass%.
[0019]
  In the present invention, in the case of the resist pattern thickening material according to the first embodiment, the resin may be a resin having an annular structure at least in part, and the resist pattern according to the second embodiment In the case of a thickening material, it contains a resin having at least a part of the cyclic structure as an essential component, and may further contain the resin.
[0020]
Examples of the aromatic compounds include polyhydric phenol compounds, polyphenol compounds, aromatic carboxylic acid compounds, naphthalene polyhydric alcohol compounds, benzophenone compounds, flavonoid compounds, porphine, water-soluble phenoxy resins, aromatic-containing water-soluble dyes, and the like. Derivatives thereof, glycosides thereof, and the like. These may be used alone or in combination of two or more.
[0021]
Examples of the polyhydric phenol compound include resorcin, resorcin [4] arene, pyrogallol, gallic acid, derivatives or glycosides thereof, and the like.
[0022]
Examples of the polyphenol compound and derivatives thereof include catechin, anthocyanidin (pelargosine type (4′-hydroxy), cyanidin type (3 ′, 4′-dihydroxy), delphinidin type (3 ′, 4 ′, 5′-trihydroxy). )), Flavan-3,4-diol, proanthocyanidins, derivatives or glycosides thereof, and the like.
[0023]
Examples of the aromatic carboxylic acid compound and derivatives thereof include salicylic acid, phthalic acid, dihydroxybenzoic acid, tannin, derivatives and glycosides thereof, and the like.
[0024]
Examples of the naphthalene polyhydric alcohol compound and derivatives thereof include naphthalenediol, naphthalenetriol, derivatives or glycosides thereof, and the like.
[0025]
Examples of the benzophenone compound and derivatives thereof include alizarin yellow A, derivatives or glycosides thereof, and the like.
[0026]
Examples of the flavonoid compound and derivatives thereof include flavone, isoflavone, flavanol, flavonone, flavonol, flavan-3-ol, aurone, chalcone, dihydrochalcone, quercetin, derivatives or glycosides thereof, and the like.
[0027]
Examples of the alicyclic compound include polycycloalkanes, cycloalkanes, condensed rings, derivatives thereof, glycosides thereof, and the like. These may be used individually by 1 type and may use 2 or more types together.
Examples of the polycycloalkanes include norbornane, adamantane, norpinane, and sterane.
Examples of the cycloalkanes include cyclopentane and cyclohexane.
Examples of the condensed ring include steroids.
[0028]
Examples of the heterocyclic compound include nitrogen-containing cyclic compounds such as pyrrolidine, pyridine, imidazole, oxazole, morpholine, and pyrrolidone, oxygen-containing cyclic compounds such as polysaccharides including furan, pyran, pentose, and hexose. Etc. are preferable.
[0029]
Among the resins having at least a part of the resin and the cyclic structure, those having two or more polar groups are preferable in that they are excellent in at least one of water solubility and alkali solubility.
The polar group is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include a hydroxyl group, a cyano group, an alkoxyl group, a carboxyl group, a carbonyl group, an amino group, an amide group, an alkoxycarbonyl group, and a hydroxy group. Examples include alkyl groups, sulfonyl groups, acid anhydride groups, lactone groups, cyanate groups, isocyanate groups, and ketone groups. Among these polar groups, a hydroxyl group, an amino group, a carboxyl group, a carbonyl group, an amino group, and a sulfonyl group are preferable.
[0030]
Further, when the resin is a resin having at least a part of the cyclic structure, the resin portion other than the cyclic structure is not particularly limited as long as the entire resin is water-soluble or alkaline, and is appropriately selected according to the purpose. Suitable examples include water-soluble resins such as polyvinyl alcohol and polyvinyl acetal described above, and alkali-soluble resins such as novolac resins and vinyl phenol resins.
[0031]
Further, when the resin is a resin having at least a part of the cyclic structure, the molar content of the cyclic structure is not particularly limited and can be appropriately selected according to the purpose, but has high etching resistance. Is required, it is preferably 5 mol% or more, more preferably 10 mol% or more.
In addition, the said molar content rate can be measured using NMR etc., for example.
[0032]
The content of the resin in the resist pattern thickening material differs depending on the type, content, etc. of the cross-linking agent, the cyclic structure-containing compound, the surfactant, etc. It can be determined accordingly.
[0033]
-Crosslinking agent-
The cross-linking agent is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably water-soluble or alkali-soluble, and preferably generates a cross-linking reaction by heat or acid. Amino crosslinking agents are preferred.
[0034]
Suitable examples of the amino crosslinking agent include urea derivatives, melamine derivatives, uril derivatives, and the like. These may be used individually by 1 type and may use 2 or more types together.
Examples of the urea derivative include urea, alkoxymethylene urea, N-alkoxymethylene urea, ethylene urea, ethylene urea carboxylic acid, and derivatives thereof.
Examples of the melamine derivative include alkoxymethylmelamine and derivatives thereof.
Examples of the uril derivative include benzoguanamine, glycoluril, and derivatives thereof.
[0035]
As content in the resist pattern thickening material of the crosslinking agent, depending on the type, content, etc. of the resin, the resin containing the cyclic structure compound or the cyclic structure in part, the surfactant, etc. Although it is different and cannot be specified unconditionally, it can be appropriately determined according to the purpose.
[0036]
-Cyclic structure compound-
The cyclic structure-containing compound is not particularly limited as long as it contains the cyclic structure, and can be appropriately selected according to the purpose, and may be a compound, a resin, It is preferably alkali-soluble.
Since the resist pattern thickening material of the present invention contains the cyclic structure compound, the etching resistance of the thickened resist pattern can be remarkably improved as compared with that before thickening.
[0037]
In the case where the cyclic structure-containing compound is water-soluble, as the water-solubility, for example, a water-soluble one that dissolves 0.1 g or more in 100 g of water at 25 ° C. is preferable, and water-solubility that dissolves 0.3 g or more. Are more preferable, and those exhibiting water solubility capable of dissolving 0.5 g or more are particularly preferable.
When the cyclic structure compound is alkali-soluble, the alkali-solubility is, for example, an alkali-soluble compound that dissolves 0.1 g or more in a 2.38% tetramethylammonium hydroxide (TMAH) aqueous solution at 25 ° C. More preferably, 0.3 g or more soluble alkali soluble is more preferable, 0.5 g or more soluble alkali soluble is particularly preferable.
[0038]
Preferred examples of the cyclic structure compound include the aromatic compound, the alicyclic compound, and the heterocyclic compound. Specific examples of these are as described above.
[0039]
Among the cyclic structure-containing compounds, those having two or more polar groups are preferable, those having three or more are more preferable, and those having four or more are particularly preferable in that they are excellent in at least one of water solubility and alkali solubility.
The polar group is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include a hydroxyl group, a cyano group, an alkoxyl group, a carboxyl group, a carbonyl group, an amino group, an amide group, an alkoxycarbonyl group, and a hydroxy group. Examples include alkyl groups, sulfonyl groups, acid anhydride groups, lactone groups, cyanate groups, isocyanate groups, and ketone groups. Among these polar groups, a hydroxyl group, an amino group, a carboxyl group, a carbonyl group, an amino group, and a sulfonyl group are preferable.
[0040]
When the cyclic structure compound is a resin, the molar content of the cyclic structure with respect to the resin is not particularly limited and can be appropriately selected according to the purpose, but when high etching resistance is required. Is preferably 5 mol% or more, more preferably 10 mol% or more.
In addition, the said molar content rate can be measured using NMR etc., for example.
[0041]
The content of the cyclic structure compound in the resist pattern thickening material can be appropriately determined according to the type and content of the resin, the crosslinking agent, the surfactant, and the like.
[0042]
-Surfactant-
The surfactant can be suitably used when the affinity between the resist pattern thickening material and the resist pattern (for example, ArF resist) to which the resist pattern thickening material is applied is not sufficient, When the surfactant is contained in the resist pattern thickening material, the resist pattern can be thickened efficiently and with excellent in-plane uniformity, and a fine pattern with excellent etching resistance can be obtained. It can form uniformly and efficiently, and can suppress effectively that this resist pattern thickening material foams.
[0043]
The surfactant is not particularly limited and may be appropriately selected depending on the intended purpose. However, nonionic surfactants, cationic surfactants, anionic surfactants, amphoteric surfactants, silicone-based surfactants Surfactant etc. are mentioned. These may be used individually by 1 type and may use 2 or more types together. Among these, nonionic surfactants are preferable in that they do not contain metal ions.
[0044]
The nonionic surfactant is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include alkoxylate surfactants, fatty acid ester surfactants, amide surfactants, alcohols Preferred are those selected from surfactants and ethylenediamine surfactants. Specific examples of these include polyoxyethylene-polyoxypropylene condensate compounds, polyoxyalkylene alkyl ether compounds, polyoxyethylene alkyl ether compounds, polyoxyethylene derivative compounds, sorbitan fatty acid ester compounds, glycerin fatty acid ester compounds, Primary alcohol ethoxylate compound, phenol ethoxylate compound, nonylphenol ethoxylate, octylphenol ethoxylate, lauryl alcohol ethoxylate, oleyl alcohol ethoxylate, fatty acid ester, amide, natural alcohol, ethylenediamine, Secondary alcohol ethoxylate type and the like.
[0045]
The cationic surfactant is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include an alkyl cationic surfactant, an amide quaternary cationic surfactant, and an ester quaternary cationic surfactant. Surfactant etc. are mentioned.
[0046]
There is no restriction | limiting in particular as said amphoteric surfactant, According to the objective, it can select suitably, For example, an amine oxide type surfactant, a betaine type surfactant, etc. are mentioned.
[0047]
The content of the surfactant in the resist pattern thickening material differs depending on the type and content of the resin, the cross-linking agent, the cyclic structure compound, etc., and cannot be specified unconditionally. Can be appropriately selected according to the purpose.
[0048]
-Organic solvent-
The organic solvent is contained in the resist pattern thickening material, thereby partially including the resin, the cross-linking agent, the cyclic structure compound, and the cyclic structure in the resist pattern thickening material. The solubility of the resin or the like can be improved.
[0049]
The organic solvent is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include alcohol-based organic solvents, chain ester-based organic solvents, cyclic ester-based organic solvents, ketone-based organic solvents, and chain ethers. And organic ether solvents and cyclic ether organic solvents.
[0050]
Examples of the alcohol organic solvent include methanol, ethanol, propyl alcohol, isopropyl alcohol, butyl alcohol, and the like.
Examples of the chain ester organic solvent include ethyl lactate and propylene glycol methyl ether acetate (PGMEA).
Examples of the cyclic ester organic solvent include lactone organic solvents such as γ-butyrolactone.
Examples of the ketone organic solvent include ketone organic solvents such as acetone, cyclohexanone, and heptanone.
Examples of the chain ether organic solvent include ethylene glycol dimethyl ether.
Examples of the cyclic ether include tetrahydrofuran, dioxane, and the like.
[0051]
These organic solvents may be used individually by 1 type, and may use 2 or more types together. Among these, the thing which has a boiling point of about 80-200 degreeC is preferable at the point which can thicken finely.
[0052]
The content of the organic solvent in the resist pattern thickening material can be appropriately determined according to the type and content of the resin, the cyclic structure-containing compound, the crosslinking agent, the surfactant, and the like. .
[0053]
-Other ingredients-
The other components are not particularly limited as long as they do not impair the effects of the present invention, and can be appropriately selected according to the purpose. Various known additives such as thermal acid generators, amines, amides, A quencher represented by ammonium chlorine and the like is preferable.
The content of the other components in the resist pattern thickening material may be appropriately determined according to the type and content of the resin, the cyclic structure-containing compound, the crosslinking agent, the surfactant, and the like. it can.
[0054]
-Use etc.-
The resist pattern thickening material of the present invention can be used by coating on the resist pattern.
In addition, at the time of the application, the surfactant may not be contained in the resist pattern thickening material but may be separately applied before applying the resist pattern thickening material.
[0055]
When the resist pattern thickening material is applied onto the resist pattern, the resist pattern is thickened to form a thickened resist pattern.
The diameter or width (opening dimension) of the resist removal pattern formed by the thickened resist pattern thus obtained is smaller than the diameter or width of the resist removal pattern formed by the resist pattern. A finer resist omission pattern is formed beyond the exposure limit of the light source of the exposure apparatus used when patterning the resist pattern. For example, when ArF excimer laser light is used when patterning the resist pattern, the resulting resist pattern is thickened using the resist pattern thickening material of the present invention to form a thickened resist pattern. Then, the resist omission pattern formed by the thickened resist pattern provides a fine resist omission pattern similar to that obtained when patterning using an electron beam.
At this time, the thickness of the resist pattern can be controlled within a desired range by appropriately adjusting the viscosity, coating thickness, baking temperature, baking time, and the like of the resist pattern thickening material. .
[0056]
-Resist pattern material-
The material of the resist pattern (the resist pattern to which the resist pattern thickening material of the present invention is applied) is not particularly limited and can be appropriately selected from known resist materials according to the purpose. For example, g-line resist, i-line resist, KrF resist, ArF that can be patterned with g-line, i-line, KrF excimer laser, ArF excimer laser, F2 excimer laser, electron beam, etc. A resist, an F2 resist, an electron beam resist and the like are preferable. These may be chemically amplified or non-chemically amplified. Among these, KrF resist, ArF resist, etc. are preferable, and ArF resist is more preferable.
Specific examples of the resist pattern material include novolak resist, PHS resist, acrylic resist, cycloolefin-maleic anhydride (COMA) resist, cycloolefin resist, and hybrid (alicyclic acrylic). -COMA copolymer) resist and the like. These may be modified with fluorine.
[0057]
The resist pattern forming method, size, thickness, and the like are not particularly limited and can be appropriately selected according to the purpose. In particular, the thickness is appropriately determined depending on the substrate to be processed, etching conditions, and the like. However, it is generally about 0.2 to 200 μm.
[0058]
The thickening of the resist pattern using the resist pattern thickening material of the present invention will be described below with reference to the drawings.
As shown in FIG. 1A, after forming a resist pattern 3 on an underlayer (base material) 5, a resist pattern thickening material 1 is applied to the surface of the resist pattern 3 and prebaked (heated and dried). ) To form a coating film. Then, as shown in FIG. 1B, the resist pattern thickening material 1 is mixed (impregnated) into the resist pattern 3 in the vicinity of the interface between the resist pattern 3 and the resist pattern thickening material 1, and further mixing is performed. The (impregnated) portion is crosslinked, and a mixing layer is formed by the resist pattern 3 and the resist pattern thickening material 1. At this time, as shown in FIG. 1B, the resist pattern has a surface layer 10a as the mixing layer on the inner layer resist pattern 10b (resist pattern 3).
Thereafter, as shown in FIG. 1 (c), by performing development processing, a portion of the applied resist pattern thickening material 1 that is not mixed with the resist pattern 3 is dissolved and removed, and the thickness is increased. A thickened resist pattern 10 is formed (developed).
The development treatment may be water development or development with an alkaline developer.
[0059]
The thickened resist pattern 10 has a surface layer 10a formed by mixing (impregnating) and crosslinking the resist pattern thickening material 1 on the surface of the resist pattern 10b (resist pattern 3). Since the thickened resist pattern 10 is thicker than the resist pattern 3 by the thickness of the surface layer 10a, the width of the resist removal pattern formed by the thickened resist pattern 10 is formed by the resist pattern 3. It is smaller than the width of the resist omission pattern. For this reason, the resist omission pattern can be finely formed exceeding the exposure limit of the light source in the exposure apparatus when forming the resist pattern 3, and the resist omission pattern formed by the thickened resist pattern 10 is the resist pattern. 3 is finer than the resist omission pattern formed by 3.
[0060]
The surface layer 10a in the thickened resist pattern 10 is formed by the resist pattern thickening material 1 containing at least one of the cyclic structure compound and the resin having the cyclic structure in part. Excellent resistance. For this reason, even if the resist pattern 3 is formed of a material having inferior etching resistance, the resulting thickened resist pattern 10 has the surface layer 10a having excellent etching resistance. It will be a thing.
[0061]
-Application-
The resist pattern thickening material of the present invention can be suitably used to thicken a resist pattern and to refine a resist omission pattern beyond the exposure limit. In addition, the resist pattern thickening material of the present invention can be particularly suitably used for the resist pattern of the present invention and its manufacturing method, and the semiconductor device and its manufacturing method.
Further, since the resist pattern thickening material of the present invention contains at least one of the cyclic structure compound and the resin partially having the cyclic structure, it is exposed to plasma or the like and etched on the surface. It can also be suitably used for coating or thickening a pattern formed of a resin or the like that needs to have improved resistance, and has a part of the cyclic structure compound and the cyclic structure as a material of the pattern. When at least one of the formed resins cannot be used, it can be used more suitably.
[0062]
(Resist pattern)
The resist pattern of the present invention has a surface layer on the resist pattern.
The surface layer preferably has excellent etching resistance, and preferably has a lower etching rate (） / s) than the resist pattern. Specifically, the ratio (resist pattern / surface layer) between the etching rate (Å / s) of the surface layer and the etching rate (Å / s) of the resist pattern when measured under the same conditions is 1.1. Preferably, it is 1.2 or more, more preferably 1.3 or more.
The etching rate (Å / s) is measured, for example, by performing a predetermined time etching process using a known etching apparatus, measuring the film thickness of the sample, and calculating the film thickness per unit time. be able to.
[0063]
The surface layer preferably contains at least one of the cyclic structure compound and a resin having a cyclic structure in part, and is preferably formed using the resist pattern thickening material of the present invention. it can.
Whether or not the surface layer contains at least one of the cyclic structure compound and a resin having a cyclic structure in part can be confirmed, for example, by analyzing an IR absorption spectrum of the surface layer. it can.
[0064]
The resist pattern may contain at least one of a cyclic structure compound and a resin having a cyclic structure in part, and this aspect is also preferable from the viewpoint of the groundworkability.
[0065]
In the resist pattern of the present invention, the boundary between the resist pattern and the surface layer may be a clear structure or an unclear structure. In the case of the former structure, in general, the content of at least one of the cyclic structure compound and the resin partially having the cyclic structure decreases discontinuously from the surface layer toward the inside, and in the case of the latter structure In general, the content of at least one of the cyclic structure compound and the resin having a cyclic structure in a part gradually decreases from the surface layer toward the inside.
[0066]
The resist pattern of the present invention can be preferably produced by the method for producing a resist pattern of the present invention described below.
The resist pattern of the present invention is used for connecting functional parts such as mask patterns, reticle patterns, magnetic heads, LCDs (liquid crystal displays), PDPs (plasma display panels), SAW filters (surface acoustic wave filters), and optical wiring, for example. The present invention can be suitably used for optical parts, microparts such as microactuators, semiconductor devices, and the like, and can be suitably used for the semiconductor device of the present invention and its manufacturing method described later.
[0067]
(Resist pattern manufacturing method)
In the method for producing a resist pattern of the present invention, after forming the resist pattern, the resist pattern thickening material of the present invention is applied so as to cover the surface of the resist pattern.
[0068]
As the material of the resist pattern, those described above in the description of the resist pattern thickening material of the present invention are preferably mentioned, and an ArF resist is particularly preferable.
The resist pattern can be formed according to a known method.
The resist pattern can be formed on a base (base material), and the base (base material) is not particularly limited and may be appropriately selected depending on the intended purpose. In the case of forming the substrate, generally, the substrate (base material) preferably includes a substrate such as a silicon wafer, various oxide films, and the like.
[0069]
The method for applying the resist pattern thickening material is not particularly limited, and can be appropriately selected from known application methods according to the purpose. For example, a spin coating method is preferably used. In the case of the spin coating method, for example, the rotational speed is about 100 to 10000 rpm, preferably 800 to 5000 rpm, the time is about 1 to 10 minutes, and preferably 1 to 90 seconds.
The coating thickness at the time of coating is usually about 100 to 10,000 mm, and preferably about 2000 to 5000 mm.
In addition, at the time of the application, the surfactant may not be contained in the resist pattern thickening material but may be separately applied before applying the resist pattern thickening material.
[0070]
Pre-baking (heating and drying) the applied resist pattern thickening material during or after the application is performed at the interface between the resist pattern and the resist pattern thickening material. This is preferable in that mixing (impregnation) of the material into the resist pattern can be efficiently generated.
The pre-baking (heating / drying) conditions and method are not particularly limited as long as the resist pattern is not softened, and can be appropriately selected according to the purpose. For example, the temperature is 40 to 120 ° C. 70 to 100 ° C is preferable, the time is about 10 seconds to 5 minutes, and 40 seconds to 100 seconds is preferable.
[0071]
In addition, baking the applied resist pattern thickening material after the pre-baking (heating / drying) effectively performs the mixing at the interface between the resist pattern and the resist pattern thickening material. This is preferable in that it can be advanced.
The baking conditions and method are not particularly limited and may be appropriately selected depending on the intended purpose. However, usually higher temperature conditions than the pre-baking (heating / drying) are employed. As conditions for the baking, for example, the temperature is about 70 to 150 ° C., preferably 90 to 130 ° C., the time is about 10 seconds to 5 minutes, and preferably 40 seconds to 100 seconds.
[0072]
Furthermore, it is preferable that after the baking, the applied resist pattern thickening material is developed. In this case, it is preferable in that the thickened resist pattern can be developed (obtained) by dissolving and removing a portion of the applied resist pattern thickening material that is not mixed with the resist pattern.
The development processing is as described above.
[0073]
Here, the method for producing a resist pattern of the present invention will be described below with reference to the drawings.
As shown in FIG. 2 (a), after applying a resist material 3a on the base layer (base material) 5, after patterning this to form a resist pattern 3 as shown in FIG. 2 (b), As shown in FIG. 2C, the resist pattern thickening material 1 is applied to the surface of the resist pattern 3 and prebaked (heated and dried) to form a coating film. Then, mixing (impregnation) and cross-linking of the resist pattern thickening material 1 to the resist pattern 3 occurs at the interface between the resist pattern 3 and the resist pattern thickening material 1, and as shown in FIG. The mixing (impregnation) layer is formed at the interface between the pattern 3 and the resist pattern thickening material 1. Thereafter, as shown in FIG. 2 (e), when development processing is performed, a portion of the applied resist pattern thickening material 1 that is not mixed with the resist pattern 3 is dissolved and removed, and an inner layer resist pattern 10b ( A thickened resist pattern 10 having a surface layer 10a is formed (developed) on the resist pattern 3).
The development processing may be water development or development with an alkaline aqueous solution, but water development is preferable in that the development processing can be efficiently performed at low cost.
[0074]
The thickened resist pattern 10 has a surface layer 10a formed by mixing the resist pattern thickening material 1 on the surface of the inner layer resist pattern 10b (resist pattern 3). Since the resist pattern 10 is thickened by the thickness of the surface layer 10a compared to the resist pattern 3 (inner layer resist pattern 10b), the width of the resist removal pattern formed by the thickened resist pattern 10 is the resist pattern. 3 (the inner resist pattern 10b) is smaller than the width of the resist missing pattern, and the resist missing pattern formed by the thickened resist pattern 10 is fine.
[0075]
The surface layer 10a in the thickened resist pattern 10 is formed of the resist pattern thickening material 1, and the resist pattern thickening material 1 is made of a resin having the cyclic structure compound and the cyclic structure in part. Since at least one of them is contained, the etching resistance is remarkably excellent. In this case, even if the resist pattern 3 (inner layer resist pattern 10b) is a material having poor etching resistance, the thickened resist pattern 10 having the surface layer 10a having excellent etching resistance on the surface thereof can be formed.
In the thickened resist pattern 10, the boundary between the inner layer resist pattern 10b and the surface layer 10a may be clear or unclear.
[0076]
The resist pattern manufactured by the resist pattern forming method of the present invention has a surface layer formed by mixing the resist pattern thickening material of the present invention on the surface of the resist pattern. Since the resist pattern thickening material contains at least one of the cyclic structure compound and the resin partially containing the cyclic structure, even if the resist pattern is a material having poor etching resistance, A resist pattern having a surface layer with excellent etching resistance on the surface of the resist pattern can be efficiently produced. Further, since the thickened resist pattern manufactured by the method for manufacturing a resist pattern of the present invention is thickened by the thickness of the surface layer compared to the resist pattern, the thickened resist pattern 10 manufactured is The width of the resist omission pattern formed by the above method is smaller than the width of the resist omission pattern formed by the resist pattern before being thickened. A pattern can be formed efficiently.
[0077]
The thickened resist pattern manufactured by the resist pattern manufacturing method of the present invention includes, for example, a mask pattern, a reticle pattern, a magnetic head, an LCD (liquid crystal display), a PDP (plasma display panel), a SAW filter (surface acoustic wave filter). ), Etc., optical components used for connection of optical wiring, microparts such as microactuators, and semiconductor devices can be suitably used for manufacturing, and are suitable for the semiconductor device of the present invention and its manufacturing method described later. Can be used for
[0078]
(Semiconductor device and manufacturing method thereof)
The semiconductor device of the present invention is not particularly limited except that it includes at least a pattern formed using the resist pattern of the present invention, and includes a known member appropriately selected according to the purpose. .
As a specific example of the semiconductor device of the present invention, a flash memory, a DRAM, an FRAM, and the like are preferable.
The semiconductor device of the present invention can be preferably manufactured by the method for manufacturing a semiconductor device of the present invention described below.
[0079]
The method for manufacturing a semiconductor device of the present invention includes a resist pattern forming step and a patterning step, and further includes other steps appropriately selected as necessary.
[0080]
In the resist pattern forming step, after forming a resist pattern on a base (underlayer), the resist pattern thickening material of the present invention is applied so as to cover the surface of the resist pattern, thereby thickening the resist pattern. This is a step of forming a thickened resist pattern.
Examples of the base (base layer) include surface layers of various members in a semiconductor device, and preferred examples include a substrate such as a silicon wafer or a surface layer thereof. The resist pattern is as described above. The application method is as described above. Further, after the coating, it is preferable to perform the above-described pre-baking, cross-linking baking or the like.
[0081]
The patterning step is a step of patterning the base (base layer) by performing etching or the like using the thickened resist pattern formed by the resist pattern forming step (using as a mask pattern or the like).
There is no restriction | limiting in particular as the said etching method, Although it can select suitably according to the objective from well-known methods, For example, dry etching is mentioned suitably. The etching conditions are not particularly limited and can be appropriately selected depending on the purpose.
[0082]
As said other process, a surfactant application | coating process, a development processing process, etc. are mentioned suitably, for example.
[0083]
The surfactant applying step is a step of applying the surfactant to the surface of the inner layer resist pattern before the resist pattern forming step.
The surfactant is not particularly limited and may be appropriately selected depending on the intended purpose. For example, those described above are preferably used, and examples include polyoxyethylene-polyoxypropylene condensate compounds, polyoxyalkylene alkyl ethers. Compounds, polyoxyethylene alkyl ether compounds, polyoxyethylene derivative compounds, sorbitan fatty acid ester compounds, glycerin fatty acid ester compounds, primary alcohol ethoxylate compounds, phenol ethoxylate compounds, nonylphenol ethoxylates, octylphenol ethoxylates, lauryl alcohol Ethoxylate, oleyl alcohol ethoxylate, fatty acid ester, amide, natural alcohol, ethylenediamine, secondary alcohol ethoxylate, alcohol Kirukachion based, amide-type quaternary cationic, ester quaternary cationic, amine oxide, and the like betaine.
[0084]
The development processing step is a step of developing the applied resist pattern thickening material after the resist pattern forming step and before the patterning step. The development processing is as described above.
[0085]
According to the semiconductor device manufacturing method of the present invention, for example, various semiconductor devices including flash memory, DRAM, FRAM, and the like can be efficiently manufactured.
[0086]
【Example】
Examples of the present invention will be specifically described below, but the present invention is not limited to these examples.
[0087]
Example 1
-Preparation of resist pattern thickening material-
Resist pattern thickening materials 1A to 1J of the present invention having the compositions shown in Table 1 were prepared. In Table 1, the unit of numerical values in parentheses represents parts by mass. In the column of “resin”, “KW-3” represents a polyvinyl acetal resin (manufactured by Sekisui Chemical Co., Ltd.), and “PVA” represents a polyvinyl alcohol resin (manufactured by Kuraray Co., Ltd., Poval 117). In the “crosslinking agent” column, “uril” represents tetramethoxymethyl glycoluril, “urea” represents N, N′-dimethoxymethyldimethoxyethylene urea, and “melamine” represents hexamethoxymethylmelamine. . In the “surfactant” column, “TN-80” represents a nonionic surfactant (manufactured by Asahi Denka Co., Ltd., primary alcohol ethoxylate surfactant), and “PC-6” It represents an ionic surfactant (Asahi Denka Co., Ltd., special phenol ethoxylate surfactant), and “PC-8” is a nonionic surfactant (Asahi Denka Co., Ltd., special phenol ethoxylate surfactant). "PC-12" represents a nonionic surfactant (Asahi Denka Co., Ltd., special phenol ethoxylate surfactant). Further, as a main solvent component excluding the resin, the crosslinking agent and the cyclic structure-containing compound, a mixed solution of pure water (deionized water) and isopropyl alcohol (mass ratio is pure water (deionized water): isopropyl alcohol) = 98.6: 0.4) was used.
[0088]
[Table 1]

[0089]
-Resist pattern and its manufacture-
The resist pattern thickening materials 1A to 1J of the present invention prepared as described above are formed on the hole pattern formed by the ArF resist (manufactured by Sumitomo Chemical Co., Ltd., PAR700, alicyclic resist) by a spin coating method. After first applying under the condition of 1000 rpm / 5 s and then under the condition of 3500 rpm / 40 s, the pre-baking is performed under the condition of 85 ° C./70 s, and the crosslinking baking is further performed under the condition of 110 ° C./70 s. Resist pattern thickening materials 1A-1J are rinsed with water for 60 seconds, uncrosslinked portions are removed, and resist patterns thickened with resist pattern thickening materials 1A-1J are developed to produce resist patterns. did.
[0090]
About the size of the pattern formed by the manufactured resist pattern (thickened resist pattern) (size of the resist removal pattern formed by the thickened resist pattern), the size of the pattern formed by the initial pattern ( Table 2 shows the resist omission pattern size formed by the resist pattern before thickening. In Table 2, “1A” to “1J” correspond to the resist pattern thickening materials 1A to 1J.
[0091]
[Table 2]

[0092]
The resist pattern thickening materials 1A to 1J of the present invention prepared as described above were initially applied at 1000 rpm / on a line & space pattern formed by the ArF resist (manufactured by Sumitomo Chemical Co., Ltd., PAR700) by spin coating. Next, after coating at 5500 s under conditions of 3500 rpm / 40 s, the pre-baking is performed at 85 ° C./70 s, and the cross-linking baking is further performed at 110 ° C./70 s. Thickening materials 1A-1J were rinsed for 60 seconds, uncrosslinked portions were removed, and resist patterns thickened with resist pattern thickening materials 1A-1J were developed to produce resist patterns.
[0093]
About the size of the pattern formed by the manufactured resist pattern (thickened resist pattern) (size of the resist removal pattern formed by the thickened resist pattern), the size of the pattern formed by the initial pattern ( Table 3 shows the resist omission pattern size formed by the resist pattern before thickening. In Table 3, “1A” to “1J” correspond to the resist pattern thickening materials 1A to 1J.
[0094]
[Table 3]

[0095]
From the results of Tables 2 and 3, it can be seen that the resist pattern thickening material of the present invention can be applied to both hole patterns and line & space patterns, and can be thickened. When the resist pattern thickening material of the present invention is used for forming a hole pattern, the inner diameter of the hole pattern can be made narrow and fine, and when used for forming a linear pattern, the linear pattern width (the The distance between resist patterns forming a linear pattern can be made small and fine, and when used for forming an isolated pattern, the area of the isolated pattern can be increased.
[0096]
Next, on the surface of the resist formed on the silicon substrate, the resist pattern thickening materials 1D, 1H, 1I, and 1J of the present invention were applied and crosslinked to form a surface layer having a thickness of 0.5 μm. These surface layers, the KrF resist for comparison (manufactured by Shipley Co., Ltd., UV-6), and polymethyl methacrylate (PMMA) for comparison are etched with an etching apparatus (parallel plate type RIE apparatus, Fujitsu Limited). Made, Pμ = 200 W, pressure = 0.02 Torr, CF₄Etching was performed for 3 minutes under the condition of gas = 100 sccm, the amount of film reduction of the sample was measured, the etching rate was calculated, and relative evaluation was performed based on the etching rate of the KrF resist.
[0097]
[Table 4]

[0098]
From the results shown in Table 4, it can be seen that the etching resistance of the resist pattern thickening material of the present invention is close to that of the KrF resist and is significantly superior to the PMMA.
[0099]
Next, when the resist pattern thickening materials 1A to 1J of the present invention are applied on the inner layer resist pattern on the wafer substrate left outside the clean room for one month after the exposure, the same as in the case of applying immediately after the exposure. A resist pattern thickening effect was obtained.
As a result, the resist pattern thickening material of the present invention does not thicken the inner layer resist pattern by utilizing a cross-linking reaction by acid diffusion as in the conventional technique called RELACS. It is presumed that the resist pattern is thickened depending on the compatibility with the pattern.
[0100]
(Example 2)
-Preparation of resist pattern thickening material-
Resist pattern thickening materials 2A to 2M of the present invention having the compositions shown in Table 5 were prepared. In Table 5, the unit of numerical values in parentheses represents parts by mass. “Resin 1”, “Resin 2” and “Resin 3” in the “Resin” column are synthesized as described below, and “Uryl” in the “Crosslinking agent” column is tetramethoxymethylglycoluril. "Urea" represents N, N'-dimethoxymethyldimethoxyethylene urea, and "melamine" represents hexamethoxymethylmelamine. “TN-80” in the “Surfactant” column represents a nonionic surfactant (Asahi Denka Co., Ltd., primary alcohol ethoxylate surfactant). Further, as a main solvent component excluding the resin, the crosslinking agent and the surfactant, a mixed solution of pure water (deionized water) and isopropyl alcohol (mass ratio is pure water (deionized water): isopropyl alcohol = 16: 0.75) was used.
[0101]
The “resin 1” is a “polyvinyl β-resorcin acetal resin” synthesized as follows. That is, 10 g of polyvinyl alcohol 500 (manufactured by Kanto Chemical) was dissolved in 100 g of deionized water, 0.8 g of concentrated hydrochloric acid was added, and the mixture was stirred at 40 ° C. for 3 hours. To this was added 2.36 g of β-resorcinaldehyde (manufactured by Tokyo Chemical Industry), and the mixture was stirred at the same temperature for 6 hours. The reaction solution was returned to room temperature and neutralized by adding 15% by mass of TMAH (tetramethylammonium hydroxide) solution. This solution was added dropwise to 2 L ethanol to separate the resin. The resin was filtered off with a glass filter and dried under reduced pressure in a vacuum baking oven at 45 ° C. for 6 hours. This operation was repeated three times to synthesize the target polyvinyl β-resorcin acetal resin. The yield was 6.8g. The acetalization rate determined by NMR was 20.6 mol%.
[0102]
  The “resin 2” is “polyvinyl-2,3-dihydroxybenzacetal resin” synthesized as follows. That is, in the synthesis of “resin 1”, except that β-resorcinaldehyde was replaced with 2,3-dihydroxybenzaldehyde, the same as the synthesis of “resin 1”,2, 3-Dihydroxybenzacetal resin was obtained. The yield was 6.6g. When the acetalization rate was determined by NMR, it was 20.1 mol%.
[0103]
The “resin 3” is “polyvinyl β-resorcin acetal resin” synthesized as follows. That is, 10 g of polyvinyl alcohol 500 (manufactured by Kanto Chemical Co., Inc.) was dissolved in 100 g of deionized water, 0.4 g of concentrated hydrochloric acid was added, and the mixture was stirred at 40 ° C. for 3 hours. To this, 0.5 g of β-resorcinaldehyde (manufactured by Tokyo Chemical Industry Co., Ltd.) was added and stirred at the same temperature for 6 hours. The reaction solution was returned to room temperature and neutralized by adding 15% by mass of TMAH (tetramethylammonium hydroxide) solution. This solution was added dropwise to 2 L of ethanol to separate the resin. The resin was filtered off with a glass filter and dried under reduced pressure in a vacuum baking oven at 45 ° C. for 6 hours. This operation was repeated three times to obtain the target polyvinyl β-resorcin acetal resin. The yield was 4.1 g. When the acetalization rate was determined by NMR, it was 3.7 mol%.
[0104]
[Table 5]

[0105]
-Resist pattern and its manufacture-
The resist pattern thickening materials 2A to 2L of the present invention prepared as described above are first formed at 1000 rpm / 5 s by spin coating on the hole pattern formed by the ArF resist (manufactured by Sumitomo Chemical Co., Ltd., PAR700). Then, after coating at 3500 rpm / 40 s, the pre-baking is performed at 85 ° C./70 s, and the cross-linking baking is further performed at 110 ° C./70 s. Then, the resist pattern is thickened with pure water. Resin patterns 2A-2L were rinsed for 60 seconds, uncrosslinked portions were removed, and resist patterns thickened with resist pattern thickening materials 2A-2L were developed to produce resist patterns.
[0106]
Table 6 shows the size of the pattern formed by the manufactured resist pattern (thickened resist pattern) together with the size of the pattern formed by the initial pattern size (size of the hole pattern before thickening). It was. In Table 6, “2A” to “2L” correspond to the resist pattern thickening materials 2A to 2L.
[0107]
[Table 6]

[0108]
The resist pattern thickening materials 2A to 2L of the present invention prepared as described above were initially applied at 1000 rpm / on the line & space pattern formed by the ArF resist (manufactured by Sumitomo Chemical Co., Ltd., PAR700) by spin coating. Next, after coating at 5500 s under conditions of 3500 rpm / 40 s, the pre-baking is performed at 85 ° C./70 s, and the cross-linking baking is further performed at 110 ° C./70 s. The thickening materials 2A to 2L were rinsed for 60 seconds, the uncrosslinked portion was removed, and the resist pattern thickened with the resist pattern thickening materials 2A to 2L was developed to produce a resist pattern.
[0109]
Table 7 shows the size of the pattern formed by the manufactured resist pattern (thickened resist pattern) together with the size of the pattern formed by the initial pattern size (size of the line and space pattern before thickening). It was shown to. In Table 7, “2A” to “2L” correspond to the resist pattern thickening materials 2A to 2L.
[0110]
[Table 7]

[0111]
From the results of Tables 6 and 7, it can be seen that the resist pattern thickening material of the present invention can be applied to both hole patterns and line & space patterns, and can be thickened. When the resist pattern thickening material of the present invention is used for forming a hole pattern, the inner diameter of the hole pattern can be made narrow and fine, and when used for forming a linear pattern, the linear pattern width (the The distance between resist patterns forming a linear pattern can be made small and fine, and when used for forming an isolated pattern, the area of the isolated pattern can be increased.
[0112]
Next, on the surface of the resist formed on the silicon substrate, the resist pattern thickening materials 2A, 2G, and 2M of the present invention were applied and crosslinked to form a surface layer having a thickness of 0.5 μm. These surface layers, the KrF resist for comparison (manufactured by Shipley Co., Ltd., UV-6), and polymethyl methacrylate (PMMA) for comparison are etched with an etching apparatus (parallel plate type RIE apparatus, Fujitsu Limited). Manufactured), Pμ = 200 W, pressure = 0.02 Torr, CF₄Etching was performed for 3 minutes under the condition of gas = 100 sccm, the amount of film reduction of the sample was measured, the etching rate was calculated, and relative evaluation was performed based on the etching rate of the KrF resist.
[0113]
[Table 8]

[0114]
From the results shown in Table 8, it can be seen that the etching resistance of the resist pattern thickening material of the present invention is close to that of the KrF resist and is significantly superior to the PMMA. Note that the resist pattern thickening material 2M has an arylacetal content of less than 5 mol%, which is slightly inferior to the resist pattern thickening materials 2A and G in which the content is 5 mol% or more. A trend was observed.
[0115]
Next, when the resist pattern thickening materials 2A to 2M of the present invention are applied on the resist pattern on the wafer substrate left outside the clean room for one month after exposure, the same pattern as that applied immediately after exposure is applied. A thickening effect was obtained.
As a result, the resist pattern thickening material of the present invention does not thicken the resist pattern by utilizing a cross-linking reaction by acid diffusion as in the conventional technique called RELACS. It is presumed that the resist pattern is thickened depending on the compatibility between the resist pattern.
[0116]
(Example 3)
-Flash memory and its manufacture-
Example 3 is an example of a semiconductor device of the present invention using the resist pattern thickening material of the present invention and a manufacturing method thereof. In this Example 3, the following resist films 26, 27, 29, 32 and 34 are thickened by the same method as in Examples 1 and 2 using the resist pattern thickening material of the present invention. It has been done.
[0117]
3A and 3B are top views (plan views) of a FLASH EPROM called FLOTOX type or ETOX type called FLOTOX type or ETOX type, and FIGS. 5 (d) to (f) and FIGS. 6 (g) to (i) are schematic cross-sectional views for explaining an example of the manufacturing method of the FLASH EPROM, and the left diagrams in FIGS. FIG. 5 is a schematic cross-sectional view (A-direction cross-section) in the gate width direction (X direction in FIG. 3) of a portion where a MOS transistor having a floating gate electrode is formed in the memory cell portion (first element region) Is a memory cell portion of the same portion as the left figure, and is a schematic cross section (B direction cross section) in the gate length direction (Y direction in FIG. 3) orthogonal to the X direction, and the right figure is a peripheral circuit portion ( FIG. 4 is a schematic cross-sectional view (cross-section in the direction A in FIG. 3) of a portion where a MOS transistor in a second element region) is formed.
[0118]
First, as shown in FIG. 4A, SiO is selectively formed in an element isolation region on a p-type Si substrate 22.₂A field oxide film 23 made of a film was formed. Thereafter, the first gate insulating film 24a in the MOS transistor in the memory cell portion (first element region) is thermally oxidized to a thickness of 100 to 300 mm by SiO.₂In another process, the second gate insulating film 24b in the MOS transistor in the peripheral circuit portion (second element region) is thermally oxidized to a thickness of 100 to 500 mm by thermal oxidation.₂It was formed by a film. When the first gate insulating film 24a and the second gate insulating film 24b have the same thickness, an oxide film may be formed simultaneously in the same process.
[0119]
Next, in order to form a MOS transistor having an n-type depletion type channel in the memory cell portion (left and center diagrams in FIG. 4A), the peripheral circuit portion ( The right side of FIG. 4A was masked with the resist film 26. Then, in the region to be the channel region immediately below the floating gate electrode, the dose amount is 1 × 10 6 as an n-type impurity.¹¹~ 1x10¹⁴cm^-2Phosphorus (P) or arsenic (As) was introduced by ion implantation to form the first threshold control layer 25a. Note that the dose amount and the conductivity type of the impurity at this time can be appropriately selected depending on whether the depletion type or the accumulation type is used.
[0120]
Next, in order to form a MOS transistor having an n-type depletion type channel in the peripheral circuit portion (the right diagram of FIG. 4B), a memory cell portion (FIG. The left figure and the middle figure of FIG. Then, a dose amount of 1 × 10 6 as an n-type impurity is formed in a region to be a channel region immediately below the gate electrode.¹¹~ 1x10¹⁴cm^-2Next, phosphorus (P) or arsenic (As) was introduced by ion implantation to form the second threshold control layer 25b.
[0121]
Next, as a floating gate electrode of the MOS transistor in the memory cell portion (the left diagram and the central diagram in FIG. 4C) and a gate electrode of the MOS transistor in the peripheral circuit portion (the right diagram in FIG. 4C) A first polysilicon film (first conductor film) 28 having a thickness of 500 to 2000 mm was formed on the entire surface.
[0122]
Thereafter, as shown in FIG. 5 (d), the first polysilicon film 28 is patterned by a resist film 29 formed as a mask, and the MOS transistor of the memory cell portion (the left diagram and the central diagram in FIG. 5 (d)) is formed. The floating gate electrode 28a was formed. At this time, as shown in FIG. 5D, patterning is performed so that the final dimension width is in the X direction, and the region that becomes the S / D region layer is covered with the resist film 29 without patterning in the Y direction. I left it.
[0123]
Next, as shown in the left diagram and the central diagram in FIG. 5E, after removing the resist film 29, the floating gate electrode 28a is covered so as to cover SiO 2.₂A capacitor insulating film 30a made of a film was formed by thermal oxidation so as to have a thickness of about 200 to 500 mm. At this time, SiO is also formed on the first polysilicon film 28 in the peripheral circuit portion (the right diagram in FIG. 5E).₂A capacitor insulating film 30b made of a film is formed. Here, the capacitor insulating films 30a and 30b are made of SiO.₂It is made of only film, but it is SiO₂Film and Si₃N₄The film may be formed of a composite film in which two to three layers are stacked.
[0124]
Next, as shown in FIG. 5E, the thickness of the second polysilicon film (second conductor film) 31 that becomes the control gate electrode so as to cover the floating gate electrode 28a and the capacitor insulating film 30a. It formed so that it might become 500-2000 mm.
[0125]
Next, as shown in FIG. 5 (f), the memory cell portion (left and center views of FIG. 5 (f)) is masked with a resist film 32, and the peripheral circuit portion (right of FIG. 5 (f)) is masked. The second polysilicon film 31 and the capacitor insulating film 30b in the figure were sequentially removed by etching, and the first polysilicon film 28 was exposed.
[0126]
Next, as shown in FIG. 6G, the second polysilicon film 31, the capacitor insulating film 30a and the X direction of the memory cell portion (the left figure and the middle figure in FIG. 6G) are patterned only in the X direction. Using the resist film 32 as a mask, the first polysilicon film 28a is patterned in the Y direction so as to have the final dimensions of the first gate portion 33a, and the control gate electrode 31a / capacitor having a width of about 1 μm in the Y direction. A stack of insulating film 30c / floating gate electrode 28c is formed, and a second gate portion is formed on resist film 32 as a mask with respect to first polysilicon film 28 in the peripheral circuit portion (the right view of FIG. 6G). Patterning was performed to obtain a final dimension of 33b to form a gate electrode 28b having a width of about 1 μm.
[0127]
Next, using the stack of the control gate electrode 31a / capacitor insulating film 30c / floating gate electrode 28c in the memory cell portion (the left and center views of FIG. 6H) as a mask, the silicon substrate 22 in the element formation region is dosed. Quantity 1 × 10¹⁴~ 1x10¹⁶cm^-2Phosphorus (P) or arsenic (As) is introduced by ion implantation to form n-type S / D region layers 35a and 35b, and the gate of the peripheral circuit portion (the right diagram in FIG. 5 (h)). Using the electrode 28b as a mask, a dose amount of 1 × 10 6 as an n-type impurity in the Si substrate 22 in the element formation region¹⁴~ 1x10¹⁶cm^-2Phosphorus (P) or arsenic (As) was introduced by ion implantation to form S / D region layers 36a and 36b.
[0128]
Next, the first gate portion 33a of the memory cell portion (the left view and the center view of FIG. 6 (i)) and the second gate portion 33b of the peripheral circuit portion (the right view of FIG. 6 (i)) are connected to the PSG. An interlayer insulating film 37 made of a film was formed so as to have a thickness of about 5000 mm.
Thereafter, contact holes 38a and 38b and contact holes 39a and 39b are formed in the interlayer insulating film 37 formed on the S / D region layers 35a and 35b and the S / D region layers 36a and 36b, and then the S / D electrode 40a. And 40b and S / D electrodes 41a and 41b were formed.
As a result, as shown in FIG. 6I, a FLASH EPROM was manufactured as a semiconductor device.
[0129]
In this FLASH EPROM, the second gate insulating film 24b of the peripheral circuit portion (the right diagrams in FIGS. 4A to 6F) is formed from the first polysilicon film 28 or the gate electrode 28b from the beginning to the end. Since it is covered (the right figure in FIG. 5C to FIG. 6F), the second gate insulating film 24b keeps the thickness when it is first formed. Therefore, the thickness of the second gate insulating film 24b can be easily controlled, and the conductivity type impurity concentration for controlling the threshold voltage can be easily adjusted.
In the above embodiment, the first gate portion 33a is formed by first patterning with a predetermined width in the gate width direction (X direction in FIG. 3) and then patterning in the gate length direction (Y direction in FIG. 3). However, the pattern is patterned in the gate length direction (Y direction in FIG. 3) with a predetermined width, and then patterned in the gate width direction (X direction in FIG. 3). It is good.
[0130]
The manufacturing examples of FLASH EPROM shown in FIGS. 7A to 7C are the same as those shown in FIGS. 7A to 7C except that the steps shown in FIG. Is the same as in the above embodiment. That is, as shown in FIG. 7A, the second polysilicon film 31 in the left diagram and the central diagram in the memory cell portion FIG. 7A and the first diagram in the right diagram in the peripheral circuit diagram in FIG. 7A. A polycide film is formed by forming a refractory metal film (fourth conductor film) 42 made of a tungsten (W) film or a titanium (Ti) film on the polysilicon film 28 so as to have a thickness of about 2000 mm. Only differs from the above embodiment. The steps after FIG. 7A, that is, the steps shown in FIGS. 7B to 7C, were performed in the same manner as FIGS. 6G to 6I. The description of the same steps as those in FIGS. 6 (g) to (i) is omitted, and in FIGS. 7 (a) to (c), the same steps as those in FIGS. 6 (g) to (i) are indicated by the same symbols.
As a result, as shown in FIG. 7C, a FLASH EPROM was manufactured as a semiconductor device.
[0131]
In this FLASH EPROM, since the refractory metal films (fourth conductor films) 42a and 42b are provided on the control gate electrode 31a and the gate electrode 28b, the electric resistance value can be further reduced.
Here, although the refractory metal films (fourth conductor film) 42a and 42b are used as the refractory metal film (fourth conductor film), a refractory metal silicide film such as a titanium silicide (TiSi) film is used. May be used.
[0132]
The manufacturing example of the FLASH EPROM shown in FIGS. 8A to 8C is the same as that in the above embodiment in the second gate portion 33c of the peripheral circuit portion (second element region) (the right diagram in FIG. 8A). Similarly to the first gate portion 33a in the memory cell portion (first element region) (the left and center views in FIG. 8A), the first polysilicon film 28b (first conductor film) / SiO₂The structure is a film 30d (capacitor insulating film) / second polysilicon film 31b (second conductor film). As shown in FIG. 8B or 8C, the first polysilicon film 28b and the second polysilicon film are formed. This embodiment is the same as the above embodiment except that the gate electrode is formed by short-circuiting the film 31b.
[0133]
Here, as shown in FIG. 8B, the first polysilicon film 28b (first conductor film) / SiO 2₂An opening 52a penetrating the film 30d (capacitor insulating film) / second polysilicon film 31b (second conductor film) is formed at a location different from, for example, the second gate portion 33c shown in FIG. The first polysilicon film 28b and the second polysilicon film 31b are formed on the film 54 by embedding a third conductor film, for example, a refractory metal film 53a such as a W film or a Ti film in the opening 52a. Short circuit. Further, as shown in FIG. 8C, the first polysilicon film 28b (first conductor film) / SiO₂After forming the opening 52b penetrating the film 30d (capacitor insulating film) and exposing the lower first polysilicon film 28b at the bottom of the opening 52b, a third conductor film, for example, By embedding a refractory metal film 53b such as a W film or a Ti film, the first polysilicon film 28b and the second polysilicon film 31b are short-circuited.
[0134]
In this FLASH EPROM, since the second gate portion 33c of the peripheral circuit portion has the same structure as the first gate portion 33a of the memory cell portion, the peripheral circuit portion is simultaneously formed when the memory cell portion is formed. It can be formed, and the manufacturing process can be simplified and efficient.
Although the third conductor film 53a or 53b and the refractory metal film (fourth conductor film) 42 are separately formed here, they may be formed simultaneously as a common refractory metal film. Good.
[0135]
(Example 4)
-Manufacture of magnetic heads-
Example 4 relates to the manufacture of a magnetic head as an application example of the resist pattern of the present invention using the resist pattern thickening material of the present invention. In Example 3, the following resist patterns 102 and 126 were thickened by the same method as in Examples 1 and 2 using the resist pattern thickening material of the present invention.
[0136]
9A to 9D are process diagrams for explaining the manufacture of the magnetic head.
First, as shown in FIG. 9A, a resist film is formed on the interlayer insulating layer 100 so as to have a thickness of 6 μm, and exposure and development are performed to form an opening pattern for forming a spiral thin film magnetic coil. A resist pattern 102 having the following was formed.
Next, as shown in FIG. 9B, a thickness of 0.01 μm is formed on the resist pattern 102 and the portion where the resist pattern 102 is not formed on the interlayer insulating layer 100, that is, on the exposed surface of the opening 104. A plating base layer 106 formed by laminating a Ti adhesion film and a Cu adhesion film having a thickness of 0.05 μm was formed by vapor deposition.
Next, as shown in FIG. 9C, a portion of the interlayer insulating layer 100 where the resist pattern 102 is not formed, that is, on the surface of the plating base layer 106 formed on the exposed surface of the opening 104, A thin film conductor 108 made of a Cu plating film having a thickness of 3 μm was formed.
Next, as shown in FIG. 9D, when the resist pattern 102 is dissolved and removed and lifted off from the interlayer insulating layer 100, a thin film magnetic coil 110 having a spiral pattern of the thin film conductor 108 is formed.
A magnetic head was manufactured as described above.
[0137]
In the magnetic head obtained here, since the spiral pattern is finely formed by the resist pattern 102 thickened using the thickening material of the present invention, the thin film magnetic coil 110 is fine and fine. Moreover, it is excellent in mass productivity.
[0138]
10 to 15 are process diagrams for explaining the manufacture of another magnetic head.
As shown in FIG. 10, a gap layer 114 was formed on a nonmagnetic substrate 112 made of ceramic by a sputtering method. Although not shown, an insulating layer made of silicon oxide and a conductive underlayer made of Ni—Fe permalloy are previously formed on the nonmagnetic substrate 112 by sputtering, and the lower magnetic layer made of Ni—Fe permalloy is formed. A layer is formed. Then, a resin insulating film 116 was formed from a thermosetting resin in a predetermined region on the gap layer 114 excluding a portion that becomes a magnetic tip of the lower magnetic layer (not shown). Next, a resist material was applied onto the resin insulating film 116 to form a resist film 118.
[0139]
Next, as shown in FIG. 11, the resist film 118 was exposed and developed to form a spiral pattern. Then, as shown in FIG. 12, the resist film 118 having the spiral pattern was subjected to a thermosetting process at several hundred degrees C. for about one hour to form a first spiral pattern 120 having a protrusion shape. Further, a conductive base layer 122 made of Cu was formed on the surface.
[0140]
Next, as shown in FIG. 13, a resist material is applied onto the conductive base layer 122 by spin coating to form a resist film 124, and then the resist film 124 is patterned on the first spiral pattern 120. A resist pattern 126 was formed.
Next, as shown in FIG. 14, a Cu conductor layer 128 was formed by plating on the exposed surface of the conductive base layer 122, that is, on a portion where the resist pattern 126 was not formed. Thereafter, as shown in FIG. 15, the resist pattern 126 was dissolved and removed to lift off the conductive base layer 122, thereby forming a spiral thin film magnetic coil 130 made of the Cu conductor layer 128.
Thus, a magnetic head having the magnetic layer 132 on the resin insulating film 116 and having the thin film magnetic coil 130 provided on the surface as shown in the plan view of FIG. 16 was manufactured.
[0141]
In the magnetic head obtained here, the spiral pattern is finely formed by the resist pattern 126 thickened using the resist pattern thickening material of the present invention, so that the thin film magnetic coil 130 is fine and fine. In addition, it is excellent in mass productivity.
[0142]
Here, it will be as follows if the preferable aspect of this invention is appended.
(Appendix 1) A resist pattern thickening material comprising a resin, a crosslinking agent, and a cyclic structure-containing compound.
(Supplementary note 2) The resist pattern thickening material according to supplementary note 1, which is water-soluble or alkali-soluble.
(Appendix 3) The appendix 1 according to any one of appendices 1 and 2, wherein the cyclic structure compound is soluble in 1 g or more in either 100 g of water at 25 ° C. or 100 g of 2.38 mass% tetramethylammonium hydroxide. Resist pattern thickening material.
(Appendix 4) The resist pattern thickening material according to any one of appendices 1 to 3, wherein the cyclic structure compound has two or more polar groups.
(Supplementary note 5) The resist pattern thickening material according to supplementary note 4, wherein the polar group is selected from a hydroxyl group, an amino group, a sulfonyl group, a carbonyl group, a carboxyl group and derivatives thereof.
(Appendix 6) The resist pattern thickening material according to any one of appendices 1 to 5, wherein the cyclic structure compound is at least one selected from an aromatic compound, an alicyclic compound, and a heterocyclic compound.
(Appendix 7) The aromatic compound is selected from a polyphenol compound, an aromatic carboxylic acid compound, a naphthalene polyhydric alcohol compound, a benzophenone compound, a flavonoid compound, a derivative thereof, and a glycoside thereof,
The alicyclic compound is selected from polycycloalkanes, cycloalkanes, steroids, derivatives thereof and glycosides thereof,
The resist pattern thickening material according to appendix 6, wherein the heterocyclic compound is selected from pyrrolidine, pyridine, imidazole, oxazole, morpholine, pyrrolidone, furan, pyran, saccharide, and derivatives thereof.
(Supplementary note 8) The resist pattern thickening material according to any one of supplementary notes 1 to 7, wherein the resin has a ring structure at least in part.
(Appendix 9) A resist pattern thickening material comprising a resin having a cyclic structure at least in part and a crosslinking agent.
(Supplementary note 10) The resist pattern thickening material according to any one of supplementary notes 8 to 9, wherein the cyclic structure is selected from an aromatic compound, an alicyclic compound, and a heterocyclic compound.
(Additional remark 11) The resist pattern thickening material in any one of Additional remark 8 to 10 whose molar content rate in resin of cyclic structure is 5 mol% or more.
(Supplementary note 12) The resist pattern thickening material according to any one of supplementary notes 1 to 11, wherein the resin is water-soluble or alkali-soluble.
(Supplementary note 13) The resist pattern thickening material according to any one of supplementary notes 1 to 12, wherein the resin is at least one selected from polyvinyl alcohol, polyvinyl acetal, and polyvinyl acetate.
(Supplementary note 14) The resist pattern thickening material according to any one of supplementary notes 1 to 13, wherein the resin contains 5 to 40 mass% of polyvinyl acetal.
(Supplementary note 15) The resist pattern thickening material according to any one of supplementary notes 1 to 14, wherein the resin has two or more polar groups.
(Supplementary note 16) The resist pattern thickening material according to supplementary note 15, wherein the polar group is selected from a hydroxyl group, an amino group, a sulfonyl group, a carbonyl group, a carboxyl group and derivatives thereof.
(Supplementary note 17) The resist pattern thickening material according to any one of supplementary notes 1 to 16, wherein the crosslinking agent is at least one selected from a melamine derivative, a urea derivative, and a uril derivative.
(Supplementary note 18) The resist pattern thickening material according to any one of supplementary notes 1 to 17, comprising a surfactant.
(Supplementary note 19) In any one of supplementary notes 1 to 18, wherein the surfactant is at least one selected from a nonionic surfactant, a cationic surfactant, an anionic surfactant, and an amphoteric surfactant. The resist pattern thickening material described.
(Supplementary note 20) The nonionic surfactant is a polyoxyethylene-polyoxypropylene condensate compound, a polyoxyalkylene alkyl ether compound, a polyoxyethylene alkyl ether compound, a polyoxyethylene derivative compound, a sorbitan fatty acid ester compound, a glycerin fatty acid. Select from ester compounds, primary alcohol ethoxylate compounds, phenol ethoxylate compounds, alkoxylate surfactants, fatty acid ester surfactants, amide surfactants, alcohol surfactants, and ethylenediamine surfactants And
The cationic surfactant is selected from alkyl cationic surfactants, amide type quaternary cationic surfactants, and ester type quaternary cationic surfactants;
Item 20. The resist pattern thickening material according to appendix 19, wherein the amphoteric surfactant is selected from an amine oxide surfactant and a betaine surfactant.
(Supplementary note 21) The resist pattern thickening material according to any one of supplementary notes 1 to 20, comprising an organic solvent.
(Supplementary note 22) In Supplementary note 21, the organic solvent is at least one selected from alcohol solvents, chain ester solvents, cyclic ester solvents, ketone solvents, chain ether solvents, and cyclic ether solvents. The resist pattern thickening material described.
(Additional remark 23) It has a surface layer on a resist pattern, The ratio (resist pattern / surface layer) of the etching rate (Å / s) of this surface layer and the etching rate (Å / s) of this resist pattern under the same conditions Is a resist pattern characterized by being 1.1 or more.
(Supplementary note 24) The resist pattern according to supplementary note 23, wherein the surface layer contains a cyclic structure compound.
(Supplementary note 25) The resist pattern according to any one of supplementary notes 23 to 24, wherein the content of the cyclic structure compound gradually decreases from the surface layer toward the inside.
(Additional remark 26) After forming a resist pattern, the resist pattern thickening material in any one of Additional remarks 1 to 22 is apply | coated so that the surface of this resist pattern may be covered. Resist pattern.
(Additional remark 27) After forming a resist pattern, the resist pattern thickening material in any one of additional marks 1 to 22 is apply | coated so that the surface of this resist pattern may be covered, The manufacturing method of the resist pattern characterized by the above-mentioned.
(Supplementary note 28) The method for producing a resist pattern according to supplementary note 27, wherein after the resist pattern thickening material is applied, the resist pattern thickening material is developed.
(Additional remark 29) The manufacturing method of the resist pattern of Additional remark 28 with which a development process is performed using a pure water.
(Additional remark 30) It has a surface layer on a resist pattern, and the ratio (resist pattern / surface layer) of the etching rate (Å / s) of the surface layer and the etching rate (Å / s) of the resist pattern under the same conditions 30. The method for producing a resist pattern according to any one of appendices 27 to 29, wherein the value is 1.1 or more.
(Supplementary note 31) The resist pattern according to supplementary note 30, wherein the surface layer contains at least one of a cyclic structure compound and a cyclic structure.
(Supplementary note 32) The resist pattern according to any one of supplementary notes 30 to 31, wherein the content of at least one of the cyclic structure compound and the cyclic structure gradually decreases from the surface layer toward the inside.
(Additional remark 33) The semiconductor device characterized by having at least the pattern formed using the resist pattern of Additional remarks 23-26.
(Appendix 34) After forming a resist pattern on the underlayer, the resist pattern is thickened by applying the resist pattern thickening material according to any one of Appendixes 1 to 22 so as to cover the surface of the resist pattern. And a patterning step of patterning the underlayer by etching using the thickened resist pattern as a mask.
(Additional remark 35) The manufacturing method of the semiconductor device of Additional remark 34 in which the resist pattern was formed with the ArF resist.
(Supplementary note 36) The supplementary note 35, wherein the ArF resist is at least one selected from an acrylic resist having a cycloaliphatic functional group in the side chain, a cycloolefin-maleic anhydride resist, and a cycloolefin resist. Semiconductor device manufacturing method.
(Supplementary Note 37) Prior to the resist pattern formation step, a polyoxyethylene-polyoxypropylene condensate compound, a polyoxyalkylene alkyl ether compound, a polyoxyethylene alkyl ether compound, a polyoxyethylene derivative compound, sorbitan is formed on the surface of the resist pattern. From Supplementary Note 34 including a surfactant coating step of coating a nonionic surfactant that is at least one selected from a fatty acid ester compound, a glycerin fatty acid ester compound, a primary alcohol ethoxylate compound, and a phenol ethoxylate compound 36. A method of manufacturing a semiconductor device according to any one of 36.
[0143]
【The invention's effect】
According to the present invention, the conventional problems can be solved in response to the demand.
In addition, according to the present invention, the resist pattern is coated on a resist pattern formed of ArF resist or the like so that the resist pattern is thickened, and a fine resist omission pattern exceeding the exposure limit of a light source of an existing exposure apparatus can be obtained at low cost. A resist pattern thickening material that can be easily formed and that can improve the etching resistance of the resist pattern can be provided.
Further, according to the present invention, it is possible to provide a resist pattern that can be patterned using an ArF excimer laser or the like, has a fine structure, and has excellent etching resistance.
In addition, according to the present invention, ArF excimer laser light can be used as exposure light (light used for exposure), which is excellent in mass productivity, and a fine pattern formed by a resist pattern can be finely exceeded the light exposure limit. It is possible to provide a method for producing a resist pattern that can be formed at low cost with ease and with improved etching resistance.
Moreover, according to the present invention, a high-performance semiconductor device having a fine pattern formed by a resist pattern can be provided.
According to the present invention, an ArF excimer laser beam can be used as exposure light (light used for exposure), and a semiconductor device manufacturing method capable of efficiently mass-producing a high-performance semiconductor device having a fine pattern Can be provided.
[Brief description of the drawings]
FIG. 1 is a schematic view for explaining the mechanism of thickening a resist pattern using the resist pattern thickening material of the present invention.
FIG. 2 is a schematic view for explaining an example of a method for producing a resist pattern according to the present invention.
FIG. 3 is a top view for explaining a FLASH EPROM which is an example of a semiconductor device of the present invention.
FIG. 4 is a schematic cross-sectional view (No. 1) for explaining the manufacturing method of the FLASH EPROM which is an example relating to the manufacturing method of the semiconductor device of the present invention.
FIG. 5 is a schematic cross-sectional view (No. 2) for explaining the manufacturing method of the FLASH EPROM as an example relating to the manufacturing method of the semiconductor device of the present invention;
FIG. 6 is a schematic cross-sectional view (No. 3) for explaining the manufacturing method of the FLASH EPROM which is an example relating to the manufacturing method of the semiconductor device of the present invention;
FIG. 7 is a schematic cross-sectional view for explaining a manufacturing method of FLASH EPROM, which is another example of the manufacturing method of the semiconductor device of the present invention.
FIG. 8 is a schematic cross-sectional view for explaining a manufacturing method of FLASH EPROM which is another example relating to the manufacturing method of the semiconductor device of the present invention.
FIG. 9 is a schematic cross-sectional view for explaining an example in which a resist pattern thickened using a resist pattern thickening material of the present invention is applied to the manufacture of a magnetic head.
FIG. 10 is a schematic cross-sectional view for explaining another example process (No. 1) in which a resist pattern thickened using the resist pattern thickening material of the present invention is applied to the manufacture of a magnetic head; FIG.
FIG. 11 is a schematic cross-sectional view for explaining another example process (part 2) in which the resist pattern thickened using the resist pattern thickening material of the present invention is applied to the manufacture of a magnetic head; FIG.
FIG. 12 is a schematic cross-sectional view for explaining another example process (No. 3) in which the resist pattern thickened using the resist pattern thickening material of the present invention is applied to the manufacture of a magnetic head; FIG.
FIG. 13 is a schematic cross-sectional view for explaining another example process (No. 4) in which a resist pattern thickened using the resist pattern thickening material of the present invention is applied to the manufacture of a magnetic head; FIG.
FIG. 14 is a schematic cross-sectional view for explaining another example process (No. 5) in which the resist pattern thickened using the resist pattern thickening material of the present invention is applied to the manufacture of a magnetic head; FIG.
FIG. 15 is a schematic cross-sectional view for explaining another example process (No. 6) in which a resist pattern thickened using the resist pattern thickening material of the present invention is applied to the manufacture of a magnetic head; FIG.
FIG. 16 is a plan view showing an example of a magnetic head manufactured in the steps of FIGS.
[Explanation of symbols]
1 Resist pattern thickening material
3 resist pattern
5 Underlayer (base material)
10 resist pattern (present invention)
10a surface layer
10b Inner layer resist pattern
22 Si substrate (semiconductor substrate)
23 Field oxide film
24a First gate insulating film
24b Second gate insulating film
25a First threshold control layer
25b Second threshold control layer
26 Resist film
27 Resist film
28 First polysilicon layer (first conductor film)
28a Floating gate electrode
28b Gate electrode (first polysilicon film)
28c Floating gate electrode
29 resist film
30a Capacitor insulating film
30b Capacitor insulation film
30c capacitor insulating film
30d SiO₂film
31 Second polysilicon layer (second conductor film)
31a Control gate electrode
31b Second polysilicon film
32 resist film
33a First gate part
33b Second gate part
33c Second gate part
34 resist film
35a S / D (source / drain) region layer
35b S / D (source / drain) region layer
36a S / D (source / drain) region layer
36a S / D (source / drain) region layer
37 Interlayer insulation film
38a contact hole
38b contact hole
39a contact hole
39b Contact hole
40a S / D (source / drain) electrodes
40b S / D (source / drain) electrode
41a S / D (source / drain) electrodes
41b S / D (source / drain) electrode
42 Refractory metal film (4th conductor film)
42a refractory metal film (fourth conductor film)
42b refractory metal film (fourth conductor film)
44a First gate part
44b Second gate part
45a S / D (source / drain) region layer
45b S / D (source / drain) region layer
46a S / D (source / drain) region layer
46b S / D (source / drain) region layer
47 Interlayer insulation film
48a contact hole
48b contact hole
49a contact hole
49b Contact hole
50a S / D (source / drain) electrode
50b S / D (source / drain) electrode
51a S / D (source / drain) electrodes
51b S / D (source / drain) electrodes
52a opening
52b opening
53a refractory metal film (third conductor film)
53b refractory metal film (third conductor film)
54 Insulating film
100 interlayer insulation layer
102 resist pattern
104 opening
106 Plating underlayer
108 Thin film conductor (Cu plating film)
110 Thin-film magnetic coil
112 Non-magnetic substrate
114 Gap layer
116 Resin insulation layer
118 resist film
118a resist pattern
120 First spiral pattern
122 Conductive underlayer
124 resist film
126 resist pattern
128 Cu conductor film
130 Thin Film Magnetic Coil
132 Magnetic layer

Claims (4)

Contains a water-soluble or alkali-soluble resin , a crosslinking agent, and at least one cyclic structure compound selected from catechin, delphinidin, resorcin, 1,3-naphthalenediol, and 4-hydroxyadamantane-2-carboxylic acid A resist pattern thickening material characterized by: A resist pattern thickening material comprising a polyvinyl acetal resin containing a polyhydric phenol structure and a cross-linking agent acetalized by 5 mol% or more with an aldehyde having a polyhydric phenol structure. The resist pattern thickening material according to claim 2, wherein the polyvinyl acetal resin containing a polyhydric phenol structure is at least one of a polyvinyl β-resorcin acetal resin and a polyvinyl-2,3-dihydroxybenzacetal resin. The resist pattern thickening material according to any one of claims 1 to 3, comprising a surfactant.

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