JP3652169B2

JP3652169B2 - Substrate developing device

Info

Publication number: JP3652169B2
Application number: JP12397799A
Authority: JP
Inventors: 茂宏後藤; 実信松永
Original assignee: Screen Holdings Co Ltd; Dainippon Screen Manufacturing Co Ltd
Current assignee: Screen Holdings Co Ltd; Dainippon Screen Manufacturing Co Ltd
Priority date: 1999-04-30
Filing date: 1999-04-30
Publication date: 2005-05-25
Anticipated expiration: 2019-04-30
Also published as: JP2000315643A

Description

【０００１】
【発明の属する技術分野】
本発明は、半導体ウエハ、フォトマスク用のガラス基板、液晶表示装置用のガラス基板、光ディスク用の基板など（以下、単に「基板」と称する）の表面に形成されたフォトレジスト膜に現像液を供給して現像処理を施す基板現像装置及び基板現像方法に係り、特に、基板の表面全体に現像液を液盛りして現像処理を施す（いわゆるパドル現像）技術に関する。
【０００２】
【従来の技術】
従来のこの種のパドル現像プロセスでは、現像前に純水リンスノズルから基板上に純水を供給し、その後、現像液ノズルから現像液を基板上に供給して純水を現像液で置換し、基板上に現像液を液盛りした状態で現像処理を行うというプロセスが実施されている。現像液を供給する前に基板上に純水を供給する理由は、現像液と疎水性フォトレジスト膜との密着性が悪いことに起因して現像液中にマイクロバルブが発生し、現像欠陥が生じるのを防止するためである。基板上に純水を供給して基板表面を予め親水性にしておくことにより、上記の現像欠陥の発生を抑制することができる。
【０００３】
【発明が解決しようとする課題】
ところで、最近ではデザインルールの微細化に伴い、ＡｒＦレーザを使う化学増幅型フォトレジスト（以下、「ＡｒＦ系レジスト」と称する）が用いられることがある。このＡｒ系レジストは、Ｉ線やＫｒＦレーザを使う一般的な化学増幅型フォトレジスト（以下、「通常レジスト」と称する）に比べて、現像速度が著しく速いという特質がある。このような現像速度が著しく速いＡｒＦ系レジストに対して、通常レジストで使用される現像液濃度と同じ濃度の現像液を用いると、基板上に液盛りされた現像液の局所的な濃度差の影響によって、基板内の線幅の均一性が損なわれるという問題が生じる。
【０００４】
また、通常レジストのパドル現像においても、焼き付けパターンの種類によっては同じ基板内であっても現像液と反応する領域（面積）に差が生じることがある。例えば、同じ基板内でフォトレジストに小さな窓を開ける箇所と、大きな窓を開ける箇所とが混在している場合、大きな窓を開ける箇所は小さな窓を開ける箇所に比べて現像液と反応する領域が広くなる。このような場合、現像液と反応する領域が広い箇所では現像液の濃度低下が他の箇所に比べて著しくなり、その結果、基板内の線幅の均一性が損なわれるという問題が生じる。
【０００５】
現像液の濃度を比較的に低く設定すると、上記のような問題は解消されるのであるが、現像液の濃度を一律に低下さてしまうと現像時間が長くなり、処理効率が低下するという別異の問題が生じる。
【０００６】
本発明は、このような事情に鑑みてなされたものであって、フォトレジスト膜の特性や焼き付けパターンの種類などに応じた適正濃度の現像液を供給して基板内の線幅の均一性を向上することができる基板現像装置及び基板現像方法を提供することを目的とする。
【０００７】
【課題を解決するための手段】
本発明は、このような目的を達成するために、次のような構成をとる。
すなわち、請求項１に記載の発明は、フォトレジスト膜が形成された基板に親水化処理のための親水化処理液を供給した後に、基板に現像液を供給して基板上に現像液を液盛りし、その状態で現像処理を行う基板現像装置であって、基板を回転可能に保持する回転保持手段と、親水化処理液を供給する親水化処理液供給手段と、原現像液を供給する原現像液供給手段と、親水化処理液供給手段および原現像液供給手段にそれぞれ連通接続され、回転保持手段に保持された基板上に親水化処理液および現像液をその順に供給する単一のノズルと、親水化処理液および原現像液のうちの少なくともいずれか一方の流量を調節する流量調節手段と、親水化処理過程では少なくとも親水化処理液をノズルに送り、現像処理過程では親水化処理液と原現像液とを混合して所定濃度の現像液がノズルから吐出されるように、流量調節手段を操作する制御手段とを備え、制御手段は、現像処理過程で、基板に現像液を供給し、その後に回転保持手段を駆動して基板を一時的に回転させることにより基板上の現像液を一旦振り切るという、現像液の供給と振り切りとを少なくとも１回行わせる現像液の途中振り切り過程を経た後に、ノズルから供給される新たな現像液を基板上に液盛りし、さらに、前記現像液の途中振り切り過程で基板上の現像液を一旦振り切る期間においては、常に親水化処理液が基板に供給されるように流量調節手段を操作するものである。
【０００８】
請求項２に記載の発明は、請求項１に記載の基板現像装置において、制御手段はさらに、前記現像液の途中振り切り過程で現像液を基板に供給する期間は、現像液を基板上に液盛りする期間に比べて短くなるように制御するものである。
【０００９】
請求項３に記載の発明は、請求項１または請求項２に記載の基板現像装置において、制御手段はさらに、現像処理過程の始めには低濃度の現像液が基板に供給され、続いて基板に供給される現像液の濃度が次第に高められ、最終的には目標濃度の現像液が基板に供給されるように、流量調節手段を操作するものである。
【００１０】
請求項４に記載の発明は、請求項１〜３のいずれかに記載の基板現像装置において、親水化処理液供給手段および原現像液供給手段が連通接続するノズル側の接続部位に、逆止弁をそれぞれ設けたものである。
【００１４】
さらに、本明細書は次のような課題解決手段を開示している。
（１）フォトレジスト膜が形成された基板に現像液を液盛りして現像処理を行う基板現像方法において、基板に現像液を供給する過程の始めは低濃度の現像液を供給し、続いて基板に供給する現像液の濃度を次第に高め、最終的には目標濃度の現像液を基板に供給して基板に現像液を液盛りすることを特徴とする基板現像方法。
【００１５】
（作用・効果）
現像処理過程の最初から目標濃度の現像液を基板に供給すると、フォトレジスト膜に対する化学的なインパクトが強くなって現像ムラを発生しやすい。この傾向は、特に現像速度の速い化学増幅型レジストの場合に顕著である。
そこで、本発明では基板に現像液を供給する際に、最初は低濃度の現像液を供給してフォトレジスト膜に対する化学的インパクトを緩和し、続いて徐々に現像液の濃度を高め、最終的には目標濃度の現像液を基板上に液盛りして現像するようにしている。
このようにすれば、基板内の線幅の均一性が向上するとともに、低濃度の現像液だけを使用する場合に比べて、現像処理の効率も向上する。
なお、本発明において現像液を基板上に供給するノズルとしては、濃度調整された現像液を吐出する単一のノズルを使用するのが好ましいが、各々流量調整された純水と原現像液とを個別に基板上に吐出する２つのノズル、あるいは純水用と原現像液用の２つの吐出孔をもつ単一のノズルを用いることも可能である。
【００１６】
（２）フォトレジスト膜が形成された基板に現像液を液盛りして現像処理を行う基板現像方法において、現像処理過程で基板上に液盛りされた現像液を一旦振り切り、その後に新たな現像液を供給して基板上に現像液を液盛りするという、現像液の振り切りと再度の液盛りとを少なくとも１回行うことを特徴とする基板現像方法。
【００１７】
（作用・効果）
単に現像液を基板に液盛りして現像処理を行う従来手法によると、焼き付けパターンの種類によっては、基板内で現像液と反応する領域が広い箇所と、反応する領域が狭い箇所とが生じ、その結果として、液盛りされた現像液に濃度ムラが発生し、線幅の均一性を阻害する。
本発明によれば、現像処理の過程で現像液を一旦振り切り、その後、新たな現像液を供給して液盛りしているので、現像液の濃度ムラを最小限度に抑えて、線幅の均一性を向上することができる。
なお、本発明においても上記（１）と同様にノズルの個数や形態は限定されない。
【００１８】
（３）上記（２）に記載の基板現像方法において、基板上の現像液を振り切る際に、基板上に洗浄液を供給して基板表面を洗浄する基板現像方法。
【００１９】
（作用・効果）
パドル現像処理では、現像液とフォトレジスト膜との反応が進むにつれて、基板上に液盛りされた現像液にレジスト滓が混ざってくる。このレジスト滓は均一な現像処理を行う上で弊害になる。
そこで（３）の発明によれば、現像液を振り切る際に洗浄液（例えば、純水）を供給して基板表面を洗浄するので、現像液中に混在しているレジスト滓が基板表面から洗い流され、その結果、一層均一な現像処理を行うことができる。
【００２０】
【作用】
請求項１に記載の発明の作用は次のとおりである。
処理対象である基板が回転保持手段に保持されると、親水化処理液供給手段からノズルへ親水化処理液が送られ、基板上へ親水化処理液が供給される。基板表面の親水化処理が終わると、制御手段は流量調節手段を操作することにより、親水化処理液および原現像液のうちの少なくともいずれか一方の流量を調節する。少なくとも一方が流量調節された親水化処理液と原現像液とが単一のノズルに送られることにより、親水化処理液と原現像液とが混合してノズルから基板へ所定濃度の現像液が供給される。その結果、基板はフォトレジスト膜の特性や焼き付けパターンの違いなどに応じた適正濃度の現像液で現像処理を受ける。
さらに、現像処理過程で基板上の現像液が一旦振り切られて、その後に新たな現像液が基板上に液盛りされて現像処理が行われるので、同じ基板内で現像液と反応する領域に差があるために現像液に濃度のばらつきが生じても、その現像液が振り切られて新たな現像液が液盛りされることにより、現像液の濃度のばらつきが解消される。
さらに、現像液の途中振り切り過程で基板上の現像液を一旦振り切る期間においては、常に親水化処理液を基板に供給する。
【００２１】
請求項２に記載の発明によれば、現像液の途中振り切り過程で現像液を基板に供給する期間は、現像液を基板上に液盛りする期間に比べて短い。
【００２２】
請求項３に記載の発明によれば、現像処理過程の始めには低濃度の現像液が基板に供給され、続いて基板に供給される現像液の濃度が次第に高められ、最終的には目標濃度の現像液が基板に供給されるように現像液の濃度が制御されるので、現像速度の速いフォトレジストであっても線幅の均一性が損なわれることなく、しかも比較的に短時間で現像処理を行うことができる。
【００２３】
請求項４に記載の発明によれば、親水化処理液供給手段および原現像液供給手段が連通接続するノズル側の接続部位に、逆止弁をそれぞれ設けたので、親水化処理液の供給から現像液の供給へ切り換える場合や、あるいは現像液の供給から親水化処理液（この場合、親水化処理液は洗浄液として作用する）の供給へ切り換える場合に、両液が不必要に混ざり合う期間が短くなる。
【００２７】
【発明の実施の形態】
以下、図面を参照して本発明の実施例を説明する。
＜第１実施例＞
図１は本発明に係る基板現像装置の第１実施例の概略構成を示した図である。この基板現像装置は、半導体ウエハなどの基板Ｗを水平姿勢で吸着保持するスピンチャック１を備えている。スピンチャック１はモータ２の出力軸に連結されている。スピンチャック１およびモータ２は本発明における回転保持手段に相当する。なお、回転保持手段は上記の例に限らず、例えば回転板に立設された複数本のピンで基板Ｗの端縁を保持するようなものでもよい。スピンチャック１の周囲には、親水化処理や現像処理などのときに基板Ｗから振り切られた純水や現像液を回収するための図示しないカップが設けられている。
【００２８】
スピンチャック１の傍らには親水化処理液としての純水や現像液を基板Ｗ上に供給するための単一のノズル３が配設されている。ノズル３の下面にはスリット状の吐出孔３ａが形成されている。ノズル３はモータ４およびエアーシリンダ５によって旋回および昇降駆動されるアーム６に片持ち支持されている。これら駆動機構によって、処理時にはノズル３が基板Ｗに近接して基板Ｗの半径方向に移動し、待機時にはカップの傍らにある図示しない待機ポット内に納められるようになっている。
【００２９】
ノズル３の一方の側面には原現像液（本明細書では親水化処理液で希釈されていない現像液をいう）の供給源からノズル３へ原現像液を送る送液管７の末端が分岐して連通接続されている。また、ノズル３の他方の側面には純水供給源からノズル３へ親水化処理液としての例えば純水を送る送液管８の末端が分岐して連通接続されている。原現像液の供給源（通常は原現像液を収容した容器などであって、本装置内に設置される）および送液管７は、本発明における原現像液供給手段に相当する。また、純水供給源および送液管８は、本発明における親水化処理液供給手段に相当する。ただし、通常、純水の供給源はこの種の基板現像装置が設置されるクリーンルーム内に常備された設備を使用するので、このような場合は送液管８が本発明における親水化処理液供給手段に相当する。
【００３０】
原現像液用の送液管７には流量調節弁９および開閉弁１０が設けられている。また、純水用の送液管８には流量調節弁１１および開閉弁１２が設けられている。流量調節弁９，１１および開閉弁１０，１２は、コンピュータ機器で構成された制御部１３によって操作される。また、制御部１３は上述したスピンチャック１の駆動用モータ２、ノズル３の旋回駆動用モータ４、ノズル３の昇降駆動用エアーシリンダ５などをシーケンス制御する。上述した流量調節弁９，１１は本発明における流量調節手段に、制御部１３は本発明における制御手段に、それぞれ相当する。
【００３１】
原現像液用の送液管７および純水用の送液管８がそれぞれ分岐して連通接続するノズル３の各接続部位には、図２に示すような逆止弁１４が内蔵されている。仮にこのような逆止弁１４が無い場合、原現像液側の開閉弁１０を閉じ、純水側の開閉弁１２を開放して、ノズル３から純水のみを基板Ｗへ供給する場合に、開閉弁１０から下手側の送液管７に残留している原現像液が僅かずつではあるが、ノズル３内を流通している純水に長期にわたって引き込まれて、純水に原現像液が不測に混入するという不都合が生じる。本実施例では、各送液管７，８の接続部位に逆止弁１４をそれぞれ内蔵しているので、上述したような両液の混入は液切換時の一瞬だけで、液切り換えのレスポンスが短くなり、現像処理の品質を高めることができる。
【００３２】
次に、上述した構成を備えた第１実施例装置を用いた現像処理の手順を図３を参照して説明する。
ステップＳ１：純水プリウェット
処理対象である基板Ｗがスピンチャック１に吸着保持されると、スピンチャック１が回転する。このときの回転速度は、４００〜３０００ｒｐｍ程度の比較的に高速の回転速度に設定される。続いて待機位置にあったノズル３が基板Ｗの傍らに移動する。そして、純水を吐出させながらノズル３が、回転中の基板Ｗのエッジ部から回転中心部付近まで移動することにより、基板Ｗに純水を供給する。プリウエット時間は基板表面のフォトレジスト膜の撥水性に応じて決められ、撥水性の高いフォトレジスト膜程長い時間に設定されるが、通常は１０秒程度である。
【００３３】
ステップＳ２：純水パドル形成
基板Ｗの回転速度を落として基板Ｗ上に純水を液盛りする。純水の表面張力との関係で、減速後の回転数は１５０ｒｐｍ以下が好ましい。現像液の供給前に純水パドルを形成するのは、所定濃度の現像液を供給したときに、現像液が純水パドルと混合してその濃度が一時的に低下するので、その方がフォトレジスト膜に対する化学的インパクトが和らぎ、現像処理のムラを抑制する上で好ましいからである。
【００３４】
ステップＳ３₁：現像液の置換（濃度調整された現像液を供給）
処理対象である基板Ｗに形成されたフォトレジスト膜の特性や焼き付けパターンの種類などに応じて、制御部１３は流量調節弁９および１１を操作し、原現像液と純水とが各々所定流量となるようにする。流量調節された原現像液と純水とは送液管７および８を介してノズル３に送られる。ノズル３に送られた原現像液と純水とはノズル３内で混ざり合い、所定濃度の現像液となって吐出される。
【００３５】
純水パドルが形成された基板Ｗに所定濃度の現像液を供給されると、純水パドルが現像液で置換される。このとき、ノズルから吐出された現像液が基板上で滞留するのを防止するために、基板Ｗを１５０ｒｐｍ以上で回転させるのが好ましい。ただし、ノズル３を例えば基板Ｗの中央部からエッジ部へ移動させながら現像液を吐出する場合には、現像液と純水との置換を均一に行うことができるので、基板Ｗを低速回転させてもよい。
【００３６】
また、上記のようにノズル３を移動させて現像液を吐出する場合に、ノズル３が基板Ｗのエッジ部から外れた位置にまで移動してから現像液を停止するようにすれば、ノズル３から現像液のボタ落ちが発生しても基板Ｗ上に落ちないので、現像液のボタ落ちによる現像液の濃度不均一の発生を抑制することができる。
【００３７】
ステップＳ４₁：現像液パドル形成
現像液への置換が終了すると、制御部３は開閉弁１０および１２を閉じて原現像液および純水の供給を停止させるとともに、基板Ｗの回転を停止させて基板Ｗ上に現像液のパドルを形成する。このときの基板Ｗの減速は徐々に行う（例えば、１０００ｒｐｍ／ｓｅｃ以下）のが好ましい。回転中の基板Ｗのエッジ部では、現像液の表面張力と遠心力との釣り合いによって現像液パドルが形成されているので、減速加速度が大きい場合、この釣り合いが急激に破れて基板Ｗのエッジ部から中心部へ向かう現像液の波面が生じて現像液が基板中心部へ移動する。現像液の中心部への移動に伴って、現像処理過程でエッジ部に発生したレジスト滓も基板中心部へ移動し、基板中心部にレジスト滓が集まる。このようにレジスト滓が基板中心部に集まると、基板上の現像液の濃度ムラを引き起こす要因になるので、上記のように基板Ｗの減速を徐々に行うのが好ましい。
【００３８】
ステップＳ５：洗浄
所定時間のバドル現像が終わると、基板Ｗを回転させて基板Ｗ上の現像液を振り切るとともに、開閉弁１０を開放して基板Ｗに純水を供給し、基板Ｗ上の現像液を純水で置換・洗浄する。
【００３９】
ステップＳ６：乾燥
洗浄処理が終わると、純水供給を止めるとともに、基板Ｗを高速回転させて基板Ｗを乾燥させる。
【００４０】
以上のように第１実施例によれば、処理対象である基板Ｗに形成されたフォトレジスト膜の特性や焼き付けパターンの種類に応じて、適正濃度の現像液を供給してパドル現像を行っているので、基板内の線幅の均一性を向上することができる。また、単一のノズル３を用いて親水化処理と現像処理とを行っているので、個別のノズルを用いて各処理を行う場合と比べて、ノズルの移動サイクルが少なくなり、現像処理の効率が上がるとともに、装置のシーケンス制御も簡素化することができる。
【００４１】
＜第２実施例＞
第１実施例では、現像処理過程の最初から一定濃度に調整された現像液を基板Ｗに供給するようにしたが、本実施例では、現像処理過程の始めには低濃度の現像液が基板に供給され、続いて基板に供給される現像液の濃度が次第に高められ、最終的には目標濃度の現像液が基板に供給されるように、制御部３が流量調節弁９および１１を操作している。
なお、基板現像装置の概略構成およびノズル構成は図１および図２に示した第１実施例のものと同様であるので、ここでの説明は省略する。
【００４２】
以下、図４のタイムチャートを参照して本実施例の現像処理の手順を説明する。
親水化処理過程および洗浄・乾燥処理は第１実施例のステップＳ１，Ｓ２，Ｓ５，Ｓ６で説明したと同様であるので、ここでは現像処理過程（現像液の置換ステップＳ３₂および現像液パドル形成ステップＳ４₂）について説明する。
【００４３】
ステップＳ３₂：現像液への置換（現像液濃度を次第に上げる）
純水パドルが形成された基板Ｗに現像液を供給して、純水パドルを現像液で置換する過程において、制御部３は純水流量および原現像液流量を図４に示すように制御する。すなわち、現像液の置換過程の期間Ｔ（Ｔは通常１〜１０ｓｅｃ）にわたり、原現像液の流量を徐々に増加させて最終的には所定流量にする一方、純水の流量を徐々に減少させて最終的には所定流量にする。その結果、ノズル３から基板Ｗへ供給される現像液の濃度は、図４に示すように、始めは低濃度の現像液が基板に供給され、次第に現像液の濃度が高められ、最終的には目標濃度の現像液が基板に供給される。
【００４４】
ステップＳ４₂：現像液パドル形成
基板Ｗに供給される現像液の濃度が目標濃度に達すると（期間Ｔの経過の後）、第１実施例の場合と同様に基板Ｗの回転を減速して、基板Ｗに現像液のパドルを形成する。処理条件等は第１実施例と同様であるので、その説明は省略する。
【００４５】
本実施例によれば、基板Ｗへ供給される現像液の濃度が徐々に高められるので、基板内で現像液の濃度ムラが発生しにくく、反応速度の速いフォトレジスト膜であっても均一に現像処理を行うことができる。また、本実施例によれば、親水化処理過程で基板上に純水パドルを必ずしも形成しておかなくてもよい。
【００４６】
＜第３実施例＞
図５は第３実施例の現像処理過程（現像液の置換ステップＳ３₃および現像液パドル形成ステップＳ４₃）のタイムチャートを示している。親水化処理過程および洗浄・乾燥処理は図４に示した第２実施例のものと同様であるので、図示説明を省略する。
【００４７】
本実施例の特徴は、現像液置換過程で基板Ｗに供給された現像液を一旦振り切り、新たな現像液を再び供給して現像液パドルを形成することにある。以下、ステップＳ３₃，Ｓ４₃を具体的に説明する。
【００４８】
ステップＳ３₃：現像液への置換（現像液の途中振り切り）
制御部１３は、現像液への置換が始まってからｔ₁期間の間、基板Ｗを低速回転させながら、原現像液流量および純水流量を制御して、基板Ｗへ供給される現像液の濃度を徐々に高めていく。ｔ₁〜ｔ₂期間の間は、基板Ｗを高速回転させて基板Ｗ上の現像液を振り切るとともに、原現像液の供給を停止して純水だけを供給することにより基板Ｗの表面を洗浄する。ｔ₂〜ｔ₃期間の間は、現像液の濃度を徐々に高めながら現像液を基板Ｗへ再び供給する。ｔ₃〜ｔ₄期間の間は、上述したｔ₁〜ｔ₂期間と同様に現像液の供給を停止して基板Ｗ上の現像液を振り切るとともに、基板Ｗを純水で洗浄する。ｔ₄〜ｔ₅期間の間は、上述したｔ₂〜ｔ₃期間と同様に現像液の濃度を徐々に高めながら現像液を基板Ｗへ再び供給する。
【００４９】
ステップＳ４₃：現像液パドル形成
ｔ₄〜ｔ₅期間での現像液供給により、基板Ｗ上へ目標濃度の現像液が供給されると、基板Ｗの回転を減速して、基板Ｗに現像液のパドルを形成する。処理条件等は第１実施例と同様であるので、その説明は省略する。
【００５０】
本実施例によれば、基板Ｗへ供給される現像液の濃度を徐々に高めているので、第２実施例と同様に均一な現像処理を行うことができる。また、現像液の供給過程で、基板上の現像液を一旦振り切り、その後で新たな現像液を供給するようにしているので、基板上の現像液の濃度ムラの発生を一層抑制することができる。また、現像液の振り切りとともに、基板Ｗを純水洗浄しているので、基板Ｗ上の現像液に混在するレジスト滓が洗い流され、現像処理の品質を一層向上させることができる。
【００５１】
なお、上述した第３実施例は、次のように変形実施することも可能である。
図６は第３実施例の第１変形例の現像処理過程のタイムチャートを示している。この例では、０〜ｔ₁、ｔ₂〜ｔ₃、ｔ₄〜ｔ₅の各期間内は一定濃度の現像液が供給されるが、上記各期間の相互間では徐々に現像液の濃度を高めている。また、ｔ₁〜ｔ₂およびｔ₃〜ｔ₄期間では基板Ｗ上の現像液を振り切るとともに、基板Ｗを純水洗浄している。このような変形例によっても、上述した第３実施例と同様に現像液の濃度ムラの発生を抑制することができるとともに、現像液中のレジスト滓を除去することが可能である。
【００５２】
図７は第３実施例の第２変形例の現像処理過程のタイムチャートを示している。この例では、０〜ｔ₁、ｔ₂〜ｔ₃、ｔ₄〜ｔ₅の各期間にわたり、フォトレジスト膜の特性やレジストパターンに応じて適宜に濃度調整された一定濃度の現像液を供給している。また、ｔ₁〜ｔ₂およびｔ₃〜ｔ₄期間では基板Ｗ上の現像液を振り切るとともに、基板Ｗを純水洗浄している。このような変形例によっても、現像液のパドル形成前に基板Ｗの現像液が一旦振り切られて、再び新たな現像液が供給されるので、現像液の濃度ムラの発生を抑制することができるとともに、現像液中のレジスト滓を除去することが可能である。
【００５３】
さらに、第３実施例およびその変形例では、現像液パドル形成前に基板Ｗ上の現像液を２回振り切るようにしたが、振り切り回数はこれに限らず任意に設定可能である。
【００５４】
本発明は、上述した各実施例のものに限らず、次のように変形実施することができる。
（１）第１実施例では、現像液の濃度調整のために原現像液用の流量調節弁９と純水用の流量調節弁１１とを設けたが、一方の流量を一定にしておき、他方の流量だけを流量調節弁で調節するようにして、現像液の濃度調整を行ってもよい。
【００５５】
（２）第１実施例（図２）では、ノズル３に逆止弁１４を内蔵させた構造を例示したが、これは図８に示すように、原現像液用の送液管７および純水用の送液管８が連通接続するノズル３の側面の接続部位のそれぞれに、開閉弁１０，１２（図１参照）を取り付けるようにしてもよい。このような構成によっても、ノズル３から開閉弁１０，１２までの送液流路を最小長さに抑えることができるので、原現像液と純水との不所望な混合を避けて、処理液の切り換えのレスポンスを速めることができる。
【００５６】
（３）実施例では親水化処理液として純水を使ったが、親水化処理液として希釈現像液を使ってもよい。このような希釈現像液は、例えば図１の例では、親水化処理過程で純水に僅かな原現像液を混合させることにより、容易に生成することができる。
【００５７】
（４）実施例ではスリット形状の吐出孔を備えたノズルを例示したが、本発明はこれに限らず、例えば円形状の吐出孔を備えたノズルなど、種々の形態のノズルを用いることができる。
【００５８】
（５）図１に示した実施例ではノズル３に原現像液用および純水用の各々１系統の送液管７，８を連通接続したが、本発明はこれに限らず、例えば濃度の異なる２系統の原現像液用の送液管をノズルに連通接続したり、あるいは温調の有無に応じた２系統の純水用の送液管をノズル３に連通接続することも可能である。
【００５９】
【発明の効果】
以上の説明から明らかなように、本発明によれば次の効果を奏する。
請求項１に記載の発明によれば、フォトレジスト膜の特性や焼き付けパターンの種類などに応じた適正濃度の現像液を供給して現像処理を行うことができるので、基板内の線幅の均一性を向上することができる。
また、請求項１に記載の発明によれば、単一のノズルによって親水化処理液の供給と現像液の供給とを行っているので、個別のノズルを使って親水化処理と現像処理とを行っていた従来装置に比べて、ノズルの移動サイクルが少なくなり、それだけ現像処理を効率よく行うことができるとともに、装置のシーケンス制御を簡素化することができる。
さらに、現像処理過程で基板上の現像液を一旦振り切り、その後で新たな現像液を液盛りして現像処理を行っているので、液盛りされた現像液の濃度のバラツキを最小限に抑えることができ、濃度のバラツキに起因した現像処理のムラを防止することができる。
さらに、現像液の途中振り切り過程で基板上の現像液を一旦振り切る期間においては、常に親水化処理液を基板に供給する。
【００６０】
請求項２に記載の発明によれば、現像液の途中振り切り過程で現像液を基板に供給する期間は、現像液を基板上に液盛りする期間に比べて短い。
【００６１】
請求項３に記載の発明によれば、最初は低濃度の現像液を使って現像処理を行い、次第に現像液の濃度を高め、最終的には目標濃度の現像液で現像処理を行うようにしているので、現像速度の速いフォトレジスト膜であっても線幅の均一性が損なわれることなく、しかも比較的に短時間で現像処理を行うことができる。
【００６２】
請求項４に記載の発明によれば、親水化処理液と原現像液とが不所望に混ざり合う期間が短くなり、親水化処理液から現像液、あるいは現像液から親水化処理液への切り換えを迅速に行うことができるので、現像処理の品質を高めることができる。
【図面の簡単な説明】
【図１】本発明に係る基板現像装置の第１実施例の要部構成を示した図である。
【図２】ノズルの構造を示した断面図である。
【図３】第１実施例の動作順序を示したフローチャートである。
【図４】第２実施例の現像処理過程を示したタイムチャートである。
【図５】第３実施例の現像処理過程を示したタイムチャートである。
【図６】第３実施例の変形例のタイムチャートである。
【図７】さらに別の変形例のタイムチャートである。
【図８】ノズルに開閉弁を取り付けた例を示す断面図である。
【符号の説明】
１…スピンチャック
２…モータ
３…ノズル
７…原現像液用の送液管
８…純水用の送液管
９…原現像液用の流量調節弁
１０…原現像液用の開閉弁
１１…純水（親水化処理液）用の流量調節弁
１２…純水用の開閉弁
１３…制御部
１４…逆止弁[0001]
BACKGROUND OF THE INVENTION
  In the present invention, a developer is applied to a photoresist film formed on the surface of a semiconductor wafer, a glass substrate for a photomask, a glass substrate for a liquid crystal display device, a substrate for an optical disk (hereinafter simply referred to as “substrate”). Substrate developing device for supplying and developing processingAnd substrate developing methodIn particular, the present invention relates to a technique in which a developing solution is deposited on the entire surface of a substrate to perform development processing (so-called paddle development).
[0002]
[Prior art]
  In this type of conventional paddle development process, pure water is supplied onto the substrate from the pure water rinse nozzle before development, and then the developer is supplied onto the substrate from the developer nozzle to replace the pure water with the developer. In addition, a process is performed in which a developing process is performed in a state where a developing solution is accumulated on a substrate. The reason for supplying pure water on the substrate before supplying the developer is that the adhesion between the developer and the hydrophobic photoresist film is poor and microvalves are generated in the developer, resulting in development defects. This is to prevent the occurrence. By supplying pure water onto the substrate to make the substrate surface hydrophilic in advance, the development defects can be suppressed.
[0003]
[Problems to be solved by the invention]
  Recently, with the miniaturization of design rules, a chemically amplified photoresist using an ArF laser (hereinafter referred to as “ArF resist”) may be used. This Ar-based resist has a characteristic that its developing speed is remarkably higher than that of a general chemical amplification type photoresist (hereinafter referred to as “normal resist”) using an I-line or KrF laser. When a developing solution having the same concentration as the developing solution used in a normal resist is used for such an ArF resist having a remarkably fast developing speed, the local concentration difference of the developing solution on the substrate is reduced. Due to the influence, there arises a problem that the uniformity of the line width in the substrate is impaired.
[0004]
  Further, even in the paddle development of a normal resist, there may be a difference in the area (area) that reacts with the developer even in the same substrate depending on the type of printing pattern. For example, if there are a mixture of locations where a small window is opened and a location where a large window is opened in the same substrate, the region where the large window is opened has a region that reacts with the developer compared to the location where the small window is opened. Become wider. In such a case, the density of the developing solution is significantly reduced in a portion where the region reacting with the developing solution is wide as compared with other portions, and as a result, there arises a problem that the uniformity of the line width in the substrate is impaired.
[0005]
  If the developer concentration is set relatively low, the above problems can be solved. However, if the developer concentration is lowered uniformly, the development time becomes longer and the processing efficiency is lowered. Problem arises.
[0006]
  The present invention has been made in view of such circumstances, and by supplying a developer having an appropriate concentration according to the characteristics of the photoresist film and the type of the baking pattern, the uniformity of the line width in the substrate is improved. Substrate developing device that can be improvedAnd substrate developing methodThe purpose is to provide.
[0007]
[Means for Solving the Problems]
  In order to achieve such an object, the present invention has the following configuration.
  That is, according to the first aspect of the present invention, after supplying a hydrophilic treatment liquid for hydrophilic treatment to a substrate on which a photoresist film is formed, the developer is supplied to the substrate and the developer is applied onto the substrate. A substrate developing apparatus that performs a developing process in the state, and includes a rotation holding unit that rotatably holds the substrate, a hydrophilic treatment liquid supply unit that supplies a hydrophilic treatment liquid, and a raw developer. A single developer liquid supply means, a hydrophilization treatment liquid supply means and an original developer supply means are connected in communication with each other, and a hydrophilic treatment liquid and a developer are supplied in that order onto the substrate held by the rotation holding means. A nozzle, a flow rate adjusting means for adjusting the flow rate of at least one of the hydrophilic treatment liquid and the original developer, and at least the hydrophilic treatment liquid is sent to the nozzle during the hydrophilic treatment process, and the hydrophilic treatment is performed during the development process. Liquid and original And a control means for operating the flow rate adjusting means so that the developer of a predetermined concentration is discharged from the nozzle by mixing with the liquid, and the control means supplies the developer to the substrate during the development process, and then After passing through the process of shaking off the developer at least once, the developer is supplied and shaken off once by temporarily turning off the developer on the substrate by driving the rotation holding means to temporarily rotate the substrate, New developer supplied from the nozzle is deposited on the substrate.Further, the flow rate adjusting means is operated so that the hydrophilization liquid is always supplied to the substrate during the period in which the developer on the substrate is once shaken off during the process of shaking off the developer.Is.
[0008]
  According to a second aspect of the present invention, in the substrate developing apparatus according to the first aspect,The control means further controls that the period during which the developer is supplied to the substrate during the process of shaking off the developer is shorter than the period during which the developer is accumulated on the substrate.Is.
[0009]
  The invention described in claim 3 is the substrate developing apparatus according to claim 1 or 2, whereinThe control unit further supplies a low-concentration developer to the substrate at the beginning of the development process, and then gradually increases the concentration of the developer supplied to the substrate. The flow control means to be fed toIs.
[0010]
  The invention according to claim 4 is the substrate developing apparatus according to any one of claims 1 to 3,A check valve is provided at each of the nozzle side connection portions where the hydrophilic treatment solution supply means and the original developer supply means communicate with each other.Is.
[0014]
  Furthermore, the present specification discloses the following means for solving problems.
  (1) In a substrate developing method in which a developing solution is deposited on a substrate on which a photoresist film is formed and a developing process is performed, a low concentration developing solution is supplied at the beginning of the process of supplying the developing solution to the substrate. A substrate developing method comprising gradually increasing the concentration of a developing solution supplied to a substrate, finally supplying a developing solution having a target concentration to the substrate, and depositing the developing solution on the substrate.
[0015]
  (Action / Effect)
  When a developing solution having a target concentration is supplied to the substrate from the beginning of the developing process, the chemical impact on the photoresist film is increased and development unevenness is likely to occur. This tendency is remarkable particularly in the case of a chemically amplified resist having a high development rate.
  Therefore, in the present invention, when supplying the developer to the substrate, first, a low-concentration developer is supplied to alleviate the chemical impact on the photoresist film, and then the concentration of the developer is gradually increased. In this case, a developing solution having a target concentration is accumulated on the substrate for development.
  In this way, the uniformity of the line width in the substrate is improved, and the efficiency of the development process is improved as compared with the case where only a low-concentration developer is used.
  In the present invention, as the nozzle for supplying the developer onto the substrate, it is preferable to use a single nozzle that discharges the developer whose concentration has been adjusted. It is also possible to use two nozzles that individually discharge the liquid on the substrate, or a single nozzle having two discharge holes for pure water and raw developer.
[0016]
  (2) In a substrate development method in which a developing solution is deposited on a substrate on which a photoresist film is formed, and the developing process is performed, the developing solution accumulated on the substrate in the course of the developing process is once shaken off, and then a new development is performed. A method for developing a substrate, comprising: supplying the solution and depositing the developer on the substrate, wherein the developer is shaken off and re-filled at least once.
[0017]
  (Action / Effect)
  According to the conventional method of simply depositing the developer on the substrate and performing the development process, depending on the type of baking pattern, there are a wide area that reacts with the developer and a narrow area that reacts in the substrate, As a result, density unevenness occurs in the accumulated developer, and the line width uniformity is hindered.
  According to the present invention, the developer is once shaken off in the course of the development process, and then a new developer is supplied and accumulated, so that the density unevenness of the developer is minimized and the line width is uniform. Can be improved.
  In the present invention, the number and form of the nozzles are not limited as in (1) above.
[0018]
  (3) The substrate developing method according to (2), wherein when the developer on the substrate is shaken off, the substrate surface is cleaned by supplying a cleaning solution onto the substrate.
[0019]
  (Action / Effect)
  In the paddle development process, as the reaction between the developer and the photoresist film proceeds, the resist soot is mixed with the developer accumulated on the substrate. This resist film becomes a harmful effect in performing uniform development processing.
  Therefore, according to the invention of (3), when the developer is shaken off, the substrate surface is cleaned by supplying a cleaning solution (for example, pure water), so that the resist soot mixed in the developer is washed away from the substrate surface. As a result, a more uniform development process can be performed.
[0020]
[Action]
  The operation of the first aspect of the invention is as follows.
  When the substrate to be processed is held by the rotation holding means, the hydrophilic treatment liquid is sent from the hydrophilic treatment liquid supply means to the nozzle, and the hydrophilic treatment liquid is supplied onto the substrate. When the hydrophilic treatment on the substrate surface is completed, the control means operates the flow rate adjusting means to adjust the flow rate of at least one of the hydrophilic treatment liquid and the original developer. When the hydrophilization treatment liquid and the original developer whose flow rate has been adjusted at least one is sent to a single nozzle, the hydrophilic treatment liquid and the original developer are mixed, and the developer of a predetermined concentration is transferred from the nozzle to the substrate. Supplied. As a result, the substrate is subjected to development processing with a developer having an appropriate concentration according to the characteristics of the photoresist film and the difference in the baking pattern.
  Furthermore, the developing solution on the substrate is once shaken off during the developing process, and then a new developing solution is deposited on the substrate and the developing process is performed. Therefore, there is a difference in the region that reacts with the developing solution in the same substrate. For this reason, even if the developer has a variation in density, the developer is shaken off and a new developer is added, thereby eliminating the variation in the concentration of the developer.
Further, in the period in which the developer on the substrate is once shaken off during the course of shaking off the developer, the hydrophilic treatment solution is always supplied to the substrate.
[0021]
  According to invention of Claim 2,The period during which the developer is supplied to the substrate during the process of shaking off the developer is shorter than the period during which the developer is accumulated on the substrate.
[0022]
  According to invention of Claim 3,At the beginning of the development process, a low-concentration developer is supplied to the substrate, and subsequently the concentration of the developer supplied to the substrate is gradually increased, so that the target-concentration developer is finally supplied to the substrate. In addition, since the concentration of the developer is controlled, even with a photoresist having a high development speed, the line width uniformity is not impaired, and the development process can be performed in a relatively short time.
[0023]
  According to invention of Claim 4,Since a check valve is provided at each nozzle-side connection site where the hydrophilic treatment liquid supply means and the original developer supply means communicate with each other, when switching from the supply of the hydrophilic treatment liquid to the supply of the developer, or development When switching from the supply of the liquid to the supply of the hydrophilic treatment liquid (in this case, the hydrophilic treatment liquid acts as a cleaning liquid), the period during which both liquids are unnecessarily mixed is shortened.
[0027]
DETAILED DESCRIPTION OF THE INVENTION
  Embodiments of the present invention will be described below with reference to the drawings.
<First embodiment>
  FIG. 1 is a diagram showing a schematic configuration of a first embodiment of a substrate developing apparatus according to the present invention. The substrate developing apparatus includes a spin chuck 1 that holds a substrate W such as a semiconductor wafer in a horizontal posture. The spin chuck 1 is connected to the output shaft of the motor 2. The spin chuck 1 and the motor 2 correspond to the rotation holding means in the present invention. The rotation holding means is not limited to the above example, and may be one that holds the edge of the substrate W with a plurality of pins erected on the rotating plate, for example. Around the spin chuck 1, a cup (not shown) for collecting pure water and developer that has been shaken off from the substrate W during a hydrophilic treatment or a development treatment is provided.
[0028]
  A single nozzle 3 for supplying pure water or a developing solution as a hydrophilization processing solution onto the substrate W is disposed beside the spin chuck 1. A slit-like discharge hole 3 a is formed on the lower surface of the nozzle 3. The nozzle 3 is cantilevered by an arm 6 that is swiveled and moved up and down by a motor 4 and an air cylinder 5. By these drive mechanisms, the nozzle 3 moves in the radial direction of the substrate W close to the substrate W during processing, and is stored in a standby pot (not shown) beside the cup during standby.
[0029]
  On one side surface of the nozzle 3, the end of a liquid feed pipe 7 that feeds the original developer to the nozzle 3 from a source of the original developer (in this specification, a developer that is not diluted with a hydrophilic treatment solution) is branched. Are connected. Further, the other side of the nozzle 3 is branched and connected to the end of a liquid feed pipe 8 that feeds, for example, pure water as a hydrophilic treatment liquid from the pure water supply source to the nozzle 3. The supply source of the original developer (usually a container containing the original developer, which is installed in the apparatus) and the liquid feeding pipe 7 correspond to the original developer supply means in the present invention. Moreover, the pure water supply source and the liquid feeding pipe 8 correspond to the hydrophilic treatment liquid supply means in the present invention. However, since the supply source of pure water normally uses equipment provided in a clean room in which this type of substrate developing apparatus is installed, in such a case, the liquid feed pipe 8 is used to supply the hydrophilic treatment liquid in the present invention. Corresponds to means.
[0030]
  A flow rate adjusting valve 9 and an opening / closing valve 10 are provided in the liquid feeding pipe 7 for the original developer. The pure water liquid supply pipe 8 is provided with a flow rate adjusting valve 11 and an on-off valve 12. The flow control valves 9 and 11 and the on-off valves 10 and 12 are operated by a control unit 13 configured by computer equipment. Further, the control unit 13 performs sequence control on the drive motor 2 for the spin chuck 1, the turning drive motor 4 for the nozzle 3, the air cylinder 5 for raising and lowering the nozzle 3, and the like. The flow control valves 9 and 11 described above correspond to the flow control means in the present invention, and the control unit 13 corresponds to the control means in the present invention.
[0031]
  A check valve 14 as shown in FIG. 2 is built in each connection portion of the nozzle 3 where the liquid feed pipe 7 for the original developer and the liquid feed pipe 8 for pure water are branched and connected. . If such a check valve 14 is not provided, when the on-off valve 10 on the original developer side is closed, the on-off valve 12 on the pure water side is opened, and only pure water is supplied from the nozzle 3 to the substrate W, Although the original developer remaining in the lower-side liquid supply pipe 7 from the on-off valve 10 is little by little, the original developer is drawn into the pure water flowing through the nozzle 3 over a long period of time, and the original developer is brought into the pure water. The inconvenience of inadvertent mixing occurs. In this embodiment, since the check valve 14 is built in the connection part of each liquid feeding pipe 7 and 8, mixing of both liquids as described above is only for a moment at the time of liquid switching, and the response of liquid switching is It becomes shorter and the quality of development processing can be improved.
[0032]
  Next, a development processing procedure using the first embodiment apparatus having the above-described configuration will be described with reference to FIG.
  Step S1: Pure water pre-wet
  When the substrate W to be processed is attracted and held on the spin chuck 1, the spin chuck 1 rotates. The rotation speed at this time is set to a relatively high rotation speed of about 400 to 3000 rpm. Subsequently, the nozzle 3 located at the standby position moves to the side of the substrate W. Then, the pure water is supplied to the substrate W by the nozzle 3 moving from the edge portion of the rotating substrate W to the vicinity of the rotation center portion while discharging the pure water. The prewetting time is determined according to the water repellency of the photoresist film on the substrate surface, and is set to a longer time as the photoresist film having a higher water repellency, but is usually about 10 seconds.
[0033]
  Step S2: Pure water paddle formation
  The rotation speed of the substrate W is reduced to pour pure water on the substrate W. In view of the surface tension of pure water, the rotational speed after deceleration is preferably 150 rpm or less. The pure water paddle is formed before supplying the developer because when the developer of a predetermined concentration is supplied, the developer is mixed with the pure water paddle and the concentration temporarily decreases. This is because the chemical impact on the resist film is eased, and this is preferable for suppressing unevenness in development processing.
[0034]
  Step S3₁: Developer replacement (Supply density adjusted developer)
  The control unit 13 operates the flow rate adjusting valves 9 and 11 according to the characteristics of the photoresist film formed on the substrate W to be processed, the kind of the baking pattern, etc. To be. The flow-adjusted original developer and pure water are sent to the nozzle 3 via the liquid feeding pipes 7 and 8. The original developer and pure water sent to the nozzle 3 are mixed in the nozzle 3 and discharged as a developer having a predetermined concentration.
[0035]
  When a predetermined concentration of developer is supplied to the substrate W on which the pure water paddle is formed, the pure water paddle is replaced with the developer. At this time, in order to prevent the developer discharged from the nozzle from staying on the substrate, the substrate W is preferably rotated at 150 rpm or more. However, when the developing solution is discharged while moving the nozzle 3 from the central portion of the substrate W to the edge portion, for example, the replacement of the developing solution and pure water can be performed uniformly, so the substrate W is rotated at a low speed. May be.
[0036]
  Further, when the developer is discharged by moving the nozzle 3 as described above, if the developer is stopped after the nozzle 3 has moved to a position off the edge of the substrate W, the nozzle 3 Thus, even if the developer drops off, the developer does not fall on the substrate W, so that it is possible to suppress the occurrence of uneven developer concentration due to the developer dropping off.
[0037]
  Step S4₁: Developer paddle formation
  When the replacement with the developer is completed, the control unit 3 closes the on-off valves 10 and 12 to stop the supply of the original developer and pure water, and also stops the rotation of the substrate W to paddle the developer on the substrate W. Form. At this time, it is preferable to gradually decelerate the substrate W (for example, 1000 rpm / sec or less). Since the developer paddle is formed at the edge portion of the rotating substrate W by the balance between the surface tension of the developer and the centrifugal force, when the deceleration acceleration is large, this balance is abruptly broken and the edge portion of the substrate W is The developer wavefront from the center toward the center is generated, and the developer moves to the center of the substrate. Along with the movement of the developing solution to the central part, the resist soot generated at the edge part during the developing process also moves to the central part of the substrate, and the resist soot collects in the central part of the substrate. If the resist soot collects in the center of the substrate as described above, it causes a density unevenness of the developing solution on the substrate. Therefore, it is preferable to gradually decelerate the substrate W as described above.
[0038]
  Step S5: Cleaning
  When the paddle development for a predetermined time is completed, the substrate W is rotated to shake off the developer on the substrate W, and the open / close valve 10 is opened to supply pure water to the substrate W. The developer on the substrate W is supplied with pure water. Replace and wash with.
[0039]
  Step S6: Drying
  When the cleaning process is finished, the pure water supply is stopped and the substrate W is rotated at a high speed to dry the substrate W.
[0040]
  As described above, according to the first embodiment, depending on the characteristics of the photoresist film formed on the substrate W to be processed and the type of the baking pattern, the developer of the appropriate concentration is supplied to perform the paddle development. Therefore, the uniformity of the line width in the substrate can be improved. Further, since the hydrophilic treatment and the development process are performed using the single nozzle 3, the nozzle movement cycle is reduced as compared with the case where each process is performed using individual nozzles, and the efficiency of the development process is reduced. As a result, the sequence control of the apparatus can be simplified.
[0041]
<Second embodiment>
  In the first embodiment, the developer adjusted to a constant concentration from the beginning of the development process is supplied to the substrate W. However, in this embodiment, the low-concentration developer is applied to the substrate at the beginning of the development process. The control unit 3 operates the flow rate control valves 9 and 11 so that the concentration of the developer supplied to the substrate and subsequently supplied to the substrate is gradually increased, and finally the developer having the target concentration is supplied to the substrate. doing.
  Note that the schematic configuration and nozzle configuration of the substrate developing apparatus are the same as those of the first embodiment shown in FIGS. 1 and 2, and a description thereof will be omitted here.
[0042]
  Hereinafter, the development processing procedure of this embodiment will be described with reference to the time chart of FIG.
  Since the hydrophilization process and the cleaning / drying process are the same as those described in steps S1, S2, S5, and S6 of the first embodiment, the development process (developer replacement step S3) is performed here.₂And developer paddle forming step S4₂).
[0043]
  Step S3₂: Replacement with developer (Slowly increase developer concentration)
  In the process of supplying the developer to the substrate W on which the pure water paddle is formed and replacing the pure water paddle with the developer, the control unit 3 controls the pure water flow rate and the raw developer flow rate as shown in FIG. . That is, over the period T (T is usually 1 to 10 seconds) of the developer replacement process, the flow rate of the original developer is gradually increased to finally reach a predetermined flow rate, while the flow rate of pure water is gradually decreased. Finally, the predetermined flow rate is set. As a result, as shown in FIG. 4, the concentration of the developer supplied from the nozzle 3 to the substrate W is initially supplied with a low-concentration developer, and the developer concentration is gradually increased. Is supplied to the substrate with a developer having a target concentration.
[0044]
  Step S4₂: Developer paddle formation
  When the concentration of the developer supplied to the substrate W reaches the target concentration (after the lapse of the period T), the rotation of the substrate W is decelerated as in the first embodiment, and the developer paddles on the substrate W. Form. Since the processing conditions and the like are the same as those in the first embodiment, the description thereof is omitted.
[0045]
  According to this embodiment, since the concentration of the developer supplied to the substrate W is gradually increased, the concentration unevenness of the developer in the substrate is less likely to occur, and even a photoresist film having a high reaction rate can be evenly formed. Development processing can be performed. Further, according to this embodiment, the pure water paddle does not necessarily have to be formed on the substrate during the hydrophilization process.
[0046]
<Third embodiment>
  FIG. 5 shows the developing process in the third embodiment (developer replacement step S3)._ThreeAnd developer paddle forming step S4_Three) Shows a time chart. The hydrophilization process and the cleaning / drying process are the same as those in the second embodiment shown in FIG.
[0047]
  The feature of this embodiment is that the developer supplied to the substrate W in the developer replacement process is once shaken off, and a new developer is supplied again to form a developer paddle. Hereinafter, step S3_Three, S4_ThreeWill be described in detail.
[0048]
  Step S3_Three: Replacement with developer (shake off the developer halfway)
  The controller 13 starts t after the replacement with the developer starts.₁During the period, the concentration of the developer supplied to the substrate W is gradually increased by controlling the flow rate of the original developer and the flow rate of pure water while rotating the substrate W at a low speed. t₁~ T₂During the period, the surface of the substrate W is cleaned by rotating the substrate W at a high speed to shake off the developer on the substrate W and stopping the supply of the original developer and supplying only pure water. t₂~ T_ThreeDuring the period, the developer is supplied again to the substrate W while gradually increasing the concentration of the developer. t_Three~ T_FourDuring the period, t₁~ T₂Similarly to the period, the supply of the developer is stopped, the developer on the substrate W is shaken off, and the substrate W is washed with pure water. t_Four~ T_FiveDuring the period, t₂~ T_ThreeSimilarly to the period, the developer is supplied again to the substrate W while gradually increasing the concentration of the developer.
[0049]
  Step S4_Three: Developer paddle formation
  t_Four~ T_FiveWhen a developing solution having a target concentration is supplied onto the substrate W by supplying the developing solution in a period, the rotation of the substrate W is decelerated and a paddle of the developing solution is formed on the substrate W. Since the processing conditions and the like are the same as those in the first embodiment, the description thereof is omitted.
[0050]
  According to this embodiment, since the concentration of the developer supplied to the substrate W is gradually increased, a uniform developing process can be performed as in the second embodiment. Further, in the process of supplying the developer, the developer on the substrate is once shaken off and then a new developer is supplied, so that it is possible to further suppress the occurrence of uneven density of the developer on the substrate. . Further, since the substrate W is washed with pure water as the developer is shaken off, the resist soot mixed in the developer on the substrate W is washed away, and the quality of the developing process can be further improved.
[0051]
  The third embodiment described above can be modified as follows.
  FIG. 6 shows a time chart of the developing process in the first modification of the third embodiment. In this example, 0 to t₁, T₂~ T_Three, T_Four~ T_FiveDuring each period, a constant concentration of the developer is supplied, but the concentration of the developer is gradually increased between the above periods. T₁~ T₂And t_Three~ T_FourDuring the period, the developer on the substrate W is shaken off and the substrate W is washed with pure water. Even with such a modification, it is possible to suppress the occurrence of uneven concentration of the developer as in the third embodiment, and it is possible to remove the resist soot in the developer.
[0052]
  FIG. 7 shows a time chart of the developing process of the second modification of the third embodiment. In this example, 0 to t₁, T₂~ T_Three, T_Four~ T_FiveDuring each period, a constant concentration developer whose concentration is appropriately adjusted according to the characteristics of the photoresist film and the resist pattern is supplied. T₁~ T₂And t_Three~ T_FourDuring the period, the developer on the substrate W is shaken off and the substrate W is washed with pure water. Also according to such a modification, the developer on the substrate W is once shaken off and the new developer is supplied again before forming the paddle of the developer, so that it is possible to suppress the occurrence of uneven density of the developer. At the same time, it is possible to remove the resist soot in the developer.
[0053]
  Further, in the third embodiment and its modification, the developer on the substrate W is shaken out twice before forming the developer paddle, but the number of times of shaking is not limited to this and can be arbitrarily set.
[0054]
  The present invention is not limited to the above-described embodiments but can be modified as follows.
  (1) In the first embodiment, the flow rate adjusting valve 9 for the original developer and the flow rate adjusting valve 11 for pure water are provided for adjusting the concentration of the developer, but one flow rate is kept constant, The developer concentration may be adjusted by adjusting only the other flow rate with the flow rate control valve.
[0055]
  (2) In the first embodiment (FIG. 2), the structure in which the check valve 14 is built in the nozzle 3 is illustrated. As shown in FIG. On-off valves 10 and 12 (see FIG. 1) may be attached to each of the connection portions on the side surface of the nozzle 3 to which the water supply pipe 8 is connected in communication. Even with such a configuration, the liquid feed flow path from the nozzle 3 to the on-off valves 10 and 12 can be kept to a minimum length, so that undesired mixing of the original developer and pure water is avoided, and the processing liquid The response of switching can be speeded up.
[0056]
  (3) In the examples, pure water was used as the hydrophilic treatment solution, but a diluted developer may be used as the hydrophilic treatment solution. For example, in the example of FIG. 1, such a diluted developer can be easily generated by mixing a small amount of an original developer with pure water in the process of hydrophilization.
[0057]
  (4) In the embodiment, the nozzle having the slit-shaped discharge hole is exemplified, but the present invention is not limited to this, and various types of nozzles such as a nozzle having a circular discharge hole can be used. .
[0058]
  (5) In the embodiment shown in FIG. 1, the liquid supply pipes 7 and 8 for the raw developer and pure water are connected to the nozzle 3 in communication with each other. However, the present invention is not limited to this. It is also possible to connect two different liquid supply pipes for the original developer to the nozzle, or to connect two liquid supply pipes for pure water according to the presence or absence of temperature control to the nozzle 3. .
[0059]
【The invention's effect】
  As is clear from the above description, the present invention has the following effects.
  According to the first aspect of the present invention, since the developing process can be performed by supplying a developing solution having an appropriate concentration according to the characteristics of the photoresist film and the type of the baking pattern, the line width in the substrate is uniform. Can be improved.
  According to the first aspect of the present invention, since the hydrophilic treatment liquid and the developer are supplied by a single nozzle, the hydrophilic treatment and the development treatment are performed using individual nozzles. Compared with the conventional apparatus that has been used, the number of nozzle movement cycles is reduced, so that the development process can be performed more efficiently, and the sequence control of the apparatus can be simplified.
  In addition, the developer on the substrate is temporarily shaken off during the development process, and after that, the development process is performed by adding a new developer, thereby minimizing variations in the concentration of the accumulated developer. And unevenness in the development process due to density variations can be prevented.
Further, in the period in which the developer on the substrate is once shaken off during the course of shaking off the developer, the hydrophilic treatment solution is always supplied to the substrate.
[0060]
  According to invention of Claim 2,The period during which the developer is supplied to the substrate during the process of shaking off the developer is shorter than the period during which the developer is accumulated on the substrate.
[0061]
  According to invention of Claim 3,At first, development processing is performed using a low-concentration developer, the concentration of the developer is gradually increased, and finally the development processing is performed with a target-concentration developer. However, the development processing can be performed in a relatively short time without impairing the uniformity of the line width.
[0062]
  According to invention of Claim 4,The period during which the hydrophilic treatment solution and the original developer are undesirably mixed is shortened, and the switching from the hydrophilic treatment solution to the developer or from the developer to the hydrophilic treatment solution can be performed quickly. Can improve the quality.
[Brief description of the drawings]
FIG. 1 is a diagram showing a main configuration of a first embodiment of a substrate developing apparatus according to the present invention.
FIG. 2 is a sectional view showing the structure of a nozzle.
FIG. 3 is a flowchart showing an operation sequence of the first embodiment.
FIG. 4 is a time chart showing a developing process of a second embodiment.
FIG. 5 is a time chart showing a developing process of a third embodiment.
FIG. 6 is a time chart of a modification of the third embodiment.
FIG. 7 is a time chart of still another modified example.
FIG. 8 is a cross-sectional view showing an example in which an on-off valve is attached to a nozzle.
[Explanation of symbols]
  1 ... Spin chuck
  2 ... Motor
  3 ... Nozzle
  7 ... Feed pipe for raw developer
  8 ... pipe for pure water
  9 ... Flow control valve for raw developer
10: Open / close valve for the original developer
11 ... Flow control valve for pure water (hydrophilic treatment liquid)
12 ... Open / close valve for pure water
13. Control unit
14 ... Check valve

Claims

A substrate on which a hydrophilization treatment liquid for hydrophilization treatment is supplied to the substrate on which the photoresist film is formed, and then the developer is supplied to the substrate to deposit the developer on the substrate, and the development processing is performed in that state. A developing device,
Rotation holding means for holding the substrate rotatably;
A hydrophilic treatment liquid supply means for supplying the hydrophilic treatment liquid;
An original developer supply means for supplying the original developer;
A single nozzle that is connected to the hydrophilic treatment liquid supply means and the original developer supply means, respectively, and supplies the hydrophilic treatment liquid and the developer in that order onto the substrate held by the rotation holding means;
A flow rate adjusting means for adjusting the flow rate of at least one of the hydrophilic treatment solution and the original developer;
In the hydrophilization process, at least the hydrophilization process liquid is sent to the nozzle, and in the development process, the hydrophilization process liquid and the original developer are mixed, and the flow rate adjusting means is discharged so that the developer of a predetermined concentration is discharged from the nozzle. And a control means to operate,
The control means supplies the developer to the substrate during the development process, and then drives the rotation holding means to temporarily rotate the substrate to temporarily shake off the developer on the substrate. After passing through the process of shaking off the developer at least once, a new developer supplied from the nozzle is deposited on the substrate, and then the developer on the substrate in the course of shaking off the developer. The substrate developing apparatus that operates the flow rate adjusting means so that the hydrophilic treatment liquid is always supplied to the substrate during the period in which the liquid is once shaken.

The substrate developing apparatus according to claim 1,
The control means further includes a substrate developing apparatus that controls the period during which the developer is supplied to the substrate during the process of shaking off the developer to be shorter than the period during which the developer is accumulated on the substrate.

The substrate developing apparatus according to claim 1 or 2,
The control unit further supplies a low concentration developer to the substrate at the beginning of the development process, and then gradually increases the concentration of the developer supplied to the substrate. A substrate developing device for operating the flow rate adjusting means to be supplied to the substrate.

The substrate developing apparatus according to any one of claims 1 to 3,
A substrate developing apparatus in which a check valve is provided at each connection portion on the nozzle side where the hydrophilic treatment liquid supply unit and the original developer supply unit communicate with each other .