JP3710735B2

JP3710735B2 - Substrate development processing method and development processing apparatus

Info

Publication number: JP3710735B2
Application number: JP2001263934A
Authority: JP
Inventors: 雅和真田; 修玉田; 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: 2001-08-31
Filing date: 2001-08-31
Publication date: 2005-10-26
Anticipated expiration: 2021-08-31
Also published as: JP2003077800A

Description

【０００１】
【発明の属する技術分野】
この発明は、半導体ウエハ、液晶表示装置用ガラス基板、フォトマスク用ガラス基板、光ディスク用基板等の基板の表面に形成され露光装置によって露光された後のレジスト膜に現像液を供給してレジスト膜を現像処理する基板の現像処理方法および現像処理装置に関する。
【０００２】
【従来の技術】
例えば半導体デバイスの製造プロセスにおける露光・現像工程において、基板上に形成されるレジストパターンの加工寸法は、露光波長の短波長化やレンズ開口数の増大などによって解像度が向上することに伴い、年々微細化している。一方、解像度の向上とは相反して、露光機の焦点深度（ＤＯＦ）が小さくなり、レジストパターンの仕上りに対する焦点合せの裕度（フォーカスマージン）が小さくなっている。すなわち、解像度Ｒは、Ｒ＝Ｋ_１・λ／ＮＡ（Ｋ_１：定数、λ：露光波長、ＮＡ：レンズの開口数）の式で表され、一方、焦点深度は、ＤＯＦ＝Ｋ_２・λ／（ＮＡ）^２（Ｋ_２：定数）の式で表されるが、解像度を向上させるために露光波長λを短くすればするほど、またレンズの開口数ＮＡを増大させればさせるほど、焦点深度は小さくなって、露光機における焦点合せのための調整が困難となっている。
【０００３】
【発明が解決しようとする課題】
上記したように、近年、焦点深度が小さくなり、フォーカスマージンが非常に小さくなっている（例えば１μｍ以下）ため、露光機において焦点ずれを起こすと、レジスト膜の厚みや下地基板の状態などによっては、所望寸法通りのレジストパターンが精度良く得られず、歩留りが低下する、といった問題点を生じるようになっている。
【０００４】
この発明は、以上のような事情に鑑みてなされたものであり、露光工程で多少の焦点ずれを生じても、現像処理後におけるレジストパターンの寸法変動（所望寸法からのずれ）を小さくすることができる基板の現像処理方法を提供すること、ならびに、その方法を好適に実施することができる基板の現像処理装置を提供することを目的とする。
【０００５】
【課題を解決するための手段】
請求項１に係る発明は、基板の表面に形成された露光後のレジスト膜に現像液を供給してレジスト膜を現像処理する基板の現像処理方法において、現像処理中における前記レジスト膜の表面へ光を照射してその反射光の強度を連続して測定し、その反射光強度の変化を示す波形曲線において振幅が０となった時点で現像反応を終了させることを特徴とする。
【０００６】
請求項２に係る発明は、基板の表面に形成された露光後のレジスト膜に現像液を供給してレジスト膜を現像処理する基板の現像処理方法において、レジスト膜を現像処理しつつそのレジスト膜の表面へ光を照射してその反射光の強度を連続して測定し、その反射光強度の変化を示す波形曲線を予め得ておき、その波形曲線において振幅が０となった時点で現像反応を終了させることを特徴とする。
【０００９】
請求項３に係る発明は、表面に露光後のレジスト膜が形成された基板を水平姿勢に保持する基板保持手段と、この基板保持手段に保持された基板上へ現像液を吐出する現像液吐出手段と、前記基板保持手段に保持された基板上へ純水を吐出する純水吐出手段と、を備えた基板の現像処理装置において、基板の表面に形成されたレジスト膜の表面へ光を照射してその反射光の強度を連続して測定する測定手段と、この測定手段による測定結果に基づいて、反射光強度の変化を示す波形曲線において振幅が０となった時点を判別し、その時点で前記純水吐出手段からの純水の吐出を開始させて現像反応を終了させるように制御する制御手段と、をさらに備えたことを特徴とする。
【００１０】
請求項４に係る発明は、請求項３記載の現像処理装置において、前記純水吐出手段が前記現像液吐出手段と同様の構成であり同様に動作することを特徴とする。
【００１１】
請求項５に係る発明は、請求項４記載の現像処理装置において、前記現像液吐出手段が、下端面にスリット状吐出口を有し基板に対して相対的に水平方向へ移動しつつスリット状吐出口から基板上へ現像液を吐出する現像液吐出ノズルを備えて構成され、前記純水吐出手段が、下端面にスリット状吐出口を有し基板に対して相対的に水平方向へかつ前記現像液吐出ノズルと同一方向へ同一速度で移動しつつスリット状吐出口から基板上へ純水を吐出する純水吐出ノズルを備えて構成されたことを特徴とする。
【００１２】
ここで、図２に模式的に部分拡大断面図を示すように、基板Ｗの表面に形成された露光後のレジスト膜１を現像液によって現像処理したとき、現像の前期段階、すなわち（ａ）に示した状態から（ｂ）に示した状態へ変化する段階では、レジストパターンの線幅の寸法変化率が大きく、後期段階、すなわち（ｂ）に示した状態から（ｃ）に示した状態へ変化する段階では、寸法変化率が小さくなる。これは、現像の前期段階ではレジスト膜１の可溶部分２における下方向（深さ方向）への急激な溶解反応が進行し、後期段階では可溶部分２における横方向への比較的遅い溶解反応が進行することによるものと考えられる。そして、現像の後期段階での可溶部分２の横方向への溶解反応は、露光部分（潜像）と非露光部分との境界線（可溶部分２と不溶部分３との境界線）４が終点となり、後期段階の現像時間が十分に与えられたときには、その境界線４がレジストパターンに反映されることになる。したがって、露光の際に焦点ずれを生じていた場合には、上記したように近年においてフォーカスマージンが非常に小さくなっているので、焦点ずれがレジストパターンの寸法のずれとなって忠実に現れることになる。このため、従来においては、焦点ずれが問題となっていたのである。
【００１５】
請求項１に係る発明の基板の現像処理方法では、現像処理中におけるレジスト膜の表面へ光を照射してその反射光の強度を連続して測定する。ここで、図２の（ａ）に示した状態から（ｂ）に示した状態へ変化する現像の前期段階では、レジスト膜１の可溶部分２の厚みが次第に薄くなり、一方、図２の（ｂ）に示した状態では、可溶部分２が底面５に到達するまで既に溶解しているので、（ｂ）に示した状態から（ｃ）に示した状態へ変化する後期段階では、前期段階のような膜厚の変化を生じない。このため、現像処理中におけるレジスト膜の表面へ光を照射すると、現像の前期段階では、膜厚の変化による光干渉を生じ、後期段階では、光干渉を生じなくなる。したがって、図３に示すように反射光強度の変化を示す波形曲線Ｂにおいて振幅が０となる現像時間Ｔ２は、膜厚の変化による光干渉を生じる前期段階が終了して、光干渉を生じなくなる後期段階へ移行する時点に相当するので、その現像時間Ｔ２が経過した時点を現像反応の終了時点とする。これにより、図２の（ｂ）に示すように、レジスト膜１の可溶部分２が溶解して底面５に到達した時点、すなわち上記説明に従って言えば現像の前期段階が終了して後期段階へ移行する時点以降で、可溶部分２の全体が溶解する時点、すなわち現像の後期段階が終了する時点より前に、現像反応が終了させられる。したがって、露光工程で多少の焦点ずれを生じていても、その焦点ずれがレジストパターンの寸法のずれとなって反映される前に現像処理が終わるので、レジストパターンの仕上りに対するフォーカスマージンが大きくなる。
【００１６】
請求項２に係る発明の基板の現像処理方法では、レジスト膜を現像処理しつつそのレジスト膜の表面へ光を照射してその反射光の強度を連続して測定し、図３に示すように反射光強度の変化を示す波形曲線Ｂを予め得ておき、その波形曲線Ｂにおいて振幅が０となる現像時間Ｔ２を求める。その現像時間Ｔ２は、上記したように、膜厚の変化による光干渉を生じる前期段階が終了して、光干渉を生じなくなる後期段階へ移行する時点に相当するので、その現像時間Ｔ２が経過した時点を現像反応の終了時点とする。これにより、請求項１に係る発明と同様に、レジスト膜１の可溶部分２が溶解して底面５に到達した時点、すなわち現像の前期段階が終了して後期段階へ移行する時点以降で、可溶部分２の全体が溶解する時点、すなわち現像の後期段階が終了する時点より前に、現像反応が終了させられる。したがって、露光工程で多少の焦点ずれを生じていても、その焦点ずれがレジストパターンの寸法のずれとなって反映される前に現像処理が終わるので、レジストパターンの仕上りに対するフォーカスマージンが大きくなる。
【００１７】
請求項３に係る発明の基板の現像処理装置においては、測定手段により、基板の表面に形成されたレジスト膜の表面へ光が照射されてその反射光の強度が連続して測定される。そして、制御手段により、測定手段による測定結果に基づいて、図３に示すように反射光強度の変化を示す波形曲線Ｂにおいて振幅が０となった時点が判別され、その時点で純水吐出手段が制御されて、純水吐出手段から基板上への純水の吐出が開始され、現像反応が終了させられる。このようにすることにより、請求項１に係る発明の現像処理方法が実施されて、請求項１に係る発明の上記作用が奏される。
【００１８】
請求項３に係る発明の現像処理装置を使用して請求項１に係る発明の上記作用が奏されると、現像の前期段階が終了した時点で現像反応が終了させられるので、現像時間が従来より短くなる。ところで、例えば、現像液吐出手段から基板の中心部へ吐出された現像液は、基板の回転に伴って基板全面へ広がっていき、あるいは、現像液吐出手段から静止した基板上へ現像液を供給する場合には、現像液は、基板の全面にわたって順次吐出されていく。そして、現像液を基板上へ吐出してから或る時間が経過した後に、純水吐出手段から基板上へ純水を吐出して現像反応を終了させるが、従来のように現像時間が十分に長ければ、現像液供給時から純水供給時までの、レジスト膜と現像液との接触時間（現像反応の時間）が、基板面内の位置によって相違しても、その相違による影響を無視することができる。ところが、上記したように現像時間が従来より短くなると、基板面内の各位置におけるレジスト膜と現像液との接触時間の相違が、それぞれの位置におけるレジスト膜の可溶部分の溶解状態の差となって現れる可能性がある。請求項４に係る発明の現像処理装置では、純水吐出手段と現像液吐出手段とが同様の構成であり同様に動作するので、現像液供給時から純水供給時までの、レジスト膜と現像液との接触時間を、基板の全面においてほぼ等しくすることが可能になる。このため、基板の全面においてレジスト膜の可溶部分の溶解状態を同じにすることが可能になる。
【００１９】
請求項５に係る発明の現像処理装置では、現像液吐出ノズルを基板に対して相対的に水平方向へ移動させつつ下端面のスリット状吐出口から基板上へ現像液を吐出して、いわゆるスリットスキャン現像が行われる。そして、現像液を基板上へ供給してから或る時間が経過した後に、純水吐出ノズルを基板に対して相対的に水平方向へかつ現像液吐出ノズルと同一方向へ同一速度で移動させつつ下端面のスリット状吐出口から基板上へ純水が吐出されて、レジスト膜の現像反応が終了させられる。したがって、レジスト膜と現像液との接触時間（現像反応の時間）が基板の全面において等しくなる。このため、現像時間が従来より短くなっても、レジスト膜の可溶部分の溶解状態が基板の全面において同じになる。
【００２０】
【発明の実施の形態】
以下、この発明の好適な実施形態について図１を参照しながら説明する。
【００２１】
図１は、この発明に係る基板の現像処理方法を実施するために使用される現像処理装置の構成の１例を示す概略斜視図である。この現像処理装置は、基板Ｗを水平姿勢で吸着保持するスピンチャック１０、上端部に基板保持部１０が固着され鉛直に支持された回転支軸１２、および、回転支軸１２に回転軸が連結され基板保持部１０および回転支軸１２を鉛直軸回りに回転させるスピンモータ１４を備えている。図示していないが、基板保持部１０の周囲には、基板保持部１０上の基板Ｗを取り囲むように回収カップが配設されている。
【００２２】
また、スピンチャック１０に保持された基板Ｗより上方の位置に、現像液吐出ノズル１６および純水吐出ノズル１８が配設されている。現像液吐出ノズル１６および純水吐出ノズル１８は、詳細な構造を図示していないが、それぞれ、下端面に長手方向に延びるスリット状吐出口を有し、そのスリット状吐出口に連通する液溜り室が内部に形設されている。現像液吐出ノズル１６には、その液溜り室に連通する現像液供給口２０が形成されており、その現像液供給口２０に、現像液供給源に接続された現像液供給管２２が連通接続され、現像液供給管２２に開閉制御弁２４が介挿されている。また、純水吐出ノズル１８には、その液溜り室に連通する純水供給口２６が形成されており、その純水供給口２６に、純水供給源に接続された純水供給管２８が連通接続され、純水供給管２８に開閉制御弁３０が介挿されている。
【００２３】
現像液吐出ノズル１６と純水吐出ノズル１８とは、それぞれ、スピンチャック１０に保持された基板Ｗに対して相対的に水平方向へかつ互いに同一方向へ同一速度で移動するように支持されている。例えば、現像液吐出ノズル１６と純水吐出ノズル１８とが１つの共用ノズルアームにそれぞれ水平姿勢で吊着され、その共用ノズルアームがアーム駆動部に保持され、アーム駆動部が、現像液吐出ノズル１６および純水吐出ノズル１８の長手方向と直交する方向に配設されたガイドレールと摺動自在に係合した構成を有する移動機構が設けられている。そして、現像液吐出ノズル１６は、矢印Ａで示す方向へ移動しつつ下端面のスリット状吐出口から基板Ｗ上へ現像液を吐出して、スリットスキャン現像が行われる。また、純水吐出ノズル１８は、同じく矢印Ａで示す方向へ移動しつつ下端面のスリット状吐出口から基板Ｗ上へ純水を吐出する。
【００２４】
なお、現像液吐出ノズル１６と純水吐出ノズル１８とをそれぞれ設ける代わりに、１つの共用吐出ノズルを設け、その共用吐出ノズルに現像液供給口と純水供給口とをそれぞれ形成し、現像液供給口に、現像液供給源に接続され開閉制御弁が介挿された現像液供給管を連通接続するとともに、純水供給口に、純水供給源に接続され開閉制御弁が介挿された純水供給管を連通接続して、共用吐出ノズルのスリット状吐出口から基板上へ現像液および純水を選択的にそれぞれ吐出させるような構成とすることもできる。
【００２５】
スピンチャック１０に保持された基板Ｗの上方には、基板Ｗの表面と対向するように反射光強度測定ヘッド３２が配設されている。この反射光強度測定ヘッド３２は、現像処理中、基板Ｗの表面に形成されたレジスト膜の表面へ光を照射してその反射光の強度を連続して測定するためのものである。反射光強度測定ヘッド３２は、それを制御するコントローラ３４に接続され、コントローラ３４は、マイクロコンピュータ（マイコン）３６に接続されている。また、マイコン３６は、スピンモータ１４および開閉制御弁２４、３０に接続され、また、図示していないが、現像液吐出ノズル１６および純水吐出ノズル１８を水平方向へ走査するアーム駆動部に接続されている。
【００２６】
反射光強度測定ヘッド３２により連続して測定された反射光強度を示す測定信号は、マイコン３６へ送られ、マイコン３６において、現像反応を終了させる時点を決定するための演算処理が行われる。すなわち、現像処理中におけるレジスト膜が、図２の（ａ）に示した状態から（ｂ）に示した状態へ変化する現像の前期段階では、レジスト膜１の可溶部分２の厚みが次第に薄くなり、一方、図２の（ｂ）に示した状態から（ｃ）に示した状態へ変化する後期段階では、前期段階のような膜厚の変化を生じない。このため、現像処理中におけるレジスト膜１の表面へ光を照射すると、現像の前期段階では膜厚の変化による光干渉を生じ、後期段階では光干渉を生じなくなり、図３に示すように反射光強度の変化を示す波形曲線Ｂが得られる。このような波形曲線Ｂにおいて振幅が０となる現像時間Ｔ２は、膜厚の変化による光干渉を生じる前期段階が終了して、光干渉を生じなくなる後期段階へ移行する時点に相当する。この発明に係る現像処理方法では、前期段階が終了して後期段階へ移行する時点で現像反応を終了させるようにする。したがって、マイコン３６において、図３に示したような波形曲線Ｂにおいて振幅が０となった時点が判別される。
【００２７】
次に、上記したような構成を備えた現像処理装置による処理動作の１例について説明する。
【００２８】
表面に露光後のレジスト膜が形成された基板Ｗが装置内に搬入されて、スピンチャック１０に基板Ｗが保持されると、現像液供給管２２に介挿された開閉制御弁２４を開き、現像液供給源から現像液供給管２２を通して現像液吐出ノズル１６へ現像液を供給する。そして、現像液吐出ノズル１６の下端面のスリット状吐出口から現像液を基板Ｗ上へ吐出させつつ、現像液吐出ノズル１６を矢印Ａで示す方向に走査する。これにより、基板Ｗ上に現像液が供給されて液盛りされる。基板Ｗの全面に液盛りされると、現像液供給管２２に介挿された開閉制御弁２４を閉じ、現像液吐出ノズル１６を矢印Ａで示す方向と逆方向へ移動させて元の位置まで戻す。そして、基板Ｗを静止させたままにして、基板Ｗの表面上のレジスト膜を現像処理する。この現像処理の間、反射光強度測定ヘッド３２により、基板Ｗの表面に形成されたレジスト膜の表面へ光を照射してその反射光の強度を連続して測定する。
【００２９】
マイコン３６により、上記したように反射光強度測定ヘッド３２による測定結果に基づいて現像反応を終了させる時点が判別されると、マイコン３６から制御信号を出力して、純水供給管２８に介挿された開閉制御弁３０を開き、純水供給源から純水供給管２８を通して純水吐出ノズル１８へ純水（リンス液）を供給する。そして、純水吐出ノズル１８の下端面のスリット状吐出口から純水を基板Ｗ上へ吐出させつつ、純水吐出ノズル１８を矢印Ａで示す方向へ現像液吐出ノズル１６と同一の速度で移動させる。これにより、基板Ｗの表面上のレジスト膜の現像反応が終了させられる。基板Ｗの全面に純水が供給されると、純水供給管２８に介挿された開閉制御弁３０を閉じ、純水吐出ノズル１８を矢印Ａで示す方向と逆方向へ移動させて元の位置まで戻す。
【００３０】
純水吐出ノズル１８を元の位置まで移動させると同時に、スピンモータ１４を作動させて、スピンチャック１０に保持された基板Ｗを水平面内で鉛直軸回りに回転させることにより、基板Ｗを乾燥させる。基板Ｗの乾燥処理が終了すると、スピンモータ１４を停止させ、基板Ｗを装置内から搬出する。
【００３１】
以上のように、現像の前期段階が終了して後期段階へ移行する時点で現像反応を終了させる、といった方法で現像処理を行うことにより、露光工程で多少の焦点ずれを生じていても、その焦点ずれがレジストパターンの寸法のずれとなって反映される前に現像処理が終わる。このため、レジストパターンの仕上りに対するフォーカスマージンが大きくなって、歩留りが向上することになる。また、この方法では、現像の前期段階が終了して後期段階へ移行する時点で現像反応を終了させるが、通常、この時点は現像反応開始時から５秒〜１５秒が経過した時点であり、従来の現像処理方法における現像反応時間が６０秒〜９０秒であったのに比べて、スループットが大幅に向上することになる。
【００３２】
また、現像液を基板Ｗ上へ供給してから或る時間が経過した後に、純水吐出ノズル１８を現像液吐出ノズル１６と同一方向へ同一速度で移動させつつ基板Ｗ上へ純水が吐出されて、レジスト膜の現像反応が終了させられるので、レジスト膜と現像液との接触時間（現像反応の時間）が基板Ｗの全面において等しくなる。もう少し具体的に説明すると、例えば、基板Ｗの直径が３００ｍｍで、現像液吐出ノズル１６の相対移動速度が５０ｍｍ／秒であるとした場合、１つの基板Ｗ面内においてレジスト膜と現像液との接触開始時点が最大で６秒の時間差を生じることになる。従来のように、現像反応時間が６０秒〜９０秒であったときには、前記時間差によるレジスト膜の溶解状態への影響を無視することができる。これに対し、上記したように現像時間が従来より短くなると、基板Ｗ面内の各位置におけるレジスト膜と現像液との接触時間の相違が、それぞれの位置におけるレジスト膜の可溶部分の溶解状態の差となって現れる可能性がある。ところが、純水吐出ノズル１８を現像液吐出ノズル１６と同一方向へ同一速度で移動させつつ基板Ｗ上へ純水を供給するようにすると、レジスト膜と現像液との接触時間が基板Ｗの全面において等しくなる。したがって、現像時間が従来より短くなっても、レジスト膜の可溶部分の溶解状態が基板Ｗの全面において同じになる。
【００３３】
なお、上記した実施形態では、現像処理を行いながら、反射光強度測定ヘッド３２により、スピンチャック１０に保持された基板Ｗの表面上のレジスト膜の表面へ光を照射してその反射光の強度を連続して測定し、その測定結果に基づいて現像反応を終了させる時点をマイコン３６で判別し、マイコン３６から制御信号を出力して、レジスト膜の現像反応を終了させるようにしたが、予め、反射光強度の変化を示す波形曲線Ｂを得て、その波形曲線Ｂにおいて振幅が０となる現像時間Ｔ２を求めておき、現像開始時からその現像時間Ｔ２が経過した時点で現像反応を終了させるようにすることもできる。
【００３４】
また、上記した実施形態では、スリットスキャン現像を行う例について説明したが、現像処理方式は、スリットスキャン方式に限らない。但し、現像液吐出手段と純水吐出手段とは、同様の構成で同様に動作するものをそれぞれ使用することが好ましい。例えば、現像液吐出ノズルから基板の中心部へ現像液を吐出し、基板の回転に伴って現像液が基板全面へ広がるようにして、現像処理を行う方式では、純水吐出ノズルも、現像液吐出ノズルと同様に、基板の中心部へ純水を吐出し基板の回転に伴って純水が基板全面へ広がるような形式のものを使用する。
【００３６】
なお、上記した説明では、現像の前期段階が終了して後期段階へ移行する時点で現像反応を終了させるようにしているが、必ずしも現像の前期段階が終了した直後に現像反応を終了させる必要は無く、現像の前期段階が終了した時点以降で後期段階が終了する時点より前の適当な時点で現像反応を終了させるようにしても構わない。
【００３７】
【発明の効果】
請求項１に係る発明の基板の現像処理方法によると、基板の表面に形成されたレジスト膜の可溶部分の厚みが次第に薄くなる現像の前期段階が終了して膜厚の変化を生じない後期段階へ移行する時点を現像反応の終了時点とし、現像処理中にその時点を検出して現像反応を終了させることにより、露光工程で多少の焦点ずれを生じても、レジストパターンの仕上りに対するフォーカスマージンが大きくなるので、所望寸法通りのレジストパターンを精度良く得ることができ、歩留りを向上させることができる。また、現像の前期段階が終了して後期段階へ移行する時点以降で可溶部分全体が溶解する時点より前に現像反応を終了させるので、従来に比べてスループットを向上させることができる。
【００４０】
請求項２に係る発明の基板の現像処理方法によると、基板の表面に形成されたレジスト膜の可溶部分の厚みが次第に薄くなる現像の前期段階が終了して膜厚の変化を生じない後期段階へ移行する時点を現像反応の終了時点とすることにより、露光工程で多少の焦点ずれを生じても、レジストパターンの仕上りに対するフォーカスマージンが大きくなるので、所望寸法通りのレジストパターンを精度良く得ることができ、歩留りを向上させることができる。また、現像の前期段階が終了して後期段階へ移行する時点以降で可溶部分全体が溶解する時点より前に現像反応を終了させるので、従来に比べてスループットを向上させることができる。
【００４１】
請求項３に係る発明の基板の現像処理装置を使用すると、請求項１に係る発明の現像処理方法を好適に実施することができるので、請求項１に係る発明の上記効果を確実に得ることができる。
【００４２】
請求項４に係る発明の現像処理装置では、レジスト膜と現像液との接触時間を基板の全面においてほぼ等しくすることができるので、現像時間が従来より短くなっても、レジスト膜の可溶部分の溶解状態を基板の全面において同じにすることができる。
【００４３】
請求項５に係る発明の現像処理装置では、スリットスキャン現像が行われ、レジスト膜と現像液との接触時間を基板の全面において等しくすることができるので、現像時間が従来より短くなっても、レジスト膜の可溶部分の溶解状態を基板の全面において同じにすることができる。
【図面の簡単な説明】
【図１】この発明に係る基板の現像処理方法を実施するために使用される現像処理装置の構成の１例を示す概略斜視図である。
【図２】基板の表面に形成された露光後のレジスト膜を現像液によって現像処理したときの、レジスト膜の可溶部分における溶解反応の進行状態を模式的に示す部分拡大断面図である。
【図３】現像処理中におけるレジスト膜の表面へ光を照射したときの反射光強度の変化を示す図である。
【符号の説明】
Ｗ基板
１レジスト膜
２可溶部分
３不溶部分
４露光部分と非露光部分との境界線（可溶部分と不溶部分との境界線）
５可溶部分の底面
１０スピンチャック
１２回転支軸
１４スピンモータ
１６現像液吐出ノズル
１８純水吐出ノズル
２０現像液吐出ノズルの現像液供給口
２２現像液供給管
２４、３０開閉制御弁
２６純水吐出ノズルの純水供給口
２８純水供給管
３２反射光強度測定ヘッド
３４コントローラ
３６マイコン[0001]
BACKGROUND OF THE INVENTION
The present invention provides a resist film by supplying a developer to a resist film formed on the surface of a substrate such as a semiconductor wafer, a glass substrate for a liquid crystal display device, a glass substrate for a photomask, or an optical disk substrate and exposed by an exposure device. The present invention relates to a development processing method and a development processing apparatus for a substrate on which development processing is performed.
[0002]
[Prior art]
For example, in the exposure / development process in the semiconductor device manufacturing process, the processing dimensions of the resist pattern formed on the substrate are becoming finer year by year as the resolution is improved by shortening the exposure wavelength and increasing the lens numerical aperture. It has become. On the other hand, contrary to the improvement in resolution, the depth of focus (DOF) of the exposure machine is reduced, and the focus margin (focus margin) for the finish of the resist pattern is reduced. That is, the resolution R is R = K₁・ Λ / NA (K₁: Constant, λ: exposure wavelength, NA: lens numerical aperture), while the depth of focus is DOF = K₂・ Λ / (NA)²(K₂: Constant), the depth of focus decreases as the exposure wavelength λ is shortened and the numerical aperture NA of the lens is increased in order to improve the resolution. Adjustment for focusing is difficult.
[0003]
[Problems to be solved by the invention]
As described above, in recent years, the depth of focus has become smaller and the focus margin has become very small (for example, 1 μm or less). However, there is a problem that a resist pattern having a desired dimension cannot be obtained with high accuracy and the yield is lowered.
[0004]
The present invention has been made in view of the circumstances as described above. Even if a slight defocus occurs in the exposure process, the dimensional variation (deviation from the desired dimension) of the resist pattern after development processing is reduced. An object of the present invention is to provide a substrate development processing method that can perform the above-described process, and to provide a substrate development processing apparatus that can suitably implement the method.
[0005]
[Means for Solving the Problems]
  The invention according to claim 1 is a substrate development method for developing a resist film by supplying a developer to an exposed resist film formed on the surface of the substrate.During the development process, the surface of the resist film is irradiated with light, the intensity of the reflected light is continuously measured, and when the amplitude of the waveform curve showing the change in the reflected light intensity becomes zero.The development reaction is terminated.
[0006]
  The invention according to claim 2A substrate for developing a resist film by supplying a developing solution to the exposed resist film formed on the surface of the substrate.In the development processing method,While developing the resist film, the surface of the resist film is irradiated with light, and the intensity of the reflected light is continuously measured, and a waveform curve indicating the change in the reflected light intensity is obtained in advance. When the amplitude reaches 0, the development reaction is terminated.It is characterized by that.
[0009]
  Claim 3The invention according to the present invention includes a substrate holding unit that holds a substrate on which a resist film after exposure is formed on a surface in a horizontal posture, a developer discharging unit that discharges a developer onto the substrate held by the substrate holding unit, And a pure water discharge means for discharging pure water onto the substrate held by the substrate holding means, and irradiating the resist film formed on the surface of the substrate with light, Based on the measurement means for continuously measuring the intensity of the reflected light and the measurement result by the measurement means, the time point when the amplitude becomes zero in the waveform curve indicating the change in the reflected light intensity is determined. And a control means for controlling to start the development reaction by starting the discharge of pure water from the water discharge means.
[0010]
  Claim 4The invention according toClaim 3In the development processing apparatus described above, the pure water discharge unit has the same configuration as the developer discharge unit and operates in the same manner.
[0011]
  Claim 5The invention according toClaim 4In the development processing apparatus described above, the developer discharge means has a slit-shaped discharge port on a lower end surface and discharges the developer from the slit-shaped discharge port onto the substrate while moving in a horizontal direction relative to the substrate. A developer discharge nozzle is provided, and the pure water discharge means has a slit-like discharge port at its lower end surface, is relatively horizontal with respect to the substrate and at the same speed in the same direction as the developer discharge nozzle. A pure water discharge nozzle that discharges pure water from the slit-shaped discharge port onto the substrate while moving is provided.
[0012]
Here, as shown schematically in FIG. 2 in a partially enlarged sectional view, when the exposed resist film 1 formed on the surface of the substrate W is developed with a developer, the first stage of development, that is, (a) At the stage of changing from the state shown in (b) to the state shown in (b), the dimensional change rate of the line width of the resist pattern is large. From the latter stage, that is, from the state shown in (b) to the state shown in (c). In the changing stage, the dimensional change rate becomes small. This is because a rapid dissolution reaction in the downward direction (depth direction) in the soluble portion 2 of the resist film 1 proceeds in the early stage of development, and a relatively slow dissolution in the lateral direction in the soluble portion 2 in the later stage. This is thought to be due to the progress of the reaction. Then, the dissolution reaction in the lateral direction of the soluble part 2 at the later stage of development is a boundary line between the exposed part (latent image) and the non-exposed part (boundary line between the soluble part 2 and the insoluble part 3) 4. Is the end point, and when the development time in the later stage is sufficiently given, the boundary line 4 is reflected in the resist pattern. Therefore, if defocusing occurs during exposure, the focus margin has become very small in recent years as described above, so that defocusing appears faithfully as a shift in the resist pattern dimensions. Become. For this reason, in the past, defocus has been a problem.
[0015]
  Claim 1Of the inventionSubstrateIn the development processing method, light is irradiated onto the surface of the resist film during the development processing, and the intensity of the reflected light is continuously measured. Here, in the first stage of development in which the state shown in FIG. 2A changes to the state shown in FIG. 2B, the thickness of the soluble portion 2 of the resist film 1 gradually decreases. In the state shown in (b), since the soluble part 2 has already dissolved until it reaches the bottom surface 5, in the latter stage of changing from the state shown in (b) to the state shown in (c), No change in film thickness as in the stage. For this reason, when light is applied to the surface of the resist film during the development process, light interference occurs due to a change in film thickness in the first stage of development, and light interference does not occur in the second stage. Therefore,FIG.As shown in FIG. 4, the development time T2 in which the amplitude is zero in the waveform curve B indicating the change in the reflected light intensity is completed, and the first stage in which the optical interference due to the change in the film thickness is completed is shifted to the later stage in which the optical interference does not occur Since the development time T2 has elapsed, the development reaction end time is determined.. Thus, as shown in FIG. 2B, when the soluble portion 2 of the resist film 1 is dissolved and reaches the bottom surface 5, that is, according to the above description, the first stage of development is completed and the second stage is reached. After the transition, the development reaction is terminated before the entire soluble portion 2 is dissolved, that is, before the end of the later stage of development. Therefore, even if a slight defocus occurs in the exposure process, the development process is completed before the defocus is reflected as a misalignment of the resist pattern, so that the focus margin for the finish of the resist pattern is increased.
[0016]
  Claim 2Of the inventionSubstrateIn the development processing method, while the resist film is developed, the surface of the resist film is irradiated with light, and the intensity of the reflected light is continuously measured.FIG.A waveform curve B indicating the change in reflected light intensity is obtained in advance, and a development time T2 in which the amplitude is 0 in the waveform curve B is obtained. As described above, the development time T2 corresponds to the time point when the first stage in which the optical interference due to the change in the film thickness occurs is completed and the process shifts to the latter stage in which the optical interference does not occur. Time is the end of the development reaction. Thus, as in the invention according to claim 1, after the soluble portion 2 of the resist film 1 is dissolved and reaches the bottom surface 5, that is, after the time when the first stage of development is completed and the process proceeds to the second stage, The development reaction is terminated before the entire soluble portion 2 is dissolved, that is, before the end of the later stage of development. Therefore, even if a slight defocus occurs in the exposure process, the development process is completed before the defocus is reflected as a misalignment of the resist pattern, so that the focus margin for the finish of the resist pattern is increased.
[0017]
  Claim 3In the substrate development processing apparatus according to the invention, the measurement means irradiates the surface of the resist film formed on the surface of the substrate with light, and continuously measures the intensity of the reflected light. And based on the measurement result by the measurement means by the control means,FIG.As shown in FIG. 4, the time point when the amplitude becomes 0 is determined in the waveform curve B indicating the change in the reflected light intensity, and the pure water discharge means is controlled at that time, and the pure water from the pure water discharge means onto the substrate is determined. Discharge is started and the development reaction is terminated. By doing this,Claim 1The development processing method of the invention according to the present invention is carried out, and the above-described action of the invention of claim 1 is exhibited.
[0018]
  Claim 3When the above-described operation of the invention according to claim 1 is performed using the development processing apparatus according to the invention, the development reaction is terminated when the first stage of development is completed, so the development time is shorter than before. . By the way, for example, the developer discharged from the developer discharge means to the central portion of the substrate spreads over the entire surface of the substrate as the substrate rotates, or the developer is supplied onto the stationary substrate from the developer discharge means. In this case, the developer is sequentially discharged over the entire surface of the substrate. Then, after a certain time has elapsed since the developer was discharged onto the substrate, pure water was discharged from the pure water discharge means onto the substrate to terminate the development reaction. If it is long, even if the contact time (development reaction time) between the resist film and the developer from the time of supplying the developer to the time of supplying pure water differs depending on the position in the substrate surface, the influence of the difference is ignored. be able to. However, as described above, when the development time is shorter than the conventional one, the difference in the contact time between the resist film and the developer at each position in the substrate surface is the difference in the dissolution state of the soluble portion of the resist film at each position. May appear.Claim 4In the development processing apparatus according to the invention, the pure water discharge means and the developer discharge means have the same configuration and operate in the same manner. The contact time can be made almost equal over the entire surface of the substrate. For this reason, it is possible to make the dissolution state of the soluble portion of the resist film the same over the entire surface of the substrate.
[0019]
  Claim 5In the development processing apparatus according to the invention, so-called slit scan development is performed by discharging the developer from the slit-like discharge port on the lower end surface while moving the developer discharge nozzle in the horizontal direction relative to the substrate. Done. Then, after a certain period of time has passed since the developer was supplied onto the substrate, the pure water discharge nozzle was moved in the horizontal direction relative to the substrate and in the same direction as the developer discharge nozzle at the same speed. Pure water is discharged onto the substrate from the slit-shaped discharge port on the lower end surface, and the development reaction of the resist film is terminated. Therefore, the contact time between the resist film and the developer (development reaction time) is equal over the entire surface of the substrate. For this reason, even if development time becomes shorter than before, the dissolution state of the soluble part of the resist film becomes the same over the entire surface of the substrate.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
A preferred embodiment of the present invention will be described below with reference to FIG.
[0021]
FIG. 1 is a schematic perspective view showing an example of the configuration of a development processing apparatus used for carrying out the substrate development processing method according to the present invention. In this development processing apparatus, the spin chuck 10 that holds the substrate W in a horizontal posture is held, the rotation support shaft 12 that is vertically supported with the substrate holding portion 10 fixed to the upper end, and the rotation shaft connected to the rotation support shaft 12. A spin motor 14 is provided for rotating the substrate holding unit 10 and the rotation support shaft 12 about the vertical axis. Although not shown, a recovery cup is disposed around the substrate holding unit 10 so as to surround the substrate W on the substrate holding unit 10.
[0022]
Further, a developer discharge nozzle 16 and a pure water discharge nozzle 18 are disposed at a position above the substrate W held by the spin chuck 10. The developer discharge nozzle 16 and the pure water discharge nozzle 18 are not shown in detail, but each has a slit-like discharge port extending in the longitudinal direction at the lower end surface, and a liquid reservoir communicating with the slit-like discharge port. A chamber is formed inside. The developer discharge nozzle 16 is formed with a developer supply port 20 that communicates with the liquid storage chamber, and a developer supply pipe 22 connected to the developer supply source is connected to the developer supply port 20. An open / close control valve 24 is inserted in the developer supply pipe 22. The pure water discharge nozzle 18 is formed with a pure water supply port 26 communicating with the liquid reservoir chamber. A pure water supply pipe 28 connected to a pure water supply source is connected to the pure water supply port 26. The open / close control valve 30 is inserted in the pure water supply pipe 28 in communication.
[0023]
The developer discharge nozzle 16 and the pure water discharge nozzle 18 are supported so as to move relative to the substrate W held by the spin chuck 10 in the horizontal direction and in the same direction at the same speed. . For example, the developer discharge nozzle 16 and the pure water discharge nozzle 18 are respectively suspended in a single horizontal nozzle arm in a horizontal posture, the shared nozzle arm is held by an arm drive unit, and the arm drive unit is a developer discharge nozzle. 16 and a pure water discharge nozzle 18 are provided with a moving mechanism having a configuration in which the guide rail is slidably engaged with a guide rail disposed in a direction perpendicular to the longitudinal direction. Then, the developer discharge nozzle 16 discharges the developer onto the substrate W from the slit-shaped discharge port on the lower end surface while moving in the direction indicated by the arrow A, and slit scan development is performed. The pure water discharge nozzle 18 also discharges pure water onto the substrate W from the slit-like discharge port on the lower end surface while moving in the direction indicated by the arrow A.
[0024]
Instead of providing each of the developer discharge nozzle 16 and the pure water discharge nozzle 18, one common discharge nozzle is provided, and a developer supply port and a pure water supply port are formed in the common discharge nozzle, respectively. A developer supply pipe connected to the developer supply source and having an open / close control valve interposed therein is connected to the supply port, and an open / close control valve is inserted into the pure water supply port and connected to the pure water supply source. A pure water supply pipe may be connected in communication so that the developer and pure water can be selectively discharged from the slit-like discharge port of the common discharge nozzle onto the substrate.
[0025]
A reflected light intensity measuring head 32 is disposed above the substrate W held by the spin chuck 10 so as to face the surface of the substrate W. This reflected light intensity measuring head 32 is for irradiating light onto the surface of the resist film formed on the surface of the substrate W during the development process and continuously measuring the intensity of the reflected light. The reflected light intensity measuring head 32 is connected to a controller 34 for controlling the reflected light intensity measuring head 32, and the controller 34 is connected to a microcomputer 36. Further, the microcomputer 36 is connected to the spin motor 14 and the open / close control valves 24 and 30, and is connected to an arm driving unit that scans the developer discharge nozzle 16 and the pure water discharge nozzle 18 in the horizontal direction, although not shown. Has been.
[0026]
  A measurement signal indicating the reflected light intensity continuously measured by the reflected light intensity measuring head 32 is sent to the microcomputer 36, and the microcomputer 36 performs an arithmetic process for determining a time point at which the development reaction is terminated. That is, in the first stage of development in which the resist film during the development process changes from the state shown in FIG. 2A to the state shown in FIG. 2B, the thickness of the soluble portion 2 of the resist film 1 is gradually reduced. On the other hand, in the latter stage where the state shown in FIG. 2B changes to the state shown in FIG. 2C, the film thickness does not change as in the previous stage. For this reason, when light is applied to the surface of the resist film 1 during the development process, light interference occurs due to a change in film thickness in the first stage of development, and light interference does not occur in the second stage.FIG.As shown in FIG. 4, a waveform curve B indicating a change in reflected light intensity is obtained. The development time T2 in which the amplitude is 0 in the waveform curve B corresponds to a point in time when the first stage in which the optical interference due to the change in the film thickness occurs and the second stage in which the optical interference does not occur is shifted to. In the development processing method according to the present invention, the development reaction is terminated when the first stage is completed and the process proceeds to the latter stage. Therefore, in the microcomputer 36,FIG.When the waveform curve B as shown in FIG.
[0027]
Next, an example of processing operation by the development processing apparatus having the above-described configuration will be described.
[0028]
When the substrate W on which the resist film after exposure is formed is carried into the apparatus and the substrate W is held by the spin chuck 10, the opening / closing control valve 24 inserted in the developer supply pipe 22 is opened, The developer is supplied from the developer supply source to the developer discharge nozzle 16 through the developer supply pipe 22. Then, the developer discharge nozzle 16 is scanned in the direction indicated by the arrow A while discharging the developer onto the substrate W from the slit-like discharge port on the lower end surface of the developer discharge nozzle 16. As a result, the developer is supplied onto the substrate W and accumulated. When liquid is deposited on the entire surface of the substrate W, the open / close control valve 24 inserted in the developer supply pipe 22 is closed, and the developer discharge nozzle 16 is moved in the direction opposite to the direction indicated by the arrow A to the original position. return. Then, the resist film on the surface of the substrate W is developed while leaving the substrate W stationary. During this development process, the reflected light intensity measuring head 32 irradiates light onto the surface of the resist film formed on the surface of the substrate W, and continuously measures the intensity of the reflected light.
[0029]
When the microcomputer 36 determines the time point at which the development reaction is terminated based on the measurement result by the reflected light intensity measuring head 32 as described above, the microcomputer 36 outputs a control signal and is inserted into the pure water supply pipe 28. The open / close control valve 30 is opened, and pure water (rinse liquid) is supplied from the pure water supply source to the pure water discharge nozzle 18 through the pure water supply pipe 28. The pure water discharge nozzle 18 is moved in the direction indicated by the arrow A at the same speed as the developer discharge nozzle 16 while discharging pure water onto the substrate W from the slit-like discharge port on the lower end surface of the pure water discharge nozzle 18. Let Thereby, the development reaction of the resist film on the surface of the substrate W is terminated. When pure water is supplied to the entire surface of the substrate W, the open / close control valve 30 inserted in the pure water supply pipe 28 is closed, and the pure water discharge nozzle 18 is moved in the direction opposite to the direction indicated by the arrow A to restore the original water. Return to position.
[0030]
The pure water discharge nozzle 18 is moved to the original position, and at the same time, the spin motor 14 is operated to rotate the substrate W held by the spin chuck 10 around the vertical axis in the horizontal plane, thereby drying the substrate W. . When the drying process of the substrate W is completed, the spin motor 14 is stopped and the substrate W is carried out of the apparatus.
[0031]
As described above, even if a slight defocus occurs in the exposure process, the development reaction is terminated when the first stage of development is completed and the development reaction is terminated at the time of transition to the latter stage. The development process is completed before the defocus is reflected as a dimensional shift of the resist pattern. For this reason, the focus margin for the finish of the resist pattern is increased, and the yield is improved. In this method, the development reaction is terminated at the time when the first stage of development is completed and the process proceeds to the latter stage. Usually, this time is the time when 5 to 15 seconds have elapsed from the start of the development reaction, Compared with the development reaction time of 60 seconds to 90 seconds in the conventional development processing method, the throughput is greatly improved.
[0032]
Further, after a certain period of time has passed since the developer was supplied onto the substrate W, pure water was discharged onto the substrate W while moving the pure water discharge nozzle 18 in the same direction as the developer discharge nozzle 16 at the same speed. As a result, the development reaction of the resist film is terminated, so that the contact time between the resist film and the developer (development reaction time) becomes equal over the entire surface of the substrate W. More specifically, for example, when the diameter of the substrate W is 300 mm and the relative moving speed of the developer discharge nozzle 16 is 50 mm / second, the resist film and the developer are separated within one substrate W surface. The contact start time will cause a time difference of 6 seconds at the maximum. As in the prior art, when the development reaction time is 60 seconds to 90 seconds, the influence of the time difference on the dissolved state of the resist film can be ignored. On the other hand, as described above, when the development time is shorter than the conventional one, the difference in the contact time between the resist film and the developer at each position in the surface of the substrate W is the dissolved state of the soluble portion of the resist film at each position. May appear as a difference. However, when pure water is supplied onto the substrate W while moving the pure water discharge nozzle 18 in the same direction as the developer discharge nozzle 16 at the same speed, the contact time between the resist film and the developer is the entire surface of the substrate W. Are equal. Therefore, even if the development time is shorter than before, the dissolved state of the soluble portion of the resist film is the same over the entire surface of the substrate W.
[0033]
In the embodiment described above, the intensity of the reflected light is obtained by irradiating the surface of the resist film on the surface of the substrate W held by the spin chuck 10 by the reflected light intensity measuring head 32 while performing the development process. The microcomputer 36 discriminates when the development reaction is terminated based on the measurement result and outputs a control signal from the microcomputer 36 to terminate the development reaction of the resist film. The waveform curve B showing the change in reflected light intensity is obtained, and the development time T2 in which the amplitude is 0 in the waveform curve B is obtained, and the development reaction ends when the development time T2 elapses from the start of development. It can also be made to do.
[0034]
In the above-described embodiment, an example in which slit scan development is performed has been described. However, the development processing method is not limited to the slit scan method. However, it is preferable to use the developer discharge means and the pure water discharge means that have the same configuration and operate similarly. For example, in a method in which a developing solution is discharged from a developing solution discharge nozzle to the center of the substrate and the developing solution spreads over the entire surface of the substrate as the substrate rotates, the pure water discharge nozzle also has a developing solution. Similar to the discharge nozzle, a type in which pure water is discharged to the center of the substrate and the pure water spreads over the entire surface of the substrate as the substrate rotates is used.
[0036]
In the above description, the development reaction is terminated at the time when the first stage of development ends and shifts to the second stage, but it is not always necessary to terminate the development reaction immediately after the first stage of development is completed. Alternatively, the development reaction may be terminated at an appropriate time after the end of the early stage of development and before the end of the later stage.
[0037]
【The invention's effect】
  According to the substrate development method of the invention of claim 1,The development process ends when the development stage where the soluble part of the resist film formed on the surface of the substrate is gradually thinned and the first stage of development is completed and the film transitions to the later stage where no change in film thickness occurs is determined. By detecting the point in time and terminating the development reaction,Even if a slight defocus occurs in the exposure process, the focus margin for the finish of the resist pattern is increased, so that a resist pattern having a desired dimension can be obtained with high accuracy and the yield can be improved. Further, since the development reaction is terminated before the time when the first stage of development is completed and the entire soluble portion is dissolved after the transition to the latter stage, the throughput can be improved as compared with the conventional case.
[0040]
  Claim 2Of the inventionSubstrateDevelopment processing methodaccording toThe development reaction ends when the first stage of development where the thickness of the soluble portion of the resist film formed on the surface of the substrate gradually decreases and the transition to the later stage where no change in film thickness occurs is made. ByEven if a slight defocus occurs in the exposure process, the focus margin for the finish of the resist pattern is increased, so that a resist pattern having a desired dimension can be obtained with high accuracy and the yield can be improved. In addition, since the development reaction is terminated before the time when the first stage of development is completed and the entire soluble portion is dissolved after the transition to the latter stage, the throughput can be improved as compared with the conventional method..
[0041]
  Claim 3When the substrate development processing apparatus according to the invention is used,Claim 1Since the development processing method according to the present invention can be suitably implemented, the above-described effect of the invention according to claim 1 can be obtained with certainty.
[0042]
  Claim 4In the development processing apparatus according to the invention, since the contact time between the resist film and the developer can be made substantially equal over the entire surface of the substrate, even if the development time is shorter than before, the dissolved state of the soluble portion of the resist film Can be the same over the entire surface of the substrate.
[0043]
  Claim 5In the development processing apparatus according to the present invention, slit scan development is performed, and the contact time between the resist film and the developer can be made equal over the entire surface of the substrate. The dissolved state of the soluble part can be made the same over the entire surface of the substrate.
[Brief description of the drawings]
FIG. 1 is a schematic perspective view showing an example of the configuration of a development processing apparatus used for carrying out a substrate development processing method according to the present invention.
FIG. 2 is a partial enlarged cross-sectional view schematically showing the progress of dissolution reaction in a soluble portion of the resist film when the exposed resist film formed on the surface of the substrate is developed with a developer.
[Figure 3] DevelopmentChanges in reflected light intensity when light is applied to the resist film surface during processingFIG.
[Explanation of symbols]
W substrate
1 resist film
2 soluble part
3 Insoluble parts
4 Boundary line between exposed and unexposed areas (boundary line between soluble and insoluble parts)
5 Bottom of the soluble part
10 Spin chuck
12 Rotating spindle
14 Spin motor
16 Developer discharge nozzle
18 Pure water discharge nozzle
20 Developer supply port of developer discharge nozzle
22 Developer supply pipe
24, 30 Open / close control valve
26 Pure water supply port of pure water discharge nozzle
28 Pure water supply pipe
32 Reflected light intensity measurement head
34 Controller
36 Microcomputer

Claims

In the substrate development processing method of developing a resist film by supplying a developing solution to the resist film after exposure formed on the surface of the substrate,
During the development process, the surface of the resist film is irradiated with light, the intensity of the reflected light is continuously measured, and the development reaction is terminated when the amplitude of the waveform curve indicating the change in the reflected light intensity becomes zero. A development processing method for a substrate, characterized by comprising:

In the substrate development processing method of developing a resist film by supplying a developing solution to the resist film after exposure formed on the surface of the substrate,
While developing the resist film, the surface of the resist film is irradiated with light and the intensity of the reflected light is continuously measured, and a waveform curve indicating the change in the reflected light intensity is obtained in advance. A development processing method for a substrate, characterized in that the development reaction is terminated when the amplitude becomes zero .

A substrate holding means for holding the substrate on which the resist film after exposure is formed on the surface in a horizontal posture;
Developer discharge means for discharging the developer onto the substrate held by the substrate holding means;
Pure water discharge means for discharging pure water onto the substrate held by the substrate holding means;
In a substrate development processing apparatus comprising:
A measuring means for irradiating the surface of the resist film formed on the surface of the substrate with light and continuously measuring the intensity of the reflected light;
Based on the measurement result by the measuring means, the time point when the amplitude becomes 0 in the waveform curve indicating the change in reflected light intensity is determined, and at that time, the discharge of pure water from the pure water discharge means is started to develop. Control means for controlling to terminate the reaction;
A development processing apparatus for a substrate, further comprising:

4. The development processing apparatus for a substrate according to claim 3, wherein the pure water discharge means has the same configuration as the developer discharge means and operates in the same manner .

The developer discharge means includes a developer discharge nozzle that has a slit-shaped discharge port on a lower end surface and discharges the developer from the slit-shaped discharge port onto the substrate while moving in a horizontal direction relative to the substrate. Configured,
The pure water discharge means has a slit-like discharge port on the lower end surface, and moves from the slit-like discharge port to the substrate while moving in the horizontal direction relative to the substrate and in the same direction as the developer discharge nozzle at the same speed. The substrate development processing apparatus according to claim 4, comprising a pure water discharge nozzle for discharging pure water into the substrate.