JP3992894B2 - Cleaning device - Google Patents

Description

【００１０】
一方、例えば１８５ｎｍ程度の波長ν₁ を有する紫外線は、光子エネルギーが強く、被処理部位に存在する有機物の分子結合を切断すると考えられ、式（２）にＣ_m'Ｈ_n'Ｏ_k'で示すこの切断された分子に、上記の非常に酸化力の強い励起酸素原子が反応して、ＣＯ，ＣＯ₂ ，Ｈ₂Ｏ のようにガス状となり、飛散除去可能となる。
【化２】

【００１１】
上記のように、酸素濃度を設定することにより、
ａ）被処理部位近傍に到達するまでに吸収等による紫外線の減衰を低減する。
ｂ）被処理部位近傍において、有機物と反応して飛散除去可能とする活性酸素を充分に発生させる。
ｃ）被処理部位に到達した際において、有機物の分子結合を切断するに充分な紫外線照度，エネルギーを確保する。
という、条件を満たすことができる。
【００１２】
本発明のＵＶ処理方法においては、前記紫外線のピーク波長が１７２ｎｍ付近に設定され、前記被処理部位表面における紫外線の照度が、２．０ｍＷ／ｃｍ² 以上に設定されることが望ましく、これにより、被処理物の被処理部位において、有機物分解等の処理に必要で、かつ処理時間を充分短縮可能な紫外線のエネルギー、照度等の強度状態を維持することが可能となる。
【００１３】
また、本発明の洗浄方法において、不活性ガスにより酸素分圧が２０Ｐａないし１５ｋＰａの範囲に設定された洗浄ガスを被洗浄物の被洗浄部位に供給し、該被洗浄部位に紫外線を照射することにより、大気圧中において酸素等による照射された紫外線の減衰防止を図ることができるので、被処理物（被洗浄物）の被処理部位（被洗浄部位）において、有機物等の汚れを分解洗浄する洗浄処理が所定の時間内で充分な効果を奏するレベルに、紫外線強度を維持することが可能となる。ここで、洗浄効果の充分な程度は、後述するように、例えば有機物洗浄において被洗浄部位における水分との接触角の測定によりおこなうことができる。
【００１４】
本発明の洗浄方法において、前記不活性ガスが、窒素ガス、Ｈｅ，Ｎｅ，Ａｒ，Ｘｅなどの希ガス、好ましくは窒素ガスである手段を採用することにより、照射された紫外線の減衰を防止することができ、さらに、これを低コストにおこなうことができるので、洗浄処理において被処理部位における充分な紫外線照度を大気圧中において維持することが可能となる。
【００１５】
本発明の洗浄方法において、前記紫外線のピーク波長が２５４ｎｍ未満であること、より好ましくは、前記紫外線のピーク波長が１７２ｎｍ付近であることにより、被処理物の被処理部位において、有機物分解等の処理に必要で、かつ処理時間を充分短縮可能な紫外線のエネルギー、照度等の強度状態を維持することがができる。ここで、前記紫外線のピーク波長が２５４ｎｍ以上であると、洗浄処理に必要なエネルギーを得ることができず、被洗浄物の被洗浄部位において、有機物等の汚れを充分に分解洗浄することができず、好ましくない。
【００１６】
さらに、本発明の洗浄方法において、前記被洗浄部位表面における紫外線の照度が、２．０ｍＷ／ｃｍ² 以上に設定されることにより、有機物等の汚れを分解洗浄する洗浄処理が所定の時間内で充分な効果を奏することができる。前記被洗浄部位表面における紫外線の照度が、２．０ｍＷ／ｃｍ² 以下に設定された場合には、被洗浄部位において、充分な洗浄効果を得ることができず、好ましくない。
【００１７】
本発明の洗浄方法において、前記被洗浄部位の洗浄後、この被洗浄部位を洗浄した洗浄処理ガスを前記被洗浄部位から吸引除去することにより、紫外線照射によって発生したオゾン、および、分解された有機物等から発生したガスを吸引し、これらが拡散することを防止できる。また、洗浄ガスを供給するとともに洗浄処理ガスを吸引することにより、被洗浄部位における酸素濃度等、ガス雰囲気の制御をより容易におこなうことが可能となる。
【００１８】
本発明の洗浄装置においては、大気圧中において、被洗浄物の被洗浄部位付近における酸素分圧を２０Ｐａないし１５ｋＰａの範囲に設定する洗浄ガス供給手段と、前記被洗浄部位に紫外線を照射する紫外線光源とを具備し、前記洗浄ガス供給手段により、洗浄ガスを被洗浄物の被洗浄部位に供給して、該被洗浄部位付近における酸素分圧を上記の範囲に設定した状態で、紫外線光源により、前記被洗浄部位に紫外線を照射することにより、被洗浄物の被洗浄部位の有機物の汚れ、有機物のパーティクル等を分解洗浄する。この際、被処理部位以外の部位で酸素による紫外線吸収等の影響を低減し、被処理部位における充分な洗浄処理を短時間におこなうことが可能となる。
【００１９】
本発明において前記洗浄ガス供給手段が、不活性ガスを前記被洗浄部位近傍に噴出する不活性ガス供給部を有し、洗浄ガスとして、窒素ガス、希ガス等の不活性ガスを前記被洗浄部位近傍に直接噴出して、この被洗浄部位近傍の酸素濃度を上記範囲に設定することができる。これにより、窒素ガス等の不活性ガス供給手段のみにより、上記酸素濃度範囲設定が可能となるとともに、
ａ）被洗浄部位近傍に到達するまでに吸収等による紫外線の減衰を低減する。
ｂ）被洗浄部位近傍において、有機物と反応して飛散除去可能とする活性酸素を充分に発生させる。
ｃ）被洗浄部位に到達した際において、有機物の分子結合を切断するに充分な紫外線照度，エネルギーを確保する。
という、条件を満たすことが可能となる。
【００２０】
また、本発明において、前記紫外線光源が、キセノンエキシマ光源とされることにより、洗浄効果の高い、ピーク波長１７２ｎｍの紫外線を洗浄処理に使用することが可能となる。
【００２１】
本発明の洗浄装置において、前記被洗浄部位近傍からこの被洗浄部位を洗浄した洗浄処理ガスを吸引除去する吸引除去手段が設けられることにより、紫外線照射によって発生したオゾン、および、分解された有機物等から発生したガスを吸引し、これらが拡散することを防止できる。また、洗浄ガスを供給するとともに洗浄処理ガスを吸引することにより、被洗浄部位における酸素濃度等、ガス雰囲気の制御をより容易におこなうことが可能となる。
【００２２】
本発明の洗浄装置において、前記紫外線光源が２．０ｍＷ／ｃｍ² 以上の出力を有し、かつ、前記被洗浄部位と前記紫外線光源との距離が、１ｍｍないし１０ｍｍの範囲に設定されることにより、上記の洗浄効果を充分得る紫外線強度を維持することが可能となるとともに、基板等の被洗浄物が前記紫外線光源等に接触することが防止できる。前記被処理部位と前記紫外線光源との距離が１ｍｍないし３ｍｍとなる場合には、被洗浄物のそり、うねりを矯正する機能を有する。
【００２３】
さらに、本発明の洗浄装置において、前記被洗浄部位と前記紫外線光源との距離調整をおこなう距離調整手段を有することにより、被洗浄部位における酸素濃度等、ガス雰囲気の制御をより容易におこなうことが可能となるとともに、基板等の被洗浄物が前記紫外線光源等に接触することの防止をより容易にすることができる。
【００２４】
【発明の実施の形態】
［第１の実施の形態］
以下、本発明に係るＵＶ処理方法ならびに洗浄方法、および洗浄装置の第１実施形態を、図面に基づいて説明する。
図１は本実施の形態の洗浄装置を示す斜視図、図２は図１のII−II線に沿う断面図、図３は図１の洗浄装置を基板との対向面側から見た平面図である。本実施の形態の洗浄装置は、例えば矩形のガラス基板（被洗浄物）の表面を洗浄する際に用いられるものである。
図１ないし図３において、符号１は、洗浄装置（紫外線洗浄用ノズル）である。
【００２５】
本実施形態の紫外線洗浄用ノズル１は、図１ないし図３に示すように、ともに細長い箱状の洗浄ガス供給ノズル２と洗浄処理ガス排出ノズル３と紫外線照射部４とを有し、これらが、紫外線照射部４を洗浄ガス供給ノズル２と洗浄処理ガス排出ノズル３とが挟持した状態に、かつ、基板表面に沿う方向に隣接並置されている。洗浄ガス供給ノズル２は、基板（被洗浄物）表面に向けて洗浄ガスを噴出するための多数の貫通孔を有するものであり、紫外線照射部４は、基板の被洗浄部位に紫外線を照射する機能を有するものであり、洗浄処理ガス排出ノズル３は、紫外線照射により基板表面から発生した洗浄処理ガスを基板表面から排出するための多数の貫通孔を有するものである。
【００２６】
洗浄ガス供給ノズル２においては、図２に示すように、箱状のケーシング２１の内部に、多数の貫通孔を有する多孔質材２２が収容・固定されている。この多孔質材２２は、使用時に基板Ｋに対向するケーシング２１の一面を覆うように収容・固定されるとともに、ケーシング２１の内部には、洗浄ガスを安定して多孔質材２１面均一に噴出させるために、いわゆる畜圧器となる空間部２４が設けられ、この空間部２４に洗浄ガス供給口２３が連通される。
多孔質材２２には、例えば金属、セラミック等が用いられ、この多孔質材２２の基板Ｋに対向する面は、表面粗さが小さく、うねりが小さいことが望ましい。ケーシング２１には、洗浄ガス供給口２３が設けられ、この洗浄ガス供給口２３には、洗浄ガス供給部５が接続されている。洗浄ガス供給ノズル２は、洗浄ガス供給部５により供給された洗浄ガスを、空間部２４を経由して多孔質材２２の多数の貫通孔を通して噴出させ（図２中に洗浄ガスの流れを実線の矢印で示す）、大気圧における基板Ｋの被洗浄部位近傍の酸素分圧を２０Ｐａないし１５ｋＰａの範囲に設定するものとされる。
【００２７】
洗浄ガス供給部５は、不活性ガスと空気とを混合して洗浄ガスとなし、この洗浄ガスを洗浄ガス供給ノズル２に供給するものとされ、この洗浄ガスが、基板Ｋに噴出した際に大気圧中において酸素分圧が２０Ｐａないし１５ｋＰａの範囲に設定されるよう、不活性ガスと空気との混合を制御する制御部をも含有するものとされる。
ここで、不活性ガスとしては、窒素ガス、Ｈｅ，Ｎｅ，Ａｒ，Ｘｅなどの希ガス等、紫外線に対して透過的であるガス、つまり紫外線に対して透明なガスが採用され、コスト等の面から、好ましくは、窒素ガスとされる。
洗浄ガス供給ノズル２および、洗浄ガス供給部５は、洗浄ガス供給手段を構成している。
【００２８】
紫外線照射部４は、箱状のケーシング４１内部の封止部４４に、このケーシング４１の長手方向に沿って延在する紫外線光源４２を有するものとされる。このケーシング４１は、封止部４４の紫外線光源４１周辺に窒素ガスが充填された状態で、使用時に基板Ｋと対向する該ケーシング４１の一面が石英ガラス４３により密閉されている。
この紫外線光源４２は、照射される紫外線のピーク波長が２５４ｎｍ以下とされ、例えば、Ｘｅ₂ が石英ガラス等の誘電体からなる発光管に封止されて、これに金属電極から高周波電力を供給されることにより放電プラズマｓが発生して発光する、キセノンエキシマ光源（誘電体バリア放電エキシマランプ）とされ、キセノンダイマーからのピーク波長１７２ｎｍの紫外線を照射するものとされる。
図４は、紫外線光源４２から放射される紫外線の分光分布図である。
ここで、紫外線光源４２から照射される紫外線は、図４に示すように、ピーク波長ν₃ が１７２ｎｍであり、その半値幅は１４ｎｍのものとされる。さらに、紫外線光源４２が２．０ｍＷ／ｃｍ² 以上の出力を有するとともに、この紫外線光源４２の発光長さは、図３に示すようにＬ₁ に設定される。
【００２９】
ここで、前記紫外線のピーク波長が２５４ｎｍ以上であると、洗浄処理に必要な光子エネルギーを得ることができず、基板Ｋの被洗浄部位において、後述するように励起酸素原子の生成と、有機物の分子結合の切断とを充分おこなうことができず、有機物の分解洗浄が不充分になる可能性があり、好ましくない。
また、この発光光源の長さＬ₁ は、最大寸法が９６０ｍｍ〜１５００ｍｍ程度に設定される基板Ｋの幅寸法に対応して、１〜１．５倍程度に設定される。
この発光光源の長さＬ₁ が基板Ｋの幅より小さく設定された場合には、一回の走査で処理を終了することができず、処理を複数回繰り返すことが必要であるが、この場合、各処理が均一におこなわれない可能性があり、好ましくない。また、発光光源の長さＬ₁ が１５００ｍｍより大きく設定された場合には、基板Ｋの幅寸法以上となり、基板Ｋに照射されず、無駄に発光する部分が生じる可能性があり、この場合、紫外線光源４２の消費電力が発光長さにより規定されるため、ランニングコストが増大して好ましくない。少なくとも基板Ｋの幅と同じかわずかに長い光源を選択することが好ましい。
【００３０】
洗浄処理ガス排出ノズル３は、図２に示すように、洗浄ガス供給ノズル２と略同等の構造とされ、箱状のケーシング３１の内部に、空間部３４を有して多数の貫通孔を有する多孔質材３２が収容、固定されている。ケーシング３１には、洗浄処理ガス排出口３３が設けられ、この洗浄処理ガス排出口３３には、洗浄処理ガス排出部６が接続されている。
【００３１】
洗浄処理ガス排出部６は、その使用時に、基板Ｋの被洗浄部位近傍において紫外線照射により発生したオゾン、および、分解された有機物等から発生したガス等からなる洗浄処理ガスを、洗浄処理ガス排出ノズル３の多孔質材３２の多数の貫通孔を通って洗浄処理ガス排出口３３を介して吸引除去する（図２中に洗浄処理ガス等の流れを実線の矢印で示す）とともに、この洗浄処理ガスの吸引除去により、基板Ｋの被洗浄部位近傍における酸素分圧の制御を制御する制御部をも有するものとされる。
洗浄処理ガス排出ノズル３および、洗浄処理ガス排出部６は、吸引除去手段を構成している。
【００３２】
紫外線洗浄用ノズル１は、図２に示すように、使用時に基板Ｋと対向する側の面が面一となるように、洗浄ガス供給ノズル２と洗浄処理ガス排出ノズル３と紫外線照射部４とが固定されている。
ここで、洗浄ガス供給ノズル２と洗浄処理ガス排出ノズル３と紫外線照射部４とは、それぞれのケーシング２１，３１，４１どうしがネジ等の固定部により固定されている。
【００３３】
また、このとき、図２に示すように、使用状態における基板Ｋの前記被洗浄部位と前記紫外線光源４２との距離Ｌ₃ が、１ｍｍないし１０ｍｍの範囲に設定され、かつ、前記被洗浄部位における紫外線の照度が、２．０ｍＷ／ｃｍ² 以上に設定されるとともに、紫外線洗浄用ノズル１と基板Ｋとの距離Ｌ₂ は、最大寸法が９６０ｍｍ〜１５００ｍｍ程度に設定される基板Ｋの寸法に対応して考慮される基板Ｋのそり、うねり等の変形に対応して、基板Ｋと紫外線洗浄用ノズル１とが接触しないように設定される。
ここで、使用状態における基板Ｋの前記被洗浄部位と前記紫外線光源４２との距離Ｌ₃ が、１ｍｍ以下に設定された場合には、基板Ｋと紫外線洗浄用ノズル１とが接触する可能性があり、好ましくない。また、使用状態における基板Ｋの前記被洗浄部位と前記紫外線光源４２との距離Ｌ₃ が、１０ｍｍ以上に設定された場合には、基板Ｋの被洗浄部位における紫外線強度が低下し、分解洗浄に必要な紫外線照度を維持できない可能性があり好ましくない。
同様に、前記被洗浄部位における紫外線の照度が、２．０ｍＷ／ｃｍ² 以下に設定された場合には、紫外線照度が不足し、充分な分解洗浄処理が行えない可能性があり、好ましくない。
【００３４】
上記構成の紫外線洗浄用ノズル１は、洗浄ガス供給ノズル２と洗浄処理ガス排出ノズル３と紫外線照射部４とが基板Ｋ表面に沿う方向に隣接並置されており、使用時には基板Ｋ表面が洗浄ガス供給ノズル２，紫外線照射部４，洗浄処理ガス排出ノズル３の順に対向する方向（図２においてノズル１が右から左、基板Ｋが左から右に移動する方向）に紫外線洗浄用ノズル１と基板Ｋとを相対移動させて基板Ｋの洗浄処理（ＵＶ処理）を行う。
ここで、この紫外線洗浄用ノズル１において、紫外線洗浄用ノズル１と基板Ｋとが相対移動した場合に、前記基板Ｋの被洗浄部位と前記紫外線光源４２との距離Ｌ₃ が、１ｍｍないし１０ｍｍの範囲に維持されるよう、紫外線洗浄用ノズル１と基板Ｋとの相対位置調整をおこなう制御部を有する距離調整手段が設けられる。
【００３５】
このような紫外線洗浄用ノズル１による洗浄方法においては、まず、基板Ｋ表面の上方に距離Ｌ₂ 離間して配置された洗浄ガス供給ノズル２が通過すると、噴出する洗浄ガスにより基板Ｋ表面の被洗浄部位近傍において、大気圧中における酸素分圧が２０Ｐａないし１５ｋＰａの範囲に設定される。次に、酸素分圧がこの範囲とされた基板Ｋ表面の被洗浄部位に向けて紫外線照射部４の紫外線光源４２からピーク波長が１７２ｎｍ付近の紫外線が照射されることにより、基板Ｋ表面の被洗浄部位に付着あるいは汚染している有機物等が分解される。そして、紫外線照射によって発生したオゾン、および、分解された有機物等から発生したガスを含有する洗浄処理ガスが、洗浄処理ガス排出ノズル３の多孔質材３２の多数の貫通孔を通じて基板Ｋ表面から吸引、排出される。このようにして、基板Ｋ全体に対して紫外線洗浄用ノズル１と基板とを相対移動させることにより、基板Ｋ表面の全域を洗浄処理することができる。
【００３６】
ここで、紫外線照射による有機物等の分解について説明する。
紫外線による洗浄処理においては、例えば、紫外線光源４２から照射される紫外線は、ピーク波長ν₃ が１７２ｎｍであり、その半値幅は１４ｎｍである。この波長ν₃ を有する紫外線により、次のプロセスによって分解がおこなわれる。１７２ｎｍ程度の波長ν₃ を有する紫外線、つまり、１７５ｎｍよりも短い波長を有する光は、直接、大気中の酸素に吸収され、励起酸素原子（式（３）にＯ（１Ｄ）で示す；活性酸素，oxygen radical）が生成する。
【化３】

【００３７】
１７２ｎｍとされる波長ν₃ を有する紫外線は、前述した１８５ｎｍ，２５４ｎｍとされる波長ν₁ ，ν₂ を有する紫外線と同様に、空気中の酸素Ｏ₂ に吸収されてオゾンＯ₃ を発生し、さらに、このオゾンＯ₃ から励起酸素原子（式（４）にＯ（１Ｄ）で示す）を生成する経路も有する。
【化４】

【００３８】
この１７２ｎｍとされる波長ν₃ を有する紫外線は、前述した１８５ｎｍ，２５４ｎｍ付近とされる波長ν₁ ，ν₂ を有する紫外線よりも光子のエネルギーが強く、より容易に、被処理部位に存在する有機物の分子結合を切断すると考えられ、式（５）にＣ_m'Ｈ_n'Ｏ_k'で示すように、この切断された分子に、上記の非常に酸化力の強い励起酸素原子が反応して、ＣＯ，ＣＯ₂ ，Ｈ₂Ｏ のようにガス状となり、飛散除去可能となる。
【化５】

【００３９】
このように、前述した１８５ｎｍ，２５４ｎｍとされる波長ν₁ ，ν₂ を有する紫外線に比べ、キセノンエキシマ光源からの１７２ｎｍとされる波長ν₃ を有する紫外線は、生成される励起酸素原子が多く、かつ、有機物の分子結合をより容易に切断することができるため、洗浄速度を高めることが可能となり、処理時間の短縮を図ることが可能となる。
【００４０】
本実施形態の紫外線洗浄用ノズル１による洗浄処理においては、洗浄ガス供給ノズル２から洗浄ガスを噴出し、基板Ｋの被洗浄部位近傍を大気圧中において、酸素分圧を２０Ｐａないし１５ｋＰａの範囲に設定した洗浄ガス雰囲気とすることにより、紫外線光源４２から照射される紫外線に対して、透明な不活性ガスにより酸素分圧を制御するので、紫外線の余分な吸収を防止することができる。同時に、酸素分圧を制御することにより、紫外線照射により発生し、分子結合の切断された有機物と反応する励起酸素原子を、分解洗浄に充分必要なだけ発生することが可能となる。
したがって、
ａ）被洗浄部位近傍に到達するまでに吸収等による紫外線の減衰を低減する。
ｂ）被洗浄部位近傍において、有機物と反応して飛散除去可能とする励起酸素原子を充分に発生させる。
ｃ）被洗浄部位に到達した際において、有機物の分子結合を切断するに充分な紫外線照度ーを確保する。
という、条件を満たすことが可能となる。
また、このような、酸素分圧の制御を、洗浄ガス供給手段および吸引除去手段の制御部により大気圧中でおこなうことができ、真空室等を設ける必要がなく、低コストで提供することが可能となる。
【００４１】
本実施形態においては、前記紫外線のピーク波長が１７２ｎｍ付近に設定されることにより、基板Ｋの被処理部位において、有機物の分子結合切断および充分な励起酸素原子の発生に必要な光子エネルギーを有するため、処理時間を充分短縮することが可能となる。
また、本実施形態においては、前記被処理部位表面における紫外線の照度が、２．０ｍＷ／ｃｍ² 以上に設定されることにより、有機物の分子結合切断および充分な励起酸素原子の発生に必要な照度を有するため、処理時間を充分短縮することが可能となる。
本実施形態においては、前記紫外線光源４２が、キセノンエキシマ光源とされることにより、安価にかつ簡便に、前記紫外線のピーク波長を１７２ｎｍ付近に設定し、かつ、前記被処理部位表面における紫外線の照度を、２．０ｍＷ／ｃｍ² 以上に設定することができ、洗浄効果を高めることができる。
【００４２】
本実施形態において、前記紫外線光源４２が２．０ｍＷ／ｃｍ² 以上の出力を有し、かつ、基板Ｋの被洗浄部位と前記紫外線光源４２との距離が、１ｍｍないし１０ｍｍの範囲に設定されることにより、後述する洗浄効果を充分得る紫外線強度を維持することが可能となるとともに、基板Ｋの被洗浄物が前記紫外線光源４２および紫外線洗浄用ノズル１に接触することが防止できる。
【００４３】
また、この紫外線洗浄用ノズル１において、紫外線洗浄用ノズル１と基板Ｋとが相対移動した場合に、前記基板Ｋの被洗浄部位と前記紫外線光源４２との距離Ｌ₃ が、１ｍｍないし１０ｍｍの範囲に維持されるよう、紫外線洗浄用ノズル１と基板Ｋとの相対位置調整をおこなう距離調整手段を有することにより、被洗浄部位における酸素分圧等、洗浄ガス雰囲気の制御をより容易におこなうことが可能となるとともに、基板Ｋの被洗浄物が前記紫外線光源４２および紫外線洗浄用ノズル１に接触することをより容易に防止することができる。
【００４４】
本実施形態において、前記被洗浄部位の洗浄後、この被洗浄部位を洗浄した洗浄処理ガスを前記被洗浄部位から吸引除去することにより、残った洗浄ガス、紫外線照射によって発生したオゾン、および、分解された有機物等から発生したガス等を吸引し、これらが拡散することを防止できる。また、洗浄ガスを供給するとともに洗浄処理ガスを吸引することにより、被洗浄部位における酸素濃度等、ガス雰囲気の制御をより容易におこなうことが可能となる。
ことができる。
【００４５】
ここで、基板Ｋの被処理部位（被洗浄部位）において、有機物の汚れを分解洗浄する洗浄処理が所定の時間内で充分な効果を奏するレベルにあることは、例えば基板Ｋ表面の被洗浄部位における水分との接触角の測定によりおこなうことができる。
【００４６】
図５，図６は洗浄処理における被洗浄部位近傍の酸素分圧と洗浄処理後における基板Ｋ表面の接触角の関係を示すグラフ、図７は接触角を説明するための模式図である。
接触角とは、図７に示すように、基板Ｋ上の水滴Ｗ表面の接面が、基板Ｋ表面となす角θを意味し、例えば、基板Ｋ表面に有機物の付着等による汚れがあった場合には、有機物の疎水性によりこの接触角θが大きくなるため、基板Ｋ表面の有機物残留度、つまり、洗浄状態の指標として用いられる。
【００４７】
本実施形態のように、例えば、洗浄処理時間を１０秒として、基板Ｋの被洗浄部位近傍の酸素分圧を２０Ｐａないし１５ｋＰａの範囲に設定した場合には、基板Ｋの前記被洗浄部位と前記紫外線光源４２との距離Ｌ₃ が１ｍｍに設定された図５の結果、および、距離Ｌ₃ が５ｍｍに設定された図６の結果、いずれの場合においても、充分な洗浄効果を得ることができる。ここで、充分な洗浄効果を得るとは、例えば６secないし１０sec とされる所定の洗浄処理時間において、接触角θが１０度以下、好ましくは５度以下の状態になることを意味している。
【００４８】
［第２の実施の形態］
以下、本発明に係るＵＶ処理方法ならびに洗浄方法、および洗浄装置の第２実施形態を、図面に基づいて説明する。
図８は本実施の形態の洗浄装置（紫外線洗浄用ノズル）を示す斜視図、図９は図８のIX−IX線に沿う断面図、図１０は図８の洗浄装置を基板との対向面側から見た平面図である。第１の実施の形態の洗浄装置（紫外線洗浄用ノズル）が基板表面側のみの洗浄ガス制御をおこなうものであったのに対し、本実施の形態の洗浄装置（紫外線洗浄用ノズル）は、基板の裏面側からの洗浄ガス制御を同時になし得るものである。
【００４９】
本実施形態において、図１ないし図３に示す第１実施形態と異なる部分は、基板Ｋの裏面側に対応する位置に、洗浄ガス供給ノズル（下）７と洗浄処理ガス排出ノズル（下）８とを配置した点であり、図１ないし図３に示す第１実施形態と略同等の構成要素には、同一符号を付して説明を省略する。
【００５０】
洗浄ガス供給ノズル（下）７は、図９に示すように、洗浄ガス供給ノズル２と略同様に、箱状のケーシング７１の内部に、多数の貫通孔を有する多孔質材７２が収容・固定されている。この多孔質材７２は、使用時に基板Ｋに対向するケーシング７１の一面を覆うように収容・固定されるとともに、ケーシング７１の内部には、洗浄ガスを安定して多孔質材７１面均一に噴出させるための空間部７４が設けられ、この空間部７４に洗浄ガス供給口７３が連通される。
多孔質材７２には、例えば金属、プラスティック、セラミック等が用いられ、この多孔質材７２の基板Ｋに対向する面は、表面粗さが小さく、うねりが小さいことが望ましい。
ケーシング７１には、洗浄ガス供給口７３が設けられ、この洗浄ガス供給口７３には、洗浄ガス供給部５’が接続されている。洗浄ガス供給ノズル（下）７は、洗浄ガス供給部５’により供給された洗浄ガスを、空間部７４を経由して多孔質材７２の多数の貫通孔を通して噴出させ（図９中に洗浄ガスの流れを実線の矢印で示す）、大気圧における基板Ｋの被洗浄部位近傍の酸素分圧を２０Ｐａないし１５ｋＰａの範囲に設定する洗浄ガス供給手段を構成するものとされる。
洗浄ガス供給部５’は、不活性ガスと空気とを混合して洗浄ガスとなし、この洗浄ガスを洗浄ガス供給ノズル（下）７に供給するものとされる。図９においては、洗浄ガス供給部５’を洗浄ガス供給ノズル２に接続される洗浄ガス供給部５と別構成のように記載したが、同一の構成とすることも可能である。
【００５１】
洗浄処理ガス排出ノズル（下）８は、図９に示すように、洗浄ガス供給ノズル（下）７と略同等の構造とされ、箱状のケーシング８１の内部に、空間部８４を有して多数の貫通孔を有する多孔質材８２が収容・固定されている。ケーシング８１には、洗浄処理ガス排出口８３が設けられ、この洗浄処理ガス排出口８３には、洗浄処理ガス排出部６’が接続されており、吸引除去手段を構成するものとされる。
洗浄処理ガス排出部６’は、その使用時に、基板Ｋの被洗浄部位近傍において洗浄処理ガスを吸引除去する（図９中に洗浄処理ガス等の流れを実線の矢印で示す）ものとされる。図９においては、洗浄処理ガス排出部６’を洗浄処理ガス排出ノズル３に接続される洗浄処理ガス排出部６と別構成のように記載したが、同一の構成とすることも可能である。
【００５２】
洗浄ガス供給ノズル（下）７と洗浄処理ガス排出ノズル（下）８とは、洗浄ガス供給ノズル２と洗浄処理ガス排出ノズル３と紫外線照射部４とに対して、使用状態において基板Ｋと挟んで対向する位置に、多孔質材７２，８２を多孔質材２２，３２，石英ガラス４３に対向して配置される。この洗浄ガス供給ノズル（下）７と洗浄処理ガス排出ノズル（下）８とは、多孔質材７２，８２が面一となるように固定されており、図１０に示すように、洗浄ガス供給ノズル（下）７と洗浄処理ガス排出ノズル（下）８との基板Ｋ移動方向の長さ寸法Ｌ₅ が、図２に示す洗浄ガス供給ノズル２と洗浄処理ガス排出ノズル３と紫外線照射部４との基板Ｋ移動方向の長さ寸法Ｌ₅ と略等しくなるように設定されている。ここで、洗浄ガス供給ノズル（下）７と洗浄処理ガス排出ノズル（下）８との基板Ｋ移動方向の長さ寸法は、図２に示す洗浄ガス供給ノズル２と洗浄処理ガス排出ノズル３と紫外線照射部４との基板Ｋ移動方向の長さ寸法Ｌ₅ より大きく設定することも可能である。
【００５３】
本実施の形態の紫外線洗浄用ノズル１は、図８ないし図１０に示すように、第１の実施の紫外線洗浄用ノズル１の下側に洗浄ガス供給ノズル（下）７と洗浄処理ガス排出ノズル（下）８とを配置したものであり、基板Ｋの上側に位置するノズル２，３，４と、基板Ｋの下側に位置するノズル７，８とは、別体として独立に移動するようにしても良いし、任意の方法で連結しておき、一緒に移動する構成としても良い。
ここで、図１ないし図３に示す第１実施形態と同様に、洗浄ガス供給ノズル（下）７および洗浄処理ガス排出ノズル（下）８と基板Ｋの被洗浄部位との距離Ｌ₄ の調整をおこなう、つまり相対位置調整をおこなう距離調整手段が設けられる。
【００５４】
これにより、基板Ｋが、ノズル２，３，４とノズル７，８との間に位置しない状態、つまり洗浄処理をおこなう前に、このノズル２，３，４とノズル７，８との間の空間を、前述の洗浄ガス雰囲気に設定することが可能であり、かつ、この付近の酸素分圧の設定をより容易におこなうことが可能となる。したがって、基板Ｋの被洗浄部位近傍の酸素分圧の設定をより容易におこなうことができ、洗浄効率の向上を図ることが可能となる。
さらに、基板Ｋと、ノズル２，３，４およびノズル７，８との間の距離設定をより容易に制御することが可能となる。
また、下側のノズル７，８を設けたことにより、洗浄処理ガスの拡散を防止し、オゾン等の排出をより容易におこなうことができる。
【００５５】
［第３の実施の形態］
以下、本発明に係るＵＶ処理方法ならびに洗浄方法、および洗浄装置の第３実施形態を、図面に基づいて説明する。
本実施の形態は本発明の乾燥用ノズルを具備した洗浄装置の一例である。図１１は本実施の形態の洗浄装置５１の概略構成を示す図であって、例えば数百ｍｍ角程度の大型のガラス基板（以下、単に基板という）を枚葉洗浄するための装置である。
図中符号５２は洗浄部、５３はステージ（基板保持手段）、１、５５、５６、４９は洗浄用ノズル、５０は乾燥用ノズル、５７は基板搬送ロボット、５８はローダカセット、５９はアンローダカセット、６０は水素水・オゾン水生成部、６１は洗浄液再生部、Ｋは基板である。
【００５６】
図１１に示すように、装置上面中央が洗浄部５２となっており、基板Ｋを保持するステージ５３が設けられている。ステージ５３には、基板Ｋの形状に合致した矩形の段部が設けられ、この段部上に基板Ｋが嵌め込まれて、基板Ｋの表面とステージ５３の表面が面一状態でステージ５３に保持されるようになっている。また、段部の下方には空間部が形成され、空間部にはステージ５３の下方から基板昇降用シャフトが突出している。基板昇降用シャフトの下端にはシリンダ等のシャフト駆動源が設けられ、後述する基板搬送ロボット５７による基板Ｋの受け渡しの際にシリンダの作動により基板昇降用シャフトが上下動し、シャフトの上下動に伴って基板Ｋが上昇または下降するようになっている。なお、ステージ中央に設けられた孔から基板Ｋの裏面洗浄用のノズルが突出しており、本装置では表面側を主に洗浄するが、同時に裏面側も軽く洗浄できるようになっている。
【００５７】
ステージ５３を挟んで対向する位置に一対のラックベース６２が設けられ、これらラックベース６２間に洗浄用ノズル１，５５，５６，４９が架設されている。洗浄用ノズルは並列配置された４本のノズルからなり、各洗浄用ノズル１，５５，５６，４９が異なる洗浄方法により洗浄を行うものとなっている。本実施の形態の場合、これら４本のノズルは、洗浄ガス供給手段（図示略）から基板Ｋに洗浄ガスを供給するとともに紫外線ランプ４２から紫外線を照射することによって主に有機物を分解除去する上記実施の形態の紫外線洗浄用ノズル１、オゾン水を供給しつつ超音波素子６３により超音波振動を付与して洗浄するオゾン水超音波洗浄用ノズル５５、水素水を供給しつつ超音波素子６３により超音波振動を付与して洗浄する水素水超音波洗浄用ノズル５６、純水を供給してリンス洗浄を行う純水リンス洗浄用ノズル４９、である。これら４本のノズルが基板Ｋの上方で基板Ｋとの間隔を一定に保ちながらラックベース６２に沿って順次移動することにより、基板Ｋの被洗浄面全域が４種類の洗浄方法により洗浄される構成となっている。さらに、同一のラックベース６２間に乾燥用ノズル５０が架設されており、洗浄後の濡れた基板Ｋがこの乾燥用ノズル５０によって乾燥される構成となっている。
なお、図１１においては、紫外線洗浄用ノズル１を１本の棒状に示したが、実際には前述の第１，第２の実施形態における構成と同等の構成とされ、洗浄ガス供給ノズル２，洗浄処理ガス排出ノズル３，紫外線照射部４等を含んでいる。
【００５８】
各ノズルの移動手段としては、各ラックベース６２上のリニアガイドに沿って水平移動可能とされたスライダがそれぞれ設けられ、各スライダの上面に支柱がそれぞれ立設され、これら支柱に各洗浄用ノズル１，５５，５６，４９および乾燥用ノズル５０の両端部が固定されている。各スライダ上にはモータ等の駆動源が設置されており、各スライダがラックベース６２上を自走する構成となっている。そして、装置の制御部（図示略）から供給される制御信号により各スライダ上のモータがそれぞれ作動することによって、各洗浄用ノズル１，５５，５６，４９および乾燥用ノズル５０が個別に水平移動する構成となっている。また、支柱にはシリンダ（図示略）等の駆動源が設けられ、支柱が上下動することにより各洗浄用ノズル１，５５，５６，４９および乾燥用ノズル５０の高さ、すなわち各洗浄用ノズル１，５５，５６，４９と基板Ｋとの間隔、乾燥用ノズル５０と基板Ｋとの間隔がそれぞれ調整可能となっている。これらは、距離調整手段を構成する。
【００５９】
各洗浄用ノズル５５，５６，４９は、一端に洗浄液を導入するための導入口を有する導入通路と一端に洗浄後の洗浄液を外部へ排出するための排出口を有する排出通路とが形成され、これら導入通路と排出通路とをそれぞれの他端において交差させて交差部が形成されるとともに、この交差部に基板Ｋに向けて開口する開口部が設けられたものであり、プッシュ・プル型ノズル（省流体型ノズル）と呼ばれるものである。この場合、開口部は、洗浄用ノズル５５，５６，４９の並列方向と交差する方向に少なくとも基板Ｋの幅以上の長さに延びている（本実施の形態の場合、１本の洗浄用ノズルにつき、導入通路と排出通路とが交差した交差部および開口部は３組設けられており、３組合わせて開口部が基板Ｋの幅以上の長さに延びている）。排出通路側の圧力制御部に減圧ポンプを用いて、この減圧ポンプで交差部の洗浄液を吸引する力を制御して、開口部の大気と接触している洗浄液の圧力（洗浄液の表面張力と基板Ｗの被洗浄面の表面張力も含む）と大気圧との均衡をとるようになっている。つまり、開口部の大気と接触している洗浄液の圧力Ｐ_w（洗浄液の表面張力と基板Ｋの被洗浄面の表面張力も含む）と大気圧Ｐ_aとの関係をＰ_w≒Ｐ_aとすることにより、開口部を通じて基板Ｋに供給され、基板Ｋに接触した洗浄液は、洗浄用ノズルの外部に漏れることなく、排出通路に排出される。すなわち、洗浄用ノズルから基板Ｋ上に供給した洗浄液は、基板Ｋ上の洗浄液を供給した部分（開口部）以外の部分に接触することなく、基板Ｋ上から除去される。さらに、交差部の上方に基板Ｋに対向するように超音波素子６３が設けられており、基板Ｋが洗浄されている間、洗浄液に超音波が付与されるようになっている。
【００６０】
洗浄部５２の側方に、水素水・オゾン水生成部６０と洗浄液再生部６１とが設けられている。水素水・オゾン水生成部６０には、水素水製造装置６４とオゾン水製造装置６５とが組み込まれている。いずれの洗浄液も、純水中に水素ガスやオゾンガスを溶解させることによって生成することができる。そして、水素水製造装置６４で生成された水素水が、水素水供給配管６６の途中に設けられた送液ポンプ６７により水素水超音波洗浄用ノズル５６に供給されるようになっている。同様に、オゾン水製造装置６５で生成されたオゾン水が、オゾン水供給配管６８の途中に設けられた送液ポンプ６９によりオゾン水超音波洗浄用ノズル５５に供給されるようになっている。なお、純水リンス洗浄用ノズル４９には製造ライン内の純水供給用配管（図示略）から純水が供給されるようになっている。
【００６１】
また、洗浄液再生部６１には、使用後の洗浄液中に含まれたパーティクルや異物を除去するためのフィルタ７０、１７１が設けられている。水素水中のパーティクルを除去するための水素水用フィルタ７０と、オゾン水中のパーティクルを除去するためのオゾン水用フィルタ１７１が別系統に設けられている。すなわち、水素水超音波洗浄用ノズル５６の排出口から排出された使用後の水素水は、水素水回収配管１７２の途中に設けられた送液ポンプ１７３により水素水用フィルタ７０に回収されるようになっている。同様に、オゾン水超音波洗浄用ノズル５５の排出口から排出された使用後のオゾン水は、オゾン水回収配管１７４の途中に設けられた送液ポンプ７５によりオゾン水用フィルタ１７１に回収されるようになっている。
【００６２】
そして、水素水用フィルタ７０を通した後の水素水は、再生水素水供給配管７６の途中に設けられた送液ポンプ７７により水素水超音波洗浄用ノズル５６に供給されるようになっている。同様に、オゾン水用フィルタ１７１を通した後のオゾン水は、再生オゾン水供給配管７８の途中に設けられた送液ポンプ７９によりオゾン水超音波洗浄用ノズル５５に供給されるようになっている。また、水素水供給配管６６と再生水素水供給配管７６は水素水超音波洗浄用ノズル５６の手前で接続され、弁８０によって水素水超音波洗浄用ノズル５６に新しい水素水を導入するか、再生水素水を導入するかを切り換え可能となっている。同様に、オゾン水供給配管６８と再生オゾン水供給配管７８はオゾン水超音波洗浄用ノズル５５の手前で接続され、弁１８１によってオゾン水超音波洗浄用ノズル５５に新しいオゾン水を導入するか、再生オゾン水を導入するかを切り換え可能となっている。なお、各フィルタ７０，１７１を通した後の水素水やオゾン水は、パーティクルが除去されてはいるものの、液中気体含有濃度が低下しているため、配管を通じて再度水素水製造装置６４やオゾン水製造装置６５に戻し、水素ガスやオゾンガスを補充するようにしてもよい。
【００６３】
洗浄部５２の側方に、ローダカセット５８、アンローダカセット５９が着脱可能に設けられている。これら２つのカセット５８、５９は、複数枚の基板Ｋが収容可能な同一の形状のものであり、ローダカセット５８に洗浄前の基板Ｋを収容し、アンローダカセット５９には洗浄済の基板Ｋが収容される。そして、洗浄部５２とローダカセット５８、アンローダカセット５９の中間の位置に基板搬送ロボット５７が設置されている。基板搬送ロボット５７はその上部に伸縮自在なリンク機構を有するアーム１８２を有し、アーム１８２は回転可能かつ昇降可能となっており、アーム１８２の先端部で基板Ｋを支持、搬送するようになっている。
【００６４】
上記構成の洗浄装置５１は、例えば洗浄用ノズル１，５５，５６，４９または乾燥用ノズル５０と基板Ｋとの間隔、洗浄用ノズルまたは乾燥用ノズルの移動速度、洗浄ガスの流量および酸素分圧、洗浄液の流量等、種々の洗浄条件、乾燥条件をオペレータが設定する他は、各部の動作が制御部により制御されており、自動運転する構成になっている。したがって、この洗浄装置５１を使用する際には、洗浄前の基板Ｋをローダカセット５８にセットし、オペレータがスタートスイッチを操作すれば、基板搬送ロボット５７によりローダカセット５８からステージ５３上に基板Ｋが搬送され、ステージ５３上で各洗浄用ノズル１，５５，５６，４９および乾燥用ノズル５０により紫外線洗浄、オゾン水超音波洗浄、水素水超音波洗浄、リンス洗浄、乾燥が順次自動的に行われ、乾燥後、基板搬送ロボット５７によりアンローダカセット５９に収容される。
【００６５】
本実施の形態の洗浄装置５１においては、４本の洗浄用ノズル１，５５，５６，４９の各々が、紫外線洗浄、オゾン水超音波洗浄、水素水超音波洗浄、リンス洗浄といった異なる洗浄方法により洗浄処理する構成であるため、本装置１台で種々の洗浄方法を実施することができる。したがって、例えば、紫外線照射により有機物等を除去洗浄し、そして、水素水超音波洗浄、オゾン水超音波洗浄により微細な粒径のパーティクルを除去し、さらにリンス洗浄で基板表面に付着した洗浄液も洗い流しながら仕上げの洗浄を行う、というように種々の被除去物を充分に洗浄除去することができる。また、本実施の形態の洗浄装置の場合、乾燥用ノズル５０が備えられているため、洗浄、乾燥の一貫処理を自動的に行うことができる。特に、上記実施の形態の紫外線洗浄ノズル１による洗浄処理においては、酸素分圧の設定をおこなうことにより、洗浄時間を短く設定することができ、さらに、従来のオゾン水を使用する有機物分解処理用ノズルのように水分を基板Ｋ表面に接触させる必要がないため、基板Ｋの乾燥を行なう必要がない。そして、本実施の形態の洗浄装置５１によれば、上記実施の形態の紫外線洗浄用ノズル１を具備したことによって、半導体デバイス、液晶表示パネル等をはじめとする各種電子機器の製造ラインに好適な高効率の洗浄装置を実現することができる。
【００６６】
なお、本発明の技術範囲は上記実施の形態に限定されるものではなく、本発明の趣旨を逸脱しない範囲において種々の変更を加えることが可能である。例えば洗浄ガスとして、空気と不活性ガスを混合した後に、洗浄ガス供給ノズル２等に供給する構成としたが、例えば窒素ガスとされる不活性ガスのみを、基板Ｋの被洗浄部位近傍に噴出し、この不活性ガスを、基板Ｋの被洗浄部位近傍に存在する空気と混合することにより、被洗浄部位近傍の酸素分圧を制御する不活性ガス供給部を設けることも可能である。また、この不活性ガス供給部によって、不活性ガスのみを被洗浄部位近傍に噴出すると同時に、基板Ｋの被洗浄部位近傍に比べて、紫外線照射部４近傍の酸素分圧が低い状態に設定し、紫外線照射部４近傍における酸素分子による紫外線吸収をより低減することも可能である。また、不活性ガスと酸素ガスとを混合してまたは直接噴出して酸素分圧の制御をおこなうことも可能である。
【００６７】
【発明の効果】
以上、詳細に説明したように、本発明の洗浄装置によれば、低コストで、酸素分圧の設定をおこない、ＵＶ処理時間を短縮し、充分な分解除去洗浄をおこないつつ紫外線洗浄の作業効率を向上することができるという効果を奏する。
【図面の簡単な説明】
【図１】 本発明に係る洗浄装置の第１実施形態を示す斜視図である。
【図２】 図１のII−II線に沿う断面図である。
【図３】 図１の洗浄装置を示す平面図である。
【図４】 図１の紫外線光源４２から放射される紫外線の分光分布図である。
【図５】 洗浄処理における被洗浄部位近傍の酸素分圧と洗浄処理後における基板Ｋ表面の接触角の関係を示すグラフである。
【図６】 洗浄処理における被洗浄部位近傍の酸素分圧と洗浄処理後における基板Ｋ表面の接触角の関係を示すグラフである。
【図７】 接触角を説明するための模式図である。
【図８】 本発明に係る洗浄装置の第２実施形態を示す斜視図である。
【図９】 図８のIX−IX線に沿う断面図である。
【図１０】 図８の洗浄装置を示す平面図である。
【図１１】 本発明の第３の実施の形態の洗浄装置の概略構成を示す平面図である。
【符号の説明】
Ｋ…基板（被洗浄物）
１…紫外線洗浄用ノズル（洗浄装置）
２…洗浄ガス供給ノズル
３…洗浄処理ガス排出ノズル
４…紫外線照射部
５，５’…洗浄ガス供給部
６，６’…洗浄処理ガス排出部
７…洗浄ガス供給ノズル（下）
８…洗浄処理ガス排出ノズル（下）
４２…紫外線光源[0001]
BACKGROUND OF THE INVENTION
  The present inventionCleaning deviceIn particular, the present invention relates to a technique suitable for use in, for example, UV treatment or cleaning treatment of a substrate or the like in a manufacturing process of a semiconductor device, a liquid crystal display panel, or the like, by decomposing organic matter by irradiating ultraviolet rays.
[0002]
[Prior art]
In the field of electronic devices such as semiconductor devices and liquid crystal display panels, a step of cleaning a semiconductor substrate or glass substrate, which is a substrate to be processed, is essential during the manufacturing process. Such a cleaning process requires a step of removing organic substances adhering to the substrate surface. In that case, for example, a wet process in which ozone water or the like is brought into contact with the substrate for cleaning and a dry process in which organic substances are decomposed and removed by emitting ultraviolet rays (UV) can be selected.
[0003]
[Problems to be solved by the invention]
However, when the substrate is wet cleaned with ozone water or the like, a long reaction time is required for the organic matter adhering to the substrate surface to be sufficiently decomposed, and depending on the steps performed after this cleaning process, In addition to the processing time of the cleaning process, the processing time of the drying process is necessary, and in order to improve production efficiency, there has been a demand for shortening these processing times.
[0004]
In addition, when dry cleaning with ultraviolet rays is performed, the processing time required for the cleaning process can be shortened, but there are the following problems.
(1) In the dry cleaning using ultraviolet rays, the distance between the ultraviolet light source and the substrate surface is set to about 1 mm to 1.5 mm.
However, for example, when processing a substrate of several hundred mm square, there is a possibility that deformation such as warpage or undulation will occur in a substrate made of glass or the like. Further, the deformation of the substrate such as warpage and undulation is expected to be about 2 mm to 3 mm when the size of the substrate is increased to about 1000 mm square.
For this reason, if the distance between the ultraviolet light source and the substrate surface is about 1 mm to 1.5 mm, the substrate may come into contact with the ultraviolet light source. It is necessary to set the interval sufficiently larger than the above-mentioned 1 mm to 1.5 mm. As a result, there is a possibility that the ultraviolet intensity on the substrate surface is lowered and a sufficient decomposition and cleaning effect cannot be obtained. Therefore, there is a problem that a sufficient cleaning effect may not be obtained with a short processing time.
[0005]
(2) As a cause of the decrease in the intensity of ultraviolet rays, it is considered that the ratio of ultraviolet rays absorbed by oxygen in the atmosphere between the ultraviolet light source and the substrate is large. It is conceivable that a vacuum chamber or the like is installed in the apparatus and the surroundings of the substrate are maintained in a vacuum atmosphere or the like to irradiate with ultraviolet rays to prevent a decrease in the ultraviolet intensity. In addition, there is a problem that utility facilities for controlling the atmosphere in a vacuum chamber or the like become large-scale.
(3) Further, as the size of the substrate to be processed increases, it is expected that the deformation of the above-mentioned substrate, such as warpage and undulation, will increase further. For this reason, the distance between the ultraviolet light source and the substrate surface is increased. There is a possibility of further expansion, and in this case as well, it is required to obtain a sufficient cleaning effect.
[0006]
The present invention has been made in view of the above circumstances, and intends to achieve the following object.
(1) To shorten the UV processing time for a substrate or other object to be processed.
(2) Thoroughly decompose and remove organic substances adhering to the substrate.
(3) To shorten the time for decomposing and removing organic substances adhering to the substrate.
(4) To provide a cleaning device capable of decomposing and removing organic substances and performing integrated processing such as cleaning and drying.
(5) To provide a cleaning device that can decompose and remove organic substances and perform integrated processing such as cleaning and drying, with a simple structure and low manufacturing costs.
[0007]
[Means for Solving the Problems]
  Of the present inventionIn the cleaning device, the part to be cleaned of the object to be cleaned at atmospheric pressureNeighborhoodA cleaning gas supply means for setting the oxygen partial pressure in the range of 20 Pa to 15 kPa, and an ultraviolet light source for irradiating the portion to be cleaned with ultraviolet rays.The cleaning gas supply means mixes an inert gas and air to adjust the cleaning gas in which the oxygen partial pressure is set in a range of 20 Pa to 15 kPa, and the mixing gas supplied from the mixing unit And a nozzle portion for ejecting a cleaning gas to the portion to be cleaned.,The ultraviolet light source generates active oxygen in the cleaning gas supplied from the cleaning gas supply means and in the vicinity of the portion to be cleaned by the ultraviolet light irradiated from the light source.This solves the above problem.
  The cleaning gas supply means sets an oxygen partial pressure in the vicinity of the site to be cleaned in a range of 20 Pa to 2 kPa, and the mixing unit mixes an inert gas and air to reduce the oxygen partial pressure. It is preferable to adjust the cleaning gas in the range of 20 Pa to 2 kPa.
  In the cleaning apparatus of the present invention,The ultraviolet light source is disposed in a sealing portion filled with an inert gas, and the vicinity of the site to be cleaned and the light source between which the oxygen partial pressure is set in the range by the cleaning gas supply means The sealing part is preferably present.
  In the present invention, the cleaning gas supply means may include an inert gas supply unit that ejects an inert gas in the vicinity of the site to be cleaned.
  In the present invention, the ultraviolet light source may be a xenon excimer light source.
  In the cleaning apparatus of the present invention, a suction removal means for sucking and removing the cleaning processing gas that has cleaned the target site from the vicinity of the target site can be provided.
  In the cleaning apparatus of the present invention, the ultraviolet light source is 2.0 mW / cm.²It is preferable that the distance between the portion to be cleaned and the ultraviolet light source is set in a range of 1 mm to 10 mm.
  Furthermore, the cleaning apparatus of the present invention can have distance adjusting means for adjusting the distance between the portion to be cleaned and the ultraviolet light source.
[0008]
In the UV treatment method of the present invention, the treatment site of the workpiece is a treatment gas atmosphere in which the partial pressure of oxygen is set in the range of 20 Pa to 15 kPa at atmospheric pressure, and the treatment site is irradiated with ultraviolet rays. Thus, it is possible to reduce the influence of oxygen absorption or the like by oxygen, and to maintain a sufficient ultraviolet intensity at the site to be processed in the atmospheric pressure.
[0009]
Here, decomposition of organic substances and the like by ultraviolet irradiation will be described.
In dry cleaning with ultraviolet light, for example, two wavelengths ν irradiated from an ultraviolet light source or the like are used.₁ , Ν₂ Decomposition is carried out by the following process with ultraviolet rays having:
For example, a wavelength ν of about 185 nm₁ UV light having oxygen in the air₂ Absorbed by ozone O_Three Is generated. This ozone O_Three For example, a wavelength ν of about 254 nm₂ Are absorbed, excited oxygen atoms (shown as O (1D) in formula (1); active oxygen, oxygen radical) are generated.
[Chemical 1]

[0010]
On the other hand, for example, a wavelength ν of about 185 nm₁ UV light having a strong photon energy is considered to break a molecular bond of an organic substance existing in the site to be treated._{m '}H_{n '}O_{k '}The cleaved molecule shown in FIG. 5 reacts with the excited oxygen atom having the above strong oxidizing power to produce CO, CO₂ , H₂It becomes gaseous like O 2 and can be scattered and removed.
[Chemical 2]

[0011]
By setting the oxygen concentration as above,
a) Attenuation of ultraviolet rays due to absorption or the like is reduced before reaching the vicinity of the site to be treated.
b) In the vicinity of the site to be treated, active oxygen that sufficiently reacts with the organic matter and can be removed is generated.
c) When arriving at the site to be treated, ensure sufficient UV illumination and energy to break organic molecular bonds.
The condition can be satisfied.
[0012]
In the UV treatment method of the present invention, the peak wavelength of the ultraviolet ray is set to around 172 nm, and the illuminance of the ultraviolet ray on the surface of the treatment site is 2.0 mW / cm.² It is desirable to set it as described above, thereby maintaining the intensity state such as ultraviolet energy and illuminance necessary for the processing of organic matter decomposition and the like, and capable of sufficiently shortening the processing time, at the portion to be processed. It becomes possible.
[0013]
Further, in the cleaning method of the present invention, a cleaning gas whose oxygen partial pressure is set in a range of 20 Pa to 15 kPa by an inert gas is supplied to a portion to be cleaned, and the portion to be cleaned is irradiated with ultraviolet rays. Therefore, it is possible to prevent attenuation of ultraviolet rays irradiated with oxygen or the like at atmospheric pressure, so that dirt such as organic matter is decomposed and cleaned in a portion to be processed (a portion to be cleaned) of the object to be processed (a portion to be cleaned). It is possible to maintain the ultraviolet intensity at a level where the cleaning process has a sufficient effect within a predetermined time. Here, as described later, the sufficient degree of the cleaning effect can be performed, for example, by measuring the contact angle with water at the site to be cleaned in organic cleaning.
[0014]
In the cleaning method of the present invention, the inert gas is prevented from being attenuated by adopting means in which the inert gas is a rare gas such as nitrogen gas, He, Ne, Ar, or Xe, preferably nitrogen gas. Furthermore, since this can be performed at a low cost, it is possible to maintain a sufficient ultraviolet illuminance at the site to be processed in the atmospheric pressure in the cleaning process.
[0015]
In the cleaning method of the present invention, the peak wavelength of the ultraviolet ray is less than 254 nm, more preferably, the peak wavelength of the ultraviolet ray is around 172 nm, so that the treatment of the organic matter decomposition or the like is performed at the site to be treated. In addition, it is possible to maintain the intensity state such as the energy and illuminance of ultraviolet rays that are necessary for the above-mentioned and can sufficiently shorten the processing time. Here, when the peak wavelength of the ultraviolet ray is 254 nm or more, energy necessary for the cleaning process cannot be obtained, and the organic matter and the like can be sufficiently decomposed and cleaned at the site to be cleaned. It is not preferable.
[0016]
Furthermore, in the cleaning method of the present invention, the illuminance of ultraviolet rays on the surface of the site to be cleaned is 2.0 mW / cm.² By setting as described above, a cleaning process for decomposing and cleaning organic matter and the like can exhibit a sufficient effect within a predetermined time. The illuminance of ultraviolet rays on the surface to be cleaned is 2.0 mW / cm² When set to the following, a sufficient cleaning effect cannot be obtained at the site to be cleaned, which is not preferable.
[0017]
In the cleaning method of the present invention, after cleaning the site to be cleaned, the cleaning treatment gas that has cleaned the site to be cleaned is removed from the site to be cleaned by sucking and removing ozone generated by ultraviolet irradiation, and decomposed organic matter It is possible to suck gas generated from the gas etc. and prevent them from diffusing. Further, by supplying the cleaning gas and sucking the cleaning processing gas, it is possible to more easily control the gas atmosphere such as the oxygen concentration in the site to be cleaned.
[0018]
In the cleaning apparatus of the present invention, the cleaning gas supply means for setting the oxygen partial pressure in the vicinity of the portion to be cleaned of the object to be cleaned in the range of 20 Pa to 15 kPa in the atmospheric pressure, and the ultraviolet ray for irradiating the portion to be cleaned with ultraviolet rays A cleaning gas supply means for supplying a cleaning gas to a portion to be cleaned and a partial pressure of oxygen in the vicinity of the portion to be cleaned being set in the above range, with an ultraviolet light source. By irradiating the portion to be cleaned with ultraviolet rays, the organic matter dirt, organic particles and the like of the portion to be cleaned are decomposed and cleaned. At this time, it is possible to reduce the influence of ultraviolet absorption or the like by oxygen at sites other than the site to be processed, and to perform sufficient cleaning processing at the site to be processed in a short time.
[0019]
In the present invention, the cleaning gas supply means includes an inert gas supply unit that ejects an inert gas in the vicinity of the portion to be cleaned, and an inert gas such as nitrogen gas or a rare gas is used as the cleaning gas in the portion to be cleaned. The oxygen concentration in the vicinity of the site to be cleaned can be set in the above range by directly ejecting to the vicinity. Thereby, the oxygen concentration range can be set only by an inert gas supply means such as nitrogen gas,
a) Attenuation of ultraviolet rays due to absorption or the like is reduced before reaching the vicinity of the site to be cleaned.
b) In the vicinity of the site to be cleaned, sufficient active oxygen is generated that reacts with the organic matter and can be scattered and removed.
c) Ensuring sufficient ultraviolet illuminance and energy to break the molecular bonds of organic matter when reaching the site to be cleaned.
It is possible to satisfy the condition.
[0020]
In the present invention, the ultraviolet light source is a xenon excimer light source, so that it is possible to use ultraviolet light having a high cleaning effect and a peak wavelength of 172 nm for the cleaning process.
[0021]
In the cleaning apparatus of the present invention, ozone generated by ultraviolet irradiation, decomposed organic matter, etc. are provided by providing suction removal means for sucking and removing the cleaning treatment gas that cleaned the cleaned part from the vicinity of the cleaned part. It is possible to suck the gas generated from the gas and prevent it from diffusing. Further, by supplying the cleaning gas and sucking the cleaning processing gas, it is possible to more easily control the gas atmosphere such as the oxygen concentration in the site to be cleaned.
[0022]
In the cleaning apparatus of the present invention, the ultraviolet light source is 2.0 mW / cm.² By having the above output and setting the distance between the site to be cleaned and the ultraviolet light source in the range of 1 mm to 10 mm, it is possible to maintain the ultraviolet intensity sufficient to obtain the above cleaning effect. In addition, it is possible to prevent an object to be cleaned such as a substrate from coming into contact with the ultraviolet light source or the like. When the distance between the site to be processed and the ultraviolet light source is 1 mm to 3 mm, it has a function of correcting warpage and undulation of the object to be cleaned.
[0023]
Furthermore, in the cleaning apparatus of the present invention, it is possible to more easily control the gas atmosphere such as the oxygen concentration in the site to be cleaned by having a distance adjusting means for adjusting the distance between the site to be cleaned and the ultraviolet light source. In addition, it is possible to more easily prevent an object to be cleaned such as a substrate from coming into contact with the ultraviolet light source or the like.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
[First Embodiment]
Hereinafter, a UV processing method, a cleaning method, and a cleaning apparatus according to a first embodiment of the present invention will be described with reference to the drawings.
1 is a perspective view showing a cleaning apparatus according to the present embodiment, FIG. 2 is a cross-sectional view taken along the line II-II in FIG. 1, and FIG. 3 is a plan view of the cleaning apparatus in FIG. It is. The cleaning apparatus of the present embodiment is used when cleaning the surface of a rectangular glass substrate (object to be cleaned), for example.
1 to 3, reference numeral 1 denotes a cleaning device (ultraviolet cleaning nozzle).
[0025]
As shown in FIGS. 1 to 3, the ultraviolet cleaning nozzle 1 of the present embodiment has an elongated box-shaped cleaning gas supply nozzle 2, a cleaning processing gas discharge nozzle 3, and an ultraviolet irradiation unit 4. The ultraviolet irradiation unit 4 is arranged adjacent to each other in the direction along the substrate surface in a state where the cleaning gas supply nozzle 2 and the cleaning processing gas discharge nozzle 3 are sandwiched. The cleaning gas supply nozzle 2 has a large number of through holes for ejecting a cleaning gas toward the surface of the substrate (object to be cleaned), and the ultraviolet irradiation unit 4 irradiates the portion to be cleaned of the substrate with ultraviolet rays. The cleaning gas discharge nozzle 3 has a function and has a large number of through holes for discharging the cleaning gas generated from the substrate surface by ultraviolet irradiation from the substrate surface.
[0026]
In the cleaning gas supply nozzle 2, as shown in FIG. 2, a porous material 22 having a large number of through holes is accommodated and fixed inside a box-shaped casing 21. The porous material 22 is accommodated and fixed so as to cover one surface of the casing 21 facing the substrate K when in use, and the cleaning gas is stably ejected uniformly into the surface of the porous material 21 inside the casing 21. In order to achieve this, a space portion 24 serving as a so-called animal pressure device is provided, and the cleaning gas supply port 23 communicates with the space portion 24.
For example, a metal, ceramic, or the like is used for the porous material 22, and it is desirable that the surface of the porous material 22 facing the substrate K has a small surface roughness and a small undulation. The casing 21 is provided with a cleaning gas supply port 23, and the cleaning gas supply port 5 is connected to the cleaning gas supply port 23. The cleaning gas supply nozzle 2 ejects the cleaning gas supplied from the cleaning gas supply unit 5 through a large number of through holes of the porous material 22 via the space 24 (the flow of the cleaning gas is shown by a solid line in FIG. 2). The oxygen partial pressure in the vicinity of the site to be cleaned of the substrate K at atmospheric pressure is set to a range of 20 Pa to 15 kPa.
[0027]
The cleaning gas supply unit 5 mixes an inert gas and air to form a cleaning gas, and supplies the cleaning gas to the cleaning gas supply nozzle 2. When the cleaning gas is ejected to the substrate K, the cleaning gas is supplied to the cleaning gas supply nozzle 2. A control unit for controlling the mixing of the inert gas and the air is also included so that the oxygen partial pressure is set in the range of 20 Pa to 15 kPa in the atmospheric pressure.
Here, as the inert gas, a gas that is transparent to ultraviolet rays, such as nitrogen gas, rare gases such as He, Ne, Ar, and Xe, that is, a gas that is transparent to ultraviolet rays, is adopted. From the aspect, nitrogen gas is preferable.
The cleaning gas supply nozzle 2 and the cleaning gas supply unit 5 constitute cleaning gas supply means.
[0028]
The ultraviolet irradiation unit 4 has an ultraviolet light source 42 extending along the longitudinal direction of the casing 41 in a sealing portion 44 inside the box-shaped casing 41. In the casing 41, one surface of the casing 41 facing the substrate K in use is sealed with quartz glass 43 in a state in which nitrogen gas is filled around the ultraviolet light source 41 of the sealing portion 44.
The ultraviolet light source 42 has a peak wavelength of irradiated ultraviolet light of 254 nm or less, for example, Xe₂ Xenon excimer light source (dielectric barrier discharge excimer lamp) which is sealed by a light emitting tube made of a dielectric material such as quartz glass and emits discharge plasma s when it is supplied with high frequency power from a metal electrode. ) And ultraviolet rays having a peak wavelength of 172 nm from the xenon dimer are irradiated.
FIG. 4 is a spectral distribution diagram of ultraviolet rays emitted from the ultraviolet light source 42.
Here, the ultraviolet light emitted from the ultraviolet light source 42 has a peak wavelength ν as shown in FIG._Three Is 172 nm and its half width is 14 nm. Furthermore, the ultraviolet light source 42 is 2.0 mW / cm.² While having the above output, the emission length of the ultraviolet light source 42 is L as shown in FIG.₁ Set to
[0029]
Here, when the peak wavelength of the ultraviolet ray is 254 nm or more, the photon energy necessary for the cleaning process cannot be obtained, and the generation of excited oxygen atoms and the generation of organic matter are performed in the cleaned portion of the substrate K as described later. It is not preferable because the molecular bond cannot be sufficiently cut and the organic substance may not be sufficiently decomposed and washed.
In addition, the length L of the light emission source₁ Is set to about 1 to 1.5 times corresponding to the width dimension of the substrate K whose maximum dimension is set to about 960 mm to 1500 mm.
The length L of the light source₁ Is set to be smaller than the width of the substrate K, the process cannot be completed by a single scan, and the process needs to be repeated a plurality of times. In this case, each process is performed uniformly. This may not be desirable. Also, the length L of the light source₁ Is set to be larger than 1500 mm, it may be larger than the width dimension of the substrate K, and there is a possibility that a portion that emits light without being irradiated to the substrate K is generated. In this case, the power consumption of the ultraviolet light source 42 is the emission length. Therefore, the running cost increases, which is not preferable. It is preferable to select a light source that is at least as long as or slightly longer than the width of the substrate K.
[0030]
As shown in FIG. 2, the cleaning gas discharge nozzle 3 has a structure substantially equivalent to the cleaning gas supply nozzle 2, and has a space 34 inside the box-shaped casing 31 and a large number of through holes. The porous material 32 is accommodated and fixed. The casing 31 is provided with a cleaning processing gas discharge port 33, and the cleaning processing gas discharge port 6 is connected to the cleaning processing gas discharge port 33.
[0031]
The cleaning process gas discharge unit 6 discharges a cleaning process gas composed of ozone generated by ultraviolet irradiation near the cleaned part of the substrate K and gas generated from decomposed organic substances, etc. during use. The cleaning material gas is sucked and removed through a large number of through holes of the porous material 32 of the nozzle 3 through the cleaning gas discharge port 33 (the flow of the cleaning gas and the like is indicated by solid arrows in FIG. 2), and this cleaning process is performed. It also has a control unit that controls the control of the oxygen partial pressure in the vicinity of the site to be cleaned of the substrate K by removing the gas by suction.
The cleaning process gas discharge nozzle 3 and the cleaning process gas discharge unit 6 constitute suction removal means.
[0032]
As shown in FIG. 2, the ultraviolet cleaning nozzle 1 includes a cleaning gas supply nozzle 2, a cleaning processing gas discharge nozzle 3, and an ultraviolet irradiation unit 4 so that the surface on the side facing the substrate K is flush when in use. Is fixed.
Here, the cleaning gas supply nozzle 2, the cleaning processing gas discharge nozzle 3, and the ultraviolet irradiation unit 4 are fixed to each other by fixing parts such as screws.
[0033]
At this time, as shown in FIG. 2, a distance L between the portion to be cleaned of the substrate K and the ultraviolet light source 42 in the use state._Three Is set in the range of 1 mm to 10 mm, and the illuminance of ultraviolet rays at the site to be cleaned is 2.0 mW / cm² The distance L between the ultraviolet cleaning nozzle 1 and the substrate K is set as described above.₂ The substrate K and the UV cleaning nozzle 1 do not come into contact with each other in response to deformations such as warpage and swell of the substrate K that are considered corresponding to the size of the substrate K set to a maximum size of about 960 mm to 1500 mm. Is set as follows.
Here, a distance L between the portion to be cleaned of the substrate K and the ultraviolet light source 42 in a use state._Three However, when it is set to 1 mm or less, there is a possibility that the substrate K and the ultraviolet cleaning nozzle 1 come into contact with each other, which is not preferable. In addition, the distance L between the portion to be cleaned of the substrate K and the ultraviolet light source 42 in the use state_Three However, when the thickness is set to 10 mm or more, the ultraviolet intensity at the portion to be cleaned of the substrate K is lowered, and there is a possibility that the ultraviolet illuminance necessary for the decomposition cleaning cannot be maintained.
Similarly, the illuminance of ultraviolet rays at the site to be cleaned is 2.0 mW / cm.² When set to the following, the ultraviolet illuminance is insufficient, and there is a possibility that sufficient decomposition and cleaning treatment cannot be performed, which is not preferable.
[0034]
In the ultraviolet cleaning nozzle 1 having the above-described configuration, the cleaning gas supply nozzle 2, the cleaning processing gas discharge nozzle 3, and the ultraviolet irradiation unit 4 are arranged adjacent to each other in the direction along the surface of the substrate K. The ultraviolet cleaning nozzle 1 and the substrate in the direction in which the supply nozzle 2, the ultraviolet irradiation unit 4, and the cleaning gas discharge nozzle 3 are opposed in this order (in FIG. 2, the nozzle 1 moves from right to left and the substrate K moves from left to right). The substrate K is subjected to a cleaning process (UV process) by relatively moving K.
Here, in the ultraviolet cleaning nozzle 1, when the ultraviolet cleaning nozzle 1 and the substrate K are relatively moved, the distance L between the portion to be cleaned of the substrate K and the ultraviolet light source 42._Three However, a distance adjusting means having a control unit that adjusts the relative position between the ultraviolet cleaning nozzle 1 and the substrate K is provided so that it is maintained in the range of 1 mm to 10 mm.
[0035]
In such a cleaning method using the ultraviolet cleaning nozzle 1, first, the distance L is placed above the surface of the substrate K.₂ When the cleaning gas supply nozzle 2 arranged at a distance is passed, the oxygen partial pressure in the atmospheric pressure is set in the range of 20 Pa to 15 kPa in the vicinity of the portion to be cleaned on the surface of the substrate K by the jetting cleaning gas. Next, ultraviolet light having a peak wavelength of about 172 nm is irradiated from the ultraviolet light source 42 of the ultraviolet irradiation unit 4 toward the portion to be cleaned on the surface of the substrate K in which the oxygen partial pressure is in this range, so that the surface of the substrate K is covered. Organic substances that adhere to or contaminate the cleaning site are decomposed. Then, cleaning gas containing ozone generated by ultraviolet irradiation and gas generated from decomposed organic matter is sucked from the surface of the substrate K through the many through holes of the porous material 32 of the cleaning gas discharge nozzle 3. Discharged. In this way, the entire surface of the substrate K can be cleaned by moving the ultraviolet cleaning nozzle 1 and the substrate relative to the entire substrate K.
[0036]
Here, decomposition of organic substances and the like by ultraviolet irradiation will be described.
In the cleaning process using ultraviolet light, for example, the ultraviolet light emitted from the ultraviolet light source 42 has a peak wavelength ν._Three Is 172 nm and its half-value width is 14 nm. This wavelength ν_Three Decomposition is carried out by the following process by ultraviolet rays having Wavelength ν of about 172 nm_Three UV light having a wavelength shorter than 175 nm, which is directly absorbed by oxygen in the atmosphere, generates excited oxygen atoms (shown as O (1D) in formula (3); active oxygen, oxygen radical) To do.
[Chemical 3]

[0037]
Wavelength ν assumed to be 172 nm_Three UV light having a wavelength ν of 185 nm and 254 nm as described above₁ , Ν₂ In the same way as ultraviolet rays having oxygen O2 in the air₂ Absorbed by ozone O_Three In addition, this ozone O_Three There is also a path for generating excited oxygen atoms (shown as O (1D) in the formula (4)) from.
[Formula 4]

[0038]
This wavelength ν of 172 nm_Three UV light having a wavelength ν of around 185 nm and 254 nm described above₁ , Ν₂ It is considered that the photon energy is stronger than that of ultraviolet rays having a molecular weight, and the molecular bonds of organic substances existing at the site to be treated are more easily broken._{m '}H_{n '}O_{k '}As shown by the above, the cleaved molecule reacts with the excited oxygen atom having the above strong oxidizing power to produce CO, CO₂ , H₂It becomes gaseous like O 2 and can be scattered and removed.
[Chemical formula 5]

[0039]
Thus, the wavelengths ν, which are 185 nm and 254 nm, as described above.₁ , Ν₂ The wavelength ν of 172 nm from the xenon excimer light source compared to the ultraviolet light having_Three UV light having a large number of excited oxygen atoms can be generated and the molecular bonds of organic substances can be broken more easily, so that the cleaning speed can be increased and the processing time can be shortened. Become.
[0040]
In the cleaning process by the ultraviolet cleaning nozzle 1 of the present embodiment, cleaning gas is ejected from the cleaning gas supply nozzle 2, the vicinity of the portion to be cleaned of the substrate K is at atmospheric pressure, and the oxygen partial pressure is in the range of 20 Pa to 15 kPa. By setting the cleaning gas atmosphere to be set, the oxygen partial pressure is controlled by a transparent inert gas with respect to the ultraviolet rays irradiated from the ultraviolet light source 42, so that excessive absorption of the ultraviolet rays can be prevented. At the same time, by controlling the oxygen partial pressure, it is possible to generate as many excited oxygen atoms that are generated by ultraviolet irradiation and react with organic substances whose molecular bonds are broken as much as necessary for decomposition cleaning.
Therefore,
a) Attenuation of ultraviolet rays due to absorption or the like is reduced before reaching the vicinity of the site to be cleaned.
b) In the vicinity of the site to be cleaned, sufficiently generate excited oxygen atoms that can be scattered and removed by reacting with organic substances.
c) When reaching the site to be cleaned, ensure sufficient UV illuminance to break the molecular bonds of the organic matter.
It is possible to satisfy the condition.
Further, such control of the oxygen partial pressure can be performed at atmospheric pressure by the control unit of the cleaning gas supply means and the suction removal means, and it is not necessary to provide a vacuum chamber or the like, and can be provided at low cost. It becomes possible.
[0041]
In the present embodiment, since the peak wavelength of the ultraviolet ray is set to around 172 nm, the processed portion of the substrate K has photon energy necessary for breaking the molecular bond of the organic substance and generating sufficient excited oxygen atoms. The processing time can be sufficiently shortened.
Moreover, in this embodiment, the illumination intensity of the ultraviolet-ray in the said to-be-processed site | part surface is 2.0 mW / cm.² By setting as described above, the illuminance necessary for breaking the molecular bond of the organic substance and generating sufficient excited oxygen atoms is obtained, so that the processing time can be sufficiently shortened.
In the present embodiment, since the ultraviolet light source 42 is a xenon excimer light source, the peak wavelength of the ultraviolet light is set near 172 nm and the illuminance of ultraviolet light on the surface of the treatment site is inexpensive and simple. 2.0 mW / cm² It can set to the above and can improve a cleaning effect.
[0042]
In this embodiment, the ultraviolet light source 42 is 2.0 mW / cm.² The above-mentioned output is maintained, and the distance between the portion to be cleaned of the substrate K and the ultraviolet light source 42 is set in the range of 1 mm to 10 mm, thereby maintaining the ultraviolet intensity that sufficiently obtains the cleaning effect described later. In addition, the object to be cleaned on the substrate K can be prevented from coming into contact with the ultraviolet light source 42 and the ultraviolet cleaning nozzle 1.
[0043]
In the ultraviolet cleaning nozzle 1, when the ultraviolet cleaning nozzle 1 and the substrate K are relatively moved, the distance L between the portion to be cleaned of the substrate K and the ultraviolet light source 42._Three Has a distance adjusting means for adjusting the relative position between the ultraviolet cleaning nozzle 1 and the substrate K so that the cleaning gas atmosphere such as an oxygen partial pressure at the site to be cleaned can be controlled. It is possible to more easily prevent the object to be cleaned of the substrate K from coming into contact with the ultraviolet light source 42 and the ultraviolet cleaning nozzle 1.
[0044]
In this embodiment, after cleaning the site to be cleaned, the cleaning gas that cleaned the site to be cleaned is removed by suction from the site to be cleaned, so that the remaining cleaning gas, ozone generated by ultraviolet irradiation, and decomposition It is possible to suck gas generated from the generated organic matter and the like and prevent them from diffusing. Further, by supplying the cleaning gas and sucking the cleaning processing gas, it is possible to more easily control the gas atmosphere such as the oxygen concentration in the site to be cleaned.
be able to.
[0045]
Here, at the site to be processed (the site to be cleaned) of the substrate K, the cleaning process for decomposing and cleaning the organic contaminants is at a level that has a sufficient effect within a predetermined time. This can be done by measuring the contact angle with moisture in
[0046]
5 and 6 are graphs showing the relationship between the oxygen partial pressure in the vicinity of the site to be cleaned in the cleaning process and the contact angle of the surface of the substrate K after the cleaning process, and FIG. 7 is a schematic diagram for explaining the contact angle.
As shown in FIG. 7, the contact angle means an angle θ between the contact surface of the surface of the water droplet W on the substrate K and the surface of the substrate K. For example, the surface of the substrate K is contaminated with organic substances. In this case, the contact angle θ is increased due to the hydrophobicity of the organic substance, so that it is used as an indicator of the organic substance residual degree on the surface of the substrate K, that is, the cleaning state.
[0047]
As in the present embodiment, for example, when the cleaning time is 10 seconds and the oxygen partial pressure in the vicinity of the site to be cleaned of the substrate K is set in the range of 20 Pa to 15 kPa, Distance L with ultraviolet light source 42_Three The result of FIG. 5 in which is set to 1 mm, and the distance L_Three As a result of FIG. 6 in which is set to 5 mm, a sufficient cleaning effect can be obtained in any case. Here, obtaining a sufficient cleaning effect means that the contact angle θ is 10 degrees or less, preferably 5 degrees or less, for a predetermined cleaning processing time of 6 sec to 10 sec, for example.
[0048]
[Second Embodiment]
Hereinafter, a UV processing method, a cleaning method, and a cleaning device according to a second embodiment of the present invention will be described with reference to the drawings.
8 is a perspective view showing the cleaning device (ultraviolet cleaning nozzle) of the present embodiment, FIG. 9 is a cross-sectional view taken along the line IX-IX in FIG. 8, and FIG. 10 is a surface of the cleaning device in FIG. It is the top view seen from the side. Whereas the cleaning device (ultraviolet cleaning nozzle) of the first embodiment performs cleaning gas control only on the substrate surface side, the cleaning device (ultraviolet cleaning nozzle) of the present embodiment is a substrate. The cleaning gas can be controlled simultaneously from the back side.
[0049]
In the present embodiment, the parts different from the first embodiment shown in FIGS. 1 to 3 are the cleaning gas supply nozzle (lower) 7 and the cleaning processing gas discharge nozzle (lower) 8 at positions corresponding to the back side of the substrate K. The components substantially the same as those of the first embodiment shown in FIGS. 1 to 3 are denoted by the same reference numerals, and the description thereof is omitted.
[0050]
As shown in FIG. 9, the cleaning gas supply nozzle (lower) 7 accommodates and fixes a porous material 72 having a large number of through-holes inside a box-like casing 71 in the same manner as the cleaning gas supply nozzle 2. Has been. The porous material 72 is accommodated and fixed so as to cover one surface of the casing 71 facing the substrate K when in use, and the cleaning gas is stably ejected uniformly into the surface of the porous material 71 inside the casing 71. A space portion 74 is provided, and the cleaning gas supply port 73 communicates with the space portion 74.
For example, metal, plastic, ceramic, or the like is used for the porous material 72, and it is desirable that the surface of the porous material 72 facing the substrate K has a small surface roughness and a small undulation.
A cleaning gas supply port 73 is provided in the casing 71, and a cleaning gas supply unit 5 ′ is connected to the cleaning gas supply port 73. The cleaning gas supply nozzle (lower) 7 ejects the cleaning gas supplied from the cleaning gas supply unit 5 ′ through the numerous through holes of the porous material 72 via the space 74 (in FIG. 9, the cleaning gas). The cleaning gas supply means is configured to set the oxygen partial pressure in the vicinity of the portion to be cleaned of the substrate K at atmospheric pressure in the range of 20 Pa to 15 kPa.
The cleaning gas supply unit 5 ′ mixes an inert gas and air to form a cleaning gas, and supplies this cleaning gas to the cleaning gas supply nozzle (lower) 7. In FIG. 9, the cleaning gas supply unit 5 ′ is described as having a different configuration from the cleaning gas supply unit 5 connected to the cleaning gas supply nozzle 2. However, the same configuration may be used.
[0051]
As shown in FIG. 9, the cleaning gas discharge nozzle (lower) 8 has substantially the same structure as the cleaning gas supply nozzle (lower) 7, and has a space 84 inside a box-shaped casing 81. A porous material 82 having a large number of through holes is accommodated and fixed. The casing 81 is provided with a cleaning process gas discharge port 83, and a cleaning process gas discharge unit 6 ′ is connected to the cleaning process gas discharge port 83 and constitutes a suction removal means.
When used, the cleaning gas discharge unit 6 ′ sucks and removes the cleaning gas in the vicinity of the portion to be cleaned of the substrate K (the flow of the cleaning gas and the like is indicated by solid arrows in FIG. 9). . In FIG. 9, the cleaning process gas discharge unit 6 ′ is described as having a different configuration from the cleaning process gas discharge unit 6 connected to the cleaning process gas discharge nozzle 3, but the same configuration may be used.
[0052]
The cleaning gas supply nozzle (lower) 7 and the cleaning process gas discharge nozzle (lower) 8 are sandwiched between the cleaning gas supply nozzle 2, the cleaning process gas discharge nozzle 3 and the ultraviolet irradiation unit 4 in the use state. The porous materials 72 and 82 are arranged to face the porous materials 22 and 32 and the quartz glass 43 at positions facing each other. The cleaning gas supply nozzle (lower) 7 and the cleaning processing gas discharge nozzle (lower) 8 are fixed so that the porous materials 72 and 82 are flush with each other. As shown in FIG. The length L in the direction of movement of the substrate K between the nozzle (lower) 7 and the cleaning gas discharge nozzle (lower) 8_Five However, the length L of the cleaning gas supply nozzle 2, the cleaning gas discharge nozzle 3, and the ultraviolet irradiation unit 4 in the moving direction of the substrate K shown in FIG._Five Is set to be approximately equal to Here, the length dimensions of the cleaning gas supply nozzle (lower) 7 and the cleaning processing gas discharge nozzle (lower) 8 in the movement direction of the substrate K are the same as the cleaning gas supply nozzle 2, the cleaning processing gas discharge nozzle 3 shown in FIG. Length dimension L in the direction of movement of the substrate K with the ultraviolet irradiation unit 4_Five It is also possible to set a larger value.
[0053]
As shown in FIGS. 8 to 10, the ultraviolet cleaning nozzle 1 of the present embodiment includes a cleaning gas supply nozzle (lower) 7 and a cleaning processing gas discharge nozzle below the ultraviolet cleaning nozzle 1 of the first embodiment. (Bottom) 8 is arranged, and the nozzles 2, 3 and 4 positioned above the substrate K and the nozzles 7 and 8 positioned below the substrate K move independently as separate bodies. Alternatively, they may be connected by an arbitrary method and moved together.
Here, as in the first embodiment shown in FIGS. 1 to 3, the distance L between the cleaning gas supply nozzle (lower) 7 and the cleaning processing gas discharge nozzle (lower) 8 and the portion to be cleaned of the substrate K._Four A distance adjusting means for performing the above adjustment, that is, performing a relative position adjustment is provided.
[0054]
As a result, the substrate K is not positioned between the nozzles 2, 3, 4 and the nozzles 7, 8, that is, before performing the cleaning process, between the nozzles 2, 3, 4 and the nozzles 7, 8. The space can be set to the above-described cleaning gas atmosphere, and the oxygen partial pressure in the vicinity thereof can be set more easily. Therefore, the oxygen partial pressure in the vicinity of the portion to be cleaned of the substrate K can be set more easily, and the cleaning efficiency can be improved.
Further, it is possible to more easily control the distance setting between the substrate K and the nozzles 2, 3, 4 and the nozzles 7, 8.
Further, by providing the lower nozzles 7 and 8, it is possible to prevent the cleaning gas from diffusing and to discharge ozone or the like more easily.
[0055]
[Third Embodiment]
Hereinafter, a UV processing method, a cleaning method, and a cleaning apparatus according to a third embodiment of the present invention will be described with reference to the drawings.
This embodiment is an example of a cleaning apparatus provided with the drying nozzle of the present invention. FIG. 11 is a diagram showing a schematic configuration of the cleaning apparatus 51 according to the present embodiment, which is an apparatus for cleaning a single glass sheet of a large glass substrate (hereinafter simply referred to as a substrate) of about several hundred mm square, for example.
In the figure, reference numeral 52 denotes a cleaning unit, 53 a stage (substrate holding means), 1, 55, 56, 49 cleaning nozzles, 50 a drying nozzle, 57 a substrate transfer robot, 58 a loader cassette, and 59 an unloader cassette. , 60 is a hydrogen water / ozone water generation unit, 61 is a cleaning liquid regeneration unit, and K is a substrate.
[0056]
As shown in FIG. 11, the center of the upper surface of the apparatus is a cleaning unit 52, and a stage 53 that holds the substrate K is provided. The stage 53 is provided with a rectangular step portion that matches the shape of the substrate K, and the substrate K is fitted on the step portion, and the surface of the substrate K and the surface of the stage 53 are held on the stage 53 in a flush state. It has come to be. In addition, a space is formed below the step, and a substrate lifting shaft protrudes from below the stage 53 in the space. A shaft driving source such as a cylinder is provided at the lower end of the substrate elevating shaft, and the substrate elevating shaft is moved up and down by the operation of the cylinder when the substrate K is transferred by a substrate transfer robot 57 described later. Along with this, the substrate K is raised or lowered. A nozzle for cleaning the back surface of the substrate K protrudes from a hole provided in the center of the stage. In this apparatus, the front surface side is mainly cleaned, but at the same time, the back surface side can be lightly cleaned.
[0057]
A pair of rack bases 62 are provided at positions facing each other across the stage 53, and cleaning nozzles 1, 55, 56, 49 are installed between the rack bases 62. The cleaning nozzles are composed of four nozzles arranged in parallel, and the cleaning nozzles 1, 55, 56, and 49 perform cleaning by different cleaning methods. In the case of the present embodiment, these four nozzles supply the cleaning gas from the cleaning gas supply means (not shown) to the substrate K and irradiate the ultraviolet rays from the ultraviolet lamp 42 to mainly decompose and remove organic substances. Ultraviolet cleaning nozzle 1 according to the embodiment, ozone water ultrasonic cleaning nozzle 55 for cleaning by supplying ultrasonic vibration while supplying ozone water and ultrasonic element 63 while supplying ozone water, ultrasonic element 63 while supplying hydrogen water A hydrogen water ultrasonic cleaning nozzle 56 for cleaning by applying ultrasonic vibration, and a pure water rinsing cleaning nozzle 49 for supplying pure water to perform rinsing cleaning. By moving these four nozzles sequentially along the rack base 62 while maintaining a constant distance from the substrate K above the substrate K, the entire surface to be cleaned of the substrate K is cleaned by four types of cleaning methods. It has a configuration. Further, a drying nozzle 50 is installed between the same rack bases 62, and the wet substrate K after cleaning is dried by the drying nozzle 50.
In FIG. 11, the ultraviolet cleaning nozzle 1 is shown as a single rod, but in actuality, the configuration is the same as that in the first and second embodiments described above, and the cleaning gas supply nozzle 2 A cleaning gas discharge nozzle 3, an ultraviolet irradiation unit 4, and the like are included.
[0058]
As the moving means of each nozzle, sliders that can be moved horizontally along the linear guides on each rack base 62 are provided, and support columns are erected on the upper surface of each slider. 1, 55, 56, 49 and both ends of the drying nozzle 50 are fixed. A drive source such as a motor is installed on each slider, and each slider is configured to run on the rack base 62. Each of the cleaning nozzles 1, 55, 56, 49 and the drying nozzle 50 is individually moved horizontally by operating the motor on each slider in accordance with a control signal supplied from a control unit (not shown) of the apparatus. It is the composition to do. Further, a driving source such as a cylinder (not shown) is provided on the support column, and the height of each of the cleaning nozzles 1, 55, 56, 49 and the drying nozzle 50, that is, each cleaning nozzle is moved by the vertical movement of the support column. 1, 55, 56, 49 and the distance between the substrate K and the distance between the drying nozzle 50 and the substrate K can be adjusted. These constitute distance adjusting means.
[0059]
Each of the cleaning nozzles 55, 56, and 49 is formed with an introduction passage having an introduction port for introducing the cleaning liquid at one end and a discharge passage having a discharge port for discharging the washed cleaning liquid to the outside at one end. The introduction passage and the discharge passage intersect each other at the other end to form an intersection, and an opening that opens toward the substrate K is provided at the intersection. It is called (fluid-saving nozzle). In this case, the opening extends in a direction intersecting with the parallel direction of the cleaning nozzles 55, 56, and 49 at least as long as the width of the substrate K (in the case of the present embodiment, one cleaning nozzle). 3), there are provided three sets of intersections and openings where the introduction passage and the discharge passage intersect, and the combination of the three extensions extends the length of the substrate K or more. Using a pressure reduction pump in the pressure control part on the discharge passage side, and controlling the force of sucking the cleaning liquid at the intersection with this pressure reduction pump, the pressure of the cleaning liquid in contact with the atmosphere in the opening (the surface tension of the cleaning liquid and the substrate) (Including the surface tension of the surface to be cleaned of W) and the atmospheric pressure. That is, the pressure P of the cleaning liquid in contact with the atmosphere of the opening_w(Including the surface tension of the cleaning liquid and the surface tension of the surface to be cleaned of the substrate K) and the atmospheric pressure P_aRelationship with P_w≒ P_aThus, the cleaning liquid supplied to the substrate K through the opening and contacting the substrate K is discharged to the discharge passage without leaking outside the cleaning nozzle. That is, the cleaning liquid supplied onto the substrate K from the cleaning nozzle is removed from the substrate K without contacting any part other than the part (opening) where the cleaning liquid is supplied on the substrate K. Further, an ultrasonic element 63 is provided above the intersection so as to face the substrate K, and ultrasonic waves are applied to the cleaning liquid while the substrate K is being cleaned.
[0060]
A hydrogen water / ozone water generation unit 60 and a cleaning liquid regeneration unit 61 are provided on the side of the cleaning unit 52. A hydrogen water production device 64 and an ozone water production device 65 are incorporated in the hydrogen water / ozone water generation unit 60. Any cleaning liquid can be produced by dissolving hydrogen gas or ozone gas in pure water. Then, the hydrogen water generated by the hydrogen water production apparatus 64 is supplied to the hydrogen water ultrasonic cleaning nozzle 56 by a liquid feed pump 67 provided in the middle of the hydrogen water supply pipe 66. Similarly, the ozone water generated by the ozone water production apparatus 65 is supplied to the ozone water ultrasonic cleaning nozzle 55 by a liquid feed pump 69 provided in the middle of the ozone water supply pipe 68. The pure water rinse cleaning nozzle 49 is supplied with pure water from a pure water supply pipe (not shown) in the production line.
[0061]
Further, the cleaning liquid regenerating unit 61 is provided with filters 70 and 171 for removing particles and foreign substances contained in the used cleaning liquid. A hydrogen water filter 70 for removing particles in the hydrogen water and an ozone water filter 171 for removing particles in the ozone water are provided in separate systems. That is, the used hydrogen water discharged from the discharge port of the hydrogen water ultrasonic cleaning nozzle 56 is recovered by the hydrogen water filter 70 by the liquid feed pump 173 provided in the middle of the hydrogen water recovery pipe 172. It has become. Similarly, the used ozone water discharged from the discharge port of the ozone water ultrasonic cleaning nozzle 55 is recovered by the ozone water filter 171 by the liquid feed pump 75 provided in the middle of the ozone water recovery pipe 174. It is like that.
[0062]
The hydrogen water after passing through the hydrogen water filter 70 is supplied to the hydrogen water ultrasonic cleaning nozzle 56 by a liquid feed pump 77 provided in the middle of the regenerated hydrogen water supply pipe 76. . Similarly, the ozone water that has passed through the ozone water filter 171 is supplied to the ozone water ultrasonic cleaning nozzle 55 by a liquid feed pump 79 provided in the middle of the regenerated ozone water supply pipe 78. Yes. The hydrogen water supply pipe 66 and the regenerated hydrogen water supply pipe 76 are connected in front of the hydrogen water ultrasonic cleaning nozzle 56, and new hydrogen water is introduced into the hydrogen water ultrasonic cleaning nozzle 56 by the valve 80 or regenerated. It is possible to switch between introducing hydrogen water. Similarly, the ozone water supply pipe 68 and the regenerated ozone water supply pipe 78 are connected in front of the ozone water ultrasonic cleaning nozzle 55, and new ozone water is introduced into the ozone water ultrasonic cleaning nozzle 55 by the valve 181. It is possible to switch between introducing regenerated ozone water. In addition, although the hydrogen water and ozone water after passing each filter 70,171 have the particle removed, since the liquid gas content concentration has fallen, the hydrogen water production apparatus 64 and ozone again through piping. You may make it return to the water manufacturing apparatus 65 and replenish hydrogen gas and ozone gas.
[0063]
A loader cassette 58 and an unloader cassette 59 are detachably provided on the side of the cleaning unit 52. These two cassettes 58 and 59 are of the same shape that can accommodate a plurality of substrates K, the substrate K before cleaning is stored in the loader cassette 58, and the cleaned substrate K is stored in the unloader cassette 59. Be contained. A substrate transfer robot 57 is installed at an intermediate position between the cleaning unit 52, the loader cassette 58, and the unloader cassette 59. The substrate transport robot 57 has an arm 182 having an expandable / contractible link mechanism at an upper portion thereof. The arm 182 is rotatable and can be moved up and down, and the substrate K is supported and transported by a tip portion of the arm 182. ing.
[0064]
The cleaning device 51 having the above configuration includes, for example, the distance between the cleaning nozzles 1, 55, 56, 49 or the drying nozzle 50 and the substrate K, the moving speed of the cleaning nozzle or the drying nozzle, the flow rate of the cleaning gas, and the oxygen partial pressure. The operation of each unit is controlled by the control unit except that the operator sets various cleaning conditions and drying conditions such as the flow rate of the cleaning liquid, and the system is configured to automatically operate. Therefore, when using this cleaning apparatus 51, the substrate K before cleaning is set in the loader cassette 58, and if the operator operates the start switch, the substrate transfer robot 57 moves the substrate K from the loader cassette 58 onto the stage 53. UV cleaning, ozone water ultrasonic cleaning, hydrogen water ultrasonic cleaning, rinsing cleaning, and drying are sequentially and automatically performed on the stage 53 by the cleaning nozzles 1, 55, 56, 49 and the drying nozzle 50 on the stage 53. After drying, the substrate is transferred to the unloader cassette 59 by the substrate transfer robot 57.
[0065]
In the cleaning apparatus 51 of the present embodiment, each of the four cleaning nozzles 1, 55, 56, 49 is subjected to different cleaning methods such as ultraviolet cleaning, ozone water ultrasonic cleaning, hydrogen water ultrasonic cleaning, and rinse cleaning. Since the cleaning process is performed, various cleaning methods can be performed with one apparatus. Therefore, for example, organic substances etc. are removed and cleaned by irradiating with ultraviolet rays, particles of fine particle size are removed by ultrasonic cleaning with hydrogen water and ultrasonic cleaning with ozone water, and the cleaning liquid adhering to the substrate surface is further washed away by rinsing. Thus, various objects to be removed can be sufficiently cleaned and removed, such as performing final cleaning. Further, in the case of the cleaning apparatus of the present embodiment, since the drying nozzle 50 is provided, it is possible to automatically perform integrated processing of cleaning and drying. In particular, in the cleaning process by the ultraviolet cleaning nozzle 1 of the above-described embodiment, the cleaning time can be set short by setting the oxygen partial pressure, and further, for organic substance decomposition processing using conventional ozone water. Since there is no need to bring moisture into contact with the surface of the substrate K unlike a nozzle, there is no need to dry the substrate K. And according to the cleaning apparatus 51 of the present embodiment, the provision of the ultraviolet cleaning nozzle 1 of the above-described embodiment makes it suitable for production lines of various electronic devices such as semiconductor devices and liquid crystal display panels. A highly efficient cleaning device can be realized.
[0066]
The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, air and an inert gas are mixed as a cleaning gas and then supplied to the cleaning gas supply nozzle 2 or the like. For example, only an inert gas, which is a nitrogen gas, is jetted near the portion to be cleaned of the substrate K. It is also possible to provide an inert gas supply unit that controls the oxygen partial pressure in the vicinity of the site to be cleaned by mixing the inert gas with air existing in the vicinity of the site to be cleaned of the substrate K. In addition, by this inert gas supply unit, only the inert gas is jetted near the site to be cleaned, and at the same time, the oxygen partial pressure in the vicinity of the ultraviolet irradiation unit 4 is set to be lower than that near the site to be cleaned of the substrate K. It is also possible to further reduce ultraviolet absorption by oxygen molecules in the vicinity of the ultraviolet irradiation unit 4. It is also possible to control the oxygen partial pressure by mixing an inert gas and oxygen gas or directly jetting them.
[0067]
【The invention's effect】
  As described above in detail, the present inventionCleaning equipmentAccording to the invention, the oxygen partial pressure is set at a low cost, the UV processing time is shortened, and the work efficiency of the ultraviolet cleaning can be improved while performing sufficient decomposition removal cleaning.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a cleaning device according to a first embodiment of the present invention.
2 is a cross-sectional view taken along line II-II in FIG.
FIG. 3 is a plan view showing the cleaning apparatus of FIG. 1;
4 is a spectral distribution diagram of ultraviolet rays emitted from the ultraviolet light source 42 of FIG. 1; FIG.
FIG. 5 is a graph showing the relationship between the oxygen partial pressure near the site to be cleaned in the cleaning process and the contact angle on the surface of the substrate K after the cleaning process.
FIG. 6 is a graph showing the relationship between the partial pressure of oxygen near the site to be cleaned in the cleaning process and the contact angle of the surface of the substrate K after the cleaning process.
FIG. 7 is a schematic diagram for explaining a contact angle.
FIG. 8 is a perspective view showing a second embodiment of the cleaning apparatus according to the present invention.
9 is a cross-sectional view taken along line IX-IX in FIG.
10 is a plan view showing the cleaning device of FIG. 8. FIG.
FIG. 11 is a plan view showing a schematic configuration of a cleaning device according to a third embodiment of the present invention.
[Explanation of symbols]
K ... Substrate (object to be cleaned)
1 ... UV cleaning nozzle (cleaning device)
2 ... Cleaning gas supply nozzle
3. Cleaning process gas discharge nozzle
4 ... UV irradiation part
5, 5 '... Cleaning gas supply unit
6, 6 '... Cleaning gas discharge part
7 ... Cleaning gas supply nozzle (bottom)
8 ... Cleaning gas discharge nozzle (bottom)
42 ... UV light source

Claims (8)

During the atmospheric pressure, it was provided a cleaning gas supply means for setting the range of from 20Pa oxygen partial pressure in the cleaning region near the object to be cleaned 15 kPa, an ultraviolet light source for irradiating ultraviolet rays the to be cleaned sites, ,
The cleaning gas supply means mixes an inert gas and air to adjust a cleaning gas whose oxygen partial pressure is set in a range of 20 Pa to 15 kPa, and the cleaning gas supplied from the mixing unit It consists of a nozzle part that is ejected to the part to be cleaned ,
The cleaning apparatus according to claim 1, wherein the ultraviolet light source generates active oxygen in a cleaning gas supplied from the cleaning gas supply means and in the vicinity of the portion to be cleaned by the ultraviolet light irradiated from the light source . The cleaning gas supply means sets an oxygen partial pressure in the vicinity of the site to be cleaned within a range of 20 Pa to 2 kPa, and the mixing unit mixes an inert gas and air to set an oxygen partial pressure of 20 Pa to 20 Pa. The cleaning apparatus according to claim 1, wherein the cleaning gas is adjusted to a range of 2 kPa. The ultraviolet light source is disposed in a sealing portion filled with an inert gas, and the vicinity of the site to be cleaned and the light source between which the oxygen partial pressure is set in the range by the cleaning gas supply means cleaning apparatus according to claim 1 or claim 2, characterized in that the sealing portion is present. The cleaning gas supply means, the cleaning device according to claim 1 or claim 2, characterized in that it has an inert gas supply unit for ejecting an inert gas into the vicinity of the cleaning site. The ultraviolet light source, cleaning apparatus according to claim 1 or claim 2, characterized in that it is a xenon excimer light source. Cleaning apparatus according to claim 1 or claim 2, characterized in that the suction removal means for removing sucking the cleaning process gas washing the object to be cleaned sites from the cleaning site near provided. Have the ultraviolet light source is 2.0 mW / cm ² or more outputs, and wherein the distance between the ultraviolet light source and the object to be cleaned site, according to claim 1 or to no 1mm, characterized in that it is set in the range of 10mm The cleaning apparatus according to claim 2 . The cleaning apparatus according to claim 7 , further comprising a distance adjusting unit that adjusts a distance between the portion to be cleaned and the ultraviolet light source.

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