JP3602419B2 - Resist coating method, resist coating apparatus, mask pattern forming method, and liquid crystal substrate pattern forming method - Google Patents

Description

【００９９】
表１に示すように、排気口１２に逆止弁が装着されていない場合（図１０の場合）は、レジスト膜厚の平均値が３０６４．２オングストローム、８０ｍｍ×８０ｍｍの範囲内でのレンジが２２．６オングストローム、１３２ｍｍ×１３２ｍｍの範囲内でのレンジが３６．０オングストロームであった。これに対して、実施の形態５の場合（図１１の場合）は、レジスト膜厚の平均値が３０６６．１オングストローム、８０ｍｍ×８０ｍｍの範囲内でのレンジが１２．６オングストローム、１３２ｍｍ×１３２ｍｍの範囲内でのレンジが１３．４オングストロームであった。
【０１００】
上記の結果より、排気口１２に逆止弁１４が装着されると、８０ｍｍ×８０ｍｍの範囲内でも、１３２ｍｍ×１３２ｍｍの範囲内でも、レジストの塗布均一性が向上することが確認された。このように、逆止弁１４により空気の逆流を防ぐと、レジスト膜厚の均一性を顕著に向上させることができる。
【０１０１】
次に、図１２を参照して、マスク基板１６にマスクパターンを形成する方法について説明する。
【０１０２】
図１２（ａ）は、矩形のマスク基板１６上に、上記の手順で、レジスト３２（東京応化工業製：ＥＰ−００２）が、３０００オングストロームの膜厚で塗布された後の状態を示す。以下、マスク基板３２は、図１２（ａ）に示すように、石英等からなる透明基板３４と、Ｃｒ等からなる遮光膜３６の積層構造であるものとする。
【０１０３】
図１２（ｂ）に示すように、レジスト３２は、ＥＢ描画、ベーキング、および現像の処理に付されることにより所望の形状にパターニングされる。レジスト３２のＥＢ描画は、東芝機械製の加速電圧５０ｋＶ描画装置を使用して行った。ベーキング処理は１００℃で８分間実行される。また、現像処理は、マスク基板１６が２３℃にクーリングされた後に、東京応化工業製の現像液ＮＭＤ−３（２．３８％）を使用して６０秒間行われる。現像処理が終了すると、マスク基板１６を乾燥させるためのスピン乾燥が行われる。
【０１０４】
図１２（ｃ）に示すように、パターニングされたレジスト３２をマスクとして、遮光膜３６のドライエッチングが行われる。遮光膜３６のエッチングは、塩素ガスおよび酸素ガス雰囲気中で以下の条件に従って行われる。その結果、遮光膜３６は、レジスト３２と同様にパターニングされる。
・バイアス電圧：２０Ｗ
・アンテナパワー：０．５ｋＷ
・全ガス流量１００ｓｃｃｍ（塩素ガス８０ｓｃｃｍ、酸素ガス２０ｓｃｃｍ）
・圧力０．６８Ｐａ
・エッチング時間：７２０ｓｅｃ
【０１０５】
図１２（ｄ）に示すように、レジスト３２は遮光膜膜３６の上部から剥離される。次いで、マスク基板１６の洗浄および乾燥が実行されることにより、所望のマスクパターンを有するマスク基板１６が形成される。
【０１０６】
このようにして作製したマスクパターンの面内寸法ばらつきを以下の手順で測定した。すなわち、６０２５基板のパターン形成領域（１３２ｍｍ×１３２ｍｍ）に、２μｍの十字パターンを１６９点（１３点×１３点）作製する。次に、Ｎｉｋｏｎ製の光波干渉計ＸＹ−６ｉを用いて十字パターンの寸法精度を測定する。その結果、マスク基板１６上のパターン寸法のばらつき値はＸ・Ｙ方向ともに１２ｎｍ（３σ値）であった。この値は、次世代マスクに要求される寸法精度として十分な値である。このように、実施の形態５のマスクパターン形成方法によれば、レジストの膜厚が均一であることから、極めて優れたパターン寸法精度を実現することができる。
【０１０７】
ところで、上記の実施形態においては、マスク基板１６が備える遮光膜３６をＣｒで形成することとしているが、遮光膜３６の材質はこれに限定されるものではない。より具体的には、遮光膜３６は、ＡｌＳｉ、ＭｏＳｉ、ＷＳｉ、ＴｉＳｉ、ＮｉＳｉ、ＺｒＳｉなどの金属膜、またはこれらの混合物を用いて形成してもよい。
【０１０８】
また、本発明は、エッチングガス種をＣＦ_４／Ｏ_２またはＳＦ_６／Ｏ_２に変更することなどにより、ハーフトーン位相シフト膜であるＭｏＳｉＯＮ、ＭｏＳｉＮ、ＺｒＳｉＯ膜、ＣｒＦ膜、ＣｒＦＯ膜およびＴａＳｉＯ膜、ＴｉＳｉＯＮ膜等にも適用することができる。
【０１０９】
また、上記の実施形態においては、６インチのマスク基板（６０２５基板）が用いられているが、本発明は、次世代のマスク基板、すなわち、一辺の長さが２３０ｍｍであり、９ｍｍの厚さを有するマスク基板にも適用することができる。
【０１１０】
また、上記の実施形態においては、レジスト３２を塗布する矩形の基板がマスク基板１６の限定されているが、本発明の適用はこれに限定されるものではない。すなわち、本発明のレジスト塗布方法は、液晶ディスプレイ用の矩形の液晶基板、特に大型の液晶基板に所望のパターンを形成する際に適用しても良い。この場合、液晶基板の周辺部におけるレジスト膜厚の均一性を向上させることができる。
【０１１１】
また、上記の実施形態においては、レジスト３２を塗布する基板が矩形のマスク基板１６の限定されているが、本発明の適用はこれに限定されるものではなく、８インチウエハや３００ｍｍウエハなど、円形の基板に対して本発明を適用することとしてもよい。この場合、それらのウェハの周辺部における膜厚分布の均一性を向上させることができる。
【０１１２】
また、上記の実施形態においては、レジスト３２として東京応化工業製ＥＰ−００２を使用したが、レジスト３２はこれに限定されるものではなく、他のＥＢレジスト、またはＫｒＦ或いはＡｒＦ用のエキシマレーザー用レジストを使用してもよい。
【０１１３】
更に、上記の実施形態においては、基板上にレジストを塗布することとしているが、本発明の適用はレジストに限定されるものではなく、ＳＯＧ（Ｓｐｉｎ Ｏｎ Ｇｌａｓｓ）等を基板に塗布する際に、本発明の塗布方法を用いてもよい。
【０１１４】
実施の形態６．
図１３（Ａ）ないし（Ｆ）および図１４（Ａ）ないし（Ｄ）は、本発明の実施の形態６におけるＨＴ膜形成方法の工程を示す。図１３（Ａ）ないし（Ｆ）、図１４（Ａ）ないし（Ｄ）において図４（実施の形態４）と同じ符号を付した部分は同じ要素を指すため説明は省略する。本実施の形態６は、ＨＴ膜パターンを形成する方法である。実施の形態４と同様の工程については説明を省略する。本実施の形態６の膜構造としては、図１３（Ａ）ないし（Ｆ）に示されるような、
（１）レジスト４３０／Ｃｒ４２０／ＨＴ４１５／基板（Ｑｚ）４１０
と、図１４（Ａ）ないし（Ｄ）に示されるような、
（２）レジスト４３０／ＨＴ４１５／基板（Ｑｚ）４１０
との２つがある。ここで基板Ｑｚは透明基板等である。
【０１１５】
（１）の場合は、図１３（Ａ）ないし（Ｆ）に示されるように、レジスト４３０をパターニング後、このパターン４３５をマスクとしてＣｒ４２０をパターニングして、その後にＨＴ膜４１５をＣｒパターン４２５をマスクとしてエッチングする。Ｃｒパターン４２５の意味はマスクの遮光用の枠の形成のためである。遮光用の枠はパターン領域４１３の周囲にある。
【０１１６】
図１３（Ｆ）に示されるように、再度レジスト塗布して描画して枠以外の部分のレジストを除去してから、ウエットエッチング等によりＣｒを除去する。
【０１１７】
（２）の場合は、図１４（Ａ）ないし（Ｄ）に示されるように、レジスト４３０をパターニング後に、このパターン４３５をマスクにＨＴ４１５をエッチングする。このときはＨＴ膜４１５をパターン領域４１３外ではｄｏｔパターンとして遮光部を形成する。微細なｄｏｔパターンは０．３μｍ以下である。図１４（Ｄ）に示されるように、ＨＴ４１５は単層で済むという利点がある。
【０１１８】
（１）のＣｒエッチングは実施の形態４のＣｒ膜エッチングと同じ条件である。ＨＴエッチングは、ＮＬＤＥ−９０３５（アルバック成膜製）を使用して、圧力０．６８Ｐａ、ガスＣＦ_４／Ｏ_２＝１００ｓｃｃｍ：５ｓｃｃｍ、時間３５０ｓｅｃで行う。均一性はＣｒがそのまま転写されるため、ほぼ同じ精度、１３ｎｍ（３Ｏ）で形成されている。
【０１１９】
【発明の効果】
以上説明したように、本発明のレジスト塗布方法、レジスト塗布装置およびレジスト塗布方法を用いたマスクパターン形成方法によれば、２枚の同一材料からなる中央部フィルタと周辺部フィルタとを重ね合わせて用いることにより、周辺部フィルタにおけるフィルタ密度を中央部フィルタにおけるフィルタ密度よりも疎とすることができるため、矩形基板四辺部におけるレジスト乾燥速度を速くすることができる。この結果、マスク塗布スループット面での効率を高めることができ、矩形基板の四辺周辺におけるレジストの膜厚差を低減させた高精度のレジスト塗布を行なうことができるレジスト塗布方法、レジスト塗布装置およびレジスト塗布方法を用いたマスクパターン形成方法を提供することができる。
【０１２０】
さらに本発明によれば、矩形状のフィルタを用いることにより、マスクパターン領域が拡大した場合であっても、フィルタ自身の重みによる中心部分の撓みを低減させることができるレジスト塗布方法、レジスト塗布装置およびレジスト塗布方法を用いたマスクパターン形成方法を提供することができる。
【０１２１】
さらにこの発明は、以上説明したように構成されているので以下に示すような効果を奏する。
【０１２２】
本発明によれば、回転カップの排出口において空気の逆流が生ずるのを防ぐことができる。このため、本発明によれば、回転中の回転カップが減速し始めた後に、排気口から逆流する空気によって基板端部に溜まっているレジストが中心方向に吹き飛ばされることがない。従って、本発明によれば、基板の中心部、より具体的には基板のパターン形成領域の全域に、均一な膜厚でレジストを塗布することができる。
【０１２３】
本発明によれば、基板を含む第１の空間に、フィルタを介して大気圧以上の圧力を導入することができる。この場合、第１の空間に対する空気の流入が緩やかになるため、基板表面に塗布されたレジストをゆっくりと乾燥させることができる。従って、本発明によれば、乾燥ムラに起因するレジスト膜厚のばらつきを防止して、均一な膜厚を有するレジスト膜を形成することができる。
【０１２４】
本発明によれば、リーク用弁を開弁させるだけで、容易に第２の空間に大気圧を導入することができる。このため、本発明によれば、簡単な作業で、レジストをゆっくりと乾燥させることができる。
【０１２５】
本発明によれば、マスク基板の表面、すなわち、遮光膜の表面に均一な膜厚でレジスト膜を形成することができる。このため、本発明によれば、そのレジスト膜および遮光膜を高い精度でパターニングして、精度の良いマスクパターンを形成することができる。
【０１２６】
本発明によれば、矩形の液晶基板の表面に均一な膜厚でレジスト膜を形成することができる。このため、本発明によれば、そのレジスト膜を高い精度でパターニングして、液晶基板上に、精度良く所望のパターンを形成することができる。
【図面の簡単な説明】
【図１】本発明の実施の形態１におけるレジスト塗布装置を示す図である。
【図２】本発明の実施の形態１で用いるフィルタ１４０の形状の一例を示す図である。
【図３】本発明の実施の形態２におけるレジスト塗布方法を示す図である。
【図４】本発明の実施の形態４におけるマスクパターン形成方法の工程を示す図である。
【図５】本発明の実施の形態５のレジスト塗布装置の構成を表す図である。
【図６】本発明の実施の形態５のレジスト塗布装置を図５に示すＩＩ−ＩＩ矢視で表した図である。
【図７】本発明の実施の形態５のレジスト塗布装置が備える多層構造フィルタの平面図である。
【図８】本発明の実施の形態５のレジスト塗布装置の動作を説明するための図である。
【図９】本発明の実施の形態５のレジスト塗布装置によるレジスト塗布手順を説明するための図である。
【図１０】排気口に逆止弁が装着されていない場合に得られるレジスト膜の均一性を表す測定結果である。
【図１１】本発明の実施の形態５のレジスト塗布装置により形成されるレジスト膜の均一性を表す測定結果である。
【図１２】マスク基板にマスクパターンを形成する手順を説明するための図である。
【図１３】本発明の実施の形態６におけるＨＴ膜形成方法の工程を示す図である。
【図１４】本発明の実施の形態６におけるＨＴ膜形成方法の工程を示す図である。
【図１５】従来の金属焼結体を用いてレジストの乾燥速度を制御する方法の概要を示す図である。
【図１６】従来の円形の形状を有する金属焼結体フィルタを示す図である。
【図１７】従来のレジスト塗布装置によるレジスト塗布手順を説明するための図である。
【符号の説明】
１０ 回転カップ、 １２ 排気口、 １４ 逆止弁、 １６ マスク基板、１８ レジスト塗布ユニット、 ２０ 多層構造フィルタ、 ２２，３２０ 周辺部フィルタ、 ２４ 中心部フィルタ、 ２８ 上蓋部、 ３０ リーク用弁、 ３２，５００ レジスト、 ３４，４１０ 透明基板、 ３６ 遮光膜、１００ レジスト廃液および有機物排気部、 １１０，５１０ 矩形基板、 １２０ 回転カップユニット、 １３０ レジスト滴下ユニット、 １４０ フィルタ、 １５０ 上回転カップ、 ３１０ 中央部フィルタ、 ４１３ パターン領域、 ４１５ ＨＴ膜、 ４２０ 遮光膜Ｃｒ膜、 ４３０ ＥＢレジスト膜、 ４２５ 遮光膜Ｃｒ膜パターン、 ４３５ ＥＢレジストパターン、 ５２０ マスクパターン領域、 ６１０ 金属焼結体空孔フィルタ。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a resist coating method, a resist coating device, a mask pattern forming method using the resist coating method, and a pattern forming method for a liquid crystal substrate, and more particularly to a resist coating method for coating a mask pattern with a resist, a resist coating device, and a resist coating method. Pattern forming method using a resist, a resist coating apparatus, a resist coating method, a mask pattern forming method, and a pattern forming method for a liquid crystal substrate suitable for accurately forming a mask pattern of an exposure mask used in a semiconductor manufacturing process And how to.
[0002]
[Prior art]
Conventionally, a lithography technique has been used to form a mask pattern for a normal exposure mask. In this case, a resist is applied on the substrate of the exposure mask, and the resist is selectively exposed to the exposure mask coated with the resist using a laser beam or an electron beam (EB) drawing apparatus, and developed. By doing so, a resist pattern was formed on the mask substrate for exposure.
[0003]
In recent years, the minimum pattern size on a mask has been reduced due to a decrease in mask magnification (from 5 times to 4 times) and a demand for proximity effect correction to prevent optical image deterioration during mask pattern transfer. That is, a minimum line width of 0.1 to 0.2 μm on a mask substrate has been required. For this reason, for the formation of a mask pattern, in the case of a 130 nm design rule, a value of 13 to 15 nm in 3σ (σ: standard deviation) has been required as a dimension variation on a mask substrate. In the process of applying a resist on a mask substrate, a very small value of a range of 40 ° has been required as a target value of the uniformity. Further, in the case of a 6-inch mask substrate (152 mm × 152 mm × 6.35 mm), uniformity over a wide area of 132 mm × 132 mm has been required for a pattern formation region on the mask substrate. However, when the resist is applied to the mask pattern, since the shape of the mask substrate is rectangular unlike the case where the resist is applied to the silicon Si wafer, a variation in film thickness called fringe is formed at the four corners of the mask substrate. There has been a problem that a large portion is formed.
[0004]
In order to solve the problem of the formation of fringes described above, recently, a rotating cup type mask resist coating apparatus has been developed. This rotary cup type resist coating apparatus introduces a mask substrate into a cylindrical container called a rotating cup and simultaneously rotates the mask substrate and the cylindrical container to reduce friction between the mask substrate and air. An attempt was made to solve the problem that the above-described fringe was formed by forming a state. However, since the coating is performed in a closed space, there is a new problem that a difference in the film thickness of the resist locally occurs on the mask substrate due to drying unevenness when the resist is dried.
[0005]
On the other hand, in the case of a 6-inch mask substrate as described above, it is necessary to secure a large pattern formation area of 132 mm × 132 mm on the mask substrate. The size of the pattern formation region is required because a mask is used in an exposure apparatus generally called a scanner, and a reduction projection lens used in the scanner cannot be enlarged due to the influence of aberration and the like. At present, the short side is 100 mm on the mask and the remaining long side is 132 mm on the mask, and the mask and the wafer are moved synchronously to reduce aberration.
[0006]
In order to reduce the dimensional variation of the mask pattern over the entire area of the above-described wide pattern formation area, it is necessary to apply a resist with a uniform film thickness over the entire area of the pattern formation area. More specifically, in order to satisfy the above requirement regarding the dimensional variation, in the step of applying the resist on the mask substrate, the range of the resist film thickness over the entire pattern formation region, that is, the maximum film thickness of the resist A very small target value of 40 angstrom or less is required for the difference between the minimum and the minimum film thickness.
[0007]
When a resist film is formed on a Si substrate, usually, the resist is applied to the surface of the Si substrate while rotating the substrate around a central axis. In this case, the resist is uniformly spread by the centrifugal force, and a resist film having a uniform thickness is formed. Incidentally, the mask substrate has a rectangular shape unlike the Si wafer. For this reason, when the mask substrate is rotated around the central axis, friction with air occurs near the four corners due to the thickness of the mask substrate.
[0008]
When a resist is applied on a mask substrate under a situation where friction with air largely acts only in the vicinity of the four corners, the resist has a different spreading tendency in the vicinity of the center of the mask substrate and in the vicinity of the four corners. For this reason, if the resist is applied to the mask substrate in the same manner as in the case of applying the resist to the Si wafer, portions having large thickness variations called fringes will be formed at the four corners of the mask substrate.
[0009]
In order to solve the above-mentioned problems, a rotating cup type resist coating apparatus has recently been developed. This apparatus introduces a mask substrate into a cylindrical container called a rotating cup, and applies a resist onto the mask substrate while simultaneously rotating the mask substrate and the cylindrical container. According to the resist coating apparatus of the rotating cup type, the mask substrate can be rotated without causing a large friction between the rectangular mask substrate and the air existing around the mask substrate. Therefore, this device is effective in solving the fringe problem described above.
[0010]
However, as described above, in the rotating cup type apparatus, the application of the resist is performed in an enclosed space called a rotating cup, so in the rotating cup type apparatus, the resist applied on the mask substrate is dried when the resist is dried. However, there is a problem that a local difference in film thickness is likely to occur due to drying unevenness.
[0011]
In order to solve the problem that the thickness difference of the resist locally occurs on the mask substrate, a method of controlling the drying speed of the resist using a metal sintered body has recently been proposed (Japanese Patent Laid-Open No. -286510 and JP-A-10-314653). This method is intended to reduce so-called wind ripple unevenness that occurs on the mask substrate during drying by restricting the introduction of outside air onto the mask substrate by extending the metal sintered body and extending the resist drying time. is there. The wind ripple unevenness has a shape similar to a wind ripple on sand, and is considered to be likely to occur when the drying time of the resist is too early.
[0012]
FIG. 15 shows an outline of a method of controlling a resist drying rate using a conventional metal sintered body proposed in Japanese Patent Application Laid-Open No. 10-286510. As shown in FIG. 15A, first, a resist 500 is dropped on a mask substrate (rectangular substrate) 510, and then, as shown in FIG. 15B, the rectangular substrate 510 is rotated and dropped. A resist 500 is spin-coated on a mask pattern area (132 mm × 132 mm square) 520. Finally, as shown in FIG. 15C, the resist 500 spin-coated on the rectangular substrate 510 via the metal sintered body 530 is dried. However, the metal sintered body 530 used in the method proposed in Japanese Patent Application Laid-Open No. H10-286510 has a void ratio, which is a ratio of holes for taking in outside air and drying the resist 500 spin-coated on the rectangular substrate 510. Since the porosity is uniform and the above-described method is performed using one metal sintered body 530, it takes a long time to dry the resist, and there is a problem in mask coating throughput. In addition, as shown in FIG. 15C, in the vicinity of the four sides of the rectangular substrate 510, the resist 500 that has not been shaken during the spin coating returns to the center direction of the rectangular substrate 510 as the drying time increases ( There is a problem that a portion having a large difference in the thickness of the resist is formed with a wide width around the four sides of the resist 505) and the rectangular substrate 510.
[0013]
In the method proposed in Japanese Patent Laid-Open No. Hei 10-314653, spin coating is performed, and after the upper spin cup that covers the spin cup is opened, outside air is passed from the side wall of the spin cup through a metal sintered body or the like into the spin cup. Is introduced into the resist-coated substrate. However, the above-described configuration is mechanically complicated, and the rapid flow of air when the upper rotating cup is opened after resist application because the filter does not exist between the upper rotating cup and the resist-coated substrate. Is generated on the resist-coated substrate, which causes a problem in that the liquid surface of the resist that has not been dried is vibrated, and the uniformity of the resist coating is deteriorated. For this reason, in the case of a rectangular substrate such as a mask substrate, when the mask pattern region is enlarged, there is a problem that the mask pattern dimension is deteriorated due to the deterioration of the uniformity of the resist coating on the four sides of the rectangular substrate.
[0014]
Even when a filter is used together with the upper rotating cup, the conventional filter has a metal sintered body having a circular shape as shown in FIG. 16 because the upper rotating cup and the like have a cylindrical shape. The pore filter 610 was used. For this reason, in the center portion of the metal sintered body filter 610, bending occurs due to the weight of the metal sintered body itself, and when the resist is dropped on the rectangular substrate, there is a problem that the bent filter and the resist come into contact with each other. Had occurred. Therefore, for example, when a resist is applied to a mask substrate that has been enlarged (230 mm on a side), if the metal sintered body is simply enlarged, the metal sintered body itself is further weighted by the weight of the enlarged metal sintered body itself. There has also been a problem that the central portion of the body is lowered due to the bending, so that the body easily comes into contact with the resist.
[0015]
The above-mentioned technique of controlling the drying speed of the resist by introducing air into the inside of the rotating cup through the metal sintered body after the application of the resist is completed (Japanese Patent Application Laid-Open Nos. 10-286510 and 10-314653). New problems have been discovered through its use. That is, the rotating cup type apparatus, after dropping the resist on the mask substrate, increases the rotation speed of the rotation cup at a predetermined acceleration, and after maintaining the predetermined rotation speed for a predetermined time, at a predetermined deceleration. Decrease the speed.
[0016]
The above-described spin coating of the resist is performed with the opening of the spin cup closed. The rotating cup is provided with an outlet for discharging the resist, and when the rotation of the rotating cup is started, the resist and the air are discharged from the outlet. Therefore, during rotation of the rotating cup, its internal pressure is lower than the atmospheric pressure.
[0017]
When the rotation of the rotation cup is rotated at a predetermined speed for a certain period of time and the rotation is started to be decelerated, a backflow of air occurs at the resist discharge hole due to a pressure difference between the inside and outside of the rotation cup. FIGS. 17A to 17C schematically show the above phenomenon.
[0018]
The resist accumulated on the peripheral end surface of the rectangular mask substrate is blown off toward the center of the mask substrate during the spin coating process mainly due to the above-mentioned air flowing backward when the rotation is decelerated. As a result, a large thickness unevenness is likely to be formed on the resist applied on the mask substrate, especially in the peripheral portion. Such unevenness in the thickness of the resist causes a dimensional error when a fine pattern is formed in a range of 132 mm × 132 mm on the photomask. As described above, the conventional rotary cup type apparatus still has a problem in accurately forming a mask pattern on a mask substrate.
[0019]
[Problems to be solved by the invention]
As described above, in the conventional mask resist coating apparatus of the rotating cup type, the porosity is uniform and one metal sintered body is used. was there. Furthermore, since the resist that has not been shaken off during the spin coating returns to the center of the rectangular substrate as the drying time increases, a portion having a large difference in the thickness of the resist around the four sides of the rectangular substrate is formed with a wide width. was there.
[0020]
Furthermore, in the conventional rotary cup type mask resist coating apparatus, in addition to the complicated mechanical structure, the uniformity of resist coating deteriorates due to the rapid flow of air generated on the resist coating substrate. Therefore, when the mask pattern area is enlarged, there is a problem that the mask pattern dimension is deteriorated due to the deterioration of the uniformity of the resist coating on the four sides of the rectangular substrate. Even when a filter is used together with the upper rotating cup, the conventional filter simply has a large metal sintered body when the mask substrate is enlarged because the upper rotating cup etc. had a cylindrical shape. Then, there has been a problem that the weight of the enlarged metal sintered body itself causes the central portion thereof to be bent and come into contact with the resist.
[0021]
Therefore, an object of the present invention is to solve the above-described problem, and the efficiency of the mask coating throughput is improved by quickly drying the resist on the four sides of the mask substrate, thereby improving the four sides of the mask substrate. A resist coating method, a resist coating apparatus, and a resist coating method capable of performing high-precision resist coating in which a resist in a portion is prevented from returning to the center direction of the rectangular substrate and a thickness difference of the resist around four sides of the mask substrate is reduced. An object of the present invention is to provide a mask pattern forming method using a resist coating method.
[0022]
A second object of the present invention is to provide a resist coating method, a resist coating apparatus, and a resist coating method capable of reducing the deflection of the central portion due to the weight of the enlarged metal sintered body itself even when the mask pattern region is enlarged. An object of the present invention is to provide a mask pattern forming method using a resist coating method.
[0023]
A third object of the present invention is to provide a rotating cup type resist coating apparatus and a resist coating method which can reduce the unevenness in the thickness of the resist generated on the peripheral portion of a rectangular mask substrate.
[0024]
A fourth object of the present invention is to provide a pattern forming method capable of accurately forming a desired pattern on a rectangular mask substrate or a rectangular liquid crystal substrate by using the above-described resist coating method.
[0025]
The resist coating method according to the first aspect of the present invention includes a step of introducing a rectangular substrate into a column-shaped container having an open top, and a step of dropping and supplying a resist onto the rectangular substrate introduced into the container. A step of covering an open upper part of the container part with a rectangular filter part, a step of covering the container part with a lid that can be opened and closed via the filter part, and the lid part covers the filter part. Closing the container portion through, and rotating the rectangular substrate, the filter portion and the lid portion together with the container portion around an axis in the column direction of the columnar container portion, and dropping the droplet onto the rectangular substrate. A coating step of coating the supplied resist, and a drying step of drying the resist applied on the rectangular substrate by opening only the lid while the filter unit covers the open top of the container unit And For exampleThe rectangular substrate is formed of a light shielding film or a MoSiON film made of a MoSi (molybdenum silicide) film formed on a quartz substrate, _Two A translucent film selected from the group consisting of a film, a TaSiO film, a ZrSiO film, a CrFO film, and a MoSiN film. In the dropping step, the resist dropping portion is formed on the quartz substrate. After the resist for the electron beam is dropped on the light-shielding film or the translucent film, the transparent substrate, the filter unit, and the lid are rotated together with the container around the axis in the column direction of the columnar container.Things.
[0026]
The resist coating of the invention according to claim 2apparatusIsA rectangular substrate, a column-shaped container portion having an upper portion opened and the rectangular substrate introduced therein, a resist dropping portion for dropping a resist onto the rectangular substrate introduced into the container portion, and an opening in the container portion A rectangular filter part covering the upper part, a lid part that can open and close the container part through the filter part, and a resist on the peripheral part of the rectangular substrate only from the peripheral part of the filter part. A gas introduction unit for introducing a gas higher in temperature than the gas introduced into the resist at the center of the rectangular substrate, and when applying the resist on the rectangular substrate, the gas was introduced into the container from the resist dropping unit. After the resist is dropped and supplied onto the rectangular substrate, the rectangular substrate, the filter unit, and the lid unit are connected to the column-shaped container unit with the lid unit closing the container unit via the filter unit. When the filter unit is rotated around the axis in the column direction together with the container unit to apply the supplied resist dripped onto the rectangular substrate, and to dry the resist applied on the rectangular substrate, the filter unit includes the container. Open only the lid while covering the open top of the partThings.
[0028]
Claim3The resist coating apparatus according to the aspect of the invention includes a rectangular substrate, a column-shaped container having an upper portion opened, and the rectangular substrate introduced therein, and a resist that drops a resist onto the rectangular substrate introduced into the container. A dripping unit, a rectangular filter unit that covers the open top of the container unit, and a lid unit that opens and closes the container unit via the filter unit,The filter unit, the filter density of the peripheral part is less than the filter density of the central part,When applying the resist on the rectangular substrate, after the resist is dropped from the resist dropping portion onto the rectangular substrate introduced into the container portion and supplied, the lid portion is connected to the container portion via the filter portion. In a closed state, the rectangular substrate, the filter unit and the lid unit are rotated together with the container unit around an axis in the column direction of the columnar container unit, and the resist supplied dropwise on the rectangular substrate is supplied. When applying and drying the resist applied on the rectangular substrate, only the lid is opened with the filter covering the open top of the container.
[0031]
Claim4The resist coating apparatus of the invention described inA rectangular substrate, a column-shaped container portion having an upper portion opened and the rectangular substrate introduced therein, a resist dropping portion for dropping a resist onto the rectangular substrate introduced into the container portion, and an opening in the container portion A rectangular filter portion that covers the upper portion, and a lid portion that opens and closes the container portion via the filter portion, wherein the filter portion has a rectangular shape similar to the shape of the rectangular substrate. It is provided in a state where the four sides of the filter unit and the four sides of the rectangular substrate coincide with each other, and when applying the resist on the rectangular substrate, the resist is introduced into the container from the resist dropping unit. After dropping and supplying a resist onto the rectangular substrate, the rectangular substrate, the filter unit and the lid unit are connected to the column-shaped container unit with the lid unit closing the container unit via the filter unit. Pillar style When the filter unit is rotated around the axis of the container unit, the supplied resist is applied dropwise onto the rectangular substrate, and the resist applied on the rectangular substrate is dried. Only the lid is opened while covering the opened upper part..
[0032]
Claim5The resist coating apparatus of the invention described in claim3 or 4, A rectangular supporting portion for supporting an edge portion of the filter portion may be further provided.
[0033]
Claim6The resist coating apparatus of the invention described in claim3-5In any one of the above, further comprising a gas introduction unit for introducing a gas higher in temperature than the gas introduced into the resist at the center of the rectangular substrate from only the periphery of the filter unit to the resist on the periphery of the rectangular substrate. Is what you can do.
[0034]
Claim7The resist coating apparatus of the invention described in claim2-6In any one of the above, the filter section can be formed using an aluminum sintered body.
[0035]
Claim8The resist coating apparatus of the invention described in claim2-6In any one of the above, the filter portion can be formed using porous glass or a ceramic material.
[0041]
Claim9The described invention is a resist coating method for coating a resist on the surface of a substrate, wherein the step of holding the substrate in a hollow rotating cup rotatable around a central axis, and held in the rotating cup Applying a resist on the surface of the substrate, and closing the opening provided by the rotating cup for loading and unloading the substrate with a lid, and rotating the cup from its internal space to its external space. In a state where a check valve that allows only the flow of fluid from the inside of the rotating cup to the outside is attached to a discharge port provided for discharging extra resist, the rotation cup is held therein together with the rotation cup. Rotating the lid, which closes the substrate and the opening thereof, and removing the substrate from the inside thereof after the rotation of the rotating cup is stopped.Wherein the internal space of the rotary cup is divided into a first space including the substrate by a filter and a second space not including the substrate, and the rotation of the rotary cup is sufficiently decelerated. The method further comprises the step of introducing a pressure equal to or higher than the atmospheric pressure into the second space, wherein the rotary cup or the lid is provided with a vent and a leak valve for opening and closing the vent. Introducing the pressure equal to or higher than the atmospheric pressure into the second space, wherein the step of opening the leak valve is performed.It is characterized by including.
[0043]
Claim10The invention described in the claims9Wherein the filter is made of a porous glass or a ceramic material.
[0045]
Claim11The described invention is a method for forming a mask pattern of an exposure mask used in a semiconductor manufacturing process, wherein the mask pattern comprises a light-shielding film or a translucent film on a surface of a transparent substrate.9 or 10Applying a resist by the described resist application method, patterning the resist into a desired pattern, and etching the light-shielding film or the translucent film using the patterned resist as a mask. It is characterized by the following.
[0046]
Claim12The invention described is a method for forming a desired pattern on a rectangular liquid crystal substrate, and further comprising:9 or 10Applying a resist by the described resist coating method, patterning the resist into a desired pattern, and patterning a desired pattern on the liquid crystal substrate using the patterned resist as a mask. It is characterized by the following.
[0047]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, common elements are denoted by the same reference numerals, and redundant description is omitted.
[0048]
Embodiment 1 FIG.
FIG. 1 shows a resist coating apparatus according to Embodiment 1 of the present invention. In FIG. 1, reference numeral 110 denotes a rectangular substrate such as a mask substrate, 120 denotes a cylindrical rotating cup unit having the rectangular substrate 110 mounted therein, and 130 denotes a resist on the rectangular substrate 110 mounted in the rotating cup unit 120. , A resist waste liquid and organic substance exhaust unit for discarding resist waste liquid and organic matter in the rotating cup unit 120, a filter 140 for taking outside air into the rotating cup unit 120, and a rotating cup unit 150. An upper rotating cup that closes the unit 120 via the filter 140.
[0049]
As shown in FIG. 1, a rectangular substrate 110 is placed inside a cylindrical rotating cup unit 120, and a resist is dropped from a resist dropping unit 130 and supplied in the same manner as in a conventional resist dropping method. Next, the filter 140 and the upper rotating cup 150 are closed. In this closed state, the rectangular substrate 110, the filter 140, and the upper rotating cup 150 are rotated together with the rotating cup unit 120 to apply the resist dropped and supplied to the rectangular substrate 110. By providing the filter 140, after the resist application is completed, it is possible to dry the resist applied on the rectangular substrate 110 by opening only the upper rotating cup 150 while leaving the filter 140. Compared with the case where the filter 140 is not provided, a sharp air flow when the upper rotating cup 150 is opened does not occur on the resist-coated substrate 110, so that the uniformity of the resist coating can be prevented from deteriorating.
[0050]
As a material of the above-described filter 140, a filter that is rigid even though it is thin, has holes for taking in outside air, and does not generate dust is preferable. For example, an aluminum sintered body used for a slow vent portion of a vacuum device can be applied as the filter 140.
[0051]
FIG. 2 shows an example of the shape of the filter 140 used in the first embodiment of the present invention. As shown in FIG. 2, the filter 140 has two types of rectangular central filters 310 and peripheral portions having a shape similar to the rectangular substrate 110 installed in the same direction as the four sides of the rectangular substrate 110. A filter 320 is used. More specifically, the peripheral filter 320 has a lower filter density than the central filter 310 in order to promote drying of the resist in the peripheral portion of the rectangular substrate 110. Here, the filter density is an amount that is inversely proportional to the above-mentioned porosity, and the filter density decreases as the number of porosity increases. The central filter 310 can be formed, for example, by overlapping a small filter made of the same material as the peripheral filter 320 on the central portion of the peripheral filter 320. As a result, since the peripheral portion where the filter density is low becomes easier to dry than the central portion, the problem of the increase in the resist film thickness at the four sides of the rectangular substrate due to the long conventional drying time is solved. be able to.
[0052]
By making the opening of the filter 140 rectangular, the peripheral portion of the filter 140 can be supported, so that the bending of the filter can be reduced from about 3 mm to about 1 mm. .
[0053]
Instead of the aluminum sintered body described above, porous glass can be applied as the filter 140.
[0054]
As described above, according to the first embodiment, two types of rectangular peripheral filters 320 and central filters 310 are provided between the rotary cup unit 120 on which the rectangular substrate 110 is mounted and the upper rotary cup 150. As a result, the filter density at the peripheral portion can be made lower than the filter density at the central portion, so that the peripheral portion becomes easier to dry than the central portion, and the conventional rectangular substrate has a longer drying time than the four sides of the rectangular substrate. Can be solved.
[0055]
Embodiment 2 FIG.
FIG. 3 shows a resist coating method according to the second embodiment of the present invention. In FIG. 3, the portions denoted by the same reference numerals as those in FIG. 1 or FIG. In the second embodiment, the resist coating apparatus shown in the first embodiment is used. As shown in FIG. 3A, a resist 500 is first dropped on a rectangular substrate 110, and then the resist 500 shown in FIG. As shown in B), the resist 500 dropped by rotating the rectangular substrate 110 is spin-coated on the mask pattern area (132 mm × 132 mm square) 520. After the spin coating, as shown in FIG. 3C, the spin-coated resist 500 is dried using the above-described two types of filters 140 having a rectangular peripheral filter 320 and a central filter 310. Perform
[0056]
For the spin coating shown in FIG. 3C, EP-002 (manufactured by Tokyo Ohka Kogyo Co., Ltd .: resist viscosity 3.5 cp) can be used. The resist application conditions are as follows: the rising acceleration is 10,000 rpm / sec, the rotation is performed at 2500 rpm for 3 seconds, and the rotation is stopped at 0 rpm after 12.5 seconds at -200 rpm / sec. Thereafter, the upper rotating cup was opened or removed in a stopped state, and the resist applied on the rectangular substrate 110 was dried using the filter 140 by using the organic substance exhaustion of the rotating cup. By stopping the rotation of the rectangular substrate 110 during the drying of the resist, it was possible to reduce the unevenness in the film thickness during the drying of the resist due to the vibration caused by the rotation of the liquid surface of the resist applied on the rectangular substrate 110.
[0057]
Thereafter, a baking treatment was performed at 90 ° C. for 15 minutes, and then a cooling treatment was performed at 23 ° C. for 5 minutes. As a result, a portion having a large resist film thickness is conventionally formed in a portion from the rectangular substrate 110 to 10 mm, but according to the present embodiment, the portion can be reduced to about 5 mm. For example, in the case of a 6-inch mask substrate, the resist coating uniformity could achieve a range of about 30 mm (132 mm × 132 mm area) when the resist film thickness was 3000 mm. The use of the filter 140 makes it possible to reduce the drying speed, so that the resist can be coated with excellent uniformity so that drying unevenness or the like cannot be visually confirmed. Regarding the drying time, the conventional drying time of 4 minutes can be reduced to 2 minutes, and the efficiency in mask application throughput can be improved.
[0058]
In the second embodiment, a case has been exemplified in which the central filter 310 and the peripheral filter 320 made of the same material are overlapped with each other. However, when three or more filters of different materials are overlapped, Alternatively, the same effect can be obtained even with a single filter in which the holes at the center are made dense and the periphery is made sparse.
[0059]
As described above, according to the second embodiment, by using the resist coating apparatus shown in the first embodiment and stopping the rotation of the rectangular substrate 110 during the drying of the resist, the resist solution applied on the rectangular substrate 110 It is possible to reduce unevenness in film thickness when the resist is dried due to vibration caused by the rotation of the surface. Since the drying speed can be reduced by using the filter 140, it is possible to perform resist coating with excellent uniformity. The conventional drying time of 4 minutes can be reduced to 2 minutes, and the efficiency in mask application throughput can be improved.
[0060]
Embodiment 3 FIG.
The third embodiment uses the resist coating apparatus shown in the first embodiment, and selectively applies hot air only to the peripheral portion of the rectangular substrate 110 at the time of drying the resist. This is a resist coating method for further promoting the drying of the resist.
[0061]
The resist coating method in the third embodiment uses EP-002 (manufactured by Tokyo Ohka Kogyo Co., Ltd .: resist viscosity 3.5 cp) as in the resist coating method in the second embodiment, and the resist coating conditions are as follows. After setting the acceleration at the rise to 10000 rpm / sec and rotating at 2500 rpm for 3 seconds, -200 rpm. After 12.5 seconds, the rotation was stopped at 0 rpm. Thereafter, the upper rotating cup was removed, and dry nitrogen at 40 ° C. was applied only to the peripheral portion of the resist on the peripheral portion of the rectangular substrate 110 from the filter 320 to selectively dry the resist on the peripheral portion of the rectangular substrate 110. As described above, by stopping the rotation of the rectangular substrate 110 during the drying of the resist, the thickness unevenness during the drying of the resist due to the vibration caused by the rotation of the liquid surface of the resist applied on the rectangular substrate 110 is reduced. be able to.
[0062]
According to the third embodiment described above, a portion having a large resist film thickness is conventionally formed in a portion from the rectangular substrate 110 to 10 mm, but this can be reduced to about 5 mm. For example, in the case of a 6-inch mask substrate, the resist coating uniformity was able to achieve a range of about 30 mm (132 mm × 132 mm area) when the resist film thickness was 3000 mm. Since the drying speed can be reduced by using the filter 140, resist coating with excellent uniformity can be performed such that drying unevenness or the like cannot be visually confirmed. In the second embodiment, the drying time requires two minutes. In the third embodiment, the drying time can be reduced to one minute, and the effect of improving the throughput on the resist drying surface can be obtained.
[0063]
In the third embodiment, the case where the central filter 310 and the peripheral filter 320 made of the same material are superposed is exemplified, but when three or more filters of different materials are superposed, Alternatively, the same effect can be obtained even with a single filter in which the holes at the center are made dense and the periphery is made sparse.
[0064]
As described above, according to the third embodiment, the resist coating apparatus described in the first embodiment is used to selectively blow hot air only to the peripheral portion of the rectangular substrate 110 when the resist is dried. Thus, the drying time can be reduced from 2 minutes to 1 minute as compared with the second embodiment, and the efficiency in mask application throughput can be further improved.
[0065]
Embodiment 4 FIG.
In the fourth embodiment, a fine mask pattern is formed on a rectangular mask substrate using the resist coating apparatus described in the first embodiment and the resist coating method described in the second or third embodiment. Is the way.
[0066]
FIG. 4 shows steps of a mask pattern forming method according to the fourth embodiment of the present invention. In FIG. 4, portions denoted by the same reference numerals as those in FIGS. 1 to 3 have the same functions, and thus description thereof is omitted.
[0067]
As shown in FIG. 4A, an EB resist (manufactured by Tokyo Ohka Kogyo Co., Ltd .: EP-002) 430 is formed on a light-shielding film Cr film 420 formed on a transparent substrate 410 made of quartz or the like by the above-described embodiment. According to the method of mode 2, application is performed with a resist film thickness of 3000 °. Thereafter, as shown in FIG. 4B, EB drawing, baking and development are performed. The EB lithography is performed by using an EB lithography apparatus with an acceleration voltage of 50 kV manufactured by Toshiba Machine Co., followed by baking at 100 ° C. for 15 minutes, and after cooling, a developer NMD-3 manufactured by Tokyo Ohka Kogyo Co., Ltd. (2.38%), spin-dry after development for 60 seconds to form a desired resist pattern 435 on the light-shielding Cr film 420.
[0068]
Further, using the EB resist pattern 435 as a mask, the light-shielding film Cr film 420 is dry-etched in a chlorine gas and oxygen gas atmosphere for 10 minutes (total gas flow rate 200 sccm (chlorine gas 160 sccm, oxygen gas 40 sccm), pressure 0.68 Pa). By doing so, a light-shielding film Cr film pattern 425 can be obtained as shown in FIG.
[0069]
Thereafter, as shown in FIG. 4D, the EB resist pattern 435 is peeled off, and the transparent substrate 410 is washed and dried, so that a light-shielding film Cr film pattern 425 can be obtained on the transparent substrate 410.
[0070]
The in-plane dimensional variation of the light-shielding film Cr film pattern 425 on the transparent substrate 410 manufactured as described above was measured at 169 points (13 points) with a 0.5 μm line and space pattern in a 6-inch mask substrate area (132 mm × 132 mm area). (× 13 points) As a result of the measurement, the dimensional variation in the light-shielding film Cr film pattern 425 was 13 nm (3σ value), and a sufficient value was obtained as the dimensional uniformity required for the next generation mask.
[0071]
In the above-described fourth embodiment, the Cr film 420 is used as the light-shielding film. However, the light-shielding film is not limited to the Cr film 420, and other materials such as AlSi, MoSi, WSi, TiSi, NiSi, and ZrSi are used. The same effect can be obtained by using a metal film such as Cr, CrF or the like or a mixture thereof. As the transparent substrate (mask) 410, the gas used in the dry etching is applied to a MoSiON film, a MoSiN film, a ZrSiO film, a CrF film, a CrFO film, a TaSiO film, and a TiSiON film which are halftone phase shift films.₄And O₂By using a mixed gas of (100 sccm: 5 sccm), the same can be applied. Although a 6-inch mask substrate is used in the fourth embodiment, the present invention can be similarly applied to a 230-mm mask substrate, which is a next-generation mask substrate.
[0072]
In the above-described fourth embodiment, EP-002 manufactured by Tokyo Ohka Kogyo Co., Ltd. was used as the EB resist. However, the EB resist is not limited to this, and other EB resists (for example, ZFP7000 which is an organic developing resist) (Manufactured by ZEON Corporation) or a resist for excimer laser for KrF or ArF used in the photolithography process can be used.
[0073]
As described above, according to the fourth embodiment, by using the resist coating apparatus described in the first embodiment and the resist coating method described in the second or third embodiment, the transparent substrate 410 made of quartz or the like is used. A light-shielding film Cr film having a dimension variation of 13 nm (3σ value) as a result of measuring 169 points (13 points × 13 points) with a 0.5 μm line and space pattern in a 6-inch mask substrate area (132 mm × 132 mm area) A pattern 425 can be obtained.
[0074]
Embodiment 5 FIG.
Next, a rotating cup type resist coating apparatus according to a fifth embodiment will be described. FIG. 5 is a sectional view illustrating a configuration of a resist coating apparatus according to the fifth embodiment. FIG. 6 is a plan view showing the resist coating apparatus according to the fifth embodiment as viewed from the direction of arrows II-II shown in FIG.
[0075]
The resist coating apparatus according to the fifth embodiment includes a rotating cup 10. The rotating cup 10 is a columnar member whose upper part is open. In the vicinity of the bottom surface of the rotating cup 10, an exhaust port 12 communicating with the internal space is provided. Here, the internal space of the rotating cup 10 means a space formed by the rotating cup 10 and an upper lid 28 described later. At the end of the exhaust port 12, a check valve 14 that allows only the flow of the fluid from the inside of the rotating cup 10 to the outside is provided. The check valve 14 is made of, for example, a combination of metal and rubber. The structure of the check valve 14 is not limited to this, and may be any structure as long as it can prevent the backflow of air.
[0076]
The rotating cup 10 can hold the rectangular mask substrate 16 therein, and can rotate around the central axis while holding the mask substrate 16. In the fifth embodiment, a 6025 substrate having a size of 6 inches square and a thickness of 0.25 inches is used as the mask substrate 16.
[0077]
The resist coating apparatus according to the fifth embodiment includes a resist dropping unit 18 on the opening side of the rotating cup 10. By moving the arm, the resist dropping unit 18 can realize a state where the resist can be applied to the inside of the rotating cup 10 and a state where the resist does not overlap with the rotating cup 10. Hereinafter, those states are referred to as a “dropping state” and a “non-dropping state”, respectively.
[0078]
The resist coating apparatus according to the fifth embodiment further includes a multilayer filter 20 that can fit into the opening of the rotating cup 10 when the resist dropping unit 18 is in a non-dropping state.
[0079]
FIG. 7 is a diagram illustrating the multilayer structure filter 20 in a plan view. As shown in FIG. 7, the multilayer filter 20 includes a peripheral filter 22 that covers the entire surface of the opening of the rotating cup 10, a filter that is smaller than the peripheral filter 22, and that is located at the center of the peripheral filter 22. And a central filter 24 arranged.
[0080]
The peripheral filter 22 and the central filter 24 can secure sufficient rigidity even if they are thin and lightweight, have uniform fine holes, and are made of a material with low dusting properties. Is preferred. In the fifth embodiment, in consideration of the above points, the peripheral filter 22 and the central filter 24 are formed of porous glass having micropores on the order of microns (2 mm in thickness). Alternatively, the filter can be made of a ceramic material. Since the multilayer structure filter 20 has the above-described multilayer structure, it has a dense filter structure in the center and a sparse filter structure in the periphery.
[0081]
An upper lid 28 is provided above the multilayer structure filter 20 via an O-ring 26. The upper lid 28 can close the opening of the rotating cup 10 from above the multilayer filter 20 when the resist dropping unit 18 is in a non-dropping state. As a result, the internal space of the rotating cup 10 has a space (first space) including the mask substrate 16 divided by the multilayer filter 20. The upper cover 28 is provided with a leak valve 30. The leak valve 30 is a valve mechanism that closes a space surrounded by the O-ring 26, that is, a vent that connects the upper space of the multilayer structure filter 20 and the upper space of the upper cover 28, and is opened or closed manually or by an actuator. Can be done. As described above, the internal space of the rotating cup 10 has a space (second space) on the side that does not include the mask substrate 16 and is separated by the multilayer filter 20.
[0082]
The above-mentioned multilayer structure filter 20 and the upper lid portion 28 are rotated around the central axis of the rotating cup 10 together with the rotating cup 10 and the mask substrate 16 held therein while being fixed on the upper portion of the rotating cup 10. be able to.
[0083]
Next, a method of applying a resist to the mask substrate 16 using the resist applying apparatus according to the fifth embodiment will be described with reference to FIGS.
As shown in FIG. 9A, in the step of forming a resist film, first, a rectangular mask substrate 16 is disposed on a columnar rotating cup 10. Next, the resist coating unit 18 is dropped, and a predetermined amount of the resist 32 is coated near the center of the mask substrate 16. In the fifth embodiment, EB resist EP-002 (manufactured by Tokyo Ohka Kogyo Co., Ltd .: resist viscosity 3.5 cp) was used as the resist 32.
[0084]
After the resist coating unit 18 is set to the non-dropping state, the multilayer structure filter 20 and the top cover 28 are set in the opening of the rotating unit 10, and then the rotation of the rotating cup 10 is started. The rotation of the rotating cup 10 is controlled according to the sequence shown in FIG. Specifically, after the rotation starts, the rotation speed of the rotating cup 10 is accelerated to a predetermined rotation speed (2500 rpm) at an applied acceleration (10,000 rpm / sec), and is increased to the predetermined rotation speed (3 seconds). Will be maintained. Thereafter, the rotary cup 10 is decelerated continuously at a predetermined deceleration (-200 rpm / sec) for a predetermined period (12.5 seconds), so that the rotating cup 10 is brought into a stopped state (a state where the rotational speed is 0 rpm).
[0085]
FIG. 9B shows a state when the rotating cup 10 is accelerated. When the rotating cup 10 is accelerated, the resist 32 spreads due to centrifugal force, and a film having a substantially uniform thickness is formed on the surface of the mask substrate 16. At this time, the air inside the rotating cup 10 is discharged to the outside of the rotating cup 10 through the check valve 14 together with the extra resist 32. As a result, the internal pressure of the rotating cup 10 becomes lower than the atmospheric pressure.
[0086]
When the mask substrate 16 rotates inside the rotating cup 10 as in the fifth embodiment, large friction (friction with air) occurs near the four corners of the mask substrate 16 even though the mask substrate 16 is rectangular. Can be prevented. Therefore, when the rotating cup 10 is accelerated and rotated at a constant speed, the thickness of the resist 32 applied on the mask substrate 16 is made substantially uniform over the entire pattern forming region (for example, a 132 mm × 132 mm square region). be able to.
[0087]
FIG. 9B shows a state when the rotating cup 10 is decelerated. When the rotating cup 10 starts to decelerate, air tends to flow backward from the outside of the rotating cup 10 toward the inside thereof due to a pressure difference between the inside and outside of the rotating cup 10. When such a backflow of air occurs in the exhaust port 12, the resist 32 accumulated at the end of the mask substrate 16 is blown off toward the center, and a portion having an uneven resist film thickness is formed in the pattern formation region. May be formed. The device according to the fifth embodiment includes the check valve 14 at the exhaust port 12, so that such backflow of air can be reliably prevented. Therefore, according to the apparatus of the fifth embodiment, as shown in FIG. 9B, even when the rotation cup 10 is decelerated, the thickness of the resist 32 is substantially reduced over the entire pattern formation region of the mask substrate 16. It can be kept uniform.
[0088]
FIG. 9C shows a state after the rotation of the rotating cup 10 is stopped. Immediately after the rotation of the rotating cup 10 stops, the solvent contained in the resist 32 occupies a high partial pressure in the internal space of the rotating cup 10. Therefore, in order to dry the resist 32, it is necessary to introduce air into the rotating cup 10.
[0089]
After the rotation cup 10 stops, for example, when the multilayer structure filter 20 and the upper lid 28 are removed from the rotation cup 10, the atmosphere can be introduced into the internal space of the rotation cup 10. However, when air is rapidly introduced into the inside of the rotating cup 10 by such a method, the resist 32 dries rapidly, and the film thickness tends to vary due to drying unevenness.
[0090]
As described above, in the fifth embodiment, after the rotation cup 10 stops, the leak valve 30 is opened as shown in FIG. Atmosphere is introduced into the space. In this case, since the introduction speed of the atmosphere becomes slow, the resist 32 can be dried slowly, and variation in the resist film thickness due to uneven drying can be effectively prevented.
[0091]
During the rotation of the rotating cup 10, the resist 32 easily accumulates on the peripheral portion of the mask substrate 16. After the rotation of the rotating cup 10 stops, the resist 32 accumulated on the peripheral edge of the mask substrate 16 tends to spread toward the center of the mask substrate 16 due to its fluidity. Therefore, in order to make the thickness of the resist 32 uniform over the entire pattern formation region of the mask substrate 16, the resist 32 remaining on the peripheral portion of the mask substrate 10 is quickly removed after the rotation of the rotating cup 10 is stopped. It is desirable to dry.
[0092]
In the fifth embodiment, the multi-layer structure filter 20 has a dense filter structure in the central portion and a sparse filter structure in the peripheral portion as described above. According to such a filter structure, after the leak valve 30 is opened and the air is introduced into the upper layer of the multilayer structure filter 20, a larger amount of fluid is provided near the periphery of the rotary cup 10 than near the center thereof. Air is introduced. Therefore, according to the apparatus of the fifth embodiment, the resist 32 present on the peripheral portion of the mask substrate 16 can be quickly dried, and the resist film having a uniform thickness can be formed over the entire pattern formation region of the mask substrate 16. Can be formed.
[0093]
In the fifth embodiment, the above-described drying of the resist 32 is performed while rotating the rotating cup 10 at a rotation speed of 20 rpm. After the resist 32 is dried, a baking process is performed at 80 ° C. for 15 minutes, and then a cooling process of exposing the mask substrate 16 to an atmosphere at 23 ° C. for 5 minutes is performed. The above-described series of processing is executed with the target value of the coating thickness of the resist 32 set to 3,000 angstroms.
[0094]
Next, with reference to FIG. 10 and FIG. 11, the effect of the check valve 14 provided in the resist coating apparatus of the fifth embodiment will be described.
[0095]
FIGS. 10A and 10B show the measurement results showing the uniformity of the resist film thickness when the resist 32 is applied according to the above-described conditions in a state where the check valve 14 is not attached to the exhaust port 12. Show. More specifically, the measurement results of the resist film thickness at 121 points in a 132 mm × 132 mm square area used as a pattern formation area are shown.
[0096]
FIGS. 11A and 11B show the uniformity of the resist film thickness when the resist 32 is applied by the apparatus according to the fifth embodiment, that is, when the check valve 14 is attached to the exhaust port 12. The measurement results showing the properties are shown. The result shown in FIG. 11 also shows the measurement result of the resist film thickness at 121 points in a 132 mm × 132 mm square region used as a pattern formation region, similarly to the result shown in FIG.
[0097]
Table 1 shows a comparison between the result shown in FIG. 10 and the result shown in FIG.
[0098]
[Table 1]

[0099]
As shown in Table 1, when the check valve is not attached to the exhaust port 12 (in the case of FIG. 10), the average value of the resist film thickness is 3064.2 Å, and the range within the range of 80 mm × 80 mm is The range within the range of 22.6 Å and 132 mm × 132 mm was 36.0 Å. On the other hand, in the case of the fifth embodiment (in the case of FIG. 11), the average value of the resist film thickness is 3066.1 angstroms, and the range within a range of 80 mm × 80 mm is 12.6 angstroms and 132 mm × 132 mm. The range within the range was 13.4 angstroms.
[0100]
From the above results, it was confirmed that when the check valve 14 was attached to the exhaust port 12, the coating uniformity of the resist was improved both within the range of 80 mm × 80 mm and within the range of 132 mm × 132 mm. As described above, when the backflow of the air is prevented by the check valve 14, the uniformity of the resist film thickness can be significantly improved.
[0101]
Next, a method of forming a mask pattern on the mask substrate 16 will be described with reference to FIG.
[0102]
FIG. 12A shows a state after the resist 32 (made by Tokyo Ohka Kogyo Co., Ltd .: EP-002) is applied with a thickness of 3000 Å on the rectangular mask substrate 16 by the above procedure. Hereinafter, it is assumed that the mask substrate 32 has a laminated structure of a transparent substrate 34 made of quartz or the like and a light shielding film 36 made of Cr or the like, as shown in FIG.
[0103]
As shown in FIG. 12B, the resist 32 is patterned into a desired shape by being subjected to EB drawing, baking, and developing processes. The EB drawing of the resist 32 was performed using a 50 kV accelerating voltage drawing device manufactured by Toshiba Machine Co., Ltd. The baking process is performed at 100 ° C. for 8 minutes. After the mask substrate 16 is cooled to 23 ° C., the developing process is performed for 60 seconds using a developing solution NMD-3 (2.38%) manufactured by Tokyo Ohka Kogyo. When the development processing is completed, spin drying for drying the mask substrate 16 is performed.
[0104]
As shown in FIG. 12C, dry etching of the light shielding film 36 is performed using the patterned resist 32 as a mask. The etching of the light-shielding film 36 is performed in an atmosphere of chlorine gas and oxygen gas under the following conditions. As a result, the light shielding film 36 is patterned similarly to the resist 32.
・ Bias voltage: 20W
・ Antenna power: 0.5kW
・ Total gas flow rate 100sccm (chlorine gas 80sccm, oxygen gas 20sccm)
・ Pressure 0.68Pa
・ Etching time: 720 sec
[0105]
As shown in FIG. 12D, the resist 32 is peeled from the upper part of the light shielding film 36. Next, the mask substrate 16 having a desired mask pattern is formed by performing cleaning and drying of the mask substrate 16.
[0106]
The in-plane dimensional variation of the mask pattern thus manufactured was measured by the following procedure. That is, 169 points (13 points × 13 points) of a 2 μm cross pattern are formed in the pattern forming area (132 mm × 132 mm) of the 6025 substrate. Next, the dimensional accuracy of the cross pattern is measured using a Nikon lightwave interferometer XY-6i. As a result, the variation value of the pattern dimension on the mask substrate 16 was 12 nm (3σ value) in both the X and Y directions. This value is a value sufficient as the dimensional accuracy required for the next-generation mask. As described above, according to the mask pattern forming method of the fifth embodiment, since the thickness of the resist is uniform, extremely excellent pattern dimensional accuracy can be realized.
[0107]
By the way, in the above embodiment, the light shielding film 36 provided in the mask substrate 16 is formed of Cr, but the material of the light shielding film 36 is not limited to this. More specifically, the light-shielding film 36 may be formed using a metal film such as AlSi, MoSi, WSi, TiSi, NiSi, ZrSi, or a mixture thereof.
[0108]
In addition, the present invention provides an etching gas of CF₄/ O₂Or SF₆/ O₂For example, it can be applied to a halftone phase shift film such as MoSiON, MoSiN, ZrSiO film, CrF film, CrFO film, TaSiO film, and TiSiON film.
[0109]
In the above embodiment, a 6-inch mask substrate (6025 substrate) is used. However, the present invention relates to a next-generation mask substrate, that is, a side length of 230 mm and a thickness of 9 mm. The present invention can also be applied to a mask substrate having
[0110]
Further, in the above embodiment, the rectangular substrate on which the resist 32 is applied is limited to the mask substrate 16, but the application of the present invention is not limited to this. That is, the resist coating method of the present invention may be applied when a desired pattern is formed on a rectangular liquid crystal substrate for a liquid crystal display, particularly a large liquid crystal substrate. In this case, the uniformity of the resist film thickness at the periphery of the liquid crystal substrate can be improved.
[0111]
Further, in the above embodiment, the substrate on which the resist 32 is applied is limited to the rectangular mask substrate 16, but the application of the present invention is not limited to this, and an 8 inch wafer or a 300 mm wafer may be used. The present invention may be applied to a circular substrate. In this case, it is possible to improve the uniformity of the film thickness distribution in the peripheral portion of those wafers.
[0112]
In the above embodiment, EP-002 manufactured by Tokyo Ohka Kogyo Co., Ltd. was used as the resist 32. However, the resist 32 is not limited to this, and is used for other EB resists or excimer lasers for KrF or ArF. A resist may be used.
[0113]
Further, in the above embodiment, the resist is applied on the substrate. However, the application of the present invention is not limited to the resist. When applying SOG (Spin On Glass) or the like to the substrate, The coating method of the present invention may be used.
[0114]
Embodiment 6 FIG.
FIGS. 13A to 13F and FIGS. 14A to 14D show steps of an HT film forming method according to the sixth embodiment of the present invention. In FIGS. 13A to 13F and FIGS. 14A to 14D, parts denoted by the same reference numerals as those in FIG. 4 (Embodiment 4) indicate the same elements, and thus description thereof is omitted. The sixth embodiment is a method for forming an HT film pattern. A description of the same steps as those in Embodiment 4 is omitted. As the film structure of the sixth embodiment, as shown in FIGS.
(1) Resist 430 / Cr420 / HT415 / substrate (Qz) 410
And as shown in FIGS. 14 (A) to (D),
(2) Resist 430 / HT415 / substrate (Qz) 410
There are two. Here, the substrate Qz is a transparent substrate or the like.
[0115]
In the case of (1), as shown in FIGS. 13A to 13F, after patterning the resist 430, the Cr 420 is patterned using the pattern 435 as a mask, and then the HT film 415 is patterned with the Cr pattern 425. Etch as a mask. The meaning of the Cr pattern 425 is to form a light shielding frame of the mask. The light shielding frame is around the pattern area 413.
[0116]
As shown in FIG. 13 (F), the resist is again applied and drawn to remove the resist in portions other than the frame, and then the Cr is removed by wet etching or the like.
[0117]
In the case of (2), as shown in FIGS. 14A to 14D, after patterning the resist 430, the HT 415 is etched using the pattern 435 as a mask. At this time, a light shielding portion is formed as a dot pattern using the HT film 415 outside the pattern region 413. The fine dot pattern is 0.3 μm or less. As shown in FIG. 14D, the HT 415 has the advantage of requiring only a single layer.
[0118]
The Cr etching of (1) is the same condition as the Cr film etching of the fourth embodiment. The HT etching is performed using NLDE-9035 (manufactured by ULVAC, Inc.) at a pressure of 0.68 Pa and a gas CF.₄/ O₂= 100 sccm: 5 sccm for 350 sec. As for the uniformity, since Cr is transferred as it is, it is formed with approximately the same accuracy and 13 nm (30).
[0119]
【The invention's effect】
As described above, according to the resist coating method, the resist coating apparatus, and the mask pattern forming method using the resist coating method of the present invention, two central filters and a peripheral filter made of the same material are overlapped. By using this, the filter density in the peripheral filter can be made lower than the filter density in the central filter, so that the resist drying speed at the four sides of the rectangular substrate can be increased. As a result, a resist coating method, a resist coating apparatus, and a resist that can increase the efficiency in mask coating throughput and perform high-precision resist coating with a reduced difference in resist thickness around the four sides of a rectangular substrate A method for forming a mask pattern using a coating method can be provided.
[0120]
Furthermore, according to the present invention, a resist coating method and a resist coating apparatus that can reduce the deflection of the center portion due to the weight of the filter itself even when the mask pattern region is enlarged by using a rectangular filter. And a method of forming a mask pattern using a resist coating method.
[0121]
Further, since the present invention is configured as described above, it has the following effects.
[0122]
BookAccording to the invention, it is possible to prevent the backflow of air from occurring at the outlet of the rotating cup. Therefore, according to the present invention, after the rotating cup starts rotating, the resist accumulated at the end of the substrate is not blown off toward the center by the air flowing backward from the exhaust port. Therefore, according to the present invention, the resist can be applied with a uniform film thickness on the central portion of the substrate, more specifically, on the entire region of the pattern forming region of the substrate.
[0123]
BookAccording to the invention, it is possible to introduce a pressure equal to or higher than the atmospheric pressure into the first space including the substrate via the filter. In this case, since the flow of air into the first space becomes gentle, the resist applied to the substrate surface can be dried slowly. Therefore, according to the present invention, it is possible to form a resist film having a uniform film thickness by preventing variations in the resist film thickness due to drying unevenness.
[0124]
BookAccording to the invention, the atmospheric pressure can be easily introduced into the second space only by opening the leak valve. Therefore, according to the present invention, the resist can be dried slowly with a simple operation.
[0125]
BookAccording to the present invention, a resist film having a uniform thickness can be formed on the surface of a mask substrate, that is, on the surface of a light-shielding film. Therefore, according to the present invention, the resist film and the light-shielding film can be patterned with high precision, and a highly accurate mask pattern can be formed.
[0126]
BookAccording to the present invention, a resist film having a uniform thickness can be formed on the surface of a rectangular liquid crystal substrate. For this reason, according to the present invention, the resist film can be patterned with high precision, and a desired pattern can be accurately formed on the liquid crystal substrate.
[Brief description of the drawings]
FIG. 1 is a diagram showing a resist coating device according to a first embodiment of the present invention.
FIG. 2 is a diagram illustrating an example of a shape of a filter 140 used in the first embodiment of the present invention.
FIG. 3 is a diagram showing a resist coating method according to a second embodiment of the present invention.
FIG. 4 is a diagram showing steps of a mask pattern forming method according to a fourth embodiment of the present invention.
FIG. 5 is a diagram illustrating a configuration of a resist coating apparatus according to a fifth embodiment of the present invention.
FIG. 6 is a view showing the resist coating apparatus according to the fifth embodiment of the present invention as viewed from the direction of arrows II-II shown in FIG.
FIG. 7 is a plan view of a multilayer filter provided in a resist coating apparatus according to a fifth embodiment of the present invention.
FIG. 8 is a diagram for explaining an operation of the resist coating apparatus according to the fifth embodiment of the present invention.
FIG. 9 is a diagram for explaining a resist coating procedure by the resist coating apparatus according to the fifth embodiment of the present invention.
FIG. 10 is a measurement result showing the uniformity of a resist film obtained when a check valve is not attached to an exhaust port.
FIG. 11 is a measurement result showing uniformity of a resist film formed by the resist coating apparatus according to the fifth embodiment of the present invention.
FIG. 12 is a diagram illustrating a procedure for forming a mask pattern on a mask substrate.
FIG. 13 is a diagram showing a step of an HT film forming method according to a sixth embodiment of the present invention.
FIG. 14 is a diagram showing a step of an HT film forming method according to a sixth embodiment of the present invention.
FIG. 15 is a diagram showing an outline of a conventional method of controlling a resist drying speed using a metal sintered body.
FIG. 16 is a view showing a conventional sintered metal filter having a circular shape.
FIG. 17 is a view for explaining a resist coating procedure using a conventional resist coating apparatus.
[Explanation of symbols]
Reference Signs List 10 rotating cup, 12 exhaust port, 14 check valve, 16 mask substrate, 18 resist coating unit, 20 multilayer structure filter, 22, 320 peripheral filter, 24 central filter, 28 top cover, 30 leak valve, 32, 500 resist, 34,410 transparent substrate, 36 light-shielding film, 100 resist waste liquid and organic matter exhaust unit, 110,510 rectangular substrate, 120 rotating cup unit, 130 resist dropping unit, 140 filter, 150 upper rotating cup, 310 central filter, 413 pattern region, 415 HT film, 420 light shielding film Cr film, 430 EB resist film, 425 light shielding film Cr film pattern, 435 EB resist pattern, 520 mask pattern region, 610 metal sintered body pore filter .

Claims (12)

A step of introducing a rectangular substrate into a column-shaped container part having an open top,
A step of supplying a resist dropwise onto the rectangular substrate introduced into the container section,
A step of covering the opened upper part of the container part with a rectangular filter part,
A step of covering the container part with a cover part that can be opened and closed via the filter part,
A step in which the lid closes the container through the filter;
An application step of rotating the rectangular substrate, the filter unit and the lid together with the container around an axis in a column direction of the columnar container, and applying a resist dropped and supplied on the rectangular substrate; ,
A drying step of drying the resist applied on the rectangular substrate by opening only the lid while the filter unit covers the open top of the container unit ,
The rectangular substrate is any one selected from the group consisting of a light shielding film made of a MoSi (molybdenum silicide) film formed on a quartz substrate or a MoSiON film, a CrF ₂ film, a TaSiO film, a ZrSiO film, a CrFO film, and a MoSiN film. Has a translucent film of
In the dropping step, after the resist dropping unit drops a resist for an electron beam onto a light-shielding film or a semi-transparent film formed on the quartz substrate, the transparent substrate, the filter unit, and the lid unit are formed into the columnar shape. A resist coating method comprising: rotating the container together with the container around an axis in a column direction of the container . A rectangular substrate;
An upper part is opened, a column-shaped container part in which the rectangular substrate is introduced,
A resist dropping section for dropping a resist onto the rectangular substrate introduced into the container section,
A rectangular filter portion that covers the open top of the container portion,
A lid portion that covers the container portion so that it can be opened and closed via the filter portion,
A gas introduction unit for introducing a gas higher in temperature than the gas introduced into the resist at the center of the rectangular substrate, from only the periphery of the filter unit to the resist on the periphery of the rectangular substrate,
When applying the resist on the rectangular substrate, after the resist is dropped from the resist dropping portion onto the rectangular substrate introduced into the container portion and supplied, the lid portion is connected to the container portion via the filter portion. In a closed state, the rectangular substrate, the filter unit and the lid unit are rotated together with the container unit around an axis in the column direction of the columnar container unit, and the resist supplied dropwise on the rectangular substrate is supplied. Apply,
When drying the resist applied on the rectangular substrate, only the lid is opened with the filter covering the open top of the container . A rectangular substrate;
An upper part is opened, a column-shaped container part in which the rectangular substrate is introduced,
A resist dropping section for dropping a resist onto the rectangular substrate introduced into the container section,
A rectangular filter portion that covers the open top of the container portion,
A lid portion that opens and closes the container portion via the filter portion;
With
The filter unit, the filter density of the peripheral part is less than the filter density of the central part,
When applying the resist on the rectangular substrate, after the resist is dropped from the resist dropping portion onto the rectangular substrate introduced into the container portion and supplied, the lid portion is connected to the container portion via the filter portion. In a closed state, the rectangular substrate, the filter unit and the lid unit are rotated together with the container unit around an axis in the column direction of the columnar container unit, and the resist supplied dropwise on the rectangular substrate is supplied. Apply,
When drying the resist applied on the rectangular substrate, only the lid is opened with the filter covering the open top of the container . A rectangular substrate;
An upper part is opened, a column-shaped container part in which the rectangular substrate is introduced,
A resist dropping section for dropping a resist onto the rectangular substrate introduced into the container section,
A rectangular filter portion that covers the open top of the container portion,
A lid portion that opens and closes the container portion via the filter portion,
The filter unit has a rectangular shape similar to the shape of the rectangular substrate, is installed in a state where the four sides of the filter unit and the four sides of the rectangular substrate coincide,
When applying the resist on the rectangular substrate, after the resist is dropped from the resist dropping portion onto the rectangular substrate introduced into the container portion and supplied, the lid portion is connected to the container portion via the filter portion. In a closed state, the rectangular substrate, the filter unit and the lid unit are rotated together with the container unit around the axis in the column direction of the columnar container unit, and the resist supplied dropwise on the rectangular substrate is supplied. Apply,
When drying the resist applied on the rectangular substrate, only the lid is opened with the filter covering the open top of the container. The resist coating apparatus according to claim 3, further comprising a rectangular support portion that supports an edge portion of the filter portion. A gas introduction unit that introduces a gas higher in temperature than the gas introduced into the resist at the center of the rectangular substrate from only the periphery of the filter unit to the resist on the periphery of the rectangular substrate, The resist coating apparatus according to any one of claims 3 to 5 . The resist coating device according to claim 2, wherein the filter unit is formed using an aluminum sintered body . The resist coating apparatus according to claim 2, wherein the filter unit is formed using a porous glass or a ceramic material . A resist coating method for coating a resist on a surface of a substrate,
Holding the substrate in a hollow rotating cup rotatable about a central axis,
Applying a resist on the surface of the substrate held in the rotating cup,
The rotating cup, closing the opening provided for loading and unloading the substrate with a lid,
In a state in which the rotation cup is provided with a discharge port provided for discharging extra resist from the internal space to the external space, a check valve that allows only the flow of fluid from the inside of the rotation cup to the outside is mounted. Rotating the lid that closes the opening and the substrate held therein, together with the rotating cup;
After the rotation of the rotating cup is stopped, removing the substrate from the inside thereof,
The internal space of the rotating cup is partitioned into a first space including the substrate by a filter and a second space not including the substrate, and
After the rotation of the rotating cup has been sufficiently decelerated, introducing a pressure higher than the atmospheric pressure into the second space,
The rotary cup or the lid portion is provided with a vent, a leak valve for opening and closing the vent,
The step of introducing a pressure equal to or higher than the atmospheric pressure into the second space includes the step of opening the leak valve . 10. The method according to claim 9, wherein the filter is made of a porous glass or a ceramic material . A method for forming a mask pattern of an exposure mask used in a semiconductor manufacturing process,
Applying a resist by a resist coating method according to claim 9 or 10 on a mask substrate having a light-shielding film or a translucent film on the surface of a transparent substrate;
Patterning the resist into a desired pattern;
Using the patterned resist as a mask, etching the light-shielding film or translucent film,
A method of forming a mask pattern, comprising: A method for forming a desired pattern on a rectangular liquid crystal substrate,
Applying a resist on the liquid crystal substrate by the resist application method according to claim 9 or 10,
Patterning the resist into a desired pattern;
Patterning a desired pattern on the liquid crystal substrate using the patterned resist as a mask,
A pattern forming method for a liquid crystal substrate, comprising:

Images