JP4726173B2

JP4726173B2 - Liquid crystal matrix projection exposure apparatus and liquid crystal matrix projection exposure method

Info

Publication number: JP4726173B2
Application number: JP2001295060A
Authority: JP
Inventors: 敏行堀内
Original assignee: Tokyo Denki University
Current assignee: Tokyo Denki University
Priority date: 2001-08-23
Filing date: 2001-08-23
Publication date: 2011-07-20
Anticipated expiration: 2021-08-23
Also published as: JP2003068634A

Description

【０００１】
【発明の属する産業分野】
本発明は半導体集積回路、光エレクトロニクス素子、マイクロマシン部品等の微細パタンを半導体ウエハ等の被露光基板上に転写する装置および方法に関するものである。
【０００２】
【従来の技術】
従来、半導体集積回路、光エレクトロニクス素子、マイクロマシン部品等の微細パタンを、半導体ウエハ、金属基板、ガラス基板等の各種基板上に形成するのに、投影露光装置および投影露光方法が多用されている。
【０００３】
図１６は従来の投影露光装置の構成図である。この従来の投影露光装置を用いて投影露光を行うには、合成石英、ガラス等の光透過基板上にクロム等の遮光体で原図となるパタンを形成したレチクルや、シリコンウエハ等の枠上に設けた各種薄膜や薄い金属板板等に原図となるパタン形状の穴を開けたステンシルマスクを原図基板８３として用いる。
【０００４】
そして、前記原図基板８３に光源と照明光学系によって構成された照明装置３によって照明光４を当て、投影レンズ、投影ミラー光学系、レンズとミラーとを適宜組み合わせた光学系等の投影光学系５を用いて、該原図基板８３上のパタンを被露光基板６の上に投影する。
【０００５】
該被露光基板６、たとえば半導体ウエハ、金属基板、ガラス基板等の上には、予めレジスト等の感光性材料７を塗布や吹き付け等により付加しておく。すると、前記原図基板８３に当てた照明光線４により前記感光性材料７が該原図基板８３の透過部の形状に対応したパタン形状に感光する。
【０００６】
したがって、露光後、現像を行うと、前記感光性材料７がポジ形かネガ形かに応じて感光部または未感光部の感光性材料７が除去され、前記原図基板８３上のパタン形状が該被露光基板６上に転写される。
【０００７】
このように、従来の投影露光装置および投影露光方法は、レチクルやステンシルマスク等の原図基板８３上のパタンを被露光基板６上の感光性材料に転写する装置および方法であるので、まずは所望のパタンに対応したパタンを有する原図基板８３が必要不可欠であった。
【０００８】
原図基板８３は、形成してある微細パタンに少しでも間違いや欠陥があると、転写したパタンを使用した製品の全てが不良品となってしまうことから、検査、確認が重要であり、非常に高価である。パタンは形状だけでなく、線幅や穴の大きさ、さらにはそれらの位置等の各種精度も問題となるため、パタンが微細になるととくに高価となる。
【０００９】
一方、社会の消費傾向の多様化に伴い、製品は多品種少量生産化する傾向にある。たとえば、半導体集積回路製品では、特定用途向けＩＣが伸びる一方、極めて大量に同じ製品を生産する例はメモリ等極一部に限られている。
【００１０】
そして、まだ汎用品が多数出回るに至っていないマイクロマシンの部品等は、当初から半導体集積回路製品と比べると桁違いに少量しか生産しないのが通例である。
【００１１】
ところが、生産量の多少に拘らず、投影露光を行う限りは元になるパタンを有する原図基板８３を必要とするので、少量生産品では原図基板８３の価格が製品価格に大きく影響するようになる。
【００１２】
また、原図基板８３上のパタンの変更、修正は特別な場合を除いてほとんど不可能に近く、製品毎、パタンの変更毎に原図基板８３を作り直す必要がある。
【００１３】
このため、最近になって、製品毎、パタンの変更毎に従来の原図基板８３を作り直すのではなく、液晶パネルの各液晶セルを透過、遮光を制御するマトリックススイッチとして利用して原図基板８３の代替となし、透過部、遮光部を所定の配置で指定して投影露光を行う、図１７に示す液晶マトリックス投影露光装置およびそれを利用した露光方法の有用性がたとえば、第４６回応用物理学関係連合講演会講演予稿集７４２ページ（１９９９）やＪａｐａｎｅｓｅＪｏｕｒｎａｌｏｆＡｐｐｌｉｅｄＰｈｙｓｉｃｓＶｏｌ．３８，ｐｐ．３２４−３２９（２０００）に開示されている。
【００１４】
上記の液晶マトリックス投影露光装置および液晶マトリックス投影露光方法によれば、液晶パネル１の各セルの透過、遮光をパタン指定部８からキーボード操作等により容易に指定できる。９は液晶パネル１とパタン指定部８とがケーブル等で連結されていることを示す。
【００１５】
したがって、従来のレチクルやステンシルマスク等固定のパタンを有する原図基板８３は不要である。
【００１６】
また、パタンの設計データをパーソナルコンピュータ等によって、液晶パネル１の各セルへの制御指令に自動的に変換することが容易にできるため、液晶パネル１の各セルの透過、不透過の制御を自動的におこなうことも可能である。
【００１７】
なおかつ、パタンの設計データをパーソナルコンピュータ等によって、液晶パネル１の各セルへの制御指令に自動的に変換するようにすれば、該設計データを用いてパタンの検査ができるので、間違いや欠陥を大幅に削減することができ、パタンの変更や修正も極めて容易にできる。
【００１８】
【発明が解決しようとする課題】
しかしながら、図１７に示した開示された液晶マトリックス投影露光装置および液晶マトリックス投影露光方法には、以下に示すような問題があった。
【００１９】
図１８は液晶パネル１の模式図である。図１８（ａ）に示すように、液晶パネル１の各液晶セル１０の間に境界部８４があり、該境界部８４の部分はセル部の透過、遮光の指定と関係なく、常に不透過となってしまった。
【００２０】
また、単純マトリックス方式の液晶パネル１の場合には、液晶セル１０の中には障害物が存在しないが、アクティブマトリックス方式の液晶パネル１の場合には、図１８（ｂ）に示すように、液晶セル１０の中に薄膜トランジスタ（ＴＦＴ）１９が形成されており、該ＴＦＴ１９の部分が前記境界部８４に加えて常に不透過となってしまった。
【００２１】
図１９は従来の液晶マトリックス投影露光装置によって形成したパタン形状の説明図である。単純マトリックス方式の液晶パネル１を用いる場合でも、遮光液晶セル８５の中に連続した透過液晶セル８６を並べて線状の感光部を形成しようとしても、境界部８４に対応する部分の露光量が少ないので、転写パタンにくびれや突起ができてしまった。
【００２２】
たとえば、図１９（ａ）に示すように、液晶パネル１の斜線部を遮光液晶セル８５、白枠部を透過セル８６に指定して投影露光を行うと、本来直線上のパタンが必要なのに、感光性材料７としてネガ形レジストを用いた場合には図１９（ｂ）に示すようなレジストパタン８７となってしまい、転写パタンにくびれ８８が生じてしまった。また、感光性材料７としてポジ形レジストを用いた場合には図１９（ｃ）に示すようなレジストパタン８９となってしまい、転写パタンに突起９０ができてしまった。
【００２３】
なお、一般にはレジストパタン８７およびレジストパタン８９は液晶パネル１で液晶セルの透過部、遮光部として指定したパタンに対して投影露光倍率が掛かった大きさのパタンとなるが、対応が分かりにくくなるため、図１９ではレジストパタン８７およびレジストパタン８９の線幅を液晶セルの大きさに合わせて描いた。
【００２４】
アクティブマトリックス方式の液晶パネル１の場合には、ＴＦＴ１９も障害物となるため、くびれや突起がさらに顕著となってしまった。
【００２５】
応答速度や透過、不透過のコントラスト比等の観点から、最近の液晶パネル１の大半はＴＦＴ１９を用いている。ＴＦＴ１９は一般に液晶セル１０中の角部に配置されているので、それがあると、液晶セル１０の透過部の形状が長方形または正方形ではなくなり、連続した透過部を作ろうとすると、前記境界部８４の部分とつながったさらに大きい不透過部が形成され、転写パタンのくびれ８８や突起９０がより一層劣悪になるという課題があった。
【００２６】
このため、前記の液晶セル１０間の境界部８４をなるべく細くしたり、前記ＴＦＴ１９の寸法をできる限り小さくすることにより、形成されるパタンのくびれ８８や突起９０を極力抑える対処を行っていた。
【００２７】
しかしながら、境界部８４もアクティブマトリックス方式の液晶パネル１におけるＴＦＴ１９も必要不可欠であり、完全になくすことはできず、また、極力小さくするにしても限度があるため、形成されるパタンのくびれ８８や突起９０を十分小さくすることが困難であった。
【００２８】
従来の液晶マトリックス投影露光装置および液晶マトリックス投影露光方法においては、転写できるパタンの最小寸法は大略一つの液晶セル１０の大きさとなる。したがって、微細なパタンを転写するには液晶セル１０大きさが小さい程好ましい。しかしながら、液晶セル１０の大きさを小さくしてもそれに比例して前記境界部８４やＴＦＴ１９の大きさを小さくすることは困難なので、液晶セル１０の大きさが小さい程、くびれ８８や突起９０の問題が解決困難となっていた。
【００２９】
また、従来の液晶マトリックス投影露光装置および液晶マトリックス投影露光方法においては、転写できるパタンの単位寸法も大略一つの液晶セル１０の大きさとなるため、該液晶セル１０の大きさの整数倍の幅や大きさを持つパタンしか形成できなかった。したがって、液晶セル１０の大きさより小さい幅や大きさを有するパタンを形成することもできなかった。
【００３０】
また、従来の液晶マトリックス投影露光装置および液晶マトリックス投影露光方法においては、液晶セル１０の配置に従ってパタンが転写されるため、斜め線パタンは非常に形成しにくかった。
【００３１】
【課題を解決するための手段】
本発明は、前記の課題を解決するため、請求項１に示すように、パタン形状を透過部または不透過部として指定する液晶パネルと、該液晶パネルを照明する照明装置と、該液晶パネルで指定したパタンを被露光基板上に投影する投影光学系とを有する液晶マトリックス投影露光装置において、
前記液晶パネルに近接または密着させて、該液晶パネルの液晶セルの透過領域を一部のみに限定する、円形状、長円形状または任意の直線および／または曲線で構成する円形、長円形に類似した形状の開口を全ての液晶セルに対応して有する開口制御板を設け、
該開口制御板を介した状態で、前記液晶パネル上の透過部とされる点状または隣合う液晶セル同士による露光部がわずかに重なる程度に、第１の露光として被露光基板を投影露光し、
第１の露光の際の液晶パネルの位置に対し該液晶パネルを動かし或いは第１の露光の際の被露光基板の位置に対し該被露光基板の位置を動かすと共に、前記液晶パネル上にパタン形状を透過部または遮光部として指定し直し、前記開口制御板を介した状態で、該指定したパタン形状に被露光基板を投影露光することを特徴とする。
【００３２】
開口制御板の開口のｘ，ｙ方向の径または対辺長または対角長は、請求項２に示すように、ｘ，ｙ各方向につき、液晶セルピッチの８０％以上液晶セルピッチ以下としても良く、請求項３に示すように、ｘ，ｙ各方向につき、ｍを３以上の整数とする時、液晶セルピッチの２／ｍまたはその−２０％から＋２０％の範囲内に設定しても良い。
【００３３】
また、請求項４に示すように、該開口制御板を着脱するための待避・進入機構を付与し、従来の露光と切り替えて使用することができるすればなお良く、請求項５に示すように、開口制御板を該開口の形状および／または寸法を異として複数設け、任意の開口制御板を選択して択一着脱するための機構を有するようにすればさらに良い。
【００３４】
そして、パタンを転写するに当たっては、請求項６に示すように、液晶パネル中の液晶セルの透過領域を、円形状、長円形状または任意の直線および／または曲線で構成する円形、長円形に類似した形状で、ｘ，ｙ方向の径または対辺長または対角長を、ｘ，ｙ各方向につき、液晶セルピッチの８０％以上液晶セルピッチ以下とした開口を全ての液晶セルに対応して有する開口制御板により限定して各液晶セルの一部のみを透過部として残し、
該液晶パネル上にパタン形状を透過部または遮光部として指定して、前記開口制御板の開口を通過させつつ該指定したパタン形状に被露光基板を投影露光する第１の工程と、
第１の工程における該液晶パネルまたは被露光基板の位置に対し、該液晶パネルの位置を液晶セルのｘ方向ピッチの１／２だけｘ方向に動かすか、または被露光基板の位置を（ｘ方向液晶セルピッチ）×（投影露光倍率）の１／２だけｘ方向に動かし、
前記液晶パネル上にパタン形状を透過部または遮光部として指定し直し、前記開口制御板の開口を通過させつつ該指定したパタン形状に被露光基板を投影露光する第２の工程と、
第１の工程における該液晶パネルまたは被露光基板の位置に対し、該液晶パネルの位置を液晶セルのｙ方向ピッチの１／２だけｙ方向に動かすか、または被露光基板の位置を（ｙ方向液晶セルピッチ）×（投影露光倍率）の１／２だけｙ方向に動かし、
前記液晶パネル上にパタン形状を透過部または遮光部として指定し直し、前記開口制御板の開口を通過させつつ該指定したパタン形状に被露光基板を投影露光する第３の工程と、
第１の工程における該液晶パネルまたは被露光基板の位置に対し、第１の工程における該液晶パネルまたは被露光基板の位置に対し、該液晶パネルの位置をｘ方向に液晶セルのｘ方向ピッチの１／２とｙ方向に液晶セルのｙ方向ピッチの１／２だけ動かすか、または被露光基板の位置をｘ方向に（ｘ方向液晶セルピッチ）×（投影露光倍率）の１／２、ｙ方向に（ｘ方向液晶セルピッチ）×（投影露光倍率）の１／２だけ動かし、
前記液晶パネル上にパタン形状を透過部または遮光部として指定し直し、前記開口制御板の開口を通過させつつ該指定したパタン形状に被露光基板を投影露光する第４の工程とを含むようにする。
【００３５】
また、請求項７に示すように、液晶パネル中の液晶セルの透過領域を、円形状、長円形状または任意の直線および／または曲線で構成する円形、長円形に類似した形状で、ｍを３以上の整数とする時、ｘ，ｙ方向の開口の径または対辺長または対角長がそれぞれ液晶セルピッチの２／ｍまたはその−２０％から＋２０％の範囲内に設定した開口を全ての液晶セルに対応して有する開口制御板により限定して各液晶セルの一部のみを透過部として残し、
該液晶パネル上にパタン形状を透過部または遮光部として指定して、前記開口制御板の開口を通過させつつ該指定したパタン形状に被露光基板を投影露光する第１の工程と、
第１の工程における該液晶パネルまたは被露光基板の位置に対し、ｎを０またはｍより小さい任意の正の整数とする時、該液晶パネルの位置を、第１の露光位置に対して、ｘ方向および／またはｙ方向に液晶セルピッチのｎ／ｍ動かすか、または、被露光基板を（セルピッチのｎ／ｍ）×（投影露光倍率）に相当する距離だけ動かし、
前記液晶パネル上にパタン形状を透過部または遮光部として指定し直し、前記開口制御板の開口を通過させつつ該指定したパタン形状に被露光基板を投影露光する任意の工程とを含むようにする。
【００３６】
【発明の実施の形態】
このように、本発明の液晶マトリックス投影露光装置および液晶マトリックス投影露光方法は、開口制御板を用いて従来の液晶セルの中に、パタンを連結して形成するのに適した形状、寸法を有する、小さい透過部を設定することを課題を解決するための実施形態としている。発想を変えて、従来よりセル内の不透過部を増やす点に特徴がある。
【００３７】
また、液晶セルの開口を制限するのと同時に、多重露光してパタンを形成し、これにより、突起やくびれのほとんど無い滑らかな転写パタンを形成するとともに、液晶セルの大きさよりも微細なパタンや液晶セルピッチより小さいピッチのパタンを形成できるようにする。また、従来の液晶マトリックス投影露光装置および液晶マトリックス投影露光方法では形成しにくかった斜め線パタンも形成可能とする。
【００３８】
【実施例】
本発明の実施例を図面に基づいて詳細に説明する。
図１および図２は本発明の液晶マトリックス投影露光装置の構成図である。第４６回応用物理学関係連合講演会講演予稿集７４２ページ（１９９９）やＪａｐａｎｅｓｅＪｏｕｒｎａｌｏｆＡｐｐｌｉｅｄＰｈｙｓｉｃｓＶｏｌ．３８，ｐｐ．３２４−３２９（２０００）に開示された従来の装置との最大の相違点は、図１に示すように液晶パネル１の射出面に密着または近接させるか、図２に示すように液晶パネル１の入射面に密着または近接させ、各液晶セルの位置に対応させて、セルの一部のみを所定の形状の透過部として残すための開口制御板２を設けた点である。
【００３９】
液晶パネル１を光源と照明光学系とからなる照明装置３によって照明し、照明光４によって液晶パネル１上のパタン形状を投影光学系５を介して被露光基板６上に投影し、該被露光基板６上に付した感光性材料７を液晶パネル１に指定した透過部のパタンに開口制御板２の開口形状を重ねた形に感光させる。
【００４０】
８は液晶パネル１上にパタン形状を指定するためのパタン指定部である。パタンデータをパタン形状として表示するディスプレイ、指示を与えるためのキーボード、パタンデータを処理したり、記憶したり、検査するコンピュータ等で構成する。液晶パネル１とパタン指定部８とを結ぶ線９は両者がケーブル等で結合されていることを意味する。
【００４１】
液晶パネル１の液晶セル配置と開口制御板２の開口配置の例を図３に示す。縦横で転写パタンのでき方をほぼ同じにするためには、液晶パネル１上の液晶セルピッチがｘ方向とｙ方向で等しく液晶セル１０が正方形であることが好ましい。そこで、図３（ａ）には液晶セルピッチがｘ方向とｙ方向で等しく液晶セル１０が正方形であるの場合の液晶パネル１の液晶セル配置例を示した。これに対し、図３（ｂ）が適合する開口制御板２の例である。照明光線が不透過の基板１１に直径が液晶セルピッチの８０％以上液晶セルピッチ以下の円形開口１２を設けてある。
【００４２】
図４は図３に示した開口制御板２の円形開口１２と液晶セル１０との相対位置関係を詳細に示した図であり、図中の１０は正方形をした任意の液晶セル、１３、１４、１５、１６は液晶セル１０に隣接する正方形の液晶セル、一点鎖線１７、１８は任意の液晶セル１０と隣接する液晶セル１３、１４、１５、１６との境界部の中心線である。円形開口１２は図４（ａ）に示すように液晶セル１０をはみ出しても良く、図４（ｂ）に示すように液晶セル１０の中に収めても良い。
【００４３】
液晶セル１０内にＴＦＴ１９が存在する場合には、図４（ｃ）に示すように、できるだけ円形開口１２が該ＴＦＴ１９と重畳しないようにする。必ずしも円形開口１２の中心が液晶セル１０の中心と一致する必要はない。
【００４４】
図５は液晶セルピッチがｘ方向とｙ方向で等しく液晶セル１０が正方形である開口制御板２の円形以外の開口形状の例を示す。図５（ａ）は円に類似の任意曲線による開口２０、図５（ｂ）は正方形の四隅に面取りを付した開口２１、図４（ｃ）は多角形状の開口２２の例である。また、図５（ｄ）、図５（ｅ）、図５（ｆ）は多角形の開口の角に任意の丸みを設けた開口２３、２４、２５の例である。
【００４５】
なお、多角形の開口または多角形の角に丸みを持たせた開口の場合の角の数は任意で良い。
【００４６】
また、丸みを持たせるための曲線は必ずしも円弧である必要はなく任意で良い。そして、辺と角の丸みを形成する曲線とは交わっても接しても良い。
【００４７】
開口制御板２は照明光線が不透過の薄板または薄膜に穴状の開口を形成しても良く、照明光４を透過するガラスや石英等の透過基板上に遮光膜を付け、該遮光膜を開口の形状に除去しても良い。
【００４８】
図３、図４、図５に示したような開口を有する開口制御板２を入れた状態で、パタン指定部８から液晶パネル１の各液晶セルの透過、遮光を指定し、照明装置３からの照明光４によって液晶パネル１を照明して投影光学系５を介して液晶セル１０の透過、不透過で指定されるパタン形状を被露光基板６上に投影し、該被露光基板６上に付した感光性材料７を感光させる。
【００４９】
図６は、本発明の液晶マトリックス投影露光方法を説明する図であり、液晶パネル１上の透過および遮光の指定と被露光基板６上の転写パタンとの関係を例示している。たとえば、図６（ａ）に示すように、斜線を施した部分を遮光液晶セル２６とし、２７を開口制御板２で透過領域を制限した透過液晶セルとして第１の露光を行う。液晶マトリックスの規模は任意であり、ｘ軸、ｙ軸を図のように取って、ｙ軸およびｘ軸から図示の液晶マトリックス迄の距離をそれぞれａ、ｂとする。
【００５０】
被露光基板６上に付した感光性材料７は、図６（ｂ）に示すように、点状または隣合う透過液晶セル２７どうしによる露光部がわずかに重なる程度に感光する。２８が感光性材料７の露光部である。露光部の重なり方、離れ方は、開口制御板２の開口の大きさ、形状や露光量、感光性材料７の種類、厚さ等に依存する。
【００５１】
なお、一般には感光性材料７の露光部２８は開口制御板２で透過領域を制限した透過液晶セル２７に対して投影露光倍率が掛かった大きさとなるが、対応が分かりにくくなるため、図６（ｂ）では感光性材料７の露光部２８の大きさを開口制御板２で透過領域を制限した透過液晶セル２７の大きさに合わせて描いた。
【００５２】
次に、液晶パネル１を液晶セルピッチｐの１／２動かすか、または、被露光基板６を（液晶セルピッチｐの１／２）×（投影露光倍率）に相当する距離だけ動かし、液晶パネル１の液晶セルの透過、遮光を設定し直して第２の露光を行う。たとえば、図６（ｃ）に示すように、液晶パネル１をｙ方向に液晶セルピッチｐの１／２動かし、斜線を施した部分を遮光液晶セル２９とし、３０を開口制御板２で透過領域を制限した透過液晶セルとして第２の露光を行う。この結果、図６（ｄ）の３１が第２の露光による感光性材料７の露光部となる。重ねて描いた２８が前記第１の露光により露光された部分である。
【００５３】
次に、液晶パネル１を第１の露光の場合の位置に対して前記の第２の露光の場合と直交する方向に、液晶セルピッチｐの１／２動かすか、または、被露光基板６を（液晶セルピッチｐの１／２）×（投影露光倍率）に相当する距離だけ動かし、液晶パネル１の液晶セルの透過、遮光を設定し直して第３の露光を行う。たとえば、図５（ｅ）に示すように、液晶パネル１を今度はｘ方向に液晶セルピッチｐの１／２動かし、斜線を施した部分を遮光液晶セル３２とし、３３を開口制御板２で透過領域を制限した透過液晶セルとして第３の露光を行う。この結果、図６（ｆ）の３４が第３の露光による感光性材料７の露光部となる。重ねて描いた３５は前記第１の露光および第２の露光より露光された部分である。
【００５４】
さらに、液晶パネル１を第１の露光の場合の位置に対して、前記第２の露光の際に動かした方向および第３の露光の際に動かした方向の双方に、液晶セルピッチｐの１／２動かすか、または、被露光基板６を（液晶セルピッチｐの１／２）×（投影露光倍率）に相当する距離だけ動かし、液晶パネル１の液晶セルの透過、不透過を設定し直して第４の露光を行う。たとえば、図５（ｇ）に示すように、液晶パネル１を今度はｘ方向およびｙ方向にそれぞれ液晶セルピッチｐの１／２ずつ動かし、斜線を施した部分を遮光液晶セル３６とし、３７を開口制御板２で透過領域を制限した透過液晶セルとして第４の露光を行う。この結果、図６（ｈ）の３８が第４の露光による感光性材料７の露光部となる。重ねて描いた３９は前記第１の露光、第２の露光および第３の露光により露光された部分である。
【００５５】
上記のように第１の露光、第２の露光、第３の露光、第４の露光を行うと、感光性材料７は、露光領域が重なる場所では複数回露光される。
【００５６】
露光を行う際に、液晶パネル１または被露光基板６を所定の距離動かすには、図示してないが、それぞれが搭載されているステージを移動させれば良い。
【００５７】
ところで、パタンを投影露光する場合、投影光学系５によって被露光基板６上に形成されるパタンの光像は、液晶パネル１上の元々のパタンに対して強度分布の広がりを持って形成される。
【００５８】
そして、パタン光像の強度分布の広がり方は主として投影光学系５の開口数、収差等の光学特性や液晶パネル１を照明する照明光４のコヒーレンス係数等の照明条件等によって決まる。
【００５９】
この結果、露光後に現像した時に得られる感光性材料７のパタン寸法は常に一定ということにはならず、被露光基板６上に形成されるパタン光像の強度分布の広がりと露光量に応じて変動する。
【００６０】
したがって、第１の露光から第４の露光迄の４回の露光それぞれによって点状に露光された感光性材料７のパタンの形状、寸法は各場所毎に受けた合計露光量により変動し、４回の露光によって２回以上露光された部分とそれらの周辺は、露光量が１回だけ露光された場所より遠く迄露光の影響が及ぶ。
【００６１】
このため、点状の感光箇所を一部を重ねて図６のように第１の露光から第４の露光迄の４回の露光を行い、開口制御板２の開口の大きさに応じた露光量を選択すれば、露光領域の谷間となるパタン同士のつなぎ部分は露光が重なるため、それぞれの露光による光強度分布の重畳によって、１回だけ露光される場所の光強度と同程度にすることができる。すなわち、点状の露光箇所をその一部を重ねて連ねることにより、図７に示すようにその包絡線に類似したほぼ滑らかに連続した転写パタン４０を形成することができる。
【００６２】
この際、円形の微細露光領域をどの位重ねて露光を繰り返せばパタン４０が滑らかに連続して形成されるかが問題となるが、おおむね円形の半径ないしは半径の１．２倍より短い間隔で露光すればほぼ滑らかなパタンとなる。したがって、上記の第１の露光から第４の露光迄の４回の露光における露光距離間隔が最低限度の適正間隔である。より短い間隔で露光を行っても、接続状況の滑らかさがあまり改善されない一方で、露光回数が増加するため、合計所要時間が長くなつてしまう。一方、より長い距離間隔で露光すると、パタンの接続痕が出やすくなる。
【００６３】
第１の露光と第４の露光とが重なる部分は、円形の微細露光領域間の距離がｘ方向、ｙ方向に露光を重ねる場合より大きくなるため、ｘ方向、ｙ方向のパタンと比べると若干凹凸が残るものの、斜めのパタンがほぼ滑らかに形成される。従来のように、液晶パネル１で透過部を斜め方向に指定すると、四角形の露光部の角同士が連なることになり、パタン間に隙間ができてつながらなかったり、御幣状のパタンになったりしたが、それと比較すると、改善は顕著である。
【００６４】
なお、第１の露光から第４の露光迄の４回の露光の露光順序は任意であり、必ずしも図５に示した順序とする必要はない。
【００６５】
また、液晶パネル１または被露光基板６を図５では＋ｘまたは＋ｙ方向に動かしたが、−ｘまたは−ｙ方向に動かしても良い。
【００６６】
被露光基板６上に多数の同じパタンを転写する場合には、第１の露光から第４の露光迄の４回の露光を順次繰り返しても良いが、第１の露光だけ必要な回数をそれぞれの場所に行った後、液晶パネル１上のパタンを変更して第２の露光を行い、次にまた液晶パネル１上のパタンを変更して第３の露光を行い、最後にまた液晶パネル１上のパタンを変更して第４の露光を行うというように、液晶パネル１上のパタンが同じになる露光を連続して行っても良い。液晶パネル１上のパタンの変更回数が減るため、パタンの転写に要する時間を短縮することができる。
【００６７】
ほぼ滑らかに連続したパタンが形成できるのは、開口制御板２の開口形状が図５に示した形状であることと密接に関係しており、従来のように縦横方向の辺を有する正方形や長方形セルのままで複数回の露光を行って一部を重ねるようにしてもうまくは行かない。
【００６８】
図８は従来のように正方形を有するセルのままで複数回の露光を行って一部を重ねるようにした例である。図８（ａ）に示すように、斜線を施した部分を遮光液晶セル４１とし、４２を透過液晶セルとして第１の露光を行う。被露光基板６上に付した感光性材料７は、図８（ｂ）に示すように、点状または隣合う透過液晶セル４２どうしによる露光部がわずかに重なる程度に感光する。４３が感光性材料７の露光部である。
【００６９】
なお、一般には感光性材料７の露光部４３は透過液晶セル４２に対して投影露光倍率が掛かった大きさとなるが、対応が分かりにくくなるため、図８（ｂ）では感光性材料７の露光部４３の大きさを透過液晶セル４２の大きさに合わせて描いた。
【００７０】
次に、本発明と同様に液晶パネル１を液晶セルピッチｐの１／２動かすか、または、被露光基板６を（液晶セルピッチｐの１／２）×（投影露光倍率）に相当する距離だけ動かし、液晶パネル１の液晶セルの透過、不透過を設定し直して第２の露光を行う。たとえば、図８（ｃ）に示すように、液晶パネル１をｙ方向に液晶セルピッチｐの１／２動かし、斜線を施した部分を遮光液晶セル４４とし、４５を透過液晶セルとして第２の露光を行う。この結果、図８（ｄ）の４６が第２の露光による感光性材料７の露光部となる。重ねて描いた４３が前記第１の露光により露光された部分である。
【００７１】
しかし、このように開口制御板２が付いていない状態では、液晶セル幅いっぱいに２回の露光が重なるため、被露光基板６の透過液晶セル４５に相当する場所の外側に光強度分布が広がる部分ができてしまう。したがって、感光性材料６がポジ形の場合には、図９（ａ）に示すように現像後のレジストパタン４７に凹み４８ができ、ネガ形の場合には、現像後のレジストパタン４９に突起５０ができてしまう。
【００７２】
開口制御板２の開口の大きさはさらに小さくても良く、ｍを３より大きい整数とする時、円形状、長円形状または任意の直線および／または曲線で構成する円形、長円形に類似した形状で、ｘ，ｙ方向の開口の径または対辺長または対角長がそれぞれ液晶セルピッチの２／ｍまたはその−２０％から＋２０％の範囲内に設定しても良い。
【００７３】
図１０にｍ＝３の場合の実施例を示す。図は複数回の露光により感光性材料７が順次露光される状況を示している。開口の形状は図５と同様で良い。
【００７４】
この実施例においては、まず、開口の大きさを、開口制御板２の開口のｘ，ｙ方向の径または対辺長または対角長を液晶セルピッチｐの２／３またはその−２０％から＋２０％の範囲内に設定し、液晶パネル１の液晶セルの透過、遮光を設定して第１の露光により、図１０（ａ）に示すように、液晶セルピッチｐに相当する間隔で点状に露光する。
【００７５】
５１が被露光基板６上の感光性材料７の露光部である。露光部５１は、開口制御板２の開口の大きさに投影露光倍率が掛かった大きさとなる。
【００７６】
次に、液晶パネル１をｘ方向またはｙ方向に液晶セルピッチｐの１／３動かすか、または、被露光基板６を（液晶セルピッチｐの１／３）×（投影露光倍率）に相当する距離だけ動かし、液晶パネル１の液晶セルの透過、遮光を設定し直して、図１０（ｂ）に示すように、第２の露光を行う。５２が第２の露光による露光部である。ここでは一例として液晶パネル１をｙ方向に動かす場合を示した。
【００７７】
さらに、液晶パネル１を第１の露光を行った位置に対してｙ方向に液晶セルピッチの２／３動かすか、被露光基板６をｙ方向に（液晶セルピッチの２／３）×（投影露光倍率）に相当する距離だけ動かし、液晶パネル１のセルの透過、遮光を設定し直して第３の露光を行う。図１０（ｃ）の５３は第３の露光による露光部、５４は第１の露光と第２の露光による露光部である。
【００７８】
次に、液晶パネル１を第１の露光を行った位置に対してｘ方向に液晶セルピッチの１／３動かすか、被露光基板６をｘ方向に（液晶セルピッチの１／３）×（投影露光倍率）に相当する距離だけ動かし、液晶パネル１のセルの透過、遮光を設定し直して第４の露光を行う。図１０（ｄ）の５５は第４の露光による露光部、５６は第１の露光からと第３の露光までのいずれかの露光による露光部である。
【００７９】
さらに、液晶パネル１を第１の露光を行った位置に対してｘ方向に液晶セルピッチの２／３動かすか、被露光基板６をｘ方向に（液晶セルピッチの２／３）×（投影露光倍率）に相当する距離だけ動かし、液晶パネル１のセルの透過、遮光を設定し直して第５の露光を行う。図１０（ｅ）の５７は第５の露光による露光部、５８は第１の露光からと第４の露光までのいずれかの露光による露光部である。
【００８０】
次に、液晶パネル１を第１の露光を行った位置に対してｘ方向に液晶セルピッチの１／３、ｙ方向に液晶セルピッチの２／３動かすか、被露光基板６をｘ方向に（液晶セルピッチの１／３）×（投影露光倍率）、ｙ方向に（液晶セルピッチの２／３）×（投影露光倍率）に相当する距離だけ動かし、液晶パネル１のセルの透過、遮光を設定し直して第６の露光を行う。図１０（ｆ）の５９は第６の露光による露光部、６０は第１の露光からと第５の露光までのいずれかの露光による露光部である。
【００８１】
さらに、液晶パネル１を第１の露光を行った位置に対してｘ方向に液晶セルピッチの２／３、ｙ方向に液晶セルピッチの１／３動かすか、被露光基板６をｘ方向に（液晶セルピッチの２／３）×（投影露光倍率）、ｙ方向に（液晶セルピッチの１／３）×（投影露光倍率）に相当する距離だけ動かし、液晶パネル１のセルの透過、遮光を設定し直して第７の露光を行う。図１０（ｇ）の６１は第７の露光による露光部、６２は第１の露光からと第６の露光までのいずれかの露光による露光部である。
【００８２】
図８には以上に示した第７の露光迄しか示していないが、必要に応じて、液晶パネル１を第１の露光を行った位置に対してｘ方向に液晶セルピッチの１／３、ｙ方向に液晶セルピッチの１／３動かすか、被露光基板６をｘ方向に（液晶セルピッチの１／３）×（投影露光倍率）、ｙ方向に（液晶セルピッチの１／３）×（投影露光倍率）に相当する距離だけ動かし、液晶パネル１のセルの透過、遮光を設定し直して第８の露光を行う。
【００８３】
また、必要に応じて、液晶パネル１を第１の露光を行った位置に対してｘ方向に液晶セルピッチの２／３、ｙ方向に液晶セルピッチの２／３動かすか、被露光基板６をｘ方向に（液晶セルピッチの２／３）×（投影露光倍率）、ｙ方向に（液晶セルピッチの２／３）×（投影露光倍率）に相当する距離だけ動かし、液晶パネル１のセルの透過、遮光を設定し直して第９の露光を行う。
【００８４】
第８の露光、第９の露光に限らず、各露光は所望するパタンの形状に応じて省略しても良い。
【００８５】
なお、複数回行う露光の露光順序は任意であり、必ずしも図１０に示した順序とする必要はない。
【００８６】
また、液晶パネル１または被露光基板６を図８では＋ｘまたは＋ｙ方向に動かしたが、−ｘまたは−ｙ方向に動かしても良い。
【００８７】
これらの複数回の露光によって、開口制御板２の開口の大きさに応じた露光量を選択すれば、図５の場合と同様、露光領域の谷間となるパタン同士のつなぎ部分は露光が重なるため、それぞれの露光による光強度分布の広がりの重畳によって、１回だけ露光される場所の光強度と同程度にすることができる。すなわち、点状の露光箇所をその一部を重ねて連ねることにより、図１１に示すようにその包絡線に類似したほぼ滑らかに連続したパタン６３を形成することができる。
【００８８】
ｍ≧４の場合には、ｎを０またはｍより小さい正の整数とする時、第１の露光位置に対して、ｘおよび／またはｙ方向に液晶セルピッチｐのｎ／ｍ動かすか、または、被露光基板６を（セルピッチのｎ／ｍ）×（投影露光倍率）に相当する距離だけ動かし、液晶パネル１のセルの透過、遮光を設定し直して、次々に露光を行う。
【００８９】
上記の複数の露光は任意の順序で行って良い。
【００９０】
このように露光すると、先の図６および図１０に示したのと同様に、被露光基板６上の感光性材料７は、複数回の露光で点状に露光した部分の全部を包絡した形に露光される。
【００９１】
そのため、現像後形成される感光性材料６のパタンは、露光部分のつなぎ目に相当する凹凸が平滑化された滑らかな外形形状となる。
【００９２】
図６、図１０の場合を含め、パタン側壁の平滑化のされ具合は、開口制御板２の開口の形状、寸法のほか、感光性材料７の種類や厚さ、投影光学系５の開口数、照明光４の露光波長やコヒーレンス度等により異なるが、露光量を選べば、円や多角形等がつながって露光されたとは思えない滑らかさとなる。
【００９３】
また、露光量が最適でない条件でも、従来の投影露光装置および方法において液晶セル全体を単位として転写パタンをつなぎ合わせる場合と比較すると、液晶セル境界やＴＦＴに対応する部分に起因するパタンの劣化かないため、格段に滑らかな外形形状を有するパタンを得ることができる。
【００９４】
なお、開口制御板２の開口の径またはｘ，ｙ方向の対辺長または対角長を、ｍを３以上の整数とする時、液晶セルピッチの２／ｍまたはその−２０％から＋２０％の範囲内に設定すれば、（液晶セルピッチｐの約２／ｍ前後）×（投影露光倍率）という従来の約２／ｍの微細パタンを形成することができる。
【００９５】
また、（液晶セルピッチｐの約２／ｍ前後）×（投影露光倍率）のパタンを（液晶セルピッチｐの約１／ｍ）ずつ液晶パネル１を動かして露光するか、（液晶セルピッチｐの約１／ｍ）×（投影露光倍率）ずつ被露光基板６を動かして露光することにより、従来転写できたパタンの２／ｍの微細ピッチのパタンを形成することができる。
【００９６】
図１２は一例として、ｍ＝３の場合に、図１０に示した方法によって、従来の２／３の線幅で２／３のピッチのパタンが形成できる例を示す。図１２（ａ）は露光場所の重なりを表しており、６４が開口制御板２の開口１個に相当する露光場所である。また、図１２（ｂ）は現像後得られる感光性材料７のパタン形状である。図は感光性材料７としてポジ形レジストを使用した場合を示しており、６５がレジスト、６６が現像後レジストが除去されてできたパタンである。
【００９７】
なお、以上の説明では液晶セルピッチがｘ方向とｙ方向とで等しいとして説明した。しかし、必ずしも液晶セルピッチがｘ方向とｙ方向とで等しくなくても本発明が有効なことは明らかである。
【００９８】
たとえば縦長の液晶セルを有し、ｙ方向の液晶セルピッチがｘ方向の液晶セルピッチより長い場合には、開口制御板２の開口の形状を図１３に例示するような形状とすれば良い。
図１３（ａ）は任意曲線からなる長円形の開口６７、図１３（ｂ）、図１３（ｃ）は多角形状の開口６８、６９、図１３（ｄ）、図１３（ｅ）、図１３（ｆ）は多角形の角を丸めた形状７０、７１、７２である。開口の大きさや露光時に液晶パネル１や被露光基板６を動かす距離はｘ方向、ｙ方向別々にそれぞれの方向の液晶セルピッチを基準にして決めれば良い。
【００９９】
ところで、本発明により上記のように複数回の露光を重ね合わせることによってパタンを形成すると、露光回数に応じてパタン形成に要する時間が長くなってしまう。したがって、必要に応じて適切な大きさの開口を有する開口制御板２を取り付けられるように構成しておけば、より便利である。
【０１００】
図１４は開口制御板２を着脱するための待避・進入機構を設けた本発明の液晶マトリックス投影露光装置である。案内機構７３上を開口制御板２を載せたキャリッジ７４が動く構造になっており、図に実線で示した待避位置にある開口制御板２を二点鎖線で示した使用位置７５に搬入する。
【０１０１】
転写されるパタンに多少の凹みや突起があっても良い場合には開口制御板２を待避させ、滑らかなパタンが必要な時に開口制御板２を装着する。
【０１０２】
開口制御板２を着脱するための待避・進入機構は任意で良く、後述の図１５に示すように回転アームを利用した待避・進入機構を設けたり、伸縮するアームを使用したりしても良い。
【０１０３】
図１５は複数の開口制御板を交換可能とした液晶マトリックス投影露光装置である。開口制御板ストッカー７６に複数の開口制御板を用意しておく。図には７７、７８、７９で示す３枚の開口制御板を描いたが、ストックする枚数は任意である。
【０１０４】
回転支柱８０に開口制御板を保持して回転および上下する回転アーム８１がついており、必要とする開口制御板を選択して液晶パネル１に装着する。
【０１０５】
この場合も開口制御板を着脱するための待避・進入機構は任意で良く、図１４に示したように案内機構上を開口制御板７７、７８、７９を載せたキャリッジが動くようにしたり、伸縮するアームを利用したりしても良い。なお、二点鎖線で示した８２は開口制御板の使用位置を示している。
【０１０６】
【発明の効果】
以上に説明したように、本発明の液晶マトリックス投影露光装置および液晶マトリックス投影露光方法によれば、液晶セル間に露光光線が不透過となる境界部が存在しても、また、液晶セル内に露光光線が不透過となるＴＦＴが設けられていても、接続したことが目立たない滑らかな外形形状のパタンを転写形成することができる。
【０１０７】
また、斜め線パタンも従来よりはるかに滑らかに転写形成することができる。
【０１０８】
さらに、開口制御板の開口の大きさを小さくすることにより、仕様する液晶パネルの液晶セルの大きさや液晶セルピッチが同じでも、従来より微細なパタンや従来よりパタンピッチの小さいパタンを転写することができる。
従来よりパタンピッチの小さいパタンを転写することができる。
【０１０９】
なお、開口制御板の開口の大きさを小さくすることにより、複数回の露光が必要となるが、液晶セルピッチの整数分の１の距離間隔で露光するため、露光回数の増加は必要最低限度の回数となる。
【図面の簡単な説明】
【図１】本発明の液晶マトリックス投影露光装置の構成図である。
【図２】本発明の液晶マトリックス投影露光装置の別の構成図である。
【図３】液晶パネルのセル配置と開口制御板の開口との関係である。
【図４】液晶セルと開口制御板の開口との位置関係の詳細図である。
【図５】正方形液晶セルに対する開口制御板の開口形状の例である。
【図６】本発明の液晶マトリックス投影露光方法の説明図である。
【図７】図６に示した本発明の方法により転写されるパタン形状である。
【図８】開口制御板を用いずに接続露光を行った時の露光状況である。
【図９】開口制御板を用いずに接続露光を行った時の転写パタン形状である。
【図１０】本発明の別の液晶マトリックス投影露光方法の説明図である。
【図１１】図１０示した本発明の方法により転写されるパタン形状である。
【図１２】微細幅、微細ピッチのパタンが形成できる例の説明図である。
【図１３】ｘ方向、ｙ方向で液晶セルピッチが異なる液晶セルに対する開口制御板の開口形状の例である。
【図１４】開口制御板を着脱するための待避・進入機構を設けた本発明の液晶マトリックス投影露光装置の構成図である。
【図１５】複数の開口制御板を交換可能とした本発明の液晶マトリックス投影露光装置の構成図である。
【図１６】従来の原図基板を用いる投影露光装置の構成図である。
【図１７】従来の液晶マトリックス投影露光装置の構成図である。
【図１８】液晶パネル１の模式図である。
【図１９】従来の液晶マトリックス投影露光装置によって形成したパタン形状の説明図である。
【符号の説明】
１液晶パネル
２開口制御板
３照明装置
４照明光
５投影光学系
６被露光基板
７感光性材料
８パタン指定部
１０液晶セル
２０、２１、２２、２３、２４、２５開口の形状例
２６２９、３２、３６遮光液晶セル
２７、３０、３３、３７透過液晶セル
２８、３１、３４、３５、３８、３９露光部
４０転写パタン
７３案内機構
７４キャリッジ
７６開口制御板ストッカー
８０回転支柱
８１回転アーム[0001]
[Industrial field to which the invention pertains]
The present invention relates to an apparatus and a method for transferring a fine pattern such as a semiconductor integrated circuit, an optoelectronic element, a micromachine part or the like onto a substrate to be exposed such as a semiconductor wafer.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, projection exposure apparatuses and projection exposure methods have been widely used to form fine patterns such as semiconductor integrated circuits, optoelectronic elements, and micromachine parts on various substrates such as semiconductor wafers, metal substrates, and glass substrates.
[0003]
FIG. 16 is a block diagram of a conventional projection exposure apparatus. In order to perform projection exposure using this conventional projection exposure apparatus, a reticle formed with a light-shielding body such as chromium on a light transmission substrate such as synthetic quartz or glass, or a frame such as a silicon wafer is used. A stencil mask in which pattern-shaped holes to be an original drawing are formed in various thin films or thin metal plate plates provided is used as the original drawing substrate 83.
[0004]
Projection optical system 5 such as a projection lens, a projection mirror optical system, or an optical system in which the lens and the mirror are appropriately combined is irradiated with illumination light 4 on illumination source 3 composed of a light source and an illumination optical system. Is used to project the pattern on the original drawing substrate 83 onto the substrate 6 to be exposed.
[0005]
A photosensitive material 7 such as a resist is previously applied to the substrate 6 to be exposed, for example, a semiconductor wafer, a metal substrate, a glass substrate, or the like, by coating or spraying. Then, the photosensitive material 7 is exposed to a pattern shape corresponding to the shape of the transmission part of the original drawing substrate 83 by the illumination light beam 4 applied to the original drawing substrate 83.
[0006]
Accordingly, when development is performed after exposure, the photosensitive material 7 in the photosensitive part or the unexposed part is removed depending on whether the photosensitive material 7 is positive or negative, and the pattern shape on the original drawing substrate 83 is Transferred onto the substrate 6 to be exposed.
[0007]
As described above, the conventional projection exposure apparatus and projection exposure method are apparatuses and methods for transferring a pattern on the original drawing substrate 83 such as a reticle and a stencil mask to a photosensitive material on the substrate 6 to be exposed. An original drawing substrate 83 having a pattern corresponding to the pattern was indispensable.
[0008]
If there are any errors or defects in the fine pattern that is formed on the original drawing substrate 83, all products using the transferred pattern will be defective, so inspection and confirmation are important. Expensive. The pattern is not only a shape but also various precisions such as line width, hole size, and their position, so that the pattern becomes particularly expensive when the pattern becomes fine.
[0009]
On the other hand, with the diversification of social consumption trends, products tend to be produced in a variety of small quantities. For example, in semiconductor integrated circuit products, while ICs for specific applications are growing, examples of producing the same product in a very large amount are limited to a very small part such as a memory.
[0010]
In general, micromachine parts and the like, for which many general-purpose products have not yet been available, are produced in an extremely small amount compared to semiconductor integrated circuit products from the beginning.
[0011]
However, since the original drawing substrate 83 having the original pattern is required as long as projection exposure is performed regardless of the amount of production, the price of the original drawing substrate 83 greatly affects the product price in a small-volume product. .
[0012]
In addition, it is almost impossible to change or modify the pattern on the original drawing substrate 83 except in special cases, and it is necessary to recreate the original drawing substrate 83 for each product and each pattern change.
[0013]
Therefore, recently, instead of recreating the conventional original drawing substrate 83 for each product and pattern change, each liquid crystal cell of the liquid crystal panel is used as a matrix switch for controlling transmission and shading of the original drawing substrate 83. The usefulness of the liquid crystal matrix projection exposure apparatus shown in FIG. 17 and the exposure method using the same, in which projection exposure is performed by designating a transmissive part and a light-shielding part in a predetermined arrangement, for example, is the 46th Applied Physics Pp. 742 (1999), Related Journal Lecture Proceedings, Japan Journal of Applied Physics Vol. 38, pp. 324-329 (2000).
[0014]
According to the liquid crystal matrix projection exposure apparatus and the liquid crystal matrix projection exposure method described above, transmission and shading of each cell of the liquid crystal panel 1 can be easily specified from the pattern specifying unit 8 by a keyboard operation or the like. Reference numeral 9 denotes that the liquid crystal panel 1 and the pattern designating unit 8 are connected by a cable or the like.
[0015]
Therefore, the original drawing substrate 83 having a fixed pattern such as a conventional reticle or stencil mask is not necessary.
[0016]
In addition, pattern design data can be easily converted automatically into control commands for each cell of the liquid crystal panel 1 by a personal computer or the like, so that transmission and non-transmission control of each cell of the liquid crystal panel 1 is automatically performed. It is also possible to do it manually.
[0017]
In addition, if the pattern design data is automatically converted into a control command to each cell of the liquid crystal panel 1 by a personal computer or the like, the pattern can be inspected using the design data. It can be greatly reduced, and pattern changes and modifications can be made very easily.
[0018]
[Problems to be solved by the invention]
However, the disclosed liquid crystal matrix projection exposure apparatus and liquid crystal matrix projection exposure method shown in FIG. 17 have the following problems.
[0019]
FIG. 18 is a schematic diagram of the liquid crystal panel 1. As shown in FIG. 18A, there is a boundary portion 84 between each liquid crystal cell 10 of the liquid crystal panel 1, and the boundary portion 84 is always non-transparent regardless of whether the cell portion is designated for transmission or light shielding. It is had.
[0020]
In the case of the simple matrix type liquid crystal panel 1, there is no obstacle in the liquid crystal cell 10, but in the case of the active matrix type liquid crystal panel 1, as shown in FIG. A thin film transistor (TFT) 19 is formed in the liquid crystal cell 10, and the TFT 19 portion is always impermeable in addition to the boundary portion 84.
[0021]
FIG. 19 is an explanatory diagram of a pattern shape formed by a conventional liquid crystal matrix projection exposure apparatus. Even when the simple matrix type liquid crystal panel 1 is used, even if an attempt is made to form a linear photosensitive portion by arranging continuous transmissive liquid crystal cells 86 in the light-shielding liquid crystal cell 85, the exposure amount of the portion corresponding to the boundary portion 84 is small. As a result, constrictions and protrusions were formed in the transfer pattern.
[0022]
For example, as shown in FIG. 19A, when projection exposure is performed by designating the shaded portion of the liquid crystal panel 1 as the light-shielded liquid crystal cell 85 and the white frame portion as the transmissive cell 86, originally a pattern on a straight line is required. When a negative resist is used as the photosensitive material 7, a resist pattern 87 as shown in FIG. 19B is formed, and a constriction 88 occurs in the transfer pattern. Further, when a positive resist is used as the photosensitive material 7, a resist pattern 89 as shown in FIG. 19C is formed, and a projection 90 is formed on the transfer pattern.
[0023]
In general, the resist pattern 87 and the resist pattern 89 are patterns having a size obtained by multiplying the projection exposure magnification with respect to the pattern designated as the transmission part and the light-shielding part of the liquid crystal cell in the liquid crystal panel 1, but the correspondence is difficult to understand. Therefore, in FIG. 19, the line widths of the resist pattern 87 and the resist pattern 89 are drawn in accordance with the size of the liquid crystal cell.
[0024]
In the case of the active matrix type liquid crystal panel 1, since the TFT 19 also becomes an obstacle, the constriction and the protrusion become more prominent.
[0025]
From the viewpoint of response speed, transmission and non-transmission contrast ratio, etc., most of the recent liquid crystal panels 1 use TFTs 19. Since the TFT 19 is generally arranged at the corner of the liquid crystal cell 10, the shape of the transmissive portion of the liquid crystal cell 10 is not rectangular or square when it is present. There is a problem that a larger non-transparent portion connected to this portion is formed, and the constriction 88 and the protrusion 90 of the transfer pattern are further deteriorated.
[0026]
For this reason, measures have been taken to minimize the constriction 88 and the protrusion 90 of the pattern to be formed by making the boundary portion 84 between the liquid crystal cells 10 as thin as possible or making the dimensions of the TFT 19 as small as possible.
[0027]
However, the boundary portion 84 and the TFT 19 in the active matrix type liquid crystal panel 1 are indispensable and cannot be completely eliminated, and there is a limit even if it is made as small as possible. It was difficult to make the protrusion 90 sufficiently small.
[0028]
In the conventional liquid crystal matrix projection exposure apparatus and liquid crystal matrix projection exposure method, the minimum size of the pattern that can be transferred is approximately the size of one liquid crystal cell 10. Therefore, the smaller the size of the liquid crystal cell 10 is preferable for transferring a fine pattern. However, even if the size of the liquid crystal cell 10 is reduced, it is difficult to reduce the size of the boundary portion 84 and the TFT 19 in proportion thereto. Therefore, the smaller the size of the liquid crystal cell 10, the smaller the constriction 88 and the protrusion 90. The problem was difficult to solve.
[0029]
Further, in the conventional liquid crystal matrix projection exposure apparatus and liquid crystal matrix projection exposure method, the unit dimension of the pattern that can be transferred is approximately the size of one liquid crystal cell 10, and therefore, the width of an integral multiple of the size of the liquid crystal cell 10 Only a pattern with a size could be formed. Therefore, a pattern having a width and size smaller than the size of the liquid crystal cell 10 cannot be formed.
[0030]
Further, in the conventional liquid crystal matrix projection exposure apparatus and liquid crystal matrix projection exposure method, since the pattern is transferred according to the arrangement of the liquid crystal cells 10, it is difficult to form the oblique line pattern.
[0031]
[Means for Solving the Problems]
  In order to solve the above-described problems, the present invention provides a liquid crystal panel that designates a pattern shape as a transmissive portion or a non-transmissive portion, an illuminating device that illuminates the liquid crystal panel, and the liquid crystal panel. In a liquid crystal matrix projection exposure apparatus having a projection optical system for projecting a designated pattern onto an exposure substrate,
  Similar to a circle, oval, or a circle or oval with a circular shape, an oval shape, or an arbitrary straight line and / or a curved line, which is close to or in close contact with the liquid crystal panel and restricts the transmission region of the liquid crystal cell of the liquid crystal panel to only a part. The shape of the openingFor all liquid crystal cellsAn opening control plate having,
  The substrate to be exposed is projected and exposed as the first exposure to the extent that the exposed portions of the dotted or adjacent liquid crystal cells that are the transmission portions on the liquid crystal panel slightly overlap with each other through the aperture control plate. ,
  The liquid crystal panel is moved with respect to the position of the liquid crystal panel at the time of the first exposure, or the position of the substrate to be exposed is moved with respect to the position of the substrate to be exposed at the time of the first exposure, and a pattern shape is formed on the liquid crystal panel. Is designated as a transmissive part or a light shielding part, and the exposed substrate is projected and exposed to the designated pattern shape through the aperture control plate.It is characterized by that.
[0032]
The diameter or opposite length or diagonal length of the opening of the opening control plate may be 80% or more of the liquid crystal cell pitch and less than or equal to the liquid crystal cell pitch in each of the x and y directions. As shown in Item 3, when m is an integer of 3 or more in each of the x and y directions, the liquid crystal cell pitch may be set to 2 / m or within a range of -20% to + 20%.
[0033]
Further, as shown in claim 4, it is more preferable that a retracting / entry mechanism for attaching and detaching the opening control plate is provided so that it can be used by switching from conventional exposure. It is further preferable to provide a plurality of opening control plates having different shapes and / or dimensions of the openings, and to have a mechanism for selecting and attaching / detaching an arbitrary opening control plate.
[0034]
  In transferring the pattern, as shown in claim 6, the transmission region of the liquid crystal cell in the liquid crystal panel is formed into a circular shape, an oval shape, or a circular shape or an oval shape formed of an arbitrary straight line and / or curved line. An opening having a similar shape and a diameter or opposite side length or diagonal length in the x and y directions of 80% or more of the liquid crystal cell pitch and less than or equal to the liquid crystal cell pitch in each of the x and y directions.Is limited by the opening control plate corresponding to all the liquid crystal cells, leaving only a part of each liquid crystal cell as a transmission part,
  Designate the pattern shape on the liquid crystal panel as a transmission part or a light-shielding part.While passing the opening of the opening control plateA first step of projecting and exposing the substrate to be exposed in the designated pattern shape;
  The position of the liquid crystal panel is moved in the x direction by ½ of the x direction pitch of the liquid crystal cell with respect to the position of the liquid crystal panel or the substrate to be exposed in the first step, or the position of the substrate to be exposed is changed to the x direction (x direction). (Liquid crystal cell pitch) x (projection exposure magnification) ½, move in the x direction,
  Respecify the pattern shape on the liquid crystal panel as a transmissive part or a light shielding part,While passing through the opening of the opening control plateA second step of projecting and exposing the substrate to be exposed to the designated pattern shape;
  The position of the liquid crystal panel is moved in the y direction by a half of the y direction pitch of the liquid crystal cell with respect to the position of the liquid crystal panel or the exposed substrate in the first step, or the position of the exposed substrate is changed to the y direction (y direction). (Liquid crystal cell pitch) x (projection exposure magnification) ½ in the y direction,
  Respecify the pattern shape on the liquid crystal panel as a transmissive part or a light shielding part,While passing through the opening of the opening control plateA third step of projecting and exposing the substrate to be exposed to the specified pattern shape;
  With respect to the position of the liquid crystal panel or the substrate to be exposed in the first step, the position of the liquid crystal panel is set to the x direction pitch of the liquid crystal cell with respect to the position of the liquid crystal panel or the substrate to be exposed in the first step. Move the half of the y-direction pitch of the liquid crystal cell in the 1/2 and y directions, or move the position of the substrate to be exposed in the x direction (x direction liquid crystal cell pitch) × 1/2 (projection exposure magnification), y direction (X-direction liquid crystal cell pitch) x (projection exposure magnification) ½,
  Respecify the pattern shape on the liquid crystal panel as a transmissive part or a light shielding part,While passing through the opening of the opening control plateAnd a fourth step of projecting and exposing the substrate to be exposed in the designated pattern shape.
[0035]
  According to a seventh aspect of the present invention, the transmission region of the liquid crystal cell in the liquid crystal panel has a circular shape, an oval shape, a circular shape constituted by an arbitrary straight line and / or a curved line, a shape similar to an elliptical shape, and m When the integer is 3 or more, the diameter, the opposite side length, or the diagonal length of the opening in the x and y directions is set to 2 / m of the liquid crystal cell pitch or within the range of -20% to + 20%, respectively.Is limited by the opening control plate corresponding to all the liquid crystal cells, leaving only a part of each liquid crystal cell as a transmission part,
  Designate the pattern shape on the liquid crystal panel as a transmission part or a light-shielding part.While passing the opening of the opening control plateA first step of projecting and exposing the substrate to be exposed in the designated pattern shape;
  When n is an arbitrary positive integer smaller than 0 or m with respect to the position of the liquid crystal panel or the substrate to be exposed in the first step, the position of the liquid crystal panel is set to x with respect to the first exposure position. Move the liquid crystal cell pitch n / m in the direction and / or y direction, or move the substrate to be exposed by a distance corresponding to (cell pitch n / m) × (projection exposure magnification),
  Respecify the pattern shape on the liquid crystal panel as a transmissive part or a light shielding part,While passing through the opening of the opening control plateAnd an arbitrary step of projecting and exposing the substrate to be exposed in the designated pattern shape.
[0036]
DETAILED DESCRIPTION OF THE INVENTION
As described above, the liquid crystal matrix projection exposure apparatus and the liquid crystal matrix projection exposure method of the present invention have a shape and size suitable for forming a pattern in a conventional liquid crystal cell using an aperture control plate. Therefore, setting a small transmission part is an embodiment for solving the problem. It is characterized by changing the way of thinking and increasing the number of opaque parts in the cell.
[0037]
At the same time as limiting the opening of the liquid crystal cell, multiple exposure is performed to form a pattern, thereby forming a smooth transfer pattern with almost no protrusions or constriction, and a pattern finer than the size of the liquid crystal cell. A pattern having a pitch smaller than the liquid crystal cell pitch can be formed. Further, it is possible to form an oblique line pattern that is difficult to form with the conventional liquid crystal matrix projection exposure apparatus and liquid crystal matrix projection exposure method.
[0038]
【Example】
Embodiments of the present invention will be described in detail with reference to the drawings.
1 and 2 are block diagrams of a liquid crystal matrix projection exposure apparatus of the present invention. Proceedings of the 46th Applied Physics Related Conference Lecture 742 (1999) and Japan Journal of Applied Physics Vol. 38, pp. The biggest difference from the conventional apparatus disclosed in 324-329 (2000) is that the liquid crystal panel 1 is brought into close contact with or close to the exit surface as shown in FIG. 1, or the liquid crystal panel 1 as shown in FIG. The aperture control plate 2 is provided in such a manner that only a part of the cell is left as a transmission part of a predetermined shape in close contact with or close to the incident surface and corresponding to the position of each liquid crystal cell.
[0039]
The liquid crystal panel 1 is illuminated by an illuminating device 3 including a light source and an illumination optical system, and the pattern shape on the liquid crystal panel 1 is projected onto the exposure substrate 6 via the projection optical system 5 by the illumination light 4, and the exposure object is exposed. The photosensitive material 7 applied on the substrate 6 is exposed in a shape in which the aperture shape of the aperture control plate 2 is superimposed on the pattern of the transmission portion designated on the liquid crystal panel 1.
[0040]
Reference numeral 8 denotes a pattern designating unit for designating a pattern shape on the liquid crystal panel 1. It comprises a display that displays pattern data as a pattern shape, a keyboard for giving instructions, a computer that processes, stores, and inspects pattern data. A line 9 connecting the liquid crystal panel 1 and the pattern designating portion 8 means that both are connected by a cable or the like.
[0041]
An example of the liquid crystal cell arrangement of the liquid crystal panel 1 and the opening arrangement of the opening control plate 2 is shown in FIG. In order to make the transfer pattern substantially the same in the vertical and horizontal directions, the liquid crystal cell pitch on the liquid crystal panel 1 is preferably equal in the x and y directions, and the liquid crystal cell 10 is preferably square. Therefore, FIG. 3A shows an example of the liquid crystal cell arrangement of the liquid crystal panel 1 when the liquid crystal cell pitch is the same in the x direction and the y direction and the liquid crystal cell 10 is square. On the other hand, FIG. 3B is an example of the opening control plate 2 to which it fits. A circular opening 12 having a diameter of not less than 80% of the liquid crystal cell pitch and not more than the liquid crystal cell pitch is provided in the substrate 11 that does not transmit illumination light.
[0042]
FIG. 4 is a diagram showing in detail the relative positional relationship between the circular aperture 12 of the aperture control plate 2 shown in FIG. 3 and the liquid crystal cell 10, in which 10 is an arbitrary liquid crystal cell having a square shape, 13, 14 , 15, 16 are square liquid crystal cells adjacent to the liquid crystal cell 10, and alternate long and short dash lines 17, 18 are center lines of boundaries between the arbitrary liquid crystal cell 10 and the adjacent liquid crystal cells 13, 14, 15, 16. The circular opening 12 may protrude from the liquid crystal cell 10 as shown in FIG. 4A, or may be accommodated in the liquid crystal cell 10 as shown in FIG.
[0043]
When the TFT 19 exists in the liquid crystal cell 10, as shown in FIG. 4C, the circular opening 12 is prevented from overlapping with the TFT 19 as much as possible. The center of the circular opening 12 is not necessarily coincident with the center of the liquid crystal cell 10.
[0044]
FIG. 5 shows an example of an opening shape other than a circle of the opening control plate 2 in which the liquid crystal cell pitch is equal in the x and y directions and the liquid crystal cell 10 is square. 5A is an example of an opening 20 having an arbitrary curve similar to a circle, FIG. 5B is an example of an opening 21 having chamfered corners of a square, and FIG. 4C is an example of a polygonal opening 22. FIG. 5D, FIG. 5E, and FIG. 5F are examples of the openings 23, 24, and 25 having arbitrary rounded corners of the polygonal openings.
[0045]
Note that the number of corners in the case of a polygonal opening or an opening in which a corner of a polygon is rounded may be arbitrary.
[0046]
Moreover, the curve for giving roundness does not necessarily need to be a circular arc, and may be arbitrary. The side and the curve forming the rounded corner may intersect or touch each other.
[0047]
The aperture control plate 2 may form a hole-like opening in a thin plate or thin film that does not transmit illumination light, and a light-shielding film is provided on a transmissive substrate such as glass or quartz that transmits the illumination light 4. You may remove in the shape of an opening.
[0048]
With the opening control plate 2 having an opening as shown in FIGS. 3, 4, and 5 inserted, the pattern designating unit 8 designates transmission and shading of each liquid crystal cell of the liquid crystal panel 1, and the illumination device 3 The illumination panel 4 illuminates the liquid crystal panel 1 to project a pattern shape designated by transmission and non-transmission of the liquid crystal cell 10 through the projection optical system 5 onto the substrate 6 to be exposed. The attached photosensitive material 7 is exposed.
[0049]
FIG. 6 is a diagram for explaining the liquid crystal matrix projection exposure method of the present invention, and illustrates the relationship between the designation of transmission and light shielding on the liquid crystal panel 1 and the transfer pattern on the substrate 6 to be exposed. For example, as shown in FIG. 6A, the first exposure is performed with the shaded portion as the light-shielding liquid crystal cell 26 and 27 as the transmissive liquid crystal cell in which the transmissive area is limited by the aperture control plate 2. The scale of the liquid crystal matrix is arbitrary, the x-axis and y-axis are taken as shown in the figure, and the distances from the y-axis and x-axis to the illustrated liquid crystal matrix are a and b, respectively.
[0050]
As shown in FIG. 6B, the photosensitive material 7 applied on the substrate 6 to be exposed is exposed to the extent that the exposed portions of the dotted or adjacent transmissive liquid crystal cells 27 slightly overlap each other. Reference numeral 28 denotes an exposed portion of the photosensitive material 7. How the exposed portions overlap and leave depends on the size, shape and exposure amount of the aperture of the aperture control plate 2, the type and thickness of the photosensitive material 7, and the like.
[0051]
In general, the exposure portion 28 of the photosensitive material 7 has a projection exposure magnification with respect to the transmissive liquid crystal cell 27 whose transmission region is limited by the aperture control plate 2, but it is difficult to understand the correspondence. In (b), the size of the exposed portion 28 of the photosensitive material 7 is drawn in accordance with the size of the transmissive liquid crystal cell 27 in which the transmissive region is limited by the aperture control plate 2.
[0052]
Next, the liquid crystal panel 1 is moved by ½ of the liquid crystal cell pitch p, or the exposed substrate 6 is moved by a distance corresponding to (½ of the liquid crystal cell pitch p) × (projection exposure magnification). The second exposure is performed by resetting the transmission and light shielding of the liquid crystal cell. For example, as shown in FIG. 6 (c), the liquid crystal panel 1 is moved in the y direction by ½ of the liquid crystal cell pitch p, the shaded portion is used as the light-shielded liquid crystal cell 29, and 30 is used as the transmission area by the aperture control plate 2. A second exposure is performed as a limited transmissive liquid crystal cell. As a result, reference numeral 31 in FIG. 6D becomes an exposed portion of the photosensitive material 7 by the second exposure. A portion 28 drawn in an overlapping manner is a portion exposed by the first exposure.
[0053]
Next, the liquid crystal panel 1 is moved by a half of the liquid crystal cell pitch p in the direction perpendicular to the second exposure with respect to the position for the first exposure or the substrate 6 to be exposed is ( The third exposure is performed by moving the distance corresponding to ½ of the liquid crystal cell pitch p) × (projection exposure magnification) and resetting the transmission and light shielding of the liquid crystal cell of the liquid crystal panel 1. For example, as shown in FIG. 5 (e), the liquid crystal panel 1 is now moved by ½ of the liquid crystal cell pitch p in the x direction, the shaded portion is used as the light-shielded liquid crystal cell 32, and 33 is transmitted through the aperture control plate 2. The third exposure is performed as a transmissive liquid crystal cell with a limited area. As a result, 34 in FIG. 6 (f) becomes an exposed portion of the photosensitive material 7 by the third exposure. An overlapping portion 35 is a portion exposed by the first exposure and the second exposure.
[0054]
Further, the liquid crystal panel 1 is 1 / of the liquid crystal cell pitch p in both the direction moved during the second exposure and the direction moved during the third exposure with respect to the position of the first exposure. Or the substrate 6 to be exposed is moved by a distance corresponding to (1/2 of the liquid crystal cell pitch p) × (projection exposure magnification) to reset the transmission and non-transmission of the liquid crystal cell of the liquid crystal panel 1. 4 exposure is performed. For example, as shown in FIG. 5 (g), the liquid crystal panel 1 is moved in the x direction and the y direction by ½ of the liquid crystal cell pitch p, the shaded portion is used as the light-shielded liquid crystal cell 36, and 37 is opened. The fourth exposure is performed as a transmissive liquid crystal cell in which the transmissive region is limited by the control plate 2. As a result, reference numeral 38 in FIG. 6H is an exposed portion of the photosensitive material 7 by the fourth exposure. Reference numeral 39 drawn in an overlapping manner is a portion exposed by the first exposure, the second exposure, and the third exposure.
[0055]
When the first exposure, the second exposure, the third exposure, and the fourth exposure are performed as described above, the photosensitive material 7 is exposed a plurality of times in a place where the exposure regions overlap.
[0056]
When performing exposure, the liquid crystal panel 1 or the substrate 6 to be exposed is moved by a predetermined distance, although not shown, the stage on which each is mounted may be moved.
[0057]
By the way, when the pattern is projected and exposed, the optical image of the pattern formed on the exposed substrate 6 by the projection optical system 5 is formed with a spread of intensity distribution with respect to the original pattern on the liquid crystal panel 1. .
[0058]
The spread of the intensity distribution of the pattern light image is mainly determined by the optical characteristics such as the numerical aperture and aberration of the projection optical system 5 and the illumination conditions such as the coherence coefficient of the illumination light 4 that illuminates the liquid crystal panel 1.
[0059]
As a result, the pattern size of the photosensitive material 7 obtained when developing after exposure is not always constant, and depends on the spread of the intensity distribution of the pattern light image formed on the exposed substrate 6 and the exposure amount. fluctuate.
[0060]
Accordingly, the shape and size of the pattern of the photosensitive material 7 exposed in the form of dots by each of the four exposures from the first exposure to the fourth exposure vary depending on the total exposure received at each location. The portions exposed by two or more exposures and their surroundings are affected by the exposure farther from the place where the exposure amount is exposed only once.
[0061]
For this reason, a part of the spot-like photosensitive portions are overlapped, and four exposures from the first exposure to the fourth exposure are performed as shown in FIG. 6, and the exposure corresponding to the size of the opening of the opening control plate 2 is performed. If the amount is selected, the overlapping portions of the patterns that form the valleys of the exposure area are overlapped with each other. Therefore, the light intensity distribution by each exposure is overlapped so that the light intensity at the place where the exposure is performed only once is set to the same level. Can do. That is, by connecting a part of the spot-like exposure portions in a superimposed manner, as shown in FIG. 7, it is possible to form a substantially smoothly continuous transfer pattern 40 similar to the envelope.
[0062]
At this time, there is a problem of how many times the circular fine exposure regions are overlapped and the exposure is repeated so that the pattern 40 is formed smoothly and continuously. However, the radius is generally circular or at intervals shorter than 1.2 times the radius. When exposed, the pattern is almost smooth. Accordingly, the exposure distance interval in the four exposures from the first exposure to the fourth exposure is the minimum appropriate interval. Even if exposure is performed at shorter intervals, the smoothness of the connection state is not improved so much, but the number of exposures increases, so the total required time becomes longer. On the other hand, when exposure is performed at longer distance intervals, pattern connection traces are likely to appear.
[0063]
In the portion where the first exposure and the fourth exposure overlap, the distance between the circular fine exposure regions is larger than when the exposure is overlapped in the x direction and the y direction. Although the unevenness remains, the oblique pattern is formed almost smoothly. As in the past, when the transmissive part is specified in the oblique direction on the liquid crystal panel 1, the corners of the rectangular exposed part are connected to each other, and a gap is not formed between the patterns, or a bill-like pattern is formed. However, the improvement is remarkable compared with it.
[0064]
Note that the exposure order of the four exposures from the first exposure to the fourth exposure is arbitrary, and the order shown in FIG. 5 is not necessarily required.
[0065]
Further, although the liquid crystal panel 1 or the exposed substrate 6 is moved in the + x or + y direction in FIG. 5, it may be moved in the −x or −y direction.
[0066]
When a large number of the same patterns are transferred onto the substrate 6 to be exposed, the four exposures from the first exposure to the fourth exposure may be sequentially repeated. , The second exposure is performed by changing the pattern on the liquid crystal panel 1, the third exposure is performed by changing the pattern on the liquid crystal panel 1 again, and finally the liquid crystal panel 1 is again performed. Exposure in which the pattern on the liquid crystal panel 1 is the same may be performed continuously, such as changing the upper pattern and performing the fourth exposure. Since the number of times of changing the pattern on the liquid crystal panel 1 is reduced, the time required for transferring the pattern can be shortened.
[0067]
The reason why the pattern can be formed almost smoothly is closely related to the shape of the opening of the opening control plate 2 shown in FIG. 5, and is a square or rectangle having sides in the vertical and horizontal directions as in the prior art. Even if a cell is exposed multiple times and a part is overlapped, it does not work.
[0068]
FIG. 8 shows an example in which a plurality of exposures are performed and a part of the cells is overlapped with a square cell as in the prior art. As shown in FIG. 8A, the first exposure is performed with the shaded portion as the light-shielded liquid crystal cell 41 and 42 as the transmissive liquid crystal cell. As shown in FIG. 8B, the photosensitive material 7 applied on the substrate 6 to be exposed is exposed to such an extent that the exposed portions of the dot-like or adjacent transmissive liquid crystal cells 42 slightly overlap each other. Reference numeral 43 denotes an exposed portion of the photosensitive material 7.
[0069]
In general, the exposure portion 43 of the photosensitive material 7 has a size obtained by multiplying the transmissive liquid crystal cell 42 by the projection exposure magnification. However, since the correspondence becomes difficult to understand, the exposure of the photosensitive material 7 is shown in FIG. The size of the portion 43 is drawn in accordance with the size of the transmissive liquid crystal cell 42.
[0070]
Next, as in the present invention, the liquid crystal panel 1 is moved by a half of the liquid crystal cell pitch p, or the exposed substrate 6 is moved by a distance corresponding to (1/2 of the liquid crystal cell pitch p) × (projection exposure magnification). Then, the second exposure is performed by resetting the transmission and non-transmission of the liquid crystal cell of the liquid crystal panel 1. For example, as shown in FIG. 8C, the liquid crystal panel 1 is moved by ½ of the liquid crystal cell pitch p in the y direction, the shaded portion is used as the light-shielding liquid crystal cell 44, and 45 is the transmissive liquid crystal cell. I do. As a result, 46 in FIG. 8D becomes an exposed portion of the photosensitive material 7 by the second exposure. An overlapped portion 43 is a portion exposed by the first exposure.
[0071]
However, in the state where the aperture control plate 2 is not attached as described above, since the exposure is performed twice over the entire liquid crystal cell width, the light intensity distribution spreads outside the place corresponding to the transmissive liquid crystal cell 45 of the substrate 6 to be exposed. A part is made. Accordingly, when the photosensitive material 6 is a positive type, a dent 48 is formed in the resist pattern 47 after development as shown in FIG. 9A, and when the photosensitive material 6 is a negative type, a protrusion is formed on the resist pattern 49 after development. 50 is made.
[0072]
The size of the aperture of the aperture control plate 2 may be smaller, and when m is an integer greater than 3, it is similar to a circle, oval or any straight line and / or curved circle or oval In the shape, the diameter, the opposite side length, or the diagonal length of the opening in the x and y directions may be set to 2 / m of the liquid crystal cell pitch or a range of −20% to + 20% thereof, respectively.
[0073]
FIG. 10 shows an embodiment where m = 3. The figure shows a situation where the photosensitive material 7 is sequentially exposed by a plurality of exposures. The shape of the opening may be the same as in FIG.
[0074]
In this embodiment, first, the size of the opening, the diameter or the opposite side length or the diagonal length in the x and y directions of the opening of the opening control plate 2 is set to 2/3 of the liquid crystal cell pitch p or -20% to + 20% thereof. By setting the transmission and shading of the liquid crystal cell of the liquid crystal panel 1 to be within the range, and performing the first exposure, dots are exposed at intervals corresponding to the liquid crystal cell pitch p as shown in FIG. .
[0075]
Reference numeral 51 denotes an exposed portion of the photosensitive material 7 on the exposed substrate 6. The exposure unit 51 has a size obtained by multiplying the size of the aperture of the aperture control plate 2 by the projection exposure magnification.
[0076]
Next, the liquid crystal panel 1 is moved in the x or y direction by 1/3 of the liquid crystal cell pitch p, or the exposed substrate 6 is moved by a distance corresponding to (1/3 of the liquid crystal cell pitch p) × (projection exposure magnification). The second exposure is performed as shown in FIG. 10B by moving and resetting the transmission and light shielding of the liquid crystal cell of the liquid crystal panel 1. Reference numeral 52 denotes an exposure portion by the second exposure. Here, the case where the liquid crystal panel 1 is moved in the y direction is shown as an example.
[0077]
Further, the liquid crystal panel 1 is moved 2/3 of the liquid crystal cell pitch in the y direction with respect to the position where the first exposure is performed, or the substrate 6 to be exposed is moved in the y direction (2/3 of the liquid crystal cell pitch) × (projection exposure magnification). ), The third exposure is performed by setting the transmission and shading of the cells of the liquid crystal panel 1 again. In FIG. 10C, reference numeral 53 denotes an exposure unit by the third exposure, and 54 denotes an exposure unit by the first exposure and the second exposure.
[0078]
Next, the liquid crystal panel 1 is moved 1/3 of the liquid crystal cell pitch in the x direction with respect to the position where the first exposure is performed, or the substrate 6 to be exposed is moved in the x direction (1/3 of the liquid crystal cell pitch) × (projection exposure). The fourth exposure is performed by moving a distance corresponding to (magnification) and resetting the transmission and shading of the cells of the liquid crystal panel 1. In FIG. 10D, reference numeral 55 denotes an exposure unit by the fourth exposure, and reference numeral 56 denotes an exposure unit by any one of the exposure from the first exposure to the third exposure.
[0079]
Further, the liquid crystal panel 1 is moved 2/3 of the liquid crystal cell pitch in the x direction with respect to the position where the first exposure is performed, or the substrate 6 to be exposed is moved in the x direction (2/3 of the liquid crystal cell pitch) × (projection exposure magnification). ), The fifth exposure is performed by resetting the transmission and shading of the cells of the liquid crystal panel 1. In FIG. 10 (e), 57 is an exposure unit by the fifth exposure, and 58 is an exposure unit by any one of the exposure from the first exposure to the fourth exposure.
[0080]
Next, the liquid crystal panel 1 is moved 1/3 of the liquid crystal cell pitch in the x direction and 2/3 of the liquid crystal cell pitch in the y direction with respect to the position where the first exposure has been performed, or the exposed substrate 6 is moved in the x direction (liquid crystal Move the cell by a distance corresponding to (1/3 of the cell pitch) x (projection exposure magnification) and (2/3 of the liquid crystal cell pitch) x (projection exposure magnification) in the y direction, and reset the transmission and shading of the cells on the liquid crystal panel 1 Then, a sixth exposure is performed. In FIG. 10 (f), 59 is an exposure unit by the sixth exposure, and 60 is an exposure unit by any one of the exposure from the first exposure to the fifth exposure.
[0081]
Further, the liquid crystal panel 1 is moved 2/3 of the liquid crystal cell pitch in the x direction and 1/3 of the liquid crystal cell pitch in the y direction with respect to the position where the first exposure is performed, or the exposed substrate 6 is moved in the x direction (liquid crystal cell pitch). 2/3) × (projection exposure magnification), move in the y direction by a distance corresponding to (1/3 of the liquid crystal cell pitch) × (projection exposure magnification), and reset the transmission and shading of the liquid crystal panel 1 cells. A seventh exposure is performed. In FIG. 10G, reference numeral 61 denotes an exposure part by the seventh exposure, and 62 denotes an exposure part by any one of the exposure from the first exposure to the sixth exposure.
[0082]
FIG. 8 shows only the seventh exposure described above, but if necessary, the liquid crystal panel 1 is 1/3 of the liquid crystal cell pitch in the x direction with respect to the position where the first exposure is performed, y Move the liquid crystal cell pitch in the direction by 1/3 or move the exposed substrate 6 in the x direction (1/3 of the liquid crystal cell pitch) × (projection exposure magnification) and in the y direction (1/3 of the liquid crystal cell pitch) × (projection exposure magnification) ) Is moved by a distance corresponding to (8), and transmission and shading of the cells of the liquid crystal panel 1 are reset and the eighth exposure is performed.
[0083]
If necessary, the liquid crystal panel 1 is moved 2/3 of the liquid crystal cell pitch in the x direction and 2/3 of the liquid crystal cell pitch in the y direction with respect to the position where the first exposure is performed, or the exposed substrate 6 is moved x Move by a distance corresponding to (2/3 of the liquid crystal cell pitch) × (projection exposure magnification) in the direction and (2/3 of the liquid crystal cell pitch) × (projection exposure magnification) in the y direction, and transmit and block the cells of the liquid crystal panel 1 Is reset and the ninth exposure is performed.
[0084]
In addition to the eighth exposure and the ninth exposure, each exposure may be omitted according to the desired pattern shape.
[0085]
In addition, the exposure order of the exposure performed a plurality of times is arbitrary, and the order shown in FIG. 10 is not necessarily required.
[0086]
Further, although the liquid crystal panel 1 or the substrate 6 to be exposed is moved in the + x or + y direction in FIG. 8, it may be moved in the −x or −y direction.
[0087]
If an exposure amount corresponding to the size of the aperture of the aperture control plate 2 is selected by these multiple exposures, as in the case of FIG. 5, the overlapping portions of the patterns that form the valleys of the exposure region overlap. By superimposing the spread of the light intensity distribution due to each exposure, it is possible to make the light intensity the same as the place where the light is exposed only once. That is, by connecting a part of the spot-like exposure portions in a superimposed manner, as shown in FIG. 11, a substantially smooth and continuous pattern 63 similar to the envelope can be formed.
[0088]
When m ≧ 4, when n is 0 or a positive integer smaller than m, move n / m of the liquid crystal cell pitch p in the x and / or y direction with respect to the first exposure position, or The substrate 6 to be exposed is moved by a distance corresponding to (cell pitch n / m) × (projection exposure magnification) to reset the transmission and shading of the cells of the liquid crystal panel 1 and perform exposure one after another.
[0089]
The plurality of exposures may be performed in any order.
[0090]
When exposed in this manner, the photosensitive material 7 on the substrate 6 to be exposed has a shape that envelops all of the portions exposed in a dot-like manner by a plurality of exposures, as shown in FIGS. To be exposed.
[0091]
Therefore, the pattern of the photosensitive material 6 formed after development has a smooth outer shape in which the unevenness corresponding to the joints of the exposed portions is smoothed.
[0092]
The smoothness of the pattern side wall including the cases of FIGS. 6 and 10 is not limited to the shape and size of the opening of the opening control plate 2, the type and thickness of the photosensitive material 7, and the numerical aperture of the projection optical system 5. Depending on the exposure wavelength of the illumination light 4, the degree of coherence, and the like, if the exposure amount is selected, the circle and the polygon are connected and smoothness that cannot be considered as being exposed.
[0093]
Further, even when the exposure amount is not optimal, there is only a deterioration in the pattern due to the liquid crystal cell boundary and the portion corresponding to the TFT as compared with the case where the transfer pattern is connected in units of the entire liquid crystal cell in the conventional projection exposure apparatus and method. Therefore, a pattern having a remarkably smooth outer shape can be obtained.
[0094]
The aperture diameter of the aperture control plate 2 or the opposite side length or diagonal length in the x and y directions is 2 / m of the liquid crystal cell pitch or a range of −20% to + 20% when m is an integer of 3 or more. If it is set within the range, a conventional fine pattern of about 2 / m can be formed as (approximately 2 / m of the liquid crystal cell pitch p) × (projection exposure magnification).
[0095]
Further, exposure is performed by moving the liquid crystal panel 1 by a pattern of (approximately 1 / m of the liquid crystal cell pitch p) (approximately 1 / m of the liquid crystal cell pitch p) (approximately 1 / m of the liquid crystal cell pitch p) x (projection exposure magnification). / M) × (projection exposure magnification) by moving the exposed substrate 6 and performing exposure, it is possible to form a pattern having a fine pitch of 2 / m of the pattern that has been conventionally transferred.
[0096]
FIG. 12 shows, as an example, an example in which a pattern having a 2/3 line width and a 2/3 pitch can be formed by the method shown in FIG. 10 when m = 3. FIG. 12A shows the overlap of exposure locations, and 64 is an exposure location corresponding to one opening of the aperture control plate 2. FIG. 12B shows the pattern shape of the photosensitive material 7 obtained after development. The figure shows the case where a positive resist is used as the photosensitive material 7, wherein 65 is a resist and 66 is a pattern formed by removing the resist after development.
[0097]
In the above description, the liquid crystal cell pitch is assumed to be equal in the x direction and the y direction. However, it is clear that the present invention is effective even if the liquid crystal cell pitch is not necessarily equal in the x direction and the y direction.
[0098]
For example, when the liquid crystal cell has a vertically long liquid crystal and the liquid crystal cell pitch in the y direction is longer than the liquid crystal cell pitch in the x direction, the shape of the opening of the opening control plate 2 may be a shape as illustrated in FIG.
13A is an oval opening 67 made of an arbitrary curve, FIGS. 13B and 13C are polygonal openings 68 and 69, FIG. 13D, FIG. 13E and FIG. (F) is a shape 70, 71, 72 with rounded corners of the polygon. The size of the opening and the distance to move the liquid crystal panel 1 and the substrate 6 to be exposed at the time of exposure may be determined based on the liquid crystal cell pitch in each direction separately for the x direction and the y direction.
[0099]
By the way, when a pattern is formed by superposing a plurality of exposures as described above according to the present invention, the time required for pattern formation becomes longer depending on the number of exposures. Therefore, it is more convenient to configure so that the opening control plate 2 having an appropriately sized opening can be attached as necessary.
[0100]
FIG. 14 shows a liquid crystal matrix projection exposure apparatus of the present invention provided with a retracting / entry mechanism for attaching / detaching the aperture control plate 2. The carriage 74 on which the aperture control plate 2 is mounted moves on the guide mechanism 73, and the aperture control plate 2 in the retracted position indicated by the solid line in the figure is carried into the use position 75 indicated by the two-dot chain line.
[0101]
When the transferred pattern may have some dents or protrusions, the opening control plate 2 is retracted, and the opening control plate 2 is mounted when a smooth pattern is required.
[0102]
A retracting / entering mechanism for attaching and detaching the opening control plate 2 may be arbitrary, and a retracting / entering mechanism using a rotating arm may be provided as shown in FIG. .
[0103]
FIG. 15 shows a liquid crystal matrix projection exposure apparatus in which a plurality of aperture control plates can be replaced. A plurality of opening control plates are prepared in the opening control plate stocker 76. In the figure, three aperture control plates indicated by 77, 78, and 79 are drawn, but the number of stocks is arbitrary.
[0104]
A rotary arm 81 that rotates and moves up and down while holding the aperture control plate on the rotary column 80 is attached, and a required aperture control plate is selected and mounted on the liquid crystal panel 1.
[0105]
Also in this case, the retracting / entry mechanism for attaching and detaching the opening control plate may be arbitrary, and as shown in FIG. 14, the carriage on which the opening control plates 77, 78, and 79 are moved on the guide mechanism, or the telescopic mechanism You may use an arm to do. In addition, 82 shown with the dashed-two dotted line has shown the use position of the opening control board.
[0106]
【The invention's effect】
As described above, according to the liquid crystal matrix projection exposure apparatus and the liquid crystal matrix projection exposure method of the present invention, even if there is a boundary between the liquid crystal cells where the exposure light beam is not transmitted, Even if a TFT that does not transmit exposure light is provided, it is possible to transfer and form a pattern having a smooth outer shape that is not conspicuously connected.
[0107]
Also, the oblique line pattern can be transferred and formed much more smoothly than before.
[0108]
Furthermore, by reducing the size of the aperture of the aperture control plate, even if the liquid crystal cell size and the liquid crystal cell pitch of the liquid crystal panel to be specified are the same, it is possible to transfer a finer pattern and a pattern with a smaller pattern pitch than the conventional one. it can.
A pattern having a smaller pattern pitch than the conventional one can be transferred.
[0109]
Note that by reducing the size of the aperture of the aperture control plate, a plurality of exposures are required. However, since exposure is performed at a distance interval of an integral number of the liquid crystal cell pitch, an increase in the number of exposures is the minimum necessary. Number of times.
[Brief description of the drawings]
FIG. 1 is a block diagram of a liquid crystal matrix projection exposure apparatus of the present invention.
FIG. 2 is another block diagram of the liquid crystal matrix projection exposure apparatus of the present invention.
FIG. 3 is a relationship between a cell arrangement of a liquid crystal panel and an opening of an opening control plate.
FIG. 4 is a detailed view of the positional relationship between the liquid crystal cell and the opening of the opening control plate.
FIG. 5 is an example of an opening shape of an opening control plate for a square liquid crystal cell.
FIG. 6 is an explanatory diagram of a liquid crystal matrix projection exposure method of the present invention.
7 is a pattern shape transferred by the method of the present invention shown in FIG.
FIG. 8 shows an exposure state when connection exposure is performed without using an aperture control plate.
FIG. 9 shows a transfer pattern shape when connection exposure is performed without using an aperture control plate.
FIG. 10 is an explanatory diagram of another liquid crystal matrix projection exposure method of the present invention.
11 is a pattern shape transferred by the method of the present invention shown in FIG.
FIG. 12 is an explanatory diagram of an example in which a pattern with a fine width and a fine pitch can be formed.
FIG. 13 is an example of an opening shape of an opening control plate for liquid crystal cells having different liquid crystal cell pitches in the x and y directions.
FIG. 14 is a block diagram of a liquid crystal matrix projection exposure apparatus of the present invention provided with a retracting / entry mechanism for attaching and detaching an aperture control plate.
FIG. 15 is a block diagram of a liquid crystal matrix projection exposure apparatus of the present invention in which a plurality of aperture control plates can be replaced.
FIG. 16 is a block diagram of a projection exposure apparatus using a conventional original drawing substrate.
FIG. 17 is a block diagram of a conventional liquid crystal matrix projection exposure apparatus.
18 is a schematic diagram of the liquid crystal panel 1. FIG.
FIG. 19 is an explanatory diagram of a pattern shape formed by a conventional liquid crystal matrix projection exposure apparatus.
[Explanation of symbols]
1 LCD panel
2 Opening control plate
3 Lighting equipment
4 Illumination light
5 Projection optical system
6 Substrate to be exposed
7 Photosensitive material
8 Pattern specification part
10 Liquid crystal cell
20, 21, 22, 23, 24, 25 Opening shape examples
26 29, 32, 36 Light-shielding liquid crystal cell
27, 30, 33, 37 Transmission liquid crystal cell
28, 31, 34, 35, 38, 39 Exposure part
40 Transcription pattern
73 Guide mechanism
74 Carriage
76 Opening control plate stocker
80 Rotating prop
81 Rotating arm

Claims

Liquid crystal matrix projection having a liquid crystal panel designating a pattern shape as a transmission part or non-transmission part, an illuminating device for illuminating the liquid crystal panel, and a projection optical system for projecting the pattern designated by the liquid crystal panel onto a substrate to be exposed In the exposure apparatus,
Similar to a circle, oval, or a circle or oval with a circular shape, an oval shape, or an arbitrary straight line and / or a curved line, which is close to or in close contact with the liquid crystal panel and restricts the transmission region of the liquid crystal cell of the liquid crystal panel to only a part. An aperture control plate having an aperture of the shape corresponding to all the liquid crystal cells is provided ,
The substrate to be exposed is projected and exposed as the first exposure to the extent that the exposed portions of the dotted or adjacent liquid crystal cells that are the transmission portions on the liquid crystal panel slightly overlap with each other through the aperture control plate. ,
The liquid crystal panel is moved with respect to the position of the liquid crystal panel at the time of the first exposure, or the position of the substrate to be exposed is moved with respect to the position of the substrate to be exposed at the time of the first exposure, and a pattern shape is formed on the liquid crystal panel. A liquid crystal matrix projection exposure apparatus characterized in that the substrate to be exposed is projected and exposed to the specified pattern shape through the aperture control plate.

2. A liquid crystal matrix projection exposure apparatus according to claim 1, wherein the aperture control plate has a diameter or opposite side length or diagonal length in the x and y directions of 80% or more of the liquid crystal cell pitch and less than or equal to the liquid crystal cell pitch in each of the x and y directions. A liquid crystal matrix projection exposure apparatus comprising:

2. The liquid crystal matrix projection exposure apparatus according to claim 1, wherein when m is an integer of 3 or more, the diameter or opposite side length or diagonal length of the aperture in the x and y directions is 2 of the liquid crystal cell pitch in each of the x and y directions. / M or a liquid crystal matrix projection exposure apparatus having an aperture control plate set in the range of -20% to + 20%

Liquid crystal matrix projection having a liquid crystal panel designating a pattern shape as a transmission part or non-transmission part, an illuminating device for illuminating the liquid crystal panel, and a projection optical system for projecting the pattern designated by the liquid crystal panel onto a substrate to be exposed In the exposure apparatus,
Similar to a circle, oval, or a circle or oval with a circular shape, an oval shape, or an arbitrary straight line and / or a curved line, which is close to or in close contact with the liquid crystal panel and restricts the transmission region of the liquid crystal cell of the liquid crystal panel to only a part. An aperture control plate having an aperture of the shape corresponding to all the liquid crystal cells is provided,
The substrate to be exposed is projected and exposed as the first exposure to the extent that the exposed portions of the dotted or adjacent liquid crystal cells that are the transmission portions on the liquid crystal panel slightly overlap with each other through the aperture control plate. ,
The liquid crystal panel is moved with respect to the position of the liquid crystal panel at the time of the first exposure, or the position of the substrate to be exposed is moved with respect to the position of the substrate to be exposed at the time of the first exposure, and a pattern shape is formed on the liquid crystal panel. Is designated as a transmissive part or a light-shielding part, and the substrate to be exposed is projected and exposed to the designated pattern shape through the opening control plate,
A liquid crystal matrix projection exposure apparatus having a retract / entry mechanism for attaching and detaching the aperture control plate

Liquid crystal matrix projection having a liquid crystal panel designating a pattern shape as a transmission part or non-transmission part, an illuminating device for illuminating the liquid crystal panel, and a projection optical system for projecting the pattern designated by the liquid crystal panel onto a substrate to be exposed In the exposure apparatus,
Similar to a circle, oval, or a circle or oval with a circular shape, an oval shape, or an arbitrary straight line and / or a curved line, which is close to or in close contact with the liquid crystal panel and restricts the transmission region of the liquid crystal cell of the liquid crystal panel to only a part. A plurality of aperture control plates having apertures in the shape corresponding to all the liquid crystal cells are provided with different shapes and / or dimensions of the apertures,
The substrate to be exposed is projected and exposed as the first exposure to the extent that the exposed portions of the dotted or adjacent liquid crystal cells that are the transmission portions on the liquid crystal panel slightly overlap with each other through the aperture control plate. ,
The liquid crystal panel is moved with respect to the position of the liquid crystal panel at the time of the first exposure, or the position of the substrate to be exposed is moved with respect to the position of the substrate to be exposed at the time of the first exposure, and a pattern shape is formed on the liquid crystal panel. Is designated as a transmissive part or a light-shielding part, and the substrate to be exposed is projected and exposed to the designated pattern shape through the opening control plate,
A liquid crystal matrix projection exposure apparatus having a mechanism for selecting and attaching / detaching an arbitrary aperture control plate.

The transmissive region of the liquid crystal cell in the liquid crystal panel has a circular shape, an oval shape, a circular shape constituted by an arbitrary straight line and / or curved line, a shape similar to an elliptical shape, a diameter in the x and y directions, or an opposite side length or diagonal. The length is limited by an aperture control plate having an opening corresponding to all the liquid crystal cells with a length of 80% or more of the liquid crystal cell pitch and less than or equal to the liquid crystal cell pitch in each of the x and y directions. Leave,
A first step of designating a pattern shape on the liquid crystal panel as a transmissive portion or a light shielding portion, and projecting and exposing the substrate to be exposed to the designated pattern shape while passing through the opening of the opening control plate ;
The position of the liquid crystal panel is moved in the x direction by ½ of the x direction pitch of the liquid crystal cell with respect to the position of the liquid crystal panel or the substrate to be exposed in the first step, or (Liquid crystal cell pitch) x (projection exposure magnification) ½, move in the x direction,
A second step of re-designating the pattern shape on the liquid crystal panel as a transmission part or a light-shielding part, and projecting and exposing the substrate to be exposed to the designated pattern shape while passing through the opening of the opening control plate ;
The position of the liquid crystal panel is moved in the y direction by a half of the y direction pitch of the liquid crystal cell with respect to the position of the liquid crystal panel or the exposed substrate in the first step, or the position of the exposed substrate is changed to the y direction (y direction). (Liquid crystal cell pitch) x (projection exposure magnification) ½ in the y direction,
A third step of re-designating the pattern shape on the liquid crystal panel as a transmissive portion or a light-shielding portion, and projecting and exposing the substrate to be exposed to the designated pattern shape while passing through the opening of the opening control plate ;
With respect to the position of the liquid crystal panel or the substrate to be exposed in the first step, the position of the liquid crystal panel is set to the x direction pitch of the liquid crystal cell with respect to the position of the liquid crystal panel or the substrate to be exposed in the first step. Move the half of the y-direction pitch of the liquid crystal cell in the 1/2 and y directions, or move the position of the substrate to be exposed in the x direction (x direction liquid crystal cell pitch) × 1/2 (projection exposure magnification), y direction (X-direction liquid crystal cell pitch) x (projection exposure magnification) ½,
And a fourth step of re-designating the pattern shape on the liquid crystal panel as a transmissive portion or a light-shielding portion, and projecting and exposing the substrate to be exposed to the designated pattern shape while passing through the opening of the opening control plate. Liquid crystal matrix projection exposure method characterized

When the transmission region of the liquid crystal cell in the liquid crystal panel has a circular shape, an oval shape, a circular shape constituted by an arbitrary straight line and / or curved line, or a shape similar to an oval, and m is an integer of 3 or more, x, An aperture control plate having openings corresponding to all liquid crystal cells, with the diameter or opposite side length or diagonal length of the opening in the y direction being set to 2 / m of the liquid crystal cell pitch or a range of -20% to + 20% thereof, respectively. Limit and leave only a part of each liquid crystal cell as a transmission part,
A first step of designating a pattern shape on the liquid crystal panel as a transmissive portion or a light shielding portion, and projecting and exposing the substrate to be exposed to the designated pattern shape while passing through the opening of the opening control plate ;
When n is an arbitrary positive integer smaller than 0 or m with respect to the position of the liquid crystal panel or the substrate to be exposed in the first step, the position of the liquid crystal panel is set to x with respect to the first exposure position. Move the liquid crystal cell pitch n / m in the direction and / or y direction, or move the substrate to be exposed by a distance corresponding to (cell pitch n / m) × (projection exposure magnification),
And a step of re-designating the pattern shape on the liquid crystal panel as a transmissive portion or a light-shielding portion, and projecting and exposing the substrate to be exposed to the designated pattern shape while passing through the opening of the opening control plate. Liquid crystal matrix projection exposure method