JP4123801B2 - Electro-optical device manufacturing method, electro-optical device manufacturing apparatus, electro-optical device, and electronic apparatus - Google Patents

Description

【００５５】
【化２】

【００５６】
【化３】

【００５７】
【化４】

【００５８】
【化５】

【００５９】
陰極１５４は、発光部１４０の全面に形成されており、画素電極１４１と対になって機能層２９０に電流を流す役割を果たす。この陰極１５４は、例えば、カルシウム層とアルミニウム層とが積層されて構成されている。このとき、発光層に近い側の陰極には仕事関数が低いものを設けることが好ましく、特にこの形態においては発光層２９０ｂに直接に接して発光層２９０ｂに電子を注入する役割を果たす。また、フッ化リチウムは発光層の材料によっては効率よく発光させるために、発光層２９０ｂと陰極１５４との間にＬｉＦを形成する場合もある。
なお、赤色及び緑色の発光層２９０ｂ1、２９０ｂ2にはフッ化リチウムに限らず、他の材料を用いてもよい。従ってこの場合は青色（Ｂ）発光層２９０ｂ3のみにフッ化リチウムからなる層を形成し、他の赤色及び緑色の発光層２９０ｂ1、２９０ｂ2にはフッ化リチウム以外のものを積層してもよい。また、赤色及び緑色の発光層２９０ｂ1、２９０ｂ2上にはフッ化リチウムを形成せず、カルシウムのみを形成してもよい。この場合、フッ化リチウムの厚さは、例えば２〜５ｎｍの範囲が好ましく、特に２ｎｍ程度がよい。またカルシウムのの厚さは、例えば２〜５０ｎｍの範囲が好ましい。
また、陰極１５４を形成するアルミニウムは、発光層２９０ｂから発した光を基板１２１側に反射させるもので、Ａｌ膜の他、Ａｇ膜、ＡｌとＡｇの積層膜等からなることが好ましい。また、その厚さは、例えば１００〜１０００ｎｍの範囲が好ましく、特に２００ｎｍ程度がよい。さらにアルミニウム上にＳｉＯ、ＳｉＯ2、ＳｉＮ等からなる酸化防止用の保護層を設けてもよい。
【００６０】
次に、上記有機ＥＬ素子（及び有機ＥＬ表示装置）の製造方法の一例について、特に、（１）プラズマ処理工程、（２）正孔注入／輸送層形成工程、（３）発光層形成工程、（４）対向電極（陰極）形成工程について、図７〜図１７を参照しながら、詳しく説明する。
【００６１】
（１）プラズマ処理工程
プラズマ処理工程には、回路素子としての薄膜トランジスタ１４３、画素電極１４１、及びバンク２８１が形成された基板１２１が投入される。プラズマ処理工程は、画素電極１４１の表面を活性化すること、バンク２８１の表面を表面処理することなどを目的としており、画素電極１４１の表面の親液化処理や、バンク２８１表面の撥液化処理を行う。
【００６２】
プラズマ処理工程は、（ａ）予備加熱工程、（ｂ）活性化工程（親液化工程）、（ｃ）撥液化工程、及び（ｄ）冷却工程に大別される。なお、これに限らず、必要に応じて工程を追加あるいは削除してもよい。
【００６３】
図７は、プラズマ処理工程で用いられるプラズマ処理装置の構成例を模式的に示している。プラズマ処理装置５０は、予備加熱処理室５１、第１プラズマ処理室５２、第２プラズマ処理室５３、冷却処理室５４、及びこれらの各処理室５１〜５４に基板を搬送する搬送装置５５を含む。本例では、各処理室５１〜５４は、搬送装置５５を中心として放射状に配置されている。
【００６４】
プラズマ処理装置では、まず、予備加熱処理室５１において基板の予備加熱を行い、次に、第１，第２プラズマ処理室５２，５３において、活性化処理及び撥液化処理を行う。撥液化処理の後、基板を冷却処理室５４に搬送し、基板を室温まで冷却する。以下、各処理について詳細に説明する。
【００６５】
（ａ）予備加熱工程
予備加熱工程では、予備加熱処理室５１において、バンクを含む基板を所定の温度に加熱する。加熱温度は、次工程であるプラズマ処理の処理温度と同程度に設定され、例えば７０〜８０℃である。予備加熱は、次のプラズマ処理において、基板の温度変動を抑制し、処理の均一性を高めることを主な目的としている。加熱手段としては、例えば、基板が搭載されるプレート（ステージ）にヒータが内蔵された構成のものが用いられる。
【００６６】
（ｂ）活性化工程
活性化工程では、基板に対して、大気雰囲気中で酸素を処理ガスとしてプラズマ処理（Ｏ2プラズマ処理）を行う。Ｏ2プラズマ処理は、画素電極の仕事関数の調整及び制御、画素電極表面の洗浄、及び画素電極表面の親液化などを目的としている。また、Ｏ2プラズマ処理により、画素電極とともにバンク表面が親液化され、次の撥液化工程において、バンクの撥液化が促進される。
【００６７】
図８は、第１プラズマ処理装置５２の要部構成を模式的に示した図である。図８において、バンクを含む基板１２１は加熱ヒータ内臓の試料ステージ５６上に載置され、基板１２１の上側には所定のギャップ間隔（例えば０．５〜２ｍｍ程度）の距離をおいてプラズマ放電電極５７が基板１２１に対向して配置される。基板１２１は、試料ステージ５６によって加熱されるとともに、試料ステージ５６を介して図示矢印方向に所定の搬送速度で搬送される。この搬送中、基板１２１に対してプラズマ状態の酸素が照射される。
【００６８】
Ｏ2プラズマ処理の処理条件は、例えば、プラズマパワー１００〜８００ｋＷ、酸素ガス流量５０〜１００ｍｌ/ｍｉｎ、搬送速度０．５〜１０ｍｍ／ｓｅｃ、基板温度７０〜９０℃である。なお、試料ステージ５６の加熱は、主として予備加熱された基板の保温のために行われる。また、処理雰囲気は、大気雰囲気に限らず、例えば真空下としてもよい。
【００６９】
Ｏ2プラズマ処理により、図９に示すように、画素電極１４１の電極面、バンク２８１の壁面及び上面が親液処理される。つまり、これらの各面に水酸基が導入されて親液性が付与される。図９では、親液処理された部分を一点鎖線で示している。なお、このＯ2プラズマ処理により、上述した画素電極の洗浄、仕事関数の調整も行われる。
【００７０】
（ｃ）撥液処理工程
撥液化工程では、基板に対して、大気雰囲気中でテトラフルオロメタンを処理ガスとするプラズマ処理（ＣＦ4プラズマ処理）を行う。第２プラズマ処理室５３（図７参照）の要部構成は、図８に示した第１プラズマ処理室５２とほぼ同じである。すなわち、試料ステージによって基板が加熱及び搬送され、基板に対してプラズマ状態のテトラフルオロメタン（四フッ化炭素）が照射される。
【００７１】
ＣＦ4プラズマ処理の処理条件は、例えば、プラズマパワー１００〜８００ｋＷ、４フッ化メタンガス流量５０〜１００ｍｌ/ｍｉｎ、基板搬送速度０．５〜１０ｍｍ／ｓｅｃ、基板温度７０〜９０℃である。他の処理条件が一定のとき、基板の搬送速度を変化させることにより、プラズマ処理の処理時間を変化させることができる。本例では、正孔注入／輸送層を形成するための液体材料（後述する第１組成物）に対するバンク表面の動的接触角を指標として、プラズマ処理の処理時間を管理する。
【００７２】
具体的には、上記液体材料に対するバンク表面の動的接触角としての後退接触角が２９°〜４５°の範囲内になるように、上記処理時間を管理する。上記後退接触角の目標値は、正孔注入／輸送層の平坦化に最適となるように予め求められたものである。バンク表面の後退接触角が２９°未満だと、撥液性が不十分となり、正孔注入／輸送層のバンク近傍の膜厚が厚くなるので好ましくない。また、後退接触角が４５°を超えると、撥液性が高くなりすぎて、正孔注入／輸送層のバンク近傍の膜厚が薄くなるので好ましくない。なお、試料ステージの加熱は、第１プラズマ処理室と同様に、主として予備加熱された基板の保温のために行われる。また、処理ガスは、テトラフルオロメタン（四フッ化炭素）に限らず、他のフルオロカーボン系のガスを用いてもよい。また、処理雰囲気は、大気雰囲気に限らず、例えば真空下としてもよい。
【００７３】
ＣＦ4プラズマ処理により、図１０に示すように、バンク２８１の壁面及び上面が撥液処理される。つまり、これらの各面にフッ素基が導入されて撥液性が付与される。図１０では、撥液性を示す領域を二点鎖線で示している。バンク２８１を構成するアクリル樹脂、ポリイミド樹脂等の有機物はプラズマ状態のフルオロカーボンが照射することで容易に撥液化する。また、この撥液化の前に、Ｏ2プラズマに親液化処理するとフッ素化されやすい、という特徴を有している。
なお、画素電極１４１の電極面もこのＣＦ4プラズマ処理の影響を多少受けるが、濡れ性に影響を与える事は少ない。図１０では、親液性を示す領域を一点鎖線で示している。
【００７４】
（ｄ）冷却工程
冷却工程では、冷却処理室５４（図７参照）において、プラズマ処理後の基板を所定の温度まで冷却する。基板の冷却は、次の正孔注入／輸送層形成工程において、基板の温度変動を抑制し、処理の均一性を高めることを主な目的としており、室温あるいは正孔注入／輸送層形成工程における所定の管理温度まで基板を冷却する。冷却手段としては、例えば、基板が搭載されるプレート（ステージ）に冷却装置が内蔵された構成のものが用いられる。
【００７５】
（２）正孔注入／輸送層形成工程
次に、正孔注入／輸送層形成工程では、液滴吐出法（インクジェット法）を用いることにより、正孔注入／輸送層の形成材料を含む第１組成物を画素電極１４１上に吐出する。その後、乾燥処理及び熱処理を行い、画素電極１４１上に正孔注入／輸送層を形成する。
この正孔注入／輸送層形成工程を含めこれ以降の工程は、水、酸素の無い雰囲気とするのが好ましい。例えば、窒素雰囲気、アルゴン雰囲気等の不活性ガス雰囲気で行うことが好ましい。
【００７６】
インクジェット法による層の形成方法は以下の通りである。
図１１に示すように、画素電極１４１の周囲には画素領域１０２を区画するバンク２８１が形成されており、このバンク２８１の開口位置にインクジェットヘッドＨ１の吐出ノズルＨ２を配置する。そして、インクジェットヘッドＨ１と基板１２１とを相対的に移動させながら、吐出ノズルＨ２から１滴当たりの液量が制御された第１組成物の液滴を画素電極１４１上に吐出する。
【００７７】
吐出された第１組成物の液滴は、親液処理された画素電極１４１の電極面上に広がり、バンク２８１間に充填される。本例では、バンク２８１表面（壁面及び上面）が撥液性に加工されているので、仮に、第１組成物が所定の吐出位置から外れてバンク２８１の上面に吐出されたとしても、その上面で第１組成物の液滴がはじかれ、バンク２８１間に転がり込む。
【００７８】
液滴吐出用の装置として、本例では、上述した電気機械変換方式（ピエゾ方式）を用いた膜形成装置が用いられる。図１２は、ピエゾ方式による液体材料の吐出原理を説明するための図である。図１１において、液体材料を収容する液体室３２０に隣接してピエゾ素子３２１が設置されている。液体室３２０には、液体材料を収容する材料タンクを含む液体材料供給系３２２を介して液体材料が供給される。ピエゾ素子３２１は駆動回路３２３に接続されており、この駆動回路３２３を介してピエゾ素子３２１に電圧を印加し、ピエゾ素子３２１を変形させることにより、液体室３２０が変形し、ノズル３２４から液体材料が吐出される。この場合、印加電圧の値を変化させることにより、ピエゾ素子３２１の歪み量が制御される。また、印加電圧の周波数を変化させることにより、ピエゾ素子３２１の歪み速度が制御される。ピエゾ方式による液滴吐出は材料に熱を加えないため、材料の組成に影響を与えにくいという利点を有する。
【００７９】
上記第１組成物としては、例えば、ポリエチレンジオキシチオフェン（ＰＥＤＯＴ）等のポリチオフェン誘導体とポリスチレンスルホン酸（ＰＳＳ）等の混合物を、極性溶媒に溶解させた組成物を用いることができる。極性溶媒としては、例えば、イソプロピルアルコール（ＩＰＡ）、ノルマルブタノール、γ−ブチロラクトン、Ｎ−メチルピロリドン（ＮＭＰ）、１，３−ジメチル−２−イミダゾリジノン（ＤＭＩ）及びその誘導体、カルビト−ルアセテート、ブチルカルビト−ルアセテート等のグリコールエーテル類等を挙げることができる。
【００８０】
より具体的な第１組成物の組成としては、例えば、ＰＥＤＯＴ／ＰＳＳ混合物：７．２５重量％、水：５２．７５重量％、メタノール：５重量％、ＩＰＡ：５重量％、ＤＭＩ：５０重量％、γ−グリジルオキシプロピルトリメトキシシラン：０・０８重量％である。また、第１組成物の粘度は２〜２０Ｐｓ程度が好ましい。なお、本発明において、第１組成物の組成は上記例に限定されるものではない。また、正孔注入／輸送層の形成材料として、赤（Ｒ）、緑（Ｇ）、青（Ｂ）の各発光層に対して同じ材料を用いてもよく、各発光層ごとに変えてもよい。
【００８１】
第１組成物の吐出量は、バンクによる窪み（開口）の大きさ、形成しようとする正孔注入／輸送層の厚さ、第１組成物中の正孔注入／輸送層形成材料の濃度等により決定される。
また、第１組成物を一度にバンク間に配置してもよく、数回に分けて配置してもよい。この場合、各回における第１組成物の量は同一でもよく、各回ごとにその量を変えてもよい。さらに、ある画素電極に対して毎回同じ位置から第１組成物を吐出してもよく、各回ごとに位置をずらしながら吐出してもよい。
【００８２】
続いて、図１３に示すように、画素電極１４１上に配置された第１組成物を乾燥させる。すなわち、第１組成物に含まれる極性溶媒を蒸発させ、画素電極１４１上に正孔注入／輸送層２９０ａを形成する。本例では、バンク２８１表面（壁面及び上面）が撥液性に加工され、正孔注入／輸送層の平坦化に最適な動的接触角（後退接触角）になっているので、乾燥処理後において、バンク２８１の間に均一な厚さの正孔注入／輸送層２９０ａが形成される。
【００８３】
乾燥処理は、例えば窒素雰囲気中、室温で圧力を例えば１３３．３Ｐａ（１Ｔｏｒｒ）程度にして行う。圧力が低すぎると第１組成物の液滴が突沸するので好ましくない。また、温度を室温以上にすると、極性溶媒の蒸発速度が高まり、平坦な膜を形成する事が困難となりやすい。
また、乾燥処理後、窒素中、好ましくは真空中で２００℃で１０分程度加熱する熱処理を行うとよい。これにより、正孔注入／輸送層２９０ａ内に残存する極性溶媒や水を除去することができる。
【００８４】
（３）発光層形成工程
次に、発光層形成工程では、図１４に示すように、上記正孔注入／輸送層形成工程と同様に、液滴吐出法（インクジェット法）を用いることにより、各色（例えばここでは青色（Ｂ））の発光層の形成材料を含む第２組成物を正孔注入／輸送層２９０ａ上に吐出する。
【００８５】
すなわち、バンク２８１の開口位置にインクジェットヘッドＨ３の吐出ノズルＨ４を配置し、インクジェットヘッドＨ３と基板１２１とを相対的に移動させながら、吐出ノズルＨ４から１滴当たりの液量が制御された第２組成物の液滴を正孔注入／輸送層２９０ａ上に吐出する。
【００８６】
発光層形成材料としては、［化１］〜［化５］に示すポリフルオレン系高分子誘導体や、（ポリ）パラフェニレンビニレン誘導体、ポリフェニレン誘導体、ポリビニルカルバゾール、ポリチオフェン誘導体、ペリレン系色素、クマリン系色素、ローダミン系色素、あるいは上記高分子に有機ＥＬ材料をドープして用いる事ができる。例えば、ルブレン、ペリレン、９，１０-ジフェニルアントラセン、テトラフェニルブタジエン、ナイルレッド、クマリン６、キナクリドン等をドープすることにより用いることができる。
【００８７】
第２組成物の吐出量は、バンクによる窪み（開口）の大きさ、形成しようとする発光層の厚さ、第２組成物中の発光層形成材料の濃度等により決定される。
また、第２組成物を一度にバンク間に配置してもよく、数回に分けて配置してもよい。この場合、各回における第１組成物の量は同一でもよく、各回ごとにその量を変えてもよい。さらに、ある画素電極に対して毎回同じ位置から第１組成物を吐出してもよく、各回ごとに位置をずらしながら吐出してもよい。
【００８８】
続いて、図１５に示すように、画素電極１４１上に配置された第２組成物を乾燥させる。すなわち、第２組成物に含まれる溶媒（非極性溶媒）を蒸発させ、正孔注入／輸送層２９０ａ上に発光層２９０ｂ（青色（Ｂ）の発光層２９０ｂ3）を形成する。
また、図１６に示すように、青色の発光層２９０ｂ3と同様に、正孔注入／輸送層２９０ａ上に、赤色（Ｒ）、緑色（Ｇ）の発光層２９０ｂ1、２９０ｂ2を形成する。
なお、青色の発光層２９０ｂ3の場合、乾燥処理は、例えば、窒素雰囲気中、室温で圧力を１３３．３Ｐａ（１Ｔｏｒｒ）程度として５〜１０分行う条件とする。緑色の発光層２９０ｂ2、及び赤色の発光層２９０ｂ1の場合、発光層形成材料の成分数が多いために素早く乾燥させることが好ましく、例えば、４０℃で窒素の吹き付けを５〜１０分行う条件とするとよい。その他の乾燥の手段として、遠赤外線照射法、高温窒素ガス吹付法等を用いてもよい。
【００８９】
（４）対向電極（陰極）形成工程
次に対向電極（陰極）形成工程では、図１７に示すように、発光層２９０ｂ及びバンク２８１の全面に陰極１５４（対向電極）を形成する。
陰極１５４は複数の材料を積層して形成してもよい。例えば、発光層に近い側には仕事関数が小さい材料を形成することが好ましく、例えばＣａ、Ｂａ等を用いることが可能であり、また材料によっては下層にＬｉＦ等を薄く形成した方がよい場合もある。また、上部側（封止側）には下部側よりも仕事関数が高い材料、例えばＡｌを用いる事もできる。
フッ化リチウムは、発光層２９０ｂ上のみに形成してもよく、さらに所定の色に対応して形成する事ができる。例えば、青色（Ｂ）発光層２９０ｂ3上のみに形成してもよい。この場合、他の赤色（Ｒ）発光層及び緑色（Ｇ）発光層２９０ｂ1、２９０ｂ2には、カルシウムからなる上部陰極層が接することとなる。
これらの陰極１５４は、例えば蒸着法、スパッタ法、ＣＶＤ法等を用いて形成することが可能であるが、熱による発光層２９０ｂの損傷を防止する上で、本例では蒸着法を用いる。
また、陰極１５４の上部には、Ａｌ膜、Ａｇ膜等を用いることが好ましい。また、その厚さは、例えば１００〜１０００ｎｍの範囲が好ましく、特に２００〜５００ｎｍ程度がよい。
また陰極１５４上に、酸化防止のためにＳｉＯ2、ＳｉＮ等の保護層を設けてもよい。
【００９０】
以上の工程により、基板１２１上に発光部１４０が形成され、有機ＥＬ素子が形成される。この後、有機ＥＬ素子が形成された基板１２１を封止し、基板１２１の配線に陰極１５４を接続するとともに、基板１２１上あるいは外部に設けられる駆動ＩＣ（駆動回路）に回路素子部１４６の配線を接続することにより、有機ＥＬ表示装置が完成する。
【００９１】
図１８（ａ）〜（ｃ）は、本発明の電子機器の実施の形態例を示している。
本例の電子機器は、上述した有機ＥＬ表示装置等の本発明の電気光学装置を表示手段として備えている。
図１８（ａ）は、携帯電話の一例を示した斜視図である。図１８（ａ）において、符号６００は携帯電話本体を示し、符号６０１は前記の表示装置を用いた表示部を示している。
図１８（ｂ）は、ワープロ、パソコンなどの携帯型情報処理装置の一例を示した斜視図である。図１８（ｂ）において、符号７００は情報処理装置、符号７０１はキーボードなどの入力部、符号７０３は情報処理装置本体、符号７０２は前記の表示装置を用いた表示部を示している。
図１８（ｃ）は、腕時計型電子機器の一例を示した斜視図である。図１８（ｃ）において、符号８００は時計本体を示し、符号８０１は前記の表示装置を用いた表示部を示している。
図１８（ａ）〜（ｃ）に示すそれぞれの電子機器は、本発明の電気光学装置を表示手段として備えているので、品質の優れた表示を実現することができる。
【００９２】
以上、添付図面を参照しながら本発明に係る好適な実施例について説明したが、本発明は係る例に限定されないことは言うまでもない。上述した例において示した各構成部材の諸形状や組み合わせ等は一例であって、本発明の主旨から逸脱しない範囲において設計要求等に基づき種々変更可能である。
【００９３】
【実施例】
アクリル樹脂からなるバンクが形成された基板と、バンクと同じアクリル樹脂からなる平基板とを用意し、各基板に対して、上述したＣＦ4プラズマ処理を行った。処理時間は、１．０〜６．６ｓｅｃの間で変化させた。
また、上記ＣＦ4プラズマ処理の後、上記バンクが形成された基板に対して、上述した正孔注入／輸送層用の液滴材料を吐出し、バンクによって区画された領域に正孔注入／輸送層を形成し、その膜厚のプロファイルを測定した。液体材料の組成は、ＰＥＤＯＴ／ＰＳＳ混合物：７．２５重量％、水：５２．７５重量％、メタノール：５重量％、ＩＰＡ：５重量％、ＤＭＩ：５０重量％、γ−グリジルオキシプロピルトリメトキシシラン：０・０８重量％である。なお、液滴材料の乾燥は、減圧乾燥の後、２００℃で１０分間のベーキングを行った。
【００９４】
その結果、処理時間が１．１７〜１．４ｓｅｃのとき、最も理想的な膜厚のプロファイルが得られた。処理時間が１．１７ｓｅｃ未満だと、撥液性が不十分となり、バンクの壁面近くの膜厚が厚くなるので好ましくなく、１．４ｓｅｃを超えると、撥液性が高くなりすぎて、バンクの壁面近くの膜厚が薄くなるので好ましくない。
【００９５】
一方、上記平基板に対して、上記ＣＦ4プラズマ処理の後、協和界面科学社製ＣＡ−Ｗ接触角測定装置を用いて、先の図２を用いて説明した測定方法に従って、上記液体材料に対する動的接触角（後退接触角）と、静的接触角とを測定した。静的接触角の測定にはθ／２法を用いた。その結果を以下に示す。

【００９６】
上記結果から、動的接触角（後退接触角）を指標として用いることにより、撥液化の処理条件を管理できることが確認された。すなわち、動的接触角（後退接触角）が２９°程度〜４５°程度の範囲内になるように、プラズマ処理の処理条件を管理することにより、理想的で平坦な膜厚のプロファイルが得られることが確認された。これに対し、静的接触角では上記管理は難しいことがわかった。
【００９７】
【発明の効果】
本発明の電気光学装置の製造方法及びその装置によれば、バンクの表面を撥液性に加工する際に、動的接触角を指標として用いることにより、膜の平坦化に対する撥液化の処理条件の最適化が確実に行われる。したがって、バンクによって区画された領域内に平坦な膜を容易かつ安定的に形成することができる。
【００９８】
また、本発明の電気光学装置によれば、有機ＥＬ素子の構造を最適化し、その性能の向上を図ることができる。
【００９９】
また、本発明の電子機器によれば、上記電気光学装置を表示手段として備えることから、表示手段の性能を向上させることができる。
【図面の簡単な説明】
【図１】 本発明の電気光学装置としての有機ＥＬ装置の製造方法の概念的に示す図である。
【図２】 動的接触角（後退接触角）の測定例を示す図である。
【図３】 本発明の電気光学装置としての有機ＥＬ装置の製造装置の実施の形態例を模式的に示す図である。
【図４】 本発明の電気光学装置の実施の形態例である有機ＥＬ表示装置の構成を模式的に示す図である。
【図５】 有機ＥＬ表示装置における画素領域近傍の断面構造を拡大した図である。
【図６】 バンクの平面構造の形態例を模式的に示す図である。
【図７】 プラズマ処理装置の構成例を模式的に示す図である。
【図８】 プラズマ処理室の構成例を模式的に示す図である。
【図９】 有機ＥＬ装置の製造方法を説明する工程図である。
【図１０】 有機ＥＬ装置の製造方法を説明する工程図である。
【図１１】 ピエゾ方式による液滴吐出の原理を説明するための図である。
【図１２】 有機ＥＬ装置の製造方法を説明する工程図である。
【図１３】 有機ＥＬ装置の製造方法を説明する工程図である。
【図１４】 有機ＥＬ装置の製造方法を説明する工程図である。
【図１５】 有機ＥＬ装置の製造方法を説明する工程図である。
【図１６】 有機ＥＬ装置の製造方法を説明する工程図である。
【図１７】 有機ＥＬ装置の製造方法を説明する工程図である。
【図１８】 本発明の電子機器の実施の形態例を示す図である。
【図１９】 有機ＥＬ表示装置の要部の代表的な構成を示す断面模式図である。
【符号の説明】
１０，２８１…バンク、１２…膜、２０…有機ＥＬ装置の製造装置（電気光学装置の製造装置）、２１…撥液化装置、２２…測定装置、２３…膜形成装置、２４…制御装置、１００…有機ＥＬ表示装置、１０２…画素領域、１２１…基板、θ…動的接触角（後退接触角）。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electro-optical device manufacturing method, an electro-optical device manufacturing apparatus, an electro-optical device, and an electronic apparatus.
[0002]
[Prior art]
An electro-optical device (organic EL display device) including an organic electroluminescence (hereinafter referred to as EL) element as a light-emitting element is high-intensity and self-luminous, can be driven by a DC low voltage, and has a high response speed. As a next-generation display device, it has excellent display performance due to the fact that it emits light from a solid organic film, and the display device can be made thinner, lighter, lower in power consumption, and larger in size. Expected.
[0003]
FIG. 19 is a schematic cross-sectional view showing a typical configuration of a main part of an organic EL display device. In the organic EL display device, a circuit element portion 901, a pixel electrode (anode) 902, an organic functional layer 903 including a light emitting layer, a counter electrode (cathode) 904, a sealing portion 905, and the like are sequentially stacked on a substrate 900. Consists of structure. Among these, the pixel electrode 902, the functional layer 903, the counter electrode 904, and the like constitute a light emitting element (organic EL element).
[0004]
In this display device, the functional layer 903 sandwiched between the pixel electrode 902 and the counter electrode 904 emits light by driving control of the circuit element portion 901, and the light is emitted through the circuit element portion 901 and the substrate 900. At the same time, light emitted from the functional layer 903 to the opposite side of the substrate 900 is reflected by the counter electrode 904 and emitted through the circuit element portion 901 and the substrate 900.
[0005]
As a technique for arranging a material for forming an organic EL element on a substrate, a method of forming a film by vapor deposition, a method of applying by various coating methods, and the like are known. Further, when a liquid material having a low viscosity is disposed on the substrate, a bank (reference numeral 910 shown in FIG. 19) is used as a partition member for partitioning the regions so that the materials of the plurality of adjacent regions are not mixed with each other. Often provided.
[0006]
[Problems to be solved by the invention]
However, when a liquid material is disposed in a region partitioned by the bank, the liquid material is affected by the surface (wall surface) of the bank, and the flatness of the formed layer (or film) is likely to be impaired. When the flatness of the layers constituting the organic EL element is lowered, unevenness of light emission occurs and the performance of the organic EL display device is likely to be lowered.
[0007]
The present invention has been made in view of the above-described circumstances, and an electro-optical device manufacturing method and an electro-optical device manufacturing method that can easily and stably form a flat film in a region partitioned by a bank. An object is to provide an apparatus.
Another object of the present invention is to provide an electro-optical device with improved performance. Another object of the present invention is to provide an electronic apparatus with improved display means performance.
[0008]
[Means for Solving the Problems]
The method of manufacturing an electro-optical device according to the present invention includes a step of forming a film by disposing a liquid material in a region partitioned by a bank. In the method of manufacturing an electro-optical device, plasma processing is performed before disposing the liquid material. From the liquid repellent step of processing the surface of the bank to make it liquid repellent, the measurement step of measuring the dynamic contact angle of the object made of the same material as the bank with respect to the liquid material, and the measurement result of the measurement step And determining the processing conditions of the lyophobic process. In the lyophobic process, the dynamic contact angle is measured as needed, and the processing conditions are managed so as not to deviate from the target value.
According to the above electro-optical device manufacturing method, when the surface of the bank is processed to be liquid repellent, the use of the dynamic contact angle as an index facilitates management of the liquid repellent processing conditions. For this reason, the processing conditions for the liquid repellency for the flattening of the film are surely optimized. The liquid repellency referred to here is a characteristic that shows non-affinity with respect to a liquid material arranged in a region partitioned by banks.
[0009]
Specifically, in the liquid repellent step, for example, the surface of the bank is processed to be liquid repellent by plasma processing, and the processing time of the plasma processing may be managed using the dynamic contact angle as an index. The liquid repellency of the bank surface can be controlled by changing the processing time of the plasma processing. In addition, the plasma treatment can give various characteristics to the surface to be treated by the selection of raw materials and the like, and is easy to control.
[0010]
In the method for manufacturing the electro-optical device, it is preferable that in the liquid repellency process, the processing conditions are controlled so that the dynamic contact angle is within a range of 29 ° to 45 °. If the dynamic contact angle is less than 29 °, the liquid repellency becomes insufficient and the film thickness in the vicinity of the bank becomes thick, which is not preferable. If the dynamic contact angle exceeds 45 °, the liquid repellency becomes too high. This is not preferable because the film thickness in the vicinity of the bank becomes thin.
[0011]
The electro-optical device manufacturing method may further include a lyophilic step of processing the surface of the bank to be lyophilic before the lyophobic step. By processing the surface of the bank to be lyophilic before the liquid repellency, the liquid repellency can be promoted. The liquid repellency referred to here is a characteristic that shows non-affinity with respect to a liquid material arranged in a region partitioned by banks.
[0012]
The electro-optical device manufacturing apparatus according to the present invention is an electro-optical device manufacturing apparatus including a film forming apparatus that forms a film by disposing a liquid material in a region partitioned by a bank, and repels the surface of the bank by plasma treatment. A liquid repellent device that processes liquid, a measuring device that measures a dynamic contact angle of an object made of the same material as the bank with respect to the liquid material, and processing conditions of the liquid repellent device are determined from the measurement results of the measuring device. And the lyophobic device performs processing based on the processing conditions.
According to the electro-optical device manufacturing apparatus, the surface of the bank can be processed to be liquid repellent with the dynamic contact angle with respect to the liquid material as an index.
In this case, the processing conditions of the lyophobic device are managed based on the measurement results of the measuring device, so that the lyophobic processing conditions are reliably optimized, and the film formed between the banks Flattened stably.
[0013]
The electro-optical device manufacturing apparatus may further include a lyophilic device that processes the bank surface to be lyophilic before processing the bank surface to be lyophobic. By processing the surface of the bank to be lyophilic before the lyophobic step, it becomes possible to promote the lyophobic property.
[0014]
The electro-optical device of the present invention is manufactured using the electro-optical device manufacturing apparatus.
According to the electro-optical device, since the electro-optical device is manufactured using the manufacturing apparatus described above, the film formed between the banks is stably flattened, so that the performance can be improved. .
[0015]
An electronic apparatus according to an aspect of the invention includes the above-described electro-optical device as a display unit.
According to the electronic device, the performance of the display means can be improved.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described in detail below.
FIG. 1 is a diagram conceptually illustrating a method for manufacturing an organic EL device as an electro-optical device of the present invention. The method for manufacturing an organic EL device according to the present invention includes a step (FIG. 1B) of forming a film 12 by disposing a liquid material in a region partitioned by a bank 10 and drying the liquid material, and the liquid material. Before the arrangement of the step, there is a step of processing the surface of the bank 10 to be liquid repellent (FIG. 1A).
[0017]
The bank 10 is provided on a base and is made of, for example, an organic material such as a resin or an inorganic material. Further, as the liquid material, both aqueous and organic materials such as a material for forming a functional layer (including a light emitting layer and a hole transport layer) used in the organic EL device are applied.
[0018]
When a film (or a layer) is formed with a liquid material inside the depression by the bank 10, the liquid material is affected by the surface (wall surface) of the bank 10 and the flatness of the film is easily impaired. The present inventors have paid attention to this general fact and the fact that when a film is formed between the banks 10, the flatness of the film varies greatly according to the characteristics of the wall surface of the bank 10, and has earnestly paid attention. As a result of investigation, it is clarified that the flatness of the film formed between the banks 10 is related to the dynamic contact angle θ of the wall surface of the bank 10 with respect to the liquid material, and by using this dynamic contact angle θ as an index, The present invention has been completed.
[0019]
In other words, in the present invention, by using the dynamic contact angle as an index, the management of the liquid repellency treatment conditions is facilitated. For example, for a liquid material to be used, a target value of a dynamic contact angle that is optimal for flattening the film is obtained in advance, and thereafter the liquid repellent process is performed so that the wall surface of the bank becomes the dynamic contact angle. By managing the conditions, a flat film can be obtained easily and reliably. In other words, by measuring the dynamic contact angle of the bank without actually forming a film, it is possible to determine whether the characteristics of the bank wall surface after the liquid repellent treatment are suitable for film planarization. Management of liquefaction process conditions becomes easy. Therefore, in the manufacturing method of the present invention, the treatment condition for liquid repellency is reliably optimized, and a flat film can be stably obtained.
[0020]
Examples of the liquid repellency method include a plasma treatment method (plasma polymerization method), a eutectoid plating method, a liquid repellency method using gold thiol, or a FAS (fluoroalkylsilane) method. Various known methods can be employed. Among these, the plasma processing method has an advantage that various characteristics can be given to the surface to be processed by the selection of raw materials and the like, and the control is easy.
[0021]
In the plasma processing method, for example, a fluorine-based processing gas such as tetrafluoromethane (carbon tetrafluoride) is turned into plasma and irradiated onto the surface of the target object (CF4 plasma processing). As a result, fluorine groups are introduced to the surface of the target object and liquid repellency is imparted. The processing gas is not limited to tetrafluoromethane (carbon tetrafluoride), and other fluorocarbon gases may be used. Furthermore, a treatment gas other than fluorine-based gas may be used as long as it can impart liquid repellency to the liquid material.
[0022]
When the surface of the target object is fluorinated by the plasma polymerization method, depending on the type of the target object, the surface can be lyophilic or activated in advance to promote the fluorination. Such pretreatment can be carried out, for example, by using oxygen as a treatment gas in the plasma polymerization method described above (O2 plasma treatment). In this case, by irradiating the surface of the target object with oxygen in a plasma state, the surface becomes lyophilic or activated.
[0023]
Further, when liquid repellency is imparted to the bank by the plasma treatment method, the dynamic contact angle of the bank surface with respect to the liquid material can be controlled by changing the treatment time of the plasma treatment. For example, if the time for irradiating the bank surface with the processing gas in the plasma state is increased, the liquid repellency of the bank surface is improved and the dynamic contact angle is increased. Therefore, by managing the plasma processing time based on the measurement result of the dynamic contact angle of the bank surface, the dynamic contact angle of the bank surface is brought close to the optimal dynamic contact angle for film planarization. be able to.
[0024]
Several methods are known for measuring the dynamic contact angle, but droplets are formed on the surface of the object to be measured, the droplets are deformed, and the contact angle around the droplets when deformed In general, it is necessary to obtain (advance contact angle, receding contact angle). In this case, the contact angle can be obtained by observing with an observation means such as a CCD camera and analyzing the observation result.
[0025]
FIG. 2 shows an example of measurement of the dynamic contact angle. In this example, an object 15 to be measured is placed on a stage 16, a droplet is created on the object 15, and a needle 17 is placed on the droplet. Contact. Thereafter, the stage 16 is moved while the needle 17 is fixed in place. At this time, the contact angle of the end of the object 15 in the moving direction of the stage 16 becomes the dynamic contact angle θ (in this example, the receding contact angle).
[0026]
In the measurement of the dynamic contact angle, the bank may not be directly measured, but may be indirectly measured using an object having at least a surface portion having the same material and characteristics as the bank as a measurement target. For example, the surface of an object made of the same material as the bank is processed to be liquid repellent under the same processing conditions as the bank, and the dynamic contact angle is measured for the object surface after the processing. Thereby, the dynamic contact angle on the bank surface after the liquid repellent treatment can be indirectly measured. When using indirect measurement, it is possible to check the liquid repellency of the bank and manage the processing conditions without interrupting the manufacturing process in the manufacturing process of the organic EL device. Therefore, a flat film can be obtained more stably.
[0027]
FIG. 3 is a diagram conceptually showing an apparatus for manufacturing an organic EL device as an electro-optical device of the present invention. The organic EL device manufacturing apparatus 20 of the present invention includes a liquid repellent device 21 that processes the surface (wall surface) of the bank 10 to make it liquid repellent, a measuring device 22 that measures a dynamic contact angle with respect to a liquid material, and the bank 10. A film forming apparatus 23 that forms a film by disposing a liquid material in the partitioned area, and a control apparatus 24 that comprehensively controls them, and based on the manufacturing method of the present invention described above, an organic EL device is provided. To manufacture. That is, before the liquid material is arranged by the film forming device 23, the surface of the bank 10 is processed to be liquid repellent by the liquid repellent device 21 using the dynamic contact angle with respect to the liquid material as an index.
[0028]
In the manufacturing apparatus 20, for example, a target value of a dynamic contact angle that is optimal for film planarization is stored in the control device 24. The measuring device 22 measures the dynamic contact angle on the bank surface and sends the measurement result to the control device 24. The control device 24 determines processing conditions of the liquid repellent device 21 such as processing time so that the dynamic contact angle of the bank surface after the liquid repellent treatment approaches the target value. In measuring the dynamic contact angle, the bank may not be directly measured, but the dynamic contact angle may be measured using an object made of the same material as the bank instead. When the liquid repellency treatment conditions are determined, the bank surface is processed into liquid repellency by the liquid repellency apparatus 21 based on the treatment conditions.
[0029]
After the bank surface is processed to be liquid repellent, a liquid material is placed inside the bank after the liquid repellent treatment by the film forming device 23. At this time, since the liquid repellency of the bank surface is processed to a desired dynamic contact angle, the film 12 (or layer) formed between the banks is satisfactorily flattened. For the purpose of stably obtaining a flat film, the dynamic contact angle of the bank surface after the liquid repellent treatment (or the object surface that replaces it) is measured as needed, and the liquid repellent device 21 does not deviate from the target value. It is preferable to manage the processing conditions.
[0030]
Thus, in the organic EL device manufacturing apparatus 20 of the present invention, the film forming apparatus is managed by managing the processing conditions of the lyophobic apparatus 21 based on the measurement result of the dynamic contact angle of the bank surface by the measuring apparatus 22. The film obtained by 23 is stably flattened. In addition, by providing a lyophilic device that processes the bank surface to be lyophilic before the lyophobic device 21, it is possible to promote lyophobicity.
[0031]
Here, as a liquid material arrangement technique in the film forming apparatus, that is, a technique of arranging the liquid material inside the depression by the bank, a droplet discharge method (so-called inkjet method), a dispense coating method, a spin coating method, or the like Various coating methods can be applied. Among the coating methods, the droplet discharge method has the advantage that the use of the material is less wasteful and a desired amount of material can be accurately disposed at a desired position.
[0032]
Examples of the droplet discharge technique (inkjet method) include a charge control method, a pressure vibration method, an electromechanical conversion method, an electrothermal conversion method, and an electrostatic suction method. In the charge control method, a charge is applied to a material by a charging electrode, and the flight direction of the material is controlled by a deflection electrode and discharged from a nozzle. In addition, the pressure vibration method applies an ultra-high pressure to the material and discharges the material to the tip of the nozzle. When the control voltage is not applied, the material moves straight and is discharged from the nozzle, and the control voltage is applied. Electrostatic repulsion occurs between the materials and the materials are scattered and not discharged from the nozzle. In addition, the electromechanical conversion method (piezo method) utilizes the property that a piezo element (piezoelectric element) deforms in response to a pulsed electric signal, and can be used in a space where material is stored by deformation of the piezo element. Pressure is applied through a flexible substance, and the material is pushed out from this space and discharged from the nozzle. In the electrothermal conversion method, a material is rapidly vaporized by a heater provided in a space in which the material is stored to generate bubbles, and the material in the space is discharged by the pressure of the bubbles. In the electrostatic attraction method, a minute pressure is applied in a space in which the material is stored, a meniscus of the material is formed on the nozzle, and an electrostatic attractive force is applied in this state before the material is drawn out. In addition to this, techniques such as a system that uses a change in the viscosity of a fluid due to an electric field and a system that uses a discharge spark are also applicable.
[0033]
FIG. 4 shows an embodiment in which the electro-optical device of the present invention is applied to an active matrix display device (organic EL display device), and an organic EL element manufactured using the manufacturing device of the present invention emits light. Provide as an element. In addition, this display device employs an active driving method using thin film transistors.
[0034]
The display device 100 has a structure in which a circuit element portion 146 including a thin film transistor as a circuit element, a light emitting portion 140 including a light emitting layer, a cathode 154, a sealing portion 147, and the like are sequentially stacked on a substrate 121.
[0035]
As the substrate 121, a glass substrate is used in this example. As a substrate in the present invention, in addition to a glass substrate, various known substrates used for electro-optical devices and circuit substrates such as a silicon substrate, a quartz substrate, a ceramic substrate, a metal substrate, a plastic substrate, and a plastic film substrate are applied. The
[0036]
A plurality of pixel regions 102 as light emitting regions are arranged in a matrix on the substrate 121. When color display is performed, for example, each of red (Red), green (Green), and blue (Blue) colors is supported. Pixel regions 102 to be arranged are arranged in a predetermined arrangement.
In each pixel region 102, a pixel electrode 141 is disposed, and in the vicinity thereof, a signal line 132, a common power supply line 133, a scanning line 131, scanning lines for other pixel electrodes (not shown), and the like are disposed. As the planar shape of the pixel region 102, an arbitrary shape such as a circle or an oval can be applied in addition to the rectangle shown in the figure.
[0037]
The sealing portion 147 prevents intrusion of water or oxygen to prevent oxidation of the cathode 154 or the light emitting portion 140, and includes a sealing resin applied to the substrate 121, and a sealing substrate bonded to the substrate 121 ( Sealing cans) 148 and the like. As the material of the sealing resin, for example, a thermosetting resin or an ultraviolet curable resin is used, and in particular, an epoxy resin that is one kind of thermosetting resin is preferably used. The sealing substrate 148 is made of glass, metal, or the like, and the substrate 121 and the sealing substrate 148 are bonded to each other with a sealant. A desiccant is disposed inside the substrate 121, and an N2 gas filling layer 149 filled with N2 gas is formed in a space formed between the substrates.
[0038]
In the pixel region 102, a first thin film transistor 142 for switching in which a scanning signal is supplied to the gate electrode through the scanning line 131, and a holding for holding an image signal supplied from the signal line 132 through the thin film transistor 142. The capacitor 145, the second driving thin film transistor 143 to which the image signal held by the holding capacitor 145 is supplied to the gate electrode, and the common supply line when electrically connected to the common power supply line 133 through the thin film transistor 143 A pixel electrode 141 (anode) through which a drive current flows from the electric wire 133 and a light emitting unit 140 sandwiched between the pixel electrode 141 and the counter electrode 154 (cathode) are provided. The light emitting unit 140 includes a layer (functional layer) including an organic EL layer as a light emitting layer, and the organic EL element that is a light emitting element includes a pixel electrode 141, a cathode 154, a light emitting unit 140, and the like.
[0039]
In the pixel region 102, when the scanning line 131 is driven and the first thin film transistor 142 is turned on, the potential of the signal line 132 at that time is held in the holding capacitor 145, and the second potential is changed depending on the state of the holding capacitor 145. The conductive state of the thin film transistor 143 is determined. In addition, current flows from the common power supply line 133 to the pixel electrode 141 through the channel of the second thin film transistor 143, and further, current flows to the counter electrode 154 through the light emitting unit 140. And according to the electric current amount at this time, the light emission part 140 light-emits.
[0040]
In the display device 100 of the present example, light emitted from the light emitting unit 140 to the substrate 121 side is transmitted through the circuit element unit 146 and the substrate 121 and emitted to the lower side (observer side) of the substrate 121 and emitted light. Light emitted from the portion 140 to the opposite side of the substrate 121 is reflected by the cathode 154, and the light passes through the circuit element portion 146 and the substrate 121 and is emitted to the lower side (observer side) of the substrate 121 (back). Emission type). Note that light emitted from the cathode side can be emitted from the cathode side by using a transparent material as the cathode 154 (top emission type). In this case, ITO, Pt, Ir, Ni, or Pd can be used as the transparent material for the cathode. Further, the thickness of the cathode is preferably about 75 nm, and it is more preferable to make it thinner than this thickness.
[0041]
FIG. 5 is an enlarged view of a cross-sectional structure in the vicinity of the pixel region 102 in the display device 100. In FIG. 5, three pixel regions 102 are shown.
In the circuit element portion 146, a base protective film 201 made of a silicon oxide film is formed on the substrate 121, and an island-shaped semiconductor film 204 made of polycrystalline silicon is formed on the base protective film 201. Note that a source region 204a and a drain region 204b are formed in the semiconductor film 204 by high concentration P ion implantation. A portion where P is not introduced is a channel region 204c.
[0042]
Further, a transparent gate insulating film 220 covering the base protective film 201 and the semiconductor film 204 is formed in the circuit element portion 146, and a gate electrode made of Al, Mo, Ta, Ti, W, or the like is formed on the gate insulating film 220. 229 (scanning lines) are formed, and a transparent first interlayer insulating film 250 and a second interlayer insulating film 270 are formed on the gate electrode 229 and the gate insulating film 220. The gate electrode 229 is provided at a position corresponding to the channel region 204 c of the semiconductor film 204. In addition, contact holes 275 and 276 are formed through the first and second interlayer insulating films 250 and 270 and connected to the source and drain regions 204a and 204b of the semiconductor film 204, respectively.
[0043]
On the second interlayer insulating film 270, a transparent pixel electrode 141 made of ITO or the like is formed by patterning in a predetermined shape, and one contact hole 275 is connected to the pixel electrode 141. The other contact hole 276 is connected to the feeder line 133.
Thus, the driving thin film transistor 143 connected to each pixel electrode 141 is formed in the circuit element portion 146. In the circuit element portion 146, the storage capacitor 145 and the switching thin film transistor 142 described above are formed, but these are not shown in FIG.
[0044]
The light emitting unit 140 includes a functional layer 290 stacked on each of the plurality of pixel electrodes 141... And a bank 281 provided between each pixel electrode 141 and the functional layer 290 to partition each functional layer 290. Consists of the subject. A cathode 154 is disposed on the functional layer 290. An organic EL element that is a light emitting element includes a pixel electrode 141, a cathode 154, a functional layer 290, and the like.
Here, the pixel electrode 141 is made of, for example, ITO, and is formed by patterning in a substantially rectangular shape in plan view. The thickness of the pixel electrode 141 is preferably in the range of 50 to 200 nm, and preferably about 150 nm. Further, a bank 281 is provided between the pixel electrodes 141.
[0045]
FIG. 6 shows a form example of the planar structure of the bank 281.
The bank 281 is located at the boundary of the plurality of pixel regions 102 and has openings corresponding to the arrangement of the plurality of pixel regions 102.
In the example of FIG. 6A, the banks 281 are provided in a lattice shape corresponding to the plurality of pixel regions 102 arranged in a matrix. In the example of FIG. 6B, the banks 281 are provided in a stripe shape corresponding to the plurality of pixel regions 102 arranged in a stripe shape. Note that the arrangement of the pixel region 102 and the planar shape of the bank 281 are not limited to this, and for example, a so-called delta arrangement of pixel regions that are shifted for each column and a bank shape corresponding to the so-called delta arrangement. In this example, the bank 281 has a lattice-like planar structure shown in FIG.
[0046]
Returning to FIG. 5, the bank 281 is made of an organic material layer formed of a resist having heat resistance and solvent resistance such as acrylic resin and polyimide resin. The thickness (height) of the bank 281 is set to about 0.1 to 3.5 μm, for example. If the thickness is less than 0.1 μm, the bank 281 tends to be thinner than the total thickness of the hole injection / transport layer and the light emitting layer, which will be described later, and the light emitting layer may overflow from the upper part of the bank 281, which is not preferable. On the other hand, if the thickness exceeds 3.5 μm, the step formed by the bank 281 increases, and step coverage of the cathode 154 formed on the bank 281 cannot be ensured. Further, if the thickness of the bank 281 is 2 μm or more, it is more preferable in that the insulation with the driving thin film transistor 143 can be increased. The bank thickness is an example, and the present invention is not limited to this.
[0047]
Further, the bank 281 is not limited to an organic material, and other materials may be used. For example, an organic bank layer may be stacked on an inorganic bank layer. In this case, for example, silicon nitride, silicon oxynitride, titanium nitride, tantalum nitride or the like is used as the inorganic bank layer. By providing the inorganic bank layer under the organic bank layer, it is possible to prevent the metal (for example, alkali metal (movable ions)) that has passed through the organic bank layer from entering the thin film transistor. Note that in the case where the banks 281 are stacked in multiple layers, each of the stacked layers does not need to have the above-described characteristics (liquid repellency), and at least one of the layers (for example, only the uppermost bank layer) is repellent. What is necessary is just to have liquidity.
[0048]
Further, the surface of the bank 281 is processed to be liquid repellent using the dynamic contact angle with respect to the liquid material as an index. In the region showing liquid repellency, the surface is subjected to fluorination treatment (liquid repellency treatment) by plasma treatment using tetrafluoromethane, tetrafluoromethane, or carbon tetrafluoride as a treatment gas. In this example, the dynamic contact angle (recessed contact angle) on the surface of the bank 281 is in the range of 29 ° to 45 °.
[0049]
The functional layer 290 includes a hole injection / transport layer 290a stacked on the pixel electrode 141 and a light emitting layer 290b formed adjacent to the hole injection / transport layer 290a. Note that another functional layer having other functions may be further formed adjacent to the light-emitting layer 290b. For example, an electron transport layer may be formed.
[0050]
The hole injection / transport layer 290a has a function of injecting holes into the light emitting layer 290b and a function of transporting holes inside the hole injection / transport layer 290a. By providing such a hole injecting / transporting layer 290a between the pixel electrode 141 and the light emitting layer 290b, device characteristics such as light emitting efficiency and lifetime of the light emitting layer 290b are improved. In the light emitting layer 290b, the holes injected from the hole injection / transport layer 290a and the electrons injected from the cathode 154 are recombined to obtain light emission.
[0051]
The light emitting layer 290b has three types, a red light emitting layer 290b1 that emits red (R), a green light emitting layer 290b2 that emits green (G), and a blue light emitting layer 290b3 that emits blue (B). The light emitting layers 290b1 to 290b3 are arranged in stripes.
[0052]
As a material for forming the hole injection / transport layer 290a, for example, a mixture of a polythiophene derivative such as polyethylenedioxythiophene and polystyrenesulfonic acid can be used. In addition, various known materials can be used without any particular limitation, and examples thereof include pyrazoline derivatives, arylamine derivatives, stilbene derivatives, and triphenyldiamine derivatives. Specific contents thereof include, for example, JP-A-63-70257, JP-A-63-175860, JP-A-2-135359, JP-A-2-135361, JP-A-2-20988, JP-A-3-37992, It is described in JP-A-3-152184. Furthermore, as a material for forming the hole injection / transport layer, copper phthalocyanine (CuPc), polyphenylene vinylene which is polytetrahydrothiophenylphenylene, 1,1-bis- (4-N, N-ditolylaminophenyl) cyclohexane, Tris (8-hydroxyquinolinol) aluminum or the like is also applied.
[0053]
Examples of the material of the light-emitting layer 290b include (poly) paraphenylene vinylene derivatives, polyphenylene derivatives, polyfluorene derivatives, polyvinyl carbazole, polythiophene derivatives, perylene dyes, and coumarins shown in [Chemical Formula 1] to [Chemical Formula 5]. A dye, a rhodamine dye, or a polymer material thereof can be doped with rubrene, perylene, 9,10-diphenylanthracene, tetraphenylbutadiene, Nile red, coumarin 6, quinacridone, or the like.
[0054]
[Chemical 1]

[0055]
[Chemical 2]

[0056]
[Chemical 3]

[0057]
[Formula 4]

[0058]
[Chemical formula 5]

[0059]
The cathode 154 is formed on the entire surface of the light emitting unit 140 and plays a role of flowing a current through the functional layer 290 in a pair with the pixel electrode 141. The cathode 154 is configured by, for example, laminating a calcium layer and an aluminum layer. At this time, it is preferable to provide a cathode having a low work function for the cathode close to the light emitting layer, and in this embodiment, in particular, it plays a role of injecting electrons into the light emitting layer 290b in direct contact with the light emitting layer 290b. Further, depending on the material of the light emitting layer, lithium fluoride may form LiF between the light emitting layer 290b and the cathode 154 in order to emit light efficiently.
The red and green light emitting layers 290b1 and 290b2 are not limited to lithium fluoride, and other materials may be used. Therefore, in this case, a layer made of lithium fluoride may be formed only on the blue (B) light emitting layer 290b3, and other red and green light emitting layers 290b1 and 290b2 may be laminated other than lithium fluoride. Further, only calcium may be formed on the red and green light emitting layers 290b1 and 290b2 without forming lithium fluoride. In this case, the thickness of the lithium fluoride is preferably, for example, in the range of 2 to 5 nm, particularly about 2 nm. The thickness of calcium is preferably in the range of 2 to 50 nm, for example.
The aluminum forming the cathode 154 reflects light emitted from the light emitting layer 290b to the substrate 121 side, and is preferably made of an Ag film, a laminated film of Al and Ag, or the like in addition to the Al film. Further, the thickness is preferably in the range of, for example, 100 to 1000 nm, particularly about 200 nm. Further, an antioxidant protective layer made of SiO, SiO2, SiN or the like may be provided on aluminum.
[0060]
Next, regarding an example of a method for manufacturing the organic EL element (and organic EL display device), in particular, (1) a plasma processing step, (2) a hole injection / transport layer forming step, (3) a light emitting layer forming step, (4) The counter electrode (cathode) forming step will be described in detail with reference to FIGS.
[0061]
(1) Plasma treatment process
In the plasma treatment step, a substrate 121 on which a thin film transistor 143 as a circuit element, a pixel electrode 141, and a bank 281 are formed is input. The plasma treatment process is aimed at activating the surface of the pixel electrode 141, surface-treating the surface of the bank 281 and the like, and performing lyophilic treatment on the surface of the pixel electrode 141 and lyophobic treatment on the surface of the bank 281. Do.
[0062]
The plasma treatment process is roughly divided into (a) a preheating process, (b) an activation process (lyophilic process), (c) a lyophobic process, and (d) a cooling process. However, the present invention is not limited to this, and a process may be added or deleted as necessary.
[0063]
FIG. 7 schematically shows a configuration example of a plasma processing apparatus used in the plasma processing step. The plasma processing apparatus 50 includes a preheating processing chamber 51, a first plasma processing chamber 52, a second plasma processing chamber 53, a cooling processing chamber 54, and a transfer device 55 for transferring a substrate to each of the processing chambers 51 to 54. . In this example, the processing chambers 51 to 54 are arranged radially with the transfer device 55 as the center.
[0064]
In the plasma processing apparatus, first, the substrate is preheated in the preheating treatment chamber 51, and then the activation treatment and the liquid repellency treatment are performed in the first and second plasma treatment chambers 52,53. After the liquid repellent treatment, the substrate is transferred to the cooling treatment chamber 54, and the substrate is cooled to room temperature. Hereinafter, each process will be described in detail.
[0065]
(A) Preheating step
In the preheating step, the substrate including the bank is heated to a predetermined temperature in the preheating treatment chamber 51. The heating temperature is set to the same level as the processing temperature of the plasma processing that is the next step, and is, for example, 70 to 80 ° C. The main purpose of the preheating is to suppress the temperature fluctuation of the substrate in the next plasma processing and to improve the processing uniformity. As the heating means, for example, a structure in which a heater is built in a plate (stage) on which a substrate is mounted is used.
[0066]
(B) Activation process
In the activation step, plasma processing (O2 plasma processing) is performed on the substrate using oxygen as a processing gas in an air atmosphere. The purpose of the O2 plasma treatment is to adjust and control the work function of the pixel electrode, clean the surface of the pixel electrode, and make the surface of the pixel electrode lyophilic. Also, the O2 plasma treatment makes the bank surface lyophilic with the pixel electrodes, and promotes the lyophobicity of the bank in the next lyophobic process.
[0067]
FIG. 8 is a diagram schematically showing a main configuration of the first plasma processing apparatus 52. In FIG. 8, a substrate 121 including a bank is placed on a sample stage 56 with a built-in heater, and a plasma discharge electrode is disposed above the substrate 121 with a predetermined gap interval (for example, about 0.5 to 2 mm). 57 is arranged to face the substrate 121. The substrate 121 is heated by the sample stage 56 and is transported through the sample stage 56 in the direction of the arrow in the drawing at a predetermined transport speed. During the transfer, the substrate 121 is irradiated with oxygen in a plasma state.
[0068]
The processing conditions of the O2 plasma processing are, for example, a plasma power of 100 to 800 kW, an oxygen gas flow rate of 50 to 100 ml / min, a transport speed of 0.5 to 10 mm / sec, and a substrate temperature of 70 to 90 ° C. The sample stage 56 is heated mainly to keep the preheated substrate warm. The processing atmosphere is not limited to the air atmosphere, and may be, for example, a vacuum.
[0069]
By the O 2 plasma treatment, as shown in FIG. 9, the electrode surface of the pixel electrode 141 and the wall surface and upper surface of the bank 281 are subjected to lyophilic treatment. That is, a hydroxyl group is introduced into each of these surfaces to impart lyophilic properties. In FIG. 9, the lyophilic portion is indicated by a one-dot chain line. By the O2 plasma treatment, the above-described pixel electrode cleaning and work function adjustment are also performed.
[0070]
(C) Liquid repellent treatment process
In the lyophobic process, the substrate is subjected to plasma processing (CF4 plasma processing) using tetrafluoromethane as a processing gas in an air atmosphere. The main configuration of the second plasma processing chamber 53 (see FIG. 7) is substantially the same as that of the first plasma processing chamber 52 shown in FIG. That is, the substrate is heated and transported by the sample stage, and the substrate is irradiated with plasma tetrafluoromethane (carbon tetrafluoride).
[0071]
The processing conditions of the CF4 plasma processing are, for example, plasma power of 100 to 800 kW, tetrafluoromethane gas flow rate of 50 to 100 ml / min, substrate transfer speed of 0.5 to 10 mm / sec, and substrate temperature of 70 to 90 ° C. When other processing conditions are constant, the processing time of the plasma processing can be changed by changing the transport speed of the substrate. In this example, the processing time of the plasma treatment is managed using the dynamic contact angle of the bank surface with respect to the liquid material (first composition described later) for forming the hole injection / transport layer as an index.
[0072]
Specifically, the processing time is managed so that the receding contact angle as the dynamic contact angle of the bank surface with respect to the liquid material falls within a range of 29 ° to 45 °. The target value of the receding contact angle is obtained in advance so as to be optimal for the flattening of the hole injection / transport layer. When the receding contact angle on the bank surface is less than 29 °, the liquid repellency becomes insufficient, and the film thickness in the vicinity of the bank of the hole injection / transport layer is undesirably increased. On the other hand, if the receding contact angle exceeds 45 °, the liquid repellency becomes too high and the film thickness in the vicinity of the bank of the hole injection / transport layer becomes thin, which is not preferable. Note that the sample stage is heated mainly for heat retention of the preheated substrate, as in the first plasma processing chamber. Further, the processing gas is not limited to tetrafluoromethane (carbon tetrafluoride), and other fluorocarbon gases may be used. The processing atmosphere is not limited to the air atmosphere, and may be, for example, a vacuum.
[0073]
As shown in FIG. 10, the wall surface and the upper surface of the bank 281 are subjected to the liquid repellent treatment by the CF 4 plasma treatment. That is, a fluorine group is introduced into each of these surfaces to impart liquid repellency. In FIG. 10, the region showing liquid repellency is indicated by a two-dot chain line. Organic substances such as an acrylic resin and a polyimide resin constituting the bank 281 are easily lyophobic when irradiated with plasma fluorocarbon. Further, before the lyophobic property, it has a feature that it is easy to be fluorinated by lyophilic treatment of O2 plasma.
Note that the electrode surface of the pixel electrode 141 is also somewhat affected by this CF4 plasma treatment, but it hardly affects wettability. In FIG. 10, a region showing lyophilicity is indicated by a one-dot chain line.
[0074]
(D) Cooling process
In the cooling step, the substrate after the plasma processing is cooled to a predetermined temperature in the cooling processing chamber 54 (see FIG. 7). The main purpose of cooling the substrate is to suppress the temperature fluctuation of the substrate in the next hole injection / transport layer forming step and to improve the uniformity of processing, and at room temperature or in the hole injection / transport layer forming step. The substrate is cooled to a predetermined management temperature. As the cooling means, for example, a structure in which a cooling device is built in a plate (stage) on which a substrate is mounted is used.
[0075]
(2) Hole injection / transport layer formation process
Next, in the hole injection / transport layer forming step, the first composition containing the hole injection / transport layer forming material is discharged onto the pixel electrode 141 by using a droplet discharge method (inkjet method). Thereafter, drying treatment and heat treatment are performed to form a hole injection / transport layer on the pixel electrode 141.
The subsequent steps including the hole injection / transport layer forming step are preferably an atmosphere free of water and oxygen. For example, it is preferably performed in an inert gas atmosphere such as a nitrogen atmosphere or an argon atmosphere.
[0076]
The method for forming the layer by the inkjet method is as follows.
As shown in FIG. 11, a bank 281 that partitions the pixel region 102 is formed around the pixel electrode 141, and the ejection nozzle H <b> 2 of the inkjet head H <b> 1 is disposed at the opening position of the bank 281. Then, while moving the inkjet head H <b> 1 and the substrate 121 relatively, the droplets of the first composition in which the liquid amount per droplet is controlled are ejected from the ejection nozzle H <b> 2 onto the pixel electrode 141.
[0077]
The discharged liquid droplets of the first composition spread on the electrode surface of the lyophilic pixel electrode 141 and are filled between the banks 281. In this example, since the surface (wall surface and upper surface) of the bank 281 is processed to be liquid repellent, even if the first composition deviates from the predetermined discharge position and is discharged onto the upper surface of the bank 281, The droplet of the first composition is repelled and rolls between the banks 281.
[0078]
In this example, a film forming apparatus using the above-described electromechanical conversion method (piezo method) is used as a droplet discharge device. FIG. 12 is a diagram for explaining the discharge principle of the liquid material by the piezo method. In FIG. 11, a piezo element 321 is installed adjacent to a liquid chamber 320 that stores a liquid material. The liquid material is supplied to the liquid chamber 320 via a liquid material supply system 322 including a material tank that stores the liquid material. The piezo element 321 is connected to a drive circuit 323, and a voltage is applied to the piezo element 321 via the drive circuit 323 to deform the piezo element 321, whereby the liquid chamber 320 is deformed and the liquid material is discharged from the nozzle 324. Is discharged. In this case, the amount of distortion of the piezo element 321 is controlled by changing the value of the applied voltage. Further, the strain rate of the piezo element 321 is controlled by changing the frequency of the applied voltage. Since the droplet discharge by the piezo method does not apply heat to the material, it has an advantage of hardly affecting the composition of the material.
[0079]
As the first composition, for example, a composition obtained by dissolving a mixture of a polythiophene derivative such as polyethylene dioxythiophene (PEDOT) and polystyrene sulfonic acid (PSS) in a polar solvent can be used. Examples of the polar solvent include isopropyl alcohol (IPA), normal butanol, γ-butyrolactone, N-methylpyrrolidone (NMP), 1,3-dimethyl-2-imidazolidinone (DMI) and its derivatives, carbitol acetate And glycol ethers such as butyl carbitol acetate.
[0080]
More specific composition of the first composition is, for example, PEDOT / PSS mixture: 7.25 wt%, water: 52.75 wt%, methanol: 5 wt%, IPA: 5 wt%, DMI: 50 wt% %, Γ-glycidyloxypropyltrimethoxysilane: 0.08% by weight. The viscosity of the first composition is preferably about 2 to 20 Ps. In the present invention, the composition of the first composition is not limited to the above example. In addition, as a material for forming the hole injection / transport layer, the same material may be used for each of the red (R), green (G), and blue (B) light emitting layers, or may be changed for each light emitting layer. Good.
[0081]
The discharge amount of the first composition is the size of the depression (opening) by the bank, the thickness of the hole injection / transport layer to be formed, the concentration of the hole injection / transport layer forming material in the first composition, etc. Determined by.
Further, the first composition may be disposed between the banks at a time, or may be disposed in several times. In this case, the amount of the first composition at each time may be the same, and the amount may be changed every time. Further, the first composition may be discharged from the same position to a certain pixel electrode each time, or may be discharged while shifting the position each time.
[0082]
Subsequently, as illustrated in FIG. 13, the first composition disposed on the pixel electrode 141 is dried. That is, the polar solvent contained in the first composition is evaporated to form the hole injection / transport layer 290a on the pixel electrode 141. In this example, the surface of the bank 281 (wall surface and upper surface) is processed to be liquid repellent and has a dynamic contact angle (recessed contact angle) optimal for flattening the hole injection / transport layer. , A hole injection / transport layer 290 a having a uniform thickness is formed between the banks 281.
[0083]
The drying process is performed, for example, in a nitrogen atmosphere at room temperature and a pressure of, for example, about 133.3 Pa (1 Torr). If the pressure is too low, the droplets of the first composition will boil, which is not preferable. Further, when the temperature is set to room temperature or higher, the evaporation rate of the polar solvent increases, and it is difficult to form a flat film.
Further, after the drying treatment, heat treatment may be performed by heating at 200 ° C. for about 10 minutes in nitrogen, preferably in vacuum. Thereby, the polar solvent and water remaining in the hole injection / transport layer 290a can be removed.
[0084]
(3) Light emitting layer forming step
Next, in the light emitting layer forming step, as shown in FIG. 14, as in the hole injecting / transporting layer forming step, by using a droplet discharge method (inkjet method), each color (for example, blue (B )) Including the light emitting layer forming material is discharged onto the hole injection / transport layer 290a.
[0085]
That is, the discharge nozzle H4 of the inkjet head H3 is disposed at the opening position of the bank 281 and the liquid amount per droplet is controlled from the discharge nozzle H4 while the inkjet head H3 and the substrate 121 are relatively moved. A droplet of the composition is discharged onto the hole injection / transport layer 290a.
[0086]
Examples of the light emitting layer forming material include polyfluorene polymer derivatives represented by [Chemical Formula 1] to [Chemical Formula 5], (poly) paraphenylene vinylene derivatives, polyphenylene derivatives, polyvinylcarbazole, polythiophene derivatives, perylene pigments, coumarin pigments. , Rhodamine dyes, or the above polymers can be doped with an organic EL material. For example, it can be used by doping rubrene, perylene, 9,10-diphenylanthracene, tetraphenylbutadiene, Nile red, coumarin 6, quinacridone and the like.
[0087]
The discharge amount of the second composition is determined by the size of the depression (opening) by the bank, the thickness of the light emitting layer to be formed, the concentration of the light emitting layer forming material in the second composition, and the like.
Further, the second composition may be disposed between the banks at once, or may be disposed in several times. In this case, the amount of the first composition at each time may be the same, and the amount may be changed every time. Further, the first composition may be discharged from the same position to a certain pixel electrode each time, or may be discharged while shifting the position each time.
[0088]
Subsequently, as shown in FIG. 15, the second composition disposed on the pixel electrode 141 is dried. That is, the solvent (nonpolar solvent) contained in the second composition is evaporated to form the light emitting layer 290b (the blue (B) light emitting layer 290b3) on the hole injection / transport layer 290a.
As shown in FIG. 16, red (R) and green (G) light emitting layers 290b1 and 290b2 are formed on the hole injection / transport layer 290a in the same manner as the blue light emitting layer 290b3.
In the case of the blue light-emitting layer 290b3, the drying process is performed, for example, in a nitrogen atmosphere at room temperature at a pressure of about 133.3 Pa (1 Torr) for 5 to 10 minutes. In the case of the green light-emitting layer 290b2 and the red light-emitting layer 290b1, it is preferable to dry quickly because the number of components of the light-emitting layer forming material is large. For example, when nitrogen is blown at 40 ° C. for 5 to 10 minutes Good. As other drying means, a far infrared irradiation method, a high-temperature nitrogen gas spraying method, or the like may be used.
[0089]
(4) Counter electrode (cathode) formation process
Next, in the counter electrode (cathode) formation step, a cathode 154 (counter electrode) is formed on the entire surface of the light emitting layer 290b and the bank 281 as shown in FIG.
The cathode 154 may be formed by stacking a plurality of materials. For example, it is preferable to form a material with a small work function on the side close to the light emitting layer, for example, Ca, Ba, etc. can be used, and depending on the material, it is better to form a thin layer of LiF, etc. There is also. In addition, a material having a work function higher than that of the lower side, for example, Al can be used on the upper side (sealing side).
Lithium fluoride may be formed only on the light emitting layer 290b, and can be formed corresponding to a predetermined color. For example, it may be formed only on the blue (B) light emitting layer 290b3. In this case, the upper cathode layer made of calcium is in contact with the other red (R) light-emitting layers and green (G) light-emitting layers 290b1 and 290b2.
These cathodes 154 can be formed by using, for example, a vapor deposition method, a sputtering method, a CVD method, or the like. In this example, a vapor deposition method is used to prevent damage to the light emitting layer 290b due to heat.
Further, an Al film, an Ag film, or the like is preferably used on the cathode 154. The thickness is preferably in the range of, for example, 100 to 1000 nm, particularly about 200 to 500 nm.
Further, a protective layer such as SiO 2 or SiN may be provided on the cathode 154 to prevent oxidation.
[0090]
Through the above steps, the light emitting portion 140 is formed on the substrate 121, and an organic EL element is formed. Thereafter, the substrate 121 on which the organic EL element is formed is sealed, the cathode 154 is connected to the wiring of the substrate 121, and the wiring of the circuit element unit 146 is connected to a driving IC (driving circuit) provided on or outside the substrate 121. By connecting these, an organic EL display device is completed.
[0091]
18A to 18C show an embodiment of an electronic device according to the present invention.
The electronic apparatus of this example includes the electro-optical device of the present invention such as the organic EL display device described above as a display unit.
FIG. 18A is a perspective view showing an example of a mobile phone. In FIG. 18A, reference numeral 600 indicates a mobile phone body, and reference numeral 601 indicates a display unit using the display device.
FIG. 18B is a perspective view illustrating an example of a portable information processing apparatus such as a word processor or a personal computer. In FIG. 18B, reference numeral 700 denotes an information processing apparatus, reference numeral 701 denotes an input unit such as a keyboard, reference numeral 703 denotes an information processing apparatus body, and reference numeral 702 denotes a display unit using the display device.
FIG. 18C is a perspective view illustrating an example of a wristwatch type electronic device. In FIG. 18C, reference numeral 800 denotes a watch body, and reference numeral 801 denotes a display unit using the display device.
Since each of the electronic devices shown in FIGS. 18A to 18C includes the electro-optical device of the present invention as a display unit, display with excellent quality can be realized.
[0092]
As mentioned above, although the suitable Example concerning this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to the example which concerns. Various shapes, combinations, and the like of the constituent members shown in the above-described examples are examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.
[0093]
【Example】
A substrate on which a bank made of acrylic resin was formed and a flat substrate made of the same acrylic resin as the bank were prepared, and the above-described CF4 plasma treatment was performed on each substrate. The processing time was changed between 1.0 and 6.6 sec.
In addition, after the CF4 plasma treatment, the above-described droplet material for the hole injection / transport layer is discharged to the substrate on which the bank is formed, and the hole injection / transport layer is formed in a region partitioned by the bank. The film thickness profile was measured. The composition of the liquid material was as follows: PEDOT / PSS mixture: 7.25 wt%, water: 52.75 wt%, methanol: 5 wt%, IPA: 5 wt%, DMI: 50 wt%, γ-glycidyloxypropyltri Methoxysilane: 0.08% by weight. The droplet material was dried at 200 ° C. for 10 minutes after drying under reduced pressure.
[0094]
As a result, the most ideal film thickness profile was obtained when the processing time was 1.17 to 1.4 sec. If the treatment time is less than 1.17 sec, the liquid repellency becomes insufficient and the film thickness near the wall surface of the bank becomes thick, which is not preferable. If it exceeds 1.4 sec, the liquid repellency becomes too high, This is not preferable because the film thickness near the wall surface becomes thin.
[0095]
On the other hand, after the CF4 plasma treatment on the flat substrate, using the CA-W contact angle measurement device manufactured by Kyowa Interface Science Co., Ltd., the movement of the liquid material is performed according to the measurement method described with reference to FIG. The static contact angle (recessed contact angle) and the static contact angle were measured. The θ / 2 method was used for the measurement of the static contact angle. The results are shown below.

[0096]
From the above results, it was confirmed that the treatment conditions for liquid repellency can be managed by using the dynamic contact angle (backward contact angle) as an index. That is, an ideal and flat film thickness profile can be obtained by managing the plasma processing conditions so that the dynamic contact angle (recessed contact angle) is in the range of about 29 ° to 45 °. It was confirmed. On the other hand, it was found that the above management is difficult with a static contact angle.
[0097]
【The invention's effect】
According to the method and apparatus for manufacturing an electro-optical device of the present invention, when processing the surface of the bank to make it liquid repellent, by using the dynamic contact angle as an index, the liquid repellent processing condition for the flattening of the film Is surely optimized. Therefore, a flat film can be easily and stably formed in the region partitioned by the bank.
[0098]
Further, according to the electro-optical device of the present invention, the structure of the organic EL element can be optimized and the performance can be improved.
[0099]
According to the electronic apparatus of the present invention, since the electro-optical device is provided as a display unit, the performance of the display unit can be improved.
[Brief description of the drawings]
FIG. 1 is a diagram conceptually illustrating a method for manufacturing an organic EL device as an electro-optical device of the present invention.
FIG. 2 is a diagram illustrating a measurement example of a dynamic contact angle (retreat contact angle).
FIG. 3 is a diagram schematically showing an embodiment of an apparatus for manufacturing an organic EL device as an electro-optical device of the invention.
FIG. 4 is a diagram schematically showing a configuration of an organic EL display device which is an embodiment of the electro-optical device of the invention.
FIG. 5 is an enlarged view of a cross-sectional structure in the vicinity of a pixel region in an organic EL display device.
FIG. 6 is a diagram schematically showing an example of a planar structure of a bank.
FIG. 7 is a diagram schematically illustrating a configuration example of a plasma processing apparatus.
FIG. 8 is a diagram schematically showing a configuration example of a plasma processing chamber.
FIG. 9 is a process diagram illustrating a method for manufacturing an organic EL device.
FIG. 10 is a process diagram illustrating a method for manufacturing an organic EL device.
FIG. 11 is a diagram for explaining the principle of droplet discharge by a piezo method.
FIG. 12 is a process diagram illustrating a method for manufacturing an organic EL device.
FIG. 13 is a process diagram illustrating a method for manufacturing an organic EL device.
FIG. 14 is a process diagram illustrating a method for manufacturing an organic EL device.
FIG. 15 is a process diagram illustrating a method for manufacturing an organic EL device.
FIG. 16 is a process diagram illustrating a method for manufacturing an organic EL device.
FIG. 17 is a process diagram illustrating a method for manufacturing an organic EL device.
FIG. 18 is a diagram illustrating an embodiment of an electronic apparatus according to the invention.
FIG. 19 is a schematic cross-sectional view showing a typical configuration of a main part of an organic EL display device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10,281 ... Bank, 12 ... Film, 20 ... Organic EL device manufacturing device (electro-optical device manufacturing device), 21 ... Liquid repellent device, 22 ... Measuring device, 23 ... Film forming device, 24 ... Control device, 100 ... Organic EL display device, 102 ... Pixel region, 121 ... Substrate, θ ... Dynamic contact angle (retraction contact angle).

Claims (5)

In an electro-optical device manufacturing method including a step of forming a film by disposing a liquid material in an area partitioned by a bank,
A liquid repellent step of processing the surface of the bank to be liquid repellent by plasma treatment before the liquid material is disposed ;
A measuring step of measuring a dynamic contact angle of the object made of the same material as the bank with respect to the liquid material;
And determining a processing condition of the liquid repellency step from the measurement result of the measurement step ,
In the liquid repellency step, the dynamic contact angle is measured as needed, and the processing conditions are managed so as not to deviate from a target value . Wherein the lyophobic process, the as receding contact angle of the dynamic contact angle is in the range of 29 ° to 45 °, the electro-optical device according to claim 1, characterized in that managing the processing condition Manufacturing method.   The method of manufacturing an electro-optical device according to claim 1, further comprising a lyophilic step of processing the surface of the bank to be lyophilic before the lyophobic step. . In an electro-optical device manufacturing apparatus including a film forming apparatus that forms a film by arranging a liquid material in a region partitioned by a bank,
A lyophobic device for processing the surface of the bank to be lyophobic by plasma treatment ;
A measuring device for measuring a dynamic contact angle of an object made of the same material as the bank with respect to the liquid material ;
A control device for determining processing conditions of the lyophobic device from the measurement result of the measuring device ,
The electro-optical device manufacturing apparatus, wherein the lyophobic device is processed based on the processing conditions .   The electro-optical device manufacturing apparatus according to claim 4, further comprising a lyophilic device that processes the bank surface to be lyophilic before the surface of the bank is processed to be lyophobic.

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