JP4582991B2 - Method for producing transparent conductive substrate for organic EL display device - Google Patents

Description

表１の結果より、本発明にかかる透明導電膜は、大気圧又は大気圧近傍の圧力下において、ハイパワー（１００ｋＨＺを越える高周波電圧、１Ｗ／ｃｍ²以上の電力）で形成されるので、比較例１及び２のローパワーで形成する場合に比して、低抵抗で、かつ、光透過率に優れることが確認された。
【０１１３】
次に、以下に示す実施例７、８、比較例３の透明導電膜を作成した。
【０１１４】
［本発明の実施例７］
（放電出力条件）
５Ｗ／ｃｍ²
（ガス条件）
放電ガス：ヘリウム…９８．７４体積％
反応性ガス１：水…０．０１体積％
反応性ガス２：インジウムアセチルアセトナト…１．２体積％
反応性ガス３：ジブチル錫ジアセテート…０．０５体積％
なお、（基材）としては実施例６と同様のものを使用し、（プラズマ電源周波数とメーカー）、（電極）としては、実施例１と同様の条件で、大気圧プラズマ処理を行い、基材上にＩＴＯ膜を作成した。
【０１１５】
［本発明の実施例８］
（ガス条件）
放電ガス：ヘリウム…９８．６０体積％
反応性ガス１：水素…０．１５体積％
反応性ガス２：インジウムアセチルアセトナト…１．２体積％
反応性ガス３：ジブチル錫ジアセテート…０．０５体積％
なお、（電極）としては、実施例１と同様のものを使用し、（基材）、（プラズマ電源周波数とメーカー）、（放電出力条件）は実施例７と同様の条件で、大気圧プラズマ処理を行い、基材上にＩＴＯ膜を作成した。
【０１１６】
［比較例３］
特開２０００−３０３１７５号公報の実施例３記載の方法を用いて以下のように透明導電膜を形成した。
（ガス条件）
放電ガス：ヘリウム…９８．７５体積％
反応性ガス１：水素…０．５体積％
反応性ガス２：インジウムアセチルアセトナト…１．２体積％
反応性ガス３：ジブチル錫ジアセテート…０．０５体積％
なお、（基材）としては実施例７と同様の条件で、（プラズマ電源周波数とメーカー）、（放電出力条件）としては比較例１と同様の条件で、（電極）としては、実施例１と同様のものを使用し、大気圧プラズマ処理を行い、基材上にＩＴＯ膜を作成した。
【０１１７】
そして、これら本発明の実施例７、８、比較例３によって作成した透明導電膜に対して、上述したダイナミックＳＩＭＳ測定により水素イオンと主金属元素イオンのピーク強度比Ｈ／Ｍの深さ方向における変動係数を求め、その結果を表２に示した。また、抵抗率、光透過率の評価についても表２に示した。
【０１１８】
【表２】

表２の結果より、本発明の有機ＥＬ表示装置用透明導電性基材の透明導電膜のピーク強度比Ｈ／Ｍの変動係数５％以内とすることによって、透明導電膜の性能がさらに向上することが認められた。
【０１１９】
また、上述した本発明の実施例１〜８、比較例１〜３によって作成した透明導電膜が形成された基材を用いて、以下に示す方法で単純マトリックス駆動有機ＥＬ素子を作成した。
（有機ＥＬ素子の作成方法）
まず、電極をパターニングした。その後、中性洗剤、アセトン、エタノールを用いて超音波洗浄し、次いで煮沸エタノール中から引き上げ乾燥した。次いで、透明導電膜表面をＵＶ／Ｏ₃洗浄した後、真空蒸着装置でＮ，Ｎ’−ジフェニル−ｍ−トリル−４，４’−ジアミン−１，１’−ビフェニル（ＴＰＤ）を蒸着速度０．２ｎｍ／ｓｅｃで５５ｎｍの厚さに蒸着し、正孔注入輸送層とした。
さらに、Ａｌｑ3：トリス（８−キノリノラト）アルミニウムを蒸着速度０．２ｎｍ／ｓｅｃで５０ｎｍの厚さに蒸着して、電子注入輸送・発光層とした。
次いで、スパッタ装置でＤＣスパッタ法にてＡｌ・Ｓｍ合金（Ｓｍ：１０at%）をターゲットとして陰電極を２００ｎｍの厚さに製膜した。この時のスパッタガスにはＡｒを用い、ガス圧３．５Ｐａ、ターゲットと基板間距離（Ｔｓ）９．０ｃｍとした。また、投入電力は１．２Ｗ／ｃｍ²とした。
最後に、ＳｉＯ₂を２００ｎｍの厚さにスパッタして保護層として、有機ＥＬ発光素子を得た。この有機ＥＬ発光素子は、それぞれ２本ずつの平行ストライプ状陰電極と、８本の平行ストライプ状用電極を互いに直交させ、２×２ｍｍ縦横の素子単体（画素）を互いに２ｍｍの間隔で配置し、８×２の１６画素の素子としたものである。
【０１２０】
このようにして得られた有機ＥＬ素子についてダークスポットの発生の有無について観測した。
《ダークスポット数評価》
６０℃、９５％ＲＨの雰囲気下で、１週間処理後のダークスポット数を調べた。評価方法として、ダークスポットが観測されない場合に◎、１０ｍｍ角の領域にダークスポット５箇所未満の場合に○、１０ｍｍ角の領域にダークスポット５箇所以上の場合に×とし、その結果を表３に示した。
【０１２１】
【表３】

表３の結果より、本発明の実施例１〜８はダークスポットが発生しないことが認められた。
【０１２２】
さらに、得られた有機ＥＬ素子を９Ｖで駆動させたところ、実施例１では３５０ｃｄ／ｍ²の輝度が得られたが、比較例１〜３では５０ｃｄ／ｍ²以下であり、有機ＥＬ素子としての必要な発光強度が得られなかった。
【０１２３】
なお、実施例１の基材のみを以下のものに変更して、その他同様の条件下で基材上に透明導電膜であるＩＴＯ膜を形成したところ、これら透明導電膜からは実施例１と同等の性能が得られた。
基材として、ポリエーテルスルフォン（ＰＥＳ）（例えば、住友ベークライト（株）製 スミライト ＦＳ−１３００）、有機無機ハイブリッド基材を使用する。
【０１２４】
また、有機無機ハイブリッド基材は、次のようにして作成した。
（セルロース１の作成）
Ｊ．Ａｐｐｌ．Ｐｏｌｙｍ．Ｓｃｉ．，５８，１２６３−１２７４（１９９５）に記載の合成法を参考に合成を行った。ジアセチルセルロース（ダイセル化学工業製、酢酸セルロースＬ−５０、以下ＤＡＣと略）３６．９３ｇを、脱水テトラヒドロフラン（以下ＴＨＦと略）２５８．５４ｇに６０℃に加熱還流・攪拌しながら溶解させ、３−イソシアナートプロピルトリエトキシシラン（以下ＩＰＴＥＳと略）３．７２ｇを滴下し、さらに触媒として二ラウリン酸ジブチルスズを脱水ＴＨＦで１０質量％に調整した溶液を２．８５ｇ滴下し、そのまま５時間加熱還流しながら攪拌した。５時間後に溶液の赤外吸収スペクトルを測定すると、ＩＰＴＥＳのイソシアナート基に由来する、２２７１ｃｍ―¹の吸収が消失していることが確認できたため、加熱を止めて放冷し、３Ｌのヘキサン中に注いで再沈殿させ、４０．５０ｇの白色固定を得た（収率９９．６％）。得られた白色固定の²⁹Ｓｉ−ＮＭＲスペクトルを測定したところ、―４５．２５ｐｐｍに単一の吸収が見られた。また、¹³Ｃ−ＮＭＲスペクトルを測定したところ、１６３．０７ｐｐｍにアミドカルボニルの吸収が見られ、目的のセルロース１が得られていることを確認した。
（基材フィルム１の作成）
得られたセルロース１の２０．０ｇを脱水ＴＨＦ１８０ｇに溶解させ、セルロース１の１０％溶液を作成した。
そして、３０ｍｌのビーカー中に、セルロース１の１０％溶液を３．６５ｇを、テトラエトキシシラン（以下ＴＥＯＳと略）０．４１ｇ、０．２５％希塩酸を０．１４ｇを加え、８分間室温で攪拌し、直径７．５ｃｍのフッ素樹脂製のシャーレに撒き、軽くフタをして２日間室温で放置した。２日後に溶媒がほぼ揮発したところで３０分間真空ポンプで乾燥させ、無色透明の基材フィルム１を得た。乾燥後の厚みは１００μｍであった。
【０１２５】
【発明の効果】
本発明の有機ＥＬ表示装置用透明導電性基材によれば、低抵抗で、かつ、光透過性や表面平滑性に優れ、また、十分な発光強度を得ることができ、ダークスポットが発生しにくい。
【図面の簡単な説明】
【図１】本発明の透明導電膜を形成するために用いられるプラズマ放電処理装置に設置されるプラズマ放電処理容器の一例を示す概略図である。
【図２】プラズマ放電処理容器の他の一例を示す概略図である。
【図３】円筒型のロール電極の一例を示す斜視図である。
【図４】固定型の円筒型電極の一例を示す斜視図である。
【図５】固定型の角柱型電極の一例を示す斜視図である。
【図６】プラズマ放電処理装置の一例を示す概略図である。
【図７】プラズマ放電処理装置の他の一例を示す概略図である。
【図８】有機ＥＬ素子の構成例を示す概念図である。
【符号の説明】
Ｆ フィルム（基材）
Ｌ レンズ（基材）
１０、１００ プラズマ放電処理装置
２１、２２ 電極（ロール電極）
２９ 電極（固定電極）
５０、１１０ 電源
１２０ 電極
１２１ 上側平板電極
１２２ 下側平板電極[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a transparent conductive substrate for an organic EL display device, in which a transparent conductive film is formed on the surface, and particularly used in an organic EL display device.
[0002]
[Prior art]
In recent years, organic EL display devices have attracted attention as elements for full-color flat panel displays. In the organic EL display device, for example, as shown in FIG. 8, a hole injection transport layer 203 and a light emitting layer 204 made of an organic material are formed on a transparent conductive film (positive electrode) 202 formed on a glass substrate 201, respectively. Further, a negative electrode 205 and a protective layer 206 are formed thereon. A low voltage is applied between the positive electrode 202 and the negative electrode 205.
[0003]
The transparent conductive film used in such an organic EL display device is, for example, a wet film formation method represented by coating, or a dry film formation using a vacuum such as a sputtering method, a vacuum deposition method, or an ion plating method. Formed by law.
Coating is useful in terms of high productivity, but since the material constituting the transparent conductive film must be a coating solution dissolved or dispersed in the solvent, the solvent remains in the transparent conductive film, It cannot be said that it is suitable for forming a high-performance transparent conductive film because it is difficult to maintain uniformity. Moreover, since a coating uses a binder, a low-resistance transparent conductive film cannot be obtained. Further, there is a problem that a solvent such as an organic solvent evaporated from the coating solution in the drying step after coating gives a load to the environment.
On the other hand, in the dry film forming method using vacuum, the vacuum deposition method and the ion plating method cannot obtain a low resistance transparent conductive film, and the sputtering method can obtain a low resistance transparent conductive film. In both cases, the larger the substrate to be treated, the larger the size of the vacuum device used, which increases the price, and the demerit that it takes a lot of time for evacuation and the productivity cannot be increased. In addition, the sputtering method has a problem that the target is expensive, and furthermore, if it is used by several tens of percent, replacement is necessary, so that the use efficiency is low.
[0004]
Therefore, as a method of overcoming the disadvantages of being difficult to obtain a high-performance transparent conductive film and the disadvantages of low productivity and high costs due to the use of a vacuum apparatus, the reactive gas is discharged under atmospheric pressure or near atmospheric pressure. A method (atmospheric pressure plasma method) for forming a transparent conductive film on a substrate by plasma excitation is described in, for example, Japanese Patent Application Laid-Open Nos. 2000-303175 and 2001-74906. The atmospheric pressure plasma method disclosed in these publications generates discharge plasma by applying an electric field having a frequency of 0.5 kHz to 100 kHz and an electric field strength of 1 to 100 kV / cm between opposed electrodes. It is to let you.
[0005]
[Problems to be solved by the invention]
By the way, when using a substrate on which such a transparent conductive film is formed for an organic EL display device, it should have low resistance, excellent light transmission and surface smoothness, and sufficient light emission intensity. Is required. In particular, in a plastic organic EL display element, a base material that generates less dark spots is required.
However, the atmospheric pressure plasma method forms a transparent conductive film under atmospheric pressure and is therefore excellent in productivity and inexpensive, but is insufficient in terms of the resistance value, light transmittance, surface smoothness, and emission intensity described above. In addition, dark spots were likely to occur.
The present invention has been made in view of the above circumstances, and is an organic EL that has low resistance, is excellent in light transmittance and surface smoothness, can obtain sufficient light emission intensity, and hardly generates dark spots. It is an object to provide a method for producing a transparent conductive substrate for a display device.
[0006]
[Means for Solving the Problems]
In order to solve the above problems, the invention of claim 1 is a method for producing a transparent conductive substrate for an organic EL display device in which a transparent conductive film is formed on a substrate,
Under atmospheric pressure or a pressure of 20 kPa to 110 kPa, a discharge gas and a reactive gas are introduced, and a high frequency voltage exceeding 100 kHz is applied between electrodes arranged to face each other so as to form a discharge space, and 1 W / cm. ^The transparent conductive film containing either ITO or IZO by bringing the reactive gas into a plasma state by supplying and discharging ^two or more electric powers, and exposing the substrate to the reactive gas in the plasma state Form the
The reactive gas contains a reducing gas .
[0008]
Invention of Claim 2 in the manufacturing method of the transparent electroconductive base material for organic electroluminescent display devices of Claim 1 ,
At least one intermediate layer is interposed between the substrate and the transparent conductive film.
[0009]
Invention of Claim 3 in the manufacturing method of the transparent electroconductive base material for organic electroluminescent display apparatuses of Claim 2 ,
The intermediate layer contains an inorganic oxide.
[0014]
A fourth aspect of the present invention, in the manufacturing method of the organic EL display device transparent conductive substrate according to any one of claims 1 to 3
A gas barrier layer is formed on the surface of the transparent conductive film.
[0015]
Invention of Claim 5 in the manufacturing method of the transparent electroconductive base material for organic electroluminescent display apparatuses of any one of Claims 1-4 ,
The base material is glass.
[0016]
Invention of Claim 6 in the manufacturing method of the transparent electroconductive base material for organic electroluminescent display apparatuses of any one of Claims 1-5 ,
The base material is a plastic film.
[0017]
Invention of Claim 7 in the manufacturing method of the transparent electroconductive base material for organic electroluminescent display devices of Claim 6 ,
The plastic film contains a polyester resin.
[0022]
Invention of Claim 8 in the manufacturing method of the transparent conductive base material for organic electroluminescent display apparatuses of any one of Claims 1-7 ,
The transparent conductive film is characterized in that variation in the depth direction of the peak intensity ratio H / M between hydrogen ions and main metal element ions by dynamic SIMS measurement is within 5%.
[0023]
Here, H is the intensity of the hydrogen ion peak, and M is the peak intensity of the main metal element ion.
[0027]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below.
The transparent conductive substrate for an organic EL display device of the present invention is formed by forming a transparent conductive film on a substrate, and the transparent conductive film is formed between the opposing electrodes under atmospheric pressure or pressure near atmospheric pressure. The high-frequency voltage exceeding 100 kHz and the power (power density) of 1 W / cm ² or more are supplied and discharged to excite the reactive gas into a plasma state, and the substrate is in the plasma state. Formed by exposure to reactive gases.
[0028]
In the present invention, the transparent conductive film is generally well known as an industrial material and is a transparent film that absorbs almost no visible light (400 to 700 nm) and is transparent. Since the free charged material carrying electricity has high transmission characteristics in the visible light region, is transparent, and has high electrical conductivity, it is used as a transparent electrode for organic EL display devices and the like. When the transparent conductive film is used for an organic EL display device as in the present invention, the thickness of the transparent conductive film is preferably about 100 to 140 nm.
[0029]
As the transparent conductive film, a composite oxide with a metal oxide film such as SnO ₂ , In ₂ O ₃ , CdO, ZnO ₂ , SnO ₂ : Sb, SnO ₂ : F, ZnO: AL, In ₂ O ₃ : Sn, and a dopant is used. There is a material film.
Examples of the composite oxide film using a dopant include an ITO film obtained by doping tin with indium oxide, an FTO film obtained by doping fluorine with tin oxide, an IZO film made of In ₂ O ₃ —ZnO-based amorphous material, and the like. Is mentioned.
[0030]
Moreover, it is preferable that at least one intermediate layer is interposed between the substrate and the transparent conductive film. Examples of the intermediate layer include an ultraviolet curable resin layer and a silica layer that is an inorganic oxide. For example, when the base material is glass, this intermediate layer functions as an alkali barrier layer that prevents alkali metal from diffusing from the glass. When the base material is plastic, it has an effect of improving adhesion and reducing plasma damage.
Thus, by providing the intermediate layer, the characteristics of the transparent conductive film can be improved as compared with the case where the transparent conductive film is formed directly on the substrate. Moreover, the adhesiveness between a base material and a transparent conductive film can be improved by this intermediate | middle layer.
For the intermediate layer, it is preferable to use a material having a lattice constant close to that of the base material and the transparent conductive film. When the base material is glass, it is preferable to use a silica layer as the intermediate layer.
[0031]
In the present invention, the upper limit of the frequency of the high-frequency voltage applied between the electrodes is preferably 150 MHz or less. Further, the lower limit value of the frequency of the high frequency voltage is preferably 200 kHz or more, and more preferably 800 kHz or more.
The lower limit value of the power supplied between the electrodes is preferably 1.2 W / cm ² or more, and the upper limit value is preferably 50 W / cm ² or less, more preferably 20 W / cm ² or less. The discharge area (/ cm ² ) refers to an area in a range where discharge occurs in the electrode. When a high power voltage is applied at a high frequency and a high output density as in the present invention, this corresponds to the total area of the discharge surface of the electrode on one side. By dividing the total power (W) supplied from the power source connected to the electrode by this total area, the output density can be calculated.
[0032]
In order to obtain a uniform film thickness particularly in a large area, the total power applied to a pair of opposing electrodes is preferably more than 15 kW, more preferably 30 kW or more, and further preferably 50 kW or more. From the viewpoint of heat generation, it is preferably 300 kW or less. The total power corresponds to the power (W) supplied from the power source connected to the set of electrodes. When two or more power sources are connected to the set of electrodes, the value is a value obtained by adding the power supplied to all the power sources.
[0033]
Specifically, in the plasma discharge processing apparatus of FIG. 6 described later, the roll electrode 21 and the prismatic electrode group 29 are used as a pair of opposed electrodes, and the power is supplied from the power supply 50 connected thereto. . In FIG. 6, when the surface of the prismatic electrode 29 facing the roll electrode 21 is the discharge surface on the application electrode side, the total area of the discharge surface is the discharge area. When the electrode is a cylindrical electrode 22 as shown in FIG. 1, the sum of the projected areas of the cylindrical electrode 22 onto the roll electrode 21 is the discharge area.
[0034]
The high-frequency voltage applied between the electrodes may be an intermittent pulse wave or a continuous sine wave. However, in order to obtain the effect of the present invention, it is a continuous sine wave. It is preferable.
[0035]
By applying a high-power electric field as described above over a large area, it is possible to obtain a high-performance transparent conductive film that is dense, highly uniform in film thickness, and has no unevenness with high production efficiency. Have been found by the present inventors. The inventors presume that this excellent effect is due to the fact that high-density plasma can be generated uniformly over a large area by adopting the above discharge method.
In the present invention, a high durability electrode that can maintain a uniform discharge state even when such a high-power electric field is applied to an electrode having a large area under atmospheric pressure or near atmospheric pressure is plasma-discharged. It is necessary to employ in the processing equipment.
[0036]
As such an electrode, it is preferable that at least a discharge surface on a conductive base material such as metal is coated with a dielectric. At least one of the opposing application electrode and ground electrode is coated with a dielectric, and preferably both the application electrode and ground electrode are coated with a dielectric.
[0037]
A dielectric coated electrode is a composite part of a conductive base material such as metal and a dielectric material such as ceramics or glass. When the supplied power, especially when the total power is large, it breaks down from the vulnerable part of the dielectric. It is difficult to maintain a stable plasma discharge. This is particularly noticeable in a dielectric coated electrode having a large discharge area. In order to form a transparent conductive film using high power according to the present invention, a dielectric coated electrode that can withstand it is required.
[0038]
Specifically, the dielectric used in the dielectric-coated electrode according to the present invention is preferably an inorganic compound having a relative dielectric constant of 6 to 45, and examples of such a dielectric include alumina, nitridation. There are ceramics such as silicon, or glass lining materials such as silicate glass and borate glass. In this, what sprayed the ceramics mentioned later and the thing provided by glass lining are preferable. In particular, a dielectric provided by spraying alumina is preferable.
[0039]
In the dielectric-coated electrode, as one of the specifications that can withstand the above-described high power, the dielectric porosity is 10 volume% or less, preferably 8 volume% or less. Preferably it is more than 0 volume% and 5 volume% or less. The porosity of the dielectric means a porosity that is penetrable in the thickness direction of the dielectric, and can be measured with a mercury porosimeter. High durability is achieved because the dielectric has a low porosity. Examples of the dielectric having such a void and having a low void ratio include a high-density, high-adhesion ceramic spray coating by the atmospheric plasma method described later. In order to further reduce the porosity, it is preferable to perform sealing treatment.
[0040]
As another preferable specification of the dielectric-coated electrode, a dielectric is formed by a glass lining method using glass obtained by a melting method. The dielectric at this time is more durable if it is composed of two or more layers having different amounts of mixed bubbles. As the amount of bubbles mixed in, the lowermost layer in contact with the conductive base material is preferably 20 to 30% by volume, and the subsequent layers are preferably 5% or less by volume. The amount of bubbles mixed in can be calculated from the relationship between the intrinsic density of the glass itself and the density of the glass lining layer. As a method of controlling the amount of bubbles mixed into the glass, since the bubbles are originally mixed in the glass melt, deaeration is performed, but a desired value can be obtained by changing the degree of deaeration. A highly durable electrode can also be obtained by controlling the amount of bubbles mixed in and a dielectric material by a glass lining method provided in layers. In addition, the total thickness of the dielectric layer at this time is 0.5 mm or more and 2.0 mm or less, the film thickness of the lowermost layer is 0.1 mm or more, and the total film thickness after the next layer is 0.3 mm or more. Is preferred.
[0041]
In addition, in the dielectric-coated electrode according to the present invention, another preferred specification that can withstand high power is that the heat-resistant temperature is 100 ° C. or higher. More preferably, it is 120 degreeC or more, Most preferably, it is 150 degreeC or more. The heat-resistant temperature refers to the highest temperature that can withstand normal discharge without breakdown. Such heat-resistant temperature is applied within the range of the difference in linear thermal expansion coefficient between the conductive base material and the dielectric below, by applying the ceramics sprayed above and the dielectric material provided with layered glass lining with different foam mixing amount. This can be achieved by appropriately combining means for appropriately selecting the materials.
[0042]
In addition, in the dielectric-coated electrode according to the present invention, another preferable specification is a combination in which the difference in linear thermal expansion coefficient between the dielectric and the conductive base material is 10 × 10 ⁻⁶ / ° C. or less. . It is preferably 8 × 10 ⁻⁶ / ° C. or less, more preferably 5 × 10 ⁻⁶ / ° C. or less, and further preferably 2 × 10 ⁻⁶ / ° C. or less. The linear thermal expansion coefficient is a well-known physical property value of a material.
As a combination of a conductive base material and a dielectric whose linear thermal expansion coefficient is within this range,
(1) Conductive base material is pure titanium, dielectric is ceramic sprayed coating (2) Conductive base material is pure titanium, dielectric is glass lining (3) Conductive base material is titanium alloy, dielectric is Ceramic sprayed coating (4) Conductive base material is titanium alloy, dielectric is glass lining (5) Conductive base material is stainless steel, dielectric is ceramic sprayed coating (6) Conductive base material is stainless steel, dielectric Is a glass lining (7) conductive matrix is a ceramic and iron composite, dielectric is a ceramic spray coating (8) conductive matrix is a ceramic and iron composite, and dielectric is a glass lining (9) The base material is a composite material of ceramics and aluminum, the dielectric is a ceramic spray coating (10) The conductive base material is a composite material of ceramics and aluminum, and the dielectric is glass lining, etc. From the viewpoint of the difference in linear thermal expansion coefficient, the above (1) to (4) and (7) to (10) are preferable.
[0043]
In addition, in the dielectric-coated electrode according to the present invention, another preferable specification that can withstand high power is that the thickness of the dielectric is 0.5 to 2 mm. The film thickness variation is desirably 5% or less, preferably 3% or less, and more preferably 1% or less.
An example of a method for thermally spraying the conductive base material with high density and high adhesion using ceramic as a dielectric material is an atmospheric plasma spraying method. The atmospheric plasma spraying method is a technique in which a fine powder such as ceramics, a wire, or the like is put into a plasma heat source and sprayed on a base material to be coated as fine particles in a molten or semi-molten state to form a film. A plasma heat source is a high-temperature plasma gas in which a molecular gas is heated to a high temperature, dissociated into atoms, and energy is given to emit electrons. The plasma gas injection speed is high, and since the sprayed material collides with the base material at a higher speed than conventional arc spraying or flame spraying, it is possible to obtain a coating film with high adhesion strength and high density. Specifically, reference can be made to a thermal spraying method for forming a heat shielding film on a high-temperature exposed member described in JP-A No. 2000-301655. According to this method, the porosity of the dielectric (ceramic sprayed film) to be coated can be 10% by volume or less, and further 8% by volume or less.
[0044]
In order to further reduce the porosity of the dielectric, it is preferable to further seal the sprayed film such as ceramic with an inorganic compound. As the inorganic compound, a metal oxide is preferable, and among these, a compound containing silicon oxide (SiOx) as a main component is particularly preferable.
[0045]
The inorganic compound for sealing treatment is preferably formed by curing by a sol-gel reaction. In the case where the inorganic compound for sealing treatment contains a metal oxide as a main component, a metal alkoxide or the like is applied as a sealing liquid on the ceramic sprayed film and cured by a sol-gel reaction. When the inorganic compound is mainly composed of silica, it is preferable to use alkoxysilane as the sealing liquid.
Here, it is preferable to use energy treatment for promoting the sol-gel reaction. Examples of the energy treatment include thermosetting (preferably 200 ° C. or less), UV irradiation, and the like. Furthermore, as a method of sealing treatment, when the sealing liquid is diluted and coating and curing are repeated several times in succession, the mineralization is further improved and a dense electrode without deterioration can be obtained.
[0046]
When a ceramic sprayed coating is applied to a ceramic sprayed film using a metal alkoxide or the like of a dielectric-coated electrode as a sealing liquid, the content of the metal oxide after curing is 60 mol% or more when cured by a sol-gel reaction. Preferably there is. When alkoxysilane is used as the metal alkoxide of the sealing liquid, the cured SiOx content (x is 2 or less) is preferably 60 mol% or more. The SiOx content after curing is measured by analyzing a fault of the dielectric layer by XPS.
[0047]
Further, the surface roughness Rmax (JIS B 0601) of the electrode is reduced to 10 μm or less by a method such as polishing the dielectric surface of the dielectric coated electrode, so that the thickness of the dielectric and the gap between the electrodes are made constant. It can be maintained, the discharge state can be stabilized, distortion and cracking due to thermal shrinkage difference and residual stress can be eliminated, and durability can be greatly improved with high accuracy. The polishing finish of the dielectric surface is preferably performed at least on the dielectric in contact with the substrate.
[0048]
Next, a plasma discharge processing apparatus using such an electrode will be described with reference to FIGS. The plasma discharge treatment apparatus of FIGS. 1-6 discharges between the roll electrode which is an earth electrode, and the some fixed electrode which is an application electrode arrange | positioned in the position which opposes, and reactive gas is made between the said electrodes. A thin film (transparent conductive film) is formed by introducing a plasma state and exposing the long film-like substrate wound around the roll electrode to the reactive gas in the plasma state. Here, in the width direction orthogonal to the substrate transport direction, the length of the electrode is the same as the length of the long film. After forming the thin film, assuming that the end of the long film in the width direction is cut, if the area where the thin film is formed is shorter than the width of the long film, the area where the thin film is formed The same length of the discharge surface of the electrode may be the same or longer than the length of the electrode.
[0049]
The plasma discharge treatment apparatus for forming the transparent conductive film of the present invention is not limited to this, and the plasma state is obtained by exciting the reactive gas to stably maintain the glow discharge and form the transparent conductive film. However, the method of placing the base material between the electrodes and introducing the reactive gas between the electrodes can take a large discharge area and make the film thickness uniform. In addition, a high-performance transparent conductive film can be formed, which is preferable.
[0050]
FIG. 1 is a schematic view showing an example of a plasma discharge treatment vessel 20 of a plasma discharge treatment apparatus 10 used when forming a transparent conductive film of the present invention. In the present embodiment, the plasma discharge treatment shown in FIG. A container 20 is used.
In FIG. 1, a long film-like substrate F is conveyed while being wound around a roll electrode 21 that rotates in the conveying direction (clockwise in the figure). The fixed electrode 22 is composed of a plurality of cylinders, and is installed facing the roll electrode 21. The substrate F wound around the roll electrode 21 is pressed by the nip rollers 23a and 23b, is regulated by the guide roller 24, is transported to the discharge treatment space secured by the plasma discharge treatment vessel 20, is subjected to discharge plasma treatment, and then Then, it is conveyed to the next process via the guide roller 25. Further, the partition plate 26 is disposed in the vicinity of the nip roller 23b and suppresses the air accompanying the base material F from entering the plasma discharge processing container 20.
[0051]
The entrained air is preferably suppressed to 1% by volume or less, and more preferably 0.1% by volume or less, with respect to the total volume of the gas in the plasma discharge treatment vessel 20. This can be achieved by the nip roller 23b.
A mixed gas (discharge gas and reactive gas) used for the discharge plasma treatment is introduced into the plasma discharge treatment container 20 from the air supply port 27, and the treated gas is exhausted from the exhaust port 28.
[0052]
FIG. 2 is a schematic view showing another example of the plasma discharge treatment 20 as described above. The plasma discharge treatment container 20 of FIG. 1 uses the cylindrical fixed electrode 22 whereas FIG. The plasma discharge processing vessel 20 shown in FIG.
Compared with the cylindrical electrode 22 shown in FIG. 1, the prismatic electrode 29 shown in FIG. 2 has the effect of extending the discharge range (discharge area), so that the transparent conductive film of the present invention is formed. Preferably used.
[0053]
FIG. 3 is a schematic view showing an example of the above-described cylindrical roll electrode 21, FIG. 4 is a schematic view showing an example of the cylindrical fixed electrode 22, and FIG. 5 shows an example of a prismatic fixed electrode 29. FIG.
[0054]
In FIG. 3, a roll electrode 21 serving as a ground electrode is a ceramic coating obtained by thermally spraying ceramic as a dielectric coating layer on a conductive base material 21a such as metal and then sealing with an inorganic compound sealing material. It is comprised by the combination which coat | covered the process dielectric material 21b. The ceramic-coated dielectric 21b is covered with 1 mm of a single wall and grounded. As the ceramic material used for thermal spraying, alumina, silicon nitride, or the like is preferably used. Among these, alumina is more preferable because it is easily processed.
[0055]
Alternatively, the dielectric layer may be a lining treated dielectric provided with an inorganic material by lining. As the lining material, silicate glass, borate glass, phosphate glass, germanate glass, tellurite glass, aluminate glass, vanadate glass and the like are preferably used. Of these, borate glass is particularly preferred because it is easy to process.
[0056]
Examples of the conductive base material 21a such as metal include metals such as titanium, silver, platinum, stainless steel, aluminum, and iron, a composite material of iron and ceramics, or a composite material of aluminum and ceramics. Stainless steel is preferred from the viewpoint.
In the present embodiment, the base material of the roll electrode is a stainless steel jacket roll base material having a cooling means with cooling water (not shown).
[0057]
4 and 5 show a fixed electrode 22 and an electrode 29 which are application electrodes, and are configured in the same combination as the roll electrode 21 described above. That is, a hollow stainless steel pipe is covered with the same dielectric as described above, and can be cooled with cooling water during discharge.
[0058]
A power source for applying a voltage to the application electrode is not particularly limited, but a high frequency power source (200 kHz) manufactured by Pearl Industry, a high frequency power source (800 kHz) manufactured by Pearl Industry, a high frequency power source manufactured by JEOL (13.56 MHz), and a high frequency power source manufactured by Pearl Industry. A power source (150 MHz) or the like can be used.
[0059]
FIG. 6 is a conceptual diagram showing an example of the plasma discharge treatment apparatus 10 used in the present invention.
In FIG. 6, the portion of the plasma discharge treatment vessel 20 is the same as that shown in FIG. 2, but a gas generator 40, a power source 50, an electrode cooling unit 70, and the like are further arranged as the device configuration. As a coolant for the electrode cooling unit 70, an insulating material such as distilled water or oil is used.
[0060]
The electrodes 21 and 29 shown in FIG. 6 are the same as those shown in FIGS. 3, 4, 5, etc., and the gap between the opposing electrodes is set to about 1 mm, for example.
The distance between the electrodes is determined in consideration of the thickness of the solid dielectric provided on the conductive base material of the electrodes, the magnitude of the applied voltage, the purpose of using plasma, and the like. When the solid dielectric is provided on one of the electrodes, the shortest distance between the solid dielectric and the electrode, and the distance between the solid dielectrics when the solid dielectric is provided on both electrodes is uniform in any case. From the viewpoint of discharging, 0.5 mm to 20 mm is preferable, and 1 mm ± 0.5 mm is particularly preferable.
A roll electrode 21 and a fixed electrode 29 are disposed at predetermined positions in the plasma discharge processing vessel 20, and the flow rate of the mixed gas generated by the gas generator 40 is controlled and supplied from the air supply port 27 via the gas filling means 41. The plasma discharge treatment vessel 20 is filled, filled with the mixed gas used for the plasma treatment, and exhausted from the exhaust port 28. Next, a voltage is applied to the electrodes 21 and 29 by the power source 50, and the roll electrode 21 is grounded to the ground to generate discharge plasma. Here, the base material F is supplied from the roll-shaped original winding base material 60, and the electrodes in the plasma discharge treatment container 20 are in a single-sided contact state (in contact with the roll electrode 21) via the guide roller 24. The surface of the base material F is formed by discharge plasma (CVD) during transport, and then transported to the next step via the guide roller 25. Here, the base material F is formed only on the surface not in contact with the roll electrode 21.
[0061]
The value of the voltage applied to the electrode 29 fixed from the power supply 50 is determined as appropriate. For example, the voltage is about 10 V to 10 kV, and the power supply frequency is adjusted to more than 100 kHz and 150 MHz or less. As for the power supply method, either a continuous sine wave continuous oscillation mode called continuous mode or an intermittent oscillation mode called ON / OFF intermittently called pulse mode may be adopted, but the continuous mode is better. A denser and better quality film can be obtained.
[0062]
The plasma discharge treatment vessel 20 is preferably a treatment vessel made of Pyrex (R) glass or the like, but may be made of metal as long as it can be insulated from the electrodes. For example, polyimide resin or the like may be attached to the inner surface of an aluminum or stainless steel frame, and the metal frame may be subjected to ceramic spraying to obtain insulation.
When the substrate is made of resin, the temperature of the substrate during the discharge plasma treatment is set to room temperature (15 ° C. to 25 ° C.) to 200 in order to minimize the influence on the substrate during the discharge plasma treatment. It is preferable to adjust to a temperature of less than ° C, and more preferably to adjust to room temperature to 100 ° C. In order to adjust to the above temperature range, the electrode and the substrate are subjected to discharge plasma treatment while being cooled by a cooling means as necessary.
[0063]
In the present invention, the above-described discharge plasma treatment is performed at or near atmospheric pressure. Here, near atmospheric pressure represents a pressure of 20 kPa to 110 kPa, but in order to preferably obtain the effects described in the present invention. Is preferably 93 kPa to 104 kPa.
[0064]
In the discharge electrode according to the present invention, the maximum height (Rmax) of the surface roughness defined by JIS B 0601 on the side in contact with at least the substrate of the electrode may be adjusted to 10 μm or less. From the viewpoint of obtaining the effects described in the present invention, more preferably, the maximum value of the surface roughness is 8 μm or less, and particularly preferably, it is adjusted to 7 μm or less. In order to achieve this, it is preferable to polish the surface.
The centerline average surface roughness (Ra) specified by JIS B 0601 is preferably 0.5 μm or less, more preferably 0.1 μm or less.
[0065]
In addition, although the plasma discharge processing apparatus 10 shown in FIGS. 1-6 mentioned above was an apparatus used when the base material F can be bent like a film etc., the base material L with a certain amount of thickness is used. Alternatively, when it is difficult to wind a hard substrate L, such as glass or a lens, around the roll electrode, a plasma discharge processing apparatus 100 as shown in FIG. 7 is used. FIG. 7 is a schematic view showing another example of the plasma discharge treatment apparatus.
[0066]
The plasma discharge treatment apparatus 100 is generally configured by a power source 110, an electrode 120, and the like. The electrode 120 includes an upper plate electrode 121 and a lower plate electrode 122, and the upper plate electrode 121 and the lower plate electrode 122. Are arranged opposite to each other.
The upper plate electrode 121 is configured by arranging a plurality of substantially rectangular plate electrodes 121a,... Facing left and right, and gaps between the plurality of electrodes 121a,. It is said that ... That is, a gas supply unit 124 is provided above the upper plate electrode 121, and reactive gas and discharge gas are supplied from the gas supply unit 124 into the gas flow path units 123,. It is ejected between the lower plate electrode 122.
The lower flat plate electrode 122 is grounded to the ground, attaches the base material L to the surface thereof, and reciprocates the base material L in the front-rear direction with respect to the gas flow path portion 123. Therefore, when the lower flat plate electrode 122 moves, a plasma state is formed between the upper flat plate electrode 121 and the lower flat plate electrode 122, and film formation is performed on the base material L.
[0067]
Next, the gas used for forming the transparent conductive film of the present invention will be described.
In forming the transparent conductive film of the present invention, the gases used are basically a discharge gas and a reactive gas that is in a plasma state to form the transparent conductive film. They may be mixed or supplied separately.
[0068]
The reactive gas used in the present invention preferably contains a reducing gas. The reducing gas is an inorganic gas that does not contain oxygen in the molecule and has chemical reducing properties. Specific examples include hydrogen, hydrogen sulfide, and water. Particularly preferred is hydrogen gas. The amount of the reducing gas can be used in the range of 0.0001 to 5.0% by volume with respect to the mixed gas. A preferred range is 0.001 to 3.0% by volume.
[0069]
It is considered that the reducing gas acts on the reactive gas that forms the transparent conductive film and has an effect of forming a transparent conductive film having good electrical characteristics.
[0070]
The gas introduced into the plasma discharge space in the present invention preferably does not substantially contain oxygen gas. The fact that it does not substantially contain oxygen gas means that it does not hinder the action of imparting good electrical characteristics by the reducing gas as described above. In the method for forming a transparent conductive film of the present invention, the presence of oxygen gas tends to deteriorate the electrical characteristics of the transparent conductive film, and if it does not deteriorate, a slight content is allowed. In order to form an atmosphere substantially free of oxygen gas, it is preferable to use a high purity gas as the discharge gas used in the present invention.
[0071]
It is preferable to contain 0.01-10 volume% of reactive gas with respect to the whole quantity of the gas supplied to discharge space. As the film thickness of the transparent conductive film, a transparent conductive film in the range of 0.1 nm to 1000 nm is obtained.
[0072]
Examples of the discharge gas include Group 18 elements of the periodic table, specifically helium, neon, argon, krypton, xenon, radon, nitrogen, etc. In order to obtain the effects described in the present invention, Argon, helium or nitrogen is particularly preferably used.
[0073]
The reactive gas is in a plasma state in the discharge space and contains a component that forms a transparent conductive film, and an organometallic compound such as a β-diketone metal complex, a metal alkoxide, or an alkyl metal is used. The reactive gas includes a reactive gas that is a main component of the transparent conductive film and a reactive gas that is used in a small amount for the purpose of doping. Furthermore, there is a reactive gas used to adjust the resistance value of the transparent conductive film.
[0074]
The transparent conductive film of the present invention is characterized by high carrier mobility. As is well known, the electrical conductivity of the transparent conductive film is represented by the following formula (1).
[0075]
σ = neμ (1)
Here, σ is the electric conductivity, n is the carrier density, e is the quantity of electrons, and μ is the carrier mobility. In order to increase the electrical conductivity, it is necessary to improve the carrier density or carrier mobility. However, as the carrier density is increased, the reflectance increases from around 2 × 10 ²¹ cm ^{−3 and the} transparency is lost. . Therefore, it is necessary to improve carrier mobility in order to improve electric conductivity. The carrier mobility of a transparent conductive film produced by a commercially available DC magnetron sputtering method is about 30 cm ² / sec · V, but the conditions are optimized by the method for forming a transparent conductive film according to the present invention. Thus, it was found that a transparent conductive film having carrier mobility exceeding that of the transparent conductive film formed by the DC magnetron sputtering method can be formed.
[0076]
Since the method for forming a transparent conductive film according to the present invention has high carrier mobility, a low-resistance transparent conductive film having a specific resistance value of 1 × 10 ⁻³ Ω · cm or less can be obtained without doping. It is possible to further reduce the resistance by doping and increasing the carrier density. In addition, a high resistance transparent conductive film having a specific resistance of 1 × 10 ⁻² or more can be obtained by using a reactive gas that increases the resistance value as necessary.
[0077]
The transparent conductive film of the present invention has a carrier mobility of 10 cm ² / V · sec or more.
[0078]
Further, the transparent conductive film of the present invention has a carrier density of 1 × 10 ¹⁹ cm ⁻³ or more, and 1 × 10 ²⁰ cm ⁻³ or more under more preferable conditions.
[0079]
Moreover, since the transparent conductive film of this invention uses an organometallic compound as reactive gas, it may contain a trace amount of carbon. In this case, the carbon content is preferably 0 to 5.0 atom concentration. Particularly preferably, it is within the range of 0.01 to 3 atomic number concentration.
[0080]
In the present invention, the reactive gas used as the main component of the transparent conductive film is preferably an organometallic compound having an oxygen atom in the molecule. For example, indium hexafluoropentanedionate, indiummethyl (trimethyl) acetylacetate, indium acetylacetonate, indium isoporopoxide, indium trifluoropentanedionate, tris (2,2,6,6-tetramethyl 3,5 -Heptanedionate) indium, di-n-butylbis (2,4-pentanedionate) tin, di-n-butyldiacetoxytin, di-t-butyldiacetoxytin, tetraisopropoxytin, tetrabutoxytin, Examples thereof include zinc acetylacetonate. Of these, indium acetylacetonate, tris (2,2,6,6-tetramethyl 3,5-heptanedionate) indium, zinc acetylacetonate and di-n-butyldiacetoxytin are particularly preferable. .
[0081]
Examples of the reactive gas used for doping include aluminum isopropoxide, nickel acetylacetonate, manganese acetylacetonate, boron isopropoxide, n-butoxyantimony, tri-n-butylantimony, di-n-butylbis ( 2,4-pentanedionate) tin, di-n-butyldiacetoxytin, di-t-butyldiacetoxytin, tetraisopropoxytin, tetrabutoxytin, tetrabutyltin, zinc acetylacetonate, propylene hexafluoride, A cyclobutane octafluoride, methane tetrafluoride, etc. can be mentioned.
[0082]
Examples of the reactive gas used for adjusting the resistance value of the transparent conductive film include titanium triisopropoxide, tetramethoxysilane, tetraethoxysilane, and hexamethyldisiloxane.
[0083]
The amount ratio of the reactive gas used as the main component of the transparent conductive film and the reactive gas used in a small amount for the purpose of doping differs depending on the type of the transparent conductive film to be formed. For example, in the ITO film obtained by doping tin with indium oxide, the reactive gas amount is adjusted so that the In / Sn atomic ratio of the obtained ITO film is in the range of 100 / 0.1 to 100/15. To do. Preferably, it adjusts so that it may become the range of 100 / 0.5-100 / 10. The atomic ratio of In / Sn can be determined by XPS measurement.
[0084]
In a transparent conductive film (referred to as FTO film) obtained by doping fluorine with tin oxide, the reaction is performed so that the Sn / F atomic ratio of the obtained FTO film is in the range of 100 / 0.01 to 100/50. Adjust the quantity ratio of sex gases. The atomic ratio of Sn / F can be determined by XPS measurement.
[0085]
In the In ₂ O ₃ —ZnO-based amorphous transparent conductive film (IZO film), the amount ratio of the reactive gas is adjusted so that the In / Zn atomic ratio is in the range of 100/50 to 100/5. The atomic ratio of In / Zn can be determined by XPS measurement.
[0086]
Moreover, in the ITO film | membrane, FTO film | membrane, and IZO film | membrane mentioned above, it is preferable that the doping amount of Sn is 5 wt% or less, for example.
[0087]
Furthermore, as described above, the transparent conductive film of the present invention has peak intensities of hydrogen ions and metal element ions in the transparent conductive film when dynamic SIMS measurement (dynamic secondary ion mass spectrometry measurement) of the transparent conductive film is performed. It is preferable that the variation in the depth direction of the ratio H / M is not more than a certain value. The variation is preferably expressed by a coefficient of variation, and the coefficient of variation is preferably within 5%, more preferably within 3%, and even more preferably within 1%. For dynamic SIMS, practical surface analysis secondary ion mass spectrometry (2001, Maruzen) edited by the Surface Science Society may be referred to.
[0088]
The preferred dynamic SIMS measurement conditions in the present invention are as follows.
Apparatus: ADEPT 1010 or 6300 type secondary ion mass spectrometer manufactured by Physical Electronics Co. Primary ion: CS
Primary ion energy: 5.0 KeV
Primary ion current: 200 nA
Primary ion irradiation area: 600 μm square secondary ion uptake ratio: 25%
Secondary ion polarity: Negative
Secondary ion species detected: H- and M-
Mass spectrometry is performed while performing sputtering in the depth direction of the transparent conductive film under the above conditions. From the obtained depth profile, the peak intensity ratio H / M of hydrogen ions and main metal element ions is obtained. In addition, after calculating | requiring H / M ratio with respect to 100 nm, the measurement point calculates | requires the average of H / M ratio and a relative standard deviation about 15 to 85% of a depth direction, and remove | divides by averaging a relative standard deviation Multiply by 100 to obtain the coefficient of variation of the H / M ratio, that is, the variation.
[0089]
In addition, it is preferable that the absolute value of H / M ratio in this invention is between 0.001-50. More preferably, it is between 0.01-20. In this case as well, the H / M ratio is obtained based on the results of measurement under the above conditions in the depth direction using dynamic SIMS, and the average of the H / M ratio is defined as the H / M ratio for 15 to 85% in the depth direction. To do.
[0090]
Furthermore, the hydrogen concentration in the transparent conductive film in the present invention is preferably 0.001 to 10 atomic%, more preferably 0.01 to 5 atomic%, and more preferably 0.5 to 1 atomic%. The hydrogen concentration is preferably evaluated by dynamic SIMS.
The measurement conditions are as described above. Actually, first, the hydrogen concentration in the transparent transparent conductive film used as a reference is obtained by Rutherford backscattering spectroscopy, the dynamic SIMS measurement of this reference product is performed, and the relative sensitivity coefficient is determined based on the intensity of the detected hydrogen ion. Then, dynamic SIMS measurement is performed on the transparent conductive film actually used, and the hydrogen concentration in the sample is calculated using the signal intensity obtained from the measurement and the relative sensitivity coefficient obtained previously. In the present invention, the hydrogen concentration is a so-called depth profile for obtaining the hydrogen concentration over the entire thickness of the transparent conductive film, and the average of the hydrogen concentration at a depth of 15 to 85% of the transparent conductive film is defined as the hydrogen concentration.
[0091]
The method for obtaining a transparent conductive film having a variation coefficient of 5% or less in the depth direction of the peak intensity ratio H / M between hydrogen ions and main metal element ions by dynamic SIMS measurement according to the present invention is not particularly limited. Such a film forming method by atmospheric pressure plasma discharge treatment can be employed. That is, under an atmospheric pressure or a pressure near atmospheric pressure, a reactive gas is introduced into the discharge space to form a plasma state, and the substrate is exposed to the plasma state reactive gas to thereby form a transparent conductive film on the substrate. This is a method for forming a transparent conductive film. Preferably, when the reactive gas contains a reducing gas, the coefficient of variation tends to be 5% or less. More preferably, if the electric field applied to the discharge space exceeds a frequency of 100 kHz and the output density is 1 W / cm ² or more, the variation coefficient is easily set to 5% or less. Although details are unknown, it is likely that such a reducing atmosphere and high power electric field conditions are suitable for homogeneous film formation of the transparent conductive film, and thus hydrogen ions and main metal elements in the film thickness direction. It is estimated that the variation in the peak intensity of ions could be suppressed.
[0092]
Next, the base material which can be used for this invention is demonstrated.
The base material that can be used in the present invention is not particularly limited as long as it can form a transparent conductive film on the surface thereof, such as a film-like material or a three-dimensional material such as a lens shape. If the substrate can be placed between the electrodes, it can be placed between the electrodes, and if the substrate cannot be placed between the electrodes, the generated plasma can be sprayed onto the substrate to conduct transparent conduction. A film may be formed.
[0093]
The material constituting the substrate is not particularly limited, but a resin can be preferably used because it is under atmospheric pressure or a pressure near atmospheric pressure and low-temperature glow discharge.
For example, in the case of a transparent conductive film as in the present invention, the substrate is preferably a cellulose ester such as a cellulose triacetate film, polyester, polycarbonate, polystyrene, further gelatin, polyvinyl alcohol (PVA), acrylic resin on these. , Polyester resin, cellulose-based resin and the like can be used.
[0094]
Specific examples of the base material include polyester films such as polyethylene terephthalate and polyethylene naphthalate, polyethylene films, polypropylene films, cellophane, cellulose diacetate films, cellulose acetate butyrate films, cellulose acetate propionate films, and cellulose acetates. Films made of cellulose esters such as phthalate film, cellulose triacetate, cellulose nitrate or derivatives thereof, polyvinylidene chloride film, polyvinyl alcohol film, ethylene vinyl alcohol film, syndiotactic polystyrene film, polycarbonate film, norbornene resin film , Polymethylpentene film, polyetherketone Irumu, polyimide film, polyether sulfone film, polysulfone film, polyether ketone imide film, a polyamide film, a fluororesin film, a nylon film, polymethyl methacrylate film, acrylic film or polyarylate film.
[0095]
These materials can be used alone or in combination as appropriate. Among these, cellulose triacetate (TAC) is preferably used. Moreover, ZEONOR (manufactured by Nippon Zeon Co., Ltd.) and ARTON (manufactured by JSR Corporation) containing norbornene resins (amorphous cyclopolyolefin resins) known in JP-A-3-14882 and JP-A-3-122137, etc. ) And the like can be preferably used. The norbornene-based resin specifically includes a ring-opening polymer of a norbornene-based monomer, a hydrogenated product thereof, an addition-type polymer of a norbornene-based monomer, a norbornene-based monomer (the above-mentioned publication, JP-A-2-227424). No., and JP-A-2-276842) and addition polymers of olefins. The norbornene-based monomer may be polymerized by a known method. If necessary, hydrogenation of a thermoplastic norbornene-based resin, specifically, the above-described zeonore or ARTON can be obtained.
[0096]
Furthermore, even for materials having a large intrinsic birefringence such as polycarbonate, polyarylate, polysulfone and polyethersulfone (PES) (for example, Sumitrite FS-1300 manufactured by Sumitomo Bakelite Co., Ltd.), solution casting and melt extrusion It can be obtained by appropriately setting stretching conditions and the like in the longitudinal and lateral directions.
[0097]
Moreover, an organic inorganic hybrid base material can also be used for a base material. The organic / inorganic hybrid substrate is obtained by hydrolytic polycondensation of a polymer or a polymerizable monomer having a hydrogen bond accepting group and a reactive metal compound such as a metal alkoxide.
Polymers include polyvinyl alcohol, polyvinyl acetate, polyvinyl pyrrolidone, polyimide, polyamide, polycarbonate, polyurea, polyester, polyurethane, poly (2-methyl-2-oxazoline), polyacrylamide, poly (N-isopropylacrylamide), poly (Dimethylacrylamide), polyether imide, cellulose ester and the like can be mentioned, among which cellulose ester is preferable.
Polymerized polymers include isoprene, 1,3-butadiene, p-cyanostyrene, p-methoxystyrene, methacrylonitrile, p-chlorostyrene, styrene, α-methylstyrene, methyl methacrylate, methyl vinyl ketone, acrylonitrile, methyl acrylate. Vinyl acetate, ethylene, isobutene, vinylidene chloride, vinyl chloride, isobutyl ether, dimethylacrylamide and the like.
Examples of the metal alkoxide include alkoxides such as silicon, zirconium, titanium, germanium, etc. Among them, silicon and titanium alkoxides are preferable.
As a specific production method, it is possible to synthesize with reference to JP-A No. 2000-122038.
[0098]
The film thickness of these films is preferably 10 μm to 1000 μm.
[0099]
As described above, by performing atmospheric pressure plasma treatment with the plasma discharge treatment apparatus, a transparent conductive film is formed on the base material to obtain the transparent conductive base material for the organic EL display device of the present invention.
[0100]
In addition, after forming the transparent conductive film on the base material, an antireflection layer or antifouling is provided on the surface opposite to the surface on which the transparent conductive film is formed, between the base material and the transparent conductive film, or both. It is preferable to provide a layer or a hard coat layer.
A preferred configuration example of the substrate in this case is as follows.
(I) Antifouling layer / antireflection layer / base material / intermediate layer (adhesive layer) / transparent conductive film (ii) antifouling layer / antireflection layer / base material / intermediate layer (gas barrier layer) / transparent conductive film (iii ) Antifouling layer / antireflection layer / hard coat layer / base material / intermediate layer (gas barrier layer) / transparent conductive film
The hard coat layer is formed by coating the hard coat layer coating composition on the substrate with an extrusion coater so as to have a predetermined film thickness, and then drying in a drying section set at 80 ° C., and then at 120 mJ / cm ² . It is formed by irradiating with ultraviolet rays.
[0102]
The antireflection layer and the gas barrier layer can be formed by atmospheric pressure plasma processing under predetermined processing conditions using the above-described plasma discharge processing apparatus 10 shown in FIG.
[0103]
The antifouling layer is formed, for example, by adding isopropyl alcohol to a heat-crosslinkable fluorine-containing polymer to prepare a 0.2% by mass coarse dispersion and applying it to the surface of the outermost layer with a bar coater. By providing the antifouling layer, dirt and fingerprints attached to the surface can be easily wiped off.
[0104]
【Example】
EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited to these. First, the transparent conductive films of Examples 1 to 6 and Comparative Examples 1 and 2 shown below were prepared.
[Example 1 of the present invention]
(Base material)
A PET substrate (50 mm × 50 mm × 0.2 mm) is used, and the plasma discharge apparatus 100 shown in FIG. 7 is used. And the said base material was mounted in the surface of the lower type | mold flat electrode plate 122, and the transparent conductive film formation was performed on the plasma processing conditions shown below.
(Plasma power frequency and manufacturer)
13.56 MHz (high frequency power supply JRF-10000 manufactured by JEOL Ltd.)
(Discharge output condition)
7W / cm ²
(Gas condition)
Discharge gas: Helium ... 98.5% by volume
Reactive gas 1: Hydrogen ... 0.25% by volume
Reactive gas 2: Tris (2,4-pentanedionato) indium ... 1.2% by volume
Reactive gas 3: Dibutyltin diacetate ... 0.03% by volume
(electrode)
As a ground electrode, a 200 mm × 200 mm × 2 mm stainless steel plate is coated with a high-density, high-adhesion alumina sprayed coating, and then a solution obtained by diluting tetramethoxysilane with ethyl acetate is applied and dried, then cured by ultraviolet irradiation and sealed. Hole processing was performed, and the surface of the dielectric thus coated was polished, smoothed and processed to have an Rmax of 5 μm.
On the other hand, as the application electrodes, a plurality of hollow square pure titanium pipes coated with the same dielectric material as described above under the same conditions were prepared as opposing electrode groups.
Under the above reaction conditions, an atmospheric pressure plasma treatment was performed on the substrate to form an ITO film.
[0104]
[Example 2 of the present invention]
(Base material)
A PET substrate (50 mm × 50 mm × 0.2 mm) on which a silica film having a film thickness of about 50 nm is formed as a barrier coat layer.
In addition, atmospheric pressure plasma treatment was performed under the same conditions as in Example 1 to form an ITO film on the substrate.
[0105]
[Example 3 of the present invention]
(Base material)
A TAC film (50 mm × 50 mm × 0.1 mm) on which an ultraviolet curable resin layer having a film thickness of about 4 μm is formed as a hard coat layer. The hard coat layer was formed by the method described in the examples of JP-A-2001-337201.
(Discharge output condition)
6W / cm ²
Note that (plasma power supply frequency and manufacturer), (gas conditions), and (electrode) were subjected to atmospheric pressure plasma treatment under the same conditions as in Example 1 to form an ITO film on the substrate.
[0106]
[Embodiment 4 of the present invention]
(substrate)
A JSR Arton film substrate (50 mm × 50 mm × 0.2 mm) on which a silica film having a film thickness of about 50 nm is formed as a barrier coat layer.
(Plasma power frequency and manufacturer)
2 MHz (Pearl Industry Co., Ltd. high frequency power supply LP-1000-2M)
(Discharge output condition)
12W / cm ²
(Gas condition)
Discharge gas: Helium ... 98.5% by volume
Reactive gas 1: Hydrogen ... 0.25% by volume
Reactive gas 2: Tris (2,4-pentanedionato) indium ... 1.2% by volume
Reactive gas 3: bis (2,4-pentanedionato) zinc ... 0.5% volume In addition, as (electrode), the thing similar to Example 1 is used, an atmospheric pressure plasma process is performed, and a base material is used. An IZO film was formed on the top.
[0107]
[Embodiment 5 of the present invention]
(substrate)
A ZEONOR film substrate (50 mm × 50 mm × 0.2 mm) manufactured by Nippon Zeon, on which a silica film having a film thickness of about 50 nm is formed as a barrier coat layer.
(Plasma power frequency and manufacturer)
800 kHz (Pearl Industries Co., Ltd. high frequency power supply LP-1000-800K)
(Discharge output condition)
10 W / cm ²
(Gas condition)
Discharge gas: Helium ... 98.5% by volume
Reactive gas 1: Hydrogen ... 0.25% by volume
Reactive gas 2: Tris (2,4-pentanedionato) indium ... 1.2% by volume
Reactive gas 3: Dibutyltin diacetate ... 0.05% by volume
In addition, the atmospheric pressure plasma process was performed using the same thing as Example 1 as (electrode), and the ITO film | membrane was created on the base material.
[0108]
[Embodiment 6 of the present invention]
(Base material)
A glass substrate (50 mm × 50 mm × 1 mm) on which a silica film having a film thickness of about 50 nm is formed as an alkali barrier coat layer.
Note that (plasma power supply frequency and manufacturer), (discharge output condition), and (gas condition) are the same as in Example 5, and (electrode) is the same as in Example 1, and atmospheric pressure is used. Plasma treatment was performed to form an ITO film on the substrate.
[0109]
[Comparative Example 1]
A transparent conductive film was formed as follows using the method described in Example 3 of JP-A-2000-303175.
(Plasma power frequency and manufacturer)
10 kHz (PHF-4K manufactured by HEIDEN Laboratory)
(Discharge output condition)
0.8 W / cm ²
(Gas condition)
Discharge gas: Helium ... 80% by volume
Reactive gas 1: Oxygen ... 0.25% by volume
Reactive gas 2: Tris (2,4-pentanedionato) indium ... 1.2% by volume
Reactive gas 3: Dibutyltin diacetate ... 0.03% by volume
In addition, the same thing as Example 6 is used as (base material), and the atmospheric pressure plasma process is performed using the same thing as Example 1 as (electrode), and an ITO film | membrane is created on a base material. did.
[0110]
[Comparative Example 2]
Using a discharge plasma processing apparatus described in Example 1 of JP-A-2001-74906, a pulse electric field having a peak value of 10 kV, a discharge current density of 100 mA / cm ² and a frequency of 6 kHz was applied to form a film for 1 minute.
The same material as in Example 6 was used as the (base material), the same conditions as in Comparative Example 1 were used as (gas conditions), and the same materials as in Example 1 were used as (electrodes). Atmospheric pressure plasma treatment was performed to form an ITO film on the substrate.
[0111]
And the resistivity and the light transmittance were evaluated with respect to the transparent conductive film created by Examples 1 to 6 and Comparative Examples 1 and 2 of the present invention described above, and the results are shown in Table 1.
"Resistivity"
According to JIS-R-1637, it calculated | required by the four terminal method. For the measurement, Lorester GP, MCP-T600 manufactured by Mitsubishi Chemical was used.
<Light transmittance>
In accordance with JIS-R-1635, measurement using a spectrophotometer 1U-4000 type manufactured by Hitachi, Ltd. was performed. The wavelength of the test light was 550 nm.
[0112]
[Table 1]

From the results in Table 1, the transparent conductive film according to the present invention is formed at high power (high frequency voltage exceeding 100 kHz, power of 1 W / cm ² or more) under atmospheric pressure or pressure near atmospheric pressure. Compared to the case of forming with low power in Examples 1 and 2, it was confirmed that the resistance was low and the light transmittance was excellent.
[0113]
Next, transparent conductive films of Examples 7 and 8 and Comparative Example 3 shown below were prepared.
[0114]
[Embodiment 7 of the present invention]
(Discharge output condition)
5W / cm ²
(Gas condition)
Discharge gas: Helium ... 98.74% by volume
Reactive gas 1: Water ... 0.01% by volume
Reactive gas 2: Indium acetylacetonate ... 1.2% by volume
Reactive gas 3: Dibutyltin diacetate ... 0.05% by volume
The same material as in Example 6 is used as the (base material), and the atmospheric pressure plasma treatment is performed under the same conditions as in Example 1 as the (plasma power supply frequency and manufacturer) and (electrode). An ITO film was formed on the material.
[0115]
[Embodiment 8 of the present invention]
(Gas condition)
Discharge gas: helium ... 98.60 vol%
Reactive gas 1: Hydrogen ... 0.15% by volume
Reactive gas 2: Indium acetylacetonate ... 1.2% by volume
Reactive gas 3: Dibutyltin diacetate ... 0.05% by volume
In addition, as (electrode), the same thing as Example 1 is used, (Substrate), (Plasma power supply frequency and manufacturer), (Discharge output condition) are the same conditions as Example 7, and atmospheric pressure plasma The process was performed and the ITO film | membrane was created on the base material.
[0116]
[Comparative Example 3]
A transparent conductive film was formed as follows using the method described in Example 3 of JP-A-2000-303175.
(Gas condition)
Discharge gas: helium ... 98.75 volume%
Reactive gas 1: Hydrogen ... 0.5% by volume
Reactive gas 2: Indium acetylacetonate ... 1.2% by volume
Reactive gas 3: Dibutyltin diacetate ... 0.05% by volume
The (base material) is the same as in Example 7, the (plasma power supply frequency and manufacturer), the (discharge output condition) is the same as in Comparative Example 1, and the (electrode) is in Example 1. Was used, and atmospheric pressure plasma treatment was performed to form an ITO film on the substrate.
[0117]
And with respect to the transparent conductive film created by Examples 7 and 8 and Comparative Example 3 of the present invention, in the depth direction of the peak intensity ratio H / M of hydrogen ions and main metal element ions by the dynamic SIMS measurement described above. The coefficient of variation was determined and the results are shown in Table 2. The evaluation of resistivity and light transmittance is also shown in Table 2.
[0118]
[Table 2]

From the results of Table 2, the performance of the transparent conductive film is further improved by setting the coefficient of variation of the peak intensity ratio H / M of the transparent conductive film of the transparent conductive substrate for organic EL display devices of the present invention within 5%. It was recognized that
[0119]
Moreover, the simple matrix drive organic EL element was produced with the method shown below using the base material with which the transparent conductive film produced by Examples 1-8 of this invention mentioned above and Comparative Examples 1-3 was formed.
(Method for creating organic EL element)
First, the electrode was patterned. Then, it ultrasonically cleaned using neutral detergent, acetone, and ethanol, and then pulled up from boiling ethanol and dried. Next, after the surface of the transparent conductive film was UV / O ₃ cleaned, N, N′-diphenyl-m-tolyl-4,4′-diamine-1,1′-biphenyl (TPD) was deposited at a deposition rate of 0 using a vacuum deposition apparatus. The film was deposited at a thickness of 55 nm at 2 nm / sec to form a hole injection transport layer.
Furthermore, Alq3: tris (8-quinolinolato) aluminum was vapor-deposited to a thickness of 50 nm at a vapor deposition rate of 0.2 nm / sec to form an electron injection transport / light-emitting layer.
Next, a negative electrode was formed to a thickness of 200 nm using an Al · Sm alloy (Sm: 10 at%) as a target by DC sputtering with a sputtering apparatus. Ar was used as the sputtering gas at this time, the gas pressure was 3.5 Pa, and the distance between the target and the substrate (Ts) was 9.0 cm. The input power was 1.2 W / cm ² .
Finally, SiO ₂ was sputtered to a thickness of 200 nm to obtain an organic EL light emitting device as a protective layer. In this organic EL element, two parallel striped negative electrodes and eight parallel striped electrodes are orthogonal to each other, and 2 × 2 mm vertical and horizontal single elements (pixels) are arranged at intervals of 2 mm. 8 × 2 16-pixel elements.
[0120]
The organic EL device thus obtained was observed for the occurrence of dark spots.
《Dark spot number evaluation》
The number of dark spots after one week treatment was examined in an atmosphere of 60 ° C. and 95% RH. As an evaluation method, ◎ when dark spots are not observed, ◯ when less than 5 dark spots are in a 10 mm square area, and × when there are 5 or more dark spots in a 10 mm square area, and the results are shown in Table 3. Indicated.
[0121]
[Table 3]

From the results in Table 3, it was confirmed that no dark spots were generated in Examples 1 to 8 of the present invention.
[0122]
Further, when the obtained organic EL element was driven at 9 V, a luminance of 350 cd / m ² was obtained in Example 1, but in Comparative Examples 1 to 3, it was 50 cd / m ² or less. The required light emission intensity was not obtained.
[0123]
In addition, when only the base material of Example 1 was changed to the following, and an ITO film, which was a transparent conductive film, was formed on the base material under other similar conditions, Example 1 and Equivalent performance was obtained.
As the substrate, polyethersulfone (PES) (for example, Sumitrite FS-1300 manufactured by Sumitomo Bakelite Co., Ltd.), an organic-inorganic hybrid substrate is used.
[0124]
Moreover, the organic-inorganic hybrid base material was created as follows.
(Production of cellulose 1)
J. et al. Appl. Polym. Sci. , 58, 1263-1274 (1995) with reference to the synthesis method. 36.93 g of diacetylcellulose (manufactured by Daicel Chemical Industries, cellulose acetate L-50, hereinafter abbreviated as DAC) was dissolved in 258.54 g of dehydrated tetrahydrofuran (hereinafter abbreviated as THF) at 60 ° C. while heating under reflux and stirring. 3.72 g of isocyanatopropyltriethoxysilane (hereinafter abbreviated as IPTES) was dropped, and 2.85 g of a solution prepared by adjusting dibutyltin dilaurate to 10% by mass with dehydrated THF was dropped as a catalyst, and the mixture was heated and refluxed for 5 hours. While stirring. When the infrared absorption spectrum of the solution was measured after 5 hours, it was confirmed that the absorption of 2271 cm- ¹ derived from the isocyanate group of IPTES had disappeared. And reprecipitated to obtain 40.50 g of white fixed (yield 99.6%). When the obtained white fixed ²⁹ Si-NMR spectrum was measured, a single absorption was observed at −45.25 ppm. Further, when the ¹³ C-NMR spectrum was measured, absorption of amide carbonyl was observed at 163.07 ppm, and it was confirmed that the target cellulose 1 was obtained.
(Preparation of base film 1)
20.0 g of the obtained cellulose 1 was dissolved in 180 g of dehydrated THF to prepare a 10% solution of cellulose 1.
In a 30 ml beaker, add 3.65 g of a 10% solution of cellulose 1, 0.41 g of tetraethoxysilane (hereinafter abbreviated as TEOS) and 0.14 g of 0.25% dilute hydrochloric acid, and stir at room temperature for 8 minutes. Then, it was spread over a petri dish made of fluororesin having a diameter of 7.5 cm, lightly covered and left at room temperature for 2 days. Two days later, when the solvent was almost volatilized, it was dried with a vacuum pump for 30 minutes to obtain a colorless and transparent base film 1. The thickness after drying was 100 μm.
[0125]
【The invention's effect】
According to the transparent conductive substrate for an organic EL display device of the present invention, low resistance, excellent light transmittance and surface smoothness, sufficient light emission intensity can be obtained, and dark spots are generated. Hateful.
[Brief description of the drawings]
FIG. 1 is a schematic view showing an example of a plasma discharge treatment vessel installed in a plasma discharge treatment apparatus used for forming a transparent conductive film of the present invention.
FIG. 2 is a schematic view showing another example of a plasma discharge treatment container.
FIG. 3 is a perspective view showing an example of a cylindrical roll electrode.
FIG. 4 is a perspective view showing an example of a fixed cylindrical electrode.
FIG. 5 is a perspective view showing an example of a fixed prismatic electrode.
FIG. 6 is a schematic view showing an example of a plasma discharge treatment apparatus.
FIG. 7 is a schematic view showing another example of a plasma discharge treatment apparatus.
FIG. 8 is a conceptual diagram illustrating a configuration example of an organic EL element.
[Explanation of symbols]
F film (base material)
L lens (base material)
10, 100 Plasma discharge treatment apparatus 21, 22 Electrode (roll electrode)
29 electrodes (fixed electrodes)
50, 110 Power supply 120 Electrode 121 Upper plate electrode 122 Lower plate electrode

Claims (8)

A method for producing a transparent conductive substrate for an organic EL display device in which a transparent conductive film is formed on a substrate,
Under atmospheric pressure or a pressure of 20 kPa to 110 kPa, a discharge gas and a reactive gas are introduced, and a high frequency voltage exceeding 100 kHz is applied between electrodes arranged to face each other so as to form a discharge space, and 1 W / cm. ^The transparent conductive film containing either ITO or IZO by bringing the reactive gas into a plasma state by supplying and discharging ^two or more electric powers, and exposing the substrate to the reactive gas in the plasma state Form the
The method for producing a transparent conductive substrate for an organic EL display device , wherein the reactive gas contains a reducing gas . In the manufacturing method of the transparent conductive base material for organic EL display devices of Claim 1 ,
A method for producing a transparent conductive substrate for an organic EL display device, wherein at least one intermediate layer is interposed between the substrate and the transparent conductive film. In the manufacturing method of the transparent conductive base material for organic electroluminescent display devices of Claim 2 ,
The said intermediate | middle layer contains an inorganic oxide, The manufacturing method of the transparent conductive base material for organic electroluminescent display apparatuses characterized by the above-mentioned. In the manufacturing method of the transparent conductive base material for organic EL display devices of any one of Claims 1-3 ,
A method for producing a transparent conductive substrate for an organic EL display device, wherein a gas barrier layer is formed on a surface of the transparent conductive film. In the manufacturing method of the transparent electroconductive base material for organic EL display devices of any one of Claims 1-4 ,
The method for producing a transparent conductive substrate for an organic EL display device, wherein the substrate is glass. In the manufacturing method of the transparent conductive base material for organic EL display devices of any one of Claims 1-5 ,
The method for producing a transparent conductive substrate for an organic EL display device, wherein the substrate is a plastic film. In the manufacturing method of the transparent conductive base material for organic EL display devices of Claim 6 ,
The said plastic film contains a polyester resin, The manufacturing method of the transparent conductive base material for organic electroluminescent display apparatuses characterized by the above-mentioned. In the manufacturing method of the transparent conductive base material for organic electroluminescent display devices of any one of Claims 1-7 ,
The transparent conductive film for an organic EL display device has a variation coefficient within 5% in the depth direction of the peak intensity ratio H / M of hydrogen ions and main metal element ions measured by dynamic SIMS. For producing a conductive substrate.

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