JP4168675B2 - Transparent conductive substrate for plasma display panel and method for producing transparent conductive substrate for plasma display panel - 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、光透過率に優れ、また、主表面内の抵抗変動が小さいことが確認された。
【０１０１】
次に、以下に示す実施例５、６、比較例３の透明導電膜を作成した。
【０１０２】
［本発明の実施例５］
（基材）
アルカリバリアコート層として膜厚約５０ｎｍのシリカ膜が形成されたガラス基板（５０ｍｍ×５０ｍｍ×１ｍｍ）。
（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、（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。
【０１０３】
［本発明の実施例６］
（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、（基材）、（電極）、（プラズマ電源周波数とメーカー）、（放電出力条件）としては、実施例５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。
【０１０４】
［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５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。
【０１０５】
そして、これら本発明の実施例５、６、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。
【０１０６】
【表２】

表２の結果より、本発明のプラズマディスプレイパネル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。
【０１０７】
また、上述した本発明の実施例１〜６、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、特開２０００−１１２４００号に記載の以下に示す方法でプラズマディスプレイパネル表示装置を作成した。
（プラズマディスプレイパネル表示装置の作成方法）
前面ガラス基板２０１上に、透明導電膜が形成済の透明導電性基材を、図８に示すように、例えば、フォトレジスト法によってパターニングして、透明導電膜の電極２０５を形成する。そして、電極２０５上に金属バス電極２０６を形成し、ＰＤＰ用電極を得る。次に、ＰＤＰ用電極を、例えば、低融点誘電体フリット（酸化ケイ素と酸化鉛を主成分とする６００℃以下で軟化する誘電体フリット）等の誘電体層２０８で覆う。次に、誘電体層２０８の表面に、例えば酸化マグネシウムで保護膜２０９を形成して、ＰＤＰ用前面基板を得る。
一方、背面ガラス基板２０２には、アドレス電極２０７と隔壁２０３とを形成し、さらに蛍光体２１０を塗布してＰＤＰ用背面基板を得る。
最後に、前面ガラス基板２０１及び背面ガラス基板２０２を組み立て、封着、排気し、最後にプラズマ放電させるためのガスを封入してＰＤＰ表示装置を完成する。
この表示装置によれば、前面ガラス基板２０１及び背面ガラス基板２０２に形成された隔壁２０３によりセル（空間）２０４が区画形成され、セル２０４中でプラズマ放電を発生させることにより、セル内壁の蛍光体層２１０が発光し画像を形成する。
【０１０８】
このようにして作成したＰＤＰ表示装置において、輝度ムラを目視評価したところ、実施例１〜６はほとんど輝度ムラはみとめられなかった。これに対し、比較例１〜３は輝度ムラが顕著であった。
【０１０９】
【発明の効果】
本発明のプラズマディスプレイパネル用透明導電性基材によれば、低抵抗でかつ、光透過性に優れ、また、プラズマディスプレイパネル表示装置を形成したときに良好に表示できる。
【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】プラズマディスプレイパネルを説明するためのもので、プラズマディスプレイパネル表示装置の断面図である。
【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 has a transparent conductive film formed on the surface, in particular, a transparent conductive substrate for a plasma display panel used for a plasma display panel, andMethod for producing transparent conductive substrate for plasma display panelIt is about.
[0002]
[Prior art]
In recent years, a plasma display panel (PDP), which is a kind of gas discharge display panel, has attracted attention as a large thin flat color display device. Various transparent conductive films have been developed as display electrodes in the plasma display panel. The transparent conductive film is desired to have a low resistance, and as the transparent conductive film used for the electrode for PDP, indium oxide (ITO) containing tin oxide is excellent in transparency, conductivity, and patterning property, and is often used. ing. This transparent conductive film is formed on a substrate such as glass.
[0003]
However, since the display portion of the PDP display device has a large area, the glass substrate also has a large area and is expensive.
Moreover, the transparent conductive film formed on a glass substrate is formed into a film by sputtering method, for example. Since this sputtering method is a vacuum film forming technique, a low-resistance transparent conductive film can be obtained. However, as the glass substrate becomes larger, the apparatus becomes very large and expensive, and a lot of time is required for evacuation. The demerit is that it is not possible to increase productivity. In addition, the target is expensive, and further, there is a problem that the use efficiency is low because replacement is necessary after using several tens of percent.
[0004]
Therefore, in order to overcome the disadvantage that the transparent conductive film for PDP made by sputtering is low productivity and high cost, discharge under atmospheric pressure or pressure near atmospheric pressure, plasma excitation of reactive gas, Methods for forming a transparent conductive film on a substrate (atmospheric pressure plasma method) are described in, for example, Japanese Patent Application Laid-Open Nos. 2000-303175 and 2001-74906. The atmospheric pressure plasma methods disclosed in these publications generate 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. That's it.
[0005]
[Problems to be solved by the invention]
  By the way, the atmospheric pressure plasma method forms a transparent conductive film under atmospheric pressure, so that it is excellent in productivity and inexpensive, and a large area transparent conductive film can be obtained. It has been insufficient as a plasma display panel application requiring light transmittance.
  The present invention has been made in view of the above circumstances, has a low resistance, is excellent in light transmittance, and can be displayed well when a plasma display panel display device is formed. andMethod for producing transparent conductive substrate for plasma display panelIt is an issue to provide.
[0015]
[Means for Solving the Problems]
  In order to solve the above problems, the invention of claim 1 is a transparent conductive substrate for a plasma display panel in which a transparent conductive film is formed on a substrate,
  The transparent conductive film isA metal oxide-based transparent conductive film containing tin containing indium as a main metal component, and under a pressure of atmospheric pressure or near atmospheric pressure, a reactive gas is introduced into a discharge space to form a plasma state, and the base material is the plasma Formed on the substrate by exposure to a reactive gas in a state, the reactive gas contains a reducing gas selected from hydrogen, hydrogen sulfide and water,
further,The transparent conductive film includes hydrogen ions by dynamic SIMS measurement.indiumThe variation in the depth direction of the peak intensity ratio H / M of the element ions is within 5% of the coefficient of variation.
[0016]
Here, H is the peak intensity of hydrogen ions, and M is the peak intensity of main metal element ions.
[0019]
  Claim2The invention of claim1In the transparent conductive substrate for plasma display panel described in
  The electric field applied to the discharge space exceeds the frequency of 100 kHz, and the output density is 1 W / cm.²It is the above.
  Invention of Claim 3 is a manufacturing method of the transparent conductive base material for plasma display panels in which the transparent conductive film was formed on the base material,
Under atmospheric pressure or near atmospheric pressure, a reactive gas is introduced into the discharge space to form a plasma state, and the substrate is exposed to the reactive gas in the plasma state, so that indium is a main metal on the substrate. Forming a metal oxide transparent conductive film containing tin as a component;
The reactive gas contains a reducing gas selected from hydrogen, hydrogen sulfide and water;
Further, the transparent conductive film is characterized in that the variation in the depth direction of the peak intensity ratio H / M of hydrogen ions and indium element ions by dynamic SIMS measurement is within 5%.
DETAILED DESCRIPTION OF THE INVENTION
  Embodiments of the present invention will be described below.
  The transparent conductive substrate for a plasma display panel according to the present invention is formed by forming a transparent conductive film on a substrate, and the transparent conductive film is interposed between opposing electrodes under atmospheric pressure or a pressure near atmospheric pressure. High frequency voltage exceeding 100 kHz and 1 W / cm²By supplying and discharging the above electric power (power density), the reactive gas is excited to be in a plasma state, and the substrate is exposed to the reactive gas in the plasma state.
[0020]
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 plasma display panels and the like. When the transparent conductive film is used for a plasma display panel as in the present invention, the thickness of the transparent conductive film is preferably about 100 to 130 nm.
[0021]
As the transparent conductive film, SnO₂, In₂O_Three, CdO, ZnO₂, SnO₂: Sb, SnO₂: F, ZnO: AL, In₂O_Three: There are a metal oxide film such as Sn and a complex oxide film by a dopant.
Examples of the complex oxide film using the dopant include an ITO film obtained by doping tin with indium oxide, an FTO film obtained by doping fluorine with tin oxide, and In₂O_ThreeExamples thereof include an IZO film made of -ZnO-based amorphous.
[0022]
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. 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.
A material having a lattice constant close to that of the base material and the transparent conductive film is preferably used for the intermediate layer. When the base material is glass, a silica layer is preferably used as the intermediate layer. Note that when non-alkali glass is used as the base material, the above-described diffusion of the alkali metal is unlikely to occur, so that the intermediate layer may not be provided.
[0023]
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. In addition, 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.²The upper limit is preferably 50 W / cm.²Or less, more preferably 20 W / cm²It is as follows. The discharge area (/ cm²) Refers to the area of the area 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.
[0024]
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.
[0025]
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.
[0026]
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.
[0027]
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 present 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-described discharge method.
In the present invention, plasma discharge is applied to a highly durable electrode capable of maintaining a uniform discharge state even when such a high-power electric field is applied to a large-area electrode under atmospheric pressure or a pressure near atmospheric pressure. It is necessary to employ in the processing equipment.
[0028]
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.
[0029]
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.
[0030]
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. Examples of such a dielectric include alumina, nitriding 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.
[0031]
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 a sealing treatment.
[0032]
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. In this case, the dielectric is made of two or more layers having different amounts of bubbles mixed in to enhance durability. 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.
[0033]
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.
[0034]
In another preferred specification of the dielectric-coated electrode according to the present invention, the difference in linear thermal expansion coefficient between the dielectric and the conductive base material is 10 × 10.^-6It is a combination that becomes / ° C or less. Preferably 8 × 10^-6/ ° C. or less, more preferably 5 × 10^-6/ ° C. or less, more 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) The conductive base material is pure titanium and the dielectric is a ceramic spray coating.
(2) The conductive base material is pure titanium and the dielectric is glass lining.
(3) The conductive base material is a titanium alloy and the dielectric is a ceramic spray coating.
(4) The conductive base material is titanium alloy and the dielectric is glass lining.
(5) The conductive base material is stainless steel and the dielectric is a ceramic spray coating.
(6) The conductive base material is stainless steel, and the dielectric is glass lining.
(7) The conductive base material is a composite material of ceramics and iron, and the dielectric is a ceramic spray coating.
(8) The conductive base material is a composite material of ceramics and iron, and the dielectric is glass lining.
(9) The conductive base material is a composite material of ceramics and aluminum, and 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. From the viewpoint of the difference in linear thermal expansion coefficient, the above (1) to (4) and (7) to (10) are preferable.
[0035]
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.
[0036]
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.
[0037]
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.
[0038]
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.
[0039]
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.
[0040]
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.
[0041]
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.
[0042]
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 the 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.
[0043]
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.
[0044]
FIG. 2 is a schematic view showing another example of the plasma discharge processing container 20 as described above, and the plasma discharge processing 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.
[0045]
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.
[0046]
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.
[0047]
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.
[0048]
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).
[0049]
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.
[0050]
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.
[0051]
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 part of the plasma discharge processing vessel 20 is the same as that shown in FIG. As a coolant for the electrode cooling unit 70, an insulating material such as distilled water or oil is used.
[0052]
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.
[0053]
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 method of applying power, 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. A denser and better quality film can be obtained.
[0054]
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.
[0055]
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.
[0056]
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.
[0057]
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 parallel plate type plasma discharge processing apparatus 100 as shown in FIG. 7 is used. In addition, even if it is a base material which can be bent, the parallel plate type plasma discharge processing apparatus 100 can be used. FIG. 7 is a schematic view showing an example of a parallel plate type plasma discharge treatment apparatus.
[0058]
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. In this way, the substrate L can be moved to form a film on the substrate L having a larger area than the discharge area.
[0059]
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.
[0060]
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.
[0061]
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.
[0062]
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.
[0063]
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.
[0064]
The discharge gas is a group 18 element of the periodic table, specifically helium, neon.
, Argon, krypton, xenon, radon, nitrogen and the like. Argon, helium or nitrogen is particularly preferably used in order to obtain the effects described in the present invention.
[0065]
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.
[0066]
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).
[0067]
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 electric conductivity, it is necessary to improve the carrier density or the carrier mobility, but if the carrier density is increased, 2 × 10^{twenty one}cm^-3Transparency is lost because the reflectance increases from the vicinity. Therefore, it is necessary to improve carrier mobility in order to improve electric conductivity. The carrier mobility of a transparent conductive film prepared by a commercially available DC magnetron sputtering method is 30 cm.²/ Sec · V, the transparent conductive film having carrier mobility exceeding the transparent conductive film formed by the DC magnetron sputtering method by optimizing the conditions according to the method for forming a transparent conductive film according to the present invention Was found to be possible to form.
[0068]
Since the method for forming a transparent conductive film according to the present invention has high carrier mobility, a specific resistance value of 1 × 10 6 is obtained even without doping.^-3A transparent conductive film having a low resistance of Ω · cm or less can be obtained. It is possible to further reduce the resistance by doping and increasing the carrier density. Further, by using a reactive gas that increases the resistance value as necessary, the specific resistance is 1 × 10^-2The above high-resistance transparent conductive film can also be obtained.
[0069]
The transparent conductive film of the present invention has a carrier mobility of 10 cm.²/ V · sec or more.
[0070]
The transparent conductive film of the present invention has a carrier density of 1 × 10¹⁹cm^-3As described above, under more preferable conditions, 1 × 10²⁰cm^-3That's it.
[0071]
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.
[0072]
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. .
[0073]
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.
[0074]
Examples of the reactive gas used for adjusting the resistance value of the transparent conductive film include titanium triisopropoxide, tetramethoxysilane, tetraethoxysilane, and hexamethyldisiloxane.
[0075]
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.
[0076]
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.
[0077]
In₂O_ThreeIn the —ZnO-based amorphous transparent conductive film (IZO film), the reactive gas quantity ratio 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.
[0078]
Further, as described above, the transparent conductive film of the present invention has a peak intensity ratio H / M of hydrogen ions and metal element ions in the transparent conductive film when dynamic secondary ion mass spectrometry measurement of the transparent conductive film is performed. It is preferable that the variation in the depth direction 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%. Regarding dynamic secondary ion mass spectrometry (hereinafter referred to as dynamic SIMS including the apparatus), practical surface analysis secondary ion mass spectrometry (2001, Maruzen) edited by the Surface Science Society may be referred to.
[0079]
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
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 relative standard deviation about 15 to 85% of the depth direction, and averaged and divided | segmented the relative standard deviation. Multiply by 100 to obtain the coefficient of variation of the H / M ratio, that is, the variation.
[0080]
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 result 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.
[0081]
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.
[0082]
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, the electric field applied to the discharge space exceeds the frequency of 100 kHz, and the output density is 1 W / cm.²If it is above, it will be easy to make the said coefficient of variation into 5% or less similarly. 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.
[0083]
Next, the base material which can be used for this invention is demonstrated.
As a base material used for a plasma display panel display device, a large-area substrate is preferable, and in particular, a main surface having a transparent conductivity is 0.1 m.²When it has the above area, it can be suitably used for a plasma display panel display device.
The substrate 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 flat plate, a film, a three-dimensional shape such as a lens. Absent. 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.
As a substrate used for the plasma display panel of the present invention, for example, glass is suitable. As the glass, high strain point glass, alkali-free glass or soda lime glass can be used. In particular, a high strain point glass is preferable, and this is disclosed in JP-A-3-40933, JP-A-7-257937, JP-A-8-165138, and the like.
[0084]
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, and further gelatin, polyvinyl alcohol (PVA), acrylic resin on these. , Polyester resin, cellulose-based resin and the like can be used.
[0085]
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.
[0086]
These materials can be used alone or in combination as appropriate. Among these, cellulose triacetate (TAC) can be preferably used. Further, ZEONOR (manufactured by ZEON CORPORATION) and ARTON (manufactured by JSR Corporation) containing a norbornene resin (amorphous cyclopolyolefin resin) known in JP-A-3-14882 and JP-A-3-122137, etc. ) And the like can be preferably used. Specifically, the norbornene resin includes a ring-opening polymer of a norbornene monomer, a hydrogenated product thereof, an addition type polymer of a norbornene monomer, a norbornene 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-mentioned zeonore or ARTON can be obtained.
[0087]
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, melt extrusion, etc. The polyether sulfone can be suitably used by appropriately setting the stretching conditions in the longitudinal and lateral directions.
[0088]
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 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.
[0089]
In addition, in the material of the resin film, from the viewpoint of heat resistance, thermosetting silicone resin, thermosetting epoxy resin, PES, polyarylate resin, polyimide resin, polyesterimide resin, heat resistant norbornene resin, organic-inorganic hybrid A material can be preferably used.
[0090]
The film thickness of these base materials is preferably 0.3 to 3.0 mm.
[0091]
As described above, by performing atmospheric pressure plasma treatment with the plasma discharge treatment apparatus, a transparent conductive film is formed on the surface of the substrate, and the transparent conductive substrate for a plasma display panel of the present invention is obtained.
[0092]
In addition, after forming the transparent conductive film on the substrate surface, after forming the transparent conductive film, after forming the electrode for the plasma display panel by patterning the transparent conductive film with, for example, a photoresist or the like, A transparent dielectric layer is preferably formed so as to cover it. As the transparent dielectric layer, for example, a low melting point dielectric frit (a dielectric frit containing silicon oxide and lead oxide as main components and softened at 600 ° C. or lower) may be used. By providing this transparent dielectric layer, when a plasma display panel display device to be described later is formed, insulation between the electrodes is secured, and the electrodes are eroded by the plasma in order to stably generate plasma. Can be prevented.
Further, when a protective layer is further formed on the transparent dielectric layer, it is possible to more suitably prevent the electrode from being eroded by plasma.
[0093]
【Example】
EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited to these. First, transparent conductive films of Examples 1 to 4 and Comparative Examples 1 and 2 shown below were prepared.
[Example 1 of the present invention]
(Base material)
Main surface area is 0.6m²Asahi Glass Co., Ltd. high strain point glass PD200 (60 cm × 100 cm × 2.1 mm) is used, and parallel plate type plasma discharge apparatus 100 shown in FIG. 7 is used. And the said base material was mounted in the surface of the lower flat electrode plate 122, and the ITO film | membrane which is a transparent conductive film was formed 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)
8W / cm²
(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
(electrode)
As a ground electrode, a 75 cm × 130 cm × 5 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. The surface of the dielectric material thus coated was polished, smoothed and processed so as 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.
[0094]
[Example 2 of the present invention]
(Discharge output condition)
12W / cm²
In addition, atmospheric pressure plasma treatment was performed under the same conditions as in Example 1 to form an ITO film on the substrate.
[0095]
[Example 3 of the present invention]
(Plasma power frequency and manufacturer)
2 MHz (Pearl Industry Co., Ltd. high frequency power supply LP-1000-2M)
(Discharge output condition)
10W / cm²
In addition, atmospheric pressure plasma treatment was performed under the same conditions as in Example 1 to form an ITO film on the substrate.
[0096]
[Embodiment 4 of the present invention]
(Plasma power frequency and manufacturer)
800KHz (High frequency power supply LP-1000-800K manufactured by Pearl Industry Co., Ltd.)
(Discharge output condition)
12W / cm²
In addition, atmospheric pressure plasma treatment was performed under the same conditions as in Example 1 to form an ITO film on the substrate.
[0097]
[Comparative Example 1]
An ITO film, which is a transparent conductive film, was formed as follows using the method disclosed in Japanese Patent Application Laid-Open No. 2000-303175.
(Base material)
Main surface area is 0.6m²High strain point glass PD200 (60 cm × 100 cm × 2.1 mm) manufactured by Asahi Glass Co., Ltd. is used.
(Plasma power frequency and manufacturer)
10KHz (PHF-4K manufactured by HEIDEN Laboratory)
(Discharge output condition)
0.8W / cm²
(Gas condition)
Discharge gas: Helium ... 98.5% 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 ... 0.05% by volume
In addition, as (electrode), the thing similar to Example 1 was used.
[0098]
[Comparative Example 2]
Using the discharge plasma processing apparatus described in Example 1 of Japanese Patent Laid-Open No. 2001-74906, the crest value is 10 kV and the discharge current density is 100 mA / cm.²A pulse electric field having a frequency of 6 kHz was applied to form a film for 1 minute.
The (base material) and (gas conditions) were subjected to atmospheric pressure plasma treatment under the same conditions as in Comparative Example 1 and (electrodes) the same as those in Example 1, and applied on the base material. An ITO film was created.
[0099]
And, for the transparent conductive film prepared by Examples 1 to 4 of the present invention described above and Comparative Examples 1 and 2, the measurement of the resistivity, light transmittance and sheet resistance fluctuation in the main surface of the transparent conductive film, 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.
《Resistance fluctuation in main surface》
By the same method as the measurement of the resistivity, the sheet resistance variation on the main surface of the transparent conductive film was measured at 50 locations to obtain CV%, and the CV% value was shown as follows.
A: Less than 3%
▲: 3% to less than 5%
×: 5% or more
[0100]
[Table 1]

From the results shown in Table 1, the transparent conductive film according to the present invention has a high power (high frequency voltage exceeding 100 kHz, 1 W / cm under atmospheric pressure or pressure near atmospheric pressure.²Compared to the case of forming with low power of Comparative Examples 1 and 2, it is confirmed that the resistance is low, the light transmittance is excellent, and the resistance fluctuation in the main surface is small. It was done.
[0101]
Next, transparent conductive films of Examples 5 and 6 and Comparative Example 3 shown below were prepared.
[0102]
[Embodiment 5 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.
(Discharge output condition)
5W / cm²
(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
Note that (plasma power supply frequency and manufacturer) and (electrode) were subjected to atmospheric pressure plasma treatment under the same conditions as in Example 1 to create an ITO film on the substrate.
[0103]
[Embodiment 6 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 (base material), (electrode), (plasma power supply frequency and manufacturer), and (discharge output condition), atmospheric pressure plasma treatment is performed under the same conditions as in Example 5 to create an ITO film on the base material. did.
[0104]
[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 vol%
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 5, 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.
[0105]
And with respect to the transparent conductive film created by Examples 5 and 6 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.
[0106]
[Table 2]

From the results in Table 2, the performance of the transparent conductive film is further improved by setting the coefficient of variation within 5% of the peak intensity ratio H / M of the transparent conductive film of the transparent conductive substrate for the plasma display panel of the present invention. Was recognized.
[0107]
Further, using the substrate on which the transparent conductive film prepared according to Examples 1 to 6 and Comparative Examples 1 to 3 of the present invention described above was formed, a plasma display was formed by the method described below in JP-A No. 2000-112400. A panel display device was created.
(Method of creating a plasma display panel display device)
On the front glass substrate 201, as shown in FIG. 8, the transparent conductive base material on which the transparent conductive film has been formed is patterned by, for example, a photoresist method to form the electrode 205 of the transparent conductive film. Then, a metal bus electrode 206 is formed on the electrode 205 to obtain a PDP electrode. Next, the electrode for PDP is covered with a dielectric layer 208 such as a low melting point dielectric frit (a dielectric frit mainly composed of silicon oxide and lead oxide and softened at 600 ° C. or lower). Next, a protective film 209 is formed on the surface of the dielectric layer 208 by using, for example, magnesium oxide to obtain a PDP front substrate.
On the other hand, the address electrodes 207 and the barrier ribs 203 are formed on the rear glass substrate 202, and the phosphor 210 is further applied to obtain a rear substrate for PDP.
Finally, the front glass substrate 201 and the rear glass substrate 202 are assembled, sealed, evacuated, and finally filled with a gas for plasma discharge to complete a PDP display device.
According to this display device, the cells (spaces) 204 are partitioned and formed by the partition walls 203 formed on the front glass substrate 201 and the rear glass substrate 202, and plasma discharge is generated in the cells 204, whereby the phosphor on the inner wall of the cell. Layer 210 emits light and forms an image.
[0108]
In the PDP display device thus created, when the luminance unevenness was visually evaluated, almost no luminance unevenness was found in Examples 1 to 6. On the other hand, the luminance unevenness was remarkable in Comparative Examples 1 to 3.
[0109]
【The invention's effect】
According to the transparent conductive substrate for a plasma display panel of the present invention, low resistance and excellent light transmittance can be displayed well when a plasma display panel display device is formed.
[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 cross-sectional view of a plasma display panel display device for explaining the plasma display panel.
[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 electrodes
121 Upper plate electrode
122 Lower plate electrode

Claims (3)

A transparent conductive substrate for a plasma display panel in which a transparent conductive film is formed on a substrate,
The transparent conductive film is a metal oxide-based transparent conductive film containing tin containing indium as a main metal component, and is brought into a plasma state by introducing a reactive gas into the discharge space under atmospheric pressure or a pressure near atmospheric pressure, It is formed on the substrate by exposing the substrate to the reactive gas in the plasma state, and the reactive gas contains a reducing gas selected from hydrogen, hydrogen sulfide and water,
Further, the transparent conductive film has a variation coefficient in a depth direction of a peak intensity ratio H / M of hydrogen ions and indium element ions measured by dynamic SIMS within a variation coefficient of 5% or less. Base material. The transparent conductive substrate for a plasma display panel according to claim 1 ,
A transparent conductive substrate for a plasma display panel, wherein an electric field applied to the discharge space exceeds a frequency of 100 kHz and an output density is 1 W / cm ² or more. A method for producing a transparent conductive substrate for a plasma display panel in which a transparent conductive film is formed on a substrate,
Under atmospheric pressure or near atmospheric pressure, a reactive gas is introduced into the discharge space to form a plasma state, and the substrate is exposed to the reactive gas in the plasma state, so that indium is a main metal on the substrate. Forming a metal oxide transparent conductive film containing tin as a component;
The reactive gas contains a reducing gas selected from hydrogen, hydrogen sulfide and water;
Further, the transparent conductive film has a variation coefficient in a depth direction of a peak intensity ratio H / M of hydrogen ions and indium element ions measured by dynamic SIMS within a variation coefficient of 5% or less. For producing a conductive substrate .

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