TW201938372A - Transparent oxide-laminated film, method for producing transparent oxide-laminated film, and transparent resin substrate - Google Patents

Abstract

Provided are: a transparent oxide-laminated film having excellent transparency, good moisture barrier performance, and chemical resistance; a method for producing the transparent oxide-laminated film; and a transparent resin substrate using the transparent oxide-laminated film. The transparent oxide-laminated film is obtained by laminating a plurality of layers of a transparent oxide film containing Zn and Sn, wherein each of the layers is composed of an amorphous transparent oxide film having a different atomic ratio of Zn to Sn. The method for producing the transparent oxide-laminated film uses sputtering targets made of different Sn-Zn-O-based oxide sintered bodies, wherein a first target having an oxide sintered body having an atomic ratio Sn/(Zn+Sn) of 0.18-0.29, and a second target having an oxide sintered body having an atomic ratio Sn/(Zn+Sn) of 0.44-0.90 are used to form the transparent oxide laminated-film.

Description

Transparent oxide laminated film, manufacturing method of transparent oxide laminated film, and transparent resin substrate

The present invention relates to a transparent oxide laminated film, a method for manufacturing a transparent oxide laminated film, and a transparent resin substrate. Specifically, the present invention relates to an amorphous transparent oxide laminated film having excellent water vapor barrier properties and chemical resistance, a method for manufacturing the same, and a transparent resin substrate forming the transparent oxide laminated film. This case claims priority based on Japanese Patent Application No. "Japanese Patent Application No. 2018-050675" filed in Japan on March 19, 2018, and its contents are incorporated in this case by referring to this application.

Water vapor barrier resin substrates covered with metal oxide films such as silicon oxide or aluminum oxide on the surface of transparent resin substrates such as plastic substrates or film substrates. Packaging for the purpose of preventing the intrusion of water vapor and preventing deterioration of foods or medicines. use. In recent years, it has also been applied to liquid crystal display elements, solar cells, electroluminescence display elements (EL elements), quantum dot (QD) display elements, quantum dot sheets (QD sheets), and the like.

For water vapor barrier transparent resin substrates used in electronic devices, especially display elements, in recent years, in accordance with the development of display elements, in addition to the requirements for weight reduction and large size, it also has performance such as flexibility in shape and flexibility in curved display. be asked for. Therefore, the glass substrates used so far have become difficult to cope with, and transparent resin substrates have been used.

However, a transparent resin substrate has a lower water vapor barrier property than a glass substrate. Therefore, there is a problem that water vapor permeates the substrate and deteriorates an electroluminescence display element, a QD display element, and the like. In addition, there are also cases in which the water vapor barrier layer is damaged by damage to the water vapor barrier layer and the barrier function due to the erosion of the chemical solution used in the formation of the base material and the bonding material of the adhesive layer and the patterning of the transparent conductive layer. The problem that the substrate deteriorates the EL display element and the QD display element. In order to improve such a problem, development of a transparent resin substrate in which a metal oxide film is formed on a resin substrate is being developed.

For example, Patent Document 1 describes a water vapor barrier transparent resin substrate in which a transparent conductive film such as a tin oxide system is formed on a transparent film by a sputtering method. According to Patent Document 1, the gist of a water vapor transmission rate of less than 0.01 g / m ² / day according to the Mocon method is described.

In addition, Patent Document 2 proposes a barrier film using a laminate of an inorganic film and an organic film. Patent Document 2 describes that the water vapor transmission rate at this time is 0.01 g / m ² / day or less, the thickness of the inorganic film is 30 nm to 1 μm, and the thickness of the organic layer is 10 nm to 2 μm.
[Prior technical literature]
[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2005-103768
[Patent Document 2] Japanese Patent No. 5161470

[Problems to be Solved by the Invention]

In recent years, with the practical use of EL display elements or QD display elements, in displays such as organic EL displays, if water vapor is mixed into the organic EL display elements, damage caused by moisture at the interface between the cathode layer and the organic layer is greatly increased. This may cause peeling between the organic layer and the cathode, or black spots in the non-luminous portion, which may cause a significant decrease in performance. The water vapor transmission rate (WVTR) required for the water vapor barrier transparent resin substrate that can be used for these displays is said to be 0.01 g / m ² / day or less, and preferably 0.005 g / m ² / day or less.

In addition, these displays also have requirements for flexibility and the like, and there is a lot of demand for thinning a water vapor barrier transparent resin substrate. The thickness of the barrier film is required to be 100 nm or less. Further, there are also strong demands for chemical resistance. Chemical resistance In order to protect the metal oxide layer from chemicals such as acids, alkalis, and organic solvents, it is reviewed to provide a chemical resistant layer made of an organic compound on the metal oxide layer.

For example, the chemical resistance of the alkaline aqueous solution or the acidic aqueous solution used in the etching step when the transparent electrode of the barrier film with a transparent electrode is patterned. Generally speaking, the transparent electrode etching step is a process of photoresist covering, photoresist exposure, photoresist development, transparent electrode etching, and photoresist peeling. The photoresist developing step and photoresist peeling step use alkaline aqueous solution in The electrode etching step uses an acidic aqueous solution. In addition, when the substrate is formed, the adhesive or sealing material of the adhesive layer also contains a solvent containing acidity and basicity. Therefore, if a part of the water vapor barrier transparent layer is eroded, the water vapor barrier property is impaired, and therefore, chemical resistance is emphasized. Elements formed with liquid crystal elements, organic EL elements, TFT elements, semiconductor elements, solar cells, etc. have weak resistance to water and oxygen, and these chemical liquids cause water vapor barrier transparent layers to be etched. Black spots or bright spots occur, and semiconductor devices and solar cells cannot function. In order to improve this problem, it is required to develop a transparent resin substrate in which a metal oxide film is formed on a resin substrate.

On the other hand, in Patent Document 1, the water vapor transmission rate is measured by the Mocon method, but it is difficult to accurately measure the Mocon method to 0.01 g / m ² / day or less. The water vapor barrier properties of actual films Still in doubt. In addition, the thin film used was 200 μm, the thickness of the barrier film was 100 to 200 nm, and the flexibility was poor.

In addition, Patent Document 2 proposes a barrier film using a laminate of an inorganic film and an organic film. However, the procedures for forming a film on an inorganic film and an organic film are different. Therefore, it is necessary to mold according to a separate program, and productivity should be deteriorated or Foreign matter may cause deterioration of characteristics. In addition, in order to achieve a water vapor transmission rate of 0.01 g / m ² / day or less, the structure is laminated to three or more layers, and the organic layer must be described at about 500 nm, which has poor flexibility.

That is, as a barrier film used for an EL display element, a QD display element, or the like, a film formed by a sputtering method is used, and further, it is required to have a thin film thickness, good water vapor transmission barrier performance, and high chemical resistance.

The present invention was made in view of such needs, and aims to provide a transparent oxide laminated film having excellent transparency, good water vapor barrier properties, and chemical resistance, a method for manufacturing the same, and using the other transparent Resin substrate.

[Means for solving problems]

The inventors of the present case conducted an intensive analysis on the composition of the above-mentioned multilayer film composed of a plurality of amorphous transparent oxide films having different metal atomic ratios of zinc and tin, which are suitable for water vapor barrier properties and chemical resistance. As a result, the present invention has been completed.

That is, in one aspect of the present invention, a transparent oxide layered film in which a plurality of layers of transparent oxide films containing zinc and tin are laminated is formed by amorphous transparent oxidation with different metal atomic ratios of zinc and tin in each layer. Material film.

According to one aspect of the present invention, by changing the metal atomic ratio of zinc to tin in each layer, a layer having water vapor barrier properties and a layer having chemical resistance can be formed to have good water vapor barrier properties. Laminated film with chemical-resistant transparent oxide.

At this time, in one aspect of the present invention, the first transparent oxide film may have at least a metal atomic ratio Sn / (Zn + Sn) of 0.18 to 0.29, and a metal atomic ratio Sn / (Zn + Sn ) Is a second transparent oxide film of 0.44 to 0.90.

When Sn / (Zn + Sn) is 0.18 or more and 0.29 or less, water vapor barrier properties are excellent, and when Sn / (Zn + Sn) is 0.44 or more and 0.90 or less, it becomes a transparent oxide film having excellent chemical resistance.

In addition, in one aspect of the present invention, at least any one of the transparent oxide films may include tantalum and germanium, and the atomic ratio of zinc, tin, tantalum, and germanium Ta / (Zn + Sn + Ge + Ta) is 0.01. Hereinafter, Ge / (Zn + Sn + Ge + Ta) is 0.04 or less.

Tantalum and germanium are components derived from the target, whereby the film formation speed is improved by improving the conductivity of the target itself, and the film can be formed stably by increasing the target density.

In addition, in one aspect of the present invention, the film thickness of the transparent oxide laminate film may be 100 nm or less.

By setting the film thickness to 100 nm or less, a transparent oxide laminated film having excellent flexibility can also be obtained.

In addition, in one aspect of the present invention, the water vapor transmission rate of the transparent oxide laminated film may be 0.001 g / m ² / day or less according to the differential pressure method specified by the K7129 method of the Japanese Industrial Standard JIS standard.

By satisfying the foregoing requirements, it can be said that it is a transparent oxide laminated film having excellent water vapor barrier properties.

In addition, in one aspect of the present invention, it may be a transparent oxide laminated film, which has chemical resistance to acids or alkalis, and is immersed in 5% strength hydrochloric acid or 5% strength sodium hydroxide solution for 5 minutes The color difference change value ΔEab is 1.0 or less.

By satisfying the aforementioned requirements, it can be said that it is a transparent oxide laminated film having excellent chemical resistance.

In addition, in one aspect of the present invention, it may be a transparent oxide laminated film, which has chemical resistance to acids or alkalis, and is immersed in 5% strength hydrochloric acid or 5% strength sodium hydroxide solution for 5 minutes before or after immersion. The amount of film change was 2.0 nm or less.

By satisfying the aforementioned requirements, it can be said that it is a transparent oxide laminated film having excellent chemical resistance.

Another aspect of the present invention is a method for manufacturing a transparent oxide laminated film that is sputtered using a target composed of a Sn-Zn-O oxide sintered body, using at least a metal atomic ratio Sn / (Zn + Sn ) Is a first target of an oxide sintered body of 0.18 or more and 0.29 or less, and a second target of an oxide sintered body having a metal atomic ratio Sn / (Zn + Sn) of 0.44 or more and 0.90 or less to form a transparent oxide laminate. membrane.

According to another aspect of the present invention, a transparent oxide film having excellent water vapor barrier properties can be formed by sputtering using the first target, and a transparent oxide having excellent chemical resistance can be formed by sputtering using the second target.物 膜。 The film.

Another aspect of the present invention is a transparent resin substrate in which the aforementioned transparent oxide laminate film is formed on at least one side of a transparent resin substrate.

According to another aspect of the present invention, by forming the transparent oxide laminate film described above, a transparent resin substrate having both excellent water vapor barrier properties and chemical resistance can be obtained.

At this time, in another aspect of the present invention, the transparent oxide film having a metal atomic ratio Sn / (Zn + Sn) of 0.44 to 0.90 may be the outermost layer.

Since such a transparent oxide film has chemical resistance, it is preferably formed on the outermost layer of a transparent resin substrate.

[Effect of the invention]

According to the present invention, it is possible to provide a transparent oxide laminate film having excellent transparency, good water vapor barrier performance, and chemical resistance by direct current sputtering with high mass productivity.

Hereinafter, the transparent oxide laminated film, the manufacturing method of a transparent oxide laminated film, and a transparent resin substrate concerning this invention are demonstrated in the following order. The present invention is not limited to the following examples, and can be arbitrarily changed within a range not departing from the gist of the present invention.
Transparent oxide laminated film
2. Manufacturing method of transparent oxide laminated film
3. Transparent resin substrate

＜ 1. Transparent oxide laminated film ＞
According to one aspect of the present invention, a transparent oxide laminated film comprising a plurality of layers of transparent oxide films containing zinc and tin is laminated by an amorphous transparent oxide film having different metal atomic ratios of zinc and tin in each layer. Make up. In this way, by changing the metal atomic ratio of zinc to tin in each layer, a layer having water vapor barrier properties and a layer having chemical resistance can be formed into a transparent layer having good water vapor barrier properties and chemical resistance. Oxide laminated film.

The amorphous transparent oxide laminated film (hereinafter also referred to as oxide laminated film) of the present invention is mainly used as a water vapor barrier film. Plastic substrates or thin-film substrates, such as liquid crystal display elements or flexible display elements such as solar cells and electroluminescence (EL) display elements, are covered with a sputtering method as a metal oxide film, and are used in water vapor The purpose of blocking, etc. to prevent deterioration.

When the oxide laminated film is a crystalline film, crystal grain boundaries exist in the film, and water vapor penetrates through the crystal grain boundaries, and thus the performance of the water vapor barrier is reduced. In addition, in the aforementioned Patent Document 1, a tin oxide film is proposed as this amorphous film, and when a tin oxide film is formed by a sputtering method, a target material for a sputtering target used for sputtering is formed. The same composition of tin oxide. This tin oxide-based target generally has high acid resistance but a low relative density of the target, and there are many problems such as the inability to form a stable film due to target cracking during sputtering. In the transparent oxide layered film according to the present invention, the aforementioned doubts are resolved by using a later-described Sn-Zn-O-based sputtering target.

That is, an oxide sputtered laminated film related to one embodiment of the present invention is characterized by being an amorphous transparent oxide film containing zinc and tin, and laminated with transparent metals having different metal atomic ratios of zinc and tin. Made of oxide film. The number of laminated transparent oxide films is not particularly limited as long as it is at least two layers. In addition, for the two transparent oxide films having different metal atomic ratios of zinc and tin, the first transparent oxide film having a metal atomic ratio Sn / (Zn + Sn) of 0.18 or more and 0.29 or less is compared with the metal atomic ratio Sn. The second transparent oxide film having a ratio of (/ Zn + Sn) of 0.44 to 0.90 is preferred.

The first transparent oxide film has good water vapor barrier performance (low water vapor transmission rate) when the metal atomic ratio Sn / (Zn + Sn) is 0.18 or more and 0.29 or less.

When the metal atomic ratio Sn / (Zn + Sn) is less than 0.18, since the ratio of SnO ₂ decreases, the precipitation of highly crystalline ZnO increases, the amount of crystallized portions (microcrystalline state) in the film increases, and water Vapor flows in from the crystal grain boundary, and an oxide sputtering film having desired water vapor barrier properties cannot be obtained.

On the other hand, when the aforementioned metal atomic ratio Sn / (Zn + Sn) is larger than 0.29, the SnO ₂ ratio becomes larger, so the stress of the film becomes stronger, and further, heat generation during film formation becomes larger, and the film is generated. It is impossible to obtain an oxide sputter film having a water vapor barrier property which can be used for OLED, QD, etc. due to peeling or damage to the substrate.

In addition, the second transparent oxide film has good chemical resistance when the metal atomic ratio Sn / (Zn + Sn) is 0.44 or more and 0.90 or less.

Zinc oxide (ZnO) is easy to dissolve in medicines such as acid / base, and has the disadvantage of lacking resistance to medicines such as acid / base. For example, a high-definition patterning process based on wet etching is difficult. However, tin oxide (SnO ₂ ) has extremely high chemical resistance. Here, the second transparent oxide film containing zinc and tin is made of SnO ₂ as the main component, so that chemical resistance such as acid and alkali can be obtained.

In the case where the metal atomic ratio Sn / (Zn + Sn) is smaller than 0.44, the ZnO ratio becomes large and the chemical resistance is inferior.

On the other hand, when the metal atomic ratio Sn / (Zn + Sn) is greater than 0.90, the density of the sintered body of the target used during sputtering is low, and the possibility of cracking defects of the sintered body during sputtering is high. .

The first transparent oxide film and the second transparent oxide film are made of the same type of oxide. Therefore, a sputtering method widely used in industry can be used for film formation. The sputtering method is effective because it has high mass productivity and can form a uniform film thickness. In addition, when a sputtering device having a plurality of targets is provided depending on the sputtering device, a target (a first target and a second target described later) used for the first oxide film and the second oxide film is provided, and sputtering is performed simultaneously. Plating is possible, and productivity is excellent. In addition, since the first oxide film and the second oxide film are both amorphous oxide films containing zinc and tin, the film has high adhesion during lamination, and the film formation can be eased because the film is amorphous. Film stress generated when

At least one of the first transparent oxide film and the second transparent oxide film further contains tantalum and germanium, and the metal atomic ratio Ta / (Zn + Sn + Ge + Ta) of the tantalum to zinc, tin, and germanium is 0.01 Hereinafter, the metal atomic ratio Ge / (Zn + Sn + Ge + Ta) of the germanium to zinc, tin, and tantalum is preferably 0.04 or less.

Contains tantalum or germanium and also has a crystallization temperature of 600 ° C or higher, so that an amorphous film structure is easily obtained. In addition, the crystallization temperature is high, so even when there is a thermal influence during the mass production process, the amorphous state can be easily maintained. In addition, the addition of tantalum and germanium at the aforementioned ratio has the effect of further improving the characteristics of a sputtering target containing zinc and tin.

Hereinafter, the added elements (Ta, Ge) will be briefly described. The sputtering target is an oxide sintered body composed of only Sn-Zn, and a backing plate made of copper, stainless steel, or the like is used to connect and fix the material. Get together (join).

An oxide sintered body composed of only a Sn—Zn composition may have insufficient conductivity and a large specific resistance. In sputtering, the larger the specific resistance value is, the larger the energy needs to be used for sputtering, and the film-forming speed cannot be increased. Therefore, it is necessary to increase the electrical conductivity of the sintered body used for the target. In the oxide sintered body, Zn ₂ SnO ₄ , ZnO, and SnO ₂ are poor in conductivity. Therefore, even if the compound ratio or the amount of ZnO and SnO ₂ is adjusted by adjusting the blending ratio, the conductivity cannot be significantly improved.

It is preferable to add tantalum (Ta) here. Tantalum can displace Zn in ZnO phase, Zn in Zn ₂ SnO ₄ phase or Sn in Sn, SnO ₂ phase, and solid solution, so it does not form ZnO phase and spinel with wurtzite crystal structure. Compound phases other than the Zn ₂ SnO ₄ phase with a crystal structure and the SnO ₂ phase with a rutile crystal structure. The addition of tantalum can maintain the density of the oxide sintered body while improving the conductivity.

In addition, the sintered density of the oxide sintered body composed only of the Sn—Zn composition is about 90%, which cannot be said to be sufficient. If the density of the oxide sintered body is low, there is a problem such that the film cannot be formed stably due to cracking of the oxide sintered body or the like during sputtering.

It is preferable to add a specific amount of germanium (Ge) here. In the oxide sintered body, germanium can dissolve Zn in the ZnO phase, Zn in the Zn ₂ SnO ₄ phase, or Sn in the Sn, SnO ₂ phase and solid solution, so it does not form a wurtzite type crystal structure. Compound phases other than the ZnO phase, the Zn ₂ SnO ₄ phase with a spinel crystal structure, and the SnO ₂ phase with a rutile crystal structure. The addition of germanium has the effect of densifying the oxide sintered body. Thereby, the sintered density of the oxide sintered body can be made higher.

That is, the oxide sintered body further contains tantalum and germanium, the metal atomic ratio Ta / (Zn + Sn + Ge + Ta) of the tantalum and zinc, tin, and germanium is 0.01 or less, and the germanium and zinc, tin, and The metal atomic ratio of tantalum is preferably 0.04 or less Ge / (Zn + Sn + Ge + Ta). In addition, the addition of tantalum and germanium can obtain the approximate lower limit of the aforementioned effect, and the aforementioned metal atomic ratios of tantalum and germanium are both 0.0005.

When the number of metal atoms of tantalum, zinc, tin, and germanium is greater than Ta / (Zn + Sn + Ge + Ta) greater than 0.01, other compound phases such as compound phases such as Ta ₂ O ₅ and ZnTa ₂ O ₆ may be generated. , So the conductivity cannot be greatly improved. In addition, when the number of metal atoms of germanium, zinc, tin, and tantalum is greater than Ge / (Zn + Sn + Ge + Ta) than 0.04, other compound phases, such as Zn ₂ Ge ₃ O ₈ and other compound phases, Therefore, the density of the oxide sintered body becomes low, and the target becomes easily broken during sputtering.

Sputtering using a target with added tantalum and germanium will not affect the formed oxide sputtered film. For example, the influence of water vapor transmission rate was not recognized. The same applies to chemical resistance. Therefore, tantalum is contained at a ratio of Ta / (Zn + Sn + Ge + Ta) of 0.01 or less, and germanium is contained at a ratio of Ge / (Zn + Sn + Ge + Ta) of 0.04 or less, without deteriorating the performance of the water vapor barrier. An amorphous oxide sputtered film with good characteristics was obtained. The same applies to chemical resistance.

The film thickness of the oxide laminate film is preferably 100 nm or less, and more preferably 90 nm or less. By setting the film thickness as such, an oxide laminated film having excellent flexibility can be provided.

The thickness of the transparent oxide laminated film in which the first oxide film and the second oxide film are combined may be 100 nm or less, and preferably 90 nm or less. Therefore, the respective thicknesses of the first oxide film and the second oxide film are not limited.

In one aspect of the present invention, the water vapor transmission rate of the differential pressure method specified by the K7129 method of the Japanese Industrial Standard JIS standard for the oxide laminated film is preferably 0.001 g / m ² / day or less. As mentioned above, the water vapor transmission rate (WVTR) required for a water vapor barrier transparent resin substrate that can be used for a display is said to be 0.01 g / m ² / day or less, preferably 0.005 g / m ² / day or less . The water vapor transmission rate of the oxide laminated film of the present invention is 0.001 g / m ² / day or less, and it can be sufficiently used for these applications.

The water vapor transmission rate is mainly affected by the first oxide film, and is particularly affected by the film thickness. The water vapor transmission rate becomes smaller as the film thickness becomes thicker. Therefore, considering the necessary water vapor transmission rate, each film thickness is appropriately set.

In one aspect of the present invention, the second oxide film has chemical resistance. The evaluation of chemical resistance was performed with a color difference ΔEab. The color difference was evaluated using the L * a * b * color system (CIE1976). The so-called L * a * b * is a color system, where L * is lightness, a * and b * are hue and chroma, and chromaticity indicates that L * is a value from 0 to 100, the larger the closer to white. a * is the axis from red to green, + a is the red direction, -a is the green direction, b * is the yellow to blue axis, + b is the yellow direction, -b is the blue direction, and a * b * are all 0 The occasion is achromatic. The color difference ΔEab is calculated by the color difference calculation formula of CIE1976. Assay for assessing L before and after *, a *, b *, and the difference before and after as ΔL *, Δa *, Δb * , a color difference ΔEab to ^{((ΔL *) 2 + (} Δa *) 2 + (Δb *) 2 ) ^1/2 Find it.

In one aspect of the present invention, chemical resistance is confirmed for chemical resistance to acids and bases. A solution with hydrochloric acid resistance at 5% concentration and alkali resistance resistance at 5% concentration of sodium hydroxide were immersed for 5 minutes, respectively, and the color difference ΔEab before and after the change can be evaluated. If this color difference ΔEab is large, the color tone will change before and after the treatment, and it is estimated that the oxide layer film is discolored due to the drug. When the value of the change in color difference ΔEab is 1.0 or less, and preferably 0.5 or less, it can be judged that the drug layer causes little dissolution of the oxide laminate film and has chemical resistance.

In addition, in one aspect of the present invention, chemical resistance can also be confirmed by a change in the thickness of the film after acid or alkali impregnation. The thickness changes before and after immersion in the drug, and the dissolved amount of zinc and tin was confirmed by the ICP-AES method for the drug in the impregnated sample. The film thickness reduction (film change) can be calculated from the results, the film formation area, and the film density. Chemical resistance is judged if the film thickness reduction amount (film change amount) after immersion for 5 minutes in a solution of hydrochloric acid having an acid resistance of 5% and sodium hydroxide having an alkali resistance of 5% has a value of 2.0 nm or less.

As described above, tin oxide (SnO ₂ ) has extremely high chemical resistance. By setting the amorphous second transparent oxide film containing zinc and tin to SnO ₂ as the main component and Sn / (Zn + Sn) to be 0.44 or more and 0.90 or less, the color difference ΔEab can be changed to 0.5 or less. It is also possible to set the film change amount to 2.0 nm or less.

From the above, according to the transparent oxide laminate film according to one embodiment of the present invention, it can have excellent transparency, good water vapor barrier properties, and chemical resistance.

<2. Manufacturing method of transparent oxide laminated film>
Next, a method for manufacturing a transparent oxide laminate film according to an embodiment of the present invention will be described. One aspect of the present invention is a method for manufacturing a transparent oxide laminated film that is sputtered using a target composed of a Sn-Zn-O-based oxide sintered body, using at least a metal atomic ratio Sn / (Zn + Sn ) Is a first target of an oxide sintered body of 0.18 or more and 0.29 or less, and a second target of an oxide sintered body having a metal atomic ratio Sn / (Zn + Sn) of 0.44 or more and 0.90 or less to form a transparent oxide laminate. membrane.

As described above, in the method for manufacturing a transparent oxide multilayer film according to an embodiment of the present invention, a Sn-Zn-O-based oxide sintered body is used for sputtering to obtain 2 having different metal atomic ratios between zinc and tin. An amorphous laminated film. That is, a transparent oxide film having excellent water vapor barrier properties can be formed by sputtering using the first target, and a transparent oxide film having excellent chemical resistance can be formed by sputtering using the second target.

Preparing a first target having a sintered body having a zinc / tin metal atomic ratio Sn / (Zn + Sn) of 0.18 or more and 0.29 or less contained in the aforementioned oxide sintered body at the time of sputtering of the first oxide film, And a target formed by using a second target of a sintered body having a Sn / (Zn + Sn) ratio of zinc to tin contained in the oxide sintered body of 0.4 to 0.90 during sputtering of the second oxide film . The technical significance of the composition range of each sintered body is as described above.

In addition, the total thickness of the sputtered oxide laminate film is preferably 100 nm or less, and more preferably 90 nm or less. As described above, by doing so, it is possible to provide an oxide laminate film having good water vapor barrier properties and more excellent flexibility. The respective thicknesses of the first oxide film and the second oxide film are not particularly limited.

The sputtering may be performed by using a sputtering target composed of the aforementioned oxide sintered body. The sputtering apparatus is not particularly limited, and a DC magnetron sputtering apparatus or the like can be used.

For the sputtering conditions, the degree of vacuum in the vacuum chamber is adjusted to 1 × 10 ^-4 Pa or less. The atmosphere in the vacuum chamber is an inert gas. The inert gas is argon or the like, and its purity is preferably 99.999% by mass or more. In addition, the inert gas contains 4 to 10 volume percent oxygen for the total gas flow rate. The oxygen concentration affects the surface resistance value of the film, so the oxygen concentration has been set in such a manner as to have a specific resistance value. After that, a specific DC power supply was used, and it was placed between the sputtering target and the substrate to generate a plasma based on the DC pulse, followed by sputtering to form a film. The film thickness is controlled by the film formation time.

After sputtering, a second oxide film is formed after the first oxide film is formed. In this case, when a plurality of targets are provided in the sputtering device, a first target used for the first oxide film and a second target used for the second oxide film can be provided, and continuous sputtering can be performed by using the same device. Continuous formation can improve productivity. In addition, it is a target of the same kind, and the film has good adhesion and affinity.

From the above, according to the method for manufacturing a transparent oxide laminated film related to one embodiment of the present invention, with high-volume DC sputtering, excellent transparency and good water vapor barrier performance can be obtained. Chemical resistant oxide laminated film.

<3. Transparent resin substrate>
A transparent resin substrate according to an embodiment of the present invention is one in which at least two amorphous transparent oxide laminated films having different zinc-tin metal atomic ratios are formed on a transparent substrate. The transparent oxide laminate film is formed on at least one side of the substrate. The first oxide film has a zinc / tin metal atomic ratio Sn / (Zn + Sn) of 0.18 or more and 0.29 or less. The second oxide film preferably has a metal atomic ratio Sn / (Zn + Sn) of zinc to tin of 0.44 or more and 0.90 or less. The thickness of the transparent oxide laminate film is preferably 100 nm or less, and more preferably 90 nm or less.

Transparent substrates can be polyethylene terephthalate, polyethylene, naphthalate, polycarbonate, polyfluorene, polyetherfluorene, polyarylate (PAR), cycloolefin polymer, fluorine Resin, polypropylene, polyimide resin, epoxy resin, etc. In addition, the thickness of the transparent resin substrate is not particularly limited, and it is preferably 50 to 150 μm in view of flexibility, cost, and device requirements.

The sputtering method to the transparent substrate may be performed by sputtering as described in the manufacturing method of the transparent oxide layered film. The technical significance of the appropriate metal atomic ratio or film thickness of zinc and tin is as described above.

In addition, in a transparent resin substrate according to an embodiment of the present invention, an amorphous transparent oxide vapor barrier film containing zinc and tin may be formed on at least one side of the substrate, but It can also be laminated through other films. For example, a silicon oxide film, a silicon nitride oxide film, a resin film, a wet coating film, a metal film, an oxide film, and the like are formed on the aforementioned substrate, and then the foregoing oxide is sputtered as a water vapor barrier layer It may be formed on at least one side.

In one aspect of the present invention, it is preferable that the second oxide film be the outermost layer. That is, it is preferable that the second oxide film having chemical resistance is formed on the outer side (surface side) of the first oxide film. In detail, in the subsequent steps, a second oxide film is formed on the outermost surface of the surface side using an acid or alkaline chemical in the step of preparing a transparent electrode or the step of applying an adhesive. The first oxide film mainly has water vapor barrier properties. When this surface is formed on the surface side, the chemical resistance is weak, and there is a high possibility that the characteristics of the water vapor barrier are also impaired due to the drug. By forming the second oxide film of the present invention on the outer side (surface side) of the first oxide film, it is possible to maintain both of chemical resistance and water vapor barrier characteristics.

A transparent resin substrate according to an embodiment of the present invention can be used to form, for example, a flexible OLED display element, a flexible QD display element, or a QD sheet.

From the above, according to the transparent resin substrate related to one embodiment of the present invention, with high-volume direct current sputtering, it can have excellent transparency, good water vapor barrier performance, and chemical resistance.

[Example]

Hereinafter, examples of the present invention will be specifically described with reference to comparative examples. However, the technical scope of the present invention is not limited to the content described in the following examples, and it goes without saying that the scope of the present invention can be modified and implemented.

In the following examples, SnO ₂ powder and ZnO powder were used. In addition, when an additive element is added, Ta ₂ O ₅ powder is used as the tantalum element, and GeO ₂ powder is used as the elemental germanium.

(Example 1)
In Example 1, a sintered body was produced with zinc oxide as the main component and tin oxide having a metal atomic ratio Sn / (Zn + Sn) of 0.26, and tin oxide having a metal atomic ratio Sn / (Zn + Sn) is a sintered body manufactured in a manner of 0.49, a sputtering target (manufactured by Sumitomo Metal Mining Co., Ltd.) is produced, and a sputtering device is used to form a film by using a sputtering device. This sputtering device used a DC magnetron sputtering device (type SH-550 manufactured by ULVAC).

Film formation of an amorphous oxide sputtering film was performed under the following conditions. A target is mounted on the cathode, and a resin film substrate is disposed directly above the cathode. The distance between the target and the resin film substrate was 80 mm. The resin film substrate on which film formation is performed is caused to stand still on the opposite side of the cathode, and the film formation is performed in a stationary opposite direction. As the resin film substrate, a PEN film (manufactured by Teijin, thickness 50 μm) was used. When the vacuum degree in the vacuum chamber reached 2 × 10 ^-4 Pa or less, argon gas having a purity of 99.9999% by mass was introduced into the vacuum chamber so that the pressure was 0.6 Pa. Among argon gas containing 5% oxygen, DC was used as a direct current power source. The power supply device (manufactured by Delta Electronics, MDX) puts 1500W of DC power using a 20kHz DC pulse into the sputtering target-PEN thin film substrate made by Teijin to generate a plasma based on the DC pulse in the PEN film made by Teijin A first oxide film was formed on the substrate by sputtering to have a film thickness of 50 nm so that tin oxide had a metal atomic ratio Sn / (Zn + Sn) of 0.26. Next, a second oxide film having a metal atomic ratio Sn / (Zn + Sn) of 0.49 was formed at a film thickness of 50 nm by sputtering.

The crystallinity, water vapor transmission rate (WVTR), and chemical resistance of the formed oxide sputtered film were confirmed. The crystallinity was measured by X-ray diffraction, and diffraction peaks were observed. The water vapor transmission rate was measured by a differential pressure method (DELTAPERM-UH manufactured by Technolox). The transmittance is the average transmittance of visible light with a wavelength of 550 nm measured with a spectrophotometer. The evaluation method of chemical resistance is to immerse the sample in 5% hydrochloric acid or 5% sodium hydroxide aqueous solution for 5 minutes. The temperature of the medicine at this time is normal temperature. The samples before and after the immersion of the drug were measured using a spectrophotometer (Konica Minolta Co., Ltd. type: CM-5) to calculate the color difference ΔEab. In addition, the amount of film thickness reduction (film change) before and after immersion of the drug, the chemical solution of the impregnated sample was confirmed by the ICP-AES method (ICPS-8100 manufactured by Shimadzu Corporation), and the results and film formation Area and film density to calculate the amount of film change. For the evaluation of chemical resistance, a transparent oxide laminate film was formed on a glass substrate so that the substrate did not dissolve. The results are shown in Table 1.

(Example 2)
In Example 2, the method was performed such that the metal atomic ratio Sn / (Zn + Sn) of the first oxide film was 0.18 and the metal atomic ratio Sn / (Zn + Sn) of the second oxide film was 0.59. Except for sputtering, it carried out similarly to Example 1, and obtained the transparent oxide laminated film, and measured it. The results are shown in Table 1.

(Example 3)
In Example 3, a first oxide film was formed with a film thickness of 70 nm by sputtering, and then a second oxide film having a metal atomic ratio Sn / (Zn + Sn) of 0.68 was formed by sputtering with a film thickness of 20 nm. Other than that, it carried out similarly to Example 1, and obtained the transparent oxide laminated film, and measured it. The results are shown in Table 1.

(Example 4)
In Example 4, a transparent oxide layer was obtained in the same manner as in Example 1 except that a first oxide film was formed with a film thickness of 15 nm by sputtering and then a second oxide film was formed with a film thickness of 15 nm by sputtering. The film was deposited and measured. The results are shown in Table 1.

(Example 5)
In Example 5, a first oxide film having a metal atomic ratio Sn / (Zn + Sn) of 0.22 was formed at a film thickness of 15 nm by sputtering, and a metal atomic ratio Sn was formed at a film thickness of 15 nm by sputtering. Except for the second oxide film having a (Zn + Sn) of 0.59, the same procedure as in Example 1 was carried out to obtain a transparent oxide layered film, and the measurement was performed. The results are shown in Table 1.

(Example 6)
In Example 6, the first oxide film was formed with a film thickness of 20 nm by sputtering, and the second oxide film with a metal atomic ratio Sn / (Zn + Sn) of 0.68 was then formed by sputtering with a film thickness of 10 nm. Other than that, it carried out similarly to Example 1, and obtained the transparent oxide laminated film, and measured it. The results are shown in Table 1.

(Example 7)
In Example 7, the metal atomic ratio Sn / (Zn + Sn) was 0.22, and Ta / (Zn + Sn + Ge + Ta) was 0.01, and Ge / (Zn + Sn + A first oxide film having a Ge + Ta) of 0.04 was formed in the same manner as in Example 1 except that the second oxide film was formed to a thickness of 20 nm by sputtering. A transparent oxide laminate film was obtained and measured. The results are shown in Table 1.

(Example 8)
In Example 8, a first oxide film having a metal atomic ratio Sn / (Zn + Sn) of 0.18 was formed at a film thickness of 85 nm by sputtering, and a metal atomic ratio Sn was formed at a film thickness of 15 nm by sputtering. Except for the second oxide film whose / (Zn + Sn) is 0.79, Ta / (Zn + Sn + Ge + Ta) is 0.01, and Ge / (Zn + Sn + Ge + Ta) is 0.04, the same operation as in Example 1 is performed. A transparent oxide laminate film was obtained and measured. The results are shown in Table 1.

(Example 9)
In Example 9, the metal atomic ratio Sn / (Zn + Sn) was 0.28, Ta / (Zn + Sn + Ge + Ta) was 0.01, and Ge / (Zn + Sn + Ge + Ta) was formed by sputtering. The first oxide film of 0.04 was formed by sputtering to have a metal atomic ratio Sn / (Zn + Sn) of 0.68, Ta / (Zn + Sn + Ge + Ta) of 0.01, and Ge / (Zn + Sn + Ge Except for the second oxide film having + Ta) of 0.04, it was carried out in the same manner as in Example 1 to obtain a transparent oxide laminate film, and the measurement was performed. The results are shown in Table 1.

(Comparative example 1)
In Comparative Example 1, the first oxide film having a metal atomic ratio Sn / (Zn + Sn) of 0.18 was formed by sputtering, and the metal atomic ratio Sn / (Zn + Sn) was 0.29 by sputtering. Except for the second oxide film, it was carried out in the same manner as in Example 1 to obtain a transparent oxide laminate film, and the measurement was performed. The results are shown in Table 1.

(Comparative example 2)
In Comparative Example 2, the first oxide film having a metal atomic ratio Sn / (Zn + Sn) of 0.16 was formed by sputtering, and the metal atomic ratio Sn / (Zn + Sn) was formed by sputtering of 0.49. Except for the second oxide film, it was carried out in the same manner as in Example 1 to obtain a transparent oxide laminate film, and the measurement was performed. The results are shown in Table 1.

(Comparative example 3)
In Comparative Example 3, except that a first oxide film having a metal atomic ratio Sn / (Zn + Sn) of 0.35 was formed at a film thickness of 15 nm by sputtering, and a metal atomic ratio Sn was formed at a film thickness of 15 nm by sputtering. Except for the second oxide film whose / (Zn + Sn) is 0.79, Ta / (Zn + Sn + Ge + Ta) is 0.01, and Ge / (Zn + Sn + Ge + Ta) is 0.04, the same operation as in Example 1 is performed. A transparent oxide laminate film was obtained and measured. The results are shown in Table 1.

As can be seen from Table 1, in Examples 1 to 9 included in the present invention, the water vapor transmission rate of the differential pressure method specified by the K7129 method of the Japanese Industrial Standard JIS is 0.001 g / m ² / day or less (1.0 × 10 ^-3 g / m ² / day or less), with good water vapor barrier performance. Furthermore, the color difference ΔEab of the evaluation of chemical resistance was 1.0 or less, and the amount of film change was 2.0 nm or less, and it was found that it has good chemical resistance.

On the other hand, in Comparative Example 1 in which the Sn / (Zn + Sn) of the second oxide film was 0.29, in the evaluation of chemical resistance, the transparent oxide laminate film was dissolved in acid or alkali.

In addition, Comparative Example 2 in which Sn / (Zn + Sn) of the first oxide film is 0.16, or Comparative Example 3 in which Sn / (Zn + Sn) of the first oxide film is 0.35, in accordance with Japanese Industrial Standard JIS specifications K7129 method specified water vapor transmission rate of the differential pressure, over ^{0.001g / m 2 /day(1.0×10 -3 g /} m 2 / day), found inferior in water vapor barrier. In addition, the transmittance measured at a wavelength of 550 nm was also 90% or more, and it was found to have transparency. As a result of crystallinity measurement by X-ray diffraction, all of Examples 1 to 9 were amorphous.

As described above, according to the present invention, it is possible to obtain a transparent oxide laminate film having excellent transparency, good water vapor barrier performance, and chemical resistance by direct current sputtering with high mass productivity.

In addition, as described above, one embodiment of the present invention and each embodiment are described in detail, but may also include various deformations of the new matters and effects of the present invention that are not unavoidable. This will be familiar to those skilled in the art. It should be easy to understand. That is, all such modifications are included in the scope of the present invention.

For example, a term that appears at least once in a description or a drawing, and a term that is described together with a different term that is broader or synonymous, can be replaced with the different term no matter where in the description or the drawing. In addition, the manufacturing method of the transparent oxide laminated film, the transparent oxide laminated film, and the structure of the transparent resin substrate are not limited to those described in one embodiment of the present invention and each embodiment, and various modifications can be made. .

[Industrial use possibility]

By using the transparent oxide laminate film according to the present invention, a water vapor barrier transparent resin substrate can be formed, and by using the water vapor barrier transparent resin substrate, a liquid crystal display element having a degree of freedom in shape and curved display can be produced. Or electroluminescence display elements (EL display elements), quantum dot display elements (QD display elements), electronic paper, and thin-film solar cells. That is, the present invention is extremely industrially valuable.

Claims (10)

A transparent oxide laminated film is characterized in that a plurality of layers of transparent oxide films containing zinc and tin are laminated, and each layer is composed of an amorphous transparent oxide film having different metal atomic ratios of zinc and tin in each layer. For example, the transparent oxide laminate film according to the first item of the patent application scope includes at least a first transparent oxide film having a metal atomic ratio Sn / (Zn + Sn) of 0.18 or more and 0.29 or less and a metal atomic ratio Sn / ( The second transparent oxide film having Zn + Sn) of 0.44 to 0.90. For example, the transparent oxide laminated film of the second patent application range, wherein at least one of the transparent oxide films contains tantalum and germanium, and the atomic ratio of the foregoing zinc, tin, tantalum, and germanium is Ta / (Zn + Sn + Ge + Ta) is 0.01 or less, and Ge / (Zn + Sn + Ge + Ta) is 0.04 or less. For example, the transparent oxide laminated film of the second scope of the patent application, wherein the film thickness of the transparent oxide laminated film is 100 nm or less. For example, the transparent oxide laminated film according to item 2 of the patent application, wherein the water vapor transmission rate of the transparent oxide laminated film is 0.001 g / m ² according to the differential pressure method specified by the K7129 method of the Japanese Industrial Standard JIS. / day or less. For example, the transparent oxide laminated film of the second patent application range, wherein the aforementioned transparent oxide laminated film has chemical resistance to acids or alkalis, and is immersed in 5% strength hydrochloric acid or 5% strength sodium hydroxide solution. The color difference change value ΔEab before and after the minute is 1.0 or less. For example, the transparent oxide laminated film of the second patent application range, wherein the aforementioned transparent oxide laminated film has chemical resistance to acids or alkalis, and is immersed in 5% strength hydrochloric acid or 5% strength sodium hydroxide solution. The amount of film change before and after the minute was 2.0 nm or less. A method for manufacturing a transparent oxide laminated film, characterized in that sputtering is performed using a target composed of a Sn-Zn-O-based oxide sintered body, and at least a metal atomic ratio Sn / (Zn + Sn) is 0.18 or more The first target of the oxide sintered body of 0.29 or less forms a transparent oxide laminate film with the second target of the oxide sintered body having a metal atomic ratio Sn / (Zn + Sn) of 0.44 or more and 0.90 or less. A transparent resin substrate, characterized in that a transparent oxide laminate film according to any one of claims 1 to 7 is formed on at least one side of a transparent resin substrate. For example, the transparent resin substrate according to item 9 of the patent application scope, wherein the transparent oxide film having a metal atomic ratio Sn / (Zn + Sn) of 0.44 or more and 0.90 or less is the outermost layer.