JPH0218232B2 - - Google Patents

Description

[Detailed description of the invention]

B. Industrial Application Field The present invention relates to a conductive laminate, and more specifically, to a conductive laminate suitable for use in a display device such as a liquid crystal display device. B. Prior Art Transparent conductive films or transparent conductive laminates can be used, for example, as electrodes for liquid crystal displays, electrodes for electroluminescence display devices, electrodes for photoconductive photoreceptors, cathode ray tubes, and window portions of various measuring instruments. It is widely used in the electrical and electronic fields, such as electrostatic shielding layers, antistatic layers, and heating elements. Among these, transparent conductive films having selective light transmittance are used as window materials for collectors for utilizing solar energy or as window materials for buildings due to their infrared light reflecting ability. In addition, with the development of information processing, various solid-state displays using electroluminescence, liquid crystal, plasma, and ferroelectric materials have been developed as display devices to replace cathode ray tubes, and these displays have transparent electrodes. is always used. Furthermore, new electro-optical elements and recording materials that generate interaction or mutual conversion between electrical signals and optical signals are considered to be useful for future information processing technology, but these also have transparency and conductivity. A membrane is required. On the other hand, such transparent conductive films can also be used as window glasses for preventing condensation in automobiles, airplanes, etc., as antistatic films for polymers, glass, etc., and as transparent heat-insulating windows for preventing the dissipation of solar energy. In particular, in recent years, high pixel display elements have been increasing in liquid crystal displays, electroluminescent displays, plasma displays, electrochromic displays, fluorescent displays, etc., and along with this, electrodes made of transparent conductive layers Therefore, it has been proposed to form a signal application line using a low-resistance electrode made of a metal layer at the same time as forming a pixel portion, in order to improve the display speed of the pixel and the image quality. By the way, in display devices such as liquid crystal display devices, patterning of the transparent conductive layer of the conductive laminate is generally done by photo-etching, and in order to remove the photoresist remaining on the conductive laminate, an alkaline solution is used to pattern the transparent conductive layer of the conductive laminate. There is a step of dipping and a step of washing the surface of the conductive laminate with acid after patterning. In these steps, cracks or localized peeling may occur in the transparent conductive layer, which will cause serious defects in the conductive laminate as described below. Although the cause of the above phenomenon is not clearly understood, it is thought that internal stress generated within the transparent conductive layer due to the difference in coefficient of thermal expansion between the substrate and the transparent conductive layer acts. That is, when depositing a transparent conductive layer on a substrate by vapor deposition, the substrate is heated to, for example, 300°C in order to increase the degree of oxidation of the vapor-deposited layer and improve transparency and conductivity.
Heat to the following temperature. Furthermore, the coefficient of thermal expansion of the substrate is 5.5×10 ^-5 cm/cm/℃ for the widely used polyether sulfone (PES) and 1.5×10 ^-5 cm/cm/℃ for polyethylene terephthalate (PET). On the other hand, indium oxide (In ₂ O _x , X≦
3) and that of indium-tin oxide (ITO)
The difference in thermal expansion coefficient between the substrate and the transparent conductive layer is large, on the order of 10 ^-6 cm/cm/°C. Therefore,
It is thought that internal stress is generated in the transparent conductive layer at room temperature due to contraction of the substrate, and that this internal stress causes corrosion to progress in the acid or alkaline solution, causing cracks and local peeling. On the other hand, a two-layer transparent conductive film has been proposed in which an indium oxide film is formed on a transparent substrate and then a tin oxide film is formed (Japanese Patent Laid-Open No. 52-22789).
However, when this transparent conductive film is used, for example, as a transparent electrode plate for a liquid crystal display device element, the temperature is set to 500°C or higher to firmly seal the panel using a glass sealing material.
The purpose is to maintain good transparency and conductivity after this heat treatment. In this transparent conductive film, if there are pinholes or cracks in the tin oxide layer, the resistance to the aforementioned acids and alkalis will decrease; side etching will be large due to the difference in solubility between the indium oxide layer and the tin oxide layer. , patterning is difficult; when an indium oxide layer is provided on the substrate side, both acid resistance and alkali resistance are unsatisfactory, and as a result, the transparent conductive film is likely to crack or peel. C. Purpose of the Invention The present invention aims to solve the above-mentioned problems of conventional conductive laminates and to provide a conductive laminate that exhibits sufficient resistance to acids and alkalis. . D. Structure of the Invention That is, the present invention provides a transparent conductive layer on a substrate, comprising an intermediate layer having a tin content of 7 atomic % or more, and an indium-tin oxide or indium oxide having a tin content of 10 atomic % or less. layers are provided in this order from the substrate side, and the tin content of the intermediate layer is higher than the tin content of the transparent conductive layer. The above-mentioned "substrate" is a substrate whose coefficient of thermal expansion is clearly different from that of the transparent conductive layer, and its material is a polymeric organic material such as polyethylene terephthalate (PET), polyethylene naphthalate, polyhexamethylene. diamide, poly-γ
- Butyroamide, polymethaxylene diamine terephthalamide, aromatic polyester or aromatic polyester carbonate whose main components are bisphenol A and its halide and acid dichloride, copolymers of metaphenylene diamine and isophthalic acid and terephthalic acid, etc. polyamide, polycarbonate, polypropylene, polyimide, polyamide, imidopolybenzimidazole, polyethersulfone (PES), polyetheretherketone, polysulfone, polyetherimide,
Triacetylcellulose can be used. It may have a deflection filter function, and if stretching is required during production, both uniaxial and biaxial properties can be used. A plurality of polymer resins may be laminated or mixed on the surface of the substrate opposite to the surface on which the intermediate layer or transparent conductive layer is formed, or between the substrate and the intermediate layer. For example, it is possible to laminate a vinylidene chloride resin saran coat as a barrier layer to prevent water permeation, and it is also possible to laminate layers having other functions, such as anti-reflection, anti-scratch effects, and gas barrier resin. . For example, when a polyvinylidene chloride material made of Saran Latex (registered trademark) L520 and L511 manufactured by Asahi Kasei Corporation is coated with a wire bar on a polymer film substrate, the effect of preventing water permeation becomes extremely large. The coating conditions include, for example, the substrate is a PET or PES film with a thickness of 100 μm, the Saran latex stock solution (solid content 48%) is diluted 1.0 to 3 times with water, the wire bar wet film thickness is 3 to 20 μm,
The conveyance speed may be 100 to 200 m/min, the drying temperature may be 90 to 140° C. with hot air, and the dry coating layer thickness may be 1 to 30 μm. The thickness of the base is preferably about 100 μm. In ₂ O ₃ and the above-mentioned ITO are used as materials for the transparent conductive layer.
is suitable. Also, its thickness is 200~10000Å
However, 200 to 1000 Å is particularly suitable. However, in the case of ITO, it is better to keep the tin content to less than 10 atom%, and in addition to the above components, Cd, Zn, Al
Those containing the like can also be used. As the material for the intermediate layer, tin oxide or ITO can be used, and the tin content is preferably 7 atomic % or more, particularly preferably 10 atomic % or more. Further, like the transparent conductive layer described above, a layer containing Cd, Zn, Al, etc. can also be used. FIG. 1 shows a cross section of a conductive laminate 1 according to the invention, in which an intermediate layer 3 and a transparent conductive layer 4 are successively deposited on a substrate 2. FIG. Between the intermediate layer 3 and the transparent conductive layer 4, for example, an Al ₂ O ₃ layer, a layer made of another inorganic substance, a layer made of a polymeric substance, etc. are provided to improve the light transmittance due to the optical interference effect. Other intermediate layers may also be provided. E Example In the following, indium oxide or
An example using ITO will be explained. First, the progress that led to the completion of the present invention will be explained. In all of the tests below, the substrate has a thickness
PES with a thickness of 100 μm was used, and the intermediate layer and transparent conductive layer were formed by reactive vapor deposition or reactive sputtering. Test 1 Regarding a conventional conductive laminate without an intermediate layer, the relationship between the tin content of the transparent conductive layer and the sheet resistance was determined. However, the film formation temperature (substrate temperature during vapor deposition)
The temperature is 10 to 200°C, and the film thickness is 600 Å. The test results are shown in Figure 2. Sheet resistance _R0 is 100Ω/ for tin content up to 7 atomic%
□ shows an almost constant value, and when this exceeds 7 atomic%, the resistance gradually increases, and at 10 atomic% it reaches 170Ω/
Reach □. When the tin content exceeds 10 atomic %, the sheet resistance rapidly increases, making it difficult to control the sheet resistance at a constant level and making it impossible to maintain a low resistance value. Therefore, the tin content of the transparent conductive layer should be 10 atomic % or less, and preferably 7 atomic % or less. Test 2 (i) Regarding a conventional conductive laminate without an intermediate layer, the relationship between the substrate temperature during film formation (film formation temperature) and the change in sheet resistance before and after immersion in acid was determined. However, the transparent conductive layer contains 10 atom% of tin, in this example
In ₂ O ₃ , film thickness is 600 Å, acid is 0.05N hydrochloric acid, temperature is
The temperature is 20°C and the immersion time is 30 minutes. The test results are shown in Figure 3. The figure also shows the film forming temperature (Table 1) with respect to the tin content of ITO, which will be described later. R ₀ is the sheet resistance before immersion in acid, and R is the sheet resistance after immersion in acid. R ₀ is 100~300Ω/
□, the light transmittance before acid immersion is 82% at a wavelength of 5500 Å (the same applies hereinafter). When the film formation temperature Ts is lower than 90℃, R/R ₀ is Ts
It increases rapidly as the value decreases. When Ts exceeds 90°C, R/R ₀ decreases to about 2.0, and when Ts exceeds 150°C, R/R ₀ increases slightly. Ts is 90℃
This is because at lower temperatures, the solubility of the transparent conductive layer in the subsequent layer becomes greater, and as Ts becomes higher, the above-mentioned solubility decreases. Furthermore, when Ts exceeds 150°C, although the solubility described above decreases, R/R ₀ increases because rapid cracking occurs in the transparent conductive layer. (ii) R/R ₀ is preferably closer to 1, and preferably 2.0 or less. Regarding the conductive laminate using indium oxide or ITO as the transparent conductive layer material,
R/R ₀ was determined in the same manner as in (i), and the film forming temperature that satisfied R/R ₀ ≦2.0 was investigated, and the results shown in Table 1 below were obtained. The tin content in ITO was set to 10 atomic % based on the results of Test 1 above.

[Table] Shown.
From the table, it can be seen that the higher the tin content of the transparent conductive layer, the more it is necessary to raise the film-forming temperature. Furthermore, the higher the film formation temperature, the lower the solubility in acids and the lower R/R _0. However, as described in (i) above, the higher the film formation temperature, the more cracks appear. The same is true for . The reason why cracks occur in the transparent conductive layer as the film forming temperature increases is that the internal stress generated in the transparent conductive layer increases due to the difference in thermal expansion coefficient between the substrate and the transparent conductive layer, and this is caused by acid immersion. This is thought to be caused by inducing cracks to form at the same time. As can be seen from the results (i) and (ii), increasing the film formation temperature lowers R/R ₀ , but there is a tendency for cracks to occur. If the cracks that occur in the transparent conductive layer are minute, the increase in R/R ₀ will be small;
When patterning a transparent conductive layer into a fine pattern (especially when fine wiring is provided),
Even minute cracks can cause disconnection, resulting in areas inoperable in liquid crystal display devices and other display devices using this conductive laminate. In such cases, even minute cracks are serious defects for the conductive laminate. In view of the above circumstances, it would be extremely advantageous if cracking could be prevented even if the film formation temperature was raised. Test 3 Regarding the conductive laminate 1 having the structure shown in FIG. 1, the material of the intermediate layer 3 was ITO, and the tin content of the intermediate layer was examined so that cracks and peeling would not occur in the transparent conductive layer 4 due to acid immersion. However, the transparent conductive layer 3 contains 0 to 8 tin.
Indium oxide or ITO containing atomic%, film formation temperature 90-300℃, especially 100-200℃ (100℃ for 0 atomic% Sn, 200℃ for 6 atomic% Sn), thickness 400 Å
It is. The film forming temperature of the intermediate layer 3 is 20 to 200°C (preferably
50-100℃), and the thickness is 200 Å. Perform acid immersion in the same manner as in Test 2 above to determine that R/R ₀ ≦
2.0, and the tin content in the intermediate layer that would not cause cracks or peeling in the transparent conductive layer was determined. The results are shown in Table 2 below. The same table also lists the film-forming temperature Ts.

【table】

[Table] The following can be understood from Table 2. In order to satisfy the above conditions, the higher the tin content of the transparent conductive layer, the higher the tin content of the intermediate layer must be, and the tin content of the intermediate layer is always higher than that of the transparent conductive layer. There is a need to. This fact is due to the fact that the higher the tin content of the transparent conductive layer, the higher the film forming temperature needs to be (see Test 2 above), and the difference in thermal expansion coefficient between the transparent conductive layer and the substrate causes the formation of tin in the transparent conductive layer. This is due to the fact that the internal stress increases, and by providing an intermediate layer with a higher tin content between the substrate and the transparent conductive layer, the internal stress is alleviated and cracking and peeling when immersed in acid are prevented. It can be thought of as a thing. Test 4 Regarding the conductive laminate 1 having the structure shown in FIG. 1, the material of the intermediate layer 3 was tin oxide, and the relationship between its thickness and the change in sheet resistance R/R ₀ before and after immersion in acid was determined. The transparent conductive layer 4 was the same as in Test 3 above. R ₀ is 400-600Ω/□, and the light transmittance before acid immersion is 82-75%. Measuring film thickness
For thicknesses of 300 Å or more, Talystep was used, and for thicknesses less than 300 Å, the thickness was determined by calculation from the evaporation rate and film formation time (the same applies to subsequent tests). The test results are shown in Figure 4. When the interlayer thickness is less than 80 Å, R/
R ₀ rises rapidly. This is the result of a large number of cracks (some of which cause peeling) in the transparent conductive layer due to acid immersion. When the thickness of the intermediate layer is 80 Å, R/R ₀ is 1.4, and as this thickness increases, R/R ₀ becomes smaller, and at 500 Å or more, R/R ₀ becomes 1. No cracks were observed in the transparent conductive layer when the intermediate layer thickness was 80 Å or more. When the material of the intermediate layer was ITO containing 10 atomic % of tin, almost the same results as above were obtained. From the above results, it can be understood that the thickness of the intermediate layer is preferably 80 Å or more. Test 5 Regarding the conductive laminate 1 having the structure shown in Fig. 1, the material of the transparent conductive layer 4 was indium oxide or tin.
ITO containing less than 10 atomic %, for example 6 atomic %,
Its thickness was set to 400 Å. The film forming temperature is 100~
140℃, the latter at 200℃. The material of the intermediate layer 3 is 7 at% or more, in this example, tin oxide, and its thickness and change in sheet resistance after immersion in a 5% by weight KOH aqueous solution (20°C) for 10 minutes R/R ₀
The surface condition was observed to determine the relationship between the two. The film forming temperature of the intermediate layer is 20 to 200°C, in this example 50 to 100°C. The scene resistance R ₀ before immersion in KOH aqueous solution is 400 to 300 Ω/
□, light transmittance is over 80%. The test results are shown in Table 3 below. In the same table, ○, △, and × indicate the following conditions (the same applies to subsequent tests) ○: R/R ₀ ≦2.0, no cracks or peeling observed △: R/R ₀ ≦ 2.0, No cracks or peeling observed ×: R/R ₀ >2.0, Both cracks and peeling occurred

[Table] When the intermediate layer thickness is 70 Å or more, R/R ₀ is less than 2.0, and no cracks or peeling are observed. Test 6 Regarding the conductive laminate 1 having the structure shown in FIG. 1, the material of the intermediate layer 3 was indium oxide, ITO with a tin content of 1 to 30 at%, or tin oxide,
Deposition temperature: 20 to 2000℃ (70℃ in this example) Thickness:
200 Å, and the transparent conductive layer 4 and the others were the same as in Test 5 above.
A similar test was conducted to determine the relationship between the tin content of the intermediate layer 2 and the alkali resistance. Sheet resistance _R0 before KOH immersion is 400-300Ω/□, light transmittance is
80% or more. The test results are shown in Table 4 below.

[Table] When the tin content of the intermediate layer is 7% or more, R/R ₀ is less than 2.0, and no cracking or peeling is observed. The results of Tests 1 to 6 above are summarized as follows. (a) In order to improve acid resistance, (1) the tin content of the intermediate layer is higher than that of the transparent conductive layer, at least 7 atomic %, preferably 10 atomic %;
The above shall apply. (2) The thickness of the intermediate layer should be 80 Å or more, and the film formation temperature should be below the temperature that the substrate can withstand. For example, in PES, the temperature should be 200℃ or less. (3) The tin content of the transparent conductive layer is 10 atomic % or less, preferably 7 atomic % or less. (4) The film-forming temperature of the transparent conductive layer is preferably set higher as the tin content increases, and the temperature is set as shown in Table 1 according to the tin content. However, the temperature that the substrate can withstand, for example, 200°C or less in the case of PES. (b) In order to improve alkali resistance, (5) Same as (1) above, (6) The thickness of the intermediate layer should be 70 Å or more, and
Same as (2). The present invention has been made based on the above findings. Next, specific examples of the present invention will be described. Using the vapor deposition apparatus shown in Figure 5, a water permeation prevention layer made of vinylidene chloride resin with a thickness of 1 to 30 μm, for example 20 μm, is preliminarily coated on one side.
An intermediate layer and a transparent conductive layer were sequentially deposited on the surface of a 100 μm PES sheet substrate opposite to the water permeation prevention layer to obtain a transparent conductive laminate. The vapor deposition apparatus is partitioned into chambers 30, 31b, 31a, and 32, and a take-up roll 36 and a supply roll 33 for the sheet substrate 2 are arranged in the chambers 32 and 30 on both sides, and the substrate 2 is sequentially transferred between the two rolls. The following processing is performed while the data is being sent. First, the sheet substrate 2 is conveyed in a meandering manner by five conveyance rollers 26 in the chamber 30, and is preheated by a halogen heat lamp 27 disposed between the sheet substrates 2 to adsorb the sheet substrate 2. Moisture is removed and the material is subjected to electrical discharge treatment in the electrical discharge device 25 to be cleaned. The operating conditions within the chamber 30 are as follows. Heating temperature: 80 ~ 150℃, degree of decompression: 10 ^-4 ~
10 ^-5 Torr, Discharge treatment: Gas used is O ₂ gas, Ar gas or Ar
+O ₂ mixed gas, DC or AC discharge (0 to 1000W (0W means no discharge treatment)) Next, the sheet substrate 2 is transported into the chamber 31b,
The evaporation source 42b is maintained at a predetermined temperature in close contact with a constant temperature roller 29 (controllable between -0°C and 250°C).
The intermediate layer is formed by vapor deposition using the vapor generated from the wafer. The thickness of the intermediate layer is detected and controlled by a crystal vibrating film thickness monitor 28. The operating conditions within the chamber 31b are as follows. Evaporation source 42b: Sn, binary evaporation of Sn and In,
SnO ₂ or ITO containing 7 at% or more of Sn Heating method: Electron gun heating (SnO ₂ or ITO)
Resistance heating (binary vapor deposition of Sn or Sn, In) Gas discharge device 37: High frequency discharge (details will be described later) Evaporation rate: 100 x 1000 Å/min Oxygen pressure: 5 x 10 ^-4 ~ 3.0 x 10 ^-2 Torr High frequency power: 200~800W (13.56MHz) Substrate holding temperature: 20~200℃, 50~100℃ in this example
C. Next, the sheet substrate 2 is conveyed into a chamber 31a having the same structure as the chamber 31b, and a transparent conductive layer is formed on the intermediate layer. The operating conditions within the chamber 31a are as follows. Evaporation source 42a: ITO with In or Sn 10 atomic % or less Heating method: Electron gun heating or resistance heating discharge device 37: Same as above Evaporation rate: 100 to 2000 Å/min Oxygen pressure: 3 × 10 ^-4 to 3 × 10 ^{- 3} Torr High frequency power: Same as above Substrate holding temperature: If the evaporation source does not contain Sa, 90°C or higher, e.g. 130°C; if the evaporation source contains 5 at% Sn, 180°C or higher, e.g. 190°C Otherwise, room temperature The same is true within 31b. Finally, the sheet substrate 2 is transported into the chamber 32,
The sheet resistance monitor 24 measures the sheet resistance between the two conveyance rollers 26, and the sheet resistance is measured between the two conveyance rollers 26.
It is wound up. The details of the high frequency discharge device 37 arranged in the chambers 31b and 31a are as follows. As shown in FIG. 6, the discharge electrode consists of a plurality of rings 45a and 45b arranged to enclose the circumferential surface of the gas (oxygen) introduction tube 43. A water-cooled tube is wrapped around the entire discharge device 37 to cool it, but this water-cooled tube is not shown. One ring-shaped electrode 45a is connected to the high frequency introduction terminal 48 by a lead wire 67, and the other ring-shaped electrode 45b is connected to the metal anti-corrosion member 44 by a lead wire 58, and the metal mounting plate 39 is connected to the metal attachment plate 39. is grounded through. The above electrodes 45a, 45b
For example, it consists of a band ring made of copper, stainless steel, or platinum with an inner diameter of 2 to 10 cmφ and a width of 0.5 to 10 cm,
A C-coupling type (capacitive coupling type) discharge is generated within the introduction tube 43. By wrapping a water-cooled tube around the band ring and cooling it, high-power and high-frequency waves can be introduced for a long period of time. The reactive vapor deposition method using the gas discharge device 37 as described above has the following features (1) to (6) as compared to conventional methods. (1) Since the reaction gas is activated or ionized by applying a high frequency voltage to the discharge device, it is possible to increase the reactivity of the reaction gas and promote the reaction with the vapor deposition material, and at the same time, in the discharge section, the discharge electrode 45 can be provided at a position not in contact with the discharge area. Therefore, the electrode 45 is not bombarded during discharge, and the electrode material does not mix into the gas and contaminate the deposited film. On the other hand, it is conceivable to apply a DC voltage to the discharge device to cause discharge, but in this case it is inappropriate because the electrodes need to be placed in contact with the discharge region. (2) By arranging the discharge electrode 45 around the outer circumference of the introduction tube 43, the gas inside the introduction tube 43 can be efficiently ionized or activated while keeping the gas pressure high without increasing the gas pressure in the vapor deposition space. can. Therefore, it is also possible to increase the amount and rate of gas introduction. In addition, the gas pressure in the evaporation space can be lowered, eliminating the need for electric field acceleration of the evaporation material, making it possible to use both metals and oxides as the evaporation material, widening the range of selection, and allowing the material of the substrate to be evaporated to be applied over a wide range of materials. In addition to making it possible to select a high-quality vapor deposition film, it is possible to form a high-quality vapor deposition film. Moreover, the selection range of substrate temperature is widened, and heating and cooling of the substrate can be easily performed. (3) The gas discharge area is limited to the inlet tube 43, and the electrode 4
5, it is possible to prevent the electrode 45 from being bombarded by gas ions generated during discharge. In other words, it is possible to prevent the electrode material from being heated or evaporated by bombardment, thereby preventing contamination of the deposition space. (4) Since the adhesion prevention members 44 and 46 are provided so as to enclose the introduction tube 43 and the electrode 45, the introduction tube 43,
It is possible to prevent evaporated substances from adhering to the electrode 45 and the high-frequency introduction terminal 48, and also to effectively prevent leakage of high-frequency waves through the mounting plate 39, the electrode 45, and the introduction pipe 43, so that discharge can be performed stably. can. (5) Since the gas discharge device 37 can be installed in the bell gear with a simple structure via an installation stand, the installation or removal work becomes easy. Moreover, when depositing a film on a large-area substrate, the installation position,
By adjusting and optimizing the number of particles, uniform film formation becomes possible. For example, a discharge device can be set at an appropriate position, or a plurality of discharge devices can be set for uniform film formation. (6) Since the direction of the gas discharge port can be easily changed, it can be set so that the discharge is not disturbed even when the evaporation rate changes. In particular, if the gas discharge device is installed so that the gas discharge port is not directed between the evaporation source and the substrate, the discharge can continue stably and the quality of the deposited film can be made uniform. (7) By cooling the mount, the discharge electrode 45, and the adhesion prevention member 44 with water, heating during discharge can be prevented, high-power radio frequency waves can be introduced, and reactive vapor deposition can be promoted. In this way, as shown in FIG. 7, an intermediate layer 3 and a transparent conductive layer 4 are sequentially formed on one surface of the substrate 2.
A transparent conductive laminate having a water permeation prevention layer 5 formed on the other side was obtained. The sheet resistance, light transmittance, and acid resistance and alkali resistance of the obtained transparent conductive laminate were evaluated in the same manner as in Tests 5 and 6 under the operating conditions in the chambers 31b and 31a described above. Ivy. Examples of the results are shown in Table 5 below. In the same table, Ts is the substrate holding temperature and RF is the high frequency power.

【table】

【table】

[Table] Comparative Examples 1 and 2 do not contain Sn in the intermediate layer, and as a result, acid resistance and alkali resistance are not good. On the other hand, all of the examples that satisfy the above-mentioned conditions have excellent acid resistance and alkali resistance, and also show sufficiently satisfactory sheet resistance and light transmittance. A polyimide resin film having a heat resistance of 399°C was used as the sheet base, and an intermediate layer with a thickness of 100 Å and a transparent conductive layer with a thickness of 600 Å were formed on the base by the same method as described above (reactive vapor deposition method), and the conveyance speed was set to 50 cm/min. The layers (all made of ITO) were sequentially deposited to form a transparent conductive laminate. The obtained transparent conductive laminate exhibited good properties as shown in Table 6 below. Note that since the intermediate layer was formed at a high substrate holding temperature Ts of 230° C., the results of the X-ray diffraction test showed that the intermediate layer was crystalline.

[Table] The above example is an example in which two layers, an intermediate layer and a transparent conductive layer, are laminated, but the tin content and film formation temperature are changed continuously from the intermediate layer to the transparent conductive layer. You can also do it. The relationship between the distance from the base surface of the conductive laminate thus formed and the tin content is shown in FIG. 8, for example. In the figure, curve A
curves B, C, D and E indicate the tin content of layers in which the tin content was continuously varied. Tin content 7
The range of ~10 atomic % is the boundary region between the intermediate layer and the transparent conductive layer. Curves B, C, D, or E can be obtained by continuously changing the deposition operating conditions. In the film forming chamber 31b shown in FIG. 5, the evaporation source 42b is replaced with a tin or tin oxide evaporation source 4 as shown in FIG.
2b-1 is provided on the introduction side of the substrate conveyance, and on the other hand, the indium or indium oxide evaporation source 42b-2 is provided on the substrate delivery side, so that curves B, C,
The tin concentration distributions shown in D and E are obtained. FIG. 10 shows an example of a liquid crystal display device in which the transparent conductive layer and intermediate layer of the conductive laminate according to the present invention are etched into a predetermined pattern. A transparent conductive laminate 1 is formed by sequentially laminating a patterned intermediate layer 3 and a transparent conductive layer 4 on a transparent substrate 2, with the transparent conductive layers 4 facing each other,
A liquid crystal display device 9 is configured in a sandwich-like structure with a liquid crystal 6 sandwiched therebetween via an alignment film 7. A water permeation prevention layer 5 and a deflection film 8 are sequentially applied to both sides of the transparent substrate 2. The conductive laminate according to the present invention is suitable for use not only in liquid crystal display devices but also in various display devices such as electroluminescent display devices, electrochromic display devices, and fluorescent display devices. F. Effects of the Invention As explained above, the conductive laminate according to the present invention provides an intermediate layer between the base and the transparent conductive layer,
Since the tin content of this intermediate layer is 7 at % or more and higher than the tin content of the transparent conductive layer, chemical resistance is imparted by the inclusion of this large amount of tin. As a result, it has a high resistance to acids and alkalis, and can be used in liquid crystal display devices, for example, without causing cracks or peeling on the surface during post-patterning processing, and can be used with full reliability. can.

[Brief explanation of drawings]

The drawings all show examples of the present invention, and FIG. 1 is a cross-sectional view of a conductive laminate, FIG. 2 is a graph showing the relationship between tin content and sheet resistance of a transparent conductive layer, and FIG. Figure 3 is a graph showing the relationship between the film formation temperature of the transparent conductive layer and the change in sheet resistance due to acid immersion, and Figure 4 is a graph showing the relationship between the film thickness of the tin oxide intermediate layer and the change in sheet resistance due to acid immersion. , Fig. 5 is a schematic cross-sectional view of the vapor deposition apparatus used for film formation, Fig. 6 is a perspective view of the gas discharge device in the vapor deposition apparatus, Fig. 7 is a cross-sectional view of another conductive laminate, and Fig. 8 is a cross-sectional view of another conductive laminate. A graph showing an example of the relationship between the distance from the substrate surface and the tin content in the layer, Figure 9 is a schematic partial cross-sectional view of another vapor deposition apparatus used for film formation, and Figure 10 is a cross-sectional view of a liquid crystal display device. It is. In addition, in the symbols shown in the drawings, 1... conductive laminate, 2... base, 3... intermediate layer, 4...
Transparent conductive layer, 5...Water permeation prevention layer, 6...Liquid crystal, 7
... alignment film, 8 ... deflection film, 9 ... liquid crystal display device, 29 ... constant temperature roller, 37 ... gas discharge device, 42a, 42b ... evaporation source.

Claims (1)

[Claims] 1 On the substrate, an intermediate layer with a tin content of 7 at % or more and an indium layer with a tin content of 10 at % or less
A transparent conductive layer made of tin oxide or indium oxide is provided in this order from the base side, and the tin content of the intermediate layer is higher than the tin content of the transparent conductive layer. Sex laminate.