KR100736664B1 - Substrate with ITO transparent conductive film and method for producing same - Google Patents

Abstract

A method of forming an ITO transparent conductive film on a substrate using an ion plating apparatus includes the steps of (a) generating a plasma beam from a voltage gradient plasma gun into a vacuum chamber, (b) irradiating the ITO source with the plasma beam, Heating and evaporating, (c) ionizing the evaporated ITO source in a plasma atmosphere, and (d) depositing the ionized ITO source on a substrate to form an ITO transparent conductive film on the substrate. It includes. Wherein the temperature of the substrate is adjusted to 80 to 145 ° C. during at least step (d), and the radiant heat incident on the substrate from the ITO source during at least step (d) is 1.5 to 10.0 J / cm ² per unit time and unit area. Adjust to min The resulting ITO transparent conductive film has a resistivity of 1.2 × 10 ⁻⁴ to 3.0 × 10 ⁻⁴ Ω.cm.

 ITO, conductive film, plasma gun

Description

Substrate with ITO transparent conductive film and method for producing same

1 is a schematic diagram showing an apparatus for forming a film by ion plating (active reaction deposition) using a voltage gradient plasma gun.

2 is a schematic showing another apparatus for forming a film by ion plating (active reaction deposition) using a voltage gradient plasma gun.

3 is an enlarged cross-sectional view showing an ITO transparent conductive film formed on a substrate made of an organic polymer or the like.

The present invention relates to a method of forming an ITO transparent conductive film on a substrate for use in flat panel displays, electrical devices, solar cells, optical devices, and the like. In particular, it relates to a method of forming an ITO transparent conductive film on a substrate comprising an organic polymer film.

Transparent conductive films are an essential and important element in flat panel displays and solar cells because of their inherent properties of passing light and conducting electricity.

In many cases, ITO transparent conductive films are formed by vacuum film forming methods. Examples of vacuum film forming methods for forming an ITO transparent conductive film include ion plating, sputtering, and vacuum deposition. Of these, the sputtering method is most widely used.

For the production of ITO transparent conductive films by the sputtering method, JP-A-9-171188 provides an ITO transparent conductive film having a low resistance of 2 × 10 ⁻⁴ Ω.cm by heating the substrate at a temperature of 300 ° C. or higher. A method is disclosed.

JP-A-9-25575 and JP-A-2000-17430 are methods for obtaining low resistance ITO transparent conductive films by heating the substrate at a relatively low temperature of about 200 ° C. and ion plating with a voltage gradient plasma gun. Is starting.

In the technical field of displays and electrical devices, conventional inorganic substrates (e.g. glass) may be used between several inorganic substrates in order to make devices that are lighter in weight, thinner in thickness, and more flexible. Various proposals have been made to substitute an organic substrate composed of one polymer selected from sandwiched substrates or various polymers. Nowadays, many devices are becoming more and more complicated structures. In some cases, organic devices are being formed on inorganic substrates, such as LCD color filters.

In the case of using an organic polymer substrate as mentioned above, a substrate containing an organic material formed on or between inorganic materials, these substrates are heat resistant compared to a substrate made of an inorganic material (for example, glass). There is a lack of this problem. Thus, the substrates may be poor, or may cause a problem that when the substrate is heated to near its melting point, its mechanical and electrical properties (eg, modulus of elasticity, refractive index, diffusion coefficient, and dielectric constant) are greatly deformed.

Therefore, when using a substrate having an organic polymer, it was necessary to lower the substrate to a temperature of 200 ° C or lower. For this reason, it was difficult to lower the resistance of an ITO transparent conductive film during film formation by the sputtering method.

It is known that ion plating using voltage gradient plasma guns can produce low resistive films even when the substrate temperature is relatively low. However, during fabrication of the ITO transparent conductive film, the substrate temperature increases rapidly due to the dense plasma beam emitted from the voltage gradient plasma gun and the radiant heat from the ITO evaporation source. To prevent this increase in temperature, the transport speed of the substrate can be increased (see JP-A-10313810). In this case, to produce an ITO transparent conductive film having a desired film thickness, it is necessary to have a very fast film formation rate. Therefore, it is necessary to increase the power applied between the anode and the cathode when using a voltage gradient plasma gun. Therefore, the amount of thermal projection on the substrate increases with radiation from the high density plasma beam and the ITO evaporation source. Thus, during film formation, the substrate temperature can quickly increase to the melting point of the organic polymer. This can cause damage to the original shape of the substrate. In addition, cracking gas can be produced, for example, from the substrate. In addition, the conductivity of the ITO transparent conductive film can be extremely low.

In order to solve the above problems of the prior art, the present invention provides a method of effectively forming an ITO transparent conductive film on a substrate having an organic polymer.

Method for forming an ITO transparent conductive film on a substrate using an ion plating apparatus according to one feature of the present invention for solving the above technical problem is

(a) generating a plasma beam from the voltage gradient plasma gun into the vacuum chamber;

(b) irradiating an ITO source with the plasma beam to heat and evaporate the ITO source;

(c) ionizing the evaporated ITO source in a plasma atmosphere; And

(d) depositing the ionized ITO source onto a substrate to form an ITO transparent conductive film on the substrate.

Wherein the temperature of the substrate is adjusted to 80-145 ° C. during at least step (d), and the radiant heat incident on the substrate from the ITO source during at least step (d) is 1.5-10.0 J / cm ² per unit time and unit unit area. Adjust to min

Wherein the resultant ITO transparent conductive film formed by the method comprises indium oxide doped with 5-10 wt% tin in the form of oxide, wherein the ITO transparent conductive film is 1.2 × 10 ⁻⁴ to 3.0 × 10 ⁻⁴ Ω has a resistivity of .cm.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention.

The ion plating apparatus for film formation, shown in FIG. 1, is used to carry out the method of the present invention. The ion plating apparatus according to the embodiment of the present invention is disposed on the bottom of the vacuum chamber 1, the pressure gradient type plasma gun (2) connected to the side wall of the vacuum chamber (1), the vacuum chamber (1) A crucible 3, a substrate holder 4 disposed above the vacuum chamber 1, and a vacuum evacuation device 17.

The interior of the crucible 3 is filled with an ITO source 19 (eg, ITO mass). This indium tin oxide (ITO) can be defined as indium oxide doped with tin. Tin is here in oxidized form, the content of which may be 5 to 10% by weight relative to 100% by weight of total ITO. A permanent magnet 22 for deflecting or concentrating the plasma beam 12 is disposed at the bottom of the crucible 3. In addition, the vacuum exhaust device 17 is connected with the vacuum chamber 1 through the conductance valve 16 to exhaust the vacuum chamber 1. In the embodiment of the present invention, in order to obtain a specific opening of the conductance valve 16 based on a measurement of the vacuum gauge 18 attached to the vacuum chamber 1, the pressure of the vacuum chamber 1 is exhausted. It is preferable to adjust to 0.05 to 0.3 Pa.

It is economically undesirable to maintain the pressure of the vacuum chamber 1 at 0.05 Pa or less, because it causes excessive burden on the vacuum exhaust device 17 and the vacuum chamber 1 must be provided to have an unnecessary volume. If the pressure in the vacuum chamber 1 exceeds 0.3 Pa during step (d), the evaporated ITO source will collide with very many argon gas molecules and very many oxygen gas molecules until it reaches the substrate. Thus, the evaporated ITO source loses substantially energy. This can make the conductivity of the ITO transparent conductive film deposited on the substrate 25 extremely low. Therefore, the pressure is preferably at least 0.3 Pa in step (d), preferably 0.3 Pa or less, more preferably 0.15 Pa or less in steps (b), (c) and (d).

The voltage gradient plasma gun 2 has a cylinder tube 9 whose one end is sealed with a cathode 8. A cylinder 7 made of molybdenum is fixed to the cathode 8. The cylinder 70 has a pipe 5 made of tantalum (Ta) at the center of the shaft, and a disk 6 made of LaB ₆ at the inner end thereof. These pipes 5 and disks 6 are mounted to the cylinder 7. The cathode 8 is connected to the cathode of the power supply 10 for discharging. The crucible 3 at the bottom of the vacuum chamber 1 is connected to the anode of the power source 10 and serves as an anode. During the formation of the ITO transparent conductive film, the argon gas 20 is introduced through the pipe 5 and discharge is made between the cathode 8 of the voltage gradient plasma gun and the crucible 30 (anode) in the vacuum chamber to form a plasma beam ( 12) form.

The plasma beam 12 is formed by a ring focusing coil 21 for contracting the cutting plane of the plasma beam, and a permanent magnet for refracting and concentrating the plasma beam 12 with the ITO source 19. Concentrated to ITO source 19. The concentrated plasma beam 12 then heats and evaporates the ITO source 19.

The substrate holder 4 as seen in FIG. 1 is provided to be rotatable by a motor (not shown). Above the substrate holder 4, a heater 11 and a thermometer 13 for heating the substrate 25 are provided. The heater 11 maintains the substrate 25 at a predetermined temperature (for example, 80 to 145 ° C). The output of the heater 11 is adjusted based on the temperature measured by the thermometer 13. The heater 11 may be a lamp heater such as a tungsten halogen lamp, a xeon arc lamp, and a graphite heater.

In order to heat the substrate 25 to a predetermined temperature, it is possible to create a measurement curve prior to film formation, for example as described below. Prior to step (a), the substrate 25 is preheated. During preheating, the temperature (actual temperature) of the substrate 25 is measured by a temporary thermometer (eg, a thermocouple) temporarily attached to the substrate 25. Simultaneously with this measurement, the approximate temperature of the substrate 25 is also measured by the thermometer 13 located in proximity to the substrate 25. And a measurement curve is calculated | required from actual and approximate temperature. Then, the temporary thermometer is removed from the substrate 25. The measurement curve gives the actual temperature from the approximate temperature. In at least step (d) only the approximate temperature is measured from the thermometer 13. Thus, the temperature of the substrate is determined from the measurement curve as an estimate of the actual temperature. This estimated actual temperature is adjusted to 80 to 145 ° C by adjusting the output of the heater 11.

The oxygen gas introduction nozzle 14 is attached to the side wall of the vacuum chamber 1. If necessary, the oxygen gas 15 is supplied to the vacuum chamber 1 through the oxygen gas introduction nozzle 14 using a mass flow controller (not shown).

The voltage gradient plasma gun 2 always maintains the internal pressure of the voltage gradient plasma gun 2 to a level higher than that of the vacuum chamber 1, and the oxygen gas 15 is always filled with argon gas to fill the interior of the plasma gun 2. ) To prevent the pressure drop caused by Due to this structure, it is possible to prevent the oxygen gas 15 from oxidizing and deteriorating the pipe 5 made of tantalum of the plasma gun 2 and the disk 6 made of LaB ₆ in a high temperature exposure environment.

As shown in FIG. 3, it is possible to form the ITO transparent conductive film 24 on the surface of the substrate 25 using the ion plating apparatus of FIG. 1. The substrate 25 may be composed entirely of an organic polymer, or may be a composite including an inorganic material as a basic configuration and an organic polymer as a microstructure.

In the above, the organic polymer is not particularly limited. Examples include polymer plastic resins such as polyethylene terephthalate, polycarbonate, polymethyl methacrylate, polyethylene naphthalate, polyether sulfone, nylon, polyallylate, or cycloolefin polymers. Such organic polymers can be used as base films and plates, such as substrate 25.

The surface of the organic polymer constituting the substrate 25 may be corona discharge treated, anchor coated, or casted.

On the other hand, examples of the substrate 25 include a thin film or gas barrier film of an inorganic material (eg, SiO ₂ , SiO _X , SiON, SiN, SiOCN, and SiAlON) formed on an organic polymer, an inorganic material (glass, Ceramic or metal) coated with an organic material having no heat resistance, and an electronic device (for example, an organic EL (electroluminescence) device) formed on a substrate.

The ITO transparent conductive film formed on the substrate 25 may be defined as indium oxide topping with tin. Such tin is in the oxidized form and is 5-10% by weight when the total weight of the ITO film is 100% by weight. In other words, the total weight of indium oxide and tin in the oxidized form is 100% by weight.

If the content of tin (in the form of tin oxide) is less than 5% by weight, the concentration of the carrier in the ITO transparent conductive film becomes too low. If the content of tin (in the form of tin oxide) exceeds 10% by weight, the mobility of the carrier becomes too low. In both cases, the ITO film becomes too low in conductivity. Therefore, the content of tin (in the form of tin oxide) is preferably 5 to 10% by weight.

Hereinafter, according to one embodiment of the present invention, a method of forming the ITO transparent conductive film 24 on the substrate 25 using the film forming apparatus of FIG. 1 will be described.

The crucible 3 formed of carbon is filled with an ITO source 19. The filled crucible 3 is placed at the bottom of the vacuum chamber 1. The ITO source 19 is preferably in lump form, but the form is not particularly limited.

To form an ITO transparent conductive film on the substrate 25, the substrate 25 is attached to the substrate holder 4 and the vacuum chamber 1 is evacuated to a pressure of about 2 × 10 ⁻⁴ Pa. On the vacuum chamber 1, the substrate is heated to a predetermined temperature to remove the gas adsorbed on the surface of the substrate 25 and the gas released from the inside of the substrate 25.

After the evacuation step, argon gas 20 is supplied to the vacuum chamber 1 through the voltage gradient plasma gun 2. At this time, the flow rate of argon gas is adjusted to 10 to 40 cm ³ / min (sccm) using a mass flow controller (not shown).

Thereafter, the oxygen gas 15 is supplied to the vacuum chamber 1 through the oxygen gas supply nozzle 14. At least in step (d), preferably in steps (b), (c) and (d), the pressure in the vacuum chamber 1 is adjusted to 0.05 to 0.3 Pa in order to stably perform film formation. This pressure adjustment of the vacuum chamber 1 is performed by adjusting the exhaust speed to the opening of the conductance valve 16 disposed between the vacuum exhaust device 17 and the vacuum chamber 1.

The flow rate of the oxygen gas 15 is set to an optimum value based on the film formation speed, the output of the voltage gradient plasma gun, the pressure in the vacuum chamber, and the temperature of the substrate 25.

Thereafter, power is applied to the voltage gradient plasma gun 2 to generate the plasma beam 12. The resulting plasma beam 12 is concentrated to the ITO source inside the crucible 3 due to the focusing coil 21 and the permanent magnet 22, and the ITO source 19 is heated to evaporate the ITO source. The evaporated ITO source and introduced oxygen gas 15 are then ionized in the plasma environment 23. Thereafter, the ionized ITO source is deposited on the substrate 25 when opening a shutter (not shown) installed under the substrate 25.

The ionized ITO source is accelerated to the substrate 25 by a potential difference between the plasma potential of the plasma in the atmosphere and the floating voltage of the substrate 25. Thus, an ionized ITO source having a large energy of about 20 eV reaches and deposits on the bottom surface of the substrate 25 to form a low resistance and compact ITO transparent conductive film.

If the temperature of the substrate 25 during step (d) of the method is less than 50 ° C., the resulting ITO transparent conductive film becomes too high in resistance. Such ITO films are difficult to use as devices.

When the substrate 25 is heated to about 80 ° C., the ITO transparent conductive film 24 has a low resistance, thereby improving conductivity. Therefore, it is preferable to heat the substrate 25 to 80 ° C or higher in step (d). When the temperature of the substrate 25 is set to 145 ° C. or higher by the heater 11, the temperature of the substrate 25 may exceed 200 ° C. due to the lamination of ionized ITO on the substrate 25 and radiant heat from the ITO source. have. Therefore, it is preferable to adjust the temperature of the substrate 25 to 145 ° C or less.

While forming the ITO transparent conductive film 24 on the substrate 25, the temperature of the substrate 25 tends to increase rapidly due to the radiant heat radiated from the high density plasma beam 12 and the ITO source 19. In order to prevent such a rapid temperature increase, it is preferable to adjust the amount of heat (radiation heat) applied to the substrate 25 to 10.0 J / cm ² .min or less. The adjustment of this amount of heat can be achieved, for example, by adjusting the power of the power source 10 applied to the cathode 8 and the crucible 3 (anode) to energize the voltage gradient plasma gun 2. In order to achieve an ITO transparent conductive film having excellent conductivity, it is preferable to adjust the heat amount (radiation heat) to 1.5 J / cm ² .min or more.

In general, it is possible to adjust the pressure in the vacuum chamber by adjusting the exhaust speed of the exhaust device provided in the vacuum chamber, or by adjusting the amount (speed) of the gas introduced into the vacuum chamber. However, in the present invention, as described below, the former (ie exhaust rate control) is preferred to the latter (gas introduction rate control).

When the pressure in the vacuum chamber 1 is adjusted by adjusting the exhaust speed of the vacuum exhaust device 17 provided in the vacuum chamber 1, it is possible to maintain the oxygen gas partial pressure at a substantially constant level. On the contrary, when the pressure in the vacuum chamber 1 is adjusted by adjusting the gas introduction rate, the oxygen partial pressure in the vacuum chamber 1 may be changed.

When the amount of oxygen in the ITO transparent conductive film is reduced, the conductivity of the film is also lowered. In addition, the light transmitted through the ITO transparent conductive film becomes brown. Thus, the light transmission of the film is also lowered. As the amount of oxygen in the ITO transparent conductive film increases, the transmitted light becomes colorless, but the conductivity becomes low. Therefore, it is desirable to adjust the amount of oxygen in the ITO transparent conductive film to an optimum value.

In order to control the amount of oxygen in the ITO transparent conductive film to an optimum value, it is desirable to maintain the oxygen partial pressure in the vacuum chamber as constant as possible during film formation. Since the oxygen partial pressure can be maintained at a constant level, it is preferable to control the pressure in the vacuum chamber 1 by adjusting the exhaust speed of the vacuum exhaust device 17 installed in the vacuum chamber 1.

In consideration of the fact that the film stress increases as the thickness of the film increases, the manufacturing cost, and the light transmittance, the thickness of the ITO transparent conductive film is preferably 300 nm or less, more preferably 200 nm or less.

The ITO transparent conductive film according to one embodiment of the present invention may have an arithmetic mean roughness exceeding within 2 nm of the arithmetic mean roughness of the substrate before formation of the ITO transparent conductive film. In contrast, an ITO transparent conductive film obtained by sputtering may have an arithmetic mean roughness that exceeds the arithmetic mean roughness of the substrate prior to ITO transparent conductive film formation to about 5 nm or more. Therefore, the ITO transparent conductive film according to one embodiment of the present invention is excellent in surface smoothness.

Therefore, in order to smooth the surface, a process of polishing the surface of the ITO transparent conductive film may be unnecessary. The substrate having the ITO transparent conductive film according to one embodiment of the present invention can be preferably used for a device requiring softness (for example, an organic EL device).

FIG. 2 shows an ion plating apparatus similar to the apparatus of FIG. 1. The device of FIG. 2 is distinguished from the device of FIG. 1 in that it does not have a substrate holder and heats the substrate at another location. In the apparatus of FIG. 2, the substrate 25 heated by the heater 11 is transferred to the vacuum chamber 1 by a transfer tray (not shown). Since the substrate 25 is transferred above the ITO source of the crucible 3, an ITO transparent conductive film is formed on the substrate 25 in a state where the film forming conditions become stable.

Hereinafter, the present invention will be described in detail with reference to the following examples.

Example 1

A transparent conductive film was formed on the substrate in the following manner using the apparatus of FIG. 1.

The carbon crucible 3 was charged with an ITO source, i.e., an ITO mass (Sn content in oxidized form: 5% by weight) manufactured by Kojundo Chemical Lab, Co., Ltd. The filled crucible 3 is placed in a predetermined place in the vacuum chamber 1.

A polyethylene terephthalate (PET) film (width: 20 cm, thickness: 100 μm; trademark: polyester film E5101 (TOYOBO., LTD.)) Was prepared as the substrate 25, washed, and mounted on the substrate holder 4 It was.

Thereafter, the vacuum chamber 1 was evacuated using the vacuum evacuation apparatus 17 for about 2 hours until the pressure in the vacuum chamber 1 reached 2.0 × 10 ⁻⁴ Pa. During this evacuation operation, the PET film was heated to 100 ° C.

Argon gas was introduced into the voltage gradient plasma gun 2 at 20 sccm flow rate, and oxygen gas 15 was introduced into the vacuum chamber 1 at 20 sccm flow rate. Thereafter, power was gradually applied until the output of the voltage gradient plasma gun 2 reached 2.5 kW. The plasma beam 12 is generated from the voltage gradient plasma gun 2, and the generated plasma beam 12 is concentrated on the ITO source 19 to heat and evaporate the ITO source 19. A voltage gradient cavity cathode plasma gun was used as the voltage gradient plasma gun 2.

At the same time, the exhaust speed of the vacuum exhaust device 17 was adjusted by the conductance valve 16 to adjust the pressure in the vacuum chamber 1 to 0.1 Pa.

After discharge, the pressure and ITO source evaporation were stabilized and the shutter was opened for about 60 seconds, thereby forming an ITO film on the PET film.

As a result, an ITO film (thickness: 150 nm) was formed at a very high film formation rate of 2.5 nm / s. The amount of heat applied to the substrate was 3.3 J / cm ² min. The obtained ITO transparent conductive film showed a sheet resistance of 10 Ω / □ and a very low specific resistance of 1.5 × 10 ⁻⁴ Ω.cm.

The obtained substrate with ITO was subjected to the cross-sectional cut adhesion test of Japanese Industrial Standard (JIS) R 3220. In this test, the ITO film did not peel off on the substrate. Therefore, it was judged that adhesiveness was excellent.

The PET film was not wound due to the formation of ITO film thereon. ITO films had little internal stress. The film was transparent and its transmittance was measured at 83% in light of a wavelength of 550 nm. The arithmetic mean roughness Ra of the ITO film was greater by 0.5 nm compared to the substrate before ITO formation. Thus, the ITO film was judged to have a very smooth surface.

Example 2

A transparent conductive film was formed on the substrate in the following manner using the apparatus of FIG.

As in Example 1, the carbon crucible 3 was charged with an ITO source 19, i.e., an ITO mass (Sn content in oxidized form: 5% by weight) manufactured by Chemical Lab, Co., Ltd. It was. The filled crucible 3 is placed in a predetermined place in the vacuum chamber 1.

As a substrate 25, a PET film (width: 20 cm, thickness: 100 mu m; trademark: polyester film E5101 (TOYOBO., LTD)) was prepared, washed, and placed on a transfer tray (not shown). The PET film was heated to a temperature of 100 ° C. ITO source 19 was evaporated under the same conditions as in Example 1. After discharge, the pressure and ITO source evaporation were stabilized and the ITO film was formed on the PET film while the PET film was transferred at a rate of 3.3 mm / s.

As a result, the obtained ITO film had a thickness of 150 nm. The amount of heat applied to the substrate was 3.3 J / cm ² min. The obtained ITO transparent conductive film exhibited sheet resistance of 11 Ω / □ and very low specific resistance of 1.7 × 10 ⁻⁴ Ω.cm.

The obtained substrate with ITO film was subjected to the cross-sectional cut adhesion test of JIS R 3220. In this test, the ITO film did not peel off on the substrate. Therefore, it was judged that adhesiveness was excellent.

The PET film was not wound due to the formation of ITO film thereon. ITO films had little internal stress. The film was transparent and its transmittance was measured at 83% in light of a wavelength of 550 nm. The arithmetic mean roughness (Ra) of the ITO film was larger by 0.7 nm compared to the substrate before ITO formation. Thus, the ITO film was judged to have a very smooth surface.

Comparative Example 1

An ITO film was formed in the same manner as in Example 1 except that an electric power of 7.5 kW was applied to the voltage gradient plasma gun 2 and the shutter was opened for 30 seconds to form an ITO film. The obtained ITO film had a thickness of 150 nm. The amount of heat applied to the substrate was 10.2 J / cm ² .min. The obtained ITO film contained cracks on the entire surface. That is, the obtained ITO film was broken and did not have conductivity. Therefore, the surface resistance was infinite.

Comparative Example 2

In the same manner as in Example 1 except that the substrate 25 was heated to 50 ° C., an electric power of 7.5 kW was applied to the voltage gradient plasma gun 2, and the shutter was opened for 30 seconds to form an ITO film. An ITO film was formed.

The obtained ITO film had a thickness of 150 nm. The amount of heat applied to the substrate was 10.2 J / cm ² .min. The sheet resistance changed significantly with different measurement positions on the ITO substrate. Therefore, the ITO film was judged to be inferior.

Comparative Example 3

An ITO film was formed in the same manner as in Example 1 except that the pressure in the vacuum chamber 1 was adjusted to 0.4 Pa by adjusting the exhaust speed of the vacuum exhaust device 17. The obtained ITO film had a thickness of 145 nm. The amount of heat applied to the substrate was 3.3 J / cm ² min.

The obtained ITO transparent conductive film showed a sheet resistance of 24 Ω / □ and a specific resistance of 3.5 × 10 ⁻⁴ Ω.cm. The specific resistance was higher than that in Example 1.

The transmittance of the ITO film in light at a wavelength of 550 nm was measured to be 82%. The arithmetic mean roughness (Ra) of the ITO film was larger by 1.0 nm compared to the substrate before ITO formation.

Comparative Example 4

An ITO film was formed in the same manner as in Example 1 except that the pressure in the vacuum chamber 1 was adjusted to 0.1 Pa by adjusting the amount of argon gas introduced into the vacuum chamber 1.

An ITO film (thickness: 150 nm) was formed at 1.5 nm / s, which is a very fast film formation rate. However, the obtained ITO transparent conductive film showed a very high sheet resistance of 180 Ω / □ and a very high specific resistance of 2.7 × 10 ⁻³ Ω.cm. The transmitted light was brown.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications and changes can be made within the scope of the claims and the detailed description of the invention and the accompanying drawings. Naturally, it belongs to the range of.

 As described above, the ITO transparent conductive film produced by the ITO transparent conductive film production method of the present invention was formed at a very high film formation rate, very low sheet resistance and specific resistance, and excellent adhesion. In addition, the ITO transparent conductive film of the present invention is not wound around the substrate due to the formation of the ITO film, has no internal stress, transparent, and excellent light transmittance and surface smoothness.

Claims (5)

In the method of forming an ITO transparent conductive film on a substrate containing an organic polymer using an ion plating apparatus, (a) generating a plasma beam from the voltage gradient plasma gun into the vacuum chamber; (b) irradiating the ITO source with the plasma beam to heat and evaporate the ITO source; (c) ionizing the evaporated ITO source in a plasma atmosphere; And (d) depositing the ionized ITO source onto the substrate to form an ITO transparent conductive film on the substrate; Including, Adjust the temperature of the substrate to 80-145 ° C. for at least step (d), A method of forming an ITO transparent conductive film, wherein the radiant heat incident on the substrate from at least one step (d) is adjusted to 1.5 to 10.0 J / cm ² .min per unit time and unit unit area. The method of claim 1, And adjusting the pressure in the vacuum chamber to 0.05 to 0.3 Pa by controlling the exhaust of the exhaust device installed in the vacuum chamber. The method according to claim 1 or 2, Preheat the substrate before step (a), During preheating of the substrate, the actual temperature of the substrate is measured by a first thermometer temporarily attached to the substrate, At the same time as measuring the actual temperature, the approximate temperature of the substrate is again measured by a second thermometer provided in the vacuum chamber and disposed in proximity to the substrate, Calculate a measurement curve from the actual temperature and the approximate temperature to provide the actual temperature from the approximate temperature, During the steps (a) to (d), forming the ITO transparent conductive film measuring the approximate temperature with the second thermometer, determining the actual temperature as the measurement curve, and adjusting the actual temperature to 80 to 145 ° C. Way. A substrate having an ITO transparent conductive film prepared according to the method of claim 1, wherein Wherein the ITO transparent conductive film comprises indium oxide doped with 5-10 wt% tin in the form of oxide, wherein the ITO transparent conductive film has a resistivity of 1.2 × 10 ⁻⁴ to 3.0 × 10 ⁻⁴ Ω.cm A substrate having an ITO transparent conductive film. The method of claim 4, wherein And the ITO transparent conductive film has the ITO transparent conductive film having an arithmetic mean roughness increased to 2 nm or less than before forming the ITO transparent conductive film.

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