WO2009104579A1 - Plasma discharge device and thin film laminate - Google Patents

Abstract

Provided are a plasma discharge device that forms thin films of excellent film thickness uniformity and thin film layered products. The plasma discharge device is characterized by the fact that in a plasma discharge device having opposing electrodes consisting of a pair of rotating roll electrodes, a plasma discharge space wherein voltage is applied between the opposing electrodes to generate a plasma discharge, a substrate that passes through the plasma discharge space while being held by said opposing electrodes that consist of roll electrodes, and a process gas supply means that supplies process gas into said plasma discharge space, said process gas is composed of a discharge gas and a thin film-forming gas, said discharge gas contains at least 90 vol% or more of nitrogen gas, and the ratio of the diameters of the above pair of roll electrodes that constitute said opposing electrodes is 1.00:0.55 to 1.00:0.95.

Description

Plasma discharge treatment apparatus and thin film laminate

The present invention relates to a novel plasma discharge treatment apparatus and a thin film laminate for forming a homogeneous functional thin film on a substrate.

In recent years, various products such as LSIs, semiconductors, display devices, magnetic recording devices, photoelectric conversion devices, etc. have many materials in which high-functional thin films such as electrode films, dielectric protective films, and semiconductor films are provided on a substrate. It is used.

Such high-functional thin films can be obtained by wet deposition methods such as coating methods, or plasma using vacuum deposition, sputtering, ion beam, ion plating, or glow discharge under reduced pressure. -Chemical vapor deposit (CVD) method has been used. However, each of these methods comprises a vacuum processing means, and the processing system needs to be considerably depressurized. Therefore, the film forming apparatus to be used is not a large-scale processing chamber or a large vacuum pump. It becomes a device or a device unit, and requires complicated work under a high pressure reduction. Furthermore, on the performance of these devices and device units, the roll diameter, width, etc. of the substrate wound in a roll shape There are size, capacity of raw materials for thin film formation, and various other limitations.

For example, the atmospheric pressure plasma discharge treatment thin film formation method can achieve a higher performance thin film than the wet film formation method, and the productivity compared to the dry film formation method using a vacuum. Is being devised and put to practical use because of its high cost. Since the atmospheric pressure plasma discharge treatment method does not need to be evacuated, it has an advantage that continuous film formation is possible as in the coating method.

As a device used for continuous surface treatment or continuous film formation using these atmospheric pressure plasmas, a pair of parallel plate electrodes with a smooth curved edge is used as a discharge plasma treatment electrode to prevent tip discharge. ing.

Such parallel plate electrodes are easy to manufacture and set the distance between the electrodes, and the electrode area can be widened, so that the film to be processed transferred between the electrodes is sequentially processed in the transfer direction, and the film formation speed is increased. In addition, the plasma processing gas density can be increased as compared with the above-described low-pressure plasma, and the processing efficiency is excellent. However, the cost of equipment such as electrodes is high, and the key to practical use is to reduce the equipment cost or to reduce the cost by increasing the processing capacity. In order to increase the processing capacity, it is conceivable to increase the energy by increasing the plasma density or increasing the electric field strength. However, when the electric field strength is increased, there is a risk of concentrated discharge of a large current due to the arc.

Further, since the electrode is a fixed electrode, it is constantly exposed to the flow of a mixed gas for film formation, and plasma discharge is continued. Therefore, the surface of the electrode is gradually contaminated, and finally the discharge state. The film has a problem in that the film formed and the performance of the treated surface are varied, and in the case of remarks, defects such as streaks and unevenness are clearly recognized.

In order to prevent the electrodes from being contaminated, there has been proposed a method in which a mixed gas is supplied between discharge plasma processing electrodes in which the electrodes are in a roll shape to perform discharge plasma processing (for example, see Patent Documents 1 to 3).

However, in each of the methods described in these patent documents, a pair of roll electrodes that form a discharge space uses roll electrodes having the same diameter (that is, the same circumference), but each roll electrode is installed. When the roll electrodes are rotated, fluctuations in the distance between the electrodes are caused by the centering error due to the error of the central axis at the time, the distortion at the circumferential portion when the roll electrodes are processed, and the like. In particular, when the displacements of the opposing roll electrodes are synchronized, strong film thickness irregularities appear periodically. Due to such a variation in the distance between electrodes (a variation in the discharge distance), a variation in the discharge intensity is caused, resulting in a difference in the physical characteristics and the formed film thickness of the thin film formed on the substrate. In particular, when the thin film is an antireflection layer formed by laminating thin films with different refractive indexes while precisely controlling them, the reflectance and color tone are greatly affected by the refractive index of each layer and the film thickness to be formed. Therefore, it becomes an important factor to suppress the discharge distance fluctuation at the time of thin film formation.
JP 2001-279457 A JP 2003-93870 A JP 2004-189958 A

The present invention has been made in view of the above problems, and an object of the present invention is to provide a plasma discharge treatment apparatus and a thin film laminate that form a thin film with excellent film thickness uniformity.

The above object of the present invention is achieved by the following configuration.

1. A counter electrode composed of a pair of rotating roll electrodes, a plasma discharge space that generates a plasma discharge by applying a voltage between the counter electrodes, and a base material that passes through the plasma discharge space while being held by the counter electrode composed of the roll electrode And a processing gas supply means for supplying a processing gas to the plasma discharge space, wherein the processing gas includes a discharge gas and a thin film forming gas, and the discharge gas contains at least 90% by volume of nitrogen gas. A plasma discharge treatment apparatus characterized in that the diameter ratio of a pair of roll electrodes that are contained above and constitute the counter electrode is 1.00: 0.55 to 1.00: 0.95.

2. 2. The plasma discharge treatment apparatus according to 1 above, wherein a functional thin film is formed on the substrate.

3. 3. The plasma discharge processing apparatus according to claim 1 or 2, wherein the processing gas supply means supplies a processing gas having an atmospheric pressure or a pressure in the vicinity thereof between the counter electrodes.

4. 4. The plasma discharge processing apparatus according to any one of claims 1 to 3, wherein the plasma discharge is a method of superposing a first high-frequency electric field and a second high-frequency electric field to cause plasma discharge.

5. The plasma discharge treatment apparatus according to any one of 1 to 4, wherein the substrate is folded and conveyed to form a functional thin film on the substrate.

6. 6. The plasma discharge treatment apparatus according to any one of 1 to 5, wherein the base material is continuously transported by a loop transport method to form a functional thin film on the base material.

7. 7. A thin film laminate in which a functional thin film is formed on the surface of a substrate using the plasma discharge treatment apparatus according to any one of 1 to 6 above.

8. 8. The thin film laminate according to 7, wherein the functional thin film is an antireflection film.

According to the present invention, it was possible to provide a plasma discharge treatment apparatus and a thin film laminate that form a thin film with excellent film thickness uniformity.

It is the schematic which shows an example of the plasma discharge processing apparatus which has a pair of conventional roll electrode of the same diameter. It is a schematic diagram which shows the fluctuation | variation of the discharge distance L in the discharge space comprised from the roll electrode pair of the same diameter. It is a schematic diagram which shows an example of the plasma discharge processing apparatus of this invention which has a roll electrode pair of a different diameter. It is a schematic diagram which shows the fluctuation | variation of the discharge distance L in the discharge space comprised from a roll electrode pair of a different diameter. It is a schematic diagram which shows an example of the plasma discharge treatment apparatus which has a roll electrode pair of a different diameter and performs thin film formation by carrying continuously. It is a schematic diagram which shows an example of the plasma discharge processing apparatus which has a roll electrode pair of a different diameter, conveys continuously, and forms thin film simultaneously on a different base material. It is a schematic diagram which shows an example of the plasma discharge processing apparatus using a 2 frequency roll electrode by an example of the plasma discharge processing apparatus (folding conveyance system) of this invention. It is a schematic diagram which shows an example of the plasma discharge processing apparatus using a 2 frequency roll electrode by an example of the plasma discharge processing apparatus (loop conveyance system) of this invention. It is a schematic diagram which shows an example of the gas supply means applicable to the plasma discharge processing apparatus of this invention. It is a schematic diagram which shows another example of the gas supply means applicable to the plasma discharge processing apparatus of this invention. It is a schematic diagram which shows another example of the gas supply means applicable to the plasma discharge processing apparatus of this invention. It is a perspective view which shows an example of the roll electrode applicable to this invention.

Explanation of symbols

1 Atmospheric pressure plasma discharge device 10, 10 ', 10A, 10B, 10C Roll electrode 11A, 11B, 11C, 11D Folding roll (U-turn roll)
11E, 11F Support roll 20, 21 Guide roll 200a, 200A Conductive base material 200b Ceramic coating dielectric 200B Lining dielectric 30 Processing gas supply unit 31 Nip roller 32 Blade 40 Discharge port 80 Power supply 801 First power supply 802 Second power supply 81, 82, 811, 812, 821, 822 Voltage supply means 831 1st filter 832 2nd filter 100 Discharge section A1, B1, C1 Rotation cycle of roll electrode CG Auxiliary gas d1, d2 Diameter of roll electrode F, F1, F2 Base material G Reaction gas G 'Gas after treatment L Discharge distance

Hereinafter, the best mode for carrying out the present invention will be described in detail.

As a result of intensive studies in view of the above problems, the present inventor has found that a counter electrode composed of a pair of rotating roll electrodes, a plasma discharge space for generating a plasma discharge by applying a voltage between the counter electrodes, and the roll electrode A plasma discharge processing apparatus having a base material that passes through a plasma discharge space while being held by a counter electrode, and a processing gas supply means for supplying a processing gas to the plasma discharge space. The discharge gas contains at least 90% by volume of nitrogen gas, and the diameter ratio of a pair of roll electrodes constituting the counter electrode is 1.00: 0.55 to 1.00: 0. It was found that a plasma discharge processing apparatus capable of forming a thin film with excellent film thickness uniformity can be realized by the plasma discharge processing apparatus characterized by being 95. Tsu was is up.

Hereinafter, the details of the plasma discharge treatment apparatus and the thin film laminate of the present invention will be described.

[Plasma discharge treatment equipment]
The plasma discharge treatment apparatus according to the present invention is characterized in that the diameter ratio of a pair of roll electrodes constituting a counter electrode is 1.00: 0.55 to 1.00: 0.95. Excellent effect on surface treatment, for example, highly functional thin films with high homogeneity using discharge gas and source gas (for example, antireflection film, gas barrier film, hard coat film, antiglare film) Film, antifouling film, conductive film, etc.), surface modification of substrates and functional thin films, for example, oxidation treatment or reduction treatment after functional thin film is formed, or hydrophilic It can be widely applied to the surface treatment field such as chemical treatment.

Hereinafter, the plasma discharge treatment apparatus of the present invention applicable to a wide range of fields will be described by taking as an example a method for forming a functional thin film, but the field of application of the present invention is limited only to these exemplified film forming methods. is not.

The plasma discharge treatment apparatus of the present invention and the plasma discharge treatment apparatus of the comparative example will be described with reference to the drawings.

FIG. 1 is an example of a conventional plasma discharge treatment apparatus, schematically showing a plasma discharge treatment apparatus used for forming a thin film by reciprocating a substrate using roll electrodes having the same diameter. This plasma discharge treatment apparatus 1 has a pair of roll electrodes 10A and 10B having the same diameter, and a power supply 80 capable of applying a voltage for plasma discharge to these roll electrodes 10A and 10B is a voltage supply means. 81 and 82 are connected. The roll electrodes 10 </ b> A and 10 </ b> B having the same roll diameter are rotary electrodes that can be rotated while winding the base material F. The discharge unit (also referred to as discharge space) 100 is maintained at, for example, atmospheric pressure or a pressure in the vicinity thereof, the process gas G is supplied from the process gas supply unit 30, and plasma discharge is performed in the discharge unit 100 having the discharge space gap L. Is done.

The base material F supplied from the pre-process or the former winding roll is brought into close contact with the roll electrode 10A by the guide roll 20 and rotated and transferred in synchronization, and is subjected to plasma discharge treatment by the processing gas G in the discharge section 100.

The processing gas supply means 30 is preferably in the form of a slit that is the same as or slightly wider than the width of the base material, or pipe-shaped outlets are arranged side by side so as to be equivalent to the width of the base material. The processing gas G may be introduced into the discharge unit 100 at a uniform flow rate or flow rate throughout the width direction. The substrate F once processed passes through folding rolls (also referred to as U-turn rolls) 11A, 11B, 11C, and 11D, is transferred in the reverse direction, is held by the roll electrode 10B, and is subjected to plasma discharge treatment again in the discharge unit 100. It is wound up via the guide roll 21 or transferred to the next step (none of which is shown). The treated gas G ′ is exhausted from the exhaust port 40. The exhaust flow rate from the exhaust port 40 is preferably equal to or slightly higher than the flow rate from the processing gas supply means 30. The side surfaces of the roll electrodes 10A and 10B of the discharge unit 100 may be shielded, or the entire apparatus may be surrounded and filled with a rare gas or a processing gas.

When the pair of roll electrodes 10A and 10B constituting the discharge unit 100 as shown in FIG. 1 have the same diameter, a roll circumference distortion due to deviation from a perfect circle at the time of producing each roll electrode, or a predetermined discharge space When the roll electrodes are installed at positions facing each other to form, due to the eccentricity of the center of each roll electrode, the discharge distance L in the discharge space varies due to the rotation of the roll electrode, When roll electrodes having the same diameter (same circumference) are used, the eccentric portions of the respective roll electrodes are always constant, so that the deviations of the respective roll electrodes are synchronized, and there is a large variation in the discharge distance L. The result will appear periodically.

FIG. 2 is a schematic diagram showing the variation of the discharge distance L in the discharge space composed of roll electrodes having the same diameter.

2, the solid line represents the roundness pattern of the roll electrode 10A in FIG. 1, and the rotation period is A1. A broken line represents the roundness pattern of the roll electrode 10B at a position facing the roll electrode 10A, and the rotation period is B1. Here, the rotation period A1 and the rotation period B1 are exactly the same.

In the discharge space 100 formed by each roll electrode having such roundness characteristics, when the maximum diameter part or the minimum diameter part of each roll electrode is synchronized, the discharge distance L is as shown by a dashed line in FIG. By exhibiting a discharge distance pattern in which a simple discharge treatment changes greatly from the minimum distance to the maximum distance as the roll electrode rotates, the uniformity and characteristics of the thin film formed on the substrate are greatly impaired due to the fluctuation of the discharge distance. Result.

In response to the above problem, in the plasma discharge processing apparatus of the present invention, the diameter ratio of the pair of roll electrodes forming the discharge space is set to a configuration of 1.00: 0.55 to 1.00: 0.95. It is a feature.

FIG. 3 is a view schematically showing a plasma discharge treatment apparatus of the present invention having a pair of roll electrodes having different diameters.

The basic configuration of the plasma discharge processing apparatus 1 shown in FIG. 3 is almost the same as the configuration described with reference to FIG. 1, but the diameter ratio of the roll electrodes that constitute the discharge space is 1.00: 0.55. 1.00: 0.95, and when the diameter of one roll electrode 10A is d1 and the diameter of the other roll electrode 10C is d2, d1> d2 Yes.

In the present invention, the diameter ratio between the roll electrode 10A and the roll electrode 10C is 1.00: 0.55 to 1.00: 0.95, preferably d2 / d1 is 0.00. It is in the range of 75 to 0.90.

In the present invention, by adopting the configuration of the roll electrode defined in the present invention, the fluctuation range of the discharge distance L due to the distortion of the roll circumference at the time of production of each roll electrode or the eccentricity at the time of roll electrode installation is suppressed. Thus, a thin film laminate having excellent thin film uniformity can be obtained.

In the present invention, it is preferable that the thin film formed on the substrate using the plasma discharge treatment apparatus of the present invention is a functional thin film. The functional thin film as used in the present invention refers to a film having each function such as an antireflection film, a gas barrier film, an antistatic film, an antifouling film, an antiglare film, a hard coat film, etc. It is preferable that the conductive thin film is an antireflection film from the viewpoint that the objective effect of the present invention can be exhibited. The details of the antireflection film will be described later.

FIG. 4 is a schematic diagram showing the variation of the discharge distance L in the discharge space composed of roll electrodes having different diameters.

4, the solid line represents the roundness pattern of the roll electrode 10A in FIG. 3, and the rotation period is A1. A broken line represents the roundness pattern of the roll electrode 10C at a position facing the roll electrode 10A, and the rotation period is C1. Here, unlike the rotation cycle A1 and the rotation cycle B1, there is a feature that there is a phase shift.

In the discharge space 100 formed by each roll electrode having such roundness characteristics, the probability that the maximum diameter part or the minimum diameter part of each roll electrode is synchronized is the same as the roll electrode of the same diameter shown in FIG. As a result, the discharge distance L is suppressed by showing the discharge distance pattern in which the fluctuation of the discharge distance L is suppressed as the roll electrode rotates, as indicated by the one-dot broken line in FIG. This improves the uniformity and characteristics of the thin film formed on the substrate.

In the plasma discharge processing apparatus shown in FIG. 3, the base material F processed in the discharge unit 100 is transferred in the reverse direction through the folding rolls 11 </ b> A, 11 </ b> B, 11 </ b> C and 11 </ b> D, and held by the roll electrode 10 </ b> C. In FIG. 2, after the second plasma discharge treatment, the sheet is wound up through the guide roll 21 or is transferred to the next process (none of which is shown). As a preferred embodiment, a method in which an endless base material is held between the folding rolls 11A, 11B, 11C, and 11D and the functional thin film is formed while being continuously conveyed by a loop conveying method.

FIG. 5 is a diagram schematically showing a plasma discharge treatment apparatus having roll electrode pairs with different diameters and performing thin film formation by continuous conveyance in a loop manner.

In the plasma discharge treatment apparatus 1, the endless base material F held by the folding rolls 11A, 11B, 11C, and 11D is continuously conveyed with the thin film forming surface inside. The discharge unit 100 is designated by disposing the roll electrode 10A having a diameter d1 and the roll electrode 10C having a diameter d2 facing each other. At this time, d1> d2.

A power supply 80 capable of applying a voltage for plasma discharge is connected to each of the roll electrodes 10A and 10C via voltage supply means 81 and 82. The roll electrodes 10 </ b> A and 10 </ b> C having different diameters are rotating electrodes that can be rotated while winding the base material F, and the discharge unit 100 is maintained at, for example, atmospheric pressure or a pressure in the vicinity thereof, and the processing gas supply unit 30. Then, the processing gas G is supplied, plasma discharge is performed in the discharge section 100 having the discharge space gap L, and the processed gas G ′ is exhausted from the exhaust port 40.

In the present invention, an example of the thin film forming method using a single base material is shown in FIGS. 3 and 5 as the base material transport system. However, as shown in FIG. On the other hand, you may apply to the method (it is also called an independent conveyance system) which forms a thin film simultaneously with respect to the different base materials F1 and F2 which carry out independent continuous conveyance through the corresponding support rolls 11E and 11F, respectively.

Among the substrate transport methods described above, the plasma discharge processing apparatus provided with the folding transport mechanism as shown in FIG. 3 or the loop transport mechanism as shown in FIG. 5 is more than the independent transport method shown in FIG. Since the base material passes through different roll electrode surfaces, discharge unevenness of each roll electrode can be canceled, and this is preferable from the viewpoint of forming a more uniform functional thin film.

】 Regarding the reason, its function is not clear at present, but it is estimated as follows.

When a counter roll electrode having a diameter ratio specified by the present invention of 1.00: 0.55 to 1.00: 0.95 is used, the amount of air entrained varies depending on the roll diameter or roll rotation speed of the counter roll electrode. May occur. As a result, weak discharge unevenness and thin film unevenness may be caused. However, such a folded transfer method or loop transfer method can particularly compensate for the discharge unevenness caused by the inflow of entrained air, and is more uniform. It is preferable from the viewpoint that a high thin film can be formed.

That is, when the discharge space is formed using the opposing roll electrodes, in the independent transfer type plasma discharge processing apparatus as shown in FIG. 6, the processing gas supply unit 30 for supplying the discharge gas and the raw material gas and the roll electrode 10A. Introducing air from the outside of the discharge space 100 (also referred to as entrained air) as the substrate is conveyed by the rotation of each roll electrode through the gap between the discharge gas 100 and the gap between the processing gas supply unit 30 and the roll electrode 10C having a smaller diameter. As a result, the processing gas supplied to the surface of each roll electrode naturally forms a mixture with the entrained air, thereby causing unevenness in the concentration of the processing gas and the width of the roll electrode. It becomes a factor which produces the thin film nonuniformity in a hand direction. The processing gas concentration unevenness pattern in the width direction of the roll electrode becomes an almost constant unevenness pattern when film formation is performed under a certain condition. Is a factor that causes a slightly strong density unevenness at a certain position.

On the other hand, in the plasma discharge processing apparatus provided with the folded transfer mechanism or the loop transfer mechanism that passes through each of the counter electrodes, the discharge gas concentration unevenness occurs due to the carry-in air as described above. By passing through the roll electrodes with different concentration patterns, the non-uniformity in discharge gas concentration due to the specific roll electrode is not emphasized, and the non-uniformity in discharge gas concentration is compensated for, thereby providing a more homogeneous functional film. It is preferable from the viewpoint of formation.

In the plasma discharge processing apparatus of the present invention, the processing gas supply means supplies a processing gas having an atmospheric pressure or a pressure near it between the opposing electrodes, or the discharge space is formed under an atmospheric pressure or a pressure near it. It is preferable.

Compared with the plasma CVD method under vacuum, the plasma discharge processing apparatus of the present invention performed under atmospheric pressure or a pressure close to it does not need to be reduced in pressure, has high productivity, and has a high plasma density. For this reason, the film forming speed is high, and further, under a high pressure condition under atmospheric pressure as compared with the conditions of a normal CVD method, the mean free path of gas is very short, so that a very homogeneous film can be obtained.

In the present invention, the vicinity of atmospheric pressure represents a pressure of 20 kPa to 110 kPa, but 93 kPa to 104 kPa is preferable in order to obtain a good effect described in the present invention.

3, 5, and 6, as a method of applying to the roll electrode, a plasma discharge processing apparatus having a power source 80 that can apply a voltage for a single plasma discharge and a high frequency power source in one frequency band will be described. However, in the plasma discharge processing apparatus of the present invention, a power source having a different frequency is installed on each roll electrode, and the first high-frequency electric field and the second high-frequency electric field are superimposed to cause plasma discharge. This is one of the more preferred embodiments. In the present invention, hereinafter, the former method including the power source 80 capable of applying a voltage for a single plasma discharge and having a high frequency power source in one frequency band is referred to as an application method A. Further, the latter method in which a power source having a different frequency is installed in each roll electrode, the first high-frequency electric field and the second high-frequency electric field are superimposed, and plasma discharge is referred to as an application method B.

In the application method B in which the first high-frequency electric field and the second high-frequency electric field are superimposed and plasma discharge is performed in the present invention, a high-frequency voltage is applied to the discharge part between the first roll electrode and the second roll electrode facing each other. The high-frequency voltage has at least a component obtained by superimposing the voltage component of the first frequency ω _{1 and} the voltage component of the second frequency ω ₂ higher than the first frequency ω ₁ . High frequency refers to one having a frequency of at least 0.5 kHz.

The high frequency voltage is a component obtained by superimposing the voltage component of the first frequency ω _{1 and} the voltage component of the second frequency ω ₂ higher than the first frequency ω ₁ , and the waveform thereof is on the sine wave of the frequency ω _1. In addition, the sine wave of ω ₁ on which the sine wave of higher frequency ω ₂ is superimposed becomes a waveform that is jagged.

FIG. 7 shows an example of the plasma discharge processing apparatus of the present invention, in which plasma discharge processing is performed by reciprocating a substrate using a roll electrode of an application method B in which a first high-frequency electric field and a second high-frequency electric field are superimposed. It is the figure which showed the apparatus typically. This apparatus has a pair of roll electrodes 10A (first electrodes) and roll electrodes 10C (second electrodes) having different diameters. A first power supply 801 capable of applying a high-frequency voltage V1 having a frequency ω1 for plasma discharge is connected to the roll electrode 10A via a voltage supply unit 811. A second power source 802 capable of applying a high-frequency voltage V2 having a frequency ω2 for plasma discharge is connected to the roll electrode 10C via a voltage supply unit 812. The first power source 801 preferably has the ability to apply a higher frequency voltage (V1> V2) than the second power source 802, and the first frequency ω1 of the first power source 801 and the second frequency of the second power source 802 are the same. The frequency ω2 is preferably ω1 <ω2. A first filter 831 is installed between the roll electrode 10A and the first power source 801 so that the current from the first power source 801 flows toward the roll electrode 10A, and the current I1 from the first power source 801 is It is designed so that the current I2 from the second power source 802 does not easily pass to the ground side and easily passes to the ground side. A second filter 832 is installed between the roll electrode 10B and the second power source 802 so that the current from the second power source 802 flows toward the roll electrode 10C. It is designed to make it difficult for I2 to pass to the ground side and to easily pass the current I1 from the first power source 801 to the ground side.

As another discharge condition in the present invention, a high frequency voltage is applied between the opposed first electrode and second electrode, and the high frequency voltage causes the first high frequency voltage V1 and the second high frequency voltage V2 to be applied. When the discharge start voltage is IV, V1 ≧ IV> V2 or V1> IV ≧ V2 is preferably satisfied, and V1> IV> V2 is more preferable.

Here, the frequency of the first power source is preferably 200 kHz or less. The electric field waveform may be a sine wave or a pulse. The lower limit is preferably about 1 kHz.

On the other hand, the frequency of the second power source is preferably 800 kHz or more.

The higher the frequency of the second power source, the higher the plasma density, and a dense and good quality thin film can be obtained. The upper limit is preferably about 200 MHz.

In the present invention, the power applied between the electrodes facing each other is such that power (power density) of 1 W / cm ² or more is supplied to the second electrode (second high-frequency electric field) to excite the discharge gas to generate plasma. The energy is applied to the thin film forming gas to form a thin film. The upper limit value of the power supplied to the second electrode is preferably 50 W / cm ² , more preferably 20 W / cm ² . The lower limit is preferably 1.2 W / cm ² . In addition, discharge area (cm < ² >) points out the area of the range which discharge occurs in an electrode.

Further, by supplying power (output density) of 1 W / cm ² or more to the first electrode (first high frequency electric field), the output density is improved while maintaining the uniformity of the second high frequency electric field. be able to. Thereby, the further uniform high-density plasma can be produced | generated, and the improvement of the film forming speed and the improvement of film quality can be made compatible. Preferably it is 5 W / cm ² or more. The upper limit value of the power supplied to the first electrode is preferably 50 W / cm ² .

FIG. 8 shows a configuration in which a dual frequency system is applied as an applied power source to the plasma discharge processing apparatus having the roll electrode pairs having different diameters shown in FIG. The application method is the same mechanism as described in FIG.

As the first power source 2 (high frequency power source),
Applied power symbol Manufacturer Frequency Product name A1 Shinko Electric 3kHz SPG3-4500
A2 Shinko Electric Co., Ltd. 5kHz SPG5-4500
A3 Kasuga Electric 15kHz AGI-023
A4 Shinko Electric 50kHz SPG50-4500
A5 HEIDEN Laboratory 100kHz * PHF-6k
A6 Pearl Industry 200kHz CF-2000-200k
And the like, and any of them can be used.

As the second power source (high frequency power source),
Applied power symbol Manufacturer Frequency Product name B1 Pearl Industry 800kHz CF-2000-800k
B2 Pearl Industry 2MHz CF-2000-2M
B3 Pearl Industry 13.56MHz CF-5000-13M
B4 Pearl Industry 27MHz CF-2000-27M
B5 Pearl Industry 150MHz CF-2000-150M
B6 Pearl Industry 20-99.9 MHz RP-2000-20 / 100M and other commercially available products can be mentioned, and any of them can be used.

Of the above power sources, * indicates a HEIDEN Laboratory impulse high-frequency power source (100 kHz in continuous mode). Other than that, it is a high-frequency power source that can apply only a continuous sine wave.

[Gas supply means]
In the plasma discharge treatment apparatus of the present invention, from the viewpoint of stably forming a homogeneous functional thin film, it is a more preferable aspect to have various gas supply means shown below in the discharge part.

FIG. 9 is a schematic view showing an example of gas supply means applicable to the plasma discharge treatment apparatus of the present invention.

In FIG. 7, the processing gas G is blown out in the direction of the gap between the roll electrodes 10A and 10C. However, if the gap between the roll electrodes is narrow at that time, the entire amount of the blown processing gas cannot always pass through the gap. A part of the gas leaks from the gap between the processing gas supply means 30 and the roll electrode and blows out to the outside, so that an extra processing gas is required and the processing chamber is filled. Also, depending on the type of processing gas, there is a concern that it may adversely affect the human body.

In the form of the plasma discharge processing apparatus of the present invention, in order to solve the above problem, as a means for shutting out the leaked processing gas as shown in FIG. 9, an auxiliary gas CG outlet is provided in the processing gas supply means 30. It is preferable to provide it.

In the present invention, the processing gas G is composed of a discharge gas and a thin film forming gas, and the discharge gas contains at least 90% by volume of nitrogen gas. The thin film forming gas is composed of a raw material gas that is a raw material for a deposited film and a reactive gas that promotes decomposition. The auxiliary gas CG is made of an inert gas such as a rare gas or nitrogen, and preferably has the same composition as the discharge gas in the processing gas G or the same composition as the discharge gas and the reactive gas.

Further, the flow rate at which the auxiliary gas is blown out is preferably equal to or higher than the flow rate at which the processing gas G is blown at the supply port of the processing gas supply means 30 to 5 times or less. If it is less than this, the effect of the auxiliary gas is small, and if it is 5 times or more, it becomes difficult to supply the processing gas G to the discharge space 100.

The angle θ between the blowing port for blowing the auxiliary gas CG to the roll electrodes 10A and 10C and the blowing direction of the processing gas G is set between 0 ≦ θ <90 °, and the effect of the accompanying gas as well as the effect of the auxiliary gas CG. Mixing between the side surface of the processing gas supply means 30 and the roll electrodes 10A and 10C can be prevented. And preferably 0 ≦ θ <60 °, more preferably 0 ≦ θ <30 °. This is because when the angle is 90 ° or more, the component of the auxiliary gas CG toward the discharge space 100 decreases, and the effect cannot be obtained. Here, θ is an angle formed by the direction in which the processing gas blows out and the direction in which the auxiliary gas blows out. The material of the gas supply unit 30 for supplying the processing gas G and the auxiliary gas CG is preferably an insulating material such as ceramic such as alumina or resin, and particularly preferably a heat resistant resin such as PEEK (polyether ether ketone).

FIG. 10 is a schematic view showing another example of the gas supply means applicable to the plasma discharge treatment apparatus of the present invention.

The basic configuration of the plasma discharge processing apparatus shown in FIG. 10 is substantially the same as that of the plasma discharge processing apparatus shown in FIG. 3 described above, and a new configuration is added to the processing gas supply means 30. In FIG. 10, as means for blocking the leaked processing gas G, one end having a width dimension equal to or larger than that of the processing gas supply means 30 contacts the outer peripheral surface of the roll electrodes 10A and 10C, and the other end is processed. A blade 32 attached to the gas supply means 30 is provided for each roll electrode.

Here, the blade 32 applicable to the present invention will be further described. The blade 32 is an insulating resin or rubber. Examples of the resin include polyolefin (PO) resins such as homopolymers or copolymers such as ethylene, polypropylene, and butene, and amorphous polyolefin resins (APO) such as cyclic polyolefins. Polyester resin such as polyethylene terephthalate (PET) and polyethylene 2.6-naphthalate (PEN), polyamide (PA) resin such as nylon 6, nylon 12, copolymer nylon, polyvinyl alcohol (PVA) resin, ethylene-vinyl alcohol Polyvinyl alcohol resin such as copolymer (EVOH), polyimide (PI) resin, polyetherimide (PEI) resin, polysulfone (PS) resin, polyethersulfone (PES) resin, polyetheretherketone (PEEK) Resin, polycarbonate (PC) resin, polyvinyl butyrate (PVB) resin, polyarylate (PAR) resin, ethylene-tetrafluoroethylene copolymer (ETFE), ethylene trifluoride chloride (PFA), tetrafluoroethylene Use fluororesin such as perfluoroalkyl vinyl ether copolymer (FEP), vinylidene fluoride (PVDF), vinyl fluoride (PVF), perfluoroethylene-perfluoropropylene-perfluorovinyl ether copolymer (EPA) can do. In particular, it is preferable to use a heat-resistant resin such as polycarbonate, polyether sulfone, polyether ether ketone, or polyimide. The insulation of the blade is preferably a volume resistance of 10 ¹⁰ Ωcm or more, more preferably 10 ¹² Ωcm or more.

Also, examples of rubber materials include chloroprene rubber, fluoro rubber, and silicon rubber, which are excellent in wear resistance, weather resistance, and heat aging resistance. In particular, fluororubber having a low gas permeability is preferably used. The hardness at this time is preferably 60 to 85 degrees (JIS K 6253-1997 standard).

Further, the end portion of the blade has a round cut surface so that the formed thin film is not damaged by coming into contact with the end portion of the blade 32. Further, as shown in FIG. 10, the shape in which the blade 32 is in contact with the outer peripheral surface of the roll electrode 10A and the shape in contact with the outer peripheral surface of the roll electrode 10B are shapes that are in the rotation direction of the roll electrode.

FIG. 11 is a schematic diagram showing another example of gas supply means applicable to the plasma discharge treatment apparatus of the present invention.

The basic configuration of the plasma discharge processing apparatus shown in FIG. 1 is substantially the same as that of the plasma discharge processing apparatus shown in FIG. 3 described above, and a new configuration is added to the processing gas supply means 30. As means for blocking the leaked processing gas G, a nip roller 31 having a width dimension equal to or larger than that of the processing gas supply means 30 is disposed so as to contact the roll electrodes 10A and 10B, and is used for conveying the substrate. Along with this, it is driven to rotate. This is to prevent the substrate surface from being scratched when the substrate F abuts against the nip roller 31.

Also, each of the pair of roll electrodes has a blade that is in contact with the nip roller at one end and a blade that is attached to the processing gas supply means.

The nip roller 31 is preferably one that does not easily damage the surface of the functional thin film formed on the substrate, and is preferably hard rubber, plastic, or the like. More specifically, the nip roller 31 has a rubber hardness of 60 to 80 according to JIS K 6253-1997 standard. Plastic and rubber rolls are preferred.

The blade 32 having the same material and shape as the blade 32 described in FIG. 10 can be applied.

Next, details of main components of the plasma discharge treatment apparatus of the present invention will be described.

[Roll electrode]
FIG. 12 is a perspective view showing an example of a roll electrode applicable to the present invention.

The configuration of the roll electrode 10 will be described. In FIG. 12A, the roll electrode 10 is inorganic after a ceramic is sprayed on a conductive base material 200a (hereinafter also referred to as “electrode base material”) such as metal. It is composed of a combination in which a ceramic-coated dielectric 200b (hereinafter also simply referred to as “dielectric”) coated with a material is covered. As the ceramic material used for thermal spraying, alumina, silicon nitride, or the like is preferably used. Among these, alumina is more preferably used because it is easily processed.

Further, as shown in FIG. 12B, the roll electrode 10 ′ may be configured by a combination of a conductive base material 200A such as metal covered with a lining dielectric 200B provided with an inorganic material by lining. As the lining material, silicate glass, borate glass, phosphate glass, germanate glass, tellurite glass, aluminate glass, vanadate glass and the like are preferably used. Of these, borate glass is more preferred because it is easy to process.

Examples of the conductive base materials 200a and 200A such as metal include metals such as silver, platinum, stainless steel, aluminum, and iron. Stainless steel is preferable from the viewpoint of processing.

It is desirable to adjust the temperature of each roll electrode 10 according to the present invention as necessary, such as heating or cooling. For example, a liquid is supplied into the roll electrode to control the temperature of the electrode surface and the temperature of the substrate. As the liquid that gives temperature, an insulating material such as distilled water or oil is preferable. Although the temperature of the substrate varies depending on the treatment conditions, it is usually preferably room temperature to 200 ° C., more preferably room temperature to 120 ° C.

The surface of the roll electrode is required to have high smoothness because the base material is in close contact and the base material and the electrode are transferred and rotated synchronously. The smoothness is expressed as the maximum surface roughness height (Rmax) and centerline average surface roughness (Ra) specified in JIS B 0601. Rmax of the surface roughness of the roll electrode according to the present invention is preferably 10 μm or less, more preferably 8 μm or less, and particularly preferably 7 μm or less. Further, Ra is preferably 0.5 μm or less, and more preferably 0.1 μm or less.

In the present invention, the gap between the roll electrodes is determined in consideration of the thickness of the solid dielectric, the magnitude of the applied voltage, the purpose of using plasma, the shape of the electrode, and the like. The distance between the electrode surfaces is preferably 0.5 to 20 mm, more preferably 0.5 to 5 mm, and particularly preferably 1 mm ± 0.5 mm from the viewpoint of uniformly generating plasma discharge. In the present invention, the gap between the roll electrodes refers to a distance at which the opposing electrode surfaces are closest to each other. The diameter of the roll electrode is preferably 10 to 1000 mm, more preferably 20 to 500 mm. The peripheral speed of the roll electrode is 1 to 100 m / mim, more preferably 5 to 50 m / mim.

[Process gas]
The processing gas used in the plasma discharge processing apparatus of the present invention will be described.

In the present invention, a mixed gas of a discharge gas and a thin film forming gas (also called a reactive gas) is used as the processing gas, and the discharge gas contains at least 90% by volume of nitrogen gas.

(Discharge gas)
Commonly used discharge gas (also referred to as rare gas) elements include nitrogen and Group 18 elements of the periodic table, specifically nitrogen, helium, neon, argon, krypton, xenon, radon, and the like. As is known, the present invention is characterized in that the discharge gas contains at least 90% by volume of nitrogen gas. If the concentration of the nitrogen gas in the processing gas is 90% by volume or more compared to the rare gas, the effect of the present invention is remarkably exhibited and stable plasma can be generated. 90 to 99.99% by volume is particularly preferable. Nitrogen gas is necessary for generating a plasma discharge, and the reactive gas in the plasma discharge is ionized or radicalized to contribute to the surface treatment.

(Thin film forming gas)
In the present invention, as the thin film forming gas, various substances are used depending on the type of the functional thin film formed on the substrate. For example, a low refractive index layer and an antifouling layer useful for an antireflection layer can be formed by using an organic fluorine compound as a thin film forming gas, and useful for an antireflection layer by using a silicon compound. A low refractive index layer or a gas barrier layer can also be formed. Further, by using an organometallic compound containing a metal such as Ti, Zr, Sn, Si, or Zn, a metal oxide layer or a metal nitride layer can be formed. A useful medium refractive index layer or high refractive index layer can be formed, and a conductive layer or an antistatic layer can also be formed.

Thus, preferred examples of the reactive gas substance useful in the present invention include organic fluorine compounds and metal compounds.

The reactive fluorine-containing organic fluorine compound preferably used in the present invention is preferably a gas such as fluorocarbon or fluorohydrocarbon, such as tetrafluoromethane, hexafluoroethane, 1,1,2,2-tetrafluoro. Examples thereof include, but are not limited to, fluorocarbon compounds such as ethylene, 1,1,1,2,3,3-hexafluoropropane and hexafluoropropene. It is preferable to select a compound that does not generate corrosive gas or harmful gas by plasma discharge treatment as the organic fluorine compound, but it is also possible to select a condition in which they are not generated. When an organic fluorine compound is used as a reactive gas useful in the present invention, it is preferable that the organic fluorine compound is a gas at room temperature and normal pressure as it can be used as it is as the most suitable reactive gas component for accomplishing the purpose. On the other hand, in the case of a liquid or solid organic fluorine compound at room temperature and normal pressure, it may be used after being vaporized by means of a vaporizer such as heating or decompression, or dissolved or sprayed in an appropriate organic solvent. You may evaporate and use.

When the above organic fluorine compound is used in the treatment gas, the content of the organic fluorine compound in the treatment gas is 0.01 to 10% by volume from the viewpoint of forming a uniform thin film on the substrate by plasma discharge treatment. Preferably, it is 0.1 to 5% by volume. These may be used alone or in combination.

The reactive gas metal compounds preferably used in the present invention include Al, As, Au, B, Bi, Ca, Cd, Cr, Co, Cu, Fe, Ga, Ge, Hg, In, Li, and Mg. , Mn, Mo, Na, Ni, Pb, Pt, Rh, Sb, Se, Si, Sn, V, W, Y, Zn, Zr, and other metal compounds or organometallic compounds, Al, Ge, In, Sb, Si, Sn, Ti, W, Zn, or Zr is preferably used as the organometallic compound.

Among these, examples of silicon compounds include silicon such as alkyl silanes such as dimethylsilane and tetramethylsilane, tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, dimethyldiethoxysilane, methyltrimethoxysilane, and ethyltriethoxysilane. Examples include organosilicon compounds such as alkoxides; silicon hydrogen compounds such as monosilane and disilane, halogenated silicon compounds such as dichlorosilane, trichlorosilane, and tetrachlorosilane, and other organosilanes, all of which can be preferably used. The present invention is not limited to these. Moreover, these can be used in combination as appropriate. From the viewpoint of handling, the above organosilicon compounds are preferably silicon alkoxides, alkylsilanes, and organosilicon hydrogen compounds. They are not corrosive, do not generate harmful gases, and have little contamination in the process. Silicon alkoxide is preferred.

The metal compound other than silicon as the reactive gas useful in the present invention is not particularly limited, and examples thereof include an organometallic compound, a metal halide compound, and a metal hydrogen compound. The organic component of the organometallic compound is preferably an alkyl group, an alkoxide group, or an amino group, and preferred examples include tetraethoxy titanium, tetraisopropoxy titanium, tetrabutoxy titanium, and tetradimethylamino titanium. Examples of the metal halide compound include titanium dichloride, titanium trichloride, and titanium tetrachloride. Further, examples of the metal hydrogen compound include monotitanium and dititanium. In the present invention, a titanium-based organometallic compound can be preferably used.

In order to introduce the organometallic compound into the discharge part, any of gas, liquid or solid may be used at normal temperature and pressure, but if it is liquid or solid, heating It may be used after being vaporized by means of a vaporizer such as reduced pressure or ultrasonic irradiation. In the present invention, it is preferably vaporized and evaporated to be used as a gas. If the boiling point of the liquid organometallic compound at room temperature and normal pressure is 200 ° C. or less, vaporization can be facilitated, which is suitable for the production of the thin film of the present invention. Further, when the organometallic compound is a metal alkoxide such as tetraethoxysilane or tetraisopropoxytitanium, it is easily dissolved in an organic solvent, so that it can be diluted with an organic solvent such as methanol, ethanol, n-hexane or the like. Good. An organic solvent may be used as a mixed solvent.

In the present invention, when an organometallic compound is used as a reactive gas in a processing gas, the content in the processing gas is preferably 0.01 to 10% by volume, more preferably 0.1 to 5%. % By volume. The above metal compounds may be used by mixing several kinds of the same or different metal compounds.

In addition, hydrogen, oxygen, nitrogen, nitrogen monoxide, nitrogen dioxide, carbon dioxide, ozone, hydrogen peroxide are used as reactive gases of the above organic fluorine compounds and organometallic compounds or any of the above compounds with respect to rare gases. The mixture may be used in an amount of 0.1 to 10% by volume, and by using such an auxiliary, the hardness of the thin film can be remarkably improved.

When the substrate applied to the present invention is a film having an antireflection layer, for example, an organosilicon compound is suitable for forming a low refractive index layer, and a titanium-based organometallic compound forms a high refractive index layer. Any of them is preferably used. Moreover, the refractive index can be controlled by adjusting the mixing ratio using a gas in which these are mixed, so that a medium refractive index layer can be obtained.

The low-refractive index layer and the high-refractive index layer formed by plasma discharge treatment using the above processing gas are thought to be mainly composed of metal oxides, if not all. For example, in a laminate of a low refractive index layer made of an organic silicon compound and a high refractive index layer made of an organic titanium compound, the low refractive index layer has silicon oxide and the high refractive index layer has titanium oxide as a main component. It is preferable. At this time, a small amount of silicon oxide may be mixed in the high refractive index layer mainly composed of titanium oxide, and conversely, a small amount of titanium oxide may be mixed in the low refractive index layer mainly composed of silicon oxide. Also good. By such mixing, the adhesion (adhesiveness) of each layer can be improved. Of course, an organic metal compound or fluorine-containing compound other than the main component can be mixed and added to the processing gas for adjusting the refractive index to the desired purpose or for other purposes, and the processing gas is supplied from the processing gas supply unit. It is preferable to mix appropriately at the stage before supply. As described above, the discharge portion is filled with the processing gas, and even if the entrained air slightly enters the processing chamber, the influence of a minute amount of air (oxygen or nitrogen) or moisture can be ignored in practice. Depending on the processing conditions, there may be a case where processing is performed by intentionally adding air (oxygen or nitrogen) or moisture to the processing gas.

〔Base material〕
Next, the base material according to the present invention will be described.

Examples of the substrate according to the present invention include a cellulose ester film, a polyester film, a polycarbonate film, a polystyrene film, a polyolefin film, a polyvinyl alcohol film, a cellulose film, and other resin films. For example, a cellulose ester film As cellulose diacetate film, cellulose acetate butyrate film, cellulose acetate propionate film, cellulose acetate phthalate film, cellulose triacetate, cellulose nitrate; as polyester film, polyethylene terephthalate film, polyethylene naphthalate film, polybutylene phthalate film 1,4-dimethylenecyclohexylene tele Tallate or copolyester film of these structural units; polycarbonate film of bisphenol A; polystyrene film: syndiotactic polystyrene film; polyolefin film: polyethylene film, polypropylene film; polyvinyl alcohol film as polyvinyl alcohol Film, ethylene vinyl alcohol film; cellophane as cellulose film; norbornene resin film, polymethylpentene film, polyetherketone film, polyimide film, polyethersulfone film, polysulfone film, poly Ether ketone imide film, polyamide fill It can fluororesin film, nylon film, polymethyl methacrylate film, an acrylic film or polyarylate film, be mentioned polyvinylidene chloride film or the like.

A film obtained by appropriately mixing these film materials can also be preferably used. For example, a film obtained by mixing a commercially available resin such as ZEONEX (manufactured by Nippon Zeon Co., Ltd.) or ARTON (manufactured by Nippon Synthetic Rubber Co., Ltd.) can also be used. In addition, even for materials having a high intrinsic birefringence such as polycarbonate, polyarylate, polysulfone or polyether sulfone, the conditions such as solution casting or melt extrusion, and further the conditions for stretching in the vertical and horizontal directions, etc. By appropriately setting, a base material suitable for the present invention can be obtained. In the present invention, the film is not limited to the above-described film.

As the thickness of the substrate suitable for the plasma discharge treatment apparatus of the present invention, a film of about 10 to 1000 μm can be preferably used, more preferably 10 to 200 μm, and particularly a thin substrate of 10 to 60 μm. It can be preferably used.

[Thin films, laminates and films]
In the present invention, the thin film is formed by subjecting the base material to plasma discharge treatment with the above treatment gas at atmospheric pressure or a pressure in the vicinity thereof at the discharge portion in the gap between the counter electrodes. In the present invention, the plasma discharge treatment under atmospheric pressure or a pressure in the vicinity thereof can be performed with a substrate having a very wide width of, for example, 2000 mm, and a treatment speed of 100 m / min. You can also. In the present invention, when plasma discharge is started, first, a processing gas or a rare gas is introduced into the processing chamber while drawing the air in the processing chamber with a vacuum pump, and the processing gas is supplied to the discharge section after replacing the air. The discharge part is preferably filled. Thereafter, the substrate is transferred to carry out processing.

The film thickness can be appropriately adjusted according to the discharge part, the processing gas concentration, and the conveyance speed of the substrate.

The thin film formed on the substrate by the plasma discharge treatment apparatus of the present invention is only on one side, but after winding up, the opposite side may be passed through the apparatus for plasma discharge treatment. When the antistatic layer is formed of a metal oxide, the antistatic layer or the conductive layer is formed by applying a coating liquid such as metal oxide fine particles or crosslinked cationic polymer particles into a layer having a thickness of about 0.1 to 2 μm. Although it can be formed by coating, a thin conductive layer can also be formed by the plasma discharge treatment apparatus of the present invention. For example, a conductive layer of metal oxide such as tin oxide, indium oxide, or zinc oxide may be formed. In addition, easy adhesion processing described in JP-A-2002-82223, antistatic processing described in Japanese Patent Application No. 2000-80043, and the like can be performed using the plasma discharge processing apparatus of the present invention.

The conditions for forming a thin film by the plasma discharge processing apparatus of the present invention have been described in the above-mentioned plasma discharge processing apparatus, but other conditions for processing are also described.

When forming the thin film of the present invention, it is easy to form a uniform thin film by subjecting the substrate to heat treatment at 50 to 120 ° C. and then plasma discharge treatment, and preheating is a preferable method. By performing the heat treatment, the substrate that has absorbed moisture can be dried, and it is preferable to perform a plasma discharge treatment while maintaining a low humidity. It is preferable to perform plasma discharge treatment without absorbing moisture on a substrate conditioned at less than 60% RH, more preferably 40% RH. The moisture content is preferably 3% or less, more preferably 2% or less, and still more preferably 1% or less.

Further, the thin film can be stabilized by heat-treating the substrate after the plasma discharge treatment in a heat treatment zone at 50 to 130 ° C. for 1 to 30 minutes, which is an effective means.

Furthermore, when a laminate is produced by the multistage plasma discharge treatment of the present invention, the treatment surface may be irradiated with ultraviolet rays before and after each plasma discharge treatment, and the adhesion (adhesion) of the formed thin film to the substrate And stability can be improved. The amount of ultraviolet irradiation is preferably 50 to 2000 mJ / cm ² , and if it is less than 50 mJ / cm ² , the effect is not sufficient, and if it exceeds 2000 mJ / cm ² , the substrate may be deformed.

The film thickness of the thin film formed in the present invention is preferably in the range of 1 to 1000 nm.

The film thickness deviation with respect to the average film thickness of the thin film formed by the plasma discharge treatment apparatus of the present invention is small, and a uniform thin film can be formed, which is an excellent thin film forming method. A film thickness deviation of ± 10% can be easily obtained, and a uniform thin film preferably within ± 5%, particularly within ± 1% can be obtained.

The composition coating liquid containing inorganic or organic fine particles described above is coated on a substrate and dried, and the surface is formed on a functional layer having an uneven surface such as Ra of about 0.1 to 0.5 μm, such as an antiglare layer. A thin film having a uniform thickness can also be formed by the discharge treatment. For example, when the thin film is a low refractive index layer or a high refractive index layer, it can be provided as an optical interference layer.

The film of the present invention is composed of a thin film formed by the plasma discharge treatment apparatus of the present invention and a laminate thereof.

Examples of the film of the present invention include an antireflection film, an antiglare antireflection film, an electromagnetic wave shielding film, a conductive film, an antistatic film, a retardation film, an optical compensation film, a viewing angle widening film, and a brightness enhancement film. However, it is not limited to these.

Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. In addition, although the display of "part" or "%" is used in an Example, unless otherwise indicated, "part by mass" or "mass%" is represented.

Example 1
<< Preparation of thin layer laminate >>
[Preparation of thin-layer laminate 1: comparative example]
As a base material, an atmospheric pressure plasma discharge treatment apparatus (using only a single power source) that can simultaneously form a thin film on a different base material shown in FIG. 6 on a roll-shaped polyethylene terephthalate film having a thickness of 100 μm. Application method A), the diameter of each roll electrode is 300 mm and the roll electrodes 10A and 10B having the discharge distance L pattern shown in FIG. 2 are changed to the antireflection film under the following discharge conditions. The thin film stack 1 was manufactured by forming the film thickness to be 100 nm. In addition, the atmospheric pressure plasma discharge processing apparatus using the roll electrode of the same diameter used for production of the thin layered product 1 is referred to as FIG. 6 ′ for convenience.

Each roll electrode used was manufactured by covering a dielectric with 1 mm of an alumina molten dielectric on one side and setting the gap between the roll electrodes to 1 mm. Furthermore, the roll electrode used the stainless steel jacket roll base material which has the cooling function by a cooling water. During the plasma discharge, the temperature of the roll rotating electrode was adjusted and kept at 80 ° C.

(Deposition conditions)
<Discharge gas> Argon gas 94.9% by volume
<Thin film forming gas>
Source gas: Tetraethoxysilane (mixed with argon gas by a vaporizer manufactured by Lintec Corporation and vaporized) 0.1% by volume
Reaction gas: Oxygen gas 5.0% by volume
(Power requirements)
Power supply: High frequency power supply made by Pearl Industrial Co., Ltd. Frequency 27MHz
Output density 10W / cm ²
[Preparation of thin-layer laminate 2: comparative example]
As a base material, a roll electrode having a discharge distance L pattern as shown in FIG. 2 on a roll-shaped polyethylene terephthalate film having a thickness of 100 μm and having a diameter of 300 mm as a roll electrode according to the folded conveying method shown in FIG. Using an atmospheric pressure plasma discharge treatment apparatus having 10A and 10B (application method B in which the first high-frequency electric field and the second high-frequency electric field are superimposed), the film thickness of the antireflection film becomes 100 nm under the following discharge conditions. Thus, a thin film laminate 2 was produced. The roll electrode was the same as that used in the production of the thin film laminate 1. In addition, the atmospheric pressure plasma discharge processing apparatus using the roll electrode of the same diameter used for production of the thin layered product 2 is referred to as FIG. 7 ′ for convenience.

(Deposition conditions)
<Discharge gas> Nitrogen gas 94.9% by volume
<Thin film forming gas>
Source gas: Tetraethoxysilane (mixed with nitrogen gas and vaporized by a Lintec vaporizer) 0.1% by volume
Reaction gas: Oxygen gas 5.0% by volume
(Power requirements)
First power supply side:
Frequency 80kHz
Output density 5W / cm ²
Second power supply side:
Frequency 13.56MkHz
Output density 5W / cm ²
[Preparation of Thin Layer Laminate 3: Comparative Example]
As a base material, a roll electrode having a discharge distance L pattern as shown in FIG. 2 on a roll-shaped polyethylene terephthalate film having a thickness of 100 μm and having a diameter of 300 mm as a roll electrode in a loop conveyance system as shown in FIG. A thin film laminate 3 was produced in the same manner except that an atmospheric pressure plasma discharge treatment apparatus having 10A and 10B (application method B in which the first high-frequency electric field and the second high-frequency electric field were superimposed) was used. In addition, the atmospheric pressure plasma discharge processing apparatus using the roll electrode of the same diameter used for production of the thin layered product 3 is referred to as FIG. 5 ′ for convenience.

[Preparation of Thin Layer Laminate 4: Present Invention]
A polyethylene terephthalate film having a thickness of 100 μm is set as a base material in a vacuum chamber of a vacuum vapor deposition apparatus having the roll electrode configuration shown in FIG. 6, and after vacuum degassing to 10 ⁻⁴ Pa, tetraethoxysilane (TEOS) A thin film laminate is formed by forming an antireflection film having a thickness of 100 nm while appropriately adjusting the supply amount of raw materials using hydrogen gas and helium gas under conditions of an applied voltage (RF power) of 100 W and a substrate temperature of 180 ° C. 4 was produced.

Each roll electrode used was manufactured by coating a dielectric with 1 mm of alumina molten dielectric on a dielectric, and the gap between the electrodes was set to 1 mm on the roll electrode, and the roll electrode 10A had a diameter of 100 mm. The diameter of the electrode 10C is 85 mm, and the diameter ratio is 1.0: 0.85. Moreover, the discharge distance L pattern of each roll electrode was the pattern shown in FIG.

[Preparation of Thin Layered Laminate 5: Present Invention]
As a base material, an atmospheric pressure plasma discharge treatment apparatus (using only a single power source) that can simultaneously form a thin film on a different base material shown in FIG. 6 on a roll-shaped polyethylene terephthalate film having a thickness of 100 μm. 4 is used, and the roll electrode 10A having the discharge distance L pattern shown in FIG. 4 and a roll electrode 10C having a diameter of 255 mm (diameter ratio of the roll electrodes 10A and 10C) is used as the roll electrode. 1.0: 0.85), and the antireflection film was formed to a thickness of 100 nm under the following discharge conditions to produce a thin film laminate 5.

In addition, each used roll electrode 10A, 10C was manufactured by covering a dielectric with an alumina molten dielectric with a thickness of 1 mm and setting the gap between the roll electrodes to 1 mm. Furthermore, the roll electrode used the stainless steel jacket roll base material which has the cooling function by a cooling water. During the plasma discharge, the temperature of the roll rotating electrode was adjusted and kept at 80 ° C.

(Deposition conditions)
<Discharge gas> Argon gas 94.9% by volume
<Thin film forming gas>
Source gas: Tetraethoxysilane (mixed with argon gas by a vaporizer manufactured by Lintec Corporation and vaporized) 0.1% by volume
Reaction gas: Oxygen gas 5.0% by volume
(Power requirements)
Power supply: High frequency power supply made by Pearl Industrial Co., Ltd. Frequency 27MHz
Output density 10W / cm ²
[Preparation of Thin Layer Laminate 6: Present Invention]
In the production of the thin layered product 5, a thin layered product 6 was produced in the same manner except that the discharge gas and the raw material vaporizing gas were changed from argon gas to nitrogen gas.

[Preparation of Thin Layer Laminate 7: Present Invention]
In an atmospheric pressure plasma discharge treatment apparatus capable of simultaneously forming a thin film on a different polyethylene substrate as shown in FIG. 6 on a roll-shaped polyethylene terephthalate film having a thickness of 100 μm as a substrate, the following 2 are shown as power supply conditions. Changed to the frequency system, the roll electrode 10A having a diameter of 300 mm and the roll electrode 10C having a diameter of 255 mm (the diameter ratio of the roll electrodes 10A and 10C is 1.0: 0.85) are used as the roll electrodes. Using the atmospheric pressure plasma discharge treatment apparatus (application method B in which the first high-frequency electric field and the second high-frequency electric field are superimposed) having the discharge distance L pattern described above, the film thickness of the antireflection film is as follows. A thin film stack 7 was produced by forming the film so as to have a thickness of 100 nm. The roll electrode was the same as that used in the production of the thin film laminate 1.

(Deposition conditions)
<Discharge gas> Nitrogen gas 94.9% by volume
<Thin film forming gas>
Source gas: Tetraethoxysilane (mixed with nitrogen gas and vaporized by a Lintec vaporizer) 0.1% by volume
Reaction gas: Oxygen gas 5.0% by volume
(Power requirements)
First power supply side:
Frequency 80kHz
Output density 5W / cm ²
Second power supply side:
Frequency 13.56MkHz
Output density 5W / cm ²
[Preparation of Thin Layer Laminate 8: Present Invention]
As a base material, a two-frequency atmospheric pressure plasma discharge treatment apparatus having a folding distance L pattern shown in FIG. 4 having a folding transport mechanism shown in FIG. 7 on a roll-shaped polyethylene terephthalate film having a thickness of 100 μm. Using a roll electrode 10A having a diameter of 300 mm and a roll electrode 10C having a diameter of 255 mm (the diameter ratio of the roll electrodes 10A and 10C is 1.0: 0.85) under the power supply conditions shown below. Using an atmospheric pressure plasma discharge processing apparatus (application method B in which the first high-frequency electric field and the second high-frequency electric field are superimposed), the antireflection film is formed to a thickness of 100 nm, and the thin film stack 8 is formed. Produced. The roll electrode was the same as that used in the production of the thin film laminate 1.

(Deposition conditions)
<Discharge gas> Nitrogen gas 94.9% by volume
<Thin film forming gas>
Source gas: Tetraethoxysilane (mixed with nitrogen gas and vaporized by a Lintec vaporizer) 0.1% by volume
Reaction gas: Oxygen gas 5.0% by volume
(Power requirements)
First power supply side:
Frequency 80kHz
Output density 5W / cm ²
Second power supply side:
Frequency 13.56MkHz
Output density 5W / cm ²
[Preparation of Thin Layer Laminate 9: Present Invention]
In the production of the thin layered laminate 8, the atmospheric pressure plasma discharge treatment apparatus having the loop conveyance mechanism shown in FIG. 8 is replaced with the atmospheric pressure plasma discharge treatment apparatus having the loop conveyance mechanism shown in FIG. Similarly, a thin film laminate 9 was produced.

[Preparation of Thin Layer Laminate 10: Present Invention]
In the production of the thin layered product 8, the roll electrode 10A having a diameter of 300 mm and the roll electrode 10C having a diameter of 285 mm (the diameter ratio of the roll electrodes 10A and 10C is 1.0: 0) as the roll electrode forming the discharge space. .95) was used in the same manner to produce a thin layer laminate 10.

[Preparation of Thin Layered Laminate 11: Present Invention]
In the production of the thin layered product 8, the roll electrode 10A having a diameter of 300 mm and the roll electrode 10C having a diameter of 195 mm (the diameter ratio of the roll electrodes 10A and 10C is 1.0: 0) as the roll electrode forming the discharge space. The thin layer laminate 11 was produced in the same manner except that.

[Preparation of Thin Layered Laminate 12: Present Invention]
In the production of the thin layered product 8, the roll electrode 10A having a diameter of 300 mm and the roll electrode 10C having a diameter of 150 mm (the diameter ratio of the roll electrodes 10A and 10C is 1.0: 0) as the roll electrode forming the discharge space. .50) was used in the same manner to produce a thin laminate 12.

[Preparation of Thin Layer Laminate 13: Present Invention]
As a base material, a roll-like polyethylene terephthalate film having a thickness of 100 μm is composed of a folding conveyance mechanism shown in FIG. 3, and has a discharge distance L pattern shown in FIG. Using the single-frequency atmospheric pressure plasma discharge treatment apparatus provided, the roll electrode 10A having a diameter of 300 mm and the roll electrode 10C having a diameter of 255 mm (diameter ratio of the roll electrodes 10A and 10C) as a roll electrode under the following power supply conditions 1.0: 0.85), the antireflection film was formed to a thickness of 100 nm, and the thin film laminate 13 was produced. The roll electrode was the same as that used in the production of the thin film laminate 1.

(Deposition conditions)
<Discharge gas> Nitrogen gas 94.9% by volume
<Thin film forming gas>
Source gas: Tetraethoxysilane (mixed with nitrogen gas and vaporized by a Lintec vaporizer) 0.1% by volume
Reaction gas: Oxygen gas 5.0% by volume
(Power requirements)
Power supply: High frequency power supply made by Pearl Industrial Co., Ltd. Frequency 27MHz
Output density 10W / cm ²
[Preparation of thin-layer laminate 14: the present invention]
In the production of the thin layered product 13, the atmospheric pressure plasma discharge treatment apparatus having the gas supply means shown in FIG. 10 is used instead of the atmospheric pressure plasma discharge treatment apparatus having the configuration shown in FIGS. Similarly, the thin layered product 14 was produced.

[Preparation of Thin Layered Laminate 15: Present Invention]
In the production of the thin layered product 13, the atmospheric pressure plasma discharge treatment apparatus having the gas supply means shown in FIG. 11 is used instead of the atmospheric pressure plasma discharge treatment apparatus having the configuration shown in FIGS. Similarly, a thin layered laminate 15 was produced.

[Preparation of Thin Layer Laminate 16: Present Invention]
In the production of the thin layer laminate 13, the thin layer laminate 16 was produced in the same manner except that the gas supply means shown in FIG. 9 was removed and only the atmospheric pressure plasma discharge treatment apparatus having the configuration shown in FIG. 3 was used. .

<< Evaluation of thin film laminate >>
The following evaluations were performed on each of the prepared thin film formed bodies.

(Evaluation of thin film unevenness resistance)
About each produced said thin film formation body, the antireflection film formation surface was irradiated with light diagonally, the presence or absence of thin film unevenness was visually observed, and thin film unevenness tolerance was evaluated according to the following criteria.

A: Unevenness of the formed thin film is not recognized at all. O: An extremely weak thin film unevenness is observed, but the film surface is almost in good condition. Δ: Periodic generation of the weak thin film unevenness is observed. Acceptable quality ×: Strong thin film irregularities occur periodically and become a practical problem. XX: Extremely thin thin film irregularities occur periodically, and the quality is constant for practical use (Thin film uniformity) 1 rating)
About each produced said thin film forming body, the film thickness of 100 places was measured at random using the thin film measuring apparatus F20-UV made from FILMETRICS, the standard deviation of the film thickness was computed, and the following reference | standard evaluated.

◎: Standard deviation of film thickness is 0 to less than 1 nm ○: Standard deviation of film thickness is less than 1 to 2 nm △: Standard deviation of film thickness is less than 2 to 5 nm ×: Standard deviation of film thickness is 5 nm or more (thin film uniformity Evaluation of 2: measurement of yield)
A sample of 250 cm ² is cut out from an arbitrary position of each of the thin film formed bodies described above, the area where the thin film unevenness is clearly measured is measured, the yield is measured from the following formula, and the thin film uniformity is determined according to the following criteria. Evaluation of 2 was performed.

Yield (%) = {(250 cm ² −thin film unevenness occurrence area) / 250 cm ² } × 100
◎: Yield is 95% or more ○: Yield is 90% or more and less than 95% △: Yield is 85% or more and less than 90% ×: Yield is 75% or more and less than 85% Xx: Yield is less than 75% (Evaluation of thin film hardness)
About the antireflection film formation surface of each of the produced thin film formed bodies, the hardness of each antireflection film was measured by a pencil scratch test method based on JIS K 5400.

The hardness rank is (soft) 6B to B, HB, F, H to 9H (hard) in the order 6B is the softest, and 9H is the hardest.

Table 1 shows the results obtained as described above.

As is apparent from the results shown in Table 1, the roll electrode has a diameter ratio in the range of 1.00: 0.55 to 1.00: 0.95. The thin film laminate produced by the plasma discharge treatment apparatus of the present invention used by volume% or more was formed with respect to the thin film laminate produced by the plasma discharge treatment apparatus comprised of roll electrodes having the same diameter as a comparative example ( It can be seen that the anti-reflection film is excellent in uniformity, thin film unevenness resistance, and hardness.

In the thin film laminate of the present invention, an atmospheric pressure plasma discharge processing apparatus is used as a thin film forming apparatus, a two-frequency system is used as a high-frequency power source, and gas supply means shown in FIGS. It turns out that the said effect is exhibited further.

Example 2
In the production of the thin film laminates 1 to 15 described in the examples, instead of tetraethoxysilane, tetraisopropoxy titanium (titanium oxide film), ethylene, methane (carbon film), manufactured by GE Toshiba Silicon Co. Each thin film laminate was prepared in the same manner except that heptadecafluorodecyltriisopropoxysilane (antifouling layer) was used, and each evaluation similar to the method described in Example 1 was performed. The same results as in Table 1 were obtained.

Example 3
The thin film laminate 2 produced in Example 1 was subjected to post-treatment for oxidizing the functional thin film under the following conditions using each plasma discharge treatment apparatus described in Table 2, and the thin film laminates 17 to 20 Was made.

<< Preparation of thin layer laminate >>
[Preparation of thin film laminate 17]
The atmospheric pressure plasma discharge treatment apparatus (first high frequency electric field) having the roll electrodes 10A and 10B having the discharge distance L pattern shown in FIG. And the second high-frequency electric field were superimposed on each other under the following discharge conditions to perform post-treatment (oxidation treatment) on the thin-film stack 2 to produce a thin-film stack 17. The roll electrode was the same as that used in the production of the thin film laminate 1.

(Post-processing conditions)
<Gas conditions>
Discharge gas: Nitrogen gas 96.0% by volume
Post-treatment gas: Oxygen gas 4.0% by volume
<Power supply conditions>
1st electrode side Power supply type High frequency power supply made by Applied Electric Company Frequency 80kHz
Output density 5W / cm ²
2nd electrode side Power supply type High frequency power supply made by Pearl Industry Co., Ltd. Frequency 13.56MHz
Output density 5W / cm
[Preparation of thin film laminate 18]
As a plasma discharge processing apparatus, an independent conveyance system (first high frequency electric field and second high frequency electric field) composed of roll electrodes having different diameters similar to those used in the production of the thin film formed body 7 described in Example 1 is used. A thin film laminate 18 was produced by performing the above-described post-treatment in the same manner as the thin film laminate 17 except that the plasma discharge treatment apparatus of the application method B) in which was applied was used.

[Preparation of thin film laminate 19]
As a plasma discharge processing apparatus, a folded conveyance system (first high frequency electric field and second frequency) composed of roll electrodes having different diameters shown in FIG. 7 similar to those used in the production of the thin film formed body 8 described in Example 1 is used. A thin film laminate 19 was produced by performing the above-described post-treatment in the same manner as the thin film laminate 17 except that the plasma discharge treatment apparatus of the application method B) in which the high frequency electric field was superimposed was used.

[Production of Thin Film Laminate 20]
As a plasma discharge processing apparatus, a loop conveyance system (first high-frequency electric field and second second) composed of roll electrodes having different diameters shown in FIG. 8 similar to those used for the production of the thin film-formed body 8 described in Example 1 is used. A thin film laminate 20 was produced by performing the above-mentioned post-treatment in the same manner as the thin film laminate 17 except that the plasma discharge treatment apparatus of the application method B) in which the high frequency electric field was superimposed was used.

<< Evaluation of thin layer laminate >>
About each produced thin film laminated body and the thin film laminated body 2 produced in Example 1, it evaluated the thin film hardness similarly to the method of Example 1, and measured the oxygen content according to the following method.

[Measurement of oxygen content]
The oxygen content in each thin film laminate was calculated by the XPS method described below, and the atomic concentration (atomic concentration) defined below was determined.

Concentration of oxygen atoms = number of oxygen atoms / number of all atoms × 100
Each thin film stack is a silicon oxide film, and the theoretical atomic number concentration of oxygen is 67%.

As the XPS surface analyzer, ESCALAB-200R manufactured by VG Scientific, Inc. was used in the present invention. Specifically, Mg was used for the X-ray anode, and measurement was performed at an output of 600 W (acceleration voltage: 15 kV, emission current: 40 mA). The energy resolution was set to be 1.5 eV to 1.7 eV when defined by the half width of a clean Ag3d5 / 2 peak.

As a measurement, first, the range of binding energy from 0 eV to 1100 eV was measured at a data acquisition interval of 1.0 eV to determine what elements were detected.

Next, with respect to all the detected elements except for the etching ion species, the data acquisition interval was set to 0.2 eV, and the photoelectron peak giving the maximum intensity was subjected to narrow scan, and the spectrum of each element was measured (in this case) , Silicon, oxygen, carbon, nitrogen, etc.).

The obtained spectrum is COMMON DATA PROCESSING SYSTEM manufactured by VAMAS-SCA-JAPAN (Ver. 2.3 or later is preferable) in order not to cause a difference in the content calculation result due to a difference in measuring apparatus or computer. After being transferred to the top, the content value of oxygen, which is an element of the analysis target, processed with the same software was obtained.

Table 2 shows the results obtained as described above.

As is clear from the results shown in Table 2, it can be seen that an excellent functional thin film with higher homogeneity can be obtained by performing post-treatment using the plasma processing apparatus defined in the present invention.

Moreover, about each said thin film laminated body, as a result of measuring oxygen content about 100 arbitrary positions in the width direction, and measuring the variation width (standard deviation), the thin film laminated body of this invention is compared with a comparative example. It was confirmed that the variation width of the oxygen content was small.

Claims (8)

1. A counter electrode composed of a pair of rotating roll electrodes, a plasma discharge space that generates a plasma discharge by applying a voltage between the counter electrodes, and a base material that passes through the plasma discharge space while being held by the counter electrode composed of the roll electrode And a processing gas supply means for supplying a processing gas to the plasma discharge space, wherein the processing gas includes a discharge gas and a thin film forming gas, and the discharge gas contains at least 90% by volume of nitrogen gas. A plasma discharge treatment apparatus characterized in that the diameter ratio of a pair of roll electrodes that are contained above and constitute the counter electrode is 1.00: 0.55 to 1.00: 0.95.
2. The plasma discharge treatment apparatus according to claim 1, wherein a functional thin film is formed on the substrate.
3. The plasma discharge processing apparatus according to claim 1 or 2, wherein the processing gas supply means supplies a processing gas having an atmospheric pressure or a pressure in the vicinity thereof between the counter electrodes.
4. 4. The plasma discharge according to claim 1, wherein the plasma discharge is a method in which a first high-frequency electric field and a second high-frequency electric field are superimposed to cause plasma discharge. 5. Plasma discharge treatment equipment.
5. The plasma discharge treatment apparatus according to any one of claims 1 to 4, wherein the substrate is folded and conveyed to form a functional thin film on the substrate.
6. The plasma discharge treatment according to any one of claims 1 to 5, wherein the substrate is continuously conveyed by a loop conveyance method to form a functional thin film on the substrate. apparatus.
7. A thin film laminate in which a functional thin film is formed on the surface of a base material using the plasma discharge treatment apparatus according to any one of claims 1 to 6.
8. The thin film laminate according to claim 7, wherein the functional thin film is an antireflection film.

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