JP2004217966A - Method and device for forming gas barrier film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To planarize the surface of a gas barrier film for intercepting oxygen and steam, which is formed on the surface of a film 23 made of plastic, and further to reduce the film thickness. <P>SOLUTION: This film-forming method comprises wrapping a plastic film 23 around a guiding drum 51 into a coil form, and suspension-transporting the film 23 from the first space 12 for surface treatment to the second space 13 for forming the gas barrier film, both of which are partitioned each other by a partition 14, in the space of a vacuum vessel 11; supplying gas molecules of ammonia and hydrogen into the first space 12 from an admission port 19, heating them at 1,800°C with a heating element 20 made from tungsten to catalytically decompose the molecules, and surface-treating the film 23 with the activated species; and supplying ammonia and silane into the second space 13, catalytically decomposing them with a heating element 52, and forming the gas barrier film of silicon nitride on the surface of the above surface-treated film 23 by a catalytic chemical vapor-deposition process. The catalytic chemical vapor-deposition process in the second space 13 may be replaced by a sputtering process, a plasma chemical vapor deposition process or the like, in order to form the gas barrier film. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
[Industrial applications]
The present invention relates to a method for forming a thin film on a plastic material and a plastic film material, which is flat and has a gas barrier function, particularly for oxygen and water vapor.
[0002]
[Prior art]
A gas barrier sheet used for packaging food and drink, pharmaceuticals, chemicals, daily necessities, miscellaneous goods, and various articles is formed by coating a gas barrier film on a plastic film. Conventionally, in particular, in order to prevent the deterioration of the contents and to allow foreign substances in the contents to be confirmed visually or with a metal detector, etc., particularly, oxygen and water vapor are cut off, and various transparent materials are used. Gas barrier films have been proposed and developed. Examples of the gas barrier film made of an inorganic material for such a purpose include an electron beam evaporation method, a sputtering method, and a plasma CVD (Chemical Vapor (CVD)).
A silicon oxide film or an aluminum oxide film formed by a method (which is an abbreviation of Deposition and is sometimes referred to as chemical vapor deposition or chemical vapor deposition) is generally used.
[0003]
In recent years, with respect to displays using organic electroluminescence (EL), liquid crystal, or the like, a configuration using a plastic thin plate or a plastic film as a substrate has been proposed from the viewpoint of weight reduction and thinning, and flexibility. For this plastic substrate, a gas barrier film that is transparent and has high barrier properties against oxygen and water vapor from the viewpoint of maintaining the visibility of the display unit and preventing the element unit formed on the substrate surface from being oxidized and deteriorated. Need to be coated. A configuration in which a silicon nitride film or a silicon oxynitride film is coated by a sputtering method or a CVD method as a high performance gas barrier film of an inorganic material for such a purpose has been proposed.
[0004]
Among them, regarding the formation of a silicon nitride film, for example, silane (SiH) is applied to a heating element made of a tungsten wire heated to about 1600 to 1800 ° C. ₄ ) Gas and ammonia (NH ₃ A) A chemical vapor deposition method (that is, a catalytic CVD (Cat CVD) method or a CVD method such as a Hot Wire CVD method) for depositing a silicon nitride film on a substrate by supplying a gas as a source gas to activate the decomposition. Recently, attention has been paid to one method for forming a gas barrier film that is transparent and has a barrier property against oxygen and water vapor.
[0005]
In the prior art having a gas barrier film of an inorganic material, particularly a silicon nitride film which is a hard material, if the film thickness is increased in order to improve the gas barrier performance, the film is cracked when the substrate is curved, and thus the gas barrier There is a problem that performance is reduced. Therefore, desirably, in a thin film having a thickness of 100 nm or less, the film needs to be densified to improve the gas barrier performance.
[0006]
In the case of a plastic substrate having low heat resistance, the film must be formed at a low substrate temperature. When the plastic substrate is, for example, polyethylene terephthalate (PET) resin, the film must be formed without exceeding the glass transition temperature. Requires that the substrate temperature be about 80 ° C. or less. According to the above-mentioned prior art, when a film is grown at such a low temperature, the surface movement distance of the film-forming species flying on the substrate surface is short, and the film-forming species is generally formed on the plastic substrate surface. Since there are few sites where the film is trapped, island-like film growth with a low density occurs when the film thickness is small. For this reason, in order to obtain sufficient gas barrier performance, the film must be grown to a thickness that combines these island-like films into a uniform film. It is necessary to increase the film thickness, and as a result, the film is easily broken as described above.
[0007]
In addition, regarding the gas barrier film for a plastic substrate used for a display as described above, particularly when an organic EL element is formed, since the thickness of the light emitting layer is very thin, about 100 nm, the film thickness non-uniformity of the light emitting layer and the electrode protrusions are reduced. In order to prevent the electric field concentration in the above, the gas barrier film serving as a base layer is required to have a flat surface. In response to this requirement, in the case where a low-density island-like film is grown in the above-described prior art, if the film thickness is increased until the desired gas barrier performance is exhibited, the undulation of the island-like film increases, so that the surface of the surface increases. There is a problem that flatness is impaired.
[0008]
[Problems to be solved by the invention]
An object of the present invention is to provide a film forming method, a film forming apparatus, and a gas barrier sheet which have surface flatness and can have a gas barrier function at a small film thickness.
[0009]
[Means for Solving the Problems]
In the present specification, the term “substrate” is an object on which a gas barrier film is to be formed, and may be a film having a thickness of, for example, 10 to 500 μm, or may be thicker than the film and less than 5 mm, for example. May be a plate-like body having a relatively large thickness, may have flexibility, may be rigid, may have another shape, and at least a part of the surface An object on which a gas barrier film is to be formed. This substrate is made of a synthetic resin.
[0010]
The present invention relates to a method of forming a gas barrier film on a plastic substrate,
Before forming the gas barrier film,
A method of forming a gas barrier film, wherein a surface treatment of the surface is performed by bringing a surface of the substrate into contact with an active species generated by catalytic decomposition of a gas molecule with a heating element.
[0011]
Further, the present invention, the gas molecules used in the surface treatment before forming the gas barrier film,
It is a gas molecule containing at least one of a hydrogen atom and a nitrogen atom.
[0012]
Further, the present invention is characterized in that a gas containing at least one of a hydrogen atom and a nitrogen atom used for surface treatment before forming a gas barrier film is hydrogen, ammonia, or a mixed gas of hydrogen and ammonia. .
[0013]
Further, the present invention is characterized in that the gas barrier film on the substrate is formed by a chemical vapor deposition method in which gas molecules are decomposed and activated by a heating element to form a film on the substrate.
[0014]
According to the present invention, by exposing the active species of the gas molecules to the surface of the plastic substrate, the chemical bonding state of the outermost surface of the substrate is changed, whereby the film formed on the substrate surface flies. The sites on the surface of the substrate where the species are captured are increased. Therefore, in the early stage of the subsequent formation of the gas barrier film, the density of the island-like film increases. Thereby, at a relatively thin film thickness, the island-like film is combined to exhibit a gas barrier function, and a film having surface flatness is obtained.
[0015]
Examples of the plastic substrate used in the present invention include polyethylene, polypropylene, polystyrene, polyethylene terephthalate, polysulfone, polyethersulfone, polyester, polymethyl methacrylate, polycarbonate, polyarylate, polyacetate, polyamide, and poly-4. -Any resin having transparency such as methylpentene-1, cellulose, polyvinyl chloride, polyacrylonitrile-based resin, phenoxy resin, polyphenylene oxide-based resin may be used, but may not have transparency.
[0016]
The thickness of the gas barrier film in the present invention is preferably from 5 to 200 nm, and most preferably from 20 to 100 nm, so as not to cause damage such as cracks when bending or bending.
[0017]
The gas used for the surface treatment of the plastic substrate in the present invention may be any gas that can be decomposed and activated by the heating element, and is determined by the heating element material, the temperature of the heating element and the reactivity of the gas. Preferably, a metal is used for the heating element, and from the viewpoint of the life of the heating element, non-oxidizing, expensive gold or platinum is used as the heating element except for the case where the heating element is expensive. It is preferable to use an oxidizing gas.
[0018]
Further, as shown in gas barrier film forming apparatuses 28 and 29 in FIGS. 1 and 2 described later, a film forming gas which is a raw material gas for forming a gas barrier film has a property of reacting with an oxidizing gas and has a surface property. When the space for the treatment and the space for forming the gas barrier film are in the same vacuum vessel, it is desirable to use a non-oxidizing (non-combustion) gas as the surface treatment gas from the viewpoint of safety. For these reasons, as the gas used for the surface treatment, a gas containing a hydrogen atom or a nitrogen atom is preferable. For example, hydrogen, ammonia, hydrazine and the like can be used, but hydrogen and ammonia are preferable because they are easy to handle. Further, the use of a mixed gas of hydrogen and ammonia does not hinder the present invention.
[0019]
Further, as a method of forming a gas barrier film in the present invention, any method of sputtering, plasma CVD, or catalytic CVD, which does not hinder the present invention, does not hinder the present invention, as a transparent gas barrier film, For example, an aluminum oxide film, a silicon oxide film, a silicon oxynitride film, a silicon nitride film, or the like can be used. The gas barrier film and the plastic substrate may have transparency, but may not have transparency, and may be light-shielding, for example.
[0020]
Using a catalytic chemical vapor deposition method of forming a film on a substrate by decomposing and activating gas molecules by a heating element as a gas barrier film forming method is the same as the surface treatment method of the present invention and the gas barrier film forming method. It is suitable in that it can be performed continuously in a vacuum vessel. As the gas barrier film using the catalytic chemical vapor deposition method, from the viewpoint of the life of the heating element, it is desirable to form the film in a reducing atmosphere. Therefore, a gas containing silicon atoms and a gas containing nitrogen atoms are formed as source gases. A silicon nitride film is preferred. Silane or disilane can be used as a gas containing silicon atoms, and ammonia or hydrazine can be used as a gas containing nitrogen atoms.Silane as a gas containing silicon atoms and ammonia as a gas containing nitrogen atoms can be used. It is preferred to use a combination with Alternatively, the gas containing silicon atoms and the gas containing nitrogen atoms may be diluted with hydrogen.
[0021]
Further, during the formation of the silicon nitride film, the moisture contained in the plastic base material is degassed, so that oxygen is taken into the film, which may result in a silicon oxynitride film. It does not hinder.
[0022]
Further, by using a hydrocarbon gas such as methylsilane, dimethylsilane or trimethylsilane, or methane or acetylene as a source gas, a silicon carbonitride film or a silicon oxynitride film does not hinder the present invention at all. Not something.
[0023]
Furthermore, according to this surface treatment method, moisture and oils and fats adsorbed on the surface of the plastic substrate are decomposed and desorbed by active species, or by selecting appropriate conditions, by radiant heat from the heating element, Degassing of moisture and the like contained in the substrate can be performed before forming the gas barrier film, which prevents deterioration of film quality due to contamination of the gas barrier film by impurities and improves production stability, which is a preferable mode.
[0024]
Further, the present invention provides a vacuum vessel having a first space for surface treatment and a second space for forming a gas barrier film,
Transport means for stretching and transporting a long plastic substrate from the first space to the second space;
An inlet means having a first inlet opening to the first space;
A gas for surface treatment which supplies the substrate surface treatment gas to the inlet means,
A heating element that is provided between the inlet and the base material in the first space, generates active species by catalytically decomposing a surface treatment gas, and performs surface treatment on the surface of the base material;
A gas barrier film forming apparatus provided in a second space, the thin film forming means forming a gas barrier film on the surface of the base material.
[0025]
Further, the invention is characterized in that the thin film forming means forms the gas barrier film by a sputtering method, a plasma CVD method, or a catalytic chemical vapor deposition method.
[0026]
Further, the present invention provides a vacuum vessel having a first space for surface treatment and a second space for forming a gas barrier film,
Transport means for stretching and transporting a long plastic substrate from the first space to the second space;
First inlet means having a first inlet opening to the first space;
A gas for surface treatment for supplying the gas for surface treatment of the base material to a first inlet means,
A first heating element that is provided between the first inlet and the substrate in the first space, generates a reactive species by catalytically decomposing a surface treatment gas, and surface-treats the surface of the substrate;
A second inlet means having a second inlet opening to the second space;
A source gas source for supplying a source gas for forming a gas barrier film to the second inlet means;
A gas barrier film is formed by catalytic decomposition with a source gas on the surface of the surface-treated substrate provided between the second inlet and the substrate in the second space, and the gas barrier film is formed by catalytic chemical vapor deposition. And a second heating element.
[0027]
Further, according to the present invention, the transport means includes:
A guide surface having a guide drum facing over the first and second spaces in the vacuum vessel;
The substrate is guided by being wound around a guide surface of a guide drum.
[0028]
Further, the present invention is characterized in that the surface treatment gas is a gas molecule containing at least one of a hydrogen atom and a nitrogen atom.
[0029]
According to the present invention, when a plastic film is used as a base material as shown in FIG. 1 described later, for example, a roll-shaped film is transferred from a first space for surface treatment in a vacuum vessel by a conveying means to form a gas barrier film. , And stretched and transported to the second space in this order, and a gas barrier film can be formed on the surface of the film by a roll-to-roll method. The gas barrier film formed in the second space may be formed by a plasma CVD method or a catalytic CVD method, but may be formed by another method, for example, a method such as a sputtering method or an evaporation method. In this way, a gas barrier film can be formed on the surface of a long continuous plastic film that has been subjected to the surface treatment as the film moves, so that a low-cost, high-quality gas barrier film can be formed.
[0030]
In the second space, it is preferable to form a gas barrier film by a catalytic CVD method from the viewpoint of simplifying the process.
[0031]
Since the first and second spaces cannot be completely blocked, the gas for surface treatment of the plastic film uses a part of the gas type used for forming the gas barrier film or a gas that does not affect the gas barrier film formation. It is desirable. For example, in the case where a silicon nitride film is formed using a source gas such as a silane gas or an ammonia gas for a gas barrier film, an ammonia gas, a hydrogen gas, or a mixed gas thereof can be used as a gas used for surface treatment. .
[0032]
By wrapping a plastic film around, for example, a guide surface of a straight cylindrical guide drum, the film can be surface-treated in a stable posture and a gas barrier film can be formed.
[0033]
The invention also provides a vacuum vessel,
Inlet means having an inlet open to the space in the vacuum vessel,
A surface treatment gas source for supplying a surface treatment gas for the plastic base material,
Control means for supplying the surface treatment gas from the surface treatment gas source to the inlet means,
A heating element provided between the inlet and the base material in the space to generate active species by catalytically decomposing a surface treatment gas, and surface-treat the surface of the base material,
An apparatus for forming a gas barrier film, comprising: a thin film forming means for forming a gas barrier film in the space on the surface of the surface-treated base material.
[0034]
The invention also provides a vacuum vessel,
Inlet means having an inlet open to the space in the vacuum vessel,
A surface treatment gas source for supplying a surface treatment gas for the plastic base material,
A source gas source for supplying a source gas for forming a gas barrier film,
Control means for switching the surface treatment gas from the surface treatment gas source and the source gas from the source gas source in this order to supply the source gas to the inlet means;
The space is provided between the inlet and the substrate, the surface treatment gas is catalytically decomposed to generate active species, the surface of the substrate is surface-treated, and the surface-treated substrate is An apparatus for forming a gas barrier film, characterized by including a heating element on its surface that generates an active species by catalytic decomposition with a raw material gas and catalytically vapor-deposits a gas barrier film.
[0035]
According to the present invention, as shown in FIGS. 2 to 4 described later, the gas barrier film is formed by, for example, a catalytic chemical vapor deposition method in which gas molecules are decomposed and activated by a heating element to form a film on a substrate. In this case, since the surface treatment of the present invention and the formation of the gas barrier film can be performed in the same space of one vacuum vessel, the apparatus is simplified and more preferable.
[0036]
Also, the present invention includes an openable and closable shielding member disposed between the base material and the heating element in the space,
The control means is characterized in that the heat shielding member is temporarily closed at an initial stage of the supply of the surface treatment gas to the space and at the time of switching the supply from the surface treatment gas to the source gas.
[0037]
According to the present invention, after performing the surface treatment of the plastic base material, when switching the supply from the surface treatment gas to the raw material gas to form a gas barrier film, between the base material and the heating element The disposed shielding member is temporarily closed. This stabilizes the surface treatment gas or raw material gas in the space, and makes the flow state and concentration distribution uniform in the space. Therefore, surface treatment and formation of a gas barrier film can be achieved with high quality.
[0038]
The present invention also provides a plastic film having a surface treated with active species generated by catalytic decomposition of a gas molecule with a heating element,
A gas barrier film formed on the surface of the film.
[0039]
Further, the invention is characterized in that the gas barrier film has a thickness of 5 to 200 nm.
[0040]
According to the present invention, the gas barrier sheet can be realized by forming a gas barrier film through which a gas such as oxygen or water vapor does not easily pass on the surface of the plastic film having the above-mentioned surface-treated surface. The surface of the gas barrier film of such a gas barrier sheet is flat compared to the prior art in which the surface treatment of the present invention is not performed. In addition, since the gas barrier film can be formed with a uniform thickness over the entire surface where the gas barrier film of the film is to be formed, the thickness of the gas barrier film can be reduced, for example, 5 to 200 nm as described above. And more preferably 20 to 100 nm. As a result, even if the gas barrier film is made of a material having a relatively fragile property, such as a hard material such as silicon nitride, it is possible to prevent the gas barrier sheet from being damaged such as cracks when the gas barrier sheet is bent or bent. As a result, the gas barrier function can be reliably achieved.
[0041]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 is a cross-sectional view schematically showing the entire configuration of a gas barrier film forming apparatus 28 according to an embodiment of the present invention. In the gas barrier film forming apparatus 28, the vacuum vessel 11 and the film 23, which is a long plastic base material, are wound around a straight cylindrical guide drum 51 through passages 55 formed in partition members 53 and 54. The film 23 is fed from the supply roll 22 to the guide drum 51 in the supply direction 57 via the supply roll 56, and the film 23 from the guide drum 51 is guided by the take-up roll 58, conveyed in the take-up direction 59, and wound. It is wound on a take-up roll 61. The film 23 is continuously stretched and transported by the transport means 62 by a roll-to-roll method.
[0042]
In the vacuum vessel 11 below the partition members 53 and 54 in FIG. 1, the partition member 14 partitions the surface into a first space 12 for surface treatment and a second space 13 for forming a gas barrier film. Is transported from the first space 12 to the second space 13.
[0043]
The first space 12 is provided with a first inlet 64. The first inlet means 64 has a first inlet 19 which opens to the first space 12 and faces the guide drum 51. The first inlet means 64 is supplied with a surface treatment gas for the film 23 from a surface treatment gas source 65. The first heating element 20 is disposed in the first space 12 between the first introduction port 19 and the film 23 wound around the guide drum 51. The first heating element 20 catalytically decomposes the surface treatment gas from the first inlet 19 to generate active species, and the active species treats the surface of the film 23 in the first space 12 with the active species. The heating element 20 is made of a metal such as linear tungsten, and generates heat when supplied with power from a power supply 21.
[0044]
Heating element 20 is made of a high melting point metal, and for example, tungsten having excellent heat resistance is preferable. The temperature of the heating element 20 used for the surface treatment of the film 23 needs to have a temperature at which the surface treatment gas from the gas source 65 efficiently contacts and decomposes. In a configuration in which the heating element 20 is made of tungsten and a hydrogen gas is used as the surface treatment gas, the temperature of the heating element 20 is selected to be 1000 ° C. or higher. In the configuration using ammonia gas as the surface treatment gas, the temperature of the heating element 20 is selected to be 1200 ° C. or higher. The surface treatment gas may be a mixed gas of a hydrogen gas and an ammonia gas. In this case, the heating element 20 is selected to have a temperature of 1200 ° C. or higher. The heating element 20 has a temperature of less than 2000 ° C. at which tungsten does not evaporate, thereby preventing the surface of the film 23 from being contaminated with tungsten.
[0045]
In the second space 13, a gas barrier film is formed on the surface-treated surface of the film 23 wound around the guide drum 51 by, for example, a catalytic chemical vapor deposition method. For catalytic chemical vapor deposition, a second inlet means 67 having a second inlet 17 open to the second space 13 is provided, in which a gas barrier film is formed from a gas source 18. Raw material gas is supplied. The second heating element 52 is disposed in the second space 13 between the second inlet 17 and the film 23 guided by the guide drum 51, and is supplied with power from a power supply 68. The second heating element 52 catalytically decomposes the raw material gas from the second inlet 17 to generate active species, and performs catalytic chemical vapor deposition of a gas barrier film on the surface of the surface-treated film 23. The second heating element 52 has a configuration similar to that of the first heating element 20 described above. When the heating element 52 is made of tungsten and a silicon nitride film is formed as a gas barrier film, the source gases supplied from the gas source 18 are a silane gas and an ammonia gas. The temperature of the heating element 52 is selected to be 1600 ° C. or higher in order to prevent the deterioration of the heating element 52 due to the formation of a mixture of tungsten and silicon, and is selected to be less than 2000 ° C. at which tungsten does not evaporate. Such a configuration in which the gas barrier film is formed by the catalytic chemical vapor deposition method is preferable because the process is simplified.
[0046]
Since the first and second spaces 12 and 13 cannot be completely blocked by the partition member 14, the surface treatment gas used in the first space 12 may be a part of the gas type used for forming the gas barrier film, or a gas barrier. It is preferable to use a gas that does not adversely affect the formation of the film, and when using a silane gas and an ammonia gas as a source gas to form a silicon nitride film as a gas barrier film as described above, as described above as a surface treatment gas It is preferable to use ammonia gas, hydrogen gas, or a mixed gas thereof. In one embodiment, since the film 23 moves at a speed of 0.1 to 10 m / sec, when the area of the space 12 parallel to the moving direction of the film 23 is, for example, 1 m, the processing time is 0.1. About 10 seconds. In order to effectively perform the surface treatment in such a short time, it is desirable to use not only the heating effect from the heating element 20 but also the method of exposing the chemically active species described in the present invention. By disposing the space 12 in the continuous film forming apparatus 28, it is possible to form a low-cost and high-quality gas barrier film by continuously performing surface treatment and gas barrier film formation.
[0047]
The interior of the vacuum vessel 11 including the first and second spaces 12 and 13 is, for example, 2 × 10 ^-4 It is evacuated to Pa or less.
[0048]
Regarding the temperature of the heating elements 20 and 52, in order to reduce thermal damage to the film 23, which is a plastic substrate having low heat resistance, the above-mentioned surface treatment gas is efficiently decomposed, It is desirable that the temperature be equal to or higher than the temperature at which the reaction deterioration with the metal is prevented, and the temperature be as low as possible.However, in actuality, depending on the surface treatment effect, the gas barrier film characteristics, the gas barrier film growth rate, and the degree of substrate damage, the processing time and It is optimized according to the film formation time. Cooling the substrate in order to reduce damage to the plastic substrate having low heat resistance does not hinder the present invention at all, but is preferable.
[0049]
In another embodiment of the present invention, a gas barrier film may be formed in the second space 13 by a sputtering method, a plasma chemical vapor deposition method, or another method.
[0050]
FIG. 2 is a cross-sectional view of the gas barrier film forming apparatus 29 according to the embodiment of the present invention in which the entire configuration is simplified. In the gas barrier film forming apparatus 29, the surface of the plastic film 39 held in the space 44 of the vacuum vessel 31 facing downward in FIG. 2 is catalytically decomposed by activating hydrogen and ammonia gas molecules by the heating element 34. The active species are contacted to perform a surface treatment, and then a gas barrier film is deposited and formed on the surface-treated surface by a catalytic CVD method using an ammonia gas and a silane gas. In the catalytic CVD method for the gas barrier film, the silane gas is catalytically decomposed by the heating element 34, and a gas barrier film is formed by the active species generated by this.
[0051]
In a space 44 in the vacuum vessel 31, an inlet means 45 having an inlet 35 is arranged. The introduction port 35 is open to the space 44 upward in FIG. Above the space 44, a film 39 which is a plastic substrate is held by a holding mechanism acting as a substrate holder, and the cooling mechanism 33 should form a gas barrier film of the film 39 by a coolant from a cooling source 46. It cools by contacting the surface opposite to the surface (ie, the upper surface in FIG. 2).
[0052]
A shielding member 42, which is an openable and closable shutter that partitions a space 44, is provided between the film 39 and the heating element 34 in the vacuum container 31, and is driven to be opened and closed by a driving unit 43. A gas source 36 for a hydrogen gas, a gas source 37 for an ammonia gas, and a gas source 38 for a silane gas are connected to the inlet 45 via on-off valves V36, V37, and V38, respectively. Hydrogen gas and ammonia gas from the gas sources 36 and 37 are used as surface treatment gases, and ammonia gas and silane gas from the gas sources 37 and 38 are used as source gases for the gas barrier film. The configuration of the heating means 34 is the same as the configuration of the heating elements 20 and 52 in the embodiment of FIG. 1 described above, and the power from the power supply 47 is supplied.
[0053]
FIG. 3 is a block diagram showing an electrical configuration in the embodiment of FIG. An input means 72 for performing an input operation by an operator is connected to a processing circuit 71 realized by a microcomputer or the like, whereby the processing circuit 71 automatically performs the surface treatment of the film 39 and the formation of the gas barrier film. In order to perform the operation continuously, the driving means 43 for the shielding member 42 and the opening / closing valves V36, V37, and V38 are controlled, and the heating element 34 is kept at, for example, 1800 ° C. by the power supply 47, and the space 44 is exhausted by the exhaust pump 41. To 2 × 10 ^-4 The vacuum is maintained at a pressure of Pa or less.
[0054]
FIG. 4 is a timing chart for explaining the operation of the processing circuit 71. The temperature of the heating element 34 is maintained at 1800 ° C. by the power supply 47 as described above. In FIG. 4A showing the opening / closing operation of the shielding member 42 by the driving means 43, at time t1 before time t2, the opening / closing valve V36 is turned on as shown in FIG. Further, the on-off valve V37 is opened as shown in FIG. 4 (3), and hydrogen gas and ammonia gas are supplied. At time t2 when the hydrogen and ammonia gases are supplied to the space 44 at a stable flow rate and a uniform distribution, the driving unit 43 opens the shielding member 42. As a result, the active species catalytically decomposed by the heating element 34 of hydrogen and ammonia gas come into contact with the surface of the film 39 to perform a surface treatment. In this way, at the initial stage of the surface treatment at times t1 to t2 before time t2, the state of the surface treatment gas in the space 44 is stabilized because the shielding member 42 is closed.
[0055]
At time t3 when the surface treatment ends, the shielding member 42 is temporarily closed. After this time t3, the on-off valve V36 shown in FIG. 4B is closed to form the gas barrier film by the catalytic chemical vapor deposition method. By opening the on-off valve V38 shown in FIG. 4D, the ammonia gas, the silane gas and the hydrogen are supplied to the space 44. After the time t4 when the ammonia gas and the silane gas are stabilized at a stable flow rate and a uniform concentration in the space 44, the shielding member 42 is opened. As a result, a silicon nitride film as a gas barrier film is formed on the surface of the film 39 that has been subjected to the surface treatment by the active species resulting from the catalytic decomposition of the ammonia gas and the silane gas by the heating element 34. At time t5 after the formation of the gas barrier film, the shielding member 42 is closed, and the on-off valves V37 and V38 are closed, thus ending a series of operations.
[0056]
When a plate-shaped substrate is used as a gas barrier film forming apparatus according to another embodiment of the present invention, for example, a load lock chamber, a substrate surface pretreatment chamber of the present invention, and a deposition method of vapor deposition, sputtering, or CVD The gas barrier film deposition chamber having the above mechanism is connected to the robot arm chamber by a gate valve, and a so-called single-wafer type apparatus configuration in which the robot arm moves back and forth between the rooms is possible.
[0057]
【Example】
Hereinafter, examples of the present invention will be described.
[0058]
In a device as shown in FIGS. 2 to 4, a polyethylene terephthalate (PET) film 39 having a thickness of 125 μm is brought into close contact with a holding mechanism 32 as a substrate holder, and is placed in a vacuum vessel 31. Vacuum container 31 to 2 × 10 ^-4 The evacuation was performed to Pa or less, and then the holding mechanism 32 as a substrate holder was cooled to −20 ° C.
[0059]
In a state where the temperature of the holding mechanism 32 and thus the film 39 is maintained at −20 ° C., a hydrogen gas and an ammonia gas are introduced into the vacuum vessel 31, and the gas introduction port 35 and the film 39 are introduced to decompose and activate the gas. Was heated to 1800 ° C.
[0060]
Subsequently, by opening a shutter 42 provided between the heating element 34 and the film 39, the surface of the film 39 was exposed to hydrogen gas and ammonia gas decomposing active species for 20 seconds. Thereafter, while the heating element 34 is maintained at 1800 ° C., the shutter 42 is closed once, a silane gas is introduced into the vacuum vessel 31, and then the shutter 42 is opened again, and the surface of the film 39 is nitrided to a thickness of 60 nm. The silicon film was formed by a catalytic CVD method.
[0061]
When the surface roughness of the film on which the silicon nitride film was formed was evaluated by an atomic force microscope (AFM), the surface roughness of the film 39 before the surface treatment was 1.7 nm, 0.0 nm.
[0062]
Further, when the oxygen gas permeability of the gas barrier sheet having a silicon nitride film formed on the film 39 was evaluated at a temperature of 23 ° C. and a relative humidity of 0% by a differential pressure method of Japanese Industrial Standard, 0.9 cc / m ² * Day * Pa.
[0063]
In addition, the same polyethylene terephthalate film was subjected to measurement by X-ray photoelectron spectroscopy XPS of the surface to be treated of the film which had been subjected to the same surface treatment as described above, and was compared with the surface of the film which had not been subjected to the surface treatment. As shown in FIG. 5, nitrogen N1s is detected on the film surface, and from the spectrum of C1s shown in FIG. 6, the bonding state of carbon and hydrogen or oxygen on the surface is CH, CO by surface treatment. , C = O changed. Thus, according to the present invention, it was confirmed that the surface of the film 39 was modified.
[0064]
[Comparative example]
In the apparatus as shown in FIG. 2, the polyethylene terephthalate film 39 is attached to the holding mechanism 32 in the same manner as described above, and is placed in the vacuum vessel 31. ^-4 The evacuation was performed to Pa or less, and then the holding mechanism 32 was cooled to −20 ° C.
[0065]
While maintaining the temperature of the holding mechanism 32 at −20 ° C., while the shutter 42 is closed, the silane gas, the hydrogen gas, and the ammonia gas are placed in a vacuum container so that the flow rate and the pressure become the same as the film forming conditions of the above-described embodiment. The linear heating element 34 made of tungsten and disposed between the gas introduction port 35 and the film 39 was heated to 1800 ° C. in order to introduce the gas into the inside 31 and activate the decomposition of the gas. Subsequently, the shutter 42 provided between the heating element 34 and the film 39 was opened to form a 60-nm-thick silicon nitride film on the surface of the film 39.
[0066]
When the surface roughness of the film on which the silicon nitride film was formed was evaluated by an atomic force microscope (AFM), the surface roughness of the film was 1.7 nm but 4.2 nm.
[0067]
The oxygen gas permeability of the sheet having the silicon nitride film formed on the film 39 was evaluated at a temperature of 23 ° C. and a relative humidity of 0% by a differential pressure method according to Japanese Industrial Standards. ² * Day * Pa. Therefore, in the above-described embodiment of the present invention, the surface roughness of the silicon nitride film is smaller and flatter than that of the comparative example, and in the embodiment of the present invention, the oxygen gas permeability is smaller than that of the comparative example, It was confirmed that the performance was improved.
[0068]
【The invention's effect】
As apparent from the above description, according to the present invention, for example, a method of forming a gas barrier film on a plastic substrate by a catalytic chemical vapor deposition method in which a film is deposited by radicals generated by thermal catalytic decomposition with a heating element, and In the apparatus, before the film is deposited, the surface of the substrate is subjected to a surface treatment with an active species generated by catalytic decomposition of a gas containing at least one of hydrogen atoms and nitrogen atoms with a heating element to perform surface modification. Thereby, a film having high surface flatness and high gas barrier performance can be formed.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view schematically showing the entire configuration of a gas barrier film forming apparatus according to an embodiment of the present invention.
FIG. 2 is a simplified cross-sectional view of the overall configuration of a gas barrier film forming apparatus 29 according to an embodiment of the present invention.
FIG. 3 is a block diagram showing an electrical configuration in the embodiment of FIG.
FIG. 4 is a timing chart for explaining the operation of the processing circuit 71.
FIG. 5 is a diagram showing a measurement result of the present inventor by X-ray photoelectron spectroscopy.
FIG. 6 is a diagram showing another measurement result by X-ray photoelectron spectroscopy of the present inventor.
[Explanation of symbols]
11,31 Vacuum container
12 First space
13 Second space
17 Second Inlet
18 Source gas source
20 First heating element
23,39 plastic film
28,29 Gas barrier film forming equipment
32 Holding mechanism
34 Heating element
35 Inlet
36 Hydrogen gas source
37 Ammonia gas source
38 Silane gas source
42 Shielding member
43 Driving means
44 Space
45 Inlet means
51 Guide drum
52 Second heating element
62 Conveying means
65 Surface treatment gas source
67 Second inlet means
V36, V37, V38 On-off valve

Claims (14)

In a method of forming a gas barrier film on a plastic substrate,
Before forming the gas barrier film,
A method of forming a gas barrier film, wherein a surface treatment of the surface is performed by bringing a surface of the base material into contact with an active species generated by catalytic decomposition of a gas molecule with a heating element. Gas molecules used for surface treatment before forming a gas barrier film,
2. The gas barrier film forming method according to claim 1, wherein the gas molecule contains at least one of a hydrogen atom and a nitrogen atom. 3. The gas according to claim 2, wherein the gas containing at least one of a hydrogen atom and a nitrogen atom used for the surface treatment before forming the gas barrier film is hydrogen, ammonia, or a mixed gas of hydrogen and ammonia. Gas barrier film forming method. The gas barrier film on the base material is formed by a chemical vapor deposition method in which gas molecules are decomposed and activated by a heating element to form a film on the base material. Gas barrier film forming method. A vacuum vessel having a first space for surface treatment and a second space for forming a gas barrier film;
Transport means for stretching and transporting a long plastic substrate from the first space to the second space;
An inlet means having a first inlet opening to the first space;
A gas for surface treatment which supplies the substrate surface treatment gas to the inlet means,
A heating element that is provided between the inlet and the base material in the first space, generates active species by catalytically decomposing a surface treatment gas, and performs surface treatment on the surface of the base material;
A thin film forming means provided in the second space for forming a gas barrier film on the surface of the substrate. A vacuum vessel,
Inlet means having an inlet open to the space in the vacuum vessel,
A surface treatment gas source for supplying a surface treatment gas for the plastic base material,
A control means for supplying a surface treatment gas from a surface treatment gas source to an inlet means, provided between the inlet and the substrate in the space, and catalytically decomposing the surface treatment gas to form active species A heating element that is generated and surface-treats the surface of the substrate,
A gas barrier film forming apparatus, comprising: a thin film forming means for forming a gas barrier film in the space on the surface of the surface-treated base material. 7. The gas barrier film forming apparatus according to claim 5, wherein the thin film forming means forms the gas barrier film by a sputtering method, a plasma CVD method, or a catalytic chemical vapor deposition method. A vacuum vessel having a first space for surface treatment and a second space for forming a gas barrier film;
Transport means for stretching and transporting a long plastic substrate from the first space to the second space;
First inlet means having a first inlet opening to the first space;
A gas for surface treatment for supplying the gas for surface treatment of the base material to a first inlet means,
A first heating element that is provided between the first inlet and the substrate in the first space, generates a reactive species by catalytically decomposing a surface treatment gas, and surface-treats the surface of the substrate;
A second inlet means having a second inlet opening to the second space;
A source gas source for supplying a source gas for forming a gas barrier film to the second inlet means;
A gas barrier film is formed by catalytic decomposition with a source gas on the surface of the surface-treated substrate provided between the second inlet and the substrate in the second space, and the gas barrier film is formed by catalytic chemical vapor deposition. And a second heat generating element. The transport means is
A guide surface having a guide drum facing over the first and second spaces in the vacuum vessel;
The gas barrier film forming apparatus according to any one of claims 5 to 8, wherein the substrate is guided by being wound around a guide surface of a guide drum. A vacuum vessel,
Inlet means having an inlet open to the space in the vacuum vessel,
A surface treatment gas source for supplying a surface treatment gas for the plastic base material,
A source gas source for supplying a source gas for forming a gas barrier film,
Control means for switching the surface treatment gas from the surface treatment gas source and the source gas from the source gas source in this order to supply the source gas to the inlet means;
The space is provided between the inlet and the substrate, the surface treatment gas is catalytically decomposed to generate active species, the surface of the substrate is surface-treated, and the surface-treated substrate is An apparatus for forming a gas barrier film, comprising: a heating element that generates active species by catalytic decomposition with a source gas and catalytically vapor-deposits a gas barrier film on a surface thereof. Including an openable and closable shielding member disposed between the base material and the heating element in the space,
The gas barrier according to claim 10, wherein the control unit temporarily closes the heat shielding member at an initial stage of supply of the surface treatment gas to the space and at the time of switching the supply from the surface treatment gas to the source gas. Film forming equipment. The gas barrier film forming apparatus according to any one of claims 5 to 11, wherein the surface treatment gas is a gas molecule containing at least one of a hydrogen atom and a nitrogen atom. A plastic film whose surface is surface-treated with active species generated by catalytic decomposition of gas molecules with a heating element,
A gas barrier film formed on the surface of the film. The gas barrier sheet according to claim 13, wherein the gas barrier film has a thickness of 5 to 200 nm.

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