JP5504720B2 - Deposition equipment - Google Patents

Description

  The present invention relates to an apparatus for producing a thin film laminate on a substrate. The present invention also relates to an oxygen and water vapor barrier laminate produced using this apparatus, a gas barrier filter using the same, and an optical member such as an optical filter and an optical functional filter.

  In recent years, with regard to electronic paper, organic EL, and LCDs that are widely used as next-generation FPDs, in order to achieve flexibility in these FPDs, or to reduce weight, reduce costs, break glass substrates, etc. There is an increasing demand to replace the glass substrate with a plastic film in order to improve throughput during production. Organic EL is also attracting attention as an alternative illumination method to replace fluorescent lamps. In this case, it is required to use a plastic film for reasons such as weight saving and ensuring safety. On the other hand, apart from making FPD flexible, industrial materials such as solar cell backsheets are often used from the viewpoints of weight reduction, thickness reduction, damage prevention, and the like.

The glass substrate has a gas barrier property required to suppress deterioration of internal elements due to oxygen and water vapor derived from the environment. However, gas barrier films for flexible packaging materials have not reached the barrier level, and industrial materials such as solar battery back sheets to which plastic films can be applied are several times more than barrier films for food packaging materials, electronic paper, organic It is said that a water vapor barrier property of 10 ⁻² g / m ² / day or less is necessary for a display sealing film such as EL. Moreover, a solar cell and a thin film solar cell may be required to have a water vapor barrier property of 1 g / m ² / day or less and a higher barrier property depending on the type of the thin film.

In order to realize a plastic film having such a high gas barrier property, physical film formation methods (PVD methods) such as induction heating method, resistance heating method, electron beam vapor deposition method, sputtering method, etc., are required to increase the area and roll to two.・ Because it can be easily developed on rolls, it is being considered that high gas barrier properties can be expected using these methods. However, the PVD method is roughly divided into an evaporation method such as an induction heating method, a resistance heating method, and an electron beam evaporation method, and a sputtering method. The evaporation method is a dense film having a high gas barrier property although the film formation speed is high. On the other hand, the sputtering method has a slow film formation speed, but it is possible to obtain a dense film having a high gas barrier property. For this reason, in general, gas barrier films for flexible packaging materials often use vapor deposition, and large-area film formation using sputtering is often used for optical film applications that require precise film thickness control. The price per m ² is higher than the vapor deposition method.

  Regarding the problem of incompatibility between the productivity and the gas barrier property, a pressure gradient type plasma gun is used as a material evaporation method as a means of taking the productivity between the vapor deposition method and the sputtering method and the gas barrier property between the vapor deposition method and the sputtering method. The vapor deposition method used as the above has been devised (Patent Document 1). In this method, the plasma emitted from the plasma gun is focused to the material using a magnetic field, etc., and the material is heated and evaporated. At the same time, the atoms and molecules being evaporated pass through the plasma emitted from the plasma gun. In this way, it is activated and can enter a substrate with a higher kinetic energy than that during evaporation, whereby a denser film can be obtained than a normal vapor deposition method.

JP 2005-34831 A

  However, this method is less complicated because the material can be evaporated and activated by plasma at the same time, and it is advantageous in terms of apparatus cost. On the other hand, the material evaporation rate and the plasma density are uniquely determined. There is a problem that the evaporation rate and the plasma density for activation cannot be determined freely. For this reason, there is a problem that it is difficult to freely set the gas barrier property with respect to the film formation rate.

  In view of the above problems, the present invention can freely set the evaporation rate and plasma density of the material, can freely set the gas barrier property with respect to the film formation rate, and has excellent oxygen barrier property and water vapor barrier property, or is transparent. Provided is a film forming apparatus capable of producing a translucent gas barrier laminate.

As means for solving the above-mentioned problems, the invention according to claim 1 is characterized in that a transport means for transporting the film base material in a roll-to-roll manner and a vapor deposition means for vapor-depositing a vapor deposition material on the film base material. a film forming apparatus comprising the deposition means, and means for evaporating the deposition material, the evaporated the vapor deposition material have a means for activating the plasma, a means for evaporating the deposition material, electronic The film forming apparatus is characterized by beam heating, wherein the electron beam used for the electron beam heating is a straight electron beam, and the means for activating the evaporated deposition material with plasma is a holocathode discharge .

  The invention described in claim 2 is characterized in that the vapor deposition means includes means for accelerating the evaporated vapor deposition material by an electric field and depositing it on the film substrate. Device.

The invention described in Claim 3 is the hollow cathode and the anode to be used in the hollow cathode discharge, the anode is a film-forming apparatus according to claim 1, characterized in that it is placed around the hollow cathode.

The invention according to claim 4, wherein the hollow cathode and the anode to be used in the hollow cathode discharge, according to claim 1, wherein the anode is characterized in that it is installed at a position facing the said hollow cathode across the deposition material The film forming apparatus.

According to a fifth aspect of the present invention, in the holocathode and the anode used for the holocathode discharge, the anode is installed around the holocathode and at a position facing the holocathode with the vapor deposition material interposed therebetween. The film forming apparatus according to claim 1 .

  According to the present invention, in the vapor deposition method, the evaporation rate of the material and the plasma density can be freely set independently, the gas barrier property with respect to the film forming rate can be freely set, and the oxygen barrier property and the water vapor barrier property are excellent. Alternatively, it is possible to provide a film forming apparatus capable of producing a translucent gas barrier laminate, and provide a gas barrier laminate and an optical member using the same.

It is the schematic diagram which showed one Embodiment of the film-forming apparatus of this invention. It is sectional drawing which showed one Embodiment of the holo cathode gun of this invention.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic view showing an embodiment of a film forming apparatus of the present invention. The film forming apparatus 30 includes a film forming chamber 10 and a take-up chamber 11, and includes a transport unit that transports the film base material in a roll-to-roll manner within the film forming apparatus. Means for transporting the film substrate in a roll-to-roll manner includes an unwinding roller 12, a winding roller 13, and a main roller 14. The film substrate 27 is unwound from the unwinding roller 12 and is wound around the winding roller 13 via the main roller 14. At this time, the vapor deposition material 16 is deposited on the film base material 27 by the main roller 14 to form a vapor deposition film.

  The film substrate 27 is not particularly limited, and a known one can be used. For example, polyolefin (polyethylene, polypropylene, etc.), polyester (polyethylene terephthalate, polyethylene naphthalate, etc.), polyamide (nylon-6, nylon-66, etc.), polystyrene, ethylene vinyl alcohol, polyvinyl chloride, polyimide, polyvinyl alcohol, Polycarbonate, polyethersulfone, acrylic, cellulose-based (triacetyl cellulose, diacetyl cellulose, etc.) and the like are exemplified, but not particularly limited. In practice, it is desirable to select appropriately depending on the application and required physical properties, but this is not a limited example, but polyethylene terephthalate, polypropylene, nylon, etc. are easy to use for packaging medical supplies, drugs, foods, etc. In addition, it is desirable to use a base material having high gas barrier properties such as polyethylene naphthalate, polyimides, and polyethersulfone for packaging that protects extremely moisture-insensitive contents such as electronic members and optical members. Moreover, although the base film thickness is not limited, about 6 to 200 μm is easy to use depending on the application.

  In addition, the film forming apparatus of the present invention includes means for evaporating the vapor deposition material 16 in order to deposit the vapor deposition material 16 on the film substrate 27. The vapor deposition material 16 is evaporated by filling the material filling type resistance heating crucible 15 with the vapor deposition material 16 and heating it. Further, a resistance heating DC power source 20 for heating the material filling type resistance heating crucible 15 is connected to the material filling resistance heating type crucible 15.

The vapor deposition material 16 is not particularly limited, and a known material can be used. Examples include, but are not limited to, magnesium oxide (MgO), indium-tin oxide (ITO), silicon oxide compounds such as silicon monoxide (SiO) and silicon dioxide (SiO ₂ ), or a mixture thereof. Alternatively, a metal material such as aluminum (Al) or silicon (Si) may be used. In particular, the vapor deposition material 16 of the present invention is a reactive vapor deposition of a silicon oxide compound, a silicon nitride compound, a silicon oxynitride compound, aluminum oxide, aluminum, and silicon, which are particularly excellent in transparency and barrier properties against oxygen and water vapor. Is preferred.

  When reactive vapor deposition is desired, a reactive gas can be allowed to flow from the gas pipe 23. When a metal material is used as the vapor deposition material 16, oxidation and nitridation can be performed. It is also possible to control the transparency when a ceramic material is used as the vapor deposition material 16.

  The material filling type resistance heating crucible 15 is filled with the vapor deposition material 16, but there is no problem even if a metal wire feed type is resistance heated. In this case, the type of the vapor deposition material 16 is limited to materials that can be made into wires, but it can be used as needed.

  Further, the film forming apparatus of the present invention includes means for activating the evaporated deposition material 16 with the plasma 29 in order to deposit the deposition material 16 on the film substrate 27. The evaporated vapor deposition material 16 is incident on the film substrate 27 held by the main roller 14 as the evaporated particles 28. At this time, the evaporated particles 28 are activated by passing through the plasma 29 before the evaporated particles 28 are incident on the film substrate 27.

  A holocathode gun 17 using a holocathode discharge is installed as a generation source of plasma 29 that activates the evaporated particles 28, and an internal electrode 18 or an external electrode 19 is installed as an anode. The holocathode gun 17 is connected to a holocathode discharge DC power supply 21 for generating a holocathode discharge.

  In the holocathode discharge, the electrons accelerated by the sheath voltage in the cylindrical holocathode move in the holocathode and decelerate by the sheath voltage of the holocathode. The decelerated electrons are accelerated by the sheath voltage again. The ionization is repeated by moving in the holocathode, and indicates high density plasma generated. In the system in which gas is introduced from the holocathode, a pressure gradient is generated between the film forming chamber 10 and the inside of the holocathode, and high-density plasma can be actively extracted to the film forming chamber 10 side.

  The internal electrode 18 is an anode for the holocathode, and is installed inside the holocathode gun 17 so as to generate a holocathode discharge inside the holocathode gun 17.

  FIG. 2 is a sectional view showing an embodiment of the holocathode gun 17 of the present invention. The holocathode gun 17 includes a holocathode 31 and an anode 32 positioned around the holocathode 31, and high-density plasma is generated inside the holocathode 31. The internal electrode 18 corresponds to the anode 32.

  When the internal electrode 18 is used as an anode, for example, plasma generated from the holocathode 17 using Ar gas diffuses in both directions, so that the plasma spreads over the entire deposition space. In this case, plasma having a relatively high density diffuses throughout the film forming chamber 10, and activation of the evaporated particles 28 including ionization is promoted, so that the ionized vapor deposition particles 28 and Ar ions are applied to the film base material 27. Increasing the electric field acceleration of the sheath and entering

  The position of the internal electrode 18 of the present invention is set so as to be positioned around the holocathode in the holocathode gun 17 as shown in FIGS. 1 and 2, but the plasma generated from the holocathode 17 spreads over the entire deposition space, As long as a relatively high density plasma can be spread uniformly, the present invention is not limited to the embodiment shown in FIGS. For example, the internal electrode 18 may be made independent from the holo cathode gun 17 and installed around the holo cathode gun 17.

  Moreover, since the discharge becomes unstable when the internal electrode 18 is contaminated by the vapor deposition material 16, a structure such as a cover may be provided so that the internal electrode 18 is hardly contaminated.

  On the other hand, the external electrode 19 is an anode for the holocathode, like the internal electrode 18, and may be positioned outside the holocathode gun 17. However, the position facing the holocathode gun 17 with the vapor deposition material 16 interposed therebetween as shown in FIG. It is preferable that it is installed in. The positional relationship between the holocathode and the external electrode 19 is not limited to the positional relationship as shown in FIG. 1 as long as the region where the plasma 29 is generated and the region where the evaporated particles 28 are present overlap.

  When the vapor deposition material 16 is an insulating material, the external electrode 19 is contaminated by the vapor deposition material 16 during vapor deposition. When the contamination progresses excessively, electrons do not flow, which causes problems such as arcing or inability to sustain discharge. To do. For this reason, when the vapor deposition material 16 is an insulating material, it is necessary to devise such as arranging an adhesion preventing plate so as not to contaminate.

  When the external electrode 19 is used as an anode, the plasma 29 is generated linearly as shown in FIG. 1, and a high density plasma is locally generated in the vapor deposition space. The particles immediately after evaporation pass through the high-density plasma generated between the holocathode gun 17 and the external electrode 18, so that activation is violently promoted, and the evaporated particles 28 not only obtain kinetic energy but also ionize. The ionization of the plasma sheath including the Ar ions is performed and incident on the film base 27 with acceleration of the plasma sheath. Therefore, it is preferable that the external electrode 19 is installed at a position where the region where the plasma 29 is generated overlaps the region where the evaporated particles 28 exist.

  Whether the plasma 29 generated from the holocathode gun 17 is spread over the entire film forming chamber 10 by the internal electrode 18 or locally increased in the film forming chamber 10 by the external electrode 19 is determined by the switch 24 and the switch 26. It becomes possible by switching. Whether the plasma 29 is spread over the entire film forming chamber 10 or locally increased in the film forming chamber 10 depends on the type and shape of the vapor deposition material 16 and the width direction of the film formed on the film 27. It depends on the required level of sex, and can be selected accordingly.

  In the embodiment of the present invention, two anodes of the internal electrode 18 and the external electrode 19 are provided for one holocathode. However, depending on the application, the internal electrode 18 or the external electrode 19 is provided for one holocathode. One anode may be installed.

  Further, a plurality of holocathode guns 17 may be installed in the film forming apparatus depending on the size of the film substrate 27 in the width direction. When the external electrode 19 is used as an anode, a plurality of holocathode guns 17 are provided depending on the number of holocathode guns 17. May be installed.

  The discharge condition of the plasma 29 is preferably as the plasma density is higher as the current value is higher at several A to several hundred A per holocathode. However, when the flow rate of the gas introduced into the holocathode gun 17 is large or the flow rate of the gas introduced from the gas pipe 23 is large, the pressure in the deposition chamber 10 depends on the exhaust capacity of the pump that exhausts the deposition chamber 10. And the mean free path of the evaporated particles 28 may become too short. In such a case, the evaporated particles 28 to be activated lose kinetic energy, and the film density and adhesion of the film to be formed are reduced. For this reason, the discharge conditions of the holocathode need to be determined in view of the type of gas introduced into the holocathode, the type of gas introduced from the gas pipe 23, and the type of vapor deposition material 16.

  Further, the film forming apparatus of the present invention includes means for accelerating the vaporized particles 28 by an electric field and entering the film base material 27. An electric field acceleration power source 22 is connected to the main roller 14, and the evaporated particles 28 evaporated from the vapor deposition material 16 can be accelerated by the electric field and incident on the film substrate 27 with high kinetic energy.

  The electric field acceleration power source 22 may be any one of a direct current power source, a direct current pulse power source, and an alternating current power source. However, when a direct current pulse power source or an alternating current power source is used, it is necessary to appropriately determine the frequency in accordance with the film formation rate.

  The application condition of the electric field acceleration power source 22 is that the voltage is applied to the main roller 14, so that the applied voltage is such that no discharge occurs on the winding chamber 11 side. If it is a grade which is not carried out, there will be no restriction | limiting in particular.

  The film forming apparatus of the present invention uses a means for accelerating Ar ions in the vaporized particles 28 and plasma 29 by an electric field and entering the film substrate 27 together with a means for activating the vaporized particles 28 with the plasma 29. Since the evaporated particles 28 activated by the plasma 29 can be accelerated by an electric field and incident on the film with high kinetic energy, a denser film can be formed.

  Further, the film forming apparatus of the present invention can use electron beam heating by the electron beam gun 25 instead of the resistance heating type by the material filling type resistance heating crucible 15. In this case, the resistance heating crucible 15 for material filling is a ground electrode.

  In FIG. 1, the resistance heating crucible 15 for material filling and the electron beam gun 25 are installed, but the means for evaporating the vapor deposition material of the present invention may be an induction heating method. A plurality of means of electron beam heating, induction heating, and resistance heating may be used.

  In the case of electron beam heating, examples of the electron beam gun include a straight electron beam gun and a deflected electron beam gun. In the present invention, it is particularly preferable to use a straight electron beam gun.

  The definition of the straight electron beam gun here is a deflected electron beam gun that controls the direction of travel of the electron beam generated from the gun by preparing an orthogonal magnetic field in the deposition space, regardless of the method of electron generation or convergence. The advantage of using the straight electron beam gun is that an orthogonal magnetic field for bending the traveling direction of the electron beam is not used in the deposition space in order to apply the electron beam to the vapor deposition material 16, and for this reason. Interference with the plasma emitted from the holocathode gun does not occur. Since a deflected electron beam gun or the like actively uses an orthogonal magnetic field in the film forming space in order to apply electrons to the evaporation material 16, a magnetic field is generated in the space in the film forming chamber, and diffusion of electrons ejected from the holocathode gun. Therefore, it is necessary to arrange the mounting position of the deflected electron beam and the mounting position of the holo-cathode gun so that interference does not occur. In addition, complexity is required. In the case of using a straight electron beam gun, it is necessary to set a certain angle and position in advance so that the electron beam linearly strikes the vapor deposition material 16 as shown in FIG. Furthermore, examples of the electron beam gun itself include, but are not limited to, a Pierce type flat cathode electron gun and a circular cross-section converging electron gun.

  When an induction heating method or a deflected electron beam gun is used, interference with the plasma itself generated from the holocathode gun 17 may occur, so it is necessary to install the holocathode gun 17 in an arrangement that does not cause interference. There is. For this reason, the resistance heating method or the electron beam heating method using a straight electron beam gun is easier to handle as the evaporation method. In addition, when a magnetic field such as a converging magnetic field is provided on the holocathode gun 17 and the external electrode 19, interference may occur regardless of whether the electron beam method is deflected or straight forward. The resistance heating method becomes easier to handle.

The gas barrier laminate formed by the film forming apparatus of the present invention preferably has a water vapor permeability of 1 g / m ² / day or more. The film forming apparatus of the present invention can freely set the evaporation rate of the material and the plasma density, and can freely set the gas barrier property with respect to the film forming speed. A gas barrier laminate having excellent barrier properties can be produced.

Furthermore, the gas barrier laminate formed by the film forming apparatus of the present invention preferably has an oxygen permeability of 1 cc / m ² / day or more. The film forming apparatus of the present invention can freely set the evaporation rate of the material and the plasma density, and can freely set the gas barrier property with respect to the film forming rate. Thus, a gas barrier laminate excellent in oxygen barrier property can be produced.

  Specific examples of the present invention are shown below.

<Example 1>
Using the film forming apparatus shown in FIG. 1, the material-filled resistance heating crucible 15 is filled with aluminum, evaporated at a film forming rate of 100 nm / sec by a resistance heating method, oxygen gas is introduced from the gas pipe 23, and the reactivity is increased. An aluminum oxide thin film was deposited by vapor deposition, and a PET film having a thickness of 12 μm was flowed from the unwinding roller 12 toward the winding roller 13 to form a physical film thickness of 20 nm. At this time, argon was passed through the holocathode gun 17 at 200 sccm, and a 50 V, 60 A discharge was generated between the holocathode discharge DC power supply 21 and the counter electrode 18.

<Example 2>
Using the film forming apparatus shown in FIG. 1, the material-filled resistance heating crucible 15 is filled with aluminum, evaporated at a film forming rate of 100 nm / sec by a resistance heating method, oxygen gas is introduced from the gas pipe 23, and the reactivity is increased. An aluminum oxide thin film was deposited by vapor deposition, and a PET film having a thickness of 12 μm was flowed from the unwinding roller 12 toward the winding roller 13 to form a physical film thickness of 20 nm. At this time, argon was supplied to the holocathode gun 17 at 200 sccm, and a discharge of 70 V and 120 A was generated between the counter electrode 18 and the DC power supply 21 for the holocathode discharge.

<Example 3>
Using the film forming apparatus shown in FIG. 1, the material-filled resistance heating crucible 15 is filled with aluminum, evaporated at a film forming rate of 100 nm / sec by a resistance heating method, oxygen gas is introduced from the gas pipe 23, and the reactivity is increased. An aluminum oxide thin film was deposited by vapor deposition, and a PET film having a thickness of 12 μm was flowed from the unwinding roller 12 toward the winding roller 13 to form a physical film thickness of 20 nm. At this time, argon is supplied to the holocathode gun 17 at 200 sccm, a 50 V, 60 A discharge is generated between the holocathode discharge DC power supply 21 and the counter electrode 18, and a 50 kHz AC power supply is used as the electric field acceleration power supply. , 600 W was applied.

<Example 4>
Using the film forming apparatus shown in FIG. 1, the material-filled resistance heating crucible 15 is filled with aluminum, evaporated at a film forming rate of 100 nm / sec by a resistance heating method, oxygen gas is introduced from the gas pipe 23, and the reactivity is increased. An aluminum oxide thin film was deposited by vapor deposition, and a PET film having a thickness of 12 μm was flowed from the unwinding roller 12 toward the winding roller 13 to form a physical film thickness of 20 nm. At this time, argon is supplied to the holocathode gun 17 at 200 sccm, a discharge of 70 V and 120 A is generated between the holocathode discharge DC power supply 21 and the counter electrode 18, and a 50 kHz AC power supply is used as the electric field acceleration power supply. , 600 W was applied.

<Comparative Example 1>
Using the film forming apparatus shown in FIG. 1, the material-filled resistance heating crucible 15 is filled with aluminum, evaporated at a film forming rate of 100 nm / sec by a resistance heating method, oxygen gas is introduced from the gas pipe 23, and the reactivity is increased. An aluminum oxide thin film was deposited by vapor deposition, and a PET film having a thickness of 12 μm was flowed from the unwinding roller 12 toward the winding roller 13 to form a physical film thickness of 20 nm.

  About the created sample, water vapor permeability and oxygen permeability were measured by the following methods.

(Evaluation method)
The water vapor permeability was measured by the MOCON method. The measuring instrument used was measured by MOCON PERMATRAN 3/33 at 40 ° C. and 90% Rh, and the oxygen permeability was measured by MOCON OX-TRAN 2/20 at 23 ° C. and 0% Rh.

  Table 1 shows the water vapor permeability and oxygen permeability of the samples prepared in Example 1, Example 2, Example 3, Example 4, and Comparative Example 1.

  From the results of Table 1, when the film forming apparatus of the present invention is used, a result showing high water vapor barrier properties and oxygen barrier properties is obtained at high speed film formation of 100 nm / sec, and the gas barrier is improved by electric field acceleration. was gotten.

  The film forming apparatus of the present invention is an apparatus for producing an oxygen and water vapor barrier laminate, and the produced oxygen and water vapor barrier laminate is an optical film, an optical functional filter or the like in addition to the barrier member. It is also used for members.

DESCRIPTION OF SYMBOLS 10 ... Film-forming chamber 11 ... Winding chamber 12 ... Unwinding roller 13 ... Winding roller 14 ... Main roller 15 ... Material filling type resistance heating crucible 16 ... Deposition Material 17 ... Holocathode gun 18 ... Internal electrode 19 ... External electrode 20 ... Resistance heating DC power supply 21 ... Holocathode discharge DC power supply 22 ... Electric field acceleration power supply 23 ... Gas pipe 24 ... Switch 25 ... Electron beam gun 26 ... Switch 27 ... Film substrate 28 ... Evaporated particles 29 ... Plasma 30 ... Film forming device 31 ... Holo cathode 32. ··anode

Claims (5)

A film forming apparatus comprising: a transport unit that transports a film substrate in a roll-to-roll manner; and a deposition unit that deposits a deposition material on the film substrate,
The vapor deposition means has means for evaporating the vapor deposition material, and means for activating the vaporized vapor deposition material with plasma,
The means for evaporating the vapor deposition material is electron beam heating, and the electron beam used for the electron beam heating is a straight electron beam,
A film forming apparatus characterized in that the means for activating the evaporated deposition material with plasma is a holocathode discharge.   2. The film forming apparatus according to claim 1, wherein the vapor deposition means includes means for accelerating the evaporated vapor deposition material by an electric field and depositing the vapor deposition material on the film substrate.   The film forming apparatus according to claim 1, wherein the anode is installed around the holocathode in the holocathode and the anode used for the holocathode discharge.   The film forming apparatus according to claim 1, wherein in the holocathode and the anode used for the holocathode discharge, the anode is installed at a position facing the holocathode with the vapor deposition material interposed therebetween.   The composition according to claim 1, wherein the holocathode and the anode used for the holocathode discharge are respectively disposed around the holocathode and at a position facing the holocathode with the vapor deposition material interposed therebetween. Membrane device.

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