JP2013204053A - Film-forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a film-forming apparatus capable of forming a thin film with high film uniformity on a surface of a film formation target having flexibility.SOLUTION: In a film-forming apparatus, a placement surface 14 of a target placement part 13 on which a film formation target 12 is placed is a curved surface, and raw material gas release parts 20and 202 each has: a release container 21; a release plate 22 arranged on a surface of the release container 21 facing the placement surface 14, wherein the release plate 22 is curved in parallel to the placement surface 14; a diffusing plate 23 that is placed to parallelly face the release plate 22 inside the release container 21, thereby separating the interior space of the release container 21 into a first space 24 wherein the release plate 22 is exposed and a second space 25 which is the other space; and a raw material gas source 26 connected to the second space 25. At intersections of a regular n-sided polygonal lattice (wherein n is an integer of 3-6) of the release plate 22, release pores 28 are formed along a normal direction of the placement surface 14, and at intersections of the diffusing plate 23 and normal lines of the placement surface 14 passing through centers of the regular n-sided polygonal lattice of the release plate 22, diffusing pores 29 are formed along the normal direction of the placement surface 14.

Description

  The present invention relates to a film forming apparatus, and more particularly to a film forming apparatus used for manufacturing an organic semiconductor element such as an organic EL display and an organic EL lighting device.

  Since organic EL elements have high luminous efficiency and can assemble thin light emitting devices, they are attracting attention for use in display devices and lighting equipment. At present, organic EL elements are formed on thin and flexible film substrates. Technology has been proposed.

Since the organic EL element has a property of deteriorating and shortening its life when moisture enters the organic layer, a sealing technique for shielding from moisture in the atmosphere is required.
As a sealing technique using a thin film, a method of forming an inorganic thin film such as SiN by a plasma chemical vapor deposition (plasma CVD) method having a low film forming temperature is known.

  Referring to FIG. 8, in a conventional film forming apparatus 100 that forms a sealing film on a film formation target 112 that is a film substrate by a plasma CVD method, a source gas introduced into a discharge container 121 from a source gas source 126. Are emitted from a plurality of emission holes 128 provided in the emission plate 122 into the film formation space 116 and converted into plasma, and a sealing film made of a chemical reaction product of the source gas is formed on the surface of the film formation target 112. Is done.

  However, in the conventional film forming apparatus 100, the source gas distribution in the film forming space 116 is uneven, and the film uniformity of the formed sealing film is deteriorated. As a result, the transmitted light transmitted through the sealing film is reduced. There is a problem that lightness and darkness occur in the strength, and pinholes are formed in the sealing film, resulting in insufficient sealing performance.

  The following Patent Documents 1 and 2 disclose a configuration in which the discharge plate 122 is bent in parallel with the outer peripheral side surface of the object placement unit 113.

JP 2006-152416 A International Publication No. 2008/026242

  In the configurations disclosed in Patent Documents 1 and 2, although the gaps between the discharge holes 128 and the surface of the film formation target 112 are evenly arranged, each of the source gases introduced into the discharge container 121 is arranged. There is a difference between the discharge holes 128 in the amount reaching the discharge holes 128.

  When the area of the discharge plate 122 increases as the film formation target 112 becomes larger, the difference in the amount of source gas reaching each discharge hole 128 widens, and the flow rate of the source gas discharged from each discharge hole 128 is released. There was a problem of non-uniformity between the holes 128.

  The present invention was created to solve the above-described disadvantages of the prior art, and its purpose is to provide a film forming apparatus capable of forming a thin film with good film uniformity on the surface of a flexible film forming object. There is to do.

In order to solve the above-described problems, the present invention provides a vacuum chamber, a source gas discharge unit that discharges a source gas in the vacuum chamber, and a film formation target, and the source gas is formed on the surface of the film formation target. An object placement portion on which the thin film is formed, wherein the placement surface on which the film formation subject of the subject placement portion is placed is a curved surface, and the source gas discharge portion is A discharge vessel into which the source gas is introduced; a discharge plate provided on a surface opposite to the arrangement surface of the discharge vessel; bent in parallel to the arrangement surface; and parallel to the discharge plate inside the discharge vessel A diffusion plate that is arranged opposite to the first container and that separates the internal space of the discharge container into a first space where the back surface of the discharge plate is exposed and the other second space, and is connected to the second space A regular n-gonal lattice (n is not less than 3 and not more than 6). (E.g., an integer) is provided with discharge holes along the normal direction of the arrangement surface, and at the intersection of the normal of the arrangement surface passing through the center of the regular n-gonal lattice and the diffusion plate. The film forming apparatus is provided with diffusion holes along the normal direction of the arrangement surface.
This invention is a film-forming apparatus, Comprising: The said object arrangement | positioning part is a cylindrical shape, The said arrangement | positioning surface is a film-forming apparatus provided in the outer peripheral side surface of the said object arrangement | positioning part.
The present invention is a film forming apparatus, wherein a total area of the openings of the discharge holes is the same as a total area of the openings of the diffusion holes.
The present invention is a film forming apparatus comprising a voltage supply unit that applies a voltage to the emission plate and generates plasma of the source gas in the film forming space, and the thin film is formed by a plasma CVD method. It is a membrane device.
The present invention is a film forming apparatus, comprising: a ring magnet arranged in parallel with the arrangement surface in the second space; and a center magnet arranged inside a ring of the ring magnet, wherein the ring The surface of the magnet directed to the placement surface and the surface of the central magnet directed to the placement surface are magnetic film deposition apparatuses that are provided with magnetic poles of opposite polarities and located at an equal distance from the placement surface. .
The present invention is a film forming apparatus, wherein the discharge container is provided with a heating unit that heats the discharge container to a temperature equal to or higher than a condensation temperature of the source gas, and the thin film is formed by a vacuum evaporation method. is there.

  Discharge holes are provided at equal intervals in the discharge plate bent parallel to the arrangement surface, and the source gas introduced into the second space of the discharge container is uniformly diffused in the first space and then discharged Since the material gas is discharged from the holes into the film formation space, the uniformity of the raw material gas distribution in the film formation space is improved, and a thin film with good film uniformity is formed even on the surface of the film formation target having a curved surface.

Internal configuration diagram of an example of a film forming apparatus of the present invention The figure for demonstrating embodiment provided with an unwinding axis | shaft and a winding axis | shaft. Partial enlarged plan view of the discharge plate and diffuser plate in the state returned to the flat plate The figure for demonstrating embodiment provided with a ring magnet and a center magnet The figure for demonstrating embodiment provided with a some diffuser plate FIG. (1) for explaining another example of the structure of the source gas discharge part FIG. (2) for explaining another example of the structure of the source gas discharge part Internal configuration diagram of conventional film deposition system

With reference to FIG. 1, an example of the structure of the film forming apparatus 10 of the present invention will be described.
A film forming apparatus 10 according to the present invention includes a vacuum chamber 11, source gas discharge units 20 ₁ and 20 ₂ that discharge a source gas into the vacuum chamber 11, and a film formation target 12. And an object disposition portion 13 on the surface of which a thin film of source gas is formed.
A vacuum exhaust unit 19 is connected to the vacuum chamber 11. When the evacuation unit 19 is operated, the vacuum chamber 11 is evacuated to form a vacuum atmosphere.

The arrangement surface 14 on which the film formation object 12 of the object arrangement unit 13 is arranged is a curved surface.
In the present embodiment, the object placement unit 13 has a cylindrical shape, and the placement surface 14 is provided on the outer peripheral side surface of the object placement unit 13. The shape of the object placement unit 13 is not limited to a cylindrical shape as long as it has a curved placement surface 14, and may be, for example, a spherical shape.

  With reference to FIG. 2, in this embodiment, the vacuum chamber 11 includes a first sub-vacuum chamber 51 having an unwinding shaft 53 disposed therein, and a second sub-vacuum having a winding shaft 54 disposed therein. The vacuum chambers 52 are hermetically connected to each other. Vacuum exhaust parts 55 and 56 are connected to the first and second sub vacuum chambers 51 and 52, respectively, and the inside is evacuated.

  The central axis of the unwinding shaft 53 and the central axis of the winding shaft 54 are directed parallel to the central axis of the object disposing unit 13, respectively, and the object disposing unit 13, the unwinding shaft 53, and the winding shaft 54 are directed. Is configured to be rotatable about its own central axis.

The film formation target 12 is made of a flexible member, and the back surface of the film formation target 12 can be brought into close contact with the arrangement surface 14.
In this embodiment, the film formation target 12 is a belt-like film, and is attached to the unwinding shaft 53 in a state of being wound in a roll shape around one end, and is formed from the outer periphery of the roll. The end of the film is wound around the outer peripheral side surface of the object placement unit 13, and the rear surface of the film formation target 12 is brought into close contact with the outer peripheral side surface of the object placement unit 13. The part is wound around and attached to the take-up shaft 54. Reference numerals 18 ₁ to 18 ₄ denote auxiliary rollers for changing the direction of the film formation target 12.

  Here, a rotating device (not shown) is connected to the winding shaft 54, and when the winding shaft 54 rotates by receiving power from the rotating device, a force pulling from the winding shaft 54 to the film formation target 12 is applied, The object placement unit 13 and the unwinding shaft 53 rotate according to the pulling force, respectively, so that the film formation target 12 is fed out from the roll, and the fed film formation target 12 is the arrangement surface of the object placement unit 13. 14 passes along the outer peripheral direction, and is wound on the winding shaft 54.

In the present embodiment, the number of source gas discharge portions 20 ₁ , 20 ₂ is two, and they are arranged side by side along the outer peripheral direction of the object placement portion 13. In the present invention, the number of source gas discharge portions 20 ₁ and 20 ₂ is not limited to two, and may be one or three or more.

Structure of the raw material gas ejection section 20 _1, 20 ₂ are the same here, in the drawing of FIG. 1, reference numeral to the internal structure of the raw material gas ejection section of code 20 _1, the raw material gas discharge portion of the code 20 ₂ The reference numerals are omitted for the internal structure.

The source gas discharge portions 20 ₁ and 20 ₂ are provided on the release container 21 into which the source gas is introduced, and the release plate 22 provided on the surface facing the arrangement surface 14 of the release container 21 and bent parallel to the arrangement surface 14. The inside of the discharge container 21 is disposed in parallel with the discharge plate 22, and the internal space of the discharge container 21 is divided into a first space 24 where the back surface of the discharge plate 22 is exposed, and the other second space 25. And a source gas source 26 connected to the second space 25.

The discharge container 21 is elongated, and is disposed at a position facing the arrangement surface 14 in a state where the longitudinal direction is parallel to the central axis of the object arrangement unit 13, and the discharge plate 22 is disposed on the arrangement surface 14 of the discharge container 21. It is provided on one wall surface facing.
The discharge plate 22 and the diffusing plate 23 are bent with the same curvature as the arrangement surface 14, respectively, and are parallel to the arrangement surface 14.

FIG. 3 is a partially enlarged plan view of the emission plate 22 and the diffusion plate 23 in a state returned to the flat plate.
Emission holes 28 along the normal direction of the arrangement surface 14 are provided at the intersections of the regular n-gonal lattice (n is an integer of 3 or more and 6 or less) of the emission plate 22, respectively. Diffusion holes 29 along the normal direction of the arrangement surface 14 are provided at the intersections between the normal line of the arrangement surface 14 passing through the center of the regular n-gon and the center of the n-gon lattice and the diffusion plate 23. It has been.

In the present embodiment, each discharge hole 28 is provided at an intersection of a regular square lattice on the surface of the discharge plate 22, that is, is disposed on the surface of the discharge plate 22 at regular intervals.
In addition, each diffusion hole 29 includes a normal line of the arrangement surface 14 passing through the center of the regular tetragonal lattice on the emission plate 22 (ie, the center of gravity of a unit regular tetragon as a repeating unit of the regular tetragonal lattice), and the diffusion plate 23. Are arranged at equal intervals on the surface of the discharge plate 22, and their central axes are directed to the center of gravity of different unit squares on the discharge plate 22.

  Therefore, the distance between the four discharge holes 28 located at the apex of one unit regular quadrangle and the one diffusion hole 29 whose central axis is directed to the center of gravity of the unit regular quadrangle is the same, The source gas discharged from the one diffusion hole 29 to the first space 24 is uniformly diffused toward each discharge hole 28 at the apex of one unit tetragon surrounding the diffusion hole 29, and each discharge hole 28. The raw material gas having substantially the same flow rate reaches.

  Therefore, compared with the configuration in which the diffusion plate 23 is omitted, the difference in the flow rate of the source gas discharged from each discharge hole 28 to the film formation space 16 is reduced, and the source gas distribution in the film formation space 16 is reduced. The uniformity is improved.

  The total area of the openings of the discharge holes 28 is preferably the same as the total area of the openings of the diffusion holes 29. This is because as the total area of the openings of the discharge holes 28 is larger or smaller than the total area of the openings of the diffusion holes 29, the gas pressure gradient (that is, the gas flow) tends to become irregular.

In the present embodiment, the source gas discharge units 20 ₁ and 20 ₂ apply a voltage to the discharge plate 22 and generate a voltage supply for generating a plasma of the source gas in the film formation space 16 between the discharge plate 22 and the arrangement surface 14. A portion 27 is provided.
Here, the voltage supply unit 27 is electrically connected to the discharge plate 22 via the discharge container 21. The object placement unit 13 and the vacuum chamber 11 are placed at the ground potential.

  In the case where a thin film is formed on the surface of the film formation target 12 using the film forming apparatus 10 of the above-described form, first, the vacuum exhaust units 19, 55, 56 are operated, and the vacuum chambers 11, 51, 52 are operated. A vacuum atmosphere is formed respectively. Thereafter, evacuation is continued to maintain the vacuum atmosphere.

A source gas is introduced from the source gas source 26 into the second space 25 of the discharge container 21. For example, the source gas is a mixed gas of SiH ₄ gas, NH ₃ gas, and N ₂ gas.
The introduced source gas diffuses into the second space 25 and then is released into the first space 24 through each diffusion hole 29 of the diffusion plate 23.

  In the first space 24, the source gas discharged from one diffusion hole 29 is uniformly diffused toward the plurality of discharge holes 28 surrounding the diffusion hole 29, and the film formation space 16 is formed from each discharge hole 28. To be released. Therefore, the flow rate of the source gas discharged from each discharge hole 28 is uniform between the discharge holes 28.

  When an AC voltage is applied from the voltage supply unit 27 to the emission plate 22, the source gas released into the film formation space 16 is ionized to generate plasma, and the film formation target is in close contact with the arrangement surface 14 by plasma CVD. A thin film (for example, a SiN thin film) made of a reaction product of the source gas is formed on the surface of the object 12.

  The arrangement surface 14 and the discharge plate 22 are parallel to each other, and the discharge holes 28 are arranged at equal intervals on the surface of the discharge plate 22, so that the source gas discharged from each discharge hole 28 at a uniform flow rate is Thus, it is possible to suppress the occurrence of unevenness in the film thickness and film quality of the thin film formed by reaching the surface of the film formation target 12 at a uniform flow rate per unit area.

  When the winding shaft 54 is rotated and the film formation target 12 is moved along the outer peripheral direction of the target object placement unit 13, a thin film is continuously formed along the longitudinal direction of the film formation target 12.

While moving the film-forming target 12, when the raw material gas ejection section 20 _1, 20 ₂ are operated respectively, each passing through a position facing the emitting plate 22 of each raw material gas ejection section 20 _1, 20 _2, A thin film is laminated on the surface of the film formation target 12.

Referring to FIG. 4, the source gas discharge portions 20 ₁ and 20 ₂ are arranged in the second space 25 in parallel with the arrangement surface 14 and arranged inside the ring of the ring magnet 31. A central magnet 32 may be included.

  The surface of the ring magnet 31 facing the arrangement surface 14 and the surface of the center magnet 32 facing the arrangement surface 14 have magnetic poles having opposite polarities, and the other surfaces of the magnets 31 and 32 are arranged on the other surface. Here, the yoke 33 is in close contact. Therefore, a magnetic field is formed in the film formation space 16, and electrons in the plasma are confined in this magnetic field, and the plasma density in the film formation space 16 increases.

  The surface of the ring magnet 31 facing the arrangement surface 14 and the surface of the central magnet 32 facing the arrangement surface 14 are preferably located at an equal distance from the arrangement surface 14. In this case, the component parallel to the magnetic field arrangement surface 14 (horizontal component) is increased, the effect of confining charged particles is improved, and the plasma density in the discharge space is further increased.

Referring to FIG. 5, a plurality of diffusion plates 23 ₁ , 23 ₂ may be disposed inside the discharge container 21 so as to be spaced apart from each other.
Preferably, each diffusion plate 23 ₁ , 23 ₂ is bent parallel to each other, and the diffusion holes 29 ₁ , 29 ₂ of each diffusion plate 23 ₁ , 23 ₂ are provided at the intersections of regular n-gonal lattices, and their central axes Is directed to the center of the regular n-gonal lattice of adjacent diffusion plates 23 ₂ , 23 ₁ .

In this configuration, the source gas introduced into the second space 25 diffuses between the adjacent diffusion plates 23 ₁ and 23 ₂ and then diffuses in the first space 24. Therefore, the difference between the discharge holes 28 in the flow rate of the raw material gas reaching each discharge hole 28 is further reduced.

(Another example of the structure of the source gas discharge part)
Note that the source gas discharge units 20 ₁ and 20 ₂ are not limited to the configuration including the voltage supply unit 27 described above.

Referring to FIG 6, another example of the structure of the raw material gas ejection section 20 _1, 20 _2, it will be described as a representative in the raw material gas discharge portion of the reference numeral 20 _1.
The raw material gas discharge unit 20 ₁ is provided in discharge vessel 21 has a heating unit 68 for heating the desorption chamber 21 above the condensation temperature of the feed gas.

  Here, the heating unit 68 is a resistance heater, and is provided in contact with the discharge plate 22 and the diffusion plate 23, respectively, and due to heat conduction from the heating unit 68, the discharge plate 22 and the diffusion plate 23 each condense the source gas. It is designed to be heated above the temperature.

  A heat radiation prevention means 66 for blocking heat radiation is disposed outside the discharge container 21, and the film formation target 12 and the target object placement unit 13 are heated by the heat radiation from the discharge container 21. Is preventing.

Source gas source 26, wherein the vapor deposition material 62 ₁ of liquid or solid, 62 ₂ and the vapor deposition case 61 _1, 61 ₂ for accommodating a vapor deposition case 61 _1, 61 deposition material 62 ₁ in the _2, 62 ₂ and the heating And material heating means 67 ₁ and 67 ₂ for evaporating.

Here vapor deposition case 61 _1, 61 number of ₂ is two, the one of the vapor deposition case 61 ₁ is arranged organic material 62 ₁ in the host and the other to the vapor deposition case 61 in _second organic materials of the dopant 62 ₂ is arranged.

The vapor deposition containers 61 ₁ and 61 ₂ are connected to the second space 25 of the discharge container 21 through openable and closable valves 63 ₁ and 63 ₂ . Further, a carrier gas source 65 is connected to the vapor deposition containers 61 ₁ and 61 ₂ via carrier gas flow rate control means 64 ₁ and 64 ₂ .

Here, the material heating means 67 ₁ and 67 ₂ are linear resistance heaters, and are wound around and attached to the outer peripheral surfaces of the vapor deposition containers 61 ₁ and 61 ₂ . Material heating unit 67 _1, 67 ₂ generates heat, the vapor deposition material 62 ₁ in the vapor deposition case 61 _1, 61 in ₂ by heat conduction, 62 ₂ is heated and evaporated, the vapor in the vapor deposition case 61 _1, 61 in ₂ To charge.

When the carrier gas is allowed to flow from the carrier gas source 65 into the vapor deposition containers 61 ₁ and 61 _{2 with the} valves 63 ₁ and 63 ₂ in the open state, the vapor deposition materials 62 ₁ and 62 ₁ in the vapor deposition containers 61 ₁ and 61 ₂ , respectively. The vapor 62 ₂ is introduced into the second space 25 of the discharge container 21 together with the carrier gas, diffused in the first space 24, discharged to the film formation space 16, and disposed on the arrangement surface 14 by vacuum deposition. An organic thin film made of a mixture of a host material and a dopant material is formed on the surface of the upper film formation target 12.

  The diffusion plate 23 and the discharge plate 22 are each heated by the heating unit 68 to a temperature equal to or higher than the condensation temperature of the raw material gas, and the condensation of the raw material gas in the discharge container 21 to the diffusion plate 23 or the discharge plate 22 is suppressed. It is prevented that the diffusion hole 29 or the discharge hole 28 is blocked by an object.

Therefore, even if the film formation is continued for a long time while moving the film formation target 12 in the outer peripheral direction of the target placement unit 13, the source gas is not condensed in the discharge container 21, and the diffusion holes 29 and the discharge holes 28 are not formed. The film uniformity of the formed thin film is maintained without being blocked.
The number of vapor deposition containers 61 ₁ and 61 ₂ is not limited to two, and may be one or three or more.

  In the drawing of FIG. 6, the tip of the discharge hole 28 protrudes from the discharge plate 22, that is, is formed in a nozzle shape, but the present invention is not limited to this, and the tip of the discharge hole 28 as shown in FIG. 1. May be flat.

Further, referring to FIG. 7, the carrier gas source 65 and the carrier gas flow rate control means 64 ₁ and 64 ₂ may be omitted from the source gas source 26.
In the case of forming a thin film with this configuration, for example, a monomer material is used for the vapor deposition materials 62 ₁ and 62 ₂ , the vapor of the monomer material is introduced into the second space 25 of the discharge container 21, and the first space 24 is formed. After being diffused, the vapor of the monomer material is vapor-deposited on the surface of the film formation target 12 to form a polymer thin film.

10 ...... deposition apparatus 11 ...... vacuum tank 12 ...... forming target 13 ...... object placement unit 20 _1, 20 ₂ ...... material gas discharge unit 21 ...... desorption chamber 22 ...... emitting plate 23 ...... diffusion Plate 24 …… First space 25 …… Second space 26 …… Source gas source 27 …… Voltage supply unit 28 …… Discharge hole 29 …… Diffusion hole

Claims (6)

A vacuum chamber;
A source gas discharge part for releasing source gas into the vacuum chamber;
An object placement unit in which a film formation target is disposed, and a thin film of the source gas is formed on a surface of the film formation target;
A film forming apparatus comprising:
The arrangement surface on which the film formation object of the object arrangement unit is arranged is a curved surface,
The source gas discharge part is
A discharge container into which the source gas is introduced;
A discharge plate provided on a surface facing the arrangement surface of the discharge container and bent parallel to the arrangement surface;
Arranged parallel to the discharge plate inside the discharge container, the internal space of the discharge container is separated into a first space in which the back surface of the discharge plate is exposed and the other second space. A diffusion plate,
A source gas source connected to the second space;
Have
At the intersections of regular n-gonal lattices (n is an integer of 3 or more and 6 or less) of the discharge plate, discharge holes are provided along the normal direction of the arrangement surface, respectively.
A film forming apparatus in which a diffusion hole along a normal direction of the arrangement surface is provided at an intersection between the normal line of the arrangement surface passing through the center of the regular n-gonal lattice and the diffusion plate.   The film forming apparatus according to claim 1, wherein the object disposition unit has a cylindrical shape, and the disposition surface is provided on an outer peripheral side surface of the object disposition unit.   The film forming apparatus according to claim 1, wherein a total area of the openings of the discharge holes is the same as a total area of the openings of the diffusion holes. A voltage supply unit that applies a voltage to the emission plate and generates plasma of the source gas in the film formation space;
The film forming apparatus according to claim 1, wherein the thin film is formed by a plasma CVD method. A ring magnet arranged in the second space in parallel with the arrangement surface;
A central magnet disposed inside the ring of the ring magnet;
Have
5. The surface of the ring magnet directed to the arrangement surface and the surface of the central magnet directed to the arrangement surface are provided with magnetic poles having opposite polarities, and are located at an equal distance from the arrangement surface. The film-forming apparatus of description. The discharge container is provided with a heating unit that heats the discharge container to a temperature equal to or higher than the condensation temperature of the source gas,
The film forming apparatus according to claim 1, wherein the thin film is formed by a vacuum deposition method.

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