JP2017110284A - Evaporation source, and rolling type vacuum evaporation system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rolling type vacuum evaporation system capable of retaining a stable film quality while blocking a heat radiation from an evaporation source, and a take-up type vacuum evaporation system equipped with the evaporation source.SOLUTION: An evaporation source 6 according to one embodiment of the present invention comprises a crucible 61, an induction coil 62 and a shield member 63. The crucible 61 includes an accommodation part 611 capable of accommodating an evaporation material EM, and an opening end part 613 formed with an opening part 612 for ejecting the steam of the evaporation material EM accommodated in the accommodation part 611. The induction coil 62 is arranged around the crucible 61. The shield member 63 is so arranged on the outer peripheral side as to oppose the opening end part 613 on the opening part 612, and is made of a material having an adiabaticity.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an induction heating type evaporation source and a take-up vacuum deposition apparatus including the same.

  Conventionally, while winding a long base film continuously or intermittently fed from a winding roller around a cooling roller, an evaporation substance from an evaporation source arranged facing the cooling roller is placed on the base film. 2. Description of the Related Art A take-up vacuum vapor deposition apparatus that vapor-deposits and winds a base film after vapor deposition with a take-up roller is known (for example, see Patent Document 1).

  For the heating of the evaporating substance in the evaporation source constituting this type of take-up vacuum deposition apparatus, a method using induction heating, a method using resistance heating, a method using electron beam irradiation, or the like is used. The base film used in the wind-up type vacuum vapor deposition apparatus is generally intended for long films of 1000 m or longer, so either store sufficient evaporation material in the evaporation source or supply evaporation material to the evaporation source. Is required. In addition, an appropriate heating method is adopted depending on the evaporation required temperature of the evaporated substance.

  For example, an electron beam heating evaporation source can store an evaporation material in a hearth, and can supply an evaporation material, so that it can be used as an evaporation source for many substances. However, since a high-energy electron beam is used to heat the evaporation material, the base film is charged by reflected electrons from the evaporation material, which may hinder film running.

  Further, the resistance heating type evaporation source has a structure that heats the evaporation material by passing an electric current through the resistor, and therefore has an advantage that it can be configured at a relatively low cost. However, in order to make it possible to form a film on a long base film, a material supply mechanism capable of stably supplying the evaporation material to the evaporation source is required, and as a supply form, continuous supply is possible. It is necessary to process the evaporation material into a wire shape as much as possible. The evaporating material that can meet such requirements is limited to a specific material such as aluminum, and in order to continue supplying the aluminum wire that has not been degassed, a gas reservoir or resistor contained in aluminum and aluminum Splash occurs due to continuous contact of the film, and it is difficult to maintain high film formation quality.

  On the other hand, the induction heating type evaporation source can store a sufficient amount of evaporation material in the crucible, so that it can sufficiently support film formation on a long base film. There is an advantage that it is also suitable for evaporation of substances. For this reason, induction heating type evaporation sources are used in many fields as evaporation sources for base films such as plastic films, fabrics, glass films, metal foils and the like.

  On the other hand, in recent years, a base film on which an undercoat has been applied in advance, a base film on which a device has been formed, a base film with a very small heat capacity, a base film that is weak against heat load, or an extremely thin base film. The demand for is increasing. For this reason, in order to reduce the influence of the base film due to heat radiation from the induction heating type evaporation source, a technique for suppressing the heat input of the base film and reducing the damage due to the thermal load is indispensable.

  Therefore, for example, Patent Document 2 discloses an induction heating type evaporation source, which is a container that stores an evaporation material, an induction coil that is disposed around the container, and a thermal insulation that is disposed between the container and the induction coil. A structure is disclosed that includes a material and a ceramic disc body in which a vapor deposition hole having a diameter slightly larger than the diameter of the container is formed in the central portion, and blocks the heat released from the evaporation source to the substrate by the disc body. ing. Patent Document 3 discloses a method for producing a continuous vapor deposition film in which a cooling plate for shielding radiant heat from the evaporation source is disposed between the evaporation source and the film.

Japanese Patent No. 3795518 JP 2005-38646 A JP-A-11-323552

  However, in the evaporation source structure described in Patent Document 2, since the container is formed of a material that is not subjected to high-frequency induction heating, the heating efficiency of the evaporation material is poor, and thus the power consumption required for evaporation increases. is there. In addition, since the container faces the substrate through the vapor deposition hole of the disk, heat radiation from the container to the substrate cannot be blocked.

  On the other hand, although the cooling plate described in Patent Document 3 can block the heat radiation from the evaporation source to the film, the vapor flow released from the evaporation source to the film is hindered by the cooling plate. May change. For example, the evaporation material adheres to the opening of the cooling plate through which the vapor flow passes, so that the size of the opening changes with time (becomes narrower), thereby maintaining a stable film formation rate. Disappear. As a result, the film cannot be stably formed with a certain film quality.

  In view of the circumstances as described above, an object of the present invention is to provide an evaporation source capable of ensuring stable film formation quality while blocking heat radiation from the evaporation source, and a wind-up type vacuum evaporation apparatus equipped with the evaporation source. It is to provide.

In order to achieve the above object, an evaporation source according to an aspect of the present invention includes a crucible, an induction heating coil, and a first shield member.
The crucible has a housing portion that can store the evaporating material, and an opening end portion in which an opening that discharges the vapor of the evaporating material stored in the housing portion is formed.
The coil is disposed around the crucible.
The first shield member is disposed on the outer peripheral side of the opening so as to face the opening end, and is made of a material having heat insulation properties.

  Since the evaporation source includes the first shield member having heat insulation disposed on the outer peripheral side of the opening of the crucible so as to face the opening end of the crucible, the vapor of the evaporation material discharged from the opening Radiation heat from the crucible can be shut off without hindering the flow.

  The opening typically has a circular shape. In this case, the first shield member is formed of an annular plate member having an inner diameter larger than the opening diameter of the opening.

The first shield member may be made of a material having a higher specific resistance than the crucible.
Thereby, the temperature rise by the induction heating of the 1st shield member can be suppressed, and the heat shielding function by the 1st shield member can be secured.

  Alternatively, the eddy current flowing circuit formed by the induced magnetic flux from the coil in the first shield member has a higher resistance value than the eddy current flowing circuit formed by the induced magnetic flux from the coil in the crucible. May be.

The evaporation source may further include a second shield member. The said 2nd shield member is arrange | positioned on the outer peripheral side of the said opening part through the said 1st shield member, facing the said opening edge part, and is comprised with the material which has heat insulation.
Thereby, the interruption | blocking function of the heat radiation from a crucible can further be improved.

The second shield member may be made of a material having a higher specific resistance than the first shield member.
Thereby, the temperature rise by the induction heating of the 2nd shield member can be suppressed, and the heat shielding function by the 2nd shield member can be secured.

A take-up vacuum deposition apparatus according to an embodiment of the present invention includes a vacuum chamber, a film transport mechanism, and an evaporation source.
The film transport mechanism includes an unwinding roller that unwinds the film and a winding roller that winds the film unrolled from the unwinding roller, and is disposed inside the vacuum chamber.
The evaporation source forms a deposited film on the film transported by the film transport mechanism.
The evaporation source includes a crucible, an induction heating coil, and a first shield member. The crucible has a housing portion that can store the evaporating material, and an opening end portion in which an opening that discharges the vapor of the evaporating material stored in the housing portion is formed. The coil is disposed around the crucible. The first shield member is disposed on the outer peripheral side of the opening so as to face the opening end, and is made of a material having heat insulation properties.

  In the above winding type vacuum vapor deposition apparatus, the evaporation source includes the first shield member having heat insulation disposed on the outer peripheral side of the crucible opening and facing the opening end of the crucible. The radiation heat from the crucible can be blocked without hindering the vapor flow of the evaporating material released from the crucible. Thereby, the stable film-forming quality can be ensured, suppressing the damage by the thermal load of a film.

  As described above, according to the present invention, stable film formation quality can be ensured while blocking heat radiation from the evaporation source.

It is a schematic longitudinal cross-sectional view which shows the structure of the winding type vacuum evaporation system which concerns on the 1st Embodiment of this invention. It is an expanded sectional view which shows the detail of the evaporation source in the said winding-type vacuum deposition apparatus. It is a sectional side view which shows the relationship between the crucible and the shield member in the said evaporation source, A shows the state which the shield member isolate | separated from the crucible, B is the state by which the shield member was mounted in the opening edge part of a crucible Is shown. It is a top view of the shield member in the said evaporation source. It is a schematic sectional side view which shows the modification of the structure of the said shield member. It is a schematic plan view which shows the arrangement | sequence form of the evaporation source in the said winding-type vacuum deposition apparatus. It is a schematic longitudinal cross-sectional view which shows the structure of the evaporation source which concerns on the 2nd Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

<First Embodiment>
FIG. 1 is a schematic longitudinal sectional view showing a configuration of a winding type vacuum vapor deposition apparatus (hereinafter referred to as a vapor deposition apparatus) according to a first embodiment of the present invention.
In the figure, an X axis, a Y axis, and a Z axis indicate three axial directions orthogonal to each other. In the present embodiment, the X axis and the Y axis indicate a horizontal direction, and the Z axis indicates a height direction.

[Overall configuration of vapor deposition equipment]
The vapor deposition apparatus 1 includes an unwinding roller 2, a winding roller 3, a main roller 4, an evaporation source 6, and a vacuum chamber 7 that accommodates these.

(Vacuum chamber)
The vacuum chamber 7 has a sealed structure and is connected to the vacuum pump P through the exhaust line L. Thereby, the vacuum chamber 7 is configured such that the inside thereof can be evacuated or maintained in a predetermined reduced pressure atmosphere.

  The vacuum chamber 7 has a partition plate 8 inside. The partition plate 8 is disposed at a substantially central portion in the Z-axis direction of the vacuum chamber 7 and has an opening having a predetermined size. The peripheral edge of the opening is opposed to the outer peripheral surface of the main roller 4 with a predetermined gap. The interior of the vacuum chamber 7 is partitioned by a partition plate 8 into a transfer chamber 9 that is above the partition plate 8 in the Z-axis direction and a film formation chamber 10 that is below the partition plate 8 in the Z-axis direction.

An exhaust line L is connected to the film forming chamber 10. Therefore, when the inside of the vacuum chamber 7 is evacuated, first, the inside of the film forming chamber 10 is evacuated. On the other hand, since there is a predetermined gap between the partition plate 8 and the main roller 4 as described above, the inside of the transfer chamber 9 is also exhausted through this gap. Thereby, a pressure difference is generated between the film forming chamber 10 and the transfer chamber 9. By this pressure difference, it is possible to prevent the vapor flow of the evaporating material described later from entering the transfer chamber 9.
In this embodiment, the exhaust line L is connected only to the film forming chamber 10. However, by connecting another exhaust line to the transfer chamber 9, the transfer chamber 9 and the film forming chamber 10 can be connected simultaneously or independently. May be exhausted.

(Film transport mechanism)
The unwinding roller 2, the winding roller 3, the main roller 4, and the guide rollers 5 </ b> A to 5 </ b> H constitute a film transport mechanism 50. The unwinding roller 2, the winding roller 3, and the main roller 4 are each provided with a rotation drive unit (not shown) and configured to be rotatable around an axis parallel to the X axis.

  The unwinding roller 2 and the winding roller 3 are arranged in the transfer chamber 9 and are configured to be rotatable at a predetermined speed in a direction (clockwise) indicated by an arrow in FIG. The rotation direction of the unwinding roller 2 is not limited to this, and any direction may be used as long as the film can be fed toward the main roller 4. Similarly, the rotation direction of the winding roller 3 is not limited to the clockwise direction, and may be rotated in any direction as long as the film can be wound from the main roller 4.

  The main roller 4 is disposed between the unwinding roller 2 and the winding roller 3 in the film F conveyance path. Specifically, at least a part of the lower portion of the main roller 4 in the Z-axis direction is disposed at a position facing the film forming chamber 10 through an opening provided in the partition plate 8.

  Further, like the unwinding roller 2 and the winding roller 3, the main roller 4 is configured to be rotated clockwise at a predetermined speed by a rotation driving unit. Further, the main roller 4 is formed in a cylindrical shape from a metal material such as iron or stainless steel, and has a cooling medium or heat medium circulation mechanism (not shown) therein. Thereby, the film on the main roller 4 can be cooled or heated to a predetermined temperature. The size of the main roller 4 is not particularly limited, but typically, the length in the axial direction (axial length) is equal to or longer than the width of the film F.

  The guide rollers 5A, 5B, 5C, and 5D are disposed between the unwind roller 2 and the main roller 4 in the film F conveyance path, and guide the travel of the film F. The guide rollers 5E, 5F, 5G, and 5H are disposed between the take-up roller 3 and the main roller 4 in the film F conveyance path, and guide the travel of the film F. Each of the guide rollers 5A to 5H is typically configured by a free roller that does not include a unique rotation drive unit, but at least one of the guide rollers 5A to 5H is configured as a tension roller that can maintain or adjust the tension of the film F. May be.

  The film F is transported at a predetermined speed in the vacuum chamber 7 by the film transport mechanism 50 configured as described above. Although not shown, the film transport mechanism 50 further includes a charged beam irradiation device (for example, an ion beam irradiation device and an electron beam irradiation device) for surface cleaning and surface modification of the film F, and ions for removing the charge from the film F. A bombard mechanism, a degassing of the film F, a heater mechanism for removing moisture, and the like may be provided.

  The film F includes polyethylene terephthalate as a material, but is not limited thereto. Other materials include polyolefins such as polyethylene and polypropylene, polyesters such as polyethylene terephthalate and polyethylene naphthalate, polyamides such as nylon 6, nylon 66 and nylon 12, polyvinyl alcohol, polyimide, polyetherimide, polysulfone, polyethersulfone, Transparent resins such as polyetheretherketone, polycarbonate, polyarylate, or acrylic resin can be used. The film F may be a woven fabric, a glass film, a metal foil or the like.

  The thickness of the film F is not specifically limited, For example, it is about 1.2 micrometers-100 micrometers. Moreover, there is no restriction | limiting in particular about the width | variety and length of the film F, According to a use, it can select suitably. Typically, a long film of 1000 m or longer is used for the film F.

(Evaporation source)
The evaporation source 6 is disposed in the film forming chamber 10 and forms a vapor deposition film on the surface of the film F transported by the film transport mechanism 50. In the present embodiment, as shown in FIG. 1, the evaporation source 6 is disposed at a position immediately below the main roller 4 in the Z-axis direction, and is disposed on a support base 60 disposed at the bottom of the vacuum chamber 7.

  Although not shown, the film forming chamber 10 (see FIG. 1) has a protective layer for preventing vapor of the evaporation material EM released from the evaporation source 6 from being deposited on the inner wall surface of the vacuum chamber 7 or the partition plate 8. A mask member for partitioning a deposition plate and a film formation region for the film F on the main roller 4 may be disposed at an appropriate position.

  The evaporation source 6 includes a crucible 61 serving as a container for storing the evaporation material EM, an induction coil 62 for induction heating arranged around the crucible 61, and a shield member 63 (first shield member).

  The induction coil 62 is electrically connected to an AC power source (not shown) installed outside the vacuum chamber 7. The evaporation source 6 generates the vapor of the evaporation material EM to be deposited on the film formation surface of the film F on the main roller 4 by an induction heating method.

  The evaporation material EM is not particularly limited, and examples thereof include Ag, Al, Au, Cr, Cu, In, Sn, ZnS, and SiO. Further, the number of evaporation sources 6 is not limited to one, and a plurality of evaporation sources 6 may be used. In this case, a plurality of evaporation sources arranged linearly or in a staggered pattern along the width direction (X-axis direction) of the film F is used (see FIG. 6).

  FIG. 2 is an enlarged sectional view showing details of the evaporation source 6, and FIG. 3 is an enlarged sectional view of the crucible 61.

  The crucible 61 is made of a conductive material such as carbon, graphite, metal, or boron nitride (BN). The crucible 61 includes a storage portion 611 that can store the evaporating material EM, and an opening end 613 in which an opening 612 that discharges the vapor of the evaporating material EM stored in the storage portion 611 is formed (see FIG. 3). . The shape of the crucible 61 is not particularly limited. In the present embodiment, the crucible 61 is formed in a bottomed cylindrical shape, and the opening 612 has an opening diameter that is substantially the same as the outer diameter of the housing portion 611 when viewed from the Z-axis direction. A circular shape having an inner diameter).

  The induction coil 62 has a coil axis along the Z-axis direction by being wound around the crucible 61. A high frequency of 50 Hz to 1 MHz is applied to the induction coil 62 from the AC power source. The frequency is determined by the type of the evaporation material EM, the size of the crucible 61, and the like, and is typically set in a range of 1 kHz to 100 kHz.

  The induction coil 62 generates an eddy current (induction current) in the crucible 61 when high frequency power is applied, and heats the crucible 61 with the Joule heat (induction heating). Not only the crucible 61 but also the evaporation material EM housed in the housing portion 611 may be induction-heated at the same time. The heating temperature is not particularly limited, and is set to a temperature at which the vapor pressure of the evaporation material EM becomes a predetermined pressure by heat transfer from the crucible 61, heat radiation, or direct heating of the evaporation material EM. The predetermined pressure here is set to a pressure at which the evaporation rate of the evaporation material EM that can ensure the productivity of the vapor deposition apparatus is obtained, and specifically, 0.1 Pa to 1000 Pa.

  The induction coil 62 may have a water cooling structure in which cooling water can be circulated. As shown in FIG. 2, the evaporation source 6 may be provided with structural members 64 and 65 for integrally holding the crucible 61 and the induction coil 62 and for heat insulation of the crucible 61. The structural members 64 and 65 are made of a heat-insulating material, the structural member 64 is disposed between the support base 60 and the crucible 61, and the structural member 65 is disposed around the induction coil 62. These structural members 64 and 65 may be integrally formed with each other. Although not shown, a heat-resistant material for heat insulation between the crucible 61 and the induction coil 62 and for protection of the crucible 61 may be further provided.

  By the way, in recent years, there has been a demand for winding deposition on a base film that has been undercoated beforehand, a base film on which a device is formed, a base film having a very small heat capacity, a base film that is weak against heat load, or an extremely thin base film. Increasingly. For this reason, in order to reduce the influence of the base film due to heat radiation from the induction heating type evaporation source, a technique for suppressing the heat input of the base film and reducing the damage due to the thermal load is indispensable.

Therefore, in the present embodiment, the evaporation source 6 includes a shield member 63.
FIG. 3 is a side sectional view showing the relationship between the crucible 61 and the shield member 63, A shows the state where the shield member 63 is separated from the crucible 61, and B shows the shield member at the opening end 613 of the crucible 61. 63 shows a state where it is placed. FIG. 4 is a plan view of the shield member 63.

  The shield member 63 is made of a heat-insulating material, and is disposed on the outer peripheral side of the opening 612 of the crucible 61 so as to face the opening end 613 of the crucible 61. The shield member 63 has a function of blocking heat radiation from the opening end 613 of the crucible 61 to the film F on the main roller 4 by being arranged opposite to the opening end 613 of the crucible 61 in the Z-axis direction. Have.

  The shield member 63 is made of an appropriate material having heat resistance and heat shielding properties with respect to the heating temperature of the crucible 61 (for example, 1400 K or more), for example, water-cooled metal, oxide such as alumina, zirconia, magnesia, Alternatively, it is composed of a mixture of a plurality of oxides such as isolite. The shield member 63 is placed so as to be in contact with the opening end 613 of the crucible 61, but may be disposed so as to face the opening end 613 in a non-contact manner through an appropriate support mechanism.

  Typically, the shield member 63 is made of a material having a higher specific resistance than the crucible 61. Thereby, the temperature rise by the induction heating of the shield member 63 can be suppressed, and the heat shielding function by the shield member 63 can be ensured.

Specifically, the crucible 61 is made of graphite having a specific resistance value of 900 to 1250 μΩ · cm. In this case, the shield member 63 is made of a material having a high specific resistance value (eg, 10 ¹⁴ Ω · cm or more) mainly composed of an oxide such as alumina.

  Alternatively, the circuit in which the eddy current formed by the induction magnetic flux from the induction coil 62 in the shield member 63 flows has a higher resistance value than the circuit in the crucible 61 through which the eddy current formed by the induction magnetic flux from the induction coil 62 flows. It may be configured. In the induction heating method, the eddy current density is higher on the outer peripheral side than the inside of the crucible 61, and the eddy current density is higher on the outer peripheral side than the inner peripheral side of the shield member 63. Therefore, by comparing the outer peripheral sides of the crucible 61 and the shield member 63, the shape, thickness, material, or the like is selected so that the latter has higher electrical resistance than the former. Also good. For example, the shield member 63 may be made of a conductive material such as water-cooled metal, and the region where the eddy current density due to the induced magnetic flux generated from the induction coil 62 is high may be made of an electrically insulating material.

  As shown in FIGS. 3A, 3B, and 4, the shield member 63 has a circular through hole 631 that exposes the opening 612 of the crucible 61 to the outside. That is, as shown in FIG. 3A, the shield member 63 of the present embodiment is formed of an annular plate material having an inner diameter D2 larger than the opening diameter D1 of the opening 612 of the crucible 61. Since the inner diameter D2 of the shield member 63 is formed larger than the inner diameter (D1) of the crucible 61, the shield member 63 is stable without hindering the vapor flow Vm (see FIG. 2) of the evaporation material EM discharged from the opening 612. The film formation rate can be maintained.

For example, if the inner diameter of the shield member 63 is smaller than the inner diameter of the crucible 61, the vapor flow of the evaporation material EM contacts the inner peripheral portion of the shield member 63, thereby disturbing the vapor flow and forming the film F on the film F. It causes the film rate to decrease. Moreover, the vapor | steam which contacted the inner peripheral part of the shield member 63 accumulates on the said inner peripheral part, and thereby the internal diameter of the shield member 63 becomes small gradually, and this causes the steam flow to be further disturbed. As a result, a stable film formation rate cannot be maintained, and a film cannot be formed on the film F with a certain film quality.
On the other hand, according to this embodiment, since such a problem can be avoided, it can form into the film F stably with fixed film quality.

  The inner diameter D2 of the shield member 63 (opening diameter of the through hole 631) is larger than the opening diameter D1 of the opening 612 of the crucible 61 and the outer diameter D3 of the opening end 613 of the crucible 61 as shown in FIG. 3A. Set to a smaller size. When the inner diameter D2 of the shield member 63 is equal to or smaller than the opening diameter D1 of the opening 612, the vapor flow of the evaporation material discharged from the opening 612 may be disturbed. Further, when the inner diameter D2 of the shield member 63 is equal to or larger than the outer diameter D3 of the opening end 613, the shield member 63 cannot be disposed opposite to the opening end 613, and the heat radiation from the opening end 613 cannot be suppressed. .

  Typically, the inner diameter D2 of the shield member 63 is set to a size equal to or less than half the difference between the outer diameter D3 of the opening end 613 and the inner diameter (opening diameter D1 of the opening 612). Thereby, compared with the case where there is no shield member 63, it becomes possible to shield half or more of the total heat radiation amount from the opening edge part 613. FIG. The outer diameter D4 of the shield member 63 is typically set larger than the outer diameter of the open end 613 of the crucible 61.

  The thickness of the shield member 63 is not particularly limited as long as it is a thickness that does not inhibit the steam flow Vm while suppressing heat radiation from the opening end 613 of the crucible 61 to the film F on the main roller 4. The thickness can be determined as appropriate according to the constituent material of 63, the size of the crucible 61, the heating temperature, and the like. For example, the thickness is several mm to several tens of mm.

  Further, as described above, the shield member 63 is directly placed on the open end 613 of the crucible 61. In this case, it is preferable that the surface of the shield member 63 facing the opening end 613 of the crucible 61 (hereinafter also referred to as a facing surface) is rougher, whereby heat generation of the shield member 63 due to heat conduction from the crucible 61 can be suppressed. . From such a viewpoint, the shield member 63 may be formed of a molded body having a relatively large surface roughness such as a sintered body of oxide powder.

  Alternatively, as shown in FIG. 5, a plurality of legs 632 that contact the open end 613 of the crucible 61 may be provided on the facing surface of the shield member 63. According to such a configuration, the shield member 63 can be placed on the open end 613 of the crucible 61 with a smaller contact area, so that heat conduction from the crucible 61 to the shield member 63 can be suppressed.

(controller)
The vapor deposition apparatus 1 of the present embodiment further includes a controller 11 installed outside the vacuum chamber 7 (see FIG. 1). The controller 11 is configured by, for example, a computer including a CPU (Central Processing Unit) and a memory, and comprehensively controls each unit of the vapor deposition apparatus 1. The controller 11 performs, for example, control of the operation of the vacuum pump P, rotation driving and position control of each roller, control of the evaporation amount of the evaporation material EM in the evaporation source 6, and the like.

[Operation of evaporation system]
Next, a typical operation of the vapor deposition apparatus 1 configured as described above will be described.

  The inside of the film forming chamber 10 is evacuated by the vacuum pump P, whereby the inside of the vacuum chamber 7 is reduced to a predetermined pressure. The unwinding roller 2, the winding roller 3 and the main roller 4 rotate at respective predetermined speeds in the directions (clockwise) indicated by arrows in FIG. The film F is unwound continuously or intermittently clockwise by the unwinding roller 2.

  The film F unwound from the unwinding roller 2 is wound around the outer peripheral surface of the main roller 4 at a predetermined holding angle while being guided by the guide rollers 5A, 5B, 5C, and 5D. Then, the film F passes directly above the evaporation source 6 while receiving the cooling action (or heating action) by the main roller 4, and is then wound around the take-up roller 3 via the guide rollers 5E, 5F, 5G, and 5H. Taken.

  In the evaporation source 6, the crucible 61 is heated to a predetermined temperature by supplying an AC current to the induction coil 62 from an AC power source (not shown). The evaporating material EM accommodated in the crucible 61 is heated and evaporated by heat conduction or heat radiation from the crucible 61 or eddy current loss (Joule heat) caused by the induced magnetic flux generated from the induction coil 62. Thus, a steam flow Vm from the opening 612 of the crucible 61 toward the main roller 4 is formed (see FIG. 2). The vapor flow Vm adheres to and accumulates on the surface (film formation surface) of the film F conveyed at a predetermined speed on the peripheral surface of the main roller 4, thereby forming a vapor deposition film having a predetermined thickness on the film formation surface of the film F. Is done.

  In the present embodiment, as shown in FIGS. 3A and 3B, the evaporation source 6 includes a shield member 63 disposed opposite to the opening end 613 of the crucible 61, so that it is heated above the evaporation temperature of the evaporation material EM. The heat radiation from the open end 613 of the crucible 61 to the film F is effectively shielded. Thereby, since the damage by the thermal load of the film F reduces, it becomes possible to aim at the improvement of a yield.

  In particular, according to the present embodiment, since the input of the film F is suppressed by the shield member 63, not only a PET (polyethylene terephthalate) film but also an OPP (biaxially oriented polypropylene) film or CPP (CPP) that is weaker than the heat load. It is possible to form a stable film without causing thermal deformation such as wrinkles even in film formation on a non-axially stretched polypropylene) film or the like.

  Further, according to the present embodiment, since the inner diameter D2 of the shield member 63 is formed larger than the opening diameter D1 of the opening 612 of the crucible 61, the vapor flow Vm of the evaporation material EM discharged from the opening 612 is inhibited. It is possible to reach the film F on the main roller 4 without doing so. Thereby, since a stable film formation rate can be maintained, a thin film can be formed on the film F with a certain film quality, and the yield can be improved.

  Furthermore, as shown in FIG. 6, by arranging a plurality of evaporation sources 6 linearly or staggered along the film width direction (X-axis direction), a thin film having a uniform film quality over the width direction of the film F can be obtained. It becomes possible to form. Accordingly, it is possible to stably form a thin film having a uniform film quality over the entire area of the film F conveyed in the Y-axis direction.

[Experimental example]
Hereinafter, experimental examples performed by the present inventors will be described.

  Aluminum was used as the evaporation material EM, and an aluminum film having a thickness of 40 nm was formed on the surface of a PET film having a thickness of 12 μm as the film F. The crucible 61 is made of graphite having a specific resistance value of 900 to 1250 μΩ · cm, and has an inner diameter (opening diameter D1 of the opening 612) of 115 mm and an outer diameter (outer diameter D3 of the opening end 613) of 135 mm. . The distance between the evaporation source 6 and the film F was 270 mm, and the frequency of the high frequency power applied to the induction coil 62 was 9.9 kHz. The evaporation temperature of aluminum was about 1750K, and the temperature of the crucible 61 was 1900K.

  Under the above conditions, the amount of heat applied to the film F on the main roller 4 was measured by adding the amount of radiant heat from the aluminum surface accommodated in the crucible 61 and the amount of radiant heat from the upper part of the crucible 61 (opening end 613). Assuming that the amount of heat when the shield member 63 is not installed in the evaporation source is 100, the amount of heat applied to the film F when the shield member 63 having the above configuration is installed in the crucible 61 was 65. From this, it is confirmed that by installing the shield member 63 in the crucible 61, the heat load due to radiation from the evaporation source 6 to the film F can be reduced by 35% compared to the case where the shield member 63 is not installed. It was done.

Further, when the surface temperature of the film F on the main roller 4 was measured by setting the temperature of the refrigerant circulating inside the main roller 4 to −15 ° C., it was 50 ° C. when the shield member 63 was not installed on the crucible 61. In the case of the evaporation source 6 according to this embodiment in which the shield member 63 is installed on the crucible 61, the temperature was 45 ° C to 50 ° C. The conveyance speed at which the 40 nm aluminum film can be deposited by the evaporation source 6 without causing thermal damage to the film F was 1200 m / min.
Furthermore, when an aluminum film was similarly deposited using a polypropylene film as the film F, the yield was higher when the shield member 63 was installed on the crucible 61 than when the shield member 63 was not installed on the crucible 61. Was confirmed to be improved by 50% or more.

<Second Embodiment>
FIG. 7 is a schematic longitudinal sectional view showing an evaporation source according to the second embodiment of the present invention.
Hereinafter, the configuration different from the first embodiment will be mainly described, and the same configuration as the first embodiment will be denoted by the same reference numeral, and the description thereof will be omitted or simplified.

  The evaporation source 16 according to the present embodiment includes a first shield member 163 and a second shield member 164. The first shield member 163 has the same configuration as the shield member 63 in the first embodiment described above. The second shield member 164 is disposed on the outer peripheral side of the opening 612 of the crucible 61 so as to face the opening end 613 of the crucible 61 via the first shield member 163. Similar to the first shield member 163, the second shield member 164 is made of a material having heat insulation properties.

  In the present embodiment, the second shield member 164 having heat insulation is further disposed between the first shield member 163 and the main roller 4 (film F). The heat radiation blocking function can be further enhanced.

  Similar to the first shield member 163, the second shield member 164 is formed of an annular plate material and has a circular through-hole portion 1641 that exposes the opening 612 of the crucible 61. The diameter of the through hole portion 1641 is larger than the diameter of the through hole portion 1631 of the first shield member 163. Thereby, it is possible to reach the film F without disturbing the vapor flow of the evaporation material EM released from the opening 612 of the crucible 61.

  The second shield member 164 is placed in contact with the first shield member 163. Thereby, since the total thickness of the first and second shield members 163 and 164 can be reduced, the diameter of the through holes 1631 and 1641 of the shield members 163 and 164 can be reduced without increasing the diameter more than necessary. The flow can be prevented from being disturbed. Note that the present invention is not limited to this, and the second shield member 164 may be disposed on the first shield member 163 in a non-contact manner via an appropriate support mechanism. In addition, in FIG. 7, a plurality of legs that contact the upper surface of the first shield member 163 may be provided on the lower surface of the second shield member 164.

  The second shield member 164 may be made of a material having a higher specific resistance than that of the first shield member 163. Accordingly, the second shield member 164 is less likely to be induction-heated than the first shield member 163 by the induced magnetic flux generated from the induction coil 62, thereby suppressing the temperature rise of the second shield member 164 and the second The heat shielding function by the shield member 164 can be ensured.

  As described above, also in this embodiment, it is possible to obtain the same effects as those in the first embodiment.

  As mentioned above, although embodiment of this invention was described, this invention is not limited only to the above-mentioned embodiment, Of course, a various change can be added.

  For example, in the above embodiment, the shield members 63, 163, and 164 are formed of an annular plate material that faces the open end 613 of the crucible 61, but the shield members 63, 163, and 164 are open end portions of the crucible 61. It may be formed in a substantially cylindrical shape capable of covering not only 613 but also the outer peripheral surface of the crucible 61.

  The crucible 61 is not limited to a cylindrical shape, and may be a rectangular tube shape, and the opening 612 is not limited to a circular shape. In this case, the shape of the shield members 63, 163, and 164 may be changed as appropriate so as to correspond to the shape of the opening end 613 of the crucible 61.

  Furthermore, although the above embodiment demonstrated the example which applied this invention to the evaporation source in a winding-type vacuum evaporation apparatus as the evaporation source 6, it is not restricted to this, For example, the vapor deposition film on a semiconductor substrate or a glass substrate The present invention can also be applied to an evaporation source in a batch-type or in-line type vapor deposition apparatus capable of forming a film.

DESCRIPTION OF SYMBOLS 1 ... Deposition apparatus 2 ... Unwinding roller 3 ... Winding roller 4 ... Main roller 6, 16 ... Evaporation source 7 ... Vacuum chamber 61 ... Crucible 611 ... Accommodating part 612 ... Opening part 613 ... Opening end part 62 ... Inductive coil 63, 163 ... (first) shield member 164 ... second shield member EM ... evaporation material F ... film Vm ... vapor flow

Claims (7)

A crucible having an accommodating portion capable of accommodating an evaporating material, and an opening end portion formed with an opening for discharging the vapor of the evaporating material accommodated in the accommodating portion;
A coil for induction heating arranged around the crucible;
An evaporation source comprising: a first shield member that is disposed on the outer peripheral side of the opening portion so as to face the opening end portion and is made of a heat-insulating material. The evaporation source according to claim 1,
The opening has a circular shape;
The first shield member is constituted by an annular plate member having an inner diameter larger than the opening diameter of the opening. The evaporation source according to claim 1 or 2,
The first shield member is made of a material having a specific resistance higher than that of the crucible. The evaporation source according to claim 1 or 2,
The circuit through which an eddy current formed by the induced magnetic flux from the coil in the first shield member has a higher resistance than the circuit through which the eddy current formed by the induced magnetic flux from the coil is formed in the crucible. The evaporation source according to any one of claims 1 to 4,
An evaporation source further comprising a second shield member that is disposed on the outer peripheral side of the opening portion so as to face the opening end portion via the first shield member and is made of a heat-insulating material. The evaporation source according to claim 5,
The second shield member is made of a material having a higher specific resistance than the first shield member. A vacuum chamber;
A film conveying mechanism disposed inside the vacuum chamber, the unwinding roller for unwinding the film, and a winding roller for winding the film unwound from the unwinding roller;
An evaporation source for forming a deposited film on the film transported by the film transport mechanism,
The evaporation source is
A crucible having an accommodating portion capable of accommodating an evaporating material, and an opening end portion formed with an opening for discharging the vapor of the evaporating material accommodated in the accommodating portion;
A coil for induction heating arranged around the crucible;
A wind-up type vacuum deposition apparatus comprising: a first shield member that is disposed on the outer peripheral side of the opening portion so as to face the opening end portion and is made of a heat-insulating material.

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