Electron beam type vapor deposition unit

Abstract

To provide an electron beam type vapor deposition unit including: a hearth 2 including a plurality of recessed parts 21 for storing a vapor deposition material Em; an electron beam generation source 3; means 4 for shaping and deflecting an electron beam; and a hearth cover 5 and capable of easily performing work for charging the vapor deposition material Em and work for maintaining the hearth 2.SOLUTION: An electron beam type vapor deposition unit further includes: a movable part 6 for moving the hearth cover between a closed posture covering the upper part of the hearth and an open posture exposing all of the storing recessed parts; and a guide part 6 for guiding the hearth cover by self-weight at a normal position of matching the opening 51 of the hearth cover with any storing recessed part 21 in the vertical direction when returning the hearth cover to the closed posture from the open posture.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to an electron beam evaporation unit, and more specifically, to an electron beam evaporation unit that includes a hearth having a plurality of container recesses on the upper surface thereof for accommodating evaporation material, the container recesses being positioned on the same circumference, an electron beam generation source that generates an electron beam, and a shaping and deflection means that shapes and deflects the electron beam, and that irradiates the shaped and deflected electron beam onto the evaporation material in the container recesses to evaporate the evaporation material. [Background technology]

[0002] As an example of this type of electron beam evaporation unit, the one described in Patent Document 1 is known. This unit is provided with a hearth cover that has an opening that allows the exposure of the accommodation recess (hereinafter, referred to as the "first accommodation recess") located at the irradiation position, and covers the upper part of the hearth with a vertical gap, while the accommodation recess is being irradiated with the electron beam. During evaporation of the evaporation material by irradiation with the electron beam, contamination of the evaporation material accommodated in each accommodation recess is suppressed. In the above conventional example, a circulation passage for circulating cooling water is provided in the hearth cover to cool the hearth cover to a predetermined temperature. Then, the hearth cover is configured to capture so-called reflected electrons generated when the evaporation material in the first accommodation recess is irradiated with the electron beam by a magnetic circuit assembled below the hearth cover.

[0003] When an electron beam evaporation unit is installed in a vacuum chamber to perform evaporation (film formation) on a substrate to be processed, each of the recesses is filled with granular or ingot-shaped evaporation material, and then the hearth is rotated around its center to phase the first recess to the irradiation position. In this state, the first recess and the opening are aligned in the vertical direction, and only the first recess and the evaporation material filled therein are exposed. Then, an electron beam is generated in a vacuum chamber in a vacuum atmosphere, and the generated electron beam is irradiated to the evaporation material in the first recess while shaping and deflecting, thereby evaporating the evaporation material, and the evaporation material is deposited on the surface of the substrate to be processed installed in the vacuum chamber. When a predetermined amount of the evaporation material is evaporated (consumed) or when the evaporation material is changed, the hearth is rotated with the irradiation of the electron beam stopped, and, for example, another recess adjacent to the first recess is phased to the irradiation position. In this state, the evaporation material in the other recess is irradiated with the electron beam in the same manner as above to evaporate the evaporation material, and the evaporation material is deposited on the substrate to be processed. This operation is repeated to evaporate the deposition material in each of the accommodation recesses, and deposition onto the substrate to be processed is carried out in sequence.

[0004] Here, in the above-mentioned conventional example, the hearth cover is fixed to a base plate on which the electron beam generating source and the hearth are installed via a fastening means. Therefore, when filling (or refilling) each accommodation recess with the deposition material, it is necessary to fill each accommodation recess at the irradiation position with the deposition material while rotating the hearth in sequence, which significantly impairs the workability. In addition, during evaporation, the deposition material adheres to and accumulates on the wall surface of the accommodation recess including the opening portion tapering toward the upper surface. At this time, if the deposition material accumulates on the opening portion of the accommodation recess, for example, it may hinder the smooth rotation of the hearth, so a work to remove it (maintenance) is also required, but the workability is significantly poor if the work is done by removing the hearth cover each time. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 6195662 Summary of the Invention [Problem to be solved by the invention]

[0006] In view of the above, an object of the present invention is to provide an electron beam evaporation unit having a structure that allows easy filling of an evaporation material and easy maintenance of the hearth. [Means for solving the problem]

[0007] In order to solve the above problems, the electron beam evaporation unit of the present invention comprises a hearth having a plurality of accommodating recesses on its upper surface that are positioned on the same circumference and that have an electron beam generating source that generates an electron beam, and a shaping and deflection means that shapes and deflects the electron beam, and irradiates the shaped and deflected electron beam onto the evaporation material in the accommodating recesses to evaporate the evaporation material. The electron beam evaporation unit of the present invention is characterized in that it further comprises a hearth cover that covers the top of the hearth and has an opening that allows the exposure of the accommodating recesses located at the irradiation position, with a position of the hearth where any of the accommodating recesses is phased to a position immediately adjacent to the electron beam generating source in the radial direction as an irradiation position, a movable part that moves the hearth cover between a closed position that covers the top of the hearth and an open position that exposes all of the accommodating recesses, and a guide part that guides the hearth cover to the normal position by its own weight when the hearth cover is returned from the open position to the closed position, with a position of the hearth where the openings and the accommodating recesses are aligned in the vertical direction as the normal position.

[0008] According to the present invention, when the hearth cover is in the open position, all of the accommodation recesses are exposed, so that the work of filling the deposition material and the maintenance work on the hearth can be easily performed without having to rotate the hearth or remove the hearth cover each time, and the workability can be significantly improved. Moreover, by providing the guide part, the work of filling the deposition material and the maintenance work on the hearth can be completed simply by returning the hearth cover from the open position to the closed position.

[0009] In the present invention, the movable portion and the guide portion are preferably provided in a portion of the hearth cover covering the upper portion radially opposite to the opening portion across the center of the hearth, and are configured as a hinge mechanism that supports the hearth cover so as to be freely swingable. This makes it possible to easily realize a configuration that allows the hearth cover to be moved and guided between the closed position and the open position without interfering with other components. In this case, if the hearth cover is held in a position that stands upright in the vertical direction, there is no need to secure a retraction space for the hearth cover to be in the open position, which is advantageous.

[0010] In the present invention, a configuration may be adopted in which an annular protruding wall is provided on the lower surface of the hearth cover around the opening, and an annular seal structure is formed around the accommodating recess by the protruding wall when the hearth cover is swung back from the open position to the closed position. In this case, the lower surface of the protruding wall may be made to abut or come close to the upper surface of the hearth located around the accommodating recess. This anti-scattering seal structure prevents the evaporated material from flowing through the gap between the hearth and the hearth cover to other accommodating recesses when the evaporation material in the accommodating recess located at the irradiation position is evaporated by the electron beam irradiation, and as a result, contamination of the evaporation material can be further suppressed. In this case, an annular receiving groove may be provided around the accommodating recess to receive the protruding wall when the hearth cover is swung back from the open position to the closed position, and in the closed position of the hearth cover, the protruding wall may enter the receiving groove to form a labyrinth seal structure, or a seal structure without a labyrinth if the contact of the protruding wall with the receiving groove is permitted. In addition, when a ring-shaped protruding wall portion is provided on the underside of the hearth cover, it is preferable to further provide a pressing means for applying an upward pressing force to the underside of the hearth cover to swing the hearth cover to a rotation allowing position which allows rotation of the hearth.

[0011] Furthermore, in the present invention, when a circulation passage for circulating a refrigerant to cool the hearth cover is formed in the hearth cover, the hinge mechanism may have a pair of supports respectively provided on a base plate on which the hearth is installed, and a support shaft respectively fixed to each support, the hearth cover is attached to each support shaft via a bearing so as to be able to swing, an internal passage for allowing the passage of the refrigerant is formed in each support shaft, and each internal passage is connected to an inlet and an outlet of the circulation passage. In this way, a configuration for circulating the refrigerant in the circulation passage in the hearth cover can be realized by simply connecting an external pipe (e.g., a flexible metal hose) for supplying the refrigerant (cooling water) to one support shaft and an external pipe (e.g., a flexible metal hose) for discharging the refrigerant to the other support shaft. In this case, the hinge mechanism serves as a guide for guiding the hearth cover to a regular position by its own weight when the hearth cover is returned from the open position to the closed position, and serves to allow the hearth cover and the external pipe to swing freely relative to each other. As a result, even if the hearth cover is rocked, no stress is applied to the external piping, and therefore there is no risk of the external piping being damaged by repeated rocking of the hearth cover. [Brief description of the drawings]

[0012] [Figure 1] FIG. 2 is a perspective view showing the electron beam evaporation unit of the present embodiment with the hearth cover in a closed position. [Diagram 2] FIG. 2 is a perspective view showing the electron beam evaporation unit of the embodiment with the hearth cover in an open position. [Diagram 3] FIG. 2 is a side view of the electron beam evaporation unit shown in FIG. [Figure 4] FIG. 4 is a partially enlarged cross-sectional view illustrating a hinge mechanism and a hearth cover. [Diagram 5] 2A is a partially enlarged cross-sectional view taken along line Va-Va in FIG. 1, and FIG. 2B is a partially enlarged cross-sectional view taken when the hearth cover is swung to a rotation-permitting position. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, with reference to the drawings, an embodiment of the electron beam evaporation unit EB of the present invention, which is installed in a vacuum chamber of a vacuum evaporation device and evaporates an evaporation material Em to deposit (form a film) on a substrate to be processed, will be described. In the following, the directions perpendicular to each other in the plane of a base plate 1 described later are defined as the X-axis direction and the Y-axis direction, and terms indicating directions such as "up" and "down" are described based on FIG. 1, which shows the installation posture in the vacuum chamber (not shown).

[0014] 1 to 3, the electron beam evaporation unit EB includes a base plate 1 having a rectangular outline and elongated in the X-axis direction. A hearth 2 and an electron beam generating source 3 are arranged side by side in the X-axis direction on the base plate 1. Hereinafter, the electron beam generating source 3 side is referred to as the "front" and the hearth 2 side is referred to as the "rear" in the X-axis direction. The hearth 2 is made of a cylindrical member having good thermal conductivity such as copper, and has a plurality of accommodation recesses 21 for the evaporation material Em located on the same circumference on its upper surface. The hearth 2 is supported via a hearth shaft 22 provided on the base plate 1, and the hearth 2 can rotate by a predetermined rotation angle around its rotation axis via a motor (not shown) installed in the atmosphere. Hereinafter, the position of the hearth 2 where any of the accommodation recesses 21 is phased to a position immediately adjacent to the electron beam generating source 3 in the X-axis direction (radial direction) passing through the center of the hearth 2 is referred to as an irradiation position, and the one at this position is referred to as a first accommodation recess 21a. In addition, although not specifically shown or described, the hearth 2 is provided with a circulation path for a coolant (cooling water), and during deposition, the hearth 2 is cooled by circulating the coolant through the pipe 2a.

[0015] The electron beam generating source 3 includes a filament 31 and an anode plate 32 at earth potential. When the filament 31 is energized, thermoelectrons are emitted, and the thermoelectrons are accelerated by the potential difference with the anode plate 32 to generate an electron beam (not shown) that is drawn upward. The drawn electron beam is shaped and deflected into a predetermined shape by the shaping and deflection means 4, and the electron beam shaped into, for example, a spot shape is irradiated onto the deposition material Em in the first accommodation recess 21a. The shaping and deflection means 4 includes a pole piece 41 provided above the filament 31, and a pair of yokes 42 provided at an interval in the Y-axis direction so as to sandwich the trajectory of the electron beam from the front to the rear in the X-axis direction. The electron beam generating source 3 and the shaping and deflection means 4 are publicly known, and therefore further detailed description will be omitted. On the upper surface of the hearth 2, a plate-shaped hearth cover 5 made of, for example, copper is provided.

[0016] Referring also to FIG. 4, the hearth cover 5 has an opening 51 that allows only the first receiving recess 21a to be exposed. In order to move the hearth cover 5 between a closed position that covers the upper part of the hearth 2 and an open position that exposes all the receiving recesses 21, a hinge mechanism 6 that serves as both a movable part and a guide part in this embodiment is provided at the rear end part in the X-axis direction of the hearth cover 5 that covers the upper part of the hearth 2 on the radial opposite side of the opening 51 across the center (rotation axis) of the hearth 2. Here, the open position that exposes all the receiving recesses 21 means that the hearth cover 5 is not present above all the receiving recesses 21. Typically, the open position of the hearth cover 5 in FIG. 2 is an upright position, which will be described later, and the hinge mechanism 6 is configured to allow a change in position of approximately 90 degrees from the closed position to the open position. This can also improve the maintainability of the receiving recess 21 closest to the hearth cover 5. The hinge mechanism 6 may have a pair of supports 61 erected on the rear end side of the base plate 1. At the upper end of each support 61, a support shaft 62 is fixedly attached or detachably attached by a known method so as to penetrate through the upper end of each support and extend in the Y-axis direction. The support shaft 62 is made of, for example, stainless steel for corrosion resistance and to reduce gas emission on the vacuum atmosphere side. The support shaft 62 can be fixed to the support 61 by screws, clamps, fasteners, or clips (methods that do not require hand tools for fixing), or by adhesive or welding.

[0017] On both sides of the Y-axis direction of the hearth cover 5 located at the rear end side, a recess 63 is formed recessed inward, and a tip portion of a support shaft 62 located on the center side of the hearth cover 5 in the Y-axis direction from the support body 61 is fitted into the recess 63 via a seal member 64. In this embodiment, two O-rings are used as the seal member 64, but the present invention is not limited to this, and a contact seal such as a lip seal made of silicone or fluororesin can also be used. Note that vacuum grease may be applied to the contact surface between the O-ring or lip seal and the recess 63, or may be filled between the two O-rings, as necessary. On both sides of the Y-axis direction of the hearth cover 5, a bearing box 65 having a bearing (rolling bearing) 65a that supports the support shaft 62 is attached, and the hearth cover 5 is attached to each support shaft 62 via the bearing 65a so as to be freely swingable. In this case, the support shaft 62 located in the recess 63 may also serve as a sliding surface when the hearth cover 5 is swung, but the sliding surface may start from a region on the tip side of the seal member 64. In this way, the hinge mechanism 6 serves as a guide that guides the hearth cover 5 to the correct position by its own weight when the hearth cover 5 is returned from the open position to the closed position, and also serves to allow the hearth cover 5 to swing freely relative to the external piping described below.

[0018] If the hearth cover 5 is made of copper and there is a problem with lubrication even when the refrigerant is present, the surface of the support shaft 62 may be, for example, plated with fluororesin-impregnated nickel. In the case of sliding contact, the longer the contact surface, the lower the surface pressure, so the length of the support shaft 62 may be determined taking this into consideration. If the surface pressure is sufficient to constitute a sliding bearing, the function of the bearing 65a and the bearing box 65 that support the support shaft 62 described above (function as a rolling bearing) can be replaced by a sliding bearing composed of the recess 63 and the support shaft 62. In this case, since there is no protruding portion due to the bearing box 65 on the upper surface of the hearth cover 5, the configuration can be made even easier to maintain. In addition, if the portion that mainly receives the surface pressure is configured to be located closer to the center of the hearth cover 5 in the Y-axis direction than the seal member 64, the wear powder generated in the sliding bearing portion is collected by the circulation system on the refrigerant side, and the wear powder does not leak to the outside, and the sliding surface is cleaned, so that the life of the bearing can be improved.

[0019] Although not shown or described, the support 61 is provided with a stopper for restricting the swing range of the hearth cover 5 in order to avoid interference with the hearth 2 and the like, so that the hearth cover 5 is held in an upright position in the open position. An internal passage 62a is formed in each support shaft 62 over its entire length, allowing the passage of cooling water as a refrigerant. In this case, a substantially V-shaped circulation passage 52 is formed in the hearth cover 5, and the portion of the internal passage 62a located in the recess 63 is connected to the inlet 52a and the outlet 52b of the circulation passage 52. The open position of the hearth cover 5 by the stopper may be a position that is not located above the multiple storage recesses 21 of the hearth 2, and there is no problem even if it is other than the upright position described above. Under conditions where it is not necessary to avoid interference, the hearth cover 5 may be swung and held up to an inverted position (a position opened to about 180 degrees, assuming that the closed position is a position of about 0 degrees). In this way, maintenance can be easily performed even by an operator from the rear side in the state shown in FIG.

[0020] Nut members 62b are provided at the ends of the support shafts 62 protruding outward in the Y-axis direction from the support 61. External piping (not shown) extending from a chiller unit (not shown) is connected to each support 61 via the nut members 62b, so that the hearth cover 5 can be cooled by the cooling water circulating in the circulation passage 52. The method of fixing the connection of the external piping is not limited to this, and a hose band or connector method may be adopted. As the external piping, for example, a flexible metal hose is used in consideration of the ambient temperature during deposition, but the external piping is not limited to this. Regardless of the fixing method or external piping, the hinge mechanism 6 does not apply torsional stress due to the swinging of the hearth cover 5 (when fixed to the support 61, the connection does not rotate), and the probability of occurrence of a malfunction accompanied by leakage of the coolant is reduced, and improvement in maintainability is realized in terms of replacement frequency and inspection frequency. Further, a magnetic circuit 7 including a magnetic plate 71 made of a soft magnetic material and magnets 72 attached to both sides of the magnetic plate 71 in the Y-axis direction is disposed on the lower surface of the hearth cover 5 where the circulation passage 52 exists. This allows the hearth cover 5 to capture so-called reflected electrons that are generated when the deposition material Em in the first accommodation recess 21a located at the irradiation position is irradiated with an electron beam. The effect of cooling by the refrigerant is not only to efficiently capture the reflected electrons, but also to prevent the magnets 72 from being demagnetized by heat.

[0021] 5, the front lower surface of the hearth cover 5 is provided with an annular protruding wall portion 53 located around the opening 51. Correspondingly, the front upper surface of the hearth 2 is formed with an annular receiving groove 23 located around the first receiving recess 21a to receive the protruding wall portion 53. The position of the hearth cover 5 where the opening 51 and the receiving recess 21a match in the vertical direction is set as the normal position, and when the hearth cover 5 is swung from the open position to the closed position, the protruding wall portion 53 sinks (is received) into the receiving groove 23 under its own weight, forming a sealing structure for preventing scattering. When the configuration in which the protruding wall portion 53 sinks into the receiving groove 23 under its own weight is used as the guide portion, the contact portion of the wall and the groove may be guided by having a cross-sectional shape that forms a slope. This can improve the positional accuracy of the hearth cover 5 with respect to the hearth 2. In this embodiment, the height of the protruding wall portion 53 is set so that, for example, its lower end abuts against the bottom of the receiving groove 23 in the closed position, but the lower end may not abut against the receiving groove 23 to form a labyrinth seal structure. The closed position of the hearth cover 5 described in Fig. 1 and Fig. 5(a) is a stationary state formed by the weight of the hinge mechanism 6, which is a movable part and a guide part, and the hearth cover 5, and a reaction force from the bottom of the receiving groove 23 of the hearth 2. When a labyrinth seal structure is formed, the pressure rod described later receives the reaction force, and the pressure-receiving member 81 is configured to be stationary at a position where the distance required for the labyrinth is maintained.

[0022] However, when the protruding wall portion 53 enters the receiving groove 23 as described above, the protruding wall portion 53 interferes with the receiving groove 23 and the hearth 2 cannot be rotated. In this embodiment, a pressing means 8 is provided that applies an upward pressing force to the lower surface of the hearth cover 5 to swing the hearth cover 5 to a rotation allowing position that allows the hearth 2 to rotate (see FIG. 3). The pressing means 8 is composed of a pressure receiving member 81 attached to the lower surface of the front side of the hearth cover 5, and an air cylinder 82 that applies an upward pressing force to the pressure receiving member 81. When the front side of the hearth cover 5 is pushed up via the pressure receiving member 81 by the pressing rod of the air cylinder 82 from the closed position of the hearth cover 5 shown in FIG. 5(a), the hearth cover 5 swings to a rotation allowing position in which the protruding wall portion 53 is detached from the receiving groove 23 as shown in FIG. 5(b). This allows the hearth 2 to rotate. Two microswitches Ms are provided as detection means to detect whether the hearth cover 5 is in the closed position or the rotation-permitted position. The hearth cover 5 swings about a rotation axis determined by the hinge mechanism 6, and the relative positional relationship between the opening 51 and the accommodation recess 21 in the closed position is maintained by its function as a guide, and since bearings and contact seals are used, the torsional stress caused by the swing generated with each rotation of the hearth 2 is not transmitted to the external piping system. In other words, the probability of occurrence of a breakdown accompanied by a refrigerant leak due to production operation is reduced, and maintenance is improved in terms of the frequency of replacement and inspection.

[0023] According to the above embodiment, a configuration is realized in which the hearth cover 5 can be moved between the closed position and the open position. When the hearth cover 5 is in the open position, all the storage recesses 21 are exposed. Therefore, the filling operation of the deposition material Em and the maintenance operation of the hearth 2 can be easily performed without rotating the hearth 2 or removing the hearth cover 5, and the workability can be significantly improved. Moreover, the guide unit and the detection means make it possible to confirm the completion of the filling operation of the deposition material Em and the maintenance operation of the hearth by simply returning the hearth cover 5 from the open position to the closed position. In addition, when the deposition material Em in the first storage recess 21a is evaporated by irradiation of the electron beam, the evaporated material is prevented from flowing into the other storage recesses 21 through the gap between the hearth 2 and the hearth cover 5 as much as possible by forming a seal structure between the protruding wall portion 53 and the receiving groove 23 in the closed position of the hearth cover 5. As a result, the contamination of the deposition material Em can be further prevented. Furthermore, when the hearth cover 5 swings, no stress is applied to the external piping connected to the support shaft 62, so there is no risk of the external piping being damaged (leaking of refrigerant) due to repeated swinging of the hearth cover 5.

[0024] Although the embodiment of the present invention has been described above with reference to the drawings, various modifications are possible without departing from the scope of the technical concept of the present invention. In the above embodiment, the hinge mechanism 6 for swinging the hearth cover 5 has been described as an example of the movable part and the guide part, but the movable part is not limited to this as long as it can move the hearth cover 5 between the open position and the closed position. For example, the hearth cover 5 may be configured to move parallel to the same plane using a known mechanism. On the other hand, the guide part is not particularly limited as long as it can guide the hearth cover 5 to the correct position when it is returned from the open position to the closed position, and can be configured with, for example, a guide pin, a spigot, or a magnetic means. In addition, although not particularly illustrated and described, the guide part may be configured by engaging the protruding wall part 53 with the receiving groove 23, or by engaging the pressure receiving member 81 with the drive shaft of the air cylinder 82 when the hearth cover 5 is swung to the closed position. In this case, since the guide part exists below the upper surface of the hearth 2 in the direction of gravity, there is an effect of reducing the probability of sliding powder being mixed into the deposition material. The bottom surface of the receiving groove 23 may include a groove shape having a bottom surface that reaches the receiving groove 23 of each of the adjacent accommodating recesses 21. In other words, the technical concept of the receiving groove 23 also includes a shape having only a convex portion around the accommodating recess 21.

[0025] In addition, the hinge mechanism 6 as a movable part or a guide part has a pair of supports 61, and the support shaft 62 is fixed or detachably installed by a known method, but as long as the function as a guide part can be maintained, the present invention is not limited to this, and a method of installing (fixing) the support shaft 62 to the support 61 by only the weight of the hearth cover 5 may be adopted. Examples of a method of maintaining the relative positional relationship between the support shaft 62 and the support 61 by using its own weight (a method of functioning as a guide part) include the above-mentioned guide pin, spigot, magnetic means, and an installation means using a wedge effect in addition to these. Naturally, when an upward pressing force is applied to the lower surface of the hearth cover 5 by the pressing means (the rocking operation of the hearth cover 5 in the section reaching the rotation allowable position), the hearth cover 5 has its own weight that is greater than or equal to the level of functioning as a movable part and a guide part. In this way, if the hearth cover 5 is configured to be installed only by its own weight, the worker can freely open the hearth cover 5 during maintenance by exerting a force equivalent to its own weight on the hearth cover 5 (an additional advantage is that the degree of freedom to reach the open position can be determined without being based on the hinge mechanism 6 fixed to the support 61), which allows all the storage recesses 21 to be easily exposed, and the hinge mechanism 6 allows the hearth cover 5 to be opened without applying torsional stress to the external piping, thereby improving maintainability. In this configuration, the microswitch Ms, which is a means for detecting that the hearth cover 5 is in the closed position (normal state), is also used as an interlock signal for the electron beam irradiated to the deposition material Em in the first storage recess 21a, making it possible to prevent human error during maintenance. The weight of the hearth cover 5 also includes a configuration in which the weight is increased by a mechanism, magnetic force, or the like, within a range that does not impede the maintainability of the worker.

[0026] In the above embodiment, the hearth 2 is provided with the receiving groove 23, and the hearth cover 5 is provided with the protruding wall portion 53 to prevent contamination of the deposition material Em, but the present invention is not limited to this. For example, the hearth 2 or the hearth cover 5 may be provided with only the protruding wall portion 53, and in the closed position, the protruding wall portion 53 provided on the hearth 2 or the hearth cover 5 may be in contact with or close to the upper surface of the hearth 2 or the lower surface of the hearth cover 5 facing the protruding wall portion 53. In this case, it is preferable that the height (upward distance) of the protruding wall portion 53 around the accommodating recess 21 on the upper surface of the hearth 2 is equal to or higher than the relative height at which the protruding wall portion 53 of the hearth cover 5 cannot be seen directly in the state shown in FIG. 5(a). As a specific example, the height of the protruding wall portion 53 of the accommodating recess 21 may be set to be approximately the same as the upper position of the cylindrical portion present in the lower surface direction of the opening 51 of the hearth cover 5 in FIG. 5(a), thereby ensuring the relative height from the lower surface of the hearth cover 5. This prevents the evaporated material Em from getting into the seal structure as much as possible. In addition, although the embodiment has been described with the microswitch Ms provided to detect the closed position and the rotation permitting position, the present invention is not limited to this, and other known detection means may be used.

[0027] In the above embodiment, the hinge mechanism 6 for supporting the hearth cover 5 so as to be able to swing has been described as having the support 61 and the support shaft 62, but is not limited thereto. For example, the support 61 may be configured as a cooling water pipe having the rigidity to support the hearth cover 5. In addition, in the above embodiment, the open position in which all the storage recesses 21 are exposed is described as being able to improve maintainability by not having the hearth cover 5 above all the storage recesses 21, but this configuration is also effective for maintenance work that requires the removal and installation of the hearth 2. This is because the removal and installation of the hearth 2 generally requires a working space in the vertical direction, and there are obstacles in the horizontal direction. In a case where both of these purposes are to be achieved, it is preferable that the open position of the hearth cover 5 is configured so that the hearth cover 5 is not present above the hearth 2 in order to avoid interference with the hearth 2. [Explanation of symbols]

[0028] EB...electron beam evaporation unit, Em...evaporation material, 1...base plate, 2...hearth, 21...accommodating recess, 3...electron generation source, 4...shaping deflection means, 5...hearth cover, 52...circulation passage, 51...opening, 52a...inlet, 52b...outlet, 6...hinge mechanism (movable part and guide part), 61...support, 62...support shaft, 62a...internal passage, 65a...bearing, 53...projecting wall part (element forming sealing structure), 8...pressing means.

Claims

1. An electron beam evaporation unit including a hearth having a plurality of deposition material accommodation recesses on an upper surface thereof, the hearth being positioned on the same circumference, an electron beam generation source that generates an electron beam, and a shaping / deflection means that shapes and deflects the electron beam, the electron beam being shaped and deflected to irradiate the deposition material in the accommodation recesses to evaporate the deposition material, a hearth cover having an opening for exposing the accommodation recess located at the irradiation position, the hearth cover covering the upper part of the hearth, the hearth cover having an opening for exposing the accommodation recess located at the irradiation position, the hearth cover being provided with a hearth cover having an opening for exposing the accommodation recess located at the irradiation position, and a guide section that, when the hearth cover is returned from the open position to the closed position, guides the hearth cover to the correct position by its own weight, defining the position of the hearth cover where the opening and the storage recesses are aligned in the vertical direction as the correct position.

2. The electron beam evaporation unit according to claim 1, characterized in that the movable part and the guide part are provided in a part of a hearth cover which covers the upper part radially opposite the opening, sandwiching the center of the hearth, and are composed of a hinge mechanism which supports it so as to be freely swingable.

3. a ring-shaped protruding wall portion is provided on a lower surface of the hearth cover and positioned around the opening, 3. The electron beam evaporation unit according to claim 2, wherein an annular seal structure is formed around the accommodating recess by the protruding wall when the hearth cover is swung from the open position to the closed position.

4. 4. The electron beam evaporation unit according to claim 3, further comprising a pressing means for applying an upward pressing force to a lower surface of said hearth cover to swing said hearth cover to a rotation allowing position which allows rotation of the hearth.

5. 5. The electron beam evaporation unit according to claim 2, wherein a circulation passage for circulating a coolant to cool the hearth cover is formed in the hearth cover, the hinge mechanism has a pair of supports respectively provided on a base plate on which the hearth is placed, and a support shaft respectively fixed to each of the supports, and a hearth cover is attached to each support shaft via a bearing so as to be freely swingable; 1. An electron beam evaporation unit comprising: an inner passage for allowing a coolant to pass through each support shaft; and each inner passage being connected to an inlet and an outlet of a circulation passage, respectively.

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