Soft x-ray shielding sheet unit and method for manufacturing same

Abstract

Provided are a soft X-ray shielding sheet unit suitable for mass production and a method for manufacturing the same. The soft X-ray shielding sheet unit has an insulating layer between a soft X-ray shielding sheet and a soft X-ray shielding sheet holder. A soft X-ray shielding sheet unit (1) comprises: a soft X-ray shielding sheet (20) in which a flow path (44) through which air passes but soft X-rays do not pass is formed; and a soft X-ray shielding sheet holder (10) that supports the soft X-ray shielding sheet (20). The soft X-ray shielding sheet holder (10) has an intermediate plate (16) having formed therein a through-hole (18) that accommodates the soft X-ray shielding sheet (20); and a pair of outer plates (12) that sandwich the soft X-ray shielding sheet (20) and the intermediate plate (16) from both sides and that have formed therein a through-hole (14) through which air passes. The area of contact between the soft X-ray shielding sheet (20) and the soft X-ray shielding sheet holder (10) is insulated by an insulating coating (60).

Description

Soft X-ray shielding sheet unit and manufacturing method thereof

[0001] The present invention relates to a soft X-ray shielding sheet unit and a manufacturing method thereof, and more particularly to a soft X-ray shielding sheet unit suitable for mass production and a manufacturing method thereof.

[0002] It has been known for some time that in the manufacturing processes of semiconductors, liquid crystals, and organic EL devices, static electricity builds up on the surfaces of semiconductor substrates, liquid crystal substrates, and organic EL substrates during their processing and handling, causing problems such as damage to the circuits of the semiconductor substrates, liquid crystal substrates, and organic EL substrates. Furthermore, the static electricity on each substrate also causes problems such as dust adhesion to the surface.

[0003] To address these problems, electrostatic removal devices that generate ions to prevent and remove static electricity from the substrate surface are installed in semiconductor, liquid crystal, and organic EL manufacturing equipment.Static removal devices include corona discharge type electrostatic removal devices that ionize the air with high voltage, and soft X-ray type electrostatic removal devices that ionize the air by irradiating it with soft X-rays.

[0004] Corona discharge static electricity removal devices generate particles from the electrodes during discharge, while soft X-ray static electricity removal devices do not generate particles, but leakage of soft X-rays can have an adverse effect on the human body, and each method has its own drawbacks.

[0005] To address this issue, soft X-ray static electricity removers have been developed that extract only ionized air and do not leak soft X-rays to the outside, but their structure is complicated.To address this issue, the inventors previously proposed a soft X-ray static electricity remover having a soft X-ray shielding sheet that can prevent the soft X-rays from leaking from the discharge port with a simple structure by limiting the number of times that the soft X-rays entering from the supply port collide with the passage on their way to the discharge port to at least three times, thereby attenuating and eliminating the soft X-rays.(Patent Document 1)

[0006] Furthermore, as semiconductors and the like become increasingly delicate, there is a growing demand for a further increase in the amount of ionized air emitted, as well as the ability to adjust the amount of positive and negative ions.The inventors therefore proposed a soft X-ray static electricity removal device that insulates the soft X-ray shielding sheet from the container used to ionize the air with soft X-rays, thereby increasing the amount of ions emitted without trapping the ions in the soft X-ray shielding sheet, and that can adjust the amount of positive and negative ions emitted by applying a voltage to the soft X-ray shielding sheet and the container (Patent Document 2).

[0007] International Publication No. WO2008 / 023727 Pamphlet Japanese Patent No. 7262299

[0008] In the invention disclosed in Patent Document 2, an insulating layer made of ceramic is provided between the soft X-ray shielding sheet and the container, thereby insulating the soft X-ray shielding sheet from the container. That is, an insulating layer block made of ceramic is provided between the soft X-ray shielding sheet and a soft X-ray shielding sheet holder that supports the soft X-ray shielding sheet. However, the soft X-ray shielding sheet is small, and the ceramic insulating layer block is also small. When a brittle material such as ceramic is made small, i.e., thin, it becomes easily broken. Furthermore, disposing and fixing the ceramic insulating layer block between the soft X-ray shielding sheet and the soft X-ray shielding sheet holder, which are typically made of metal such as stainless steel, requires a complicated process, resulting in labor-intensive manufacturing, increased costs, and difficulty in mass production.

[0009] Therefore, an object of the present invention is to provide a soft X-ray shielding sheet unit having an insulating layer between a soft X-ray shielding sheet and a soft X-ray shielding sheet holder, which is suitable for mass production, and to provide a method for manufacturing the soft X-ray shielding sheet unit suitable for mass production.

[0010] In order to solve the above problems, as shown in FIGS. 1 and 4 , a soft X-ray shielding sheet unit 1 according to a first aspect of the present invention comprises: a soft X-ray shielding sheet 20 having formed therein flow paths 44 through which air passes but soft X-rays do not; and a soft X-ray shielding sheet holder 10 supporting the soft X-ray shielding sheet 20, the soft X-ray shielding sheet holder 10 having an intermediate plate 16 having formed therein through holes 18 for accommodating the soft X-ray shielding sheet 20; and a pair of outer plates 12 sandwiching the soft X-ray shielding sheet 20 and the intermediate plate 16 from both sides and having formed therein through holes 14 through which air passes, and the soft X-ray shielding sheet unit 10 is insulated by an insulating coating 60 at the contact portion between the soft X-ray shielding sheet 20 and the soft X-ray shielding sheet holder 10.

[0011] With this configuration, in the soft X-ray shielding sheet unit, the soft X-ray shielding sheet and the soft X-ray shielding sheet holder are insulated by the insulating coating, so by using the soft X-ray shielding sheet unit, the soft X-ray shielding sheet is insulated from the container.The soft X-ray shielding sheet is positioned in the through-hole of the intermediate plate and sandwiched between the outer plates from both sides, and at this time, the soft X-ray shielding sheet and the soft X-ray shielding sheet holder are insulated by the insulating coating, so the insulating coating is not damaged, the manufacturing process is easy, costs are kept low, and the soft X-ray shielding sheet unit is suitable for mass production.

[0012] 1, the soft X-ray shielding sheet unit 1 according to the second aspect of the present invention has a portion of the soft X-ray shielding sheet holder 10 that comes into contact with the soft X-ray shielding sheet 20 covered with an insulating coating 60. With this configuration, the soft X-ray shielding sheet and the soft X-ray shielding sheet holder can be insulated from each other by covering the portion of the soft X-ray shielding sheet holder that comes into contact with the soft X-ray shielding sheet with an insulating coating, thereby achieving insulation with a simple structure.

[0013] 1 and 4, the soft X-ray shielding sheet unit 1 according to the third aspect of the present invention has the portion of the soft X-ray shielding sheet 20 that contacts the soft X-ray shielding sheet holder 10 covered with an insulating coating. With this configuration, the soft X-ray shielding sheet and the soft X-ray shielding sheet holder can be insulated by covering the portion of the soft X-ray shielding sheet that contacts the soft X-ray shielding sheet holder with an insulating coating, so that insulation can be achieved with a simple structure.

[0014] 1, for example, the soft X-ray shielding sheet unit 1 according to the fourth aspect of the present invention has the outer plate 12 at least partially protruding from a portion corresponding to the through-hole 18 formed in the intermediate plate 16. With this configuration, the soft X-ray shielding sheet can be held in the through-hole by the portion of the outer plate protruding from the portion corresponding to the through-hole of the intermediate plate, and therefore the intermediate plate and the soft X-ray shielding sheet can be sandwiched and supported by the outer plate with a simple structure.

[0015] Furthermore, in the soft X-ray shielding sheet unit 1 according to the fifth aspect of the present invention, the insulating coating 60 is a fluorine-based coating. With this configuration, the insulating coating is a fluorine-based coating, which has excellent heat resistance and chemical resistance, allows heating during the manufacturing process, facilitating manufacturing, and prevents dust from scattering even when air flows.

[0016] Furthermore, in the soft X-ray shielding sheet unit 1 according to the sixth aspect of the present invention, the insulating coating 60 is a ceramic coating. With this configuration, the insulating coating is a ceramic coating, which has excellent heat resistance at high temperatures, allows heating such as laser welding during the manufacturing process, and facilitates manufacturing, while preventing dust from scattering even when air flows.

[0017] In order to solve the above problems, a manufacturing method of a soft X-ray shielding sheet unit 1 according to a seventh aspect of the present invention includes, as shown in FIG. 4 , a step of coating the intermediate plate 16 with an insulating agent, a step of coating the outer plate 12 with an insulating agent, a step of stacking the intermediate plate 16 and one of the outer plates 12, a step of arranging a soft X-ray shielding sheet 20 in the through hole 18 of the intermediate plate 16 stacked on the outer plate 12, a step of further stacking the outer plate 12 on the intermediate plate 16 on which the soft X-ray shielding sheet 20 is placed to sandwich the soft X-ray shielding sheet 20 and the intermediate plate 16, and a step of integrating the stacked intermediate plate 16 and the pair of outer plates 12.

[0018] With this configuration, the intermediate plate and the outer plates are coated with an insulating agent, the intermediate plate and one outer plate are stacked together to arrange the soft X-ray shielding sheet, and the outer plates are further stacked together to sandwich the soft X-ray shielding sheet and intermediate plate between the outer plates, thereby integrating the intermediate plate and the pair of outer plates, thereby manufacturing a soft X-ray shielding sheet unit.This method of manufacturing a soft X-ray shielding sheet unit does not damage the insulating coating, is easy to manufacture, keeps costs low, and is suitable for mass production.

[0019] In addition, in the manufacturing method of the soft X-ray shielding sheet unit 1 according to the eighth aspect of the present invention, for example, as shown in Fig. 4, an outer plate / intermediate plate assembly 15, which is made by stacking an intermediate plate 16 and one of the outer plates 12, is coated with an insulating agent, and the other outer plate is also coated with an insulating agent. With this configuration, the number of coating steps can be reduced and the area to be coated is also reduced compared to coating the intermediate plate and the pair of outer plates separately, making the manufacturing process easier and reducing costs.

[0020] In the integration step in the manufacturing method of the soft X-ray shielding sheet unit 1 according to the ninth aspect of the present invention, the stacked intermediate plate 16 and the pair of outer plates 12 are welded together at a welding W, as shown in Fig. 4. This configuration eliminates the need for complicated operations such as screwing or crimping, making the manufacturing process easier and less expensive.

[0021] In order to solve the above problem, a manufacturing method of a soft X-ray shielding sheet unit 1 according to a tenth aspect of the present invention includes the steps of masking the surface of the soft X-ray shielding sheet 20 where the flow paths 44 open, coating the masked soft X-ray shielding sheet 20 with an insulating agent, removing the masking, overlapping the intermediate plate 16 and one of the outer plates 12, placing the soft X-ray shielding sheet 20 from which the masking has been removed in the through-hole 18 of the intermediate plate 16 overlapped with the outer plate 12, overlapping the outer plate 12 on the intermediate plate 16 on which the soft X-ray shielding sheet 20 has been arranged to sandwich the soft X-ray shielding sheet 20 and the intermediate plate 16, and integrating the overlapped intermediate plate 16 and the pair of outer plates 12.

[0022] With this configuration, the edges of the soft X-ray shielding sheet where the flow paths are not open are coated with an insulating agent, the soft X-ray shielding sheet is positioned by overlapping the intermediate plate and one outer plate, and the outer plate is further overlapped to sandwich the soft X-ray shielding sheet and intermediate plate between the outer plates, and the intermediate plate and the pair of outer plates are integrated, thereby manufacturing a soft X-ray shielding sheet unit.This method of manufacturing a soft X-ray shielding sheet unit does not damage the insulating coating, is easy to manufacture, keeps costs low, and is suitable for mass production.

[0023] In the integration step in the manufacturing method of the soft X-ray shielding sheet unit 1 according to the eleventh aspect of the present invention, the stacked intermediate plate 16 and the pair of outer plates 12 are welded together at a welding W, as shown in Fig. 4. This configuration eliminates the need for complicated operations such as screwing or crimping, making the manufacturing process easier and less expensive.

[0024] According to the soft X-ray shielding sheet unit of the present invention, the contact portion between the soft X-ray shielding sheet and the soft X-ray shielding sheet holder is insulated by an insulating coating, so that the insulating layer block is not damaged, the manufacturing process is easy, costs are kept low, and the soft X-ray shielding sheet unit is suitable for mass production. Also, according to the manufacturing method of the soft X-ray shielding sheet unit of the present invention, the soft X-ray shielding sheet unit can be manufactured by coating the intermediate plate and the outer plates with an insulating agent or coating the peripheral edge of the soft X-ray shielding sheet where the flow path is not opened with an insulating agent, overlapping the intermediate plate and one outer plate to arrange the soft X-ray shielding sheet, and further overlapping the outer plate to integrate the intermediate plate and the pair of outer plates. Therefore, the manufacturing method of the soft X-ray shielding sheet unit is suitable for mass production, so that the insulating layer block is not damaged, the manufacturing process is easy, costs are kept low, and the soft X-ray shielding sheet unit is suitable for mass production.

[0025] 1A and 1B are diagrams for explaining the soft X-ray shielding sheet, in which (a) is a plan view of the outer plate, the intermediate plate, and the soft X-ray shielding sheet seen separately, and (b) is a cross-sectional view of an assembled soft X-ray shielding sheet unit. A cross-sectional view for explaining the flow path of air in the soft X-ray shielding sheet. An exploded perspective view of the soft X-ray shielding sheet for explaining the flow path of the soft X-ray shielding sheet. A diagram for explaining a manufacturing method of the soft X-ray shielding sheet, in which (a) shows the process of coating the outer plate / intermediate plate assembly and arranging the soft X-ray shielding sheet, (b) shows the process of coating and stacking another outer plate, and (c) shows the process of welding the stacked intermediate plate and the pair of outer plates. Note that the insulating coating is omitted in (c).

[0026] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In each drawing, identical or corresponding devices are designated by the same reference numerals, and duplicated explanations will be omitted. First, a soft X-ray shielding sheet unit 1 of the present invention will be described with reference to FIG.

[0027] FIG. 1( a) shows the main components of a soft X-ray shielding sheet unit 1. The soft X-ray shielding sheet unit 1 includes a soft X-ray shielding sheet 20 having flow paths 44 formed therein that allow air to pass but not soft X-rays to pass therethrough, an intermediate plate 16 having through holes 18 formed therein for accommodating the soft X-ray shielding sheet 20, and a pair of outer plates 12 having through holes 14 formed therein so as not to block the flow paths 44 in the soft X-ray shielding sheet 20. The soft X-ray shielding sheet 20 will be described in detail elsewhere. Note that although the through holes 14 and 18 are shown as circular in FIG. 1 , they may have any shape. When the through holes 14 and 18 are circular, the diameter of the through holes 14 is made smaller than the diameter of the through holes 18, so that the outer plates 12 protrude from the portions of the intermediate plate 16 that correspond to the through holes 18. Note that the outer plate 12 overhanging the portion corresponding to the through hole 18 of the intermediate plate 16 means that at least a portion of the periphery of the through hole 14 of the outer plate 12 is located above the through hole 18 when the outer plate 12 and the intermediate plate 16 are stacked on top of each other. Preferably, the soft X-ray shielding sheet 20 can be stably sandwiched by overhanging at two or more locations. Also, although one through hole 18 and one through hole 14 are shown to be formed in one intermediate plate 16 and one outer plate 12, a plurality of through holes 18 and a plurality of through holes 14 may be formed therein.

[0028] The through-holes 18 formed in the intermediate plate 16 have substantially the same shape and dimensions as the outer shape of the soft X-ray shielding sheet 20. The through-holes 18 having substantially the same shape and dimensions as the outer shape of the soft X-ray shielding sheet 20 means that the soft X-ray shielding sheet 20 can be placed in the through-holes 18 on the same plane and will not rattle when placed. Some gaps are permitted. However, excessively large gaps must be avoided to allow air 100 passing through the soft X-ray shielding sheet unit 1 to pass through. Furthermore, the thicknesses of the intermediate plate 16 and the soft X-ray shielding sheet 20 are also made substantially the same so that, when sandwiched between the outer plates 12, air 100 passing through the soft X-ray shielding sheet 20 or the gap between the intermediate plate 16 and the outer plate 12 will not pass through.

[0029] At least a part of the outer plate 12 in which the through hole 14 is formed protrudes into a portion corresponding to the through hole 18 of the intermediate plate 16. That is, when the outer plate 12 and the intermediate plate 16 are overlapped, there is a portion of the outer plate 12 that protrudes above the through hole 18 of the intermediate plate 16. Therefore, when the outer plate 12, the intermediate plate 16, and the soft X-ray shielding sheet 20 are overlapped, the soft X-ray shielding sheet 20 arranged in the through hole 18 of the intermediate plate 16 is prevented from falling off from the through hole 18 by the outer plate 12.

[0030] The pair of outer plates 12 usually have the same shape and size, but may have different shapes and sizes. However, it is preferable that the pair of outer plates 12 and the intermediate plate 16 have the same outer dimensions. This is because they can be easily combined and integrated, and the outer shape of the soft X-ray shielding sheet unit 1 becomes simple, making it easier to handle.

[0031] The portion of the soft X-ray shielding sheet holder 10, which is made up of the overlapping intermediate plate 16 and the pair of outer plates 12, that comes into contact with the soft X-ray shielding sheet 20 is covered with an insulating coating, although the insulating coating is not shown in FIG. 1( b ). In other words, the soft X-ray shielding sheet holder 10 and the soft X-ray shielding sheet 20 are insulated from each other. The soft X-ray shielding sheet unit 1 is typically used at the ionized air outlet of a soft X-ray type electrostatic eliminator (not shown). Insulating the soft X-ray shielding sheet 20 from the soft X-ray shielding sheet holder 10 insulates the soft X-ray shielding sheet 20 from a container that irradiates soft X-rays to ionize the air. This increases the amount of ionized air emitted, and further facilitates the manufacture of a soft X-ray type electrostatic eliminator that can adjust the amount of positive ions / negative ions.

[0032] The insulating coating may be formed by coating with an insulating agent. A fluorine-based coating formed with a fluorine-based insulating agent is preferred as the insulating coating because it has excellent heat resistance and chemical resistance. In particular, in the manufacturing processes of semiconductors, liquid crystals, and organic EL devices, it is often required to prevent even the smallest amount of dust from entering, so a fluorine-based insulating agent that is less likely to generate dust is preferred. Specifically, PFA (perfluoroalkoxyalkane polymer), PTFE (polytetrafluoroethylene), FEP (perfluoroethylenepropene copolymer), etc. are preferably used.

[0033] Alternatively, the insulating coating may be formed of a ceramic coating. A ceramic coating can withstand high temperatures, particularly temperatures exceeding 380°C, and therefore, for example, it is possible to form the soft X-ray shielding sheet holder 10 by laser welding the outer plate 12 and the intermediate plate 16, both of which are coated with the insulating coating 60, thereby facilitating manufacturing. Another advantage of using a ceramic coating is that it is less likely to generate dust. Examples of ceramics that can be used for the ceramic coating include, but are not limited to, oxides such as alumina and silica, and nitrides such as silicon nitride.

[0034] 1(b), a soft X-ray shielding sheet unit 1 is configured in which a soft X-ray shielding sheet 20 is placed in the through-hole 18 of the intermediate plate 16 and both sides of the sheet are sandwiched between a pair of outer plates 12, thereby supporting the soft X-ray shielding sheet 20 with the soft X-ray shielding sheet holder 10. The soft X-ray shielding sheet unit 1 configured in this manner does not require a ceramic insulating layer block, so the insulating layer is not damaged, the manufacturing process is simple, costs are kept low, and it is suitable for mass production.

[0035] In the above description, in the soft X-ray shielding sheet unit 1, the portion of the soft X-ray shielding sheet holder 10 that contacts the soft X-ray shielding sheet 20 is covered with the insulating coating 60. However, the portion of the soft X-ray shielding sheet 20 that contacts the soft X-ray shielding sheet holder 10 may also be covered with the insulating coating. That is, the peripheral portion of the soft X-ray shielding sheet 20 is covered with the insulating coating. Note that the peripheral portion is covered so that the flow path 44 opens to the surface and allows ionized air to flow. The flow path 44 is basically small, and it is difficult to cover the inside of the flow path 44 with an insulating coating. Furthermore, since the insulating coating may deteriorate and generate dust if exposed to soft X-rays, it is desirable to form the insulating coating only on the portion sandwiched between the outer plates 12 and not exposed to soft X-rays, particularly on the surface upstream of the ionized air. That is, it is preferable not to form the insulating coating in the area corresponding to the through-hole 14.

[0036] Next, the soft X-ray shielding sheet 20 and the flow path 44 through which air ionized by soft X-rays (ionized air) 100 passes will be described with reference to FIGS. 2 and 3 . FIG. 2 is a cross-sectional view of the soft X-ray shielding sheet 20 near the flow path 44, and FIG. 3 is an exploded perspective view of the same. The soft X-ray shielding sheet 20 is formed by stacking and fixing three sheets: a first outer layer sheet 30 made of a material that is opaque to soft X-rays 92; an intermediate layer sheet 34 made of a material that is opaque to soft X-rays 92; and a second outer layer sheet 40 made of a material that is opaque to soft X-rays 92. Here, examples of materials that are opaque to soft X-rays include, but are not limited to, metals. Metals are suitable for the soft X-ray shielding sheet 20 because they can block the passage of soft X-rays 92 even when they are thin and can be easily formed thin. The method of stacking and fixing the sheets is not particularly limited. The first outer sheet 30 has a supply port 32 through which the ionized air 100 enters the soft X-ray shielding sheet 20. The middle sheet 34 has ionized air inlet openings 36 at both ends, forming ionized air passages 38. The second outer sheet 40 has an outlet port 42 through which the ionized air 100 is released.

[0037] In this embodiment, the first outer sheet 30 has two supply ports 32 that are spaced apart from each other in the first outer sheet 30. The ionized air passages 38 of the intermediate sheet 34 have ionized air inlet openings 36 that are opened at positions that communicate with the supply ports 32 of the first outer sheet 30, and are formed to communicate with each ionized air inlet opening 36. The second outer sheet 40 has an outlet port 42 that is opened at a position that communicates with the ionized air passages 38 of the intermediate sheet 34.

[0038] When the first outer layer sheet 30, intermediate layer sheet 34, and second outer layer sheet 40 formed as described above are laminated and fixed together, the supply ports 32 of the first outer layer sheet 30 communicate with the ionized air inlet openings 36 of the intermediate layer sheet 34, and further the ionized air passage 38 of the intermediate layer sheet 34 communicates with the outlet port 42 of the second outer layer sheet 40 at the center of the ionized air passage 38, thereby forming a flow path 44. The soft X-ray shielding sheet 20 may have one or more flow paths 44 formed therein.

[0039] The ionized air passage 38 is provided with a bent portion 39 that is bent 90 degrees in a plane so that the number of collisions of the soft X-rays 92 with the inner surface 41 of the second outer sheet 40 and the inner surface 31 of the first outer sheet 30 increases while the soft X-rays 92 enter from the supply port 32 and reach the discharge port 42, causing the soft X-rays 92 to attenuate and disappear.

[0040] Furthermore, each bent portion 39 of the ionized air passage 38 is formed with a curved surface 37 to reduce the fluid resistance of the ionized air 100, allowing the ionized air 100 to reach the outlet 42 in a short time and suppressing the recombination of positive ions and negative ions. That is, the ionized air passage 38 has at least one bent portion 39 that bends 90 degrees on a plane, and aims to eliminate the soft X-rays 92 by collision with the inner surface, i.e., the passage. The shape of the ionized air passage 38 may be other shapes. A shape that reduces the fluid resistance of the ionized air 100 while increasing the number of collisions of the soft X-rays 92 with the passage is preferred.

[0041] The operation of the soft X-ray shielding sheet 20 configured as described above will be explained with reference to Fig. 2. Inside a container (not shown) located upstream of the soft X-ray shielding sheet 20, ionized air 100, which has been ionized into positive ions and negative ions by soft X-rays 92, is in a pressurized state as outside air is sent into the container. Therefore, the ionized air 100 flows from the supply port 32 through the ionized air inlet opening 36 and ionized air passage 38 and is discharged from the discharge port 42 to the downstream side of the soft X-ray shielding sheet 20.

[0042] On the other hand, soft X-rays 92 enter through each supply port 32, travel straight, and then pass through the ionized air inlet opening 36, the ionized air passage 38, and the outlet 42. As shown in FIG. 2 , they collide with the inner surface 41 of the second outer sheet 40, the inner surface 31 of the first outer sheet 30, or the curved surface 37 of the bent portion 39, preventing them from traveling straight. Upon collision with the inner surfaces 31, 41, etc., the soft X-rays 92 are attenuated and eventually almost completely extinguished, preventing dangerous soft X-rays 92 from leaking from the outlet 42. For the soft X-rays 92 to be attenuated and almost completely extinguished, they preferably collide with the inner surfaces 31, 41, etc., three or more times. To achieve this, the cross-sectional size and length of the flow path 44 and the number of bent portions 39, i.e., the path of the ionized air passage 38, are designed. The number of sheets constituting the soft X-ray shielding sheet 20 may be four or more, instead of three.

[0043] The ionized air 100 introduced from the supply port 32 passes through the ionized air passage 38 and reaches the outlet 42. The bent portion 39 of the ionized air passage 38, which is provided to prevent leakage of soft X-rays 92, is formed into a curved surface 37, thereby reducing fluid resistance and allowing the ionized air 100 to reach the outlet 42 in a short time. In particular, it is preferable that the ionized air 100 can pass through the soft X-ray shielding sheet 20 in a short time so as to suppress recombination of positive ions and negative ions, and the path of the flow path 44 is made short. Therefore, a large amount of ions are released downstream from the outlet 42.

[0044] Next, a manufacturing method of the soft X-ray shielding sheet unit 1 will be described with reference to FIG. 4 . As shown in FIG. 4( a), first, an intermediate plate 16 is placed on one outer plate 12 (outer plate 12a) to form an outer plate / intermediate plate assembly 15. Then, the entire surface of the outer plate / intermediate plate assembly 15 is coated with an insulating agent to form an insulating coating 60. As shown in FIG. 4( b), the entire surface of the other outer plate 12 (outer plate 12b) is also coated with an insulating agent to form an insulating coating 60. A soft X-ray shielding sheet 20 is placed in the through-hole 18 of the intermediate plate 16 of the coated outer plate / intermediate plate assembly 15. Then, the outer plate / intermediate plate assembly 15 is placed on the other coated outer plate 12b. Then, as shown in FIG. 4( c), the outer edges of the stacked outer plate 12a, intermediate plate 16, and outer plate 12b are welded together by welding W to manufacture the soft X-ray shielding sheet unit 1. Alternatively, the outer plate 12a, the intermediate plate 16 may be placed on top of the outer plate 12a to form the outer plate / intermediate plate assembly 15, and the outer edges of the assembly may be welded together. Then, the soft X-ray shielding sheet 20 may be placed on top of the outer plate 12b, and the outer edges of the outer plate / intermediate plate assembly 15 and the outer plate 12b may be welded together to form the outer plate 12a, the intermediate plate 16, and the outer plate 12b into a single unit.

[0045] When manufactured in this manner, the soft X-ray shielding sheet unit 1 can be manufactured by placing the soft X-ray shielding sheet 20 in the through hole 18 of the intermediate plate 16, sandwiching it between a pair of outer plates 12 from both sides, and welding W the outer edges of the stacked outer plate 12a, intermediate plate 16, and outer plate 12b together to form a single unit. This eliminates the need to attach a brittle ceramic insulating layer block and fasten them with screws or the like, simplifies the manufacturing process, shortens manufacturing time, reduces costs, and is a manufacturing method suitable for mass production.

[0046] Furthermore, since the insulating coating 60 is formed by coating the entire surfaces of the outer plate / intermediate plate assembly 15 and the outer plate 12b with an insulating agent, the manufacturing process is simplified without the need for partial coating using masking tape, etc. Furthermore, if a fluorine-based insulating agent such as PFA, PTFE, or FEP is used as the insulating agent, the insulating coating 60 can be formed by applying an insulating paint or spraying insulating powder and heating it to, for example, 400°C.

[0047] To form the ceramic coating, it is preferable to use an aerosol deposition method, in which an aerosol containing ceramic particles dispersed in a gas is sprayed and collided at high speed against the insulating coating portions of the intermediate plate 16, the outer plate 12, or the soft X-ray shielding sheet 20. In this case, it is preferable to spray and collide the ceramic particles in a reduced-pressure environment in order to form a dense ceramic coating. Furthermore, the ceramic particles may be converted into plasma and sprayed to facilitate bonding of the colliding ceramic particles to each other to form a ceramic coating and to firmly bond them to the insulating coating portions. The ceramic particles may then be classified into particle sizes of, for example, 0.1-5 μm using a classification device.

[0048] In the above explanation, the intermediate plate 16 is stacked on one outer plate 12a to form the outer plate / intermediate plate assembly 15, and then coated with an insulating agent. However, the outer plate 12a and the intermediate plate 16 may also be coated separately and then stacked to form the outer plate / intermediate plate assembly 15.

[0049] Furthermore, the outer plate / intermediate plate assembly 15 or the outer plate 12a and intermediate plate 16, and the outer plate 12b do not have to be coated entirely. It is sufficient that the portions in contact with the soft X-ray shielding sheet 20 are covered with an insulating coating. When applying an insulating paint by dipping, it is easy to coat the entire surface. However, when spraying insulating powder, it is preferable to spray only one side of the outer plate / intermediate plate assembly 15 or the outer plate 12. This reduces the number of spraying times, simplifies the manufacturing process, and saves the amount of insulating powder to be sprayed. Furthermore, it is possible to prevent the insulating coating from being exposed to soft X-rays and generating dust. To prevent dust generation, dipping only one side may be used.

[0050] The insulating coating of the portion of the soft X-ray shielding sheet 20 that contacts the soft X-ray shielding sheet holder 10 can be produced as follows. First, the areas on both sides of the soft X-ray shielding sheet 20 where the flow paths 44 are open, i.e., the areas excluding the periphery, are masked with masking tape or a metal mask. Without masking, the insulating coating may block the openings of the flow paths 44 or narrow the cross-section of the flow paths 44. Furthermore, the insulating coating on the surface of the soft X-ray shielding sheet 20 may be exposed to soft X-rays, generating dust. After masking, an insulating coating is formed on the periphery or entire surface of the soft X-ray shielding sheet 20 using an insulating agent. When forming the insulating coating by spraying insulating agent powder and heating, care must be taken not to damage the masking tape, or a metal mask must be used, since the heat is used. After the insulating coating is formed, the masking tape or metal mask is removed, and the insulating coating is formed on the periphery of the soft X-ray shielding sheet 20.

[0051] The soft X-ray shielding sheet unit 1 is manufactured by overlapping the soft X-ray shielding sheet 20 having an insulating coating on the periphery with the middle plate 16 and outer plate 12 having no insulating coating as described above.

[0052] In the above description, the outer edges of the pair of outer plates 12 and the intermediate plate 16 are integrated by welding W. The welding W may be spot welding, seam welding, laser welding, or brazing, and is not particularly limited. However, spot welding is preferred because it inputs less heat to the outer plates 12 and the intermediate plate 16 and has less thermal impact on the insulating coating. When the insulating coating 60 is a ceramic coating, laser welding is also preferably used. Furthermore, instead of welding W, the integration may be achieved by other means such as screwing or crimping.

[0053] Furthermore, the soft X-ray shielding sheet 20, the pair of outer plates 12, and the intermediate plate 16 may be housed together in a case made of, for example, stainless steel, in which through-holes are formed at least in the portion through which the air 100 flows, or in which there is no wall, so as not to prevent the flow of the air 100 passing through the soft X-ray shielding sheet 20. When they are housed together in a case, the soft X-ray shielding sheet unit 1 can be installed in the container by simply welding the case to the container, which reduces the effect of heat on the insulating coating.

[0054] Furthermore, for example, if the outer plate / intermediate plate assembly 15 and the outer plate 12 are coated entirely with an insulating agent, the soft X-ray shielding sheet unit 1 can be housed and integrated into a case in which through holes are formed only in the areas corresponding to the through holes 14 of the outer plate 12, thereby preventing the insulating coating from being exposed to soft X-rays and the resulting generation of dust.

[0055] The main reference numerals used in this specification and the drawings are summarized below: 1 soft X-ray shielding sheet unit 10 soft X-ray shielding sheet holder 12 outer plate 14 through hole (of outer plate) 15 outer plate / intermediate plate assembly 16 intermediate plate 18 through hole (of intermediate plate) 20 soft X-ray shielding sheet 30 first outer layer sheet 31 inner surface of first outer layer sheet 32 ​​supply port 34 intermediate layer sheet 36 ionized air inlet opening 37 curved surface 38 ionized air passage 39 bent portion 40 second outer layer sheet 41 inner surface of second outer layer sheet 42 outlet port 44 flow path 60 insulating coating 92 soft X-ray 100 ionized air W welding

Claims

1. A soft X-ray shielding sheet unit comprising: a soft X-ray shielding sheet having a flow path formed therein through which air passes but soft X-rays do not; and a soft X-ray shielding sheet holder supporting the soft X-ray shielding sheet, the soft X-ray shielding sheet holder having: an intermediate plate having a through hole formed therein for accommodating the soft X-ray shielding sheet; and a pair of outer plates sandwiching the soft X-ray shielding sheet and the intermediate plate from both sides and having through holes formed therein through which the air passes; a soft X-ray shielding sheet unit comprising: a soft X-ray shielding sheet unit having a soft X-ray shielding sheet holder formed therein; and a soft X-ray shielding sheet unit having a soft X-ray shielding sheet holder and an insulating coating formed therein; 2. The soft X-ray shielding sheet unit according to claim 1, wherein a portion of the soft X-ray shielding sheet holder that contacts the soft X-ray shielding sheet is covered with an insulating coating.

3. The soft X-ray shielding sheet unit according to claim 1, wherein a portion of the soft X-ray shielding sheet that contacts the soft X-ray shielding sheet holder is covered with an insulating coating.

4. A soft X-ray shielding sheet unit according to any one of claims 1 to 3, wherein at least a portion of said outer plate protrudes into a portion corresponding to a through hole formed in said intermediate plate.

5. The soft X-ray shielding sheet unit according to claim 4, wherein the insulating coating is a fluorine-based coating.

6. The soft X-ray shielding sheet unit according to claim 4, wherein the insulating coating is a ceramic coating.

7. A method for manufacturing a soft X-ray shielding sheet unit as defined in claim 1 or 2, comprising the steps of: coating the intermediate plate with an insulating agent; coating the outer plates with an insulating agent; stacking the intermediate plate and one of the outer plates; arranging the soft X-ray shielding sheet in the through hole of the intermediate plate stacked on the outer plate; stacking the outer plate on the intermediate plate on which the soft X-ray shielding sheet is arranged, thereby sandwiching the soft X-ray shielding sheet and the intermediate plate; and integrating the stacked intermediate plate and the pair of outer plates.

8. A method for manufacturing a soft X-ray shielding sheet unit according to claim 7, further comprising the steps of: coating an outer plate / intermediate plate assembly, in which the intermediate plate and one of the outer plates are stacked together, with an insulating material; and coating the other one of the outer plates with an insulating material.

9. The method for manufacturing a soft X-ray shielding sheet unit according to claim 7, wherein the step of integrating comprises welding the overlapped intermediate plate and the pair of outer plates.

10. A method for manufacturing a soft X-ray shielding sheet unit as defined in claim 1 or 3, comprising the steps of: masking a surface of the soft X-ray shielding sheet where the flow paths are open; coating the masked soft X-ray shielding sheet with an insulating agent; removing the masking; stacking the intermediate plate and one of the outer plates; arranging the soft X-ray shielding sheet from which the masking has been removed in the through-hole of the intermediate plate stacked on the outer plate; stacking the outer plate on the intermediate plate on which the soft X-ray shielding sheet is placed, thereby sandwiching the soft X-ray shielding sheet and the intermediate plate; and integrating the stacked intermediate plate and the pair of outer plates.

11. The method for manufacturing a soft X-ray shielding sheet unit according to claim 10, wherein the step of integrating comprises welding the overlapped intermediate plate and the pair of outer plates.

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