Moisture-proof cover for heater

Abstract

This moisture-proof cover for a heater covers a heater that is exposed from a shaft of a stage. The moisture-proof cover for a heater comprises: a cylindrical body including a first opening end portion that is detachably fitted to the shaft, a second opening end portion on the opposite side from the first opening end portion, and a partition wall portion that separates the first opening end portion and the second opening end portion; a lid body that is fitted to the second opening end portion and closes off the second opening end portion; and a moisture-absorbing material stored in a space that is closed off by the lid body. The partition wall portion has a plurality of through-holes.

Description

Moisture-proof cover for heater

[0001] An embodiment of the present invention relates to a heater moisture-proof cover that prevents moisture absorption by a heater provided on a stage.

[0002] Semiconductor devices are found in almost all electronic devices and play an important role in their functionality. Semiconductor devices utilize the semiconducting properties of silicon and other materials. Semiconductor devices are constructed by stacking semiconductor, insulating, and conductive films on a substrate and then patterning these films. These films are deposited using methods such as evaporation, sputtering, chemical vapor deposition (CVD), or chemical reactions on the substrate, and then patterned using a photolithography process. The photolithography process involves forming a resist on the films to be patterned, exposing the resist, developing the resist to light, forming a resist mask by etching, partially removing the films, and finally removing the resist mask.

[0003] The film characteristics described above are significantly affected by the film deposition and etching conditions. One of these conditions is the temperature of the stage on which the substrate is placed. The stage is equipped with a heater, which can heat the substrate placed on the stage. Sheathed heaters are often used as stage heaters. Sheathed heaters have a structure in which, for example, a heating wire is inserted into a metal sheath, and an insulating material fills the gap between the metal sheath and the heating wire. The insulating material has high insulation resistance and can prevent electrical shorts between the metal sheath and the heating wire. However, the insulation resistance of insulating materials decreases when they absorb moisture. Therefore, when storing a stage with an exposed heater, the heater is usually covered with a moisture-proof cap containing a moisture-absorbing material to prevent moisture absorption by the heater (see, for example, Patent Document 1).

[0004] JP 2010-182437 A

[0005] However, in the moisture-proof cap described in Patent Document 1, once the cylindrical member and the opening of the bag-shaped member are sealed with adhesive, it is difficult to replace the moisture-absorbing material, and the moisture-proof cap cannot be reused. Also, since the size of the opening of the bag-shaped member changes when the size of the cylindrical member changes, it is necessary to produce a different moisture-proof cap for each stage.

[0006] An object of one embodiment of the present invention is to provide a moisture-proof cover for a heater that is highly versatile and allows easy replacement of the moisture-absorbing material.

[0007] A moisture-proof cover for a heater according to one embodiment of the present invention is a moisture-proof cover for a heater that covers a heater exposed from a shaft of a stage, and includes a cylindrical body including a first opening end that detachably fits with the shaft, a second opening end opposite the first opening end, and a partition portion that separates the first opening end from the second opening end, a lid body that fits with the second opening end and closes the second opening end, and a moisture-absorbing material contained within the space closed by the lid body, and the partition portion has a plurality of through holes.

[0008] A moisture-proof cover for a heater according to one embodiment of the present invention is a moisture-proof cover for a heater that covers a heater exposed from the shaft of a stage, and includes a cylindrical body including a first opening end that detachably fits with the shaft and a second opening end opposite the first opening end, a mesh member that is detachably installed inside the cylindrical body and separates the first opening end from the second opening end, a lid that mates with the second opening end and closes the second opening end, and a moisture-absorbing material contained within the space closed by the lid.

[0009] A moisture-proof cover for a heater according to one embodiment of the present invention is a moisture-proof cover for a heater that covers a heater exposed from a shaft of a stage, and includes a first cylindrical body including a first opening end that detachably fits with the shaft and a second opening end opposite the first opening end, a second cylindrical body including a third opening end that fits with the second opening end, a fourth opening end opposite the third opening end, and a partition portion that separates the third opening end from the fourth opening end, a lid body that fits with the fourth opening end and closes the fourth opening end, and a moisture-absorbing material contained in a space closed by the lid body, and the partition portion has a plurality of through holes.

[0010] A moisture-proof cover for a heater according to one embodiment of the present invention is a moisture-proof cover for a heater that covers a heater exposed from a shaft of a stage, and includes a first cylindrical body including a first opening end that detachably fits with the shaft and a second opening end opposite the first opening end, a second cylindrical body including a third opening end that detachably fits with the second opening end and a fourth opening end opposite the third opening end, a mesh member that is detachably installed inside one of the first cylindrical body and the second cylindrical body, a lid that detachably fits with the fourth opening end and closes the fourth opening end, and a moisture-absorbing material contained in the space closed by the lid.

[0011] The opening diameter of each of the plurality of through holes may be smaller than the particle size of the moisture absorbent material. The mesh member may have an opening size smaller than the particle size of the moisture absorbent material.

[0012] The lid may include an area through which the moisture absorbent material contained within the space can be seen.

[0013] The cover may include an exhaust port for discharging gas from the space and a valve installed at the exhaust port. The cover may further include a vacuum gauge.

[0014] The first open end may include threads that threadably mate with the shaft.

[0015] An O-ring groove into which an O-ring is fitted may be provided on the end face of the second open end.

[0016] An O-ring groove into which an O-ring is fitted may be provided on the end face of the fourth open end.

[0017] The cylindrical body or the first cylindrical body may further include a guide hole having a through hole through which the heater is inserted. An O-ring groove into which an O-ring is fitted may be provided on the inner wall of the through hole.

[0018] The mesh member may be disposed inside the first cylindrical body to separate the first open end from the second open end, and the mesh member may be disposed inside the second cylindrical body to separate the third open end from the fourth open end.

[0019] According to the heater moisture-proof cover of one embodiment of the present invention, the moisture-absorbing material can be easily replaced, thereby suppressing moisture absorption by the heater for a long period of time. Furthermore, the moisture-absorbing material removed from the heater moisture-proof cover can be directly reused. Furthermore, because the heater moisture-proof cover of one embodiment of the present invention is separated into a cylindrical body and a lid, it can be applied to different types of stages simply by changing the shape of the cylindrical body to match the shape of the stage shaft. In other words, because the lid and moisture-absorbing material of the heater moisture-proof cover are common to different types of stages, the heater moisture-proof cover has excellent versatility.

[0020] FIG. 1 is a schematic perspective view showing a usage mode of a moisture-proof cover for a heater according to one embodiment of the present invention. FIG. 2 is a schematic perspective view showing a usage mode of a moisture-proof cover for a heater according to one embodiment of the present invention. FIG. 3 is a schematic cross-sectional view showing the configuration of a moisture-proof cover for a heater according to one embodiment of the present invention. FIG. 4 is a schematic plan view showing the configuration of a cylindrical body of a moisture-proof cover for a heater according to one embodiment of the present invention. FIG. 5 is a schematic cross-sectional view showing the configuration of a moisture-proof cover for a heater according to one embodiment of the present invention. FIG. 6 is a schematic cross-sectional view showing the configuration of a moisture-proof cover for a heater according to one embodiment of the present invention. FIG. 7 is a schematic cross-sectional view showing the configuration of a moisture-proof cover for a heater according to one embodiment of the present invention.

[0021] Hereinafter, each embodiment of the invention disclosed in this application will be described with reference to the drawings. However, the present invention can be embodied in various forms without departing from the spirit of the invention, and should not be construed as being limited to the description of each embodiment described below.

[0022] In order to clarify the description, the drawings may show the width, thickness, shape, etc. of each part schematically compared to the actual embodiment, but these are merely examples and do not limit the interpretation of the present invention. Furthermore, in this specification and drawings, components having the same functions as those explained with reference to the previous drawings may be assigned the same reference numerals, and duplicate explanations may be omitted.

[0023] First Embodiment A heater moisture-proof cover 10 according to one embodiment of the present invention will be described with reference to FIGS. 1A to 3. FIG.

[0024] 1. Usage of the heater moisture-proof cover 10] A usage of the heater moisture-proof cover 10 will be described with reference to Figures 1A and 1B. Figures 1A and 1B are schematic perspective views showing a usage of the heater moisture-proof cover according to one embodiment of the present invention.

[0025] 1A , the stage 20 includes a plate 210 on which a substrate is placed, a shaft 220 connected to the plate 210, and a heater 230 disposed inside the plate 210 and the shaft 220 and exposed from the shaft 220. The heater 230 is electrically connected to wiring and the like of the film formation apparatus when the stage 20 is attached to the film formation apparatus. Therefore, the heater 230 extends outward from the open end of the shaft 220.

[0026] Until the stage 20 is attached to the film forming apparatus, the stage 20 is stored with the heater 230 exposed from the shaft 220. However, if the heater 230 contains a hygroscopic insulating material, a problem occurs in that the insulation resistance of the insulating material decreases due to moisture absorption. Therefore, to prevent the heater 230 from absorbing moisture, a heater moisture-proof cover 10 that fits onto the shaft 220 and covers the heater 230 is attached to the stage 20 (see FIG. 1B ).

[0027] 1A and 1B show a cylindrical body 110 and a lid body 120 as components that constitute the exterior of the heater moisture-proof cover 10, but the configuration of the heater moisture-proof cover 10 will be described in detail with reference to FIGS. 2 and 3. FIG. 2 is a schematic cross-sectional view showing the configuration of the heater moisture-proof cover 10 according to one embodiment of the present invention. FIG. 3 is a schematic plan view showing the configuration of the cylindrical body 110 of the heater moisture-proof cover 10 according to one embodiment of the present invention. For ease of explanation, the shaft 220 and heater 230, which are components of the stage 20, are shown by dotted lines in FIG. 2.

[0028] As shown in Figure 2, the heater moisture-proof cover 10 includes a cylindrical body 110, a lid 120, and a moisture-absorbing material 130. The cylindrical body 110 includes a first open end 110a, a second open end 110b opposite the first open end 110a, and a partition wall 110c separating the first open end 110a and the second open end 110b. The lid 120 includes an open end 120a and an internal cavity 120b. An upper surface 120c is provided on the opposite side of the open end 120a, and one end of the lid 120 is closed.

[0029] The cylindrical body 110 and the lid 120 are made of, for example, resin. The cylindrical body 110 and the lid 120 are manufactured by, for example, injection molding. When the cylindrical body 110 is manufactured by injection molding, the cylindrical body 110 can be manufactured with the first opening end 110a, the second opening end 110b, and the partition wall 110c integrally formed. However, the manufacturing method of the cylindrical body 110 is not limited to injection molding. The first opening end 110a, the second opening end 110b, and the partition wall 110c may be formed separately and then joined together to manufacture the cylindrical body 110.

[0030] The first open end 110a is detachably fitted to the shaft 220. For example, the first open end 110a and the shaft 220 are fitted together by inserting a portion of the shaft 220 along the inner wall of the first open end 110a. When the first open end 110a and the shaft 220 are fitted together, the heater 230 exposed from the shaft 220 is housed in a space surrounded by the first open end 110a and the partition wall 110c.

[0031] The second open end 110b is detachably fitted to the lid 120. A thread groove is provided on the inner peripheral surface of the second open end 110b. Furthermore, the outer peripheral surface of the open end 120a of the lid 120 has a threaded shape. Therefore, the cylindrical body 110 and the lid 120 are connected by threading the open end 120a of the lid 120 into the second open end 110b. In other words, the second open end 110b is closed by the lid 120. Furthermore, the lid 120 includes an internal cavity 120b, and the internal cavity 120b is also closed. An O-ring groove 110e is provided on the end face of the second open end 110b, and an O-ring 110f is attached thereto. When the cylindrical body 110 and the lid body 120 are connected, the O-ring 110f is pressed by the lid body 120, and the gap between the cylindrical body 110 and the lid body 120 is sealed.

[0032] An O-ring groove 110g may be provided on the end surface of the first open end 110a, and an O-ring 110h may be attached thereto. If the shaft 220 has a step, the step surface can be used to seal the heater moisture-proof cover 10 and the shaft 220. Specifically, the end surface of the first open end 110a of the heater moisture-proof cover 10 is abutted against the step surface of the shaft 220. This causes the O-ring 110h to be pressed by the step surface of the shaft 220, thereby providing a tighter seal between the first open end 110a of the heater moisture-proof cover 10 and the shaft 220. This embodiment may also be configured without the O-ring groove 110g and the O-ring 110h. Below, the components of the O-ring groove 110g and the O-ring 110h may be omitted.

[0033] 3 is a plan view showing the configuration of the cylindrical body 110 as viewed from the second open end 110b side, and the partition wall 110c includes a plurality of through holes 110d that communicate between the space on the first open end 110a side and the space on the second open end 110b side (including the internal cavity 120b of the lid 120). Note that, for convenience of explanation, when the cylindrical body 110 and the lid 120 are connected, the space on the first open end 110a side will be referred to as the "first space" and the space on the second open end 110b side will be referred to as the "second space."

[0034] The moisture absorbent 130 is accommodated in the space closed by the lid 120 and the partition wall 110c of the cylindrical body 110, i.e., the second space. For example, the moisture absorbent 130 is granular. When the moisture absorbent 130 is granular, the opening diameter of each of the plurality of through holes 110d is smaller than the particle diameter of the moisture absorbent 130. Therefore, the moisture absorbent 130 remains in the second space and does not move to the first space. Examples of the moisture absorbent 130 include silica gel, zeolite, CaO, BaO, MgSO ４ , Mg(ClO ４ ) ２ , MgO, P ２ O ５ , Al ２ O ３ , CaH ２ , NaH, LiAlH ４ , CaSO ４ , Na ２ SO ４ , CaCO ３ , K. ２ CO ３ , CaCl ２ , Ba(ClO ４ ) ２ One or more materials selected from the group consisting of Mg, Fe, and Ca can be used. Silica gel is particularly preferable as the moisture absorbent 130. Moisture-absorbing silica gel can be heated to evaporate the water and can be reused.

[0035] Depending on the material of the moisture absorbent material 130, it may be difficult to form it into a particulate form. For example, when the moisture absorbent material 130 is a powdered material or a deliquescent material, the moisture absorbent material 130 may be sealed in a bag-shaped member. In this case, the bag-shaped member containing the moisture absorbent material 130 is housed in the second space, and the size of the bag-shaped member is larger than the opening diameter of each of the plurality of through-holes 110d.

[0036] Depending on the material of the moisture absorbent 130, its color may change upon absorbing moisture. For example, if the moisture absorbent 130 is silica gel, the color of the silica gel changes from blue to pink upon absorbing moisture. When the moisture absorbent 130 has such properties, the lid 120 may be provided with an area (e.g., the top surface 120c) through which the moisture absorbent 130 can be seen. The color of the moisture absorbent 130 can be confirmed through the visible area, allowing the user to determine when the moisture absorbent 130 needs to be replaced. The visible area is preferably, but not limited to, translucent. Even if the color of the lid 120 is milky white, the color of the moisture absorbent 130 can be seen through the thinner portion by thinning a portion of the lid 120. Therefore, in this case, the color of the moisture absorbent 130 can be confirmed and the user can determine when the moisture absorbent 130 needs to be replaced.

[0037] The heater moisture-proof cover 10 is used in a configuration in which the cylindrical body 110 and the lid body 120 are connected (see FIGS. 1A and 1B). The moisture absorbent 130 in the second space can absorb moisture in the first space through the multiple through-holes 110d in the partition wall 110c. This can suppress moisture absorption by the heater 230 housed in the first space.

[0038] On the other hand, the heater moisture-proof cover 10 can be separated into the cylindrical body 110 and the lid body 120. By separating the cylindrical body 110 and the lid body 120, the moisture-absorbing material 130 can be removed, making it easy to replace the moisture-absorbing material 130. Furthermore, when storing the stage 20 to which the heater moisture-proof cover 10 is attached, the moisture-absorbing material 130 can be replaced by removing only the lid body 120 without removing the heater moisture-proof cover 10 itself from the stage 20. Therefore, by continuously replacing the moisture-absorbing material 130, it is possible to suppress moisture absorption by the heater for a long period of time. Furthermore, only the moisture-absorbing moisture-absorbing material 130 can be removed from the heater moisture-proof cover 10 and directly reused.

[0039] Furthermore, even if the shape of the shaft 220 of the stage 20 changes, it is only necessary to change the shape of only the cylindrical body 110, rather than changing the entire configuration of the heater moisture-proof cover 10. Specifically, it is only necessary to shape the first open end 110a of the cylindrical body 110 in accordance with the shape of the shaft 220 so that the cylindrical body 110 can fit onto the shaft 220. In this case, the lid body 120 and the moisture absorbent material 130 of the heater moisture-proof cover 10 are common to different types of stages 20, so the heater moisture-proof cover 10 has excellent versatility.

[0040] <First Modification of First Embodiment> A heater moisture-proof cover 10A, which is a modification of the heater moisture-proof cover 10, will be described with reference to Fig. 4. In the following, if the heater moisture-proof cover 10A includes the same components as the heater moisture-proof cover 10, the description of those components may be omitted.

[0041] 4 is a schematic cross-sectional view showing the configuration of a heater moisture-proof cover 10A according to one embodiment of the present invention. For ease of explanation, the shaft 220 and heater 230, which are components of the stage 20, are shown by dotted lines in FIG.

[0042] As shown in Fig. 4, the heater moisture-proof cover 10A includes a cylindrical body 110A, a lid body 120, and a moisture absorbent material 130. A thread groove 110i corresponding to the thread shape on the outer peripheral surface of the shaft 220 is provided on the inner peripheral surface of the first open end 110a of the cylindrical body 110A. If the outer peripheral surface of the shaft 220 has a thread shape, the heater moisture-proof cover 10A can be attached to the shaft 220 by utilizing the thread shape on the outer peripheral surface of the shaft 220. In other words, by threading the first open end 110a of the cylindrical body 110 onto the shaft 220, the heater moisture-proof cover 10A can be firmly fixed to the shaft 220.

[0043] In the heater moisture-proof cover 10A, the cylindrical body 110A and the lid 120 are also separable, allowing for easy replacement of the moisture-absorbent material 130. Furthermore, because the lid 120 and the moisture-absorbent material 130 of the heater moisture-proof cover 10A are common to different types of stages 20, the heater moisture-proof cover 10A is also highly versatile.

[0044] 5, a heater moisture-proof cover 10B, which is another modification of the heater moisture-proof cover 10, will be described. Note that, in the following, when the heater moisture-proof cover 10B includes the same components as the heater moisture-proof cover 10, the description of those components may be omitted.

[0045] Fig. 5 is a schematic cross-sectional view showing the configuration of a heater moisture-proof cover 10B according to one embodiment of the present invention. For ease of explanation, the shaft 220 and heater 230, which are components of the stage 20, are shown by dotted lines in Fig. 5.

[0046] As shown in FIG. 5 , the heater moisture-proof cover 10B includes a cylindrical body 110, a lid body 120B, and a moisture absorbent material 130. An exhaust port 120d and a vacuum gauge 120f are provided on the top surface 120c of the lid body 120B. The exhaust port 120d is connected to a vacuum pump (not shown) and can exhaust gas from the first and second spaces. That is, air can be exhausted through the exhaust port 120d to create a vacuum (a pressure lower than atmospheric pressure) in the first and second spaces. A valve 120e is attached to the exhaust port 120d, and closing the valve can maintain the vacuum in the first and second spaces. The vacuum gauge 120f can measure the pressure in the first and second spaces.

[0047] In the heater moisture-proof cover 10B, the first and second spaces can be evacuated, and the pressure in the first and second spaces can be checked using the vacuum gauge 120f. Therefore, the first and second spaces can be constantly evacuated, reducing the amount of moisture absorbed by the moisture absorbent 130. This can extend the replacement period for the moisture absorbent 130. In other words, the frequency with which the moisture absorbent 130 needs to be replaced can be reduced.

[0048] In the heater moisture-proof cover 10B, the cylindrical body 110 and the lid 120B are also separable, making it easy to replace the moisture-absorbent material 130. Furthermore, because the lid 120B and the moisture-absorbent material 130 of the heater moisture-proof cover 10B are common to different types of stages 20, the heater moisture-proof cover 10A is also highly versatile.

[0049] Second Embodiment A heater moisture-proof cover 11 according to one embodiment of the present invention will be described with reference to Fig. 6. In the following description, when the heater moisture-proof cover 11 includes the same components as the heater moisture-proof cover 10, the description of those components may be omitted.

[0050] Fig. 6 is a schematic cross-sectional view showing the configuration of a heater moisture-proof cover 11 according to one embodiment of the present invention. For ease of explanation, the shaft 220 and heater 230, which are components of the stage 20, are shown by dotted lines in Fig. 6.

[0051] As shown in FIG. 6 , the heater moisture-proof cover 11 includes a cylindrical body 111, a lid 121, a moisture absorbent 130, and a mesh member 140. The cylindrical body 111 includes a first open end 111a and a second open end 111b opposite the first open end 111a. The first open end 111a and the second open end 111b are connected to each other. The inner diameter of the first open end 111a is smaller than the inner diameter of the second open end 111b. Therefore, a step is formed at the boundary between the first open end 111a and the second open end 111b. An O-ring groove 111e is provided on the end face of the second open end 111b, and an O-ring 111f is attached thereto. The lid 121 includes an open end 121a and an internal cavity 121b. An upper surface portion 121c is provided on the opposite side of the open end portion 121a, and one end of the lid body 121 is closed.

[0052] The inner peripheral surface of the second open end 111b of the cylindrical body 111 is provided with a thread groove that corresponds to the thread shape of the outer peripheral surface of the open end 121a of the lid 121. Therefore, the open end 121a of the lid 121 is screwed onto the second open end 111b of the cylindrical body 111, thereby connecting the cylindrical body 111 and the lid 121.

[0053] The mesh member 140 is detachably installed on a step located between the first open end 111a and the second open end 111b. When the cylindrical body 111 and the lid 121 are connected, the mesh member 140 is sandwiched and fixed between the step in the cylindrical body 111 and the open end 121a of the lid 121. The mesh member 140 has a structure in which thin wires are woven into a mesh-like structure. The diameter of the thin wires is, for example, 0.5 mm or more and 1.5 mm or less, but is not limited thereto. If the diameter of the thin wires is too small, the strength of the mesh member 140 will be weak, and if the diameter of the thin wires is too large, the mesh openings will be large. The material of the mesh member 140 can be, but is not limited to, metal.

[0054] In the heater moisture-proof cover 11, a mesh member 140 separates a first space on the first open end 111a side of the cylindrical body 111 from a second space on the second open end 111b side of the cylindrical body 111. The second space includes the internal cavity 121b of the lid body 121. The moisture-absorbing material 130 is housed in the second space. When the moisture-absorbing material 130 is particulate, the mesh member 140 has a mesh size smaller than the particle size of the moisture-absorbing material 130. Therefore, the moisture-absorbing material 130 remains in the second space and does not move to the first space. The moisture-absorbing material 130 in the second space can absorb moisture in the first space through the mesh member 140. This suppresses moisture absorption by the heater 230 housed in the first space.

[0055] When the shape of the shaft 220 of the stage 20 is changed, it is only necessary to change the shape of the cylindrical body 111, rather than changing the entire configuration of the heater moisture-proof cover 11.

[0056] In the heater moisture-proof cover 11, the cylindrical body 111 and the lid 121 are separable, allowing for easy replacement of the moisture-absorbent material 130. Furthermore, since the lid 121 and the moisture-absorbent material 130 of the heater moisture-proof cover 11 are common to different types of stages 20, the heater moisture-proof cover 11 is highly versatile.

[0057] 7 and 8, a heater moisture-proof cover 11A, which is a modification of the heater moisture-proof cover 11, will be described. In the following, when the heater moisture-proof cover 11A includes the same components as the heater moisture-proof cover 11, the description of those components may be omitted.

[0058] Fig. 7 is a schematic cross-sectional view showing the configuration of a heater moisture-proof cover 11A according to one embodiment of the present invention. Fig. 8 is a schematic plan view showing the configuration of a cylindrical body 111A of the heater moisture-proof cover 11A according to one embodiment of the present invention. For ease of explanation, the shaft 220 and heater 230, which are components of the stage 20, are shown by dotted lines in Fig. 7.

[0059] As shown in FIG. 7 , the heater moisture-proof cover 11A includes a cylindrical body 111A, a lid 121, a moisture absorbent 130, and a mesh member 140. A flat heater guide 111h is provided within the first open end 111a of the cylindrical body 111A. FIG. 8 is a plan view showing the configuration of the cylindrical body 111A as viewed from the second open end 111b. The heater guide 111h includes a through-hole 111i through which the heater 230 is inserted. Specifically, when the shaft 220 is inserted into the first open end 111a, the heater 230 passes through the heater guide 111h while being guided by the through-hole 111i of the heater guide 111h. An O-ring groove 111j is provided on the inner wall of the through-hole 111i, and an O-ring 111k is fitted therein. The heater passing through the heater guide 111h is fixed in position by the O-ring 111k, so that even when the stage 20 to which the heater moisture-proof cover 11A is attached is transported, damage caused by collision of the heater 230 can be prevented.

[0060] When the cylindrical body 111A is manufactured by injection molding, the cylindrical body 111A can be manufactured in which the first open end 111a, the second open end 111b, and the heater guide 111h are integrally formed.

[0061] In the heater moisture-proof cover 11A as well, the cylindrical body 111A and the lid 121 are separable, making it possible to easily replace the moisture-absorbing material 130. Furthermore, since the lid 121 and the moisture-absorbing material 130 of the heater moisture-proof cover 11A are common to different types of stages 20, the heater moisture-proof cover 11A is also highly versatile.

[0062] Third Embodiment A heater moisture-proof cover 12 according to one embodiment of the present invention will be described with reference to Fig. 9. In the following description, when the heater moisture-proof cover 12 includes the same components as the heater moisture-proof cover 10, the description of those components may be omitted.

[0063] 9 is a schematic cross-sectional view showing the configuration of a heater moisture-proof cover 12 according to one embodiment of the present invention. For ease of explanation, the shaft 220 and heater 230, which are components of the stage 20, are shown by dotted lines in FIG.

[0064] As shown in FIG. 9 , the heater moisture-proof cover 12 includes a first cylindrical body 112-1, a second cylindrical body 112-2, a lid 122, and a moisture absorbent material 130. The first cylindrical body 112-1 includes a first open end 112a, a second open end 112b opposite the first open end 112a, and a partition wall 112c separating the first open end 112a and the second open end 112b. The partition wall 112c has a plurality of through holes 112d. An O-ring groove 112e is provided in the end face of the second open end 112b, and an O-ring 112f is fitted in the groove. The second cylindrical body 112-2 includes a third open end 112l and a fourth open end 112m. An O-ring groove 112n is provided in the end face of the fourth open end 112m, and an O-ring 112o is fitted in the groove. The lid 122 includes an open end 122a and an internal cavity 122b. An upper surface 122c is provided on the opposite side of the open end 122a, and one end of the lid 122 is closed.

[0065] The inner peripheral surface of the second open end 112b of the first cylindrical body 112-1 is provided with a thread groove that corresponds to the thread shape on the outer peripheral surface of the third open end 112l of the second cylindrical body 112-2. Therefore, the first cylindrical body 112-1 and the second cylindrical body 112-2 are connected by threading the third open end 112l of the second cylindrical body 112-2 into the second open end 112b of the first cylindrical body 112-1. In addition, the inner peripheral surface of the fourth open end 112m of the second cylindrical body 112-2 is provided with a thread groove that corresponds to the thread shape on the outer peripheral surface of the open end 122a of the lid 122. Therefore, the second cylindrical body 112-2 and the lid body 122 are connected by screwing the open end 122a of the lid body 122 into the fourth open end 112m of the second cylindrical body 112-2.

[0066] In the heater moisture-proof cover 12, a partition wall 112c separates a first space on the first open end 112a side of the first cylindrical body 112-1 from a second space on the second open end 112b side of the first cylindrical body 112-1. The second space includes an internal cavity 122b of the cover body 122. The moisture-absorbing material 130 is housed in the second space. When the moisture-absorbing material 130 is a particle, the opening diameter of each of the multiple through-holes 112d in the partition wall 112c is smaller than the particle diameter of the moisture-absorbing material 130. Therefore, the moisture-absorbing material 130 remains in the second space and does not move to the first space. The moisture-absorbing material 130 in the second space can absorb moisture in the first space through the multiple through-holes 112d. This suppresses moisture absorption by the heater 230 housed in the first space.

[0067] In the heater moisture-proof cover 12, the second cylindrical body 112-2 can function as a joint member. That is, it is possible to install multiple second cylindrical bodies 112-2 between the first cylindrical body 112-1 and the lid body 122. By using multiple second cylindrical bodies 112-2, the volume of the second space can be increased, and more moisture absorbent material 130 can be accommodated in the second space. This makes it possible to extend the replacement interval of the moisture absorbent material 130. In other words, it is possible to reduce the frequency of replacement of the moisture absorbent material 130.

[0068] When the shape of the shaft 220 of the stage 20 is changed, it is only necessary to change the shape of the first cylindrical body 112-1, rather than changing the configuration of the entire heater moisture-proof cover 12.

[0069] In the heater moisture-proof cover 12, the first cylindrical body 112-1, the second cylindrical body 112-2, and the lid body 122 are separable, allowing for easy replacement of the moisture-absorbent material 130. Furthermore, because the lid body 122 and the moisture-absorbent material 130 of the heater moisture-proof cover 12 are common to different types of stages 20, the heater moisture-proof cover 12 has excellent versatility.

[0070] Fourth Embodiment A heater moisture-proof cover 13 according to one embodiment of the present invention will be described with reference to Fig. 10. In the following description, when the heater moisture-proof cover 13 includes the same components as the heater moisture-proof cover 11, the description of those components may be omitted.

[0071] Fig. 10 is a schematic cross-sectional view showing the configuration of a heater moisture-proof cover 13 according to one embodiment of the present invention. For ease of explanation, the shaft 220 and heater 230, which are components of the stage 20, are shown by dotted lines in Fig. 10.

[0072] As shown in FIG. 10 , the heater moisture-proof cover 13 includes a first cylindrical body 113-1, a second cylindrical body 113-2, a lid 123, a moisture absorbent 130, and a mesh member 140. The first cylindrical body 113-1 includes a first open end 113a and a second open end 113b opposite the first open end 113a. The first open end 113a and the second open end 113b are connected to each other. The inner diameter of the first open end 113a is smaller than the inner diameter of the second open end 113b. Therefore, a step is formed at the boundary between the first open end 113a and the second open end 113b. An O-ring groove 113e is provided on the end face of the second open end 113b, and an O-ring 113f is attached thereto. The second cylindrical body 113-2 includes a third open end 113l and a fourth open end 113m. An O-ring groove 113n is provided on the end face of the fourth open end 113m, and an O-ring 113o is fitted in the groove. The lid 123 includes an open end 123a and an internal cavity 123b. An upper surface 123c is provided on the opposite side of the open end 123a, and one end of the lid 123 is closed.

[0073] The inner peripheral surface of the second open end 113b of the first cylindrical body 113-1 is provided with a thread groove that corresponds to the thread shape on the outer peripheral surface of the third open end 113l of the second cylindrical body 113-2. Therefore, the first cylindrical body 113-1 and the second cylindrical body 113-2 are connected by threading the third open end 113l of the second cylindrical body 113-2 with the second open end 113b of the first cylindrical body 113-1. In addition, the inner peripheral surface of the fourth open end 113m of the second cylindrical body 113-2 is provided with a thread groove that corresponds to the thread shape on the outer peripheral surface of the open end 123a of the lid 123. Therefore, the second cylindrical body 113-2 and the lid body 123 are connected by screwing the open end 123a of the lid body 123 into the fourth open end 113m of the second cylindrical body 113-2.

[0074] In the heater moisture-proof cover 13, a mesh member 140 separates a first space on the first open end 113a side of the first cylindrical body 113-1 from a second space on the second open end 113b side of the first cylindrical body 113-1. The second space includes the internal cavity 123b of the cover body 123. The moisture-absorbent material 130 is housed in the second space. When the moisture-absorbent material 130 is particulate, the mesh member 140 has a mesh size smaller than the particle size of the moisture-absorbent material 130. Therefore, the moisture-absorbent material 130 remains in the second space and does not move to the first space. The moisture-absorbent material 130 in the second space can absorb moisture in the first space through the mesh member 140. This suppresses moisture absorption by the heater 230 housed in the first space.

[0075] In the heater moisture-proof cover 13, the second cylindrical body 113-2 can function as a joint member. That is, it is possible to install multiple second cylindrical bodies 113-2 between the first cylindrical body 113-1 and the lid body 123. By using multiple second cylindrical bodies 113-2, the volume of the second space can be increased, and more moisture absorbent material 130 can be accommodated in the second space. This makes it possible to extend the replacement interval of the moisture absorbent material 130. In other words, it is possible to reduce the frequency of replacement of the moisture absorbent material 130.

[0076] Although the above describes a configuration in which the mesh member 140 is installed on a step inside the first cylindrical body 113-1, in this embodiment, it is also possible to install the mesh member 140 on a step inside the second cylindrical body 113-2. In the heater moisture-proof cover 13, the position at which the mesh member 140 is installed can be changed depending on the length of the heater 230 exposed from the shaft 220.

[0077] The above-described embodiments of the present invention may be combined as appropriate as long as they are not mutually inconsistent. Furthermore, even if a person skilled in the art appropriately adds or deletes components or modifies the design based on each embodiment, the addition, deletion, or modification of components is included in the scope of the present invention as long as the gist of the present invention is maintained.

[0078] Furthermore, even if there are other effects and advantages different from those brought about by the above-mentioned embodiments, those that are clear from the description in this specification or that can be easily predicted by a person skilled in the art are naturally understood to be brought about by the present invention.

[0079] 10, 10A, 10B, 11, 11A, 12, 13: heater moisture-proof cover, 110, 110A, 111, 111A: cylindrical body, 112-1, 113-1: first cylindrical body, 112-2, 113-2: second cylindrical body, 110a, 111a, 112a, 113a: first opening end, 110b, 111b, 112b, 113b: second opening end, 110c, 112c: partition wall portion, 110d, 112d: through hole, 110e, 111e, 112e, 113e: O-ring groove, 110f, 111f, 112f, 113f: O-ring, 110g: O-ring groove, 110h: O-ring, 110i: screw groove, 111h: heater guide, 111i: through hole, 111j: O-ring groove, 111k: O-ring, 112l, 113l: third opening end, 112m, 113m: fourth opening end, 112n, 113n: O-ring groove, 112o, 113o: O-ring, 120, 120B, 121, 122, 123: lid, 120a, 121a, 122a, 123a: opening end, 120b, 121b, 122b, 123b: internal cavity, 120c, 121c, 122c, 123c: upper surface, 120d: exhaust port, 120e: valve, 120f: vacuum gauge, 130: moisture absorbent material, 140: Mesh member, 20: Stage, 210: Plate, 220: Shaft, 230: Heater

Claims

1. A moisture-proof cover for a heater which covers a heater exposed from a shaft of a stage, comprising: a cylindrical body including a first opening end which detachably fits with the shaft, a second opening end opposite the first opening end, and a partition portion separating the first opening end and the second opening end; a lid which fits with the second opening end and closes the second opening end; and a moisture-absorbing material contained within the space closed by the lid, wherein the partition portion has a plurality of through holes.

2. A moisture-proof cover for a heater which covers a heater exposed from a shaft of a stage, comprising: a cylindrical body including a first opening end which detachably fits with the shaft and a second opening end opposite the first opening end; a mesh member which is detachably installed inside the cylindrical body and separates the first opening end from the second opening end; a lid which mates with the second opening end and closes the second opening end; and a moisture-proof material contained in the space closed by the lid.

3. A moisture-proof cover for a heater which covers a heater exposed from a shaft of a stage, comprising: a first cylindrical body including a first opening end which detachably fits with the shaft and a second opening end opposite the first opening end; a second cylindrical body including a third opening end which fits with the second opening end, a fourth opening end opposite the third opening end, and a partition portion which separates the third opening end and the fourth opening end; a lid which fits with the fourth opening end and closes the fourth opening end; and a moisture-proof material contained in a space closed by the lid, wherein the partition portion has a plurality of through holes.

4. A moisture-proof cover for a heater that covers a heater exposed from a shaft of a stage, comprising: a first cylindrical body including a first opening end that detachably fits with the shaft and a second opening end opposite the first opening end; a second cylindrical body including a third opening end that fits with the second opening end and a fourth opening end opposite the third opening end; a mesh member installed inside one of the first cylindrical body and the second cylindrical body; a lid that fits with the fourth opening end and closes the fourth opening end; and a moisture-proof material contained in a space closed by the lid.

5. A moisture-proof cover for a heater as described in claim 1 or 3, wherein the opening diameter of each of the plurality of through holes is smaller than the particle diameter of the moisture absorbent material.

6. A moisture-proof cover for a heater as described in claim 2 or 4, wherein the mesh size of the mesh member is smaller than the particle size of the moisture-absorbent material.

7. A moisture-proof cover for a heater as described in any one of claims 1 to 4, wherein the lid body includes an area in which the moisture-absorbing material contained in the space can be visually observed.

8. A moisture-proof cover for a heater as described in any one of claims 1 to 4, wherein the lid body includes an exhaust port for discharging gas within the space, and a valve installed at the exhaust port.

9. The moisture-proof cover for a heater according to claim 8, wherein the lid further includes a vacuum gauge.

10. A moisture-proof cover for a heater as described in any one of claims 1 to 4, wherein the first open end includes a threaded groove that screws into the shaft.

11. A moisture-proof cover for a heater as claimed in any one of claims 1 to 4, wherein an O-ring groove for receiving an O-ring is provided on the end face of the second opening end.

12. A moisture-proof cover for a heater as claimed in claim 3 or 4, wherein an O-ring groove for receiving an O-ring is provided on the end face of said fourth opening end.

13. The moisture-proof cover for a heater according to claim 2, wherein the cylindrical body further includes a heater guide having a through hole through which the heater is inserted.

14. The moisture-proof cover for a heater according to claim 13, wherein an O-ring groove for receiving an O-ring is provided on the inner wall of the through hole.

15. A moisture-proof cover for a heater as described in claim 3 or 4, wherein the first cylindrical body further includes a heater guide having a through hole through which the heater is inserted.

16. The moisture-proof cover for a heater according to claim 15, wherein an O-ring groove for receiving an O-ring is provided on the inner wall of the through hole.

17. The moisture-proof cover for a heater as described in claim 4, wherein the mesh member is disposed inside the first cylindrical body so as to separate the first open end and the second open end.

18. A moisture-proof cover for a heater as described in claim 4, wherein the mesh member is disposed inside the second cylindrical body so as to separate the third open end and the fourth open end.

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