Substrate housing container and manufacturing method of the same

Abstract

To provide a substrate housing container capable of preventing and removing a position deviation and a falling of a packing, a damage of a substrate, and an increase of dust, and provide a manufacturing method of the same.SOLUTION: In a substrate housing container nipping an endless packing 20 between an opening top part 2 of an outer box 1 for housing a semiconductor wafer and a top cover, an attachment groove 4 for the packing 20 is formed to a peripheral edge part 3 of the top part 2, a tightened hole 5 for the packing 20 is bored into the attachment groove 4, and the tightened hole 5 is divided into a narrower part 6 that is contacted to the attachment groove 4, a narrower part 7 of which a width is expanded so as to be contacted to the narrower part 6, and a width narrowest part 8 of which the width is narrowed so as to be contacted to the narrower part 7. The packing 20 is formed by: a base part 21 that is fitted to the attachment groove 4; a narrow part 22 that is tightly fitted to the narrower part 6 so as to be contacted to the base part 21; a width wide part 23 that is tightly fitted to the narrower part 7 so as to be contacted to the narrow part 22; and a narrowest width part 24 that is tightly fitted to the width narrowest part 8 so as to be contacted to the width wide part 23.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a substrate storage container for storing substrates such as semiconductor wafers, and a method for manufacturing the same. [Background technology]

[0002] As shown in Figures 8 to 10, a conventional substrate storage container comprises an outer box 1 capable of storing a plurality of semiconductor wafers, a top lid 10 that fits over an open upper portion 2 of the outer box 1, and an endless gasket 30 that is sandwiched between the outer box 1 and the top lid 10, and is used for storing, transferring, and transporting a plurality of semiconductor wafers (see Patent Document 1).

[0003] As shown in Figures 8 to 10, the outer box 1 is molded from a resin-containing molding material into a cylindrical, bottomed, open-top box, and contains a cassette that stores multiple aligned semiconductor wafers. This outer box 1 has an endless, frame-shaped mounting groove 4 for a packing 30 recessed into the peripheral portion 3 of the open top 2, and multiple locking projections 9 for a top lid 10 are formed on the upper part of the outer surface of each of the two side walls.

[0004] As shown in Figure 8, the top cover 10 is molded into a low, roughly box-like shape from a resin-containing molding material, and a long, bendable locking piece 11 is formed at the bottom of each of the two side walls to fit into and lock onto the locking protrusion 9 of the outer box 1.

[0005] 9 and 10, the packing 30 is formed into an elastically deformable frame shape from a molding material containing resin, and is loosely fitted with a gap in the mounting groove 4 of the outer box 1. For example, the packing 30 is formed into a cross section of a roughly H-shape, with its bifurcated lower part 31 contacting the bottom surface of the mounting groove 4, a plate piece 32 extending horizontally inward from near the center to position and contact the inner wall surface of the mounting groove 4, and an upright upper part 33 being pressed against the peripheral part of the open lower part of the top cover 10 and deforming. After being molded, such a packing 30 is loosely fitted with a gap in the mounting groove 4 of the outer box 1, and deforms between the upper part 2 of the outer box 1 and the top cover 10 to provide a sealing effect, preventing the stored semiconductor wafers from being contaminated by particles from the outside. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Utility Model Application Publication No. 2-106831 Summary of the Invention [Problem to be solved by the invention]

[0007] Conventional substrate storage containers are constructed as described above, and are assembled by simply loosely fitting a separate part, gasket 30, into the mounting groove 4 of the outer box 1 with a clearance. This causes problems such as the gasket 30 rattling and shifting out of position, which can result in the gasket 30 being easily dislodged from the mounting groove 4 of the outer box 1, the gasket 30 being dislodged from the mounting groove 4 of the outer box 1 and causing damage to the semiconductor wafers, or the sealing performance of the gasket 30 being reduced, resulting in an increase in particles from outside.

[0008] The present invention has been made in consideration of the above, and aims to provide a substrate storage container and a manufacturing method thereof that can reduce the gap between the outer box and the gasket, thereby preventing or wiping away the risk of the gasket shifting or falling off, damage to the substrate, and the increase of dust. [Means for solving the problem]

[0009] In order to solve the above problems, the present invention provides a method for inserting a packing between an opening of an outer box capable of storing a substrate and a lid, the method comprising the steps of: A mounting groove for a packing is formed in the peripheral portion of the opening of the outer box, and a seal hole for the packing is formed in the mounting groove, and the seal hole is divided into a narrow portion connected to the mounting groove, a wide portion connected to the narrow portion and having a wider width, and a narrowest portion connected to the wide portion and having a narrower width, The packing is characterized by comprising a base portion attached to the mounting groove of the outer box, a narrow portion connected to the base and in close contact with the narrow portion of the sealed hole of the outer box, a wide portion connected to the narrow portion and in close contact with the wide portion of the sealed hole, and a narrowest portion connected to the wide portion and in close contact with the narrowest portion of the sealed hole.

[0010] The outer box may be a top-open box having an opening at the top. Also, the outer box can be molded from a molding material containing a thermoplastic resin, and the packing can be molded from a molding material containing a thermosetting resin having excellent elasticity. Furthermore, the cross sections of the narrow portion, wide portion and narrowest portion of the packing can be made substantially polygonal, and the narrowest portion can be formed sharply so as to face inward of the packing.

[0011] In order to solve the above problems, the present invention provides a method for manufacturing a substrate storage container according to claim 1 or 2, comprising the steps of: The method is characterized in that a packing is molded from a molding material containing an elastic thermosetting resin, this packing is inserted into a metal mold for molding the outer box and the mold is clamped, the metal mold is filled with a molding material containing a thermoplastic resin, and then the molding material is cooled and solidified to form the outer box.

[0012] Here, the substrate in the claims includes semiconductor wafers with diameters of at least φ125 mm, 150 mm, 200 mm, and 300 mm, rectangular quartz glass photomask materials, liquid crystal substrates, and the like. The outer box and the lid can be formed transparent, opaque, or translucent as necessary. The sealed hole of the outer box can be formed to have a cross section that is approximately polygonal, approximately elliptical, approximately track-shaped, approximately arrowhead-shaped, or the like. The narrow part, wide part, and narrowest part of the packing can also be formed to have a cross section that is approximately polygonal, approximately elliptical, approximately track-shaped, approximately arrowhead-shaped, or the like.

[0013] According to the present invention, the narrow, wide and narrowest portions of the packing are fitted into the sealed holes of the opening of the outer box with almost no gaps, thereby preventing the packing from rattling and becoming displaced. Effect of the Invention

[0014] According to the present invention, the gap between the outer box and the gasket can be reduced, thereby preventing or eliminating the risk of the gasket becoming misaligned or falling off, damage to the circuit board, and the increase of dust.

[0015] According to the invention described in claim 2, when the packing is inserted into a mold for molding the outer box and the outer box is subsequently molded, the packing is molded from a thermosetting resin, so that it is possible to prevent the thermoplastic resin of the molding material forming the outer box from welding to the packing.

[0016] According to the invention described in claim 3, when the packing has a cross section of a substantially polygonal shape, particularly when the narrow, wide and narrowest parts of the packing have a cross section of a substantially pentagonal or deformed substantially rhombus, it is possible to suppress the flow of the thermoplastic resin forming the outer box from being hindered. In addition, since the narrowest part of the packing faces inward of the packing, i.e., in the direction in which the thermoplastic resin forming the outer box flows, the narrowest part is less affected by the resin pressure of the thermoplastic resin forming the outer box and is less likely to move. Therefore, the sealed hole of the outer box can be formed in the same shape near the packing with almost no gaps.

[0017] According to the invention described in claim 4, the packing is molded in advance and inserted into the mold for molding the outer box, and the outer box with the packing is molded, so that it is possible to continuously form a narrow part and a wide part having different widths in the sealing hole of the outer box. Furthermore, in consideration of the undercut of the sealing hole of the outer box, it is possible to save the trouble of dividing the mold for molding the outer box and providing a special mechanism such as a slide mechanism, and to simplify the configuration of the mold. [Brief description of the drawings]

[0018] [Figure 1] 1 is a cross-sectional perspective view partially showing an outer box in an embodiment of a substrate storage container and a manufacturing method thereof according to the present invention. [Diagram 2]1 is a cross-sectional perspective view partially showing an upper peripheral portion of an outer box and a packing in an embodiment of a substrate storage container and a manufacturing method thereof according to the present invention. FIG. [Diagram 3] 1 is a cross-sectional explanatory view partially showing an upper peripheral portion of an outer box and a packing in an embodiment of a substrate storage container and a manufacturing method thereof according to the present invention. FIG. [Figure 4] 10 is a cross-sectional explanatory view showing a state in which a packing used during manufacture is pulled out from an upper peripheral portion of an outer box in an embodiment of a substrate storage container according to the present invention. FIG. [Diagram 5] 13 is an explanatory cross-sectional view showing a state in which a new, unused gasket is inserted into the upper peripheral portion of the outer box in an embodiment of a substrate storage container according to the present invention. FIG. [Figure 6] 11 is a cross-sectional perspective view showing a state in which a new, unused gasket is fitted and inserted into the upper peripheral portion of the outer box in an embodiment of a substrate storage container according to the present invention. FIG. [Figure 7] 11 is a cross-sectional perspective view showing the relationship between an upper peripheral portion of an outer box and a new packing in an embodiment of a substrate storage container according to the present invention. FIG. [Figure 8] FIG. 2 is a perspective view showing a substrate storage container; [Figure 9] 9 is a cross-sectional perspective view partially showing an outer box of the substrate storage container of FIG. 8. [Figure 10] 10 is a cross-sectional perspective view partially showing the mounting groove and packing of the outer box of FIG. 9. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] A preferred embodiment of the present invention will be described below with reference to the drawings. As shown in FIGS. 1 to 8, the substrate storage container in this embodiment is a storage container that includes an outer box 1 for storing semiconductor wafers, which are substrates, a cassette stored in the outer box 1, a top lid 10 that fits and covers the open upper part 2 of the outer box 1 in a freely detachable manner, a retainer that holds the upper peripheral part of the semiconductor wafers stored in the cassette, and an endless gasket 20 that is sandwiched between the outer box 1 and the top lid 10. When molding the outer box 1 using a mold for molding the outer box, the gasket 20 that has been molded in advance is inserted, and the outer box 1 with the gasket 20 is insert-molded, thereby contributing to the achievement of Goal 9 of the SDGs (the United Nations' international goals for sustainable development, consisting of 17 global goals and 169 targets (achievement criteria)) adopted at the United Nations Summit.

[0020] 1 to 3, 6 and 7, the outer box 1 is injection molded from a molding material containing thermoplastic resin into a bottomed, rectangular cylindrical top open box with an open upper portion 2, and detachably stores a rectangular cylindrical cassette storing a plurality of aligned semiconductor wafers (e.g., silicon wafers with a diameter of 200 mm, etc.) The thermoplastic resin used as the molding material for forming the outer box 1 is not particularly limited, but examples thereof include polypropylene resin, polycarbonate resin, polyetherimide resin, polyetheretherketone resin, polybutylene terephthalate resin, etc.

[0021] The molding material may be only the above-mentioned thermoplastic resin, but conductive substances such as carbon fibers, carbon nanotubes, and conductive polymers, various antistatic agents such as anionic, cationic, and nonionic antistatic agents, glass fibers or carbon fibers for improving rigidity, ultraviolet absorbers, and the like may be added as necessary.

[0022] The outer box 1 has an endless frame-shaped mounting groove 4 for a packing 20 formed in a peripheral portion 3 of an open upper portion 2, and a sealing hole 5 for the packing 20 is drilled in the mounting groove 4, and a plurality of locking projections 9 for a top cover 10 are formed in a line on the upper portion of the outer surface of each of the two side walls. As shown in Figs. 2 and 3, the sealing hole 5 of the outer box 1 is formed in a polygonal cross section (pentagon, modified rhombus, etc.) or arrowhead shape, and includes a narrow portion 6 connected to the center of the bottom surface of the mounting groove 4, a wide portion 7 connected to the narrow portion 6 and increasing in width as it moves downward, and a narrowest portion 8 connected to the wide portion 7 and decreasing in width as it moves downward. The narrowest portion 8 is formed sharply in a lead-in shape and is oriented inwardly of the outer box 1 at an angle.

[0023] As shown in Fig. 8, the top cover 10 is injection molded from a molding material containing thermoplastic resin into a generally box-like shape with a low back, and horizontally long locking pieces 11 that fit and lock onto the locking projections 9 of the outer box 1 are integrally formed in a bendable manner at the lower part of both side walls, and each locking piece 11 is formed in a striped pattern. The thermoplastic resin used as the molding material for forming the top cover 10 is not particularly limited, but examples thereof include polycarbonate resin and polypropylene resin. As with the outer box 1, conductive materials, antistatic agents, glass fibers, carbon fibers, ultraviolet absorbing agents, and the like are selectively added to the molding material. A retainer for holding the semiconductor wafer by elastically holding the upper peripheral edge of the semiconductor wafer with a plurality of bending holding members is detachably attached to the inner ceiling of the top cover 10.

[0024] As shown in Figures 1 to 3, the packing 20 is formed into an elastically deformable frame shape using a molding material containing a thermosetting resin, and is detachably fitted into the mounting groove 4 and the sealed hole 5 of the outer box 1. The reason why a thermosetting resin is used as the molding material for molding this packing 20 is that if a thermoplastic resin is used, it will be compatible with the molding material of the outer box 1 during molding of the outer box 1, making it impossible to remove the packing 20 later. The thermosetting resin used as the molding material for molding the packing 20 is not particularly limited, but an elastomer that allows the packing 20 to be removed or replaced, specifically urethane rubber or fluororubber, which has excellent heat resistance and elasticity, is used. In addition to the thermosetting resin, various fillers are selectively added to the molding material.

[0025] The packing 20 comprises a base 21 having a plate-shaped cross section which fits into the mounting groove 4 of the outer box 1, a narrow portion 22 connected to the underside of the base 21 and fitted into and in close contact with the narrow portion 6 of the sealed hole 5 of the outer box 1, a wide portion 23 connected to the narrow portion 22 and fitted into and in close contact with the wide portion 7 of the sealed hole 5, and a narrowest portion 24 connected to the wide portion 23 and fitted into and in close contact with the narrowest portion 8 of the sealed hole 5, and in order to prevent the occurrence of gaps, the narrow portion 22, the wide portion 23, and the narrowest portion 24 are formed into a polygonal cross section (pentagon, deformed rhombus, etc.) similar to the sealed hole 5 of the outer box 1, or an arrowhead shape, and function to prevent rattling, displacement, and falling off from the sealed hole 5.

[0026] As shown in FIG. 2, narrow portion 22, wide portion 23, and narrowest portion 24 of packing 20 are formed so that narrowest portion 24 is sharply formed in a lead-in shape, and at least narrowest portion 24 is oriented at an angle toward the inside of packing 20, in other words, in the direction in which the thermoplastic resin that forms outer box 1 flows during molding (see the arrow in FIG. 2).

[0027] The hardness of the packing 20, when measured with a type A durometer, is preferably A70° to A90°, more preferably A80° to A90°, and even more preferably A85° to A90°. This is because if the hardness of the packing 20 is in the range of A70° to A90°, the packing 20 can be easily removed and replaced.

[0028] In the above configuration, when manufacturing the outer box 1 of the substrate storage container, first, a molding material containing a thermosetting resin having excellent heat resistance and elasticity is prepared, and this molding material is filled into a high-temperature mold for molding a gasket that has been clamped, and this molding material is cooled and solidified to form the gasket 20, and then the mold is opened to demold the gasket 20.

[0029] Next, once the packing 20 has been molded, this packing 20 is inserted into a metal mold for molding the outer box and the mold is clamped. The reason why the packing 20 is injection molded in advance and inserted into the metal mold for molding the outer box is that if the outer box 1 is molded by a normal injection molding method without using the packing 20, the recessed portion (between the multiple dotted lines in FIG. 3) between the narrow portion 6 and the wide portion 7 of the sealed hole 5 of the outer box 1 will be undercut, and unless the metal mold for molding the outer box is divided and a special mechanism such as a slide mechanism is installed, it will be extremely difficult to mold and demold the outer box 1.

[0030] Once the metal mold for molding the outer box is closed, molten molding material containing a thermoplastic resin is injected into the metal mold to fill it, and the molten molding material is then post-filled and the molding material is cooled and solidified to form outer box 1 having mounting groove 4 and sealed hole 5. After that, the metal mold is opened and outer box 1 is demolded, thereby manufacturing outer box 1 having gasket 20 at open upper part 2.

[0031] In this case, since the packing 20 is molded from a thermosetting resin, not a thermoplastic resin, welding of the thermoplastic resin of the molding material forming the outer box 1 is prevented, and the packing 20 can be removed and replaced later. Also, since the narrowest part 24 of the packing 20 is oriented at an angle in the flow direction of the thermoplastic resin that molds the outer box 1, resistance is reduced and the narrowest part 24 is not affected by the resin pressure of the thermoplastic resin that molds the outer box 1 and does not wobble. Therefore, the mounting groove 4 and the sealed hole 5 can be appropriately formed around the packing 20 later using it as a mold.

[0032] If the packing 20 used during manufacture deteriorates or becomes damaged after a long period of use of the substrate storage container, the packing 20 used during manufacture can be grasped and pulled out from the upper portion 2 of the outer box 1 (see FIG. 4), and because the packing 20 has excellent elasticity, it can be easily pulled out and removed. After the packing 20 used during manufacture has been pulled out and removed, an unused packing 20A can be tightly fitted into the sealed hole 5 of the outer box 1 so that there are no gaps (see FIGS. 5 to 7).

[0033] The unused new packing 20A at this time is unrelated to the molding of the outer box 1, and may be molded from a molding material containing elastic thermosetting resin or may be molded from a molding material containing elastic thermoplastic resin. Also, if the narrow width portion 22, the wide width portion 23, and the narrowest width portion 24 of the packing 20A are the same shape, the base 21A of the packing 20A may be polygonal, or a deformable standing piece 25 may be formed by extending upward from the base 21A, and the standing piece 25 may be pressed against the peripheral portion of the lower opening of the top lid 10.

[0034] According to the above, the narrow portion 22, the wide portion 23, and the narrowest portion 24 of the packing 20 are tightly fitted into the sealed hole 5 of the outer box 1 without any gaps, and the narrow portion 22 and the wide portion 23 have a catch function, which prevents the packing 20 from rattling and shifting out of position. This eliminates the risk that the packing 20 will easily come off the mounting groove 4 of the outer box 1, that the packing 20 will come off the mounting groove 4 of the outer box 1 and cause damage to the semiconductor wafer, or that the sealing performance of the packing 20 will decrease and particles from the outside will increase.

[0035] In addition, since the narrowest portion 8 of the sealed hole 5 and the narrowest portion 24 of the packing 20 each have a tapered, sharp lead-in shape, the packing 20 can be easily inserted into the sealed hole 5 of the outer box 1 later. Furthermore, the packing 20 is not loosely fitted into the molded outer box 1 later, but is molded first and the outer box 1 is injection molded later, so that even if a sealed hole 5 of a complex shape is molded in the upper peripheral portion 3 of the outer box 1, the outer box 1 can be easily demolded. Furthermore, since the narrowest portion 22, wide portion 23, and narrowest portion 24 of the packing 20 have a pentagonal or deformed rhombus cross section, they have a sharp tapered shape and do not impede the flow of the thermoplastic resin for the outer box 1.

[0036] In the above embodiment, the outer box 1 is injection molded into a top-open box, but the present invention is not limited to this. For example, the container body may be molded into a front-open box that directly aligns and stores silicon wafers of φ300 mm, and an endless frame-shaped mounting groove for packing may be formed on the inner peripheral edge of the open front of the container body. In this case, the top cover 10 may be injection molded into a substantially plate-shaped cover that can be opened and closed detachably by using a molding material containing thermoplastic resin. Furthermore, the up-down, front-back, left-right directions of the substrate storage container in the above embodiment are directions based on the drawings, and can be appropriately changed as necessary. [Industrial Applicability]

[0037] The substrate storage container and manufacturing method thereof according to the present invention are used in the fields of electrical, electronic and semiconductor manufacturing. [Explanation of symbols]

[0038] 1 Outer box 2 Upper part (opening) 3 Periphery 4 Mounting groove 5 Close fitting hole 6 Narrow width part 7 Wide part 8 Narrowest part 10 Upper lid (lid body) 20 Packing 20A Gasket 21 Base 21A base 22 Narrow part 23 Wide section 24 Narrowest part 25 Standing piece 30 Packing

Claims

1. A substrate storage container in which a packing is sandwiched between an opening of an outer box capable of storing a substrate and a lid, A mounting groove for a packing is formed in the peripheral portion of the opening of the outer box, and a seal hole for the packing is formed in the mounting groove, and the seal hole is divided into a narrow portion connected to the mounting groove, a wide portion connected to the narrow portion and having a wider width, and a narrowest portion connected to the wide portion and having a narrower width, This substrate storage container is characterized in that the packing includes a base portion attached to a mounting groove of the outer box, a narrow portion connected to the base and in close contact with the narrow portion of the sealed hole of the outer box, a wide portion connected to the narrow portion and in close contact with the wide portion of the sealed hole, and a narrowest portion connected to the wide portion and in close contact with the narrowest portion of the sealed hole.

2. 2. A substrate storage container according to claim 1, wherein the outer box is molded from a molding material containing a thermoplastic resin, and the packing is molded from a molding material containing a thermosetting resin having excellent elasticity.

3. 3. A substrate storage container according to claim 2, wherein the cross sections of the narrow portion, the wide portion and the narrowest portion of the packing are substantially polygonal, and the narrowest portion is sharply formed and faces inward of the packing.

4. 3. A method for manufacturing a substrate storage container as described in claim 1 or 2, characterized in that a gasket is molded from a molding material containing an elastic thermosetting resin, the gasket is inserted into a mold for molding an outer box and the mold is clamped, the mold is filled with a molding material containing a thermoplastic resin, and then the molding material is cooled and solidified to form the outer box.

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