JP2011007827A - Storage container for large precision member - Google Patents

Abstract

【Task】
Provided is a high-rigidity, lightweight, and low-cost large-sized precision member storage container that can store and transport large-sized precision members such as large pellicles, photomasks, and glass substrates while keeping them extremely clean.
[Solution]
In the large precision member storage container 1 that includes the tray 3 and the cover 2 that accommodates the large precision member 4 and covers and covers the entire precision member 4, at least the tray 3 of the tray 3 and the cover 2 is made of aluminum, aluminum alloy, or It is set as the large sized precision member storage container 1 comprised from a magnesium alloy.
[Selection] Figure 2

Description

  The present invention relates to a large precision member, particularly a container for storing a large pellicle having a side exceeding 500 mm, a large photomask or a glass substrate for a large photomask used in a photolithography process in liquid crystal manufacturing. It is.

  In the manufacture of semiconductors such as LSI and VLSI or the manufacture of liquid crystal displays, patterns are produced by irradiating a semiconductor wafer or liquid crystal master plate with light. A photomask or reticle (hereinafter simply referred to as a photomask) used at this time is used. If a foreign substance such as dust or dirt adheres to the above), the transferred pattern will be deformed, the transferred pattern will not be deformed, the edges will not be sharp, and the ground will be black. There is a problem that the dimensions, quality, appearance, etc. of the product are impaired. For this reason, these operations are normally performed in a clean room, but it is still difficult to keep the photomask clean. Therefore, in order to prevent foreign matter from adhering to the surface of the photomask, exposure is performed after the pellicle is attached to the photomask. In this case, the foreign matter does not adhere directly to the surface of the photomask, but adheres to the pellicle. For this reason, if the focus is set on the pattern of the photomask during lithography, the foreign matter on the pellicle becomes irrelevant to the transfer.

  In general, a pellicle is attached or bonded to the upper end surface of a pellicle frame made of aluminum, stainless steel, polyethylene, or the like with a pellicle film made of nitrocellulose, cellulose acetate, or a fluororesin that transmits light well. It is a thing. Furthermore, at the lower end of the pellicle frame, an adhesive layer made of polybuden resin, polyvinyl acetate resin, acrylic resin or the like for mounting on a photomask, and a release layer for protecting the adhesive layer until the pellicle is used ( Separator). On the other hand, a photomask is usually obtained by providing a light shielding film made of Cr or the like on one side of a glass substrate made of synthetic quartz or the like and drawing a desired circuit pattern on the light shielding film. The photomask after drawing is inspected for defects in the pattern and then highly cleaned, and a pellicle is pasted to protect the pattern while maintaining a very clean state. For this reason, the pellicle must not have any foreign matter attached to its inner surface before use, and since it is a material and structure that is virtually impossible to clean as described above, it can be used after storage after manufacture. It is necessary to prevent the adhesion of foreign matters as much as possible in the transportation up to. On the other hand, this need is the same for the photomask and the glass substrate before the photomask is manufactured.

  In recent years, the size of photomasks and pellicles has increased significantly with the increase in size of liquid crystal displays. As a matter of course, these storage containers also become large. Conventionally, storage containers made of resin by vacuum molding or adhesive bonding have been used for reasons such as low cost, light weight, capable of integral molding, and high degree of freedom in shape. . However, when the size of the storage container is increased, the weight of the storage object increases, and the amount of deformation with respect to the external force increases, so that the storage object in the storage container or the storage container itself is moved or rubbed. In order to prevent such dust generation in the container and deformation of the pellicle, it is necessary to increase the rigidity of the storage container. In response to this requirement, a method of attaching a metal reinforcing plate to at least one outer surface side of a tray and a cover of a resin pellicle storage container has been proposed (see Patent Document 1). Similar reinforcement methods have also been proposed for photomasks or glass substrates (see Patent Documents 2 and 3).

JP2009-037269 JP-A-2005-170507 JP 2006-184414 A

  However, the method for attaching the reinforcing plate to the outside of the resin container has the following problems. The main problem is related to cost and weight. The rigidity can be sufficiently increased by making the reinforcing plate highly rigid or increasing the amount of use. However, since the number of fastening points between the resin tray and the cover increases accordingly, the auxiliary parts required for assembly and the number of assembling steps increase, leading to a large cost increase. For example, in the case of a conventional storage container that has been conventionally used for a pellicle having an outer size of 1526 mm × 1748 mm × 8 mm and in which an aluminum alloy drawing mold material is attached as a reinforcing plate on the outside of a vacuum molded body made of ABS resin. Only about 10 hours were required for the assembly by 4 workers. Further, since the weight increases as the reinforcing plate is increased, the merit of using the resin as the material of the tray and the cover is lost as the rigidity is increased. Furthermore, although the resin tray and cover can be molded even with complicated shapes, the reinforcing plate to be attached must be a combination of relatively simple shapes in consideration of cost. Therefore, also from this point, it tends to lead to an increase in weight. For these reasons, excellent storage that has so far been lightweight and yet has low man-hours and cost for production while having high rigidity that can be transported in a clean state such as a pellicle, photomask or glass substrate. The container was not present.

  The present invention has been made in view of the above problems, and is highly rigid, lightweight and capable of storing and transporting a large precision member such as a large pellicle, photomask or glass substrate while keeping it in an extremely clean state. It aims at providing a low-cost large-sized precision member storage container.

  In order to solve the above-described object, according to one aspect of the present invention, there is provided a large-sized precision member storage container that includes a tray and a cover that accommodates a large-sized precision member and covers and covers the entire large-sized precision member. Is a large precision member storage container made of aluminum, aluminum alloy or magnesium alloy.

  Another embodiment of the present invention is a large precision member storage container in which at least the tray is manufactured by casting among the tray and the cover.

  Furthermore, another embodiment of the present invention is a large precision member storage container in which the thickness of the tray or cover is in the range of 4 to 10 mm in the plane portion.

  Another embodiment of the present invention is a large precision member storage container in which the surface of the tray or cover is coated and the surface roughness of the coating film is Ra 10 μm or less.

  Furthermore, another form of the present invention is a large precision member storage container whose coating film contains a conductive substance.

  Further, according to another aspect of the present invention, in the tray, the outer edge of the tray has a convex shape that protrudes toward the cover compared to the inner bottom surface on the inner side, and the back side of the outer edge of the convex shape has a concave shape. It is a large precision member storage container.

  Further, according to another aspect of the present invention, there is provided a resin plate having at least one opening in at least one of a tray or a cover made of aluminum, an aluminum alloy, or a magnesium alloy, and covering the entire surface in the opening. Or it is set as the large sized precision member storage container to which the glass plate is attached.

  Another embodiment of the present invention is a large precision member storage container in which a gap between a resin plate or glass plate covering an opening and a tray or cover is completely sealed with an adhesive resin.

  According to the present invention, there is provided a large precision member storage container having high rigidity, light weight, and low cost, capable of storing and transporting a large precision member such as a large pellicle, a photomask or a glass substrate while maintaining a very clean state. can do.

FIG. 1 is a perspective view of a large precision member storage container according to the first embodiment. FIG. 2 is an exploded perspective view of the pellicle stored in the large precision member storage container shown in FIG. FIG. 3 is a perspective view showing the tray shown in FIG. 2 and a partially enlarged cross section thereof. FIG. 4 is an exploded perspective view of a large precision member storage container according to the second embodiment storing a pellicle. FIG. 5 is a partial cross-sectional view of the vicinity of the buckle of the large precision member storage container according to the third embodiment. FIG. 6 is a partial cross-sectional view for explaining an incidental structure of the large precision member storage container according to each embodiment of the present invention. FIG. 7 is an exploded perspective view of a large precision member storage container according to the fourth embodiment when a photomask is stored as a large precision member. FIG. 8 is an exploded perspective view of a large precision member storage container according to the fifth embodiment when a photomask is stored as a large precision member. FIG. 9 is a partial cross-sectional view of the vicinity of the photomask fixing means in the large precision member storage container shown in FIG. 7 or FIG. FIG. 10 is an exploded perspective view of the large precision member storage container manufactured in the embodiment of the present invention, and is a view showing the pellicle to be stored.

  Below, each embodiment of the large sized precision member storage container of this invention is described.

1. First Embodiment In the first embodiment, the tray constituting the large precision member storage container is a cast of aluminum, aluminum alloy or magnesium alloy, and the cover is made of resin.

  FIG. 1 is a perspective view of a large precision member storage container according to the first embodiment. FIG. 2 is an exploded perspective view of the pellicle stored in the large precision member storage container shown in FIG.

  As shown in FIGS. 1 and 2, the large precision member storage container 1 according to the first embodiment is a thin, substantially box-shaped container, and the upper cover 2 and the lower tray 3 in a normal use state. Is provided. The cover 2 and the tray 3 can be opened and closed, and there is a space inside the large precision member storage container 1 when they are fitted and closed. The pellicle 4 as an example of a large precision member can be stored in the space. However, simply storing the pellicle 4 in the space causes the pellicle 4 to move within the large precision member storage container 1 during transportation, and a large number of foreign matters adhere to the pellicle 4 due to dust generation caused by rubbing or the like. There is a fear. For this reason, it is necessary to provide fixing means suitable for the stored items on the tray 3 and fix the stored items to the fixing means so that the stored items do not move during transportation.

  The cover 2 is a resin molded body having a recess on the tray 3 side. As a resin material constituting the cover 2, in addition to ABS resin, polyester resin such as acrylic resin, polycarbonate resin, and PET resin, polyolefin resin such as PE and PP, or polystyrene resin can be used. However, it is not limited to these. However, when the visibility of the pellicle 4 in the large precision member storage container 1 is taken into consideration, the cover 2 is preferably transparent (whether it is colorless and transparent or colored and transparent) or translucent. Therefore, it is particularly preferable to use an ABS resin or an acrylic resin as the material of the cover 2 in consideration of rigidity, processability such as molding / adhesion, cost, etc. in addition to transparency. More preferable.

  The cover 2 is preferably manufactured by vacuum forming, but in addition to vacuum forming, pressure forming by applying a gas pressure from the resin side to the mold side, and a combination of both the air forming and the vacuum forming. It can also be manufactured by vacuum forming, and can be appropriately selected in consideration of the moldability of the material, the complexity of the mold shape, and the like. Moreover, you may select shaping | molding methods other than the said shaping | molding method.

  Two gripping portions 20 are provided on both opposing short sides of the cover 2. The grip 20 is a component for opening and closing the cover 2 from the tray 3. If the grip 20 is configured to have an appropriate strength, it can be used for transporting the large precision member storage container 1 as a whole. However, since the cover 2 requires excessive rigidity, the cover 2 is usually used. It is preferable to design the gripping part 20 only for the opening / closing application. Further, in this embodiment, the gripping part 20 is bolted (not shown) to the cover 2 after being molded as a separate member from the cover 2, but the constituent members of the cover 2 are integrally molded. The shape of the gripping part may be used. Moreover, as the attachment position, you may make it equip with both long sides only with the both long sides which the cover 2 opposes, or the said both short sides.

  The tray 3 is an aluminum, aluminum alloy, or magnesium alloy molded body having a recess on the cover 2 side. As a manufacturing method of the tray 3, it is preferable to use casting, press working or the like, but it is particularly preferable to use casting. In the case of pressing, there is an advantage that a smooth and clean surface can be obtained. In this case, as the material, general wrought aluminum alloys, Al-Cu, Al-Mn, Al-Mg, Al-Mg-Si, and Al-Zn-Mg alloys can be used. In particular, from the viewpoint of workability such as forming and welding, it is preferable to select an Al—Mg system (JIS 5000 system) or an Al—Mg—Si system (JIS 6000 system). In the case of a magnesium alloy, the press formability is inferior to that of an aluminum alloy. However, when a warm press is used, Mg-Al-Zn-based AZ31 or the like can be preferably used.

  However, in the press working, in the case of performing a large molding as the object of the present invention, the processing cost of the mold becomes high, and the press machine to be used has a pressing force of several hundred tons or more. However, there is a demerit that the manufacturing cost becomes very high because it is almost equivalent to the automobile manufacturing equipment. Further, since thin plates having the same thickness are used for processing, sufficient rigidity cannot be ensured with only members. Therefore, it is necessary to provide many ribs to compensate for the lack of rigidity.

  On the other hand, when casting is adopted, a sand mold method, a lost wax method, a die casting method, or the like can be selected as a casting method. From these, an optimum one may be selected in consideration of the size and production amount of the large precision member storage container 1 to be manufactured, but sand casting that is superior in cost is particularly preferable. In casting, even if it is a complicated shape, a shape almost similar to a finished product can be obtained by a single molding, and there are only a few parts such as fixing means and attachment holes for the pellicle 4 that require machining. For this reason, casting has the advantage of very high productivity. As a material in the case of adopting casting, a general casting alloy can be suitably used. Among them, in the case of an aluminum alloy, Al—Si—Mg, Al—Si—Cu, Al—Si—Cu— An Mg-based alloy is particularly preferable. However, even if it is an Al-Si-Cu-based alloy, those having a very high Si content (for example, JIS AC8, AC9, etc.) are not preferable because of problems in Si segregation and machinability. In the case of magnesium alloy, Mg—Al—Zn (for example, ASTM AZ91), Mg—Ag (for example, ASTM QE22), and Mg—rare earth elements are particularly preferable from the balance of strength and workability.

  Further, the thickness of the tray 3 is preferably in the range of 4 to 10 mm, more preferably in the range of 5 to 8 mm in the plane portion. By setting the thickness of the flat surface portion to 4 mm (more preferably 5 mm) or more, there is no problem in the flow of molten metal during casting, and the molten metal can be sufficiently filled especially in the flat surface portion having a large area, thereby generating defects. Can be reduced. Further, by setting the thickness of the flat portion to 10 mm (more preferably 8 mm) or less, it is possible to suppress shrinkage during solidification and to make it difficult to cause defects due to shrinkage. In addition, it is possible to prevent an increase in cooling time and increase strength and productivity. In addition, the weight can be reduced. It should be noted that a portion requiring particularly rigidity, such as a bent portion and an outer peripheral portion other than the flat portion, is not limited to the above thickness range, and can be a desired thickness studied from the viewpoint of rigidity.

  Furthermore, when the entire tray 3 cannot be cast by a single casting, it is possible to manufacture the tray 3 by dividing the structure and joining them by fastening means such as welding or bonding, screws and rivets. It is. Although it is disadvantageous because the processing time of the joint is increased, in addition to cost reduction due to the small size of the mold, there is a problem in integral manufacturing because one casting is advantageous in casting quality. Where possible, split manufacturing may be employed.

  As described above, when casting, particularly sand mold casting, is employed, the surface of the casting becomes a casting surface having a large surface roughness. As it is, it is not suitable for storing products with a high degree of cleanliness because foreign matter tends to accumulate on the surface. In addition, since there are many pinholes or the like that are traces of outgassing during solidification, it is difficult to perform high cleaning. For this reason, it is preferable that the surface of the tray 3 after casting is subjected to a smoothing process such as polishing or sandblasting, and further, coating is performed after the smoothing so that the surface roughness is Ra 10 μm or less. Is particularly preferred. In this case, since the coating film is inevitably thickened, the foundation treatment of the casting surface is unnecessary, and the productivity can be further improved. Furthermore, it is preferable to include a conductive substance (carbon black, metal, etc.) in the coating film. When conductivity is imparted to the coating film, it is possible to effectively prevent charged foreign matter from adhering to the pellicle 4, and also to effectively prevent charging and electrostatic breakdown when the stored pellicle 4 is taken out. be able to.

  Two grip portions 30 are provided on each side of the short side and the long side of the tray 3. The grip 30 is for gripping the tray 3 or the large precision member storage container 1 when transporting it. In this embodiment, the gripping part 30 is fastened to the tray 3 with bolts (not shown) as a single part separate from the tray 3, but the shape of the tray 3 is devised and integrated. A molded structure may be used. These positions and shapes can be appropriately set in consideration of the overall weight.

  FIG. 3 is a perspective view showing the tray 3 shown in FIG. 2 and a partially enlarged cross section thereof. The partially enlarged cross section shown in FIG. 3 is an enlarged view of the area A indicated by the alternate long and short dash line after the tray 3 is cut along the dotted line X. Thus, the outer edge 31 of the tray 3 is formed so as to protrude toward the cover 2 as compared with the inner bottom surface 32 on the inner side, and the back side 33 has a concave shape on the contrary. By making the back side 33 concave without making the outer edge 31 into a simple thick shape, it is possible to reduce defects caused by shrinkage during casting and to reduce the weight of the tray 3. Further, the outer edge 31 is an area where the highest rigidity is obtained on the tray 3 due to the rib effect, so that it is most suitable for mounting the pellicle 4 as a stored item. It is preferable to finish the surface by cutting.

2. Second Embodiment In the second embodiment, both the tray and the cover constituting the large precision member storage container are cast from aluminum, aluminum alloy or magnesium alloy.

  FIG. 4 is an exploded perspective view of a large precision member storage container according to the second embodiment storing a pellicle.

  In this embodiment, the tray 3 has the same structure as that described in the first embodiment. The cover 2 is made of aluminum, an aluminum alloy, or a magnesium alloy as with the tray 3, but the material can be appropriately selected as with the tray 3 described in the first embodiment. Here, the material of the cover 2 and the tray 3 is not necessarily the same. For example, the material of the tray 3 can be an aluminum alloy so as to give particularly high rigidity, while the material of the cover 2 can be a magnesium alloy so as to be particularly lightweight at the time of opening.

  In this embodiment, the cover 2 is provided with an opening 21, and a resin plate 22 is attached so as to completely cover the opening 21. The gap between the resin plate 22 and the cover 2 is filled with an adhesive resin or the like so as not to generate dust from the gap and to prevent foreign matter from entering the large precision member storage container 1 by venting to the outside. It is preferably completely sealed. However, as a method for fixing the resin plate 22 to the cover 2, a seal member (O-ring or the like) may be interposed between the resin plate 22 and the cover 2, and the resin plate 22 may be fitted inside the cover 2. . Also in the embodiment having such an opening 21, the thickness of the cover 2 is in the range of 4 to 10 mm, further 5 to 5 for the same reason as the tray 3 described in the first embodiment. A range of 8 mm is desirable.

  A dotted line region 22 a illustrated in the cover 2 in FIG. 4 shows a state in which the resin plate 22 is fixed to the inside of the cover 2 in the direction of arrow B. Here, the number of the resin plates 22 is not limited to one, but may be plural for each opening 22 individually or in common for the plurality of openings 21. The shape of the opening 21 is not limited to the rectangle illustrated in FIG. 4, and may be another shape such as a circle. The resin plate 22 may have any shape as long as the opening 21 can be completely covered. Furthermore, in the illustration of FIG. 4, the resin plate 22 is attached from the inside of the opening 21, but may be attached from the outside. As the material of the resin plate 22, other than ABS resin, polyester resin such as acrylic resin, polycarbonate resin, and PET resin, polyolefin resin such as PE and PP, polystyrene resin, or the like can be used. As a selection from these materials, for example, when the cover 2 illustrated in FIG. 4 is provided with the resin plate 22, a transparent material such as ABS resin, acrylic resin, polycarbonate resin or the like is provided so that the pellicle 4 accommodated therein can be visually recognized. It is preferable to select a resin having better properties. It is further desirable to use a resin plate 22 having antistatic properties. Note that a glass plate or the like can be used instead of the resin plate 22 or in combination with the resin plate 22.

  On the other hand, although not illustrated in this embodiment, an opening may be provided in the tray 3 in the same manner as the cover 2, and the opening may be covered with a resin plate. When a resin plate is attached to the tray 3, it is desirable that the resin plate be colored, in particular black, in order to confirm foreign matter attached on the tray 3. As those materials, those obtained by coloring acrylic resin, ABS resin or the like into smoke brown, smoke gray or black can be used. In these cases, it is more desirable to impart antistatic properties. In addition, depending on the shape of the stored items, the tray 3 and the cover 2 can have the same form, and the tray 3 and the cover 2 can be distinguished from each other.

3. Third Embodiment As in the first embodiment, the third embodiment is a form in which the tray is formed of a cast of aluminum, an aluminum alloy, or a magnesium alloy, and the cover is made of resin. The cover is fixed with a buckle.

  FIG. 5 is a partial cross-sectional view of the vicinity of the buckle of the large precision member storage container according to the third embodiment.

  As shown in FIGS. 5 (5A) and (5B), as a buckle for fixing the cover 2 and the tray 3, the fixing portion 41 that can be fixed to the substantially vertical end surface 24 on the cover 2 side and the like on the tray 3 side. A buckle 40 composed of a drive unit 42 that can be fixed to the vertical end surface 34 or the like can be used. Further, when the cover 2 side has a shape in which the constituent members of the buckle cannot be fixed, for example, as shown in FIG. 5 (5B), the buckle 50 that can be fixed only by the substantially vertical end surface 34 on the tray 3 side. The cover 2 and the tray 3 can be fastened by hooking a part of the buckle 50 to the end 25 of the cover 2. Thus, the fastening means between the cover 2 and the tray 3 can be appropriately selected depending on the shape of the fixing portion of the cover 2 and the tray 3. In this embodiment, the cover 2 and the tray 3 or the buckles 40 and 50 fixed to the tray 3 are exemplified, but the cover 2 and the tray 3 are fastened by a clip or the like that can be completely removed from the tray 3 or the cover 2. Is also possible.

  Further, as shown in FIGS. 5 (5 A) and (5 B), a holding tool 5 for holding the pellicle 4 on the tray 3 is fixed to the protruding surface 31 a of the tray 3. Although only one holder 5 is shown in the drawing, a plurality of holders 5 are usually fixed along the outer edge 31 of the tray 3. The holding tool 5 may be any one as long as the pellicle 4 can be reliably fixed so as not to move in the tray 3 during transportation, and various types can be used. In this example, the pellicle 4 is fixed by inserting a pin supported by the holder 5 into a non-penetrating round hole provided on the side surface of the frame of the pellicle 4.

4). FIG. 6 is a partial cross-sectional view for explaining an incidental structure of the large precision member storage container according to each embodiment of the present invention.

  As a means for preventing foreign matter from entering the large precision member storage container 1 from the outside, a sealing material typified by the gasket 60 is sandwiched between the mating surfaces of the cover 2 and the tray 3, and the cover 2 and the tray are indicated by arrows F. It is preferable that the joint surfaces are brought into close contact with each other by fitting 3. As a similar means, a method such as attaching an adhesive tape to the entire outer periphery can also be selected.

  In addition, when a pressure difference occurs between the inside and outside of the large precision member storage container 1, a through-hole for adjusting the inside / outside air pressure is provided in order to facilitate release of the cover 2 and the tray 3, and further, air A filter 26 may be provided to prevent intrusion of foreign matter during the inflow.

  Furthermore, the caster 70 can be fixed to the bottom surface of the tray 3 to facilitate the movement of the large precision member storage container 1.

5. Fourth Embodiment In the fourth embodiment, as in the first embodiment, the tray is formed from a cast of aluminum, aluminum alloy or magnesium alloy, and the cover is made of resin. Instead of this, a photomask is stored.

  In each of the first, second, and third embodiments, the example in which the large pellicle 4 is accommodated has been illustrated. However, the object to be stored is not only the pellicle 4 but also a member that requires high cleanliness. For example, the present invention can be applied to a photomask, a glass substrate for a photomask, and the like. However, there is a large weight difference between the photomask and the pellicle 4. For example, the weight of a quartz glass substrate of 1620 mm × 1780 mm × 17 mm is about 110 kg, and the weight of the pellicle 4 of 1526 mm × 1748 mm × 8 mm corresponding to the quartz glass substrate is about 3 kg. For this reason, in the case of a container for storing a glass member such as a photomask, the individual member corresponds to a glass member such as a photomask while having a configuration according to each of the first, second and third embodiments. It is necessary to perform the designed.

  FIG. 7 is an exploded perspective view of a large precision member storage container according to the fourth embodiment when a photomask is stored as a large precision member.

  As shown in FIG. 7, the large precision member storage container 1 according to the fourth embodiment is a thin, substantially box-shaped container as in the first embodiment, and includes a cover 2 and a tray 3. The cover 2 and the tray 3 can be opened and closed, and the photomask 6 can be stored in a space formed when the cover 2 and the tray 3 are fitted and closed. Further, a fixing means is provided on the tray 3 so that the photomask 6 does not move during transportation, and the photomask 6 is fixed to the tray 3 using the fixing means. Since the contents regarding the material, structure, dimensions, and the like of the cover 2 and the tray 3 are the same as those in the first embodiment, the description thereof is omitted.

6). Fifth Embodiment In the fifth embodiment, as in the second embodiment, both the tray and the cover constituting the large precision member storage container are cast from aluminum, aluminum alloy or magnesium alloy. It is a form and accommodates a photomask instead of a pellicle.

  FIG. 8 is an exploded perspective view of a large precision member storage container according to the fifth embodiment when a photomask is stored as a large precision member.

  In this embodiment, the cover 2 and the tray 3 have the same material and structure as those described in the second embodiment. The cover 2 is provided with an opening 21, and a resin plate 22 is attached so as to completely cover the opening 21. The gap between the resin plate 22 and the cover 2 is filled with an adhesive resin or the like so as not to generate dust from the gap and to prevent foreign matter from entering the large precision member storage container 1 by venting to the outside. It is preferably completely sealed. Further, the resin plate 22 can be made of a highly transparent material, whereby the storage state of the internal photomask 6 can be easily visually recognized from the outside. The wall thickness of the cover 2 is desirably in the range of 4 to 10 mm, more preferably in the range of 5 to 8 mm, for the same reason as the tray 3 described in the first embodiment.

  FIG. 9 is a partial cross-sectional view of the vicinity of the photomask fixing means in the large precision member storage container shown in FIG. 7 or FIG.

  As shown in FIGS. 9A and 9B, a holder 7 for holding the photomask 6 on the tray 3 is fixed to the protruding surface 31 a of the tray 3. Although only one holder 7 is shown in the figure, in order to fix the photomask 6 that is heavier than the pellicle 4 described above, more trays 7 than the number required to fix the pellicle 4 are placed in the tray 3. It is preferable to prepare for. As shown in an enlarged view in FIG. 9 (9C), the holder 7 has a mechanism for fixing the outer peripheral edges of the upper and lower surfaces of the photomask 6 so as to be sandwiched between the inclined surfaces. The holder 7 includes a main body 71 fixed to the projecting surface 31 a, an upper projecting part 72 that is inserted into a space inside the main body 71 and projects above the main body 71, and a lower part of the main body 71. A downward projecting portion 73 projecting inward of the tray 3, and projecting inward of the tray 3 from the space inside the main body portion 71 and movable between the upper projecting portion 72 and the lower projecting portion 73. A movable protrusion 74 configured as above, an elastic body (for example, a spring) 75 that urges the movable protrusion 74 upward, and a screw hole provided in the upper protrusion 72, and an upper surface of the movable protrusion 74. A screw 76 is provided to abut against. The lower protrusion 73 has an inclined surface whose upper surface is inclined downward toward the inside of the tray 3. The movable protrusion 74 has an inclined surface whose lower surface is inclined upward toward the inside of the tray 3. When the screw 76 is turned and screwed in toward the movable protrusion 74, the movable protrusion 74 moves downward against the elastic body 75. On the other hand, when the screw 76 is rotated in the direction opposite to the above, the movable protrusion 74 moves upward according to the restoring force of the elastic body 75. Thus, by adjusting the height of the movable protrusion 74, the outer peripheral edges of the upper and lower surfaces of the photomask 6 having various thicknesses are sandwiched from the lower protrusion 73 in the vertical direction, and the photomask 6 is It can be fixed securely. Unlike the above, the elastic body 75 may be between the upper protrusion 72 and the movable protrusion 74 and bias the movable protrusion 74 downward.

7). Actions / Effects in Each Embodiment According to each of the above-described embodiments, in the large precision member storage container 1, at least the tray 3 of the tray 3 and the cover 2 is made of aluminum, aluminum alloy, or magnesium alloy. A lightweight and highly rigid storage container can be obtained. In particular, by manufacturing the large precision member storage container 1 by a casting method, a highly rigid storage container having a shape close to the final shape can be obtained by one casting without using a complicated reinforcing member. . Therefore, it is possible to obtain a low-cost storage container with a very small number of assembly steps. Moreover, the thickness of the flat part of the tray 3 manufactured by casting or both the tray 3 and the cover 2 is 4 to 10 mm (more preferably 5 to 8 mm), thereby suppressing the occurrence of defects, Productivity can be increased and weight can be reduced. Furthermore, by imparting conductivity to the coating film, it is possible to effectively prevent charged foreign substances from adhering to the large precision member, as well as charging and electrostatic breakdown when taking out the stored large precision member. Can be effectively prevented. In addition, it is possible to significantly reduce the adhesion of foreign matter to the large precision member to be housed by applying a coating with a surface roughness Ra of 10 μm or less with an antistatic paint. Further, by causing the outer edge 31 of the tray 3 to protrude from the inner bottom surface 32 of the tray 3 and making the back side 33 concave, defects that occur due to shrinkage during casting can be reduced and the weight of the tray 3 can be reduced. be able to. Furthermore, an opening 21 is provided in the casting (both the tray 3 or both the cover 2 and the tray 3), the opening 21 is sealed with a resin plate 22, and the gap is completely sealed with an adhesive resin. This prevents foreign matter from adhering to the large precision member and further reduces the weight. If the resin plate 22 is made of a highly transparent material, it is possible to easily check the storage status of the stored items (such as the pellicle 4 and the photomask 6) from the outside.

  Examples of the present invention will be described below. However, the present invention is not limited to the examples.

  For the purpose of storing the pellicle 4, a large precision member storage container 1 having an appearance as shown in FIG. The container 1 has a width of 1900 mm, a depth of 1700 mm, and a height (from the bottom surface of the tray 3 to the top surface of the cover 2) 180 mm. Details of the cover 2 and the tray 3 will be described below.

  FIG. 10 shows an exploded perspective view of a large precision member storage container manufactured in this embodiment, together with a pellicle to be stored.

  The cover 2 was integrally formed by vacuum forming using a transparent acrylic resin having a thickness of 3 mm and subjected to antistatic treatment. After molding, trimming around the cover 2 was performed, and then burrs and burrs were removed, and two handles 20 were attached to the side surfaces of both short sides from the inside by bolts (not shown). The tray 3 was manufactured by sand casting using an Al—Si—Mg based aluminum alloy for casting (JIS AC4CH).

  In casting, melting of the base material of Al-Si-Mg based aluminum alloy for casting (JIS AC4CH) is performed in the atmosphere using a siliconite electric furnace, and the crucible is used for the purpose of reducing porosity defects such as gas holes after molding. The inside was reduced in pressure by a vacuum pump to reduce the gas in the molten metal, and then cast. In consideration of improving the flow of hot water to the thin center part of the sand mold, the sand mold is provided in three places in total, the central part and the peripheral parts of both short sides, and is sufficient to prevent shrinkage. Secured hot water. Hot water is supplied at three locations at the same time. After cooling, the tray 3 is taken out from the sand mold, the pouring gate is removed by a large machining center, the outer dimensions are finished, the flat surface processing of the protruding surface 31a on which the pellicle 4 is mounted, and the hole processing for attaching the fixture 5 Went. Thereafter, cleaning was performed using a surfactant and tap water to remove casting sand, cutting oil, and foreign matters adhering during casting and machining, and heating was performed in a large oven to completely remove moisture.

  Next, after performing an appearance inspection of the casting and confirming that there are no casting defects such as cracks and shrinkage cavities, the tray 3 is held vertically in a clean environment, and a black antistatic paint (trade name: EC-06 / manufactured by Nagase ChemteX) was applied by a spray method and dried. At the time of coating, the coating amount at one time was controlled so as to be about 10 μm of coating film so that coating thickness unevenness and appearance defects due to dripping did not occur. After drying, repeated coating was repeated, and the final film thickness after the third coating was about 30 to 40 μm.

  The four openings 37 of the tray 3 are covered with a separately prepared antistatic black ABS resin plate 36 (product name: Toyolac Parrel / Toray Industries, Inc.) of 1480 mm × 1650 mm × 3 mm from above, and an epoxy adhesive (Product name: MOS7 / manufactured by Konishi Co., Ltd.) At this time, the adhesive was applied so that the resin plate 36 and the tray 3 did not have a gap between them. Further, after the adhesive was cured, the fixture 5 was adjusted on the tray 3 to a position where it could be fitted into a predetermined mounting hole of the frame of the pellicle 4, and attached with bolts. Thereafter, a handle 30 and a buckle 40 were attached as means for fastening the tray 3 and the cover 2.

  When the surface roughness of the painted surface of the tray 3 was measured with a stylus type surface roughness measuring machine, Ra = 3 μm, which was a smooth and clean flat surface that did not reflect the original casting surface. In addition, the appearance was also suitable with an appropriate matte tone and easy visual foreign matter inspection. As a result of the weight measurement, the cover 2 was about 23 kg, the tray 3 was 41 kg including the ABS resin plate (8 kg), and the total weight of the large precision member storage container 1 was 64 kg. Furthermore, except for the casting process and machining process performed by specialists, the number of man-hours required for assembly and manufacturing, including the adhesion of the ABS resin plate 36, is approximately one hour for two workers. As a result, the number of man-hours was greatly reduced.

  The cover 2 and the tray 3 of the large precision member storage container 1 manufactured in this way are carried into a class 10 clean room, thoroughly scrubbed using a surfactant and a PVA sponge, and then rinsed with pure water. And dried completely by natural drying. Thereafter, foreign matter inspection and appearance inspection were performed in a dark room. Since the cover 2 is a resin-made large vacuum molded product, there was no particular problem. The tray 3 is also clean on the painted surface, the surface of the ABS resin plate 36, and the joint between the casting and the ABS resin plate 36. In addition to casting defects such as shrinkage nests, molten metal flow marks, blow holes, etc. Also, no adhesion defects were observed at the joints, and the appearance was good.

  Therefore, a pellicle 4 separately manufactured was stored in the large precision member storage container 1 and a transportation test was performed. The pellicle 4 used here is an A5052 aluminum alloy pellicle frame with an outer dimension of 1526 mm x 1748 mm, an inner dimension of 1493 mm x 1711 mm, and a height of 6.2 mm and made of black anodized. A 6-mm thick silicone adhesive layer having a thickness of 6 mm is formed, and a 6 μm-thick fluororesin pellicle film formed by die coating is attached to the opposite end face with a silicone adhesive. The mask adhesive layer is a PET film separator having a thickness of 125 μm, which is a separator cut into approximately the same size as the pellicle frame and coated with a fluorine-modified silicone release agent. The pellicle 4 was inspected for foreign matter in a dark room, and the position of the attached foreign matter was accurately described on a map, and then stored in the manufactured large precision member storage container 1.

  After the pellicle 4 was stored, the two large-sized precision member storage containers 1 were transported by two workers, but no deformation or stagnation of the container 1 was felt in normal handling. Therefore, three workers were arranged on both long sides and the large precision member storage container 1 was intentionally twisted by six persons, but the inner pellicle film was kept flat. As it was, no signs suggesting deformation of the container 1 such as wrinkles or slack of the film were observed.

  Next, the large precision member storage container 1 in which the pellicle 4 was stored was double-packed in an antistatic PE packing bag, then taken out from the clean room and packed in a reinforced cardboard box. The transportation test was carried out three times, including loading and unloading, by packing the package from Takasaki City, Gunma Prefecture to Kitakyushu City, Fukuoka Prefecture, using the expressway. The internal pellicle 4 was subjected to an appearance inspection and a test for inspecting for the presence of attached foreign matter. As a result, no damage was confirmed in both the pellicle frame and the pellicle film. Further, the position and number of foreign matters on the film were not changed from those before transport. From these results, the large precision member storage container 1 is lightweight and has a sufficient rigidity for transporting the large precision member including the pellicle 4 in a clean state while having a small number of assembly steps at the time of manufacture. It was confirmed that

  The present invention can be used to house or transport a precision substrate, such as a pellicle or glass photomask.

1 Large precision member storage container 2 Cover 3 Tray 4 Pellicle (an example of large precision member)
6 Photomask (an example of a large precision member)
21 Opening 22 Resin Plate 31 Outer Edge 32 Inner Bottom 33 Back Side 36 ABS Resin Plate 37 Opening

Claims (8)

In a large precision member storage container that includes a tray and a cover that accommodates a large precision member and covers the entire precision member,
Of the tray and the cover, at least the tray is made of aluminum, an aluminum alloy, or a magnesium alloy.   The large precision member storage container according to claim 1, wherein at least the tray of the tray and the cover is manufactured by casting.   The large-sized precision member storage container according to claim 2, wherein the thickness of the tray or the cover is in the range of 4 to 10 mm in the plane portion.   The large precision member storage container according to any one of claims 1 to 3, wherein a surface of the tray or the cover is painted, and a surface roughness of the coating film is Ra 10 µm or less.   The large-sized precision member storage container according to claim 4, wherein the coating film contains a conductive substance.   2. The tray according to claim 1, wherein an outer edge of the tray has a convex shape protruding toward the cover as compared to an inner bottom surface located inward of the tray, and a rear side of the convex outer edge is a concave shape. The large precision member storage container according to any one of items 1 to 5.   At least one of the tray or the cover made of aluminum, aluminum alloy, or magnesium alloy has at least one opening, and a resin plate or a glass plate that covers the entire surface is attached to the opening. The large precision member storage container according to any one of claims 1 to 6, wherein the container is a large precision member storage container.   The large precision member storage container according to claim 7, wherein a gap between the resin plate or the glass plate covering the opening and the tray or the cover is completely sealed with an adhesive resin. .

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