JP5626850B2 - Pellicle storage container - Google Patents

Description

The present invention prevents foreign matter from adhering to a photomask or reticle used in a photolithography process when manufacturing a thin film transistor (TFT), a color filter (CF), or the like constituting an LSI or a liquid crystal display (LCD). The present invention relates to a pellicle storage container that stores a pellicle used for the purpose. In particular, the present invention relates to a pellicle storage container for a large pellicle having an expanded pellicle film area of 1000 cm ² or more.

  The present invention relates to a pellicle storage container. First, the pellicle will be described.

  Conventionally, in a photolithography process at the time of manufacturing a fine circuit pattern such as a semiconductor device or a liquid crystal display, a dust-proof means generally called a pellicle is used to prevent foreign matter from adhering to a photomask or a reticle.

  The pellicle has, for example, a nitrous film having a thickness of 10 μm or less on the upper edge surface of a pellicle frame (hereinafter also referred to as a “pellicle frame”) having a shape matching the shape of a photomask or a reticle and having a thickness of about several millimeters. A pellicle film, which is a transparent polymer film such as cellulose, cellulose derivative or fluorine-containing polymer, is spread and bonded, and an adhesive is applied to the lower edge surface of the pellicle frame to form an adhesive layer for the mask. The protective film is adhered to the mask adhesive layer with a predetermined adhesive force.

  This mask adhesive layer is for fixing the pellicle to the photomask or reticle, and the protective film maintains the adhesive strength of the adhesive until the mask adhesive layer is used for that purpose. Therefore, the adhesive surface of the mask pressure-sensitive adhesive layer is protected.

  Such a pellicle is generally a manufacturer (hereinafter “used”) that manufactures a photomask or reticle (hereinafter also referred to as “mask”) from a manufacturer (hereinafter also referred to as “manufacturer”) that manufactures the pellicle. Also referred to as “person”.) The user, after pasting the pellicle on a mask or the like, supplies the mask or the like protected by the pellicle to a manufacturer that performs photolithography such as a semiconductor manufacturer or a liquid crystal panel manufacturer.

  When transporting this pellicle from the manufacturer to the user, in order to prevent foreign matter from adhering to the pellicle or to prevent the pellicle from being damaged, the pellicle is stored in a pellicle storage container comprising a tray and a lid on which the pellicle is placed. The pellicle storage container is generally stored in a dust-proof bag or the like and transported.

  By the way, the pellicle storage container needs to be sealed to prevent dust from adhering to the pellicle. In addition, the pellicle storage container is required to have a holding property capable of reliably holding the pellicle film in a non-contact state in order to prevent the lid from coming into contact with the pellicle film and contaminating or damaging the pellicle film.

  The pellicle storage container is usually manufactured by injection molding or vacuum forming a resin such as ABS or acrylic. These molding methods are used because the surface is smooth and there is little risk of adhesion of foreign matter and dust generation, because there is no joint and there is no risk of dust generation and foreign matter intrusion due to integral molding, even in complicated shapes This is because there are merits that it can be easily manufactured, and it is excellent in mass productivity and can be reduced in cost.

  A large pellicle storage container having a side exceeding 500 mm, which is mainly used for a liquid crystal pellicle, is generally a vacuum-formed synthetic resin sheet such as ABS or acrylic. This is because, in the injection molding in which the resin is injected at a high speed into the mold from one or several gates, the resin flow distance is too long, which makes it difficult to manufacture. On the other hand, in vacuum molding, since it can be formed simply by covering a mold with a heated resin sheet and vacuuming, a large pellicle storage container can be easily molded.

  However, in the case of vacuum forming, a thick material cannot be formed, and although ribs can be reinforced to some extent, basically only the sheets with the same thickness are bent, so there is a problem that it is difficult to make a highly rigid material. is there. For this reason, the pellicle storage container needs to suppress deformation of the lid and the pellicle mounting table by some method.

  Therefore, the present applicant suppresses the deformation of the pellicle storage container by attaching a reinforcing plate to at least one of the tray and the lid, and an air path is generated by locally applying a part of the mask adhesive layer. And a technique for preventing the tray or lid from coming into contact with the pellicle due to warping or deflection (see Patent Document 1).

  In addition, the present applicant proposes a technique for preventing deformation due to warping of the lid and tray due to high temperature during transportation of the pellicle storage container and providing a rib on at least one of the tray or the lid, and preventing foreign material intrusion. (See Patent Document 2).

  In addition, as a technique that does not use a reinforcing material, a pellicle storage container has been proposed in which a plurality of ribs that cross the diagonal line of the outer shape of the tray and do not intersect with other ribs are provided on the tray, thereby increasing the rigidity in the torsional direction in particular (patent) Reference 3).

  In addition, by providing a step on either the outside or the inside of the placement portion on which the pellicle frame 4b of the tray is placed, and placing the pellicle frame on the low step side, the pellicle becomes difficult to move during transportation, There has been proposed a pellicle storage container that reduces the risk of the adhesive material on the bottom surface of the pellicle frame being turned (see Patent Document 4).

JP 2005-49765 A JP 2000-173887 A JP 2008-139417 A JP 2007-47238 A

  As described above, the pellicle storage container is usually manufactured by injection molding or vacuum forming a resin such as ABS or acrylic.

  For this reason, in the conventional case of increasing the rigidity with another reinforcing plate, sufficient rigidity is obtained, but since the weight increases, the larger the area of the pellicle membrane, the more the rigidity from the container body to ensure sufficient rigidity. However, there was a problem that the reinforcing plate became heavier. Moreover, not only the reinforcing plate itself but also a part for fastening the reinforcing plate to the container body is required, and further, the man-hour for assembling this part to the container body is also required. Cost increases significantly.

  Further, in the conventional case where the rigidity is increased by a rib without using a reinforcing plate, the above-described problem of an increase in weight can be reduced. However, as in Patent Document 2, when the rib shape is an X shape provided in the direction connecting the diagonal lines of the outer shape, the rigidity in the torsional direction is extremely reduced due to the presence of intersections in the rib. There is a possibility that the tray is twisted along one of the diagonal lines and bent so that the apex of the pair approaches.

  The arrangement of the ribs as in Patent Document 3 is effective for the rigidity of the tray in the oblique torsional direction, but the vicinity of the apex of the rib exists near the center of the side, or the rib exists near the center of the side. Because it does not exist, when carrying the tray, when carrying around the fitting part on both short sides or both long sides by hand, or moving the center with a forklift, stress is applied near the center of the side. However, there is a problem that the rigidity in the direction of the vertical crease tends to be weak. Further, when an automatic take-out machine is used at the time of sticking to a mask with a large pellicle, the bottom surface of the tray tends to be relatively flat because it is necessary to suck and hold the bottom surface of the tray. On the other hand, when the ribs are arranged as in Patent Document 3, it is necessary to attach a plurality of ribs as the pellicle storage container becomes larger, so that a relatively flat surface is reduced and it is difficult to suck and hold the bottom surface of the tray. There was a problem of becoming.

For this reason, for example, a pellicle storage container for storing a large pellicle in which the area of the stretched pellicle film (hereinafter also simply referred to as “area”) exceeds 5000 cm ² and reaches 8000 cm ² , and further 10000 cm ² . In this case, it was not possible to provide sufficient rigidity and flatness of the bottom surface by using only the pellicle container main body without using the reinforcing body.

  Therefore, in order to solve the above-described problems, the present inventor provides a step on the mounting table on which the pellicle is mounted, and further provides a step on the inner side of the mounting table, so that the rigidity and the bottom surface of the pellicle storage container are reduced. The present invention was found by finding out that it has both flatness.

  That is, the pellicle storage container according to the present invention is a pellicle storage container having a tray on which a pellicle with a pellicle film stretched on one edge surface of a pellicle frame and a lid that covers the top surface of the tray. The tray has a bottom surface at the center of the tray, and a substantially square ring-shaped mounting table on which the pellicle is mounted by protruding from the periphery of the bottom surface of the center of the tray. A first step in the height direction of the pellicle frame is formed in the vicinity of the corner, and the first step has a vertical surface that rises from the bottom surface of the tray center in the height direction of the pellicle frame and crosses the diagonal of the outer shape of the tray. It is characterized by.

  According to the pellicle storage container according to the present invention, the first step is provided in the vicinity of the corner on the bottom side of the center of the tray in the mounting table, and the vertical surface of the first step is disposed in a direction crossing the diagonal line of the outer shape of the tray. The rigidity in the twist direction of the pellicle storage container can be increased. Accordingly, the rigidity of the pellicle storage container, particularly the rigidity and flatness of the mounting table can be ensured while ensuring a wide flat portion at the center of the tray, which is also suitable for tray suction when the pellicle is automatically taken out.

  And it is preferable that the 2nd level | step difference of the height direction of a pellicle frame is formed in the tray mounting base vicinity of a tray center bottom face. Thus, the rigidity of the container main body can be further increased by having the second step at the portion near the mounting table on the bottom surface of the tray center.

  Moreover, it is preferable to have the 3rd level | step difference in which the level | step difference of the height direction of a pellicle frame is formed in the outer edge side of the tray of a mounting base. Thus, by having the third step on the outer edge side of the tray of the mounting table, the rigidity of the container body can be further increased.

  Moreover, it is preferable that the corner | angular part of a 1st level | step difference, a 2nd level | step difference, and a 3rd level | step difference has a curvature radius. As described above, since the corners of the first step, the second step, and the third step have a radius of curvature, the stress acting on the corner can be dispersed.

  The pellicle storage container according to the present invention can ensure the rigidity of the pellicle storage container, particularly the rigidity and flatness of the mounting table, and is also suitable for tray suction when the pellicle is automatically taken out.

It is a schematic sectional drawing which shows the whole structure of the pellicle storage container which concerns on 1st Embodiment. It is a schematic front view which shows the tray of the pellicle storage container shown in FIG. It is the III-III sectional view taken on the line shown in FIG. It is a schematic sectional drawing which shows the whole structure of the pellicle storage container which concerns on 2nd Embodiment. It is a schematic front view which shows the tray of the pellicle storage container shown in FIG. FIG. 6 is a sectional view taken along line VI-VI shown in FIG. 5. It is a diagram for explaining a substantially triangular dimensions and the like, which is formed at the corner portion A of the first horizontal surface section 15 b.

[First Embodiment]
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic cross-sectional view showing the overall configuration of the pellicle storage container according to the first embodiment. FIG. 2 is a schematic front view showing the tray of the pellicle storage container shown in FIG. FIG. 3 is a cross-sectional view taken along the line III-III shown in FIG. In the drawings, the same or corresponding parts are denoted by the same reference numerals.

(Storage container)
As shown in FIG. 1, the pellicle storage container 1 includes a tray 2 on which the pellicle 4 is placed, and a lid 3 that covers the top surface of the tray 2 and covers the top surface of the tray 2. The tray 2 and the lid 3 are sealed and fixed with an adhesive tape or the like (not shown), or fixed with a fastener such as a clip or the like (not shown).

  The pellicle 4 stored in the pellicle storage container 1 includes a pellicle frame 4b having a substantially square ring shape that matches the shape of a photomask or a reticle (not shown), and a pellicle that is stretched and bonded to the upper edge surface of the pellicle frame 4b. A film 4a and a mask adhesive layer 4c applied to the lower edge surface of the pellicle frame 4b are provided. The pellicle film 4a is a transparent polymer film such as nitrocellulose, a cellulose derivative, or a fluorine-containing polymer having a thickness of 10 μm or less. The pellicle frame 4b is a pellicle frame having a shape matching a shape of a photomask, a reticle, or the like (not shown), and having a thickness and width of about several millimeters. The mask adhesive layer 4c is a layer coated with an adhesive, and a protective film is adhered to the surface of the mask adhesive 4c in order to maintain the adhesive strength of the adhesive. Therefore, the height direction of the pellicle frame 4b is the thickness direction of the pellicle frame 4b in which the pellicle film 4a is lifted, and shows the vertical direction in FIG.

  The material of the tray 2 and the lid 3 is preferably engineering plastic, reinforced plastic, metal or the like. From the viewpoint of weight reduction and moldability, plastic materials are often selected, and acrylic resin, acrylonitrile resin, polycarbonate resin, polyethylene terephthalate resin, acrylonitrile / butadiene / styrene resin, and the like can be used. Further, as the material of the tray 2 and the lid 3, in addition to the above resins, polyester resins other than polyethylene terephthalate, olefin resins such as polyethylene and polypropylene, polystyrene resins such as polystyrene, acrylonitrile / styrene resin, and the like can be used. The above resin may be imparted with antistatic properties in order to prevent foreign matter adhesion due to static electricity. Fiber reinforced plastics can also be used. When selecting a metal, aluminum etc. are used from a viewpoint of weight reduction.

  The tray 2 and the lid 3 can be manufactured by assembling such as vacuum molding, injection molding, or bonding using the above-described materials. In particular, when a large tray 2 or a lid 3 is employed, it is preferable to manufacture by vacuum forming. The thickness of the tray 2 or the lid 3 is preferably 1 mm to 10 mm.

  The dimensions of the tray 2 and the lid 3 are set according to the size of the pellicle 4 to be stored, and are slightly larger than the pellicle 4 to be stored.

  The lid 3 is preferably transparent or translucent for easy confirmation of the inside, and the tray 2 is preferably black for easy confirmation of attached foreign matter.

  The tray 2 and the lid 3 are fitted to each other at the peripheral edge, and the gap between the tray 2 and the lid 3 is preferably as narrow as possible in order to prevent entry of foreign matter from the outside.

  As shown in FIGS. 2 and 3, the tray 2 includes a tray central bottom surface 5 having an opening on the side facing the lid 3, a mounting table 6 on which the pellicle 4 is placed, and a fitting portion between the lid 3. 7.

(Steps on the mounting table)
The mounting table 6 protrudes from the periphery of the tray center bottom surface 5 to the top surface side of the tray 2 and to the side on which the pellicle 4 is mounted. The mounting table 6 has a step in the height direction of the pellicle frame 4 b, and the pellicle 4 is mounted on the highest horizontal portion 13 on which the mounting table 6 is raised.

  On the outer edge side of the tray 2 in the mounting table 6, a first vertical surface portion 14 a that falls substantially downward in the vertical direction from the horizontal portion 13, and extends substantially horizontally from the lower end of the first vertical surface portion 14 a toward the outer edge direction of the tray 2. A first horizontal surface portion 15a is formed, and a second vertical surface portion 16a is formed which descends substantially downward in the vertical direction from the tip of the first horizontal surface portion 15a and continues to the fitting portion 7.

  Also, on the side of the tray center bottom surface 5 in the mounting table 6, a first vertical surface portion 14 b that falls substantially downward in the vertical direction from the horizontal portion 13, and the center direction of the tray 2 (tray center bottom surface 5 from the lower end of the first vertical surface portion 14 b. A first horizontal plane portion 15b extending substantially horizontally toward the side), and a second vertical plane portion 16b falling further downward in a substantially vertical direction from the tip of the first horizontal plane portion 15b and continuing to the tray center bottom surface 5. ing.

  As described above, the horizontal portion 13, the first vertical surface portion 14a, the first horizontal surface portion 15a, and the second vertical surface portion 16a are provided on the outer edge side of the tray 2 of the mounting table 6 in the height direction step 8 (first step) of the pellicle frame 4b. 3 steps), and a step in the height direction of the pellicle frame 4b on the tray center bottom surface 5 side of the mounting table 6 by the horizontal portion 13, the first vertical surface portion 14b, the first horizontal surface portion 15b, and the second vertical surface portion 16b. 9 (first step) is formed.

  The lengths of the first vertical surface portions 14a and 14b, the second vertical surface portions 16a and 16b, and the first horizontal surface portions 15a and 15b vary depending on the size of the pellicle, and may be the same or different. It may be.

As the first horizontal surface section 15 four corners A of b disposed near the corner portion 6a of the mounting table 6 is substantially triangular shape, the second vertical surface portion 16b is, across the diagonal of the tray 2 outline position Is arranged. That is, step 9, together with the corner portion A of the first horizontal surface section 15 b disposed near the corner portion 6a of the mounting table 6 is formed in a substantially triangular shape, the diagonal of the second vertical surface portion 16b tray 2 outline It is arranged at the crossing position. By forming the step 9 in this way, the rigidity against the twist of the tray 2 is increased, and the flatness of the mounting table 6 can be maintained.

Here, with reference to FIG. 7, the dimensions of the substantially triangular shape or the like formed on the corner portion A of the first horizontal surface section 15 b.

  As shown in FIG. 7, the length of the long side of the outer shape of the tray 2 is X, and the length of the side parallel to the long side of the outer shape of the tray 2 in the substantially triangular shape formed at the corner A is x. In this case, the ratio (x / X) of the length x of the triangular shape parallel to the outer long side of the tray 2 to the length X of the outer long side of the tray 2 is preferably 5 to 30%, and 8 to 25%. More preferred is 10 to 20%. Thus, when the ratio of the length x of the triangular side parallel to the outer long side of the tray 2 to the length X of the outer long side of the tray 2 is within such a range, the rigidity is particularly increased, which is preferable. Therefore, in this embodiment, the ratio (x / X) of the length x of the triangular side parallel to the outer long side of the tray 2 to the length X of the outer long side of the tray 2 is 14%.

  Further, the length of the short side of the outer shape of the tray 2 is Y, and the length of the side parallel to the short side of the outer shape of the tray 2 in the substantially triangular shape formed at the corner A is y. In this case, the ratio (y / Y) of the length y of the triangular shape parallel to the outer short side of the tray 2 to the length Y of the outer short side of the tray 2 is preferably 10 to 40%, and preferably 15 to 35%. More preferred. Thus, if the ratio of the length y of the triangular side parallel to the outer short side of the tray 2 to the length Y of the outer short side of the tray 2 is within such a range, the rigidity is particularly increased, which is preferable. Therefore, in this embodiment, the ratio (y / Y) of the length y of the triangular side parallel to the outer short side of the tray 2 to the length Y of the outer short side of the tray 2 is 17.5%.

  Further, the angle formed by the diagonal line of the outer shape of the tray 2 and the second vertical surface portion 16b is preferably 30 to 110 °, more preferably 70 to 100 °, and most preferably 90 °.

  In addition, it is preferable that the level | step difference formed in the mounting base 6 has two steps or more, and since the mounting base 6 itself is narrow, 2-3 steps | paragraphs are more preferable. In view of moldability and the like, the level difference formed on the mounting table 6 is preferably 2 to 3 levels.

  Further, since the steps formed on the mounting table 6 are formed on both sides of the mounting table 6, the balance is good and the rigidity is high. And the flatness of the horizontal part 13 is also excellent. Since the horizontal portion 13 is a place where the pellicle frame 4b is placed, if the flatness of the horizontal portion 13 deteriorates, the adhesive material of the mask adhesive layer 4c follows the poor flatness of the horizontal portion 13. Deformation may cause problems such as an air pass when sticking to a mask.

(curvature radius)
The horizontal portion 13 and the first vertical surface portion 14a, the first vertical surface portion 14a and the first horizontal surface portion 15a, the first horizontal surface portion 15a and the second vertical surface portion 16a, the second vertical surface portion 16a and the fitting portion 7, and the horizontal portion 13 And the first vertical surface portion 14b, the first vertical surface portion 14b and the first horizontal surface portion 15b, the first horizontal surface portion 15b and the second vertical surface portion 16b, the second vertical surface portion 16b and the tray center bottom surface 5 each have a predetermined radius of curvature. It is preferable to have a connection structure. If they are connected at a right angle, the stress tends to concentrate on the apex, so that concentrated stress acts on this connecting portion. On the other hand, by providing a slight radius of curvature at the connecting portion, it is possible to disperse the stress, and it also works effectively for resin flow and mold release during molding. The radius of curvature is preferably 2 mm to 30 mm, more preferably 2 mm to 20 mm, and still more preferably 2 mm to 15 mm. Furthermore, the angles formed by these steps are not necessarily limited to 90 °, but are set as appropriate, and these angles may be obtuse from the viewpoint of manufacturing the tray 2.

(Fitting portion)
The fitting portion 7 includes an extended portion 7a extending in the horizontal direction from the outer peripheral edge of the mounting table 6, and an outermost extended portion 7b extending upward from the peripheral end portion of the extended portion 7a. The fitting portion 7 has a shape corresponding to the lid 3 and can be brought into close contact with the lid 3 when the tray 3 is covered with the lid 3. The fitting portion 7 may further include an edge portion (not shown) extending outward from the peripheral end portion of the outermost extending portion 7b.

[Second Embodiment]
Next, a pellicle storage container according to the second embodiment will be described with reference to FIGS. 4 and 5. FIG. 4 is a schematic cross-sectional view showing the overall configuration of the pellicle storage container according to the second embodiment. FIG. 5 is a schematic front view showing a tray of the pellicle storage container shown in FIG. 6 is a cross-sectional view taken along line VI-VI shown in FIG.

(Storage container)
The pellicle storage container 21 is basically the same as the pellicle storage container 1 according to the first embodiment, and only the shape of the tray is different from the pellicle storage container 1 according to the first embodiment. For this reason, below, only a different part from the pellicle storage container 1 which concerns on 1st Embodiment is demonstrated, and other description is abbreviate | omitted.

  As shown in FIG. 4, the pellicle storage container 21 includes a tray 22 on which the pellicle 4 is placed and a lid 3 that covers the top surface of the tray 22. The tray 22 and the lid 3 are sealed and fixed with an adhesive tape or the like (not shown), or fixed with a fastener such as a clip or the like (not shown).

  As shown in FIGS. 5 and 6, the tray 22 includes a tray central bottom surface 25 having an opening on the side facing the lid 3, a mounting table 26 on which the pellicle 4 is placed, and a fitting portion between the lid 3. 27.

(Step on the bottom of the tray center)
A pair of steps 37 are formed in the height direction of the pellicle frame 4b on the tray center bottom surface 25 so as not to affect the automatic pickup suction. The step 37 is a substantially triangular recess disposed in the vicinity of the long side of the mounting table 26, and is connected to the vertical surface portion 37 a that falls vertically downward from the tray bottom surface 25 and the lower edge of the vertical surface portion 37 a. And a flat bottom surface portion 37b.

(Steps on the mounting table)
The mounting table 26 protrudes from the peripheral edge of the tray center bottom surface 25 to the side on which the pellicle 4 is mounted. The mounting table 26 has a step in the height direction of the pellicle frame 4 b, and the pellicle 4 is mounted on the highest horizontal portion 33 where the mounting table 26 is raised.

  On the outer edge side of the tray 2 in the mounting table 26, a first vertical surface portion 34 a that falls substantially vertically downward from the horizontal portion 33, and extends substantially horizontally from the lower end of the first vertical surface portion 34 a toward the outer edge direction of the tray 2. A first horizontal surface portion 35a to be taken out, and a second vertical surface portion 36a that continues from the tip of the first horizontal surface portion 35a further downward in a substantially vertical direction and continues to the fitting portion 27 are formed.

  Further, on the side of the tray center bottom surface 5 in the mounting table 26, a first vertical surface portion 34b that falls substantially vertically downward from the horizontal portion 33, and a center direction of the tray 2 (tray center bottom surface 5 from the lower end of the first vertical surface portion 34b). A first horizontal surface portion 35b extending substantially horizontally toward the side), and a second vertical surface portion 36b falling further downward in a substantially vertical direction from the tip of the first horizontal surface portion 35b and continuing to the tray center bottom surface 5. ing.

  As described above, the horizontal portion 33, the first vertical surface portion 34a, the first horizontal surface portion 35a, and the second vertical surface portion 36a form a step 28 in the height direction of the pellicle frame 4b on the outer edge side of the tray 2 of the mounting table 26. Then, a step 29 in the height direction of the pellicle frame 4b is formed on the tray center bottom surface 5 side of the mounting table 26 by the horizontal portion 33, the first vertical surface portion 34b, the first horizontal surface portion 35b, and the second vertical surface portion 36b. .

As the four corners of the first horizontal portion 35 b B disposed near the corners 26a of the mounting table 26 is in a substantially triangular shape, the second vertical surface portion 36b is, across the diagonal of the tray 2 outline position Is arranged.

Here, the corners range of dimensions of the substantially triangular shape is formed in the B of the first horizontal surface portion 35 b is essentially formed at the corner portion A of the first horizontal surface section 15 b described in the first embodiment This is the same as the range of the substantially triangular size (see FIG. 7). Therefore, in the second embodiment, the ratio (x / X) of the length x of the triangular side parallel to the outer long side of the tray 22 to the length X of the outer long side of the tray 22 is 15%, and the tray 22 The ratio (y / Y) of the length y of the triangular side parallel to the outer short side of the tray 22 to the length Y of the outer short side is 33%.

  Further, on the long side of the mounting table 26, only the first vertical surface portion 34b is formed, and the first horizontal surface portion 35b and the second vertical surface portion 36b are not formed.

That is, step 29, together with the corner portion of the first horizontal portion 35 b B disposed near the corners 26a of the mounting table 26 is formed in a substantially triangular shape, and the diagonal of the second vertical surface portion 36b Tray 2 outline It is arranged at the crossing position. A step 28 is not provided on the long side of the mounting table 26, but instead, a step 37 is provided in the vicinity of the mounting table 26 on the tray center bottom surface 5. As described above, on the long side of the mounting table 26, a step may be provided only on one side, or a step may be provided on both sides.

(curvature radius)
The horizontal portion 33 and the first vertical surface portion 34a, the first vertical surface portion 34a and the first horizontal surface portion 35a, the first horizontal surface portion 35a and the second vertical surface portion 36a, the second vertical surface portion 36a and the fitting portion 27, and the horizontal portion 33 And the first vertical surface portion 34b, the first vertical surface portion 34b and the first horizontal surface portion 35b, the first horizontal surface portion 35b and the second vertical surface portion 36b, the second vertical surface portion 36b and the tray central bottom surface 5 as well as the tray central bottom surface 25 It is preferable that each of the vertical surface portion 37a, the vertical surface portion 37a, and the bottom surface portion 37b has a connection structure having a predetermined radius of curvature. If they are connected at a right angle, the stress tends to concentrate on the apex, so that concentrated stress acts on this connecting portion. On the other hand, by providing a slight radius of curvature at the connecting portion, it is possible to disperse the stress, and it also works effectively for resin flow and mold release during molding. The radius of curvature is preferably 2 mm to 30 mm, more preferably 2 mm to 20 mm, and still more preferably 2 mm to 15 mm. Furthermore, the angles formed by these steps are not necessarily limited to 90 °, but are set as appropriate, and these angles may be obtuse from the viewpoint of manufacturing the tray 2.

(Fitting portion)
The fitting portion 27 includes an outer extending portion 27a extending in the horizontal direction from the outer peripheral edge of the mounting table 26, and an outermost extending portion 27b extending upward from the peripheral end portion of the outer extending portion 27a. The fitting portion 27 has a shape corresponding to the lid 3 and can be brought into close contact with the lid 3 when the tray 3 is covered with the lid 3. The fitting portion 27 may further include an edge portion (not shown) extending outward from the peripheral end portion of the outermost extending portion 7b.

  The preferred embodiments of the present invention have been described above with reference to the accompanying drawings, but the present invention is not limited to such examples. It is obvious for those skilled in the art that various modifications or modifications can be conceived within the scope of the idea described in the claims, and these naturally belong to the technical scope of the present invention. It is understood.

  For example, in the first embodiment, the second vertical surface portion 16b of the mounting table 6 has been described as being linear (planar), but is not limited to that shape. For example, 16b in FIG. As shown by ', a concave arcuate shape (curved surface) may be used, and as shown by 16b' 'in FIG. 7, a convex arcuate shape (curved surface) may be used. In this case, the angle formed between the diagonal line of the outer shape of the tray 2 and the second vertical surface portion 16b is equal to the tangent line of the second vertical surface portion 16b at the position where the diagonal line of the outer shape of the tray 2 intersects the second vertical surface portion 16b. It is represented by the angle formed with the diagonal line. The same applies to the second vertical surface portion 36b of the second embodiment.

  Further, the mounting table 6 does not necessarily have a complete annular shape. For example, the mounting table 6 may be formed by only a portion parallel to the short side of the outer shape of the tray 2, or only a portion parallel to the long side of the outer shape of the tray 2 or the tray. You may form only in the part parallel to the short side of 2 external shape. Further, the mounting table 6 is a U-shape centered on a short side of the outer shape of the tray 2 or a portion parallel to the long side, and may be formed to face each other.

  Specific examples and comparative examples will be shown below, and their evaluation will be described in detail.

[Example 1]
Example 1 employs the pellicle storage container according to the second embodiment, and the tray of this pellicle storage container has an ABS so that the outer diameter is 1000 mm wide × 1600 mm deep, 60 mm high, and 6 mm thick. A resin vacuum molded product was used. Then, the step on the outer edge side of the mounting table has two steps, the step on the bottom surface side of the tray center of the mounting table has two steps, and the first horizontal surface portion near the corner of the mounting table has a triangular shape, and further the center of the tray A triangular step was provided on the bottom surface (see FIG. 4).

  1. Place the pellicle storage container of Example 1 described above on the desk in the laboratory, pinch and fix the three corners of the pellicle storage container together with the desk, and lift the remaining one corner by 2. Pulling with a force of 5 kgf, the warpage (deformation amount) of the pellicle storage container was measured with a metal scale. The film wrinkle at that time was confirmed. Table 1 shows the measurement results.

[Example 2]
Example 2 employs the pellicle storage container according to the first embodiment, and the tray of this pellicle storage container has an ABS so that the outer diameter is 950 mm wide × 1400 mm deep, 85 mm high, and 5 mm thick. A resin vacuum molded product was used. The steps on the outer edge side of the mounting table were set to two steps, and the steps on the tray inner bottom surface side of the mounting table were set to two steps (see FIG. 2). Table 1 shows the measurement results.

[Comparative Example 1]
Comparative Example 1 is the same as in Example 1 except that the pellicle storage container of Example 1 is provided with a step only on the bottom surface of the center of the tray disposed inside the mounting table without raising the mounting table. It was. Table 1 shows the measurement results.

[Comparative Example 2]
Comparative Example 2 was performed in the same manner as in Example 1 except that the pellicle storage container of Example 1 had a raised mounting table with no step. Table 1 shows the measurement results.

[Comparative Example 3]
Comparative Example 3 was performed in the same manner as in Example 1 except that the pellicle storage container in Example 2 had a raised mounting table with no step. Table 1 shows the measurement results.

表１に示すように、比較例１〜３は、何れも膜シワが確認されたが、実施例１及び２は、何れも膜シワが確認されなかった。

As shown in Table 1, in Comparative Examples 1 to 3, film wrinkles were confirmed, but in Examples 1 and 2, film wrinkles were not confirmed.

  The present invention can be used as a pellicle storage container.

DESCRIPTION OF SYMBOLS 1 ... Pellicle storage container, 2 ... Tray, 3 ... Lid, 4 ... Pellicle, 4a ... Pellicle film, 4b ... Pellicle frame, 4c ... Mask adhesive layer, 5 ... Tray center bottom surface, 6 ... Mounting stand, 6a ... Corner 7, fitting portion, 7 a, extended portion, 7 b, outermost extended portion, 8, step (third step), 9, step (first step), 13, horizontal portion, 14 a, first vertical surface portion, 14 b ... 1st vertical surface part, 15a ... 1st horizontal surface part, 15b ... 1st horizontal surface part, 16a ... 2nd vertical surface part, 16b ... 2nd vertical surface part, 21 ... Pellicle storage container, 22 ... Tray, 25 ... Tray center bottom face, 26 ... mounting table, 26a ... corner, 26b ... mounting table, 27 ... fitting part, 27a ... extending part, 27b ... outermost extending part, 28 ... step (third step), 29 ... step (first step), 33 ... Horizontal portion, 34a ... First vertical surface portion, 34b ... First vertical surface portion, 35a First horizontal surface portion, 35b ... first horizontal surface portion, 36a ... second vertical surface portion, 36b ... second vertical surface portion, 37 ... step (second step), 37a ... vertical surface portion, 37b ... bottom surface portion, A ... corner portion, B ... Corner.

Claims (4)

A pellicle storage container having a tray on which a pellicle with a pellicle film stretched on one edge surface of a pellicle frame is placed, and a lid that covers the top surface of the tray,
The tray has a tray center bottom surface, and a substantially square ring-shaped mounting table on which a pellicle is mounted by protruding from the periphery of the tray center bottom surface to the top surface side,
In the mounting table, a first step in the height direction of the pellicle frame is formed in the vicinity of the corner on the bottom side of the tray center,
Wherein the first step includes a vertical surface that rising from the center of the tray bottom in the height direction of the pellicle frame, possess a horizontal portion extending substantially horizontally, and are disposed near the corners of the mounting table The pellicle storage container is characterized in that corners of the horizontal surface portion are formed in a substantially triangular shape, and the vertical surface crosses a diagonal line of the outer shape of the tray .   The pellicle storage container according to claim 1, wherein a second step in the height direction of the pellicle frame is formed in the vicinity of the mounting table on the bottom surface of the center of the tray.   3. The pellicle storage container according to claim 1, wherein a third step is formed on the outer edge side of the tray of the mounting table, wherein a step in the height direction of the pellicle frame is formed. The pellicle storage container according to any one of claims 1 to 3, wherein corners of the first step, the second step, and the third step have a radius of curvature.

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