HK1113121B - Pellicle storage container - Google Patents

Description

Protective film assembly storage container

Technical Field

The present invention relates to a container for storing pellicle components for lithography, which can store, store and transport pellicle components for lithography used as dust-proof devices in the manufacture of products such as semiconductor devices, printed circuit boards, liquid crystal displays, etc.

Background

In the manufacture of semiconductor such as LSI and super LSI or products such as liquid crystal display panels, a semiconductor wafer or a liquid crystal original plate is irradiated with light to form a pattern, but if dust adheres to a photomask or reticle (hereinafter simply referred to as a photomask), the dust absorbs the light and bends the light, so that the transferred pattern is deformed and the edge is roughened, and the substrate is blackened to deteriorate the size, quality, appearance, and the like.

Therefore, these operations are usually performed in a clean room, but even so, it is difficult to keep the mask clean frequently. Then, the inventors attached a pellicle as a dust-proof device to the surface of the mask and then performed exposure. At this time, the foreign matter is not directly attached to the mask surface but attached to the pellicle, so that the foreign matter on the pellicle does not affect the transfer printing as long as the mask pattern is focused in the photolithography step.

In general, the pellicle is formed by forming a transparent pellicle film from a substance having good light transmittance, such as nitrocellulose, cellulose acetate, or fluororesin, forming a pellicle frame from a substance such as aluminum, stainless steel, or polyethylene, and adhering the pellicle to the upper end surface of the pellicle frame. Next, an adhesive layer made of polybutylene resin, polyvinyl acetate resin, acrylic resin, or the like, which is attached to the mask, and a release layer (spacer) for protecting the adhesive layer are provided at the lower end of the pellicle frame.

However, although the closed space formed by attaching the pellicle to the mask has an effect of preventing foreign matter from entering the mask from the outside, it is difficult to prevent foreign matter from adhering to the mask surface if the foreign matter adheres to the pellicle itself and is inside the closed space. Therefore, in addition to the high cleanability of the pellicle itself, the pellicle container used for storage and transportation is strongly required to have the performance of maintaining the cleanability. Specifically, a structure which is excellent in antistatic performance, is made of a material having a small amount of dust generation when rubbed, and can prevent contact between the pellicle and the component as much as possible, and a high-rigidity structure which can prevent deformation when an external force is applied are required.

The container for housing a pellicle is generally manufactured by injection molding or vacuum molding a resin such as Acrylonitrile Butadiene Styrene (ABS) resin or acrylic acid. The molding methods have advantages of smooth surface, less contamination of foreign matters or dust, no seam in one-piece molding, less contamination of dust or foreign matters, easy production even if the shape of the article is complicated, excellent mass productivity, and low cost.

A container for housing a pellicle for semiconductor or printed circuit board, which has an outer shape side of about 200 to 300mm, is generally manufactured by injection molding. As described above, in order to keep the pellicle storage container clean, it is required to have high rigidity that is hard to deform even when an external force is applied, but there is a problem that rigidity is less in the pellicle storage container having the side length of 200 to 300 mm. In the prior art, a small container is relatively easy to ensure its rigidity, and the thickness of an important part can be easily increased by changing the thickness of a part by injection molding.

On the other hand, a large pellicle unit container mainly used for a pellicle unit for liquid crystal having a side length of more than 500mm is generally manufactured by vacuum forming a synthetic resin sheet such as ABS or acrylic. This is because, in the case of injection molding in which resin is injected into a mold at a high speed from one or a plurality of gates, the resin flow distance is too long, which makes the production difficult. In the vacuum molding method, a heated resin sheet is placed on a mold and vacuum suction molding is performed, so that even a large article can be easily produced.

However, the vacuum forming method cannot form a thick wall, and although the rib portion can be used for some degree of reinforcement, it is basically produced by bending a sheet having the same thickness, and thus it is difficult to produce a high-rigidity article using the method.

Examples of such ribs are disclosed in patent document 1 and the like, for a container body.

The conventional reinforcing ribs are basically X-shaped members disposed in the direction of diagonal lines 54a and 54b connecting the outer shapes, as shown in fig. 5. However, the ribs of the intersecting X-shape, contrary to the expectation, cause a low rigidity in the twisting direction due to the presence of the intersecting portion (continuous portion) 59, and the tray is twisted and bent along either one of the diagonal lines as shown in fig. 6 to bring the opposite apexes closer.

In the rib portions manufactured by the vacuum forming method, the rib portions are secured in rigidity by the longitudinal direction surface of the bending, but the other rib portions intersecting (continuing) cut the longitudinal direction surface. Then, the rib not only cuts the target rib to neutralize the effect, but also becomes a bending point (line) itself to increase the degree of deformation.

Therefore, sufficient rigidity cannot be ensured only by the rib, and as shown in patent document 2, it is necessary to ensure rigidity by connecting to another reinforcement.

[ patent document 1] Japanese patent application laid-open No. 2000-173887

[ patent document 2] Japanese patent application No. 2005-081533

Disclosure of Invention

Problems to be solved by the invention

As described above, when other reinforcing members are used, sufficient strength can be obtained, but various operational disadvantages occur. The most serious of these is the increase in weight, which in almost all cases is heavier than the container body in order to ensure sufficient rigidity. Then, the weight increases, which causes great inconvenience in handling such as packaging and transportation.

Further, not only the reinforcing member itself but also a part for connecting the reinforcing member to the container body and a work flow for attaching the reinforcing member to the container body are required, so that the cost is significantly increased as compared with the case of only the container body. In addition, there are other problems concerning cleanliness such as difficulty in cleaning the gap between the reinforcing member and the container main body.

However, there is no container for receiving a pellicle assembly having sufficient rigidity only by a container body without using a reinforcement.

In view of the above, an object of the present invention is to provide a light-weight and low-cost container for housing a pellicle, which has sufficient rigidity to withstand external impacts during storage and transportation and to prevent foreign matter from adhering to the pellicle housed inside, without using any other reinforcement.

Means for solving the problems

The protective film assembly container of the invention is composed of the following components: a container body on which a pellicle is placed; a lid body which is covered with the protective film assembly and is engaged with the container body in a manner that the peripheral edge portions thereof are fitted to each other, characterized in that: the container body is formed of a resin sheet, and the container body is provided with a plurality of ribs that intersect a diagonal line of the outer shape of the container body, each rib does not intersect another rib of the plurality of ribs, and an angle between each rib and the intersecting diagonal line is 30 degrees or more (claim 1).

Here, the angle between the rib and the transverse diagonal line is preferably 30 degrees or more (option 2). And a fork, wherein the rib portion can not cross other rib portions, but the end portion can be connected with other rib portions or a pedestal for carrying the protective film assembly (scheme 3).

Then, if the rib portions have different heights and have different height regions (claim 4), it is possible to form an excellent shape that can exhibit the rib effect and maximize the rigidity.

Comparing the efficacy of the prior art

According to the present invention, since the rigidity of the container body, particularly the rigidity in the torsional direction, can be significantly increased by the appropriate arrangement of the rib portions without using a reinforcing member, a light-weight and highly rigid container for housing a pellicle can be produced at low cost.

The invention is particularly effective when being applied to a large protective film component containing container with the side length exceeding 500 mm. However, the size is not limited, and a small container having a side length of 200mm can be used as long as the container is a container for housing a pellicle assembly formed by molding a resin sheet. Although the small container has less problem of rigidity, if the rigidity can be further improved by the structure, the sheet thickness can be made thinner, the weight can be reduced as compared with the large container, and the cost can be reduced.

Drawings

Fig. 1 is a schematic view showing an example of a rib structure of a container body for a pellicle according to the present invention.

Fig. 2 is a perspective view showing the entire structure of the pellicle assembly storing container of the present invention.

Fig. 3 is a plan view (a) showing another embodiment of the rib structure of the container body for housing a pellicle according to the present invention, and a sectional view (b) taken along line a-a of (a).

Fig. 4 is a perspective view showing a rib structure of the container body for housing a pellicle according to the present invention.

Fig. 5 is a plan view showing an example of a rib structure of a conventional pellicle film assembly receiving container body.

Fig. 6 is a perspective view illustrating a modified form of a conventional pellicle assembly container body.

Fig. 7 is a plan view showing an example of a container body for a pellicle assembly using a conventional aluminum reinforcement.

Fig. 8 is a plan view showing one embodiment of the container body for housing a pellicle according to the present invention.

Fig. 9 is a plan view showing an example of a container body for a pellicle assembly using a conventional rib structure.

Description of the main reference numerals

11 container body for protective film assembly

12 mounting table for pellicle

13 Rib

14 diagonal of container body profile

The a rib forms an angle with the transverse diagonal

21 protective film assembly container body

22 cover body

23 clamping device

31 protective film assembly container body

32 protective film assembly carrying bench seat

33a, 33b, 33c, 33d ribs

34 rib

35 diagonal line of container body profile

41 Rib

Plane generated by 42 step difference part

51 protective film assembly container body

52 stand for pellicle

53a, 53b Ribs

54a, 54b diagonal of the container body profile

55. 56, 57, 58 container body corner part

59 intersection of ribs

71 protective film assembly container body

72 protective film assembly fixing bolt

73 bolt support part

74 reinforcing body fixing tool

75 aluminium alloy reinforcing body (short)

76 aluminum alloy reinforcing body (Long)

77 protective film assembly

81 protective film assembly container body

82 protective film assembly mounting table

83 Rib

84 Rib

85 (for protective film assembly) fixing bolt

86 bolt supporting part

87 pellicle

91 protective film assembly container body

92 protective film assembly mounting table

93 rib

94 protective film assembly fixing bolt

95 bolt supporting part

96 protective film assembly

Detailed Description

Hereinafter, an embodiment of the pellicle assembly storing container according to the present invention will be described with reference to the drawings.

Fig. 1 is a schematic view showing an embodiment of a pellicle container (main body) according to the present invention, and fig. 2 is a perspective view of the whole pellicle container. Fig. 5 is a view showing a container body having a rib structure used in the related art, and fig. 6 is a view showing a deformation state when a corner of the container body of fig. 5 is lifted.

In the conventional pellicle unit container body 51 (fig. 5), when an external force is applied in a twisting direction, for example, when a force for lifting the corner portion 57 upward is applied, the container body 51 is bent along the diagonal line 54 b.

In this case, the rib 53b should originally resist the torsional deformation, but the cross rib 53a cuts the rib at the cross portion 59, and therefore, cannot exert sufficient resistance.

Further, since the cross rib 53a almost coincides with the diagonal line 54b, the rib itself becomes most easily bent, and becomes a deformation reference point as shown in fig. 6.

The present invention has been completed after various shape trials and comparative studies.

In fig. 2, a pellicle (not shown) is placed on a pellicle container body 21 and covered with a lid 22. Then, the lid 22 and the container body 21 are sealed and fixed by an adhesive tape (not shown) or the like, or fixed by a fastening tool such as a jig 23.

The container body 21 and the lid 22 can be formed by bonding resin plates, but in view of cleanliness, mass productivity, etc., a vacuum forming method is preferable.

The lid and the container body may be made of any suitable material selected from resins such as acrylic, ABS, and PVC, but materials capable of preventing static electricity are preferably used in order to reduce adhesion of foreign matter due to static electricity. Then, the cover is preferably transparent or translucent to confirm the inside condition, and the container body is preferably black to confirm whether foreign materials are attached.

The lid 22 is fitted to the peripheral edge of the container body 21, and the gap is preferably minimized to prevent foreign matter from entering from the outside. The container body 21 is then preferably provided with a plurality of ribs 13 which are arranged in a diagonal line 14 as shown in fig. 1, transversely to the outer shape of the container body, and which do not intersect with other ribs. In the example of fig. 1, the number of the ribs 13 is 4, but it does not matter if 4 or more ribs are provided, and the ribs may be provided as appropriate according to the size or the outer shape of the container body.

In this case, the angle a formed by the rib 13 and the diagonal line 14 is preferably 30 degrees or more, and more preferably as close to 90 degrees as possible. When an external force in a twisting direction acts on the container body, the rib portion exhibits the highest resistance when the angle across the diagonal line is 90 degrees, and when the angle is 30 degrees or less, not only the effect becomes extremely small, but also the rib portion itself is likely to become a bent line of torsional deformation.

Fig. 3 shows another embodiment of the rib arrangement. As in fig. 1, ribs 33a, 33b, 33c, and 33d crossing the diagonal line 35 are provided, and the end portions of the ribs are connected to the pellicle mounting table 32 and the other ribs, although the ribs do not cross the other ribs. The connection at the end of the rib hardly causes a problem of reduction in rigidity.

The ratio of the long side to the short side of the profile of a commonly used pellicle is in almost all cases more stable than the design in the example of figure 1.

Further, in the rib 33c of fig. 3(a), as shown in a sectional end view a-a (fig. 3(b)) or fig. 4, the height of the rib is not necessarily constant, and it is preferable to have regions of different heights.

When the rib is deformed by twisting, the rib itself is easily deformed as a curved line as shown in fig. 4 and 6, but if another surface (a flat surface 42 due to a step) is provided in the rib 41, the amount of deformation of the rib body can be reduced. In other words, the surface 42 can be said to constitute another reinforcing rib for reinforcing the rib 41.

The width, height, arrangement, number, cross-sectional shape, etc. of the ribs may be appropriately set in accordance with the required rigidity and formability of the container body, and the illustrated embodiments are not limited at all.

Examples

Hereinafter, examples of the present invention will be described, but the present invention is not limited thereto. The antistatic ABS (black) sheet was used to form a protective film module container body 81 having a shape shown in fig. 8 by vacuum forming.

The storage container body 81 had a size of 690X 540mm in outer shape, 30mm in height and 3mm in sheet thickness. The width of each rib was 20 mm. In addition to the rib 83 crossing the diagonal line, a rib 84 disposed substantially parallel to the rib 83 is provided in the center portion for reinforcement.

The rib 83 is provided with a step similar to the perspective view of fig. 4, and the height of the entire rib is 30mm and the height of the step is 20 mm.

The connection angle of the rib 83 to the ceiling surface and the stepped surface is preferably a right angle, but is set to 60 degrees in consideration of formability. The rib 84 disposed at the center is reduced to 20mm in height to prevent the protective film from shaking and contacting during conveyance.

Then, in order to fix the protective film assembly in the container body, a fixing pin 85 made of polyphenylene sulfide (PPS) and a pin support portion 86 made of ABS are attached by bolts (not shown) in accordance with the position of the accommodated protective film assembly. The fixing latch 85 is inserted into the latch support portion 86 so as to be supported, and is formed into a configuration disengageable by the locking mechanism.

The fixing pin 85 has a structure in which a tip end thereof is inserted into a jig hole (not shown) provided in a side surface of the pellicle frame 87, and a ring-shaped cushion member (not shown) made of viton (trademark of fluorinated rubber manufactured by dupont) for preventing dust emission is attached to a surface in contact with the pellicle frame 87.

Thereafter, the film module is cleaned with clean pure water in a clean room, and the pellicle film 87 is actually placed on the pellicle film mounting table 82 of the prepared pellicle film housing container body 81 and fixed by the fixing pins 85.

Then, the container body 81 was placed on the horizontal fixed plate, and 1 corner of the body was slightly lifted upward. As a result, the container body 81 is hardly distorted by torsion, and the mounted pellicle is still firmly fixed to the surface of the container body 81 without any change.

Further, the fixing pin 85 is removed, and the jig hole into which the fixing pin 85 is inserted is observed on the pellicle frame 87, and no contamination is observed. Then, the weight of the container body was 1.38 kg.

Comparative example 1

Similarly to the above embodiment, the pellicle assembly storing container body 91 having the shape shown in fig. 9 is manufactured by vacuum forming, and the fixing plug 94 and the plug support portion 95 are attached to the container body 91. Thereafter, the container body 91 is cleaned with clean pure water in a clean room, and the pellicle unit 96 is actually placed on the pellicle unit mounting table 92 of the prepared container body 91 and fixed by the fixing pins 94.

In the same manner as in the above-described example, the container main body 91 was left standing horizontally, and then 1 corner of the container main body was slightly lifted upward. As a result, the container body 91 meanders along the rib 93 as shown in fig. 6.

At this time, the pellicle 96 placed on the pellicle mounting table 92 was observed, and it was found that the same bending as the deformation of the container body occurred in the direction (diagonal direction), and that a part of the pellicle was wrinkled. Further, after the fixing pin 94 is pulled out from the jig hole of the protective film unit 96, it is found that a lot of foreign matters are adhered to the jig hole by strong friction of the pin, which can be immediately recognized even under a fluorescent lamp, and it is absolutely unacceptable for the requirement of maintaining the cleanliness.

Comparative example 2

In the above-described embodiment, the pellicle assembly storing container body 71 having the shape shown in fig. 7 was manufactured by vacuum forming in the same manner as in comparative example 1, and the fixing pins 72 and the pin supporting portions 73 were attached thereto.

In addition, 6000 for reinforcement is prepared by assembling aluminum alloy bar-shaped reinforcements 75 and 76 (40 mm in width × 5mm in thickness) outside the container main body 71 in a zigzag shape, and firmly connecting the plug support portion 73 made of ABS resin, the reinforcement holder 74, and the container main body 71 by bolts (not shown).

Thereafter, the container body is cleaned with clean pure water in a clean room, and the pellicle 77 is actually placed on the prepared container body and fixed with the fixing pin 72.

Then, as in the above-described example and comparative example 1, the pellicle assembly storing container body 71 was horizontally placed on the fixed tray, and 1 corner of the body was slightly lifted upward.

As a result, the container body is hardly distorted by torsion, and the carried pellicle is firmly fixed to the surface of the container body without any undesirable change.

Then, the fixing pin 72 was pulled out from the jig hole of the pellicle 77, and the periphery of the jig hole was observed by a halogen lamp in a dark room to find that the periphery was still clean.

However, the weight of the container body was 2.96kg, which is 2 times or more the weight as compared with the above examples.

Claims (3)

1. A protective film assembly container, comprising:

a container body for carrying the protective film assembly;

a cover body for covering the protective film assembly and engaging with the container body at the peripheral edge portion thereof,

it is characterized in that:

the container body is formed by molding a resin sheet, and the container body is provided with a plurality of ribs which cross a diagonal line of the container body outer shape, each rib does not intersect with other ribs of the plurality of ribs, and an included angle between each rib and the cross diagonal line is 30 degrees or more.

2. The protective film assembly receiving container of claim 1,

the ends of the ribs are connected to other ribs or a pedestal on which the pellicle is placed.

3. The pellicle assembly receiving container of claim 1 or 2, wherein,

in each of the rib portions, the height of the rib portion is not necessarily required, but has regions of different heights.