JPS61282229A - Dust-proof cassette - Google Patents

Abstract

PURPOSE:To protect the mask to be mounted on the under cover from adhesion of dust by reducing the contacting portion in the carrying section when carrying the under cover while separating from the upper cover in dust-proof cassette such as photo-mask to be employed in semiconductor manufacturing system. CONSTITUTION:Dust-proof cassette is comprising an under cover 10 for mounting a photo-mask and an upper cover 1 to be engaged with the under cover 10 thus to form an enclosed chamber. A guide groove 5 for enabling linear motion when separating the under cover 10 from the upper cover 1 is made in the side wall 4 of the upper cover 1. The guide pin 22 of the under cover 10 with fit loosely into said guide groove 5. Upon positioning of said guide pin 22 to the rearmost position of the guide groove 5, the upper cover 1 rotatable around said position is stopped against the under cover 10 by means of reverse L-type stopper member 3 integrally fixed to the upper cover 1 and a stopper projection 12 formed on the under cover 10. Consequently, the upper cover 1 and the under cover 10 can be enclosed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a dust-proof cassette, and particularly to a blood-proof cassette for a photomask or reticle conveniently used in semiconductor manufacturing equipment.

[Conventional technology]

One of the issues that must be solved in the manufacture of semiconductors such as ICs and LSI VLSIs is the problem of dust adhesion to masks or reticles. When an ultra-fine circuit pattern formed on a mask is transferred to a wafer, dust adhering to the mask may cause damage to the circuit pattern transferred to the wafer). In the worst case, the entire function of the semiconductor device is impaired.

However, in conventional semiconductor manufacturing equipment, since a worker must directly load a mask or reticle into a mask holder, there is a high possibility that dust from one's body will adhere to the mask or reticle. Furthermore, as the diameter of masks has increased in recent years, it has become difficult to handle them by hand.
〈Due to careless handling by the workers,
There is also a risk of damage due to scratches on the mask.

In order to solve the above-mentioned problems, operator intervention is avoided as much as possible when loading masks into semiconductor manufacturing equipment.

The development of automated equipment that can automatically transport and load masks or reticles is desired.

Here, when the dust-proof cassette is composed of an upper lid and a lower lid, and a mask or reticle is placed on the lower lid, and the lower IIi is separated from the upper lid and transported, dust will be generated if there are many contact parts in the transport direction. A dustproof cassette with fewer contact parts in the transport direction was desired.

[Problems to be solved by the invention and means for solving them]

The purpose of the present invention is to separate and transport the lower lid from the upper lid,
To provide a dustproof cassette which prevents dust from adhering to a plate-shaped body placed on a lower lid by reducing the number of contact parts in the transport direction.

Another object of the present invention is to provide a dustproof cassette with a high sealability by locking the lower lid and the upper lid.

A further object of the present invention is to provide a dustproof cassette suitable for automatically transporting a plate-like object in order to prevent dust from adhering to the plate-like object.

Its purpose is as a dustproof cassette.

and a lower lid for placing the plate-shaped object.

an upper lid that engages with the lower lid to form a sealed chamber;

a guide groove provided on a side wall of the upper lid for linear movement when separating the lower lid from the upper lid;

a guide pin that fits into the guide groove and is provided on a side wall of the lower lid;

In order to lock the upper lid, which is rotatable about the position when the guide pin is located at the innermost part of the guide groove, to the lower lid, the upper lid and the lower lid are provided with mutual locking parts. This is achieved by providing a locking means.

〔Example〕

Preferred embodiments of the present invention will now be described with reference to the attached nine drawings. FIG. 1 is a diagram showing the upper lid structure of the dustproof cassette of the present invention. The central part 2a of the front wall 2 of the top lid 1 protrudes from both ends 2b, while a flexible inverted-shaped locking member 3 is integrally attached to each of the retracted ends 2b.] It is attached. The holes 3b of the inverted locking member 3 are located at both ends 11 of the front wall 11 of the lower lid 10, which will be described later.
The upper lid 1 and the lower lid 10 are sufficiently sealed by the locking projections 12 and the locking member 3, which fit together with the locking projections 12 formed at the corresponding positions of b.

The surface of the central portion 2a of the front wall 2 of the upper lid 1 protrudes beyond the front surface 3 of the locking member 3 so that the locking member is not easily damaged even if the cigar dustproof cassette falls.

Next, to explain the side walls 4 of the upper lid 10, each side wall 4 has a first side wall portion 4a having the same (height) as the front wall 2, and the upper lid 1 and the lower lid 10 are overlapped. The second side wall portion 4b has a height that extends to the same position as the bottom portion of the lower lid 10 in the combined state.

The inner side of the second side wall portion 4b extends from the oblique side portion 4C in the horizontal direction (
A guide groove 5 extending in the conveying direction is formed. Note that the transport direction is the direction of the arrow in FIG. 2(A).

Here, the guide pin 22 of the lower lid 10 is loosely fitted into the guide groove 5.

The guide groove 5 may have a structure that does not penetrate the side wall 4b in the thickness direction as shown in FIGS. 1 and 2 (B), or it may penetrate the side wall 4b' as shown in FIG. 2 (C). It can also be used as a structure.

As a result, as shown in Fig. 2 (B) and (C), the lower cover 1
0 is restricted in its position in the horizontal plane by the upper lid 1 in the direction perpendicular to the conveying direction.

FIG. 3 shows that the upper cover 1 and the lower cover 10 are locked by the locking member 3.
Indicates the status of

Now, returning to FIG. 1, the protruding piece 6 provided at the lower end of the side wall portion 4b of the upper lid 1 is a holding member 44 of a carrier for storing cassettes in multiple stages, as shown in factor 141.
The guide pin 22 is held at the innermost part of the guide groove 5 and can swing about the position as a fulcrum.

As a result, when the locking members 3 and 12 are released, the guide pin 22 is located at the innermost part of the guide key 5, and the upper lid 1 is rotated about the position 22a at time t as a fulcrum, and the stopper is provided at a predetermined rotation angle position. The rotation stops and the slanted state is reached.

A step 8 is formed at the inner lower end of the rear wall 7 of the top cover 1, and the step 8 extends between the side walls 4.about.4 of the top cover 10. In a state where the upper lid 1 and the lower lid 10 are overlapped, the lower lid rear wall stepped portion 16, which will be described later, has a lower surface 16a that is similar to the upper lid 1.
It contacts and is supported by the upper surface 8a of the rear wall step portion 8.

FIG. 2(A) #i is a diagram showing the lower lid structure of the dustproof set of the present invention. Similar to the front wall part 2 of the upper lid 10, the central part of the front wall 11 of the lower lid 10 protrudes compared to both ends 11b, and the upper lid l is located at each retracted end part 11b.
An inverted-shaped locking member 3 attached to both m parts 2bK of the front wall of
A locking protrusion 12 that engages with is formed. Next, to explain the lower lid 100 side parts 13, the upper lid 1 and the lower lid 1
The lower surface 4 of the first side wall portion 4a of the upper lid 1 when
A protruding piece 14 extends from the upper end of the side wall 13 on which the holder d is placed. This protruding piece 14 has a length in the transport direction that is substantially equal to the length of the first side wall portion 4a of the upper lid 1 in order to seal the inside of the cassette when the upper lid 1 and the lower lid 10 are overlapped. is preferable.

The lower surface of this protruding piece 14 is placed by a fork portion in the case of automatic conveyance, which will be described later.

Note that guide pins 22 that are accommodated in guide grooves 5 formed in the second side wall portion 4b of the upper lid 1 are arranged adjacent to the protruding pieces 14 on both side walls 13.13 of the lower ★10.

At the lower end of the rear wall 15 of the lower lid 10, there is a stepped portion 16 having a shape corresponding to the stepped portion 8 formed at the inner lower end of the rear wall 7 of the upper lid.
is formed.

Further, an annular portion 18 is arranged near the center of the interior of the lower lid 10 and stands upright from the bottom portion 17 on which a mask or reticle is placed.

The annular portion 18 and the four walls 11a of the lower lid 10, 13°13.
15 is connected to the substantially central portion thereof by a lip 19 that is orthogonal to each other. In the circular mask 20Fi exposure device, the mask pattern surface faces downward.1 Normally, the mask is placed on the annular portion 18 with the patterned surface facing downward; It is preferable to make the height low so that it does not come into contact with the patterned surface of the mask 2o.

See you again! As shown in FIG. 2(A), protrusions 25 are arranged at equal intervals on the upper end surface of the annular portion 18, and the mask 20 is supported by the protrusions 25.

In addition, a pellicle film is removed from the patterned surface of the mask 20 to prevent dust from adhering to it.
In this state, the masking mask is placed on the annular portion 18 with the pattern side facing down. In this case the annular portion 18
The inner diameter of the pellicle membrane is larger than the outer diameter of the pellicle membrane, and the inner lip 19a must be made sufficiently low in consideration of the thickness of the pellicle membrane holding member.

Positioning pins 21 stand upright around the annular part 18 in a concentric circle centered on the orthogonal part 19b of the lip 19. When the mask 20 is placed on the annular part 18, the positioning pins 21 lower the position of the mask 2o. The height of the pin 21 is therefore lower than the annular portion 18, which helps to locate it approximately centrally within the lid 10.
Conveniently, it is set equal to or higher than the top surface position of the mask 20 placed on the surface.

Next, the principles of how to assemble and remove the upper lid 1 and lower lid 100 of the dustproof cassette of the present invention will be explained with reference to FIGS. 4 to 7. Please note that the explanation using the automatic conveyance system is
This is done in FIGS. 11 to 14.

With the mask 201 placed on the annular portion 18 of the lower lid 10 using the positioning pins 21 as a reference (FIG. 7), first insert the guide bins 22 and 22 extending from both side walls 13 of the lower lid into the first position of the upper lid 1. 2, toward the guide grooves 5, 5 formed in the side wall portions 4b, 4b.

Lower lid rear wall 15 to upper lid rear wall 7:! (Figure 6). When the guide bin 22.22 is accommodated in the guide 1115, 5 and the lower surface 16a of the step 16 of the lower cover 10 is in contact with and supported by the upper surface 8a of the rear wall step 8 of the upper tri (FIG. 5),
Guide bin 22. Rotate the top cover 1 counterclockwise as a 22ft shaft. As a result, the end of the inverted-shaped locking member 3 on the upper lid engages with the locking protrusion 12 on the lower lid, and the cassette is in the assembled state as shown in FIGS. 3 and 4.

To determine the number of upper and lower lids, the operations described above in steps 111 from FIG. 4 to FIG. 7 can be performed in reverse.

Next, an automatic conveyance system for automatically conveying masks will be explained.

In FIG. 8, the dustproof cassette 31 is the cassette carrier 3.
A fork unit 33 supported by an elevator unit 34, which is stacked on top of the cassettes 2 and 2 and moves vertically, automatically transports a predetermined dustproof cassette, and only the lower lid on which the mask is placed.

Note that the same vertical position of the fork unit 33 is precisely determined photoelectrically by a fixed index plate 35 and a photoswitch 36 provided on the elevator unit 34 as shown in FIG. 15(A)CB), as will be described later. Locking or unlocking of the upper cover and the lower cover by vertical movement of the fork unit 33 is made stable.

The lower lid of a predetermined dust-proof cassette extracted from the cassette carrier 32 is carried by an elevator unit 34 to an upper ask alignment stage 38, where the mask is sucked by a mask hand unit 37 and carried to an exposure stage.

FIG. 9 shows the flow of the mask described above.

In FIG. 9, 39 is a mask, 40 is a mask position detection unit, 41 is a mask loader, and 142 is an exposure position.

FIG. 10 is a diagram showing the appearance of the fork unit 33.

The seven oaks 33a and 33b have a slightly larger interval than both side walls 13 of the lower lid 10, and the lower surface of the protruding piece 14 of the lower lid 10 is placed thereon.

11 to 14 show automatic conveyance of a mask using the fork unit 33 described above.

FIG. 11 shows a state in which the fork unit 33 has been moved horizontally so as to approach a predetermined dustproof cassette.

At this time, regarding the dust-proof cassette/soto, the protruding piece 6 of the upper lid 1 is held by the holding member 44 of the carrier, and the upper lid 1 and the lower lid 10 are integrated by the locking members 3 and 12, so the dust-proof cassette is integrated. It is supported and fixed by a carrier.

Note that the protruding piece 14 on the lower cover is the guide bearing 4 for the carrier.
3.

Next, FIG. 12 shows that the fork unit 33 is shifted upward by several 11 L by the elevator unit 34 (the fork unit 33 supports the lower surface of the protruding piece 14 of the lower cover 10, and the bearing 46 in the 7 oak unit 33 A state in which the locking members 3 and 12 are released is shown.

The upper lid 1 rotates clockwise about the fulcrum 22a by the biasing force of the spring 45, and its position in the rotational direction is regulated by a stopper (not shown), so that the upper lid 1 stops in an obliquely raised state as shown in the figure.

Note that the fulcrum 22a is the position when the guide bin 22 is at the innermost part of the guide groove 5.

! Fig. 13 shows a state in which the fork unit 33 is placed on the lower cover 10 (i-) and retreats in the horizontal direction, that is, when the lower cover 1° is pulled out.The vertical position of the fork unit 33 in Fig. 13 is shown in Fig. 12. In addition, the position of the lower lid 10 in the transport direction is regulated on the fork unit 33.

FIG. 14 shows a state in which the fork unit 33 has reached the retracted position.

After this, the lower lid 10 is brought to the uppermost position by the elevator unit 34, and the mask reaches under the mask grip unit 37.

The above is the order in which the mask is removed by the automatic transport system, but when the mask is inserted into the dustproof cassette, the flow described above is reversed. That is, the mask is placed on the lower lid 10 and moved by the fork unit 33 to approach the dustproof cassette, so that the guide bin 22 of the lower lid 100 reaches the innermost part of the guide groove 5 of the upper lid 1.

Then, when the fork unit 33 is shifted downward, the claw portion 47 of the fork shifter 33 pushes down the locking member 3, so the upper lid 1 rotates counterclockwise around the fulcrum 22a, and the locking member 3 of the upper lid 1 engages with the protrusion 12 of the lower lid 10,
The upper lid 1 and the lower lid 10 are integrated.

The fork unit 33 then retreats horizontally from the downwardly shifted position.

Here, detection of the vertical position of the fork using the index plate 35 and the photoswitch 36 is shown in FIGS. 15(A) and 15(B).

Four 7-way switches 361L to 36d are provided in the elevator unit 34 with respect to the fixed index plate 35.

! In Figure 15 (A), 7 Otosui/f 3 +61L'
~36dl is fork unit 3 to close the upper lid l.
3 indicates a position shifted downward by Δ.

FIG. 15(B) is a view taken in the direction perpendicular to the paper surface of FIG. 15(A), and shows a state in which, for example, in a photo switch 360, the light from the light emitting part 36p is blocked by the index plate 35 and does not reach the light receiving part 36qK, so there is no output. It shows.

It is detected at the lower position in the vertical direction of the fork unit 33 (see Figure 11) Ifi7 # switch 36 b' and 36 (''), while the higher position in the vertical direction of the fork unit 33 (see Figures 12 to 14) is photo switch 3
Detected at 6& and 36d.

In the figure, L-it indicates the light shielding part of the index plate 35,
J
)-C1, +l*) correspond to the intervals between the cassette storage positions of the cassette carrier 32.

Now, various modifications can be made to the embodiments described above.

For example, in W, 3, the front wall 2 of the upper lid 1 and the front wall 1 of the lower lid 10
Although the contact surface of No. 1 is flat, it may have a stepped shape as shown in FIGS. 4 to 7. In addition, the rear wall of the top lid 1 is the first
As shown in Figures 1 to 14, the DJ3
You can make a dent as you like. This makes it easy to manually set the dustproof cassette in the cassette carrier.

Furthermore, when the upper and lower lids are overlapped and the mask is stored in the cassette, a mask misalignment prevention pad 24 ( (Fig. 7) may be provided.

In addition, the material of the upper cover, lower cover, and cover of the set is PEEK (Poly Ether Ether Ke
bone) Toy resin is preferred. This is because in the event that dirt, oil, etc. adhere to the cassette, the cassette will be cleaned, but PEEK will not be damaged by cleaning solutions of various sizes, and it also has excellent mechanical strength.

In the above embodiments, the mask is circular, but it goes without saying that it may be square.

〔Effect of the invention〕

According to the first aspect of the present invention, there is provided a dust-proof cassette that reduces the number of contact parts in the transport direction when the lower lid is separated from the upper lid and is transported to prevent dust from adhering to the plate-shaped body placed on the lower lid. Can be provided.

Further, by locking the lower lid and the upper lid, it is possible to provide a highly airtight dustproof cassette.

Furthermore, it is possible to provide a dustproof cassette suitable for automatically transporting a plate-like object in order to prevent dust from adhering to the plate-like object.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of the upper lid structure of the dustproof cassette of the present invention. FIG. 2(A) is a perspective view of the lower lid structure of the dust-proof cassette of the present invention, and FIG. 2(B) and (C) are cross-sectional views of the dust-proof cassette viewed from the transport direction. FIG. 3 is a diagram showing the dustproof cassette of the present invention in a combined state. FIG. 4 to FIG. 7 are explanatory diagrams of the principle in the case where the upper cover and lower cover of the dustproof cassette of the present invention are separated and the plate-shaped body placed on the lower cover is transported. FIG. 8 is a schematic diagram of the automatic conveyance system. FIG. 9 is a diagram showing the movement (flow) of a plate-like object by the automatic conveyance system. FIG. 10 is a diagram showing the fork section of the automatic conveyance system. FIGS. 11 to 814 are explanatory diagrams in the case where the upper lid and Tl of the dustproof cassette are separated and the plate-shaped body placed on the lower lid is automatically transported using an automatic transport system. FIGS. 15(A) and 15(B) are explanatory diagrams for detecting the vertical position of the fork using an index plate and a photoswitch. In the figure, 1 is the top cover, 3 is the locking member, 5 is the guide groove, and 6.13 is the protruding piece. 10 is a lower lid, 12 is a locking protrusion. 22 is a guide bottle. 33 is the fork unit. 44 is a carrier holding member. Patent Appearance Person Canon Co., Ltd. Figure 2 (8) A-Figure 2 ζC) Ari

Claims (1)

[Claims] 1. A lower lid (10) for placing a plate-shaped object, an upper lid (1) for engaging with the lower lid to form a sealed chamber, and a lower lid (1) provided on a side wall of the upper lid. a guide groove (5) for linear movement when separating the lower cover from the upper cover; a guide pin (22) fitted in the guide groove and provided on the side wall of the lower cover; In order to lock the upper cover, which is rotatable about the innermost position of the guide groove, to the lower cover, the upper cover and the lower cover are provided with mutual locking parts (3). , 12). 2. The upper lid has a pad (
24) The dustproof cassette according to claim 1, wherein: 3. The dustproof cassette according to claim 1, wherein the locking portion of the upper lid is shorter than the front wall of the upper lid. 4. The dustproof cassette according to claim 1, wherein the position of the lower lid in a direction perpendicular to the conveyance direction within the conveyance plane is regulated by the guide pin. 5. The lower lid has a positioning pin (2) for positioning the plate-shaped body.
1) The dustproof cassette according to claim 1. 6. The dustproof cassette according to claim 1, wherein the lower lid is provided with an annular placing part (18) on which a part of the plate-like body is placed. 7. Claim 6, further comprising a plurality of protrusions (25) for partially placing the plate-like body on the annular placing part.
Dustproof cassette as described in section. 8. The dustproof cassette according to claim 1, wherein the front wall or the rear wall of the upper cover and the lower cover have a stepped structure to improve sealing performance.