JPS6319859B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a dustproof cassette, and more particularly to a dustproof cassette for a photomask or reticle conveniently used in semiconductor manufacturing equipment.

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 transferring ultra-fine circuit patterns formed on a mask onto a wafer, if there is dust attached to the mask, the circuit pattern transferred onto the wafer may be damaged, resulting in damage to semiconductors such as LSIs that are manufactured into products through post-processing. This not only reduces the performance of the device, but in the worst case, the entire function of the semiconductor device is impaired.

However, in conventional semiconductor manufacturing equipment, a worker must manually load a mask or reticle into a mask holder, so there is a high possibility that dust from the human body will adhere to the mask or reticle. Furthermore, as masks have become larger in diameter in recent years, they have become difficult to handle by hand, and there is a risk of scratches or damage to the masks due to careless handling by workers.

In order to solve the above-mentioned problems, it has been desired to develop automated equipment that can automatically transport and load masks or reticles while avoiding operator intervention as much as possible when loading masks into semiconductor manufacturing equipment.

An object of the present invention is to provide a mask (or reticle) dustproof cassette with a sealed structure that is effective in preventing dust from adhering during storage.

Another object of the invention is to provide a mask (or reticle)
An object of the present invention is to provide a dustproof mask cassette having a structure suitable for automatically conveying masks.

According to the present invention, by storing the mask or reticle in a cassette and carrying it, handling becomes easy and dustproof effects can also be obtained. In addition, the cassette shape has been devised, making it possible to automate the transportation of masks, eliminating the need for worker intervention.
This also prevents dust from adhering to the mask.

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a diagram showing the upper lid structure of the dustproof cassette of the present invention. A central portion 2a of the front wall 2 of the upper lid 1 protrudes compared to both ends 2b, and an inverted L-shaped locking member 3 is integrally attached to each of the retracted ends 2b. This inverted L-shaped locking member 3 has a sufficient length and length so that its ends fit into locking protrusions 12 formed at corresponding positions on both ends 11b of the front wall 11 of the lower lid 10, which will be described later. It must be flexible.

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

A guide groove 5 extending horizontally from the oblique side portion 4c is formed in the second side wall portion 4b. If this guide groove 5 has a depth sufficient to partially accommodate the guide pin 22 of the lower lid 10, the second
It may have a structure in which it extends halfway in the thickness direction of the side wall portion 4b, or it may have a structure in which it penetrates through the second side wall portion 4b. Furthermore, the second side wall portion 4b
A protruding piece 6 is integrally formed at the lower end of each of the mask cassettes, into which carriers for stacking and storing mask cassettes in a plurality of stages are fitted, and which is useful for positioning the top cover between the carriers.

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

FIG. 2 is a diagram showing the lower lid structure of the dustproof cassette of the present invention. Similarly to the front wall 2 of the upper lid 1, the lower lid 1
The central part of the front wall 11 of the cover 1 protrudes from both ends 11b, and the retracted ends 11b each have an inverted L that is attached to both ends 2b of the front wall of the top cover 1.
A locking protrusion 12 that engages with the letter-shaped locking member 3 is formed. Next, the side walls 13 of the lower lid 10 will be described. When the upper lid 1 and the lower lid 10 are overlapped, the protruding pieces 14 on which the lower surface 4a of the first side wall portion 4a of the upper lid 1 is placed are located on the side walls 13. Extending from the top end. This protruding piece 14 is connected to the upper lid 1 and the lower lid 10.
In order to seal the inside of the cassette when these are overlapped, it is preferable that the length is substantially equal to the length of the first side wall portion 4a of the upper lid 1. Also, the protrusion 14, like the protrusion 6 of the top cover 1, must be wide enough to fit into the carrier and assist in positioning the bottom cover 10 within the carrier. Furthermore, on both side walls 13, 13 of the lower lid 10,
A guide groove 5 formed in the second side wall portion 4b of the upper lid 1
A guide pin 22 housed in the guide pin 22 is arranged adjacent to the protruding piece 14 .

A step 16 is formed at the lower end of the rear wall 15 of the lower lid 10 and has a shape corresponding to the step 8 formed at the inner lower end of the rear wall 7 of the upper lid. This step 16
In this case, the lower surface 16a is the upper surface 8a of the rear wall stepped portion 8 of the upper lid 1.
Unlike the case of the top cover, it extends through both side walls 13, 13 because it is in contact with and is supported by the top cover.

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, 1 of the lower lid 10
Rib 1 that is perpendicular to the approximately central portions of 3, 13, and 15.
connected by 9. Since the mask 20 is normally placed on the annular portion 18 with the patterned surface facing downward, the ribs 19a inside the annular portion 18
It is preferable that the height is low so that it does not come into contact with the patterned surface of the mask 20. Further, as shown in FIG. 2, projections 25 may be arranged at equal intervals on the upper end surface of the annular portion 18, and the mask 20 may be supported by the projections 25.

In addition, a pellicle film is often attached to the patterned surface of the mask 20 to prevent dust from adhering to it. Place it. In this case, the inner diameter of the annular portion 18 must be larger than the outer diameter of the pellicle membrane, and the inner rib 19a must be made sufficiently low in consideration of the thickness of the pellicle membrane.

Around the annular portion 18, there is a perpendicular portion 19b of the rib 19.
Positioning pins 21 stand upright in a concentric circle with the center as the center. This positioning pin 21 serves to position the mask 20 approximately at the center within the lower lid 10 when the mask 20 is placed on the annular portion 18 . For this reason, it is convenient that the height of the pin 21 is set equal to or higher than the upper surface position of the mask 20 placed on the annular portion 18.

Next, the upper lid 1 and the lower lid 10 of the dustproof cassette of the present invention
How to assemble and remove them will be explained with reference to FIGS. 4 to 7.

A state in which the mask 20 is placed on the annular portion 18 of the lower lid 10 with reference to the positioning pins 21 (Fig. 7)
First, remove the guide pins 2 extending from both side walls 13 of the lower cover.
2, 22 toward the guide grooves 5, 5 formed in the second side walls 4b, 4b of the upper lid 1, the rear wall 15 of the lower lid is brought closer to the rear wall 7 of the upper lid (6th
figure). When the guide pins 22, 22 are accommodated in the guide grooves 5, 5, and the lower surface 16a of the stepped portion 16 of the lower lid 10 contacts and is supported by the upper surface 8a of the rear wall stepped portion 8 of the upper lid 1 (FIG. 5), The upper cover 1 is rotated around the guide pins 22, 22.
Or rotate the lower lid 10. As a result, the upper lid is inverted L.
The ends of the letter-shaped locking members 3 engage with the locking protrusions 12 on the lower lid, and the cassette is in the assembled state as shown in FIGS. 3 and 4. To remove the upper cover and lower cover, the above-described operations may be performed in reverse order in the order shown in FIGS. 4 to 7.

In FIGS. 1 and 2, the contact surfaces of the front wall 2 of the upper lid 1 and the front lid 11 of the lower lid 10 are shown as flat surfaces.

According to the present invention, in order to increase the sealing force of the dust-proof cassette, the abutting portions of the front walls 2 and 11 are arranged as shown in FIGS.
Complementary shapes as shown can also be used.
Furthermore, when the mask is stored in the cassette with the upper and lower covers overlapped, a mask displacement prevention pad 24 (No. 7 figure)
may be provided.

Although the cassette of the present invention has a sealed structure that prevents dust from adhering to the mask housed inside, it also effectively prevents dust from coming from the cassette itself due to rubbing of the upper and lower lids of the cassette, etc.
It is preferable to use resin such as PEEK (Poly Ether Ether Ketone). PEEK is resistant to being damaged by various types of cleaning fluids that are used to clean the cassette in the event that dirt, oil, etc. adhere to it, and it also has excellent mechanical strength.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of the upper lid structure of the dust-proof cassette of the present invention, FIG. 2 is a perspective view of the lower lid structure of the dust-proof cassette of the present invention, and FIG. 3 is a diagram showing the dust-proof cassette of the present invention in a combined state. , 4 to 7 are views for explaining the combination and removal of the upper and lower lids of the dustproof cassette of the present invention, respectively. 1... Top lid, 2... Front wall, 3... Locking member, 4
... Side wall, 5 ... Guide groove, 8 ... Step section, 10 ...
Lower lid, 14... protruding piece, 22... guide piece.

Claims (1)

[Claims] 1. Consisting of an upper lid and a lower lid, the upper lid includes a guide groove formed in opposing side walls, and a locking means for locking the front wall of the lower lid and the upper lid. It has a front wall and a rear wall that includes a portion that supports a portion of the rear wall of the lower lid, and the lower lid includes a guide pin that fits in the guide groove on the opposing side wall. A dustproof cassette. 2. The dustproof cassette according to claim 1, wherein the upper lid has protruding pieces on opposing side walls. 3. The dust-proof cassette according to claim 1, wherein the lower lid has protruding pieces on opposing side walls. 4. The dustproof cassette according to claim 1, wherein the lower lid includes a member for placing an object to be stored inside. 5. The dust-proof cassette according to claim 1, wherein the dust-proof cassette includes a member for preventing displacement of an object stored therein. 6. The dustproof cassette according to claim 1, characterized in that the dustproof cassette is manufactured from PEEK ( ). 7. The dust-proof cassette according to claim 1, wherein the contact portions of the front walls of the upper lid and the lower lid have complementary shapes.