JPS6318734B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a dust-proof cassette for storing a photomask or reticle, which can be used in combination with a device for transporting a photomask or reticle for manufacturing semiconductor devices.

In recent years, in the manufacture of semiconductor devices, demands for reliability in mass production, etc. have been increasing. This requirement is particularly high for highly integrated devices such as LSIs. Generally, a reticle is used as a photomask to manufacture such LSIs. A circuit pattern is drawn on this photomask (hereinafter simply referred to as a mask) or reticle.

Usually, several types or more of these circuit patterns are required to make one LSI chip.

A mask or reticle is used for printing by being brought into close contact with the wafer to be printed in the contact method, or by overlapping it at a slight distance above the wafer in the proximity method. However, as mentioned earlier, manufacturing one LSI chip requires several types of circuit patterns, that is, multiple masks or reticles, which must be replaced every time exposure and printing are performed. Become. Devices that automatically convert masks or reticles in sequence in this manner, such as automatic mask conveyance devices, have been proposed.

In this device, a plurality of masks are stored in a cartridge, and the cartridge is moved up and down to select a mask with characteristics, take it out of the cartridge, and transport it to a predetermined position. Note that a similar device has been proposed for conveying a reticle.

However, if there is dust or scratches on the mask or reticle, it will naturally be printed as a pattern error in the circuit, which will not only reduce the reliability of the device but also, in the worst case, cause disconnections or short circuits in the circuit pattern. invite Therefore, if dust or scratches are found on the mask or reticle, immediately remove the mask or reticle and maintain it. Replace with the same type.) Work is required. However, with conventional conveyance devices, this work was all done manually.
In this way, it is not desirable for dust prevention to directly handle the mask or reticle manually. Furthermore, it is undesirable for the mask or reticle to be used as a holding member or the like when the mask or reticle is inserted into or removed from the cartridge, since it may cause scratches or dust.

The reason why it is necessary to take sufficient precautions against dust and scratches is that masks and reticles are expensive and it takes time to manufacture them. but,
In conventional devices, the mask and reticle are installed in the cartridge with them exposed, and this has the disadvantage that it is not easy to replace the mask or reticle in the cartridge, considering dirt and dust from the human body. Ta.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a cassette for storing a mask or reticle alone, which is kept in a substantially airtight state and protected from dust until the mask or reticle is transported to a predetermined position.

In order to achieve this object, the present invention is constructed as follows.

The mask has a box member that stores a reticle and has an opening that allows the mask or reticle to be inserted and removed approximately parallel to both surfaces of the box member, and a box member that has an opening that allows the mask or reticle to be inserted and removed approximately parallel to both surfaces of the box member. A holding member for holding a mask or a reticle, and an opening/closing member capable of closing an opening of the box member were provided so that predetermined gaps were formed on each surface.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view of a dustproof cassette according to an embodiment of the present invention. Usually, the size of a mask or reticle is standardized to specific dimensions. Further, the circuit pattern is drawn with a predetermined margin provided around the mask or reticle.

Now, a mask or reticle (hereinafter collectively referred to as a glass substrate) is housed in a dustpan-shaped bottom lid 3 in FIG. This bottom cover 3 is provided with a wall around the area other than the opening end surface 9 as shown in the figure. Two steps 3a and 3b are provided at the top of this wall. This stepped portion 3a holds the edge of the glass substrate. In addition, on the bottom cover 3, on the opposite side of the opening end surface 9,
A top cover 2 is attached by a hinge 7 and can be opened and closed as shown by arrow A in the figure.
Close the top side. Furthermore, the opening/closing member 1 is attached to the opening end surface 9 side of the upper lid 2 via a hinge 6 so as to be rotatable with respect to the upper lid 2 as shown by an arrow B in the figure.

Then, the upper lid 2 is rotated and fitted into the stepped portion 3b, and the opening/closing member 1 closes the open end surface 9, so that the glass substrate is stored in a substantially hermetically sealed state.

Further, a groove 8 is provided in the end face of the opening/closing member 1 as shown in the figure in order to operate in conjunction with a conveying device to be described later.

Additionally, projections 4, 5 are provided on the outer surface of the wall of the bottom lid 3 to hold the cassette in place. Regarding the function of these protrusions 4 and 5,
The details will be described later.

FIG. 2 is a partial perspective view of the cassette with the top lid 2 closed and the opening/closing member 1 opened. As described above, the upper lid 2 is placed on the stepped portion 3b, and the glass substrate (not shown) is placed on the stepped portion 3a. Since the opening/closing member 1 is provided so that it can be opened and closed by a hinge 6, a magnet 13 is embedded in the end of the opening end surface 9 of the bottom cover 3 as shown in FIG. 2 in order to prevent the opening/closing member 1 from being opened accidentally. I'll leave it there. If the opening/closing member 1 is made of synthetic resin, a magnetic material is fixed to the surface facing the magnet 13, which is the back surface of the opening/closing member 1 in FIG. In this embodiment, the back surface of the opening/closing member 1 and the opening end surface 9 need to be in close contact with each other, so the magnet 13, magnetic material, etc. are buried slightly below the surface in close contact with each other, and are not exposed on the surface. .

Figure 3 shows a glass substrate stored in a cassette.
FIG. 2 is a partial cross-sectional view of the cassette showing a state in which the upper lid 2 is closed. By placing the end portion of the glass substrate 10 on the step portion 3a, a predetermined space is formed on each of the upper and lower surfaces of the glass substrate 10. That is, the height of the step portion 3a and the step portion 3b is set to the height of the glass substrate 10.
By making the thickness larger than that, a predetermined gap can be formed between the top cover 2 and the glass substrate 10, and depending on the height from the bottom part 3c to the step part 3a of the bottom cover 3, the gap between the glass substrate 10 and the bottom part can be formed. A predetermined gap can be formed between 3c. In order to prevent the top cover 2 from opening accidentally, a magnet 12 is embedded at a predetermined position in the stepped portion 3b as shown in the figure. When the upper lid 2 is made of synthetic resin as described above, the magnetic material 11 is embedded in a position facing the magnet 12 and in close contact with the stepped portion 3b. A plurality of magnets 12 and magnetic bodies 11 are provided at predetermined positions on the step portion 3b.

To store a glass substrate in a cassette as described above, first open the top lid 2 as shown in FIG. 1, and place the glass substrate on the step 3a of the inner wall of the bottom lid 3.
Then, by closing the top lid 2 and closing the opening/closing member 1, the glass substrate is stored in a substantially hermetically sealed state. If this cassette is installed in a cartridge such as an automatic transport device as described above, the mask can be replaced with the entire cassette when changing the reticle, so there is less dust attached than directly replacing the mask or reticle. It has the advantage of being difficult.

Next, a description will be given of a device and its operation for taking out a mask or reticle from the cassette by combining this cassette with an automatic transport device or the like.

FIG. 4 is a perspective view showing the relationship between a cartridge section that holds a plurality of cassettes and a transport arm that takes out glass substrates. As shown in the figure, the aforementioned protrusions 4 and 5 fit into the grooves of the cartridges 14 and 15, and the plurality of cassettes are held in an overlapping manner. As mentioned above, since the projections 4 and 5 are provided at predetermined positions on the cassettes, all the cassettes are aligned when they are fitted into the grooves of the cartridges 14 and 15.

The transport arm 16 has a fork shape as shown in the figure, and the fork parts 16a and 16b are formed to be wider than the pattern drawing area on the glass substrate. The transfer arm 16 also has an air intake hole 1 for vacuum suction on the back side of the glass substrate.
7 is provided. Further, the transport arm 16 is moved by a drive device (not shown) in the stacking direction of the cassettes, that is, in the vertical direction (Z direction) and in the direction in which glass substrates are inserted and removed (X direction). Further, the end of the opening/closing member 1 of the cassette is provided with the groove 8 as described above, and the opening/closing pin 20 that engages with this groove 8 is provided.
An interlocking member 19 is provided. This interlocking member 19 is interlocked with the vertical movement of the transport arm 16.
Both are provided so as to be movable up and down (Z direction). Since the groove 8 is provided through the end of the opening/closing member 1 as shown in FIG. 2, the opening/closing pin 20 can be moved to any cassette in the state shown in FIG. 4.

Note that the Z-direction positions, that is, the heights, of the transport arm 16 and the opening/closing pin 20 are determined to be approximately equal. Further, the interlocking member 19 is provided so as to rotate as shown by an arrow, and this rotation is also controlled so as to be linked to the operation of a drive device (not shown).

Next, the operation of taking out the glass substrate stored in the cassette will be explained.

The transport arm 16 moves upward or downward to place a fourth cassette in front of a cassette containing a predetermined glass substrate.
When positioned as shown in the figure, the interlocking member 19 rotates approximately 90 degrees, and the opening/closing pin 20 opens the opening/closing member 1 of the cassette. As mentioned earlier, the heights of the transport arm 16 and the opening/closing pin 20 are determined to be approximately equal, and since they move in the Z direction at the same time, the opening/closing pin 20
Be sure to include the necessary cassette opening/closing member 1.
It engages with the groove 8 of. Then, with the opening/closing member 1 open, the transport arm 16 moves toward the cassette, and the fork portions 16a, 16b are inserted into the cassette. This situation is shown in FIG. FIG. 5 is a schematic view of the cassette containing the glass substrate 10, viewed from above, and the top lid 2, opening/closing member 1, etc. are omitted. As described above, the glass substrate 10 is held at the end by the step portion 3a. Also, the glass substrate 10
A circuit pattern 10a is drawn with a predetermined margin left around it. Therefore, the fork part 16
a and 16b are inserted so as to be able to contact the surface corresponding to this margin. Further, as is clear from FIG. 5, the fork portions 16a and 16b are inserted into the lower side of the glass substrate 10, that is, the space between the glass substrate 10 and the bottom portion 3c of the bottom cover 3 shown in FIG. . Therefore, the step portion 3a and bottom portion 3c shown in FIG.
The height of the surface of the fork portion 16 of the transfer arm 16 is
The thickness is set to be larger than the thickness of a and 16b. This is to prevent the fork parts 16a and 16b from rubbing the glass substrate 10 and the bottom cover 3 when inserted under the glass substrate 10. When the fork parts 16a and 16b are inserted into the cassette in this way up to the predetermined position,
Move the transport arm 16 upward. Then, the fork parts 16a and 16b come into contact with the blank space on the back surface of the glass substrate 10, and at this time, vacuum suction is also performed at the same time. The transport arm 16 further moves upward slightly and then stops. This operation is necessary to slightly lift the glass substrate 10 from the stepped portion 3a. Therefore, the glass substrate 10 shown in FIG.
The gap between the upper cover 2 and the upper cover 2 is determined at least according to the amount of lifting. The glass substrate 10 thus lifted is transported out of the cassette by moving the transport arm 16 in the direction of pulling it out of the cassette. And glass substrate 10
is sent to an exposure device for printing and an inspection device for masks and reticles. In this way, the glass substrate 10 that has been processed is put back into the cassette by a reverse operation to the previous take-out operation.

As described above, by creating a cassette in which a predetermined space is formed on the upper and lower surfaces of the glass substrate, the glass substrate can be slid and removed by the operation shown in the embodiment. can be prevented.

By the way, as mentioned earlier, in order to hold the cassette, the cartridge 14, which has grooves into which the protrusions 4 and 5 provided on the side surfaces of the cassette fit, is used.
15 is required. However, if the cartridges are in the form of pillars that are simply provided with grooves, when they are stacked as shown in FIG. 4, it is difficult to remove only a specific cassette from the cartridge. Therefore, in this embodiment, the cartridge 14 is divided into individual cassettes as shown in FIG. Each of the divided cartridges has a lock member composed of a hinge, a spring member, and the like. This situation is shown in FIG. FIG. 6 is a diagram simply showing how one cassette is attached to or removed from the cartridges 14, 15.

When the cassettes are piled up, plate members 14a and 15a on which the protrusions 4 and 5 of the cassettes are placed are placed between the cartridges 1 and 1 so that the cassettes do not come into contact with each other and maintain a certain distance as shown in FIG.
It is provided in grooves 4 and 15. Cartridge 1
4 is provided with a locking member 14C as shown in the figure. This lock member 14C is attached to the hinge 14b.
It is rotatable around , and is biased by a spring or the like (not shown) in the direction of the arrow. Therefore, as shown in FIG. 6, the locking member 14c is opened so that the protruding part 4 of the cassette is engaged with the groove of the cartridge 15, and the cassette body is rotated so that the engaged part is centered. For example, the cassette can be installed and removed individually. At this time, even if the opening/closing pin 20 is engaged with the groove 8 of the opening/closing member 1 of the cassette, since the cassette rotates around the engaging part of the cartridge 15 and the protrusion 4 as shown in the figure, this opening/closing pin 20 is also removed from the groove 8.

By storing the mask or reticle alone in the cassette as described above, it can be easily attached to or removed from the cartridge by hand. In other words, if a mask or reticle becomes unusable due to scratches, dust, etc., the entire cassette can be replaced on the spot, allowing you to work without touching the mask or reticle directly, which prevents dust from adhering to it. The effect of doing so is extremely large.

Although the cassette according to the embodiment of the present invention has been described above, such a cassette may be modified in various ways. For example, the step portions 3a on which the glass substrate shown in FIG. 1 is placed may be provided at the four corners of the bottom cover 3. In addition, in order to prevent the top lid 2 from opening accidentally, a pin is provided on a part of the opening end surface 9 of the bottom lid 3.
The opening/closing member 1 may be provided with a recess or a small hole into which the pin is inserted.

Furthermore, fork portions 16a and 16b of the transfer arm 16 take out glass substrates from this cassette.
A magnetic sensing element like a Hall element is installed at the tip of the
Furthermore, the cassette is provided with a magnet that biases the above-mentioned top lid 2 or opening/closing member 1 so as to generate lines of magnetic force also in the space between the step part 3a and the bottom part 3c, and the Hall element detects the lines of magnetic force. By doing,
It is also possible to perform precise positioning of the transport arm. Instead of a Hall element, for example, a reflective photoelectric detector is installed at the tip of the fork to detect the space below the glass substrate while controlling the transfer arm so that it does not come into contact with the glass substrate or the inside of the cassette. It can also be inserted and removed.

Furthermore, in order to open and close the opening/closing member 1 of the cassette in conjunction with the conveyance device, a groove 8 provided as an engaging portion in the end face of the opening/closing member 1 is shown in the embodiment. This can be varied depending on the transport device. For example, instead of a groove shape, it is possible to provide a protrusion that can engage with the opening/closing pin, or the end surface of the opening/closing member 1 itself can be extended beyond the outer shape of the bottom cover 3 of the cassette to form a protrusion. be. Furthermore, a magnetic material is fixed to this end face, and an electromagnet is provided at a position corresponding to the opening/closing pin 20 of the conveying device, and this electromagnet is excited to engage the opening/closing member 1 at the required position of the cassette. It may be made to match.

In addition, in the embodiment, the opening/closing member 1 is attached to the upper lid 2, but a mechanism for opening/closing the opening/closing member 1 (an engaging part provided on the end face of the opening/closing member 1, and an interlocking mechanism that engages with the engaging part) Depending on the operation of the members, etc.), the opening/closing member 1 may be attached to the bottom cover 3.

In the embodiment, the transport arm 16 is moved up and down, but it goes without saying that the cartridge holding the cassette can also be moved up and down.

As described above, by storing a mask or reticle in a cassette like the embodiment of the present invention, it is possible to prevent dust from the human body from adhering to it, and it is extremely easy to replace the mask or reticle. become. Furthermore, since the cassette is equipped with an opening/closing member at a position where the mask or reticle can be taken out almost horizontally, the cassettes can be stacked and used, making installation almost the same as conventional mask cartridge and reticle cartridges. It also has the advantage of taking up less space.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a dust-proof cassette showing an embodiment of the present invention, FIG. 2 is a partial perspective view of the cassette shown in FIG. 1, and FIG. 3 is a partial cross-section of the cassette shown in FIG. figure. Figure 4 is a perspective view showing the arrangement of the cartridge holding the cassette and the transport arm;
The figure is a plan view showing the arrangement of a mask or reticle and a transport arm inside a cassette. FIG. 6 is a plan view showing how the cassette is attached to the cartridge. [Explanation of symbols of main parts], 1...Opening/closing member,
2...Top lid, 3...Bottom cover, 3a, 3b...Stepped portion.

Claims (1)

[Scope of Claims] 1. A box member for storing a photomask or reticle for semiconductor device manufacturing, which has an opening at a position that allows the photomask or reticle to be inserted and removed approximately parallel to both surfaces of the box member; a member that holds the photomask or reticle so that a predetermined gap is formed between the inner surface of the box member and both surfaces; and an opening/closing member that can freely open and close the opening; A dustproof cassette that stores the photomask or reticle in a substantially hermetically sealed state. 2. The box member has a bottom lid provided with the holding member, and an upper lid that is pivotally supported by the bottom lid at a position opposite to the opening and that fits with the bottom lid,
The dust-proof cassette according to claim 1, wherein the opening/closing member is provided on the top lid or the bottom lid. 3 Claims characterized in that a first biasing member biasing the top lid and the bottom lid to a closed state and a second biasing member biasing the opening/closing member toward the opening are provided. The dustproof cassette described in item 2. 4. Claim 1, wherein the opening/closing member has an engaging portion on one end surface thereof for opening and closing the opening/closing member in conjunction with a conveyance device or the like.
The dustproof cassette described in item 1 or 3.