JPH03782B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus 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 photomask or reticle is used to manufacture such LSIs and the like. 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 being placed over the wafer at a slight distance from 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. As described above, devices for automatically exchanging masks or reticles one after another, 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 specific mask, 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 a new one of 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. In addition, when putting a mask or reticle in and out of a cartridge for transportation, the mask or reticle may be used as a holding member, etc.
This is undesirable because it causes scratches and 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. However, in conventional devices, the mask and reticle are mounted inside the cartridge with them exposed, so it is not easy to replace the mask or reticle inside the cartridge for maintenance, considering the dirt and dust from the human body. It had the disadvantage of not having

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a mask or reticle conveying device that is kept in a substantially sealed state and dust-proof until the mask or reticle is conveyed to a predetermined position.

In order to achieve this object, the present invention is constructed as follows. In other words, there is a case body with an opening formed in the part where a substrate such as a photomask or reticle can be taken in and out horizontally, and one end of the opening of this case body that rotates vertically around an axis parallel to the surface of the substrate. A cassette case composed of a freely supported door member for closing an opening, etc. is provided, and a photomask and a reticle are stored in the cassette case in a substantially hermetically sealed state.

Here, a holding part is formed in the cassette case to hold the photomask or reticle so that it is housed with a predetermined gap between the upper and lower surfaces of the photomask and the inner wall of the cassette case. Further, an engaging portion (groove or protrusion) for engaging with the door opening/closing mechanism is formed at the end of the door member in the direction of the rotation axis. The plurality of cassette cases are then mounted on a cartridge that holds the cassette cases so that the door members are aligned and stacked.

Furthermore, in order to insert and remove the reticle through the opening of the cassette case, the required photomask has a thickness smaller than the gap on the bottom side of the photomask or reticle in the cassette case, a transport arm that horizontally enters the space without contacting the lower surface and the case body; and a transport arm that is coupled to the transport arm;
A horizontal carrying member receives a photomask or reticle from the holding part into the carrying arm by vertical relative displacement between the carrying arm and the holding part in the cassette case, and leaves the photomask or reticle horizontally through the opening. A horizontal guide member for guiding the horizontal movement of the member, a vertical moving means for relatively moving the horizontal guide member and the cartridge in the stacking direction of the cassette cases, and an opening/closing means for opening and closing the door member of the cassette case are provided. . This opening/closing means includes a support member that is adjacent to the engagement portion of the door member of the cassette case and is provided so that the vertical positional relationship is approximately constant with respect to the horizontal guide member, and a drive source that controls the support member. It is composed of a movable opening/closing member (opening/closing pin) that is movably provided with respect to the member. When the transport arm (or horizontal transport member) is at a height approximately equal to the lower surface of the desired cassette case and faces the door member, this movable opening/closing member opens the engaging portion of the door member. It is provided so as to face a portion of the door member remote from the rotation axis on the back side without contacting it, and to engage with this engaging portion by being biased by a drive source to press the door member from the back side.
As the moving means operates, the opening/closing means can move in a non-contact manner along the door members of the plurality of cassette cases, and the horizontal conveying member can move the cassette cases containing desired photomasks or reticles. When facing each other, the door member of the cassette case is opened and closed prior to the insertion/removal operation of the conveyance means.

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

FIG. 1 is a perspective view of a dust-proof cassette case (hereinafter simply referred to as a "cassette") that can be installed in a transport device 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. Further, an upper lid 2 is attached to the bottom lid 3 on the opposite side of the opening end surface 9 by a hinge 7 so that it can be opened and closed as shown by arrow A in the figure. The upper surface of the bottom cover 3 is closed by fitting into the stepped portion 3b of the bottom cover 3. Furthermore, the open end 9 of the upper lid 2
The door member 1 is attached to the side via the hinge 9 as indicated by the arrow B in the figure.
It is rotatably attached to the upper lid 2 as shown in FIG. The upper cover 2 rotates and fits into the stepped portion 3b,
By the door member 1 closing the opening end surface 9,
The glass substrate is stored in a substantially hermetically sealed state. Furthermore, a groove 8 is provided in the end face of the door member 1 as shown in the figure in order to interlock with a conveyance device to be described later. Furthermore, projections 4, 5 are provided on the outer surface of the wall of the bottom cover 3 for holding the cassette in a predetermined position on the transport device. The functions of the protrusions 4 and 5 will also be described in detail later.

FIG. 2 is a partial perspective view of the cassette showing a state in which the top cover 2 is closed and the door member 1 is opened. As described above, the upper lid 2 overlaps the stepped portion 3b, and the glass substrate (not shown) is placed on the stepped portion 3a.
Since the door 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 open end surface 9 of the bottom cover 3 as shown in FIG. 2 in order to prevent the door member 1 from being opened accidentally. I'll put it in there. If the door 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 door member 1 in FIG. In this embodiment, since the back surface of the door member 1 and the opening end surface 9 need to be in close contact with each other, the magnet 1
3. Magnetic materials, etc. are buried slightly below the surfaces that are in close contact with them, and their surfaces are not exposed.

In addition, in this embodiment, when forming the groove 8 at the side end of the door member 1, the protruding part (engaging part) 8a that defines the groove 8 is important, and the opening/closing pin of the opening/closing mechanism described later is important. Therefore, when opening the door member 1, an opening/closing pin as a movable opening/closing member comes into contact with the back side of the protruding portion 8a and presses the door member 1 from the back side. Furthermore, when the upper lid 2 and the lower lid 3 are closed, the opening end surface 9
An opening is formed only in the case, thereby forming the case body.

Figure 3 shows a glass substrate stored in a cassette.
FIG. 2 is a partial cross-sectional view 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, by making the height of the stepped portion 3a and the stepped portion 3b larger than the thickness of the glass substrate 10, the upper lid 2 and the glass substrate 10 are
A predetermined space can be formed between the bottom part 3c of the bottom cover 3.
Depending on the height from the step part 3a to the glass substrate 1
A predetermined space can be formed between the bottom part 3c and the bottom part 3c. Further, a magnet 12 is embedded in a predetermined position of the stepped portion 3b as shown in the figure to prevent the top cover 2 from being opened inadvertently. As described above, when the top cover 2 is made of synthetic resin, the magnetic body 11 is embedded in a position facing the magnet 12 that is in close contact with the stepped portion 3b. A plurality of these 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 cover 2 as shown in FIG. 1 and place the glass substrate on the step 3a of the inner wall of the bottom cover 3. Then, by closing the top lid 2 and closing the door member 1, the glass substrate is stored in a substantially airtight state. If this cassette is installed in a cartridge such as a transport device, when the mask or reticle is replaced due to dirt or dust, the entire cassette can be replaced, so that dust will not adhere to it rather than replacing the mask or reticle directly. It has the advantage of being difficult.

Next, a description will be given of an apparatus that mounts a plurality of cassettes, takes out glass substrates from the cassettes, and transports them.

FIG. 4 is a perspective view showing a cartridge section that holds a plurality of cassettes, a transport arm that takes out glass substrates, and a drive mechanism thereof.

A column 43 is provided in parallel on the fixed base 18 for fixing the cartridge 15 and a plurality of cartridges 14 in a line as shown in the figure. Each of the cartridges 14, 15 has grooves formed on opposite sides thereof, into which grooves the protrusions 4, 5 of the cassette as described above fit. As mentioned earlier, the protrusions 4 and 5 are provided at predetermined positions on the cassette, so that the protrusions 4 and 5 do not touch the cartridge 1.
When the cassettes are inserted into the grooves 4 and 15, all the cassettes are aligned. Although a plurality of cartridges 14 are provided depending on the thickness of each cassette,
The details will be described later.

The U-shaped vertically moving member 30 is attached to the side wall of the cartridge 15 so that it can freely move only up and down along a guide rail (not shown) provided in the height direction of the cartridge 15. A belt 34 is provided in the cartridge 15 via pulleys 32 and 33 on the back side of the groove in which the cassette is mounted. The pulley 32 is provided at the top of the cartridge 15, and the pulley 33 is provided at the bottom.
3 rotation is worm gear 36, worm wheel 3
This is done by the rotation of the motor 37 via the motor 5. The rotation of the pulley 33 causes the belt 34 to
is transmitted to the pulley 32 by. Incidentally, in order to prevent each pulley from slipping between the belt 34 and the belt 34, the inside of the belt 34 and the outer peripheral surface of the pulley are provided with projections and depressions that mesh with each other.

Further, the vertically moving member 30 has a belt 3 inside it.
4, and is moved up and down by the feed of the belt 34, that is, by the rotation of the motor 37.

A horizontal guide member 31 extending in a direction orthogonal to the height direction of the cartridge 15 is fixed to the vertically moving member 30. This horizontal guide member 3
1 is also provided with a U-shaped horizontal movement member 41, which is movable only horizontally along a guide rail (not shown) provided on the horizontal guide member 31.
Although not shown in FIG. 4, the horizontal guide member 3
A belt and a pulley are also provided on the inner side 31a of the vertically moving member 30, and the horizontally moving member 41 is moved as described above by a motor (not shown) attached to the vertically moving member 30.
move. A transport arm 16 on which a glass substrate is placed via a support member 42 is provided on the horizontal movement member 41 so as to face the cassette.
The transfer arm 16 has a fork shape as shown in FIG. 4, with fork portions 16a and 16b facing toward the cassette opening/closing member 1. Further, an intake hole 17 is provided above the fork parts 16a, 16b for sucking the back surface of the glass substrate with vacuum, and the interval between the fork parts 16a, 16b is wider than the pattern drawing area on the glass substrate. It is formed like this.

Note that the above-described vertical movement by the vertically moving member 30 will hereinafter be referred to as movement in the Z direction, and the horizontally moving member 4
Let the horizontal movement by 1 be the movement in the X direction.

By configuring as described above, the transport arm 16 can freely move in the Z direction and the X direction by controlling each motor.

There are two limit switches on the pulley 32 side and the pulley 33 side of the cartridge 15 to limit the movement of the vertically moving member 30, and on the horizontal guide member 3 side.
1 is also provided with two limit switches for limiting the movement of the horizontally moving member 41, respectively.

As mentioned above, a groove 8 is provided in the side surface of the door member 1 of each cassette. This groove 8 is
It engages with an opening/closing device for opening and closing the door member 1. This opening/closing device consists of an opening/closing mechanism section 26 shown in FIG. 4, and an air cylinder 27 that provides driving force for opening/closing. The opening/closing mechanism section 26 is attached to the vertical movement member 30 and moves together in the Z direction.

FIG. 5 is a partial sectional view of the opening/closing mechanism section 26 seen from the side. This figure shows the state in which the vertically moving member 30 is moved by the motor 37 to a predetermined position corresponding to an arbitrary cassette. Air cylinder 2
A slide member 24 having a U-shaped notch 24a at the bottom is fixed to the piston 25 of No. 7. A ball 22a formed at the tip of the lever 22, which is supported by the shaft 19, is fitted into the notch 24a. This shaft 19 is connected to the support member 23
It is rotatably provided around a straight line parallel to the center line of rotation of the hinge 6 of the door member 1 of the cassette. Furthermore, a lever 21 is fixed on the opposite side of the shaft 19, and an opening/closing pin 20 that can be engaged with the groove 8 of the cassette is provided at the tip of the lever 21. The length and diameter of the opening/closing pin 20 are determined so that it does not come into contact with the inside of the groove 8 when the door member 1 is closed as shown in the figure. The state of the lever 22, shaft 19, lever 21, etc. is as shown in the perspective view of FIG. 6, and when the lever 22 rotates clockwise about the shaft 19, the opening/closing pin 20 also rotates clockwise. Therefore, in FIG. 5, when the air cylinder 27 is activated and the slide member 24 is moved to the right from the position shown in the figure, the ball 22a moves to the right while remaining in the notch 24a, and the lever 22 is moved clockwise. As it rotates, the opening/closing pin 20 also rotates clockwise.

When the opening/closing pin 20 begins to rotate clockwise, its tip first presses the back surface (inner wall of the groove 8) of the protruding portion 8a of the door member 1, and then the door member is held on the hinge 6.
Rotate clockwise or outward around the center. As is clear from this, when opening the door member 1, the rotation center line (hinge 6) of the door member 1 is
Opening/closing pin 2 facing the back part away from
0 is placed.

Furthermore, since the vertical movement member 30 and the transport arm 16 always move in the Z direction, the difference between the height of the transport arm 16 from the fixed base 18 and the height of the shaft 19 from the fixed base 18 is always constant. It is. In the embodiment, although not shown, when the opening/closing pin 20 is engaged with the groove 8 as shown in FIG.
The fork portions 16a and 16b of the transfer arm 16 are arranged in advance so as to face the cassette, as shown in FIG. 3, between the glass substrate 10 and the bottom portion 3c of the bottom cover 3. Note that since the groove 8 is provided penetrating the end of the door member 1, the fifth
In the state shown, the opening/closing pin 20 can be moved to any cassette.

Then, when the air cylinder 27 is activated and the ball 22a moves to the right in FIG.
0 clockwise rotation, the door member 1 of the cassette
is opened to approximately 90° from the position shown in Figure 5.

When the opening/closing member 1 is opened as described above, the horizontal moving member 41 shown in FIG.
a and 16b are inserted into the cassette. As mentioned above, when the air cylinder 27 is operated to open the cassette door member 1, the fork portions 16a, 16
The height of b from the fixed base 18 is approximately at the center of the gap below the glass substrate of the cassette. Therefore, the fork parts 16a, 16b are
It is inserted into the space below the glass substrate in the cassette. This situation is shown in FIG. FIG. 7 is a schematic view of the cassette containing the glass substrate 10, viewed from above, and the top lid 2, door member 1, etc. are omitted. As described above, the glass substrate 10 is held at the end by the stepped portion 3a. Further, a circuit pattern 10a is drawn on the glass substrate 10, leaving a predetermined margin around the glass substrate 10. Therefore, the fork parts 16a, 16b
is inserted so that it can touch the surface corresponding to this margin. Further, as is clear from FIG. 7, the fork portions 16a and 16b are inserted into the lower side of the glass substrate 10, that is, into the space between the glass substrate 10 and the bottom portion 3c of the bottom cover 3 shown in FIG. Therefore, the height of the surfaces of the step portion 3a and bottom portion 3c shown in FIG.
The thickness is set to be larger than the thickness of b. This is because when the fork parts 16a and 16b are inserted under the glass substrate 10, the glass substrate 10
This is to prevent the bottom cover 3 from being rubbed.

When the fork portions 16a and 16b are inserted into the cassette to a predetermined position in this manner, the transport arm 16 is moved upward by the drive of the motor 37. Then, the fork parts 16a and 16b come into contact with the margin on the back surface of the glass substrate 10, but at this time,
At the same time, vacuum suction is also performed through the suction hole 17. 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 and upper lid 2 shown in FIG.
The space between them 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 from the cassette. After that, air cylinder 2 again
7 is activated to close the door member 1. The glass substrate 10 is then 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 stored in the cassette again by the reverse operation of the previous take-out operation.

As described above, the glass substrates can be slid by creating a cassette with a predetermined space formed on the top and bottom surfaces of the glass substrates and by carrying out the transport operation as shown in the example. This will prevent you from competing.

Note that the transport arm 16 as shown in FIG.
It only moves in the direction and Z direction. Therefore, the glass substrate can only be transported up and down after being removed from the cassette. Therefore, in order to transport the glass substrate to an exposure device or an inspection device, it is usually necessary to move the glass substrate in directions orthogonal to each of the Z direction and the X direction. This orthogonal direction is defined as the Y direction, and the conveyance device is defined as a loader mechanism. The loader mechanism, which will be described in detail later, is provided at the top of the device shown in FIG. 4.

As mentioned above, when the vertically moving member 30 moves up and down and stops at an arbitrary cassette position, the door member 1 of the cassette is opened by the opening/closing pin 20, and then the fork portion 16a of the transfer arm 16 is opened. ，
16b is inserted into the cassette. At this time, it is sufficient that the fork parts 16a and 6b are inserted into the space below the glass substrate in the cassette without sliding. It is also conceivable that the fork parts 16a, 16b slide on the back surface of the glass substrate when inserted due to the error in amount. Therefore, in the device of the embodiment, the fork portions 16a, 16
A mechanism for detecting the height of the transport arm relative to the glass substrate is provided so that the transfer arm b is reliably inserted into the space below the glass substrate without sliding.

This detection mechanism will be explained with reference to FIG. 8th
The figure is a partial sectional view showing the relationship between the transport arm 16 and the position of the cassette. Although the door member 1 provided on the top cover 2 of the cassette is in an open state, it is omitted in the figure. When the horizontal movement member 41 moves toward the cassette as described above, the transfer arm 16
It is moved by the support member 42 to a position as shown in FIG. That is, the tip of the fork portion 16b moves to a position slightly inserted beyond the opening end surface 9 of the cassette and then stops.

The transport arm 16 is attached to the support member 42 via a hinge 51, and is rotatably provided around the hinge 51. The stopper member 52 also functions to prevent the transport arm 16 from rotating clockwise from the position shown in the figure, and to determine the horizontality of the transport arm 16 so that it is approximately parallel to the glass substrate in the cassette. do. In the state shown in FIG. 8, the transport arm 16 is in contact with the stopper member 52 due to its own weight. Further, the limit switch 50 detects the rotation of the transport arm 16 in the counterclockwise direction.

As mentioned above, the tip of the fork portion 16a is slightly inserted into the cassette and then stopped, but the amount of insertion of this tip is shorter than the length from the side end surface of the glass substrate 10 to the opening end surface 9. is desirable. If you do this, the transfer arm 16
The positioning of the upper cover 2 of the cassette during vertical movement is
It suffices if it is between the inner surface of the and the bottom part 3c of the bottom cover 3,
Positioning accuracy is no longer required.

Next, the operation of determining the correct position (between the glass substrate 10 and the bottom part 3c) from the state shown in FIG. 8 will be explained. In this state, first of all, the vertically moving member 30 is slightly moved downward. Then, the support member 42 also moves downward, but at this time, the tip of the fork portion 16b is attracted to the bottom portion 3c of the cassette. When the support member 42 is further moved downward, the transfer arm 16 is separated from the stopper member 52, the limit switch 50 is opened or closed, and the transfer arm 16 is slightly rotated counterclockwise as shown by the arrow in the figure. To detect. This detection is performed by a detection circuit (not shown) that detects a change in the state of the limit switch 50. Next, the downward movement of the transport arm 16 is stopped in accordance with the output of this detection circuit. The state at this time is shown in FIG. As shown, the fork 16b is slightly tilted as it approaches the bottom 3c of the cassette. The amount of inclination at this time is
It is always set to a constant value depending on the mounting position. Therefore, the height difference h between the tip of the stopper member 52 and the bottom 3c of the cassette is always a predetermined value. That is, the limit switch 50 is
This difference h is detected to stop the downward movement of the transport arm 16. When the difference h is detected in this way, the transport arm 16 moves upward.
This amount of movement is a predetermined amount. That is, as shown in FIG.
d, the thickness of the glass substrate 10 and the bottom part 3c
Let t be the interval between t>
d, the amount of upward movement of the transport arm 16 from the position shown in FIG. 9 is approximately h+(t-d)/2.
If so, the fork portions 16b, (16a) will be located approximately at the center of the space between the glass substrate 10 and the bottom portion 3c. In the above equation, the difference h, the thickness d, and the interval t are all predetermined constant values. Therefore, from the state shown in FIG. 9, the fork portion 16b (16
In order to accurately determine the height relative to the cassette in a), it is sufficient to move the transport arm 16 upward by a fixed amount according to the above formula.

In this way, once the height of the transport arm 16 is determined,
After that, as described above, attach the fork parts 16a and 16b.
The glass substrate 10 is inserted into the cassette and the glass substrate 10 is taken out. Note that the opening end surface 9 side of the bottom portion 3c serves to define a reference position spaced apart from the back surface of the glass substrate by a distance t for this positioning.

By the way, as mentioned above, 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 with only grooves provided, when they are stacked as shown in FIG. 4, it is difficult to remove 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. 10 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.
A plurality of grooves are provided at regular intervals in grooves 4 and 15. The cartridge 14 is provided with a locking member 14c as shown in the figure. This lock member 14c
is rotatable around the hinge 14b and is biased in the direction of the arrow by a spring or the like (not shown). Therefore, as shown in FIG. 10, if 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. , 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 door member 1 of the cassette, the cassette is not inserted into the cartridge 1 as shown in the figure.
5 and the protruding part 4,
This opening/closing pin 20 also comes off 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 converted on the spot, making it possible to work without touching the adhesive mask or reticle as in the past. The effect of preventing dust adhesion is extremely large.

Next, the loader mechanism described above will be described. FIG. 11 is a perspective view of a loader mechanism located above the apparatus shown in FIG. 4.

As mentioned above, the transport arm 16 carries the glass substrate 1
0 is loaded and taken out of the cassette by driving the horizontal moving member 41. Thereafter, the opening/closing mechanism section 26 operates to close the door member 1. FIG. 4 shows the state at that time. The loader mechanism includes a loader guide member 60 arranged to connect the upper part of the cartridge 15 and the support column 43, and a loader that is movable along a guide rail (not shown) provided in the longitudinal direction of the loader guide member 60. Part 6
1, a loader section 62 located above the transport arm 16 on the distal end side of the loader moving member 61, and the like. Inside 60a of the loader guide member 60, a drive system similar to the pulleys 32, 33 and belt 34 provided on the back side of the cartridge 15 described above is housed, and the belt is fed by a motor.
(Not shown) The loader moving member 61 is the loader guide member 6
0 via a U-shaped member 61a, and the member 61a is provided with a plurality of rollers so that it can move only in the direction of the arrow in FIG. 11 along the aforementioned guide rail (not shown). There is. Further, the loader section 62 is provided on the tip side of the loader moving member 61, and the loader section 62 has a box shape as shown in the figure.
The position thereof is arranged at a predetermined distance from the loader guide member 60. That is, the transport arm 16 is placed almost directly above the position where the glass substrate 10 is placed and taken out from the cassette.

A support plate 63 having a substantially similar shape to the glass substrate 10 is suspended inside the loader section 62 .
Four claw members 65a, 65b, 65c, and 6 are pivotably supported at positions corresponding to the four sides of the support plate 63 by shafts (not shown) parallel to each side.
5d are provided respectively. In addition, when simply using the claw member 65, the claw members 65a, 65b, 65
c, 65d shall be collectively referred to.

Further, the pistons of four air cylinders 67 are respectively engaged with the portions of the claw members 65 that protrude above the support plate 63, thereby causing the claw members 65 to swing. Furthermore, rollers 69 are rotatably provided at the portions of the claw members 65 that protrude below the support plate 63, respectively. This roller 69 is provided so that its rotation axis is parallel to each side of the support plate 63, as shown by the claw member 65a in the figure. The operation of the claw member 65 will be described in detail later, but since the circumferential surface of the roller 69 comes into contact with the glass substrate 10 when sandwiching it from four directions, the roller 69 does not damage the end surface of the glass substrate 10. It is made of synthetic resin such as

Note that the claw member 65 is constantly biased by a spring member (not shown) so that the roller 69 portion opens outward. Furthermore, the four air cylinders 67 are operated by air from a common air tube (not shown), and the air cylinders 67 are operated simultaneously. Furthermore, the claw members 65a, 65b are prevented from closing inward at the roller 69 portion by the operation of the air cylinder 67 by stoppers 66a, 66b. Note that the claws 65c and 65d are not subject to such restrictions.

Below the support plate 63 where the claws 65, air cylinders 67, etc. are provided, a suction plate 64, which is approximately the same size as the glass substrate 10, is suspended from the support plate 63 via a spring member (not shown). ing. Therefore, the suction plate 64 is provided so as to be elastically displaceable with respect to the support plate 63. The back surface of the suction plate 64 is provided with suction holes around the periphery for vacuum suction with which the top surface of the glass substrate 10 comes into contact. The position of the intake hole is
Although it was provided to be a blank area outside the pattern drawing area of the glass substrate 10, in the example, as shown in the figure,
Four intake pipes 68 corresponding to the positions of the intake holes pass through the support plate 63 and are fixed to the intake plate 64. The suction pipes 68 are connected to each other by pipes (not shown), and the vacuum suction operation of the glass substrate 10 is performed simultaneously.

Next, the glass substrate 10 placed on the transfer arm 16
The operation of transferring the data to the loader unit 62 is shown in FIGS.
This will be explained according to FIG. A transport arm 16 that takes out a desired glass substrate 10 from an arbitrary cassette.
moves a predetermined amount in the horizontal direction and stops at the position shown in FIG. At the same time, the opening/closing mechanism section 26 operates to close the door member 1 of the cassette. This predetermined amount of movement in the horizontal direction is such that the glass substrate 10 placed on the transport arm 16 is
It is set to be almost directly below.

After that, the transport arm 16 is raised. At this time, the transport arm 16 stops slightly below the suction plate 64, as shown in FIG. At this time, vacuum suction on the transfer arm 16 side is stopped. Next, as shown in FIG. 14, actuate the air cylinder 67 to
Close the roller 69 portion of No. 5 inward. Then,
The roller 69 comes into contact with the end surface of the glass substrate 10, but at the same time, the loader section 62 of the glass substrate 10
Perform positioning against. This positioning is determined by the aforementioned stoppers 66a and 66b. That is, even if the air cylinder 67 operates, the upper portions of the support plate 63 of the claw members 65a, 65b are locked by the stoppers 66a, 66b, so that
The roller 69 portions of the claw members 65a, 65b do not close inward beyond a predetermined amount. Therefore, the reference position of the glass substrate 10 is determined by the circumferential surface of the roller 69 provided on the claw members 65a, 65b. In addition, since the claw members 65a and 65b are respectively provided at mutually orthogonal peripheral portions of the support plate 63, the mutually orthogonal end face portions of the glass substrate 10 come into contact with the rollers 69 of the claw members 65a and 65b. Therefore, horizontal positioning of the glass substrate 10 becomes possible. Furthermore, claw members 65c and 65d
Since the roller 69 closes inward as far as the stroke of the piston of the air cylinder 67 allows,
The glass substrate 10 is urged by the rollers 69 of the claw members 65a, 65b and chucked. At this time, the abutment position between the roller 69 and the end surface of the glass substrate 10 is such that the shaft 69a of the roller 69 and the glass substrate 10 are approximately horizontal, as shown in FIG. Therefore, the claw 65 is attached to the glass substrate 1.
The length of the claw 65 below the support plate 63 may be determined so that the claw 65 will be in the state shown in FIG. 14 when held in the end face of the claw. Also, as shown in FIG. 11, the protrusion 70 below the roller 69 of the pawl 65
protrudes inside the circumferential surface of the roller 69 (on the glass substrate 10 side) as shown in FIG. This protrusion 7
0 is for preventing the glass substrate 10 from falling off when it comes out of contact with the roller 65.

When the positioning and chucking are completed in the above manner, the transport arm 16 is raised by the slight gap between the suction plate 64 and the glass substrate 10, as shown in FIG. At this time, glass substrate 1
0 comes into contact with the suction plate 64, but since the suction plate 63 is attached to the support plate 63 via the leaf spring 71 as described above, the suction plate 64 moves slightly upward, and the glass substrate 10 No large locking force is applied. In addition, as shown in FIG. 15, the roller 69
Since the roller 69 is chucking the end face of the glass substrate 10, the slight rise of the glass substrate 10 causes the roller 69 to rotate slightly. At the same time, vacuum suction is performed by the suction holes provided on the back surface of the suction plate 64, that is, the surface in contact with the glass substrate 10, as described above. Although the glass substrate 10 and the suction plate 64 are shown to be in close contact with each other in FIG. A portion is slightly raised and is in close contact with the glass substrate 10. Therefore, the suction plate 64 does not come into contact with the pattern drawing area.

Further, as mentioned earlier, the vertically moving member 30 that moves the transport arm 16 up and down is connected to the cartridge 15.
A limit switch 40 is provided at the top of the cartridge 15 to detect when the top of the cartridge has been reached. This limit switch 40 is shown in FIG.
With the arrangement shown in FIG. 11, it is provided to operate in the state shown in FIG. 15, that is, when the glass substrate 10 comes into contact with the suction plate 64 and further rises slightly. Therefore, the raising of the transport arm 16 may be stopped by operating the limit switch 40. Next, as shown in FIG. 16, the transport arm 16 is lowered by a certain amount and then stopped. This is to prevent the transport arm 16 from colliding with each other when the loader section 62 moves in a direction perpendicular to the plane of the paper in FIG.

As described above, the glass substrate 10 placed on the transport arm 16 is transferred to the loader section 62. When the delivery is completed, the loader section 62 moves in the direction of the arrow as shown in FIG. On the inside 60a of the loader guide member 60, there is a belt (not shown) driven by a motor, and the loader moving member 61
As the belt feeds, the burning device, dirt,
It is transported to an inspection device for defects, etc. Furthermore, the loader section 62
The transport arm 16 remains at the position shown in FIG. 17 until it moves and returns when the glass substrate 10 is chucked again.

As described above, the configuration of the conveyance device according to the embodiment of the present invention,
The motors for moving the transport arm 16 and the loader section 62 are preferably pulse motors in order to improve the accuracy of positioning and the like. Therefore, the motor 37 (shown in FIG. 4) that raises and lowers the transfer arm 16 is used as a Z motor, the motor that moves the transfer arm 16 horizontally as an X motor, and the motor that moves the loader section 62 as a Y motor. , the amount of rotation of each motor is controlled by the number of pulses. In addition, the operation of the limit switch 40 and the limit switch 50 which have been moved forward is detected, and the sequence of operation of each air cylinder, drive of the motor, etc. is determined according to a program on a small computer. Therefore, the simplest flowcharts of the main parts of this program are shown in FIGS. 18 and 19. FIG. 18 is a flowchart 200 when taking out a glass substrate from a cassette, and FIG. 19 is a flowchart 300 when storing a glass substrate into a cassette.

Therefore, let us consider a case where the transport arm 16 operates from a position as shown in FIG. In FIG. 18, the transport arm 16 performs an arm raising operation. That is, a pulse signal is applied from the computer to the Z motor to raise the transport arm 16. At this time, between the pulse and the pulse of the pulse signal, the arm 16
The calculator reads the state of the limit switch 40 that limits the upper limit of movement of the computer. Then, when the arm 16 rises the most and the limit switch 40 closes, the calculator stops outputting pulse signals to the Z motor. The vertical position of the arm 16 at this time is defined as the origin.

At this time, the counter in the calculator is reset. This counter is, for example, an up-down counter that counts the number of pulses of a pulse signal sent to the Z motor, and the number of pulses is a value proportional to the amount of rise and fall of the arm 16. Next, the calculator inputs from the input device the address of the cassette, that is, the number of the required cassette from the top of the stack of cassettes. This input device allows an operator to specify an arbitrary address, or to automatically specify addresses sequentially.

The calculator calculates the distance from the origin of arm 16 to its cassette according to this address. Then, a signal with the number of pulses based on the calculation result is applied to the Z motor. At this time, the Z motor is rotated in the opposite direction to that described above. The arm 16 thus descends and stops in front of a given cassette. Incidentally, the approximate value of this amount of descent L is calculated by the following formula.

L=l _c (n-1) + l _p n: address of the required cassette (from top to bottom,
n=1, 2...) l _c : Distance between cassettes l _p : Distance from the origin to the back surface of the glass substrate in the cassette at address 1 Therefore, the calculator applies only pulses proportional to the calculated value L to the Z motor. Output. This number of pulses and value L
The relationship is the rotation amount for one pulse of the motor,
This is a predetermined ratio based on the ratio of the worm gear and the foil.

When the arm 16 is positioned in front of a predetermined cassette in this manner, a cassette opening operation is performed to open the door member 1 of the cassette. In this operation, as described above, the air cylinder turns the door member 1 into the open state at about 90 degrees from the closed state.

Next, the arm 16 moves toward the cassette,
An arm positioning operation is performed to adjust the arm height to an appropriate amount as shown in FIGS. 8 and 9. At this time, the calculator outputs a predetermined number of pulses to the X motor to move the arm 16 to the position shown in FIG. Then, in order to lower the arm 16 slightly as described above, the calculator outputs a pulse signal in the direction of lowering the arm 16 to the Z motor and sequentially inputs the state of the limit switch 50. Then, at the moment when the state of the limit switch 50 changes (for example, from closed to open), the calculator stops outputting the pulse signal in the downward direction, and immediately after that, the arm 16 rises slightly, as described above. . This slight increase is approximately h+(t-
b) is a constant amount expressed as /2, and the calculator outputs a pulse signal to the Z motor in the direction in which the arm 16 rises. The number of pulses of the pulse signal is, of course, proportional to h+(t-d)/2.

The calculator then outputs a pulse signal to the X motor that causes arm 16 to move toward the cassette. The number of pulses at this time is also a predetermined constant number. Then, when the fork part of the arm 16 is located below the glass substrate, the calculator further moves the arm 16 to slightly lift the glass substrate.
Output a certain number of pulses to the Z motor.

Once the height of the arm 16 is determined in this way,
The calculator stores the count value of the aforementioned counter. Next, the calculator outputs a predetermined pulse signal to the X motor to move the arm 16 out of the cassette, and the glass substrate is removed. Further, after the cassette closing operation for closing the door member 1 of the cassette is performed, the computer closes the arm 16.
A pulse signal is output to the Z motor to raise the motor toward the origin again. The glass substrate taken out of the cassette in the above manner is transferred to the loader section 62 as described above. Furthermore, when the delivery is completed, the arm 16 is on standby in a slightly lowered position.

Next, referring to FIG. 19, the operation of storing a glass substrate in a cassette will be explained.

When the loader section 62 comes directly above the waiting arm 16, the calculator outputs a pulse signal to the Z motor to raise the arm 16. At this time, the calculator also inputs the state change of the limit switch 40 at the same time. Then, when the state of the limit switch 40 changes, the calculator stops outputting pulse signals to the Z motor and the counter is reset. Then, a receiving operation is performed in which the glass substrate is transferred from the loader section 62 to the arm 16. This is done by stopping the vacuum suction of the loader section 62, stopping the operation of the air cylinder, and opening the four claws.

When the receiving operation is completed, the arm 16 starts vacuum suction of the glass substrate. and arm 16
descends to the cassette from which the glass substrate is taken out. At this time, the calculator outputs a pulse signal for lowering the arm 16 to the Z motor, but at the same time, it compares the number of pulses of the pulse signal with the previously stored value proportional to the arm height. Then, when the two match, the output of the pulse signal is stopped. Thereafter, a cassette opening operation is performed to open the door member 1 of the cassette. Further, the calculator outputs a predetermined pulse signal to the X motor to move the arm 16 toward the cassette, and then outputs a pulse signal to the Z motor to lower the arm 16 slightly. In this way, the glass substrate is held by the step in the cassette, and the glass substrate is
6 is installed at an appropriate height determined by the arm positioning operation described above. Then arm 16
is pulled out of the cassette to complete the storage operation of the glass substrate, and then the cassette close operation is performed to complete the series of steps.

Although the embodiments of the present invention have been described above, various changes can be made to the positioning mechanism of the transport arm, the shape of the cassette, etc. Next, we will briefly discuss these changes.

In the embodiment, the transport arm is moved up and down to take out the required glass substrate from the cassette, but of course the cartridge with the cassette attached may be moved up and down. Further, although not directly related to the present invention, the conveyance device shown in the embodiment can be applied as is to a conventional cartridge that holds a plurality of glass substrates as is. At that time, as shown in FIG.
The stepped portions 101 and 102 provided on the inner wall of the glass substrate 10 are made to protrude slightly inward so that only the edge of the glass substrate 10 is placed thereon.
Make sure that you can enter the bottom side. Also, step part 1
The thickness of 01 and 102 is also made larger than the thickness of the transfer arm. Further, when the conveyance arm performs height positioning, projections 103 and 104 may be provided on the opening surfaces of the stepped portions 101 and 102 for pulling the tips of the fork portions to set the reference positions. In FIG. 20, protrusions 103 and 104 are provided at each step, although they are provided at only one step. Note that if the distance between the glass substrates is not so narrow and the thickness of the stepped portions 101 and 102 is considerably larger than the thickness of the transfer arm, only one of the protrusions 103 and 104 is sufficient.

Also, when positioning the height of the transfer arm,
Although the upward swing of the transport arm is detected by a limit switch, a vacuum detector (vacuum sensor) may also be used for this detection. In that case, as shown in FIG. 21, a small block 105 is provided where the limit switch was located, and the upper end surface 105a of the block 105 is brought into close contact with the back surface of the transfer arm 16. moreover,
An airtight chamber 105b is formed inside the block 105, and a tube 106 lowers the air pressure in the airtight chamber 105b. Then, the transfer arm 16 is connected to the shaft 51.
The upper end surface portion 10 of the block 105 swings around the
The moment the airtight chamber 105b leaves the airtight chamber 5a, the pressure in the airtight chamber 105b rises to almost atmospheric pressure. Therefore, by providing a vacuum sensor at the tip of the tube 106 and detecting this pressure change, it becomes possible to position the transfer arm. At this time, the transfer arm is vacuum-adsorbed to the block 105.
This also has the advantage of preventing the transport arm from swinging inadvertently.

Further, in the embodiment, the driving force for opening and closing the door member of the cassette is provided by an air cylinder, but a solenoid may also be used. Further, although the door member and the opening/closing pin are engaged by a groove, this may be formed by a protrusion other than the groove, for example, depending on the opening/closing mechanism. Furthermore, an electromagnet may be provided in place of the opening/closing pin, and a magnetic material may be provided at the end of the door member, and the electromagnet may be operated at the required cassette to attract the magnetic material to open the door member.

In addition, the timing for opening and closing the door member of the cassette is such that in the sequence explained in the example, the transport arm is raised or lowered in front of the required cassette, and then the transport arm is moved horizontally toward the cassette. It goes without saying that even during horizontal movement, the transfer arm can be opened and closed at a point where the tip of the fork portion slightly protrudes from inside the cassette.

As described above, according to the transport device according to the present invention, a substrate such as a mask or a reticle is stored alone in a cassette case in a closed state at all times.
Boards that are not needed are kept dust-proof.

In addition, when taking out a desired substrate, when the transfer arm connected to the horizontal transfer member reaches a height position approximately equal to the gap on the bottom surface of the substrate in the desired cassette case, the movable opening/closing member removes the cassette case. In addition, in order to select a desired cassette case, a horizontal conveyance member (horizontal guide member) and each cassette case are When the opening/closing movable member moves up and down relatively, the opening/closing movable member can move up and down relatively in a non-contact manner at a position facing the back side of the engaging portion of the door member.

Therefore, there is no need to separately provide movable opening/closing members in numbers corresponding to all of the plurality of cassette cases, resulting in an extremely compact design. Furthermore, since the movable opening/closing member and the door member of each cassette case move up and down relative to each other without contact, there is no dust generated by sliding, and multiple boards can be transported in an extremely clean environment. Can be done.

Note that when a substrate is taken out from inside a cassette case by a transfer arm connected to a horizontal transfer member, since a predetermined gap is formed on the upper and lower surfaces of the substrate, the sliding of the substrate and transfer arm inside the cassette case is prevented. Of course, this can prevent movement.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a dustproof cassette that can be attached to a transport device according to an embodiment of the present invention, Fig. 2 is an enlarged view of its main parts, and Fig. 3 shows a state in which glass substrates are stored in the cassette and the top cover is closed. FIG. 4 is a perspective view showing the transfer arm and its drive mechanism; FIG.
The figure is a partial cross-sectional view of the opening/closing mechanism, Figure 6 is an enlarged view of its main parts, Figure 7 is a plan view showing the fork section inserted under the glass substrate, and Figure 8 is a front view of the detection mechanism. , Fig. 9 is an explanatory diagram of its operation, Fig. 10 is an explanatory diagram of the lock member, Fig. 11 is a perspective view of the loader mechanism, and Figs. 12 to 16 are explanations of the operation of transferring the glass substrate to the loader section. It is a diagram. 17th
The figure is a perspective view showing the loader mechanism with a glass substrate loaded, Figure 18 is a flowchart when taking out a glass substrate from a cassette, Figure 19 is a flowchart when storing a glass substrate into a cassette, and Figure 20. 21 is a perspective view of a cartridge holding a plurality of glass substrates, and FIG. 21 is a diagram showing a transfer arm when a vacuum detector is used. [Explanation of symbols of main parts], Fig. 1, Fig. 20...cassette, 1... door member, 4, 5... protrusion, 14, 15... cartridge, 16... transfer arm, 26... Opening/closing mechanism section, 30... moving member.

Claims (1)

[Scope of Claims] 1. Case bodies 2 and 3 in which a substrate 10 such as a mask or reticle is stored substantially horizontally, and a substantially rectangular opening 9 is formed in a portion where the substrate is taken in and out parallel to the surface of the substrate. , a holding part 3a that is disposed around the inside of the case body and holds the peripheral portion of the board so that a predetermined space is created between the upper and lower surfaces of the board and the upper and lower inner wall surfaces of the case body; It has a size that closes the opening, and is rotatable about an axis 6 parallel to the substrate surface on an edge portion substantially parallel to the substrate surface among the edge portions defining the opening. It is a supported door member 1, and one side edge thereof partially protrudes in the direction of the axis 6, and
It has a plurality of cassette cases including a door member 1 in which an engaging part 8a having an abutting surface is formed on the back side facing the case bodies 2 and 3, and a plurality of cassette cases are housed in each of the cassette cases. In the conveying device for selectively taking out and conveying the substrates 10, the plurality of substrates are arranged so that when the door members 1 of each of the cassette cases close the opening 9, each door member is located in the same vertical plane. Cartridges 14 and 15 hold the cassette cases at approximately constant intervals in the vertical direction and are removably placed in the horizontal direction.
and has a thickness smaller than the space on the lower surface side of the substrate 10 in the cassette case, and when the door member 1 of the cassette case is open, the lower surface of the substrate and the case body are exposed through the opening 9. transport arms 16a and 16b that can horizontally enter the lower surface side space without contacting any of the inner wall surfaces 2 and 3; an operation of the transport arms to enter the lower surface side space;
and the cassette of the transport arm after the substrate 10 is transferred from the holding part 3a to the transport arm and positioned in the upper surface side by relative displacement in the vertical direction between the transport arm and the cassette case. Horizontal conveyance members 16, 4 that move horizontally together with the conveyance arm for an exit operation out of the case.
1, 42, a horizontal guide member 31 that guides the horizontal movement of the horizontal conveyance member, and the horizontal guide member and the cartridges 14, 15.
and moving means 30, 3 for moving relative to each other in the vertical direction.
2 to 37, and a support member disposed adjacent to one side edge of the door member 1 of the cassette case so that the vertical positional relationship is substantially constant with respect to the horizontal guide member 31. 23, when the transport arms 16a and 16b face the closed door member 1 at a height approximately equal to the lower surface side gap in the desired cassette case, a non-receiver is attached to the back side of the engaging portion 8a of the door member. an opening/closing movable member 2 provided on the supporting member 23 so as to be in contact with the door member and to engage with the contact surface on the back side of the engaging portion by a drive source 27 and press the door member from the back side;
0, and when each door member 1 of the plurality of cassette cases is closed, the moving means 30, 32 to 37
When the transport arms 16a, 16b and the plurality of cassette cases move relative to each other in the vertical direction, the opening/closing movable member 20 engages the engaging portion 8a formed on each door member of the plurality of cassette cases.
1. A substrate conveying device characterized by sequentially displacing the back side of the substrate in a vertical direction in a non-contact manner. 2. The moving means 30, 32 to 37 fix the horizontal guide member 31 and move the cartridge 14,
vertically moving member 3 that moves in a direction perpendicular to 15;
0, and the support member 23 is integrally fixed to the horizontal guide member 31 via the vertically moving member. 3. The opening/closing movable member 20 is rotatably supported by the support member 23 via a rotating shaft 19 substantially parallel to the shaft 6, and is driven by the drive source 27 when opening/closing the door member 1. The conveyance device according to claim 1 or 2, wherein the movable opening/closing member 29 is moved in a circular motion. 4. The conveying means according to claim 1, wherein the moving means 30, 32 to 37 move the cartridge in the vertical direction with respect to the horizontal guide member 31 and the support member 23. 5. The moving means 30, 32 to 37 move the opening/closing movable member 20 to the engaging portion 8a of the door member 1 after the transport arms 16a, 16b enter the space on the lower surface side of the cassette case. 2. The conveying device according to claim 1, wherein the substrate 10 is driven in the vertical direction until the substrate 10 is slightly lifted from the holding portion 3a while the door member is engaged and opened substantially horizontally.