JPH0780568B2 - Substrate transfer device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate transfer device for automatically transferring a thin plate-like object (hereinafter referred to as a substrate) such as a reticle or a mask in a semiconductor manufacturing apparatus.

Note that the description using the reticle as an example in the present specification can be similarly applied to the mask.

[Prior Art] In a semiconductor photolithography process, in order to form a pattern on each chip of a wafer, an actual size pattern mask is brought into close contact with the wafer surface for exposure baking, or several times to about 10 times the actual size. A reticle on which a pattern for one chip is formed is reduced through an optical means and projected onto a wafer for pattern printing.

In order to complete one semiconductor device, this pattern printing process is usually performed several times to several tens times for one wafer. Specifically, first, the reticle of a certain mask process is set in the exposure apparatus, and the pattern printing process is performed on a predetermined amount (for example, 100) of wafers. Wafers that have undergone the baking process are subjected to etching, impurity diffusion, formation of conductor layers, insulating layers, semiconductor layers, photoresist coating, etc. as necessary, and then the reticle is used in the next mask process. The wafer is replaced and the pattern printing process of the reticle is performed on all of these wafers. Thereafter, the baking process is similarly repeated to obtain a wafer having a desired pattern.

By the way, reticles used in such a printing process are housed in the reticle cassette one by one. And
The desired substrates are taken out from the multiple cassettes housed in the cassette library fixed to the main body of the exposure apparatus, and the long substrate transport path is followed to the substrate dust inspection device. It is configured so as to follow the transfer path and feed it to the exposure position in the main body apparatus, and the substrate transfer path is the same for both the forward and return paths.

[Problems to be Solved by the Invention] However, in such a conventional substrate transfer apparatus, when exchanging a substrate, the next substrate is removed until the unused substrate is removed from the path, that is, the storage process is completed. However, there is a problem in that it takes a long time to replace the substrate and the waiting state for the substrate of the apparatus becomes long.

Generally, semiconductor manufacturing lines include a low-mix / high-volume production type line and a high-mix / low-volume production type line. In the latter line, board replacement is frequently performed, The long waiting time of the substrate in the device has a problem of significantly reducing productivity.

On the other hand, a substrate transfer device has been proposed in which a part of the forward path and the return path of the transfer path are separated so as to be compatible with a high-mix low-volume production line, but it has a drawback that the mechanism for transferring the board becomes complicated.

The present invention eliminates the above-mentioned drawbacks in the conventional example, and particularly when exchanging the substrate of the exposure apparatus, the exposure apparatus can be adapted to a high-mix low-volume production type line, and a complicated transfer mechanism is not required. An object is to provide a carrier device.

[Means and Actions for Solving Problems] In order to achieve the above-mentioned object, the substrate transfer device according to the present invention is configured such that a movable hand carrying a substrate is horizontally inserted into a substrate storage rack or The board is delivered between the hand and the storage shelf by pulling out and raising and lowering the board storage shelf as a whole.

Thus, it is possible to carry out and carry in the substrate without providing a mechanism for vertically moving up and down the hand for carrying in and carrying out the substrate, which is seen in the conventional reticle transport apparatus.

It should be noted that the substrate storage shelves may be arranged in a stack by using a plurality of containers for individually storing the substrates, for example, in the case of applying to a reticle changer, a plurality of reticle cassettes for storing the reticle.

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

FIG. 1 is a schematic configuration diagram of a transfer mechanism portion of a high-speed reticle changer to which a substrate transfer device according to an embodiment of the present invention is applied.

In the figure, reference numeral 1 is a reticle library for holding a plurality of reticle cassettes 5 for accommodating one reticle one by one and moving them in the vertical direction (arrow A1 in the figure). A door opening / closing mechanism (not shown) is provided at a fixed position corresponding to the reticle take-out position of the reticle library 1. 2 is a reticle 6 from inside the reticle cassette 5
Is a withdrawal hand for taking out, storing, and carrying. The drawer hand 2 can move in the direction of arrow A2. When the reticle 6 is taken out by the drawing hand 2 and conveyed, the bar code of the reticle 6 is simultaneously read by a bar code reader (not shown) provided beside the conveyance path. Reference numeral 3 is a quick hand that has two holding portions 7-1 and 7-2 for holding the reticle 6 by vacuum and can hold two reticle 6 at the same time. The quick hand 3 can be moved in the vertical direction (arrow A3) or can be rotated around the shaft 8 (arrow A4).
Then, the reticle 6 is delivered from the drawing hand 2 to the sending hand 4, and the old and new reticle 6 are exchanged.

Reference numeral 4 denotes a delivery hand for delivering the reticle 6 to the aligner body and for positioning the reticle 6 with respect to the aligner body. The feeding hand 4 can be rotated around an axis 9 (arrow A6) or can be moved vertically (arrow A6).
5) can be moved to.

The operation of loading the reticle 6 in the above configuration will be described.
This will be described with reference to the flowchart of FIG.

First, in step S11, the reticle library 1 is moved up or down to a predetermined position in order to pull out a specified (slot) reticle. Next, in step S12, the door of the reticle cassette 5 is opened. This opens the opening for pulling out the reticle 6 from the reticle cassette 5. The door is opened and closed by a cassette door opening / closing mechanism attached to the reticle library 1. Next, in step S13, the drawer hand 2 is advanced toward the reticle cassette 5. next,
In step S14, the reticle library 1 is lowered by a distance required for delivering the reticle 6. In this state, the reticle 6 is placed on the drawer hand 2. Then step
At S15, the vacuum of the drawer hand 2 is turned on, and the reticle 6 is held. Next, in step S16, the drawer hand 2 is retracted to return to the home position. Step during this operation
At S17, the bar code reading operation is performed at the same time. After confirming that the drawer hand 2 has retracted in step S18,
The door of the cassette 5 is closed in step S19. Sequence above The reticle 6 to be used next in advance by the pulling hand 2
Prepare on top.

Next, in step S20, the quick hand 3 is lowered, in step S21, the vacuum of the holding portion 7 of the quick hand 3 is turned on, in step S22, the vacuum of the drawer hand 2 is turned off, and the reticle 6 on the drawer hand 2 is removed. Adsorb to the quick hand 3. Then, in step S23, the quick hand 3 is lifted to lift the reticle 6. next,
At step S24, the quick hand 3 is rotated 180 ° about the axis 8 to replace the reticle 6, and the feeding hand 4
The reticle 6 is moved to the position. At this time, the sending hand 4 is assumed to be located immediately below the holding portion 7-2 of the quick hand 3. Thereafter, in step S25, the quick hand 3 is lowered, in step S26, the vacuum of the sending hand 4 is turned on, in step S27, the vacuum of the quick hand 3 is turned off, and the reticle 6 is delivered to the sending hand 4. Then, in step S28, quick hand 3
Raise.

The reticle 6 that has been used up and the reticle 6 to be used next are exchanged by the above sequence (1 to 2 in FIG. 2).

Next, in step S29, the reticle 6 is positioned with respect to the aligner body by the reticle positioning mechanism attached to the sending hand 4. Then, in step S30, the reticle 6 is sent to the aligner body by the sending hand 4.

Sequence above Then, the reticle 6 is set on the aligner body.

As described above, the operation of loading the reticle into the aligner body is performed.

Next, the operation of carrying out the reticle 6 will be described with reference to the flowchart of FIG.

First, in step S31, the sending hand 4 is returned to the changer side to carry out the reticle from the aligner body. Next, in step S32, the quick hand 3 is lowered, in step S33, the vacuum of the holding portion 7 of the quick hand 3 is turned on, and in step S34, the vacuum of the sending hand 4 is turned off. Then, the reticle 6 on the feeding hand 4 is sucked by the quick hand 3, and the quick hand 3 is lifted as it is in step S35. After that, in step S36, the quick hand 3 is rotated by 180 ° around the axis 8, and then in step S37, the quick hand 3 is lowered. And
In step S38, turn on the vacuum of drawer hand 2,
In step S39, the vacuum of the holding portion 7 of the quick hand 3 is turned off, and the reticle 6 is delivered onto the drawer hand 2. Next, in step S40, the quick hand 3 is raised.

The reticle 6 is exchanged according to the above sequence (from FIG. 3). It should be noted that this part is the same in operation as the part for reticle exchange in the sequence of FIG. Therefore,
With a single operation, it is possible to simultaneously realize two actions, that is, the loading sequence and the unloading sequence.

Next, in step S41, the reticle library 1 is moved to a predetermined position, and then in step S42, the door of the cassette 5 for storing the reticle 6 to be carried out is opened.

A cassette for carrying out is prepared by the above sequence (from FIG. 3).

Next, in step S43, the drawer hand 2 is moved forward, in step S44, the vacuum of the drawer hand 2 is turned off to release the suction of the reticle 6, and in step S45, the reticle library 1 is raised by a distance required for delivery, S46
Move the drawer hand 2 backward with. This action causes reticle 6
Are stored in the cassette 5. Then, step S47
Then the door of cassette 5 is closed.

Sequence above Thus, the reticle 6 is stored in the cassette 5.

As described above, the operation of carrying out the reticle from the aligner body is performed.

Next, the operation of replacing the reticle will be described with reference to the flowchart of FIG.

First, the sequence Reticle carry-out operation. Then the sequence ~
The reticle replacement operation is performed. As a result, the loading operation sequence (reticle exchange) is automatically executed.

Next, sequence ~ cassette preparatory operation and sequence Reticle storage operation and sequence The reticle and the aligner are set in parallel at the same time.

Sequence for aligner body At the end of, the reticle exchange end is notified.

Then select the reticle you plan to use next. To prepare. At the end of this operation, the reticle exchange is completed.

The present embodiment can be modified and implemented as follows.

For example, in FIG. 4, the sequence of cassette carrying-out operations in the carry-out operation is the sequence Or in parallel with the sequence ~, It is also possible to operate during.

Further, in the reticle library 1 of the present embodiment, the reticle 6 in the cassette 5 is generally protected from dust by the airtightness of the cassette 5. However, by providing the reticle library 1 with a cassette pressing mechanism, higher airtightness can be obtained. It is possible to obtain

According to the present embodiment, the drawbacks in the conventional reticle conveyance, in which the conveyance path is the same for the forward and return paths, are alleviated. That is, the next reticle could not be fed until the unused reticle disappeared from the transport path when the reticle was replaced, but according to the present embodiment, the used reticle from the aligner body is used next. The reticle and the reticle can be placed on the transfer path at the same time and replaced.

Moreover, the structure of the transport mechanism is simple. That is, the reticle library only moves up and down, the withdrawing hand moves forward and backward, and the quick hand and the sending hand only move up and down, respectively, which allows efficient reticle replacement.

Further, in the present embodiment, the side of the reticle library in which the cassettes containing the reticles are arranged in a stack is moved up and down to remove the reticles from the cassette. Therefore, the vertically moving mechanism of the drawer hand, which is conventionally required, is unnecessary.

Further, since the position where the reticle is pulled out from the cassette is always constant, the reticle is fixed at that position and a cassette door opening / closing mechanism is provided. That is, the door opening / closing mechanism conventionally provided on the side of the drawer hand becomes unnecessary, and the door opening / closing mechanism can be provided at the fixed position. This allows the drawer hand to have a simple structure.

Next, the dustproof container used in the reticle changer of this embodiment will be described.

FIG. 5 is a perspective view of the dustproof container used as the reticle cassette in the present embodiment in an open state, and FIG. 6 is a cross-sectional view of a main part configuration in the closed state.

In FIG. 5, an upper lid 101 and a lower tray 102 form a closed housing.
103 is composed. The upper lid 101 is hinged to the lower plate 102 so that it can be opened and closed on the back side. On the front of the top lid 101 is the substrate 1
An opening 104 (Fig. 6) for automatic access of 10 is formed. A door 105 for sealingly covering the opening 104 is hinged to the upper lid 101. The door 105 is always biased by a spring 106 in the closing direction. The lower plate 102 is provided with four pins 109 for supporting the board mounting. Further, stoppers 111 for positioning the substrate are provided on the left and right side surfaces and the rear surface inside the lower plate 102. Substrate such as reticle 1
The stopper 10 is guided by the stopper 111 and placed on the pin 109. A pair of elastic insertion type locking members 107 and 108 are attached to the outer side surfaces of the upper lid 101 and the lower tray 102, respectively.
1 and the lower plate 102 are combined. On the inner surface of the upper lid 101, four cantilevered leaf springs for pressing the substrate, one end of which is fixed to the upper lid side.
112 is installed. As shown by the solid line in FIG. 6, each leaf spring 112 is configured such that its free end side presses the substrate 110 housed in the lower tray 102 from above toward the pin 109 side. A pressure release member 113 made of a shape memory alloy is engaged with each leaf spring 112. The pressure releasing member 113 is substantially U-shaped, and a tip portion 113b abuts the leaf spring 112, and both root portions are connected to a terminal 113a fixed to the upper lid side. Each terminal 11
3a are connected in series by pattern wiring or a suitable wiring means 114, or electrode terminals 115 on the outer side surface of the upper lid 101.
Connected to. The electrode terminal 115 is provided at a position where it is connected to an unillustrated energizing terminal provided in the reticle library 1 when the dustproof container is inserted into the reticle library 1. The shape memory alloy forming the pressure release member 113 is normally used as shown in the solid line in FIG.
Has a shape that does not hinder the application of pressing force to the substrate 110, and moves upward by passing a current through the electrode terminal 115 to lift the leaf spring 112 and separate it from the substrate 110 (dotted line in FIG. 6). ) To be transformed.

The substrate 110 is housed in the dust-proof container having the above structure and the upper lid 1
By closing 01, the substrate 110 is moved to the pin 10 by the leaf spring 112.
9 Pressed on and fixedly held. Such a dustproof container is set by stacking in a plurality of stages as shown in the reticle cassette 5 in FIG. 1 in an automatic substrate attaching / detaching mechanism connected to, for example, an exposure printing apparatus.

When the substrate is automatically taken out, the pressure releasing member 113 made of a shape memory alloy is energized. As a result, the shape memory alloy is heated and deformed, and as shown by the dotted line in FIG.
Is separated from the substrate 110 to release the pressing force. In this state, the door 105 is opened (dotted line in FIG. 6), and the substrate 110 in the container is taken out by the automatic loading and unloading mechanism (not shown). Board 1
When the substrate 110 is automatically stored again in the container after the use of 10, when the shape memory alloy is energized, the substrate 110 is stored in the container.
When the current is cut off after the insertion, the shape memory alloy returns to the shape of the solid line after being placed on the pin 109, and the leaf spring 112 presses the substrate 110 again to fix and hold it on the pin 109.

It should be noted that the number, arrangement position, shape, etc. of the leaf springs 112 that are the substrate pressing means are arbitrary. Also, the method of connecting the electrodes of the shape memory alloy, the electrode terminal lead-out position, etc. are arbitrary, and the electrode terminal 11 is placed at an optimum position according to the structure of the device in which the container is to be mounted.
5 can be provided. For example, in FIG. 5, 4
Although two shape memory alloys are connected in series and both ends thereof are drawn to two electrode terminals, two ends of each shape memory alloy may be drawn to two electrode terminals 115 in total, that is, eight electrode terminals 115.
Alternatively, the terminals 113a may be connected and wired so that only the required shape memory alloy can be selectively energized, for example, by drawing a wire from the position of the point 114a in FIG. 5 to one electrode terminal 115.

Instead of directly energizing the pressing release member 113 to operate it, a rubber heater or other suitable heating means as shown in FIG.
121 may be used to heat the pressing and heating means directly or from outside the container via a suitable heat transfer material.

Further, as shown in FIG. 8, the pressing releasing member 113 may be operated by irradiating a heat ray 122 such as infrared rays instead of passing the electric current.

Further, instead of the shape memory alloy of the above embodiment, a bimetal 123 may be used as shown in FIG. 9 to deform the leaf spring 112 so as to separate it from the substrate during heating. Also, leaf springs
112 itself may be formed of bimetal. Alternatively, as shown in FIG. 10, the substrate 110 may be held on the upper lid 101 side and the substrate 110 may be pressed and fixed by a leaf spring 124 from the lower tray 102 side. Further, as shown in FIG. 11, plate springs 125 and 126 may be provided on both the upper lid 101 and the lower plate 102 to press and hold the substrate 110 from both sides of the substrate 110.

Further, as shown in FIG. 12, a bimorph such as a piezo or a monomorph element 127 may be used to deform the leaf spring 112 so as to separate it from the substrate when energized. In this case, a solar cell or the like may be built in the container and used as a power source.

Alternatively, magnetic force can be used as shown in FIGS.
In FIG. 13, a pattern 128 made of a magnetic material is formed around the substrate 110, and the pin 109 is replaced by a permanent magnet 129. Substrate 110 instead of this magnetic material pattern 128
You may comprise the circumference | surroundings of a magnetic body. Coil 1 on magnet 129
30 is wound, and by energizing this, the magnet 12
The magnetic force of 9 is canceled by the electromagnetic force of the coil 130. As a result, the substrate 110 is pressed and released.

In FIG. 14, the leaf spring 112 is deformed by the electromagnet 131 so as to be separated from the substrate.

In FIG. 15, first, by energizing the coil 132, the magnetic force of the permanent magnet 133 is increased to attract the leaf spring 112 and press the substrate 110. In the normal state, the leaf spring 112 is located apart from the substrate 110, but once it is attracted to the magnet 133, the coil 132 is placed.
Even if the current is cut off, the magnetic force keeps holding the substrate 110. To release the pressing force, a current may be applied to the coil 132 in a direction to cancel the magnetic force of the magnet 133.

On the other hand, the opening 104 of the dustproof container is opened and closed by various methods. For example, in the dustproof container described with reference to FIGS. 5 to 15, the door 105 can be opened and closed by external control using a shape memory alloy. FIG. 16 is a plan view and a side view of a dustproof container provided with such a mechanism.

In the figure, a door 105 for hermetically covering the opening 104 is joined to the upper lid 101 by a hinge 119, and the door 105 is always biased by a spring 106 in a closing direction. The top lid 101 and the door 105 are connected by a shape memory alloy 116. This shape memory alloy 1
16 is deformed in the direction of opening the door 105 when it reaches a predetermined temperature due to energization or the like. Reference numeral 117 is an appropriate wiring means connecting the two shape memory alloys 116, and 118 is an electrode terminal exposed on the outer side surface of the upper lid 101.

When the board is automatically taken out, the electrode terminal 11
The shape memory alloy 116 is energized via 8. As a result, the shape memory alloy 116 is deformed, and the door 105 of the upper lid 101 is opened as shown in FIGS. 16 (a) and 16 (c). Then, as described above, the shape memory alloy 113 is energized to release the pressing of the substrate 110, and the substrate 110 in the container is taken out by the automatic loading / unloading mechanism. After using the substrate 110, when the substrate 110 is automatically stored again in the container, the substrate 110 is inserted into the container with the shape memory alloy 116 energized and the door 105 is opened, and the substrate 110 is placed on the pin 109. When the post current is cut off, the shape memory alloy 116 returns to its original shape by the spring 106, and the door 105 closes the opening 104 of the upper lid 101 again.

The number, arrangement position, shape, etc. of the shape memory alloy 116 are arbitrary. Also, a method of connecting electrodes of shape memory alloy,
The electrode terminal lead-out position or the like is arbitrary, so that the electrode terminal 118 can be provided at an optimum position according to the device structure to which the container is to be attached, and only the necessary shape memory alloy 116 can be selectively energized. You can also

Further, instead of directly energizing the shape memory alloy 116 to operate it, the pressing and heating means may be heated using a rubber heater or other suitable heating means directly or from outside the container via a suitable heat transfer material.

Further, the shape memory alloy 116 may be operated by irradiating a heat ray such as infrared rays instead of passing an electric current.

Further, the door of the cassette may be opened and closed by using a shape memory alloy as described above or mechanically. Figure 17 shows the first
The reticle changer in the figure is an example in which a mechanical door opening / closing mechanism 201 is used to open / close the cassette door, and FIG. 18 shows a reticle cassette used in such a reticle changer. Even in this case, the door opening / closing mechanism can be provided in the fixed portion.

[Effects of the Invention] As described above, according to the present invention, it is possible to insert or pull out a hand for loading and unloading a substrate to and from the substrate storage shelf, and the entire substrate storage shelf. Since it is possible to move up and down, it is not necessary to provide a mechanism for vertically moving the hand itself for loading and unloading the substrate, and the unloading and loading of the substrate can be performed quickly.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a transfer mechanism portion of a high-speed reticle changer to which a substrate transfer device according to an embodiment of the present invention is applied, FIG. 2 is a flowchart for explaining an operation when a reticle is loaded, and FIG. Is a flow chart for explaining the operation when the reticle is carried out. FIG. 4 is a flow chart for explaining the operation when the reticle is exchanged. FIG. 5 is a perspective view of the dustproof container used in this embodiment in an open state, FIG. 6 is a sectional view of a main part of the dustproof container in a closed state, FIGS. 7 to 15 are sectional views of a main part showing another embodiment of the dustproof container, and FIG. 16 is a plan view and a side view of the dustproof container. FIG. 17 and FIG. 17 are schematic configuration diagrams of a transport mechanism portion of a reticle changer using a mechanical door opening / closing mechanism, and FIG. 18 is a diagram showing a reticle cassette for mechanically opening / closing the door. 1: Reticle library, 2: Drawer hand, 3: Quick hand, 4: Feeding hand, 5: Reticle cassette, 6: Reticle, 101: Top lid, 102: Lower plate, 103: Enclosure, 109: Pin, 110: Substrate, 112: Leaf spring, 113: Press release member, 116: Shape memory alloy.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location H01L 21/68 A

Claims (3)

[Claims] 1. A hand on which a substrate is mounted and which is movable in the horizontal direction, a means for inserting or withdrawing the hand into or from a substrate storage shelf for storing the substrate, a means for raising or lowering the substrate storage shelf, and the above-mentioned hand. To the board storage shelf, lower the board storage shelf by a predetermined amount, place the board on the hand, and then pull out the hand to carry the board out of the board storage shelf. Also, place the board-mounted hand on the board storage shelf. And a control means for pulling out a hand to carry the substrate into the substrate storage rack after raising the substrate storage rack by a predetermined amount. 2. The substrate transfer apparatus according to claim 1, wherein the substrate storage rack has a plurality of containers for individually storing the substrates arranged in a stack. 3. The substrate transfer apparatus according to claim 1, wherein the substrate is a reticle or a mask.