JP4805258B2 - Cassette transport system - Google Patents

Description

【Technical field】
[0001]
The present invention relates to a transport system for transporting articles in a facility such as a factory. In particular, the present invention relates to a cassette transport system suitable for storing and transporting a highly clean article such as a semiconductor manufacturing substrate to be processed in a cassette in a highly clean environment. In the present specification, the LCD substrate, which is an electronic component, will be described as an object to be transported using an example of being stored in a cassette and transported. However, this is an example, and the scope of the present invention is not limited. Absent.
[Background]
[0002]
In general, semiconductor manufacturing processes dislike dust, and therefore, the transportation of substrates such as LCDs and semiconductor wafers and the processing thereof are performed in a highly clean environment, a so-called clean room. In the prior art, these substrates are housed in a cassette and are transported in cassette units by an AGV (Automatic Guided Vehicle). These cassettes include a sealed cassette and an open type cassette. Sealed cassettes can suppress the adhesion of dust to the substrate as much as possible, but there are also problems such as increased weight and the risk of damage to the substrate due to vibration, and are adopted for glass substrates and large substrates. However, it is mainly used for transporting wafers of 300 mm or less. An open cassette is generally used as a cassette for storing a glass substrate or a large substrate.
[0003]
The cassette transported to the target processing apparatus by the AGV is placed on a cassette mounting table (load port) provided in front of the processing apparatus. Thereafter, the substrate is taken out one by one from the cassette placed on the placement table by a known SCARA robot and carried into each processing apparatus. The substrate carried into the processing apparatus is subjected to predetermined processing within the processing apparatus. When the processing is completed, the substrate is taken out from the processing apparatus, stored and sealed in a cassette, and transferred to the next destination (processing apparatus or storage chamber).
[0004]
Patent Document 1 discloses a transport system that takes out a substrate from a cassette placed in a predetermined place and transports the substrate to a target processing apparatus. In this transfer system, a SCARA robot is provided in the transfer device itself, and the SCARA robot takes out the substrate from the cassette and places the substrate on a predetermined mounting table on the transfer device. When the transfer device on which the substrate is mounted moves to the target substrate processing apparatus, the substrate on the mounting table is lifted and moved by the SCARA robot of the transfer device, and the transfer of the substrate is completed. Thus, by providing one SCARA robot in the transfer apparatus itself, it is not necessary to install a SCARA robot for each substrate processing apparatus.
[0005]
[Patent Document 1]
JP 2001-168169 A
DISCLOSURE OF THE INVENTION
[Problems to be solved by the invention]
[0006]
However, recently, the size of substrates to be processed has increased, and for example, a sixth generation liquid crystal substrate manufacturing plant uses a large substrate of about 1500 × 1800 mm. In such a manufacturing factory, in order to perform various processes such as a cleaning process before forming a thin film, a thin film forming process, a resist coating process, etc., such a large substrate is placed in a place necessary for processing processes (arrangement of processing apparatuses). Must be moved to the place).
[0007]
Thus, when the board | substrate to convey is enlarged, the cassette which accommodates the board | substrate will also be enlarged. In order to transport a large-sized cassette with the conventional AGV, not only the size of the AGV cassette mounting table is increased, but also the robot arm mounted on the AGV is enlarged, and the entire AGV is enlarged. When the AGV becomes large in this way, the weight of the AGV increases, so that the entire transport system including the transport path that supports and transports the AGV becomes large. As the weight of the AGV increases, the durability of the transport mechanism that supports and transports the AGV and a high-output drive device are required, so the entire device becomes larger. In addition, when a heavy substrate that has been increased in size by conventional technology is transported, an increase in dust due to an increase in sliding friction also becomes a problem. Thus, in the semiconductor manufacturing process, there are various problems to be solved as the substrate becomes larger.
[0008]
Conveying by conventional AGV by reducing the number of large substrates in the cassette as much as possible and reducing the weight of the entire cassette as much as possible is also considered as one of means for avoiding the above-mentioned problems. However, if the number of cassettes stored is reduced, the transport capability (transport capability) decreases. In recent years, the capability of each processing apparatus for manufacturing semiconductors has been greatly improved. If the transfer capability is reduced, the transfer capability becomes a bottleneck, and the overall production capability is reduced. Accordingly, there is a demand for a substrate transport capability capable of supplying a large substrate according to the processing speed of each processing apparatus. That is, there is a demand for a transfer apparatus that can stably supply a large substrate to each processing apparatus at high speed without generating dust.
[0009]
The transport device of Patent Document 1 transports a substrate taken out from a cassette, and the entire installation environment of the transport device must be maintained in a clean state. As the substrate becomes larger, the transport path becomes longer, and such a transport system requires a large cost just to maintain a clean environment. Moreover, in the conveyance system of patent document 1, the conveyance apparatus which can drive | work on one conveyance path is limited to one unit. With this, the total amount that can be distributed on the line is greatly limited, and it is not possible to respond to a request for a transport capability (transport capability).
[0010]
On the other hand, when the substrate is stored in the cassette, both ends of the substrate are supported by the support end portions provided in the cassette, and the central portion of the substrate is slightly lowered and bent. If the base becomes larger (longer), the amount of deflection at the center will also increase. Therefore, when transporting a large substrate stored in a cassette, if the substrate is not gently transported, the central portion of the substrate may be greatly shaken by vibration, and the substrates may collide and be damaged. In the transport method according to the prior art, the cassette is delivered by raising and lowering it with a lift before and after the transport.
[0011]
When the cassette is transported, a lift claw is inserted into the bottom of the cassette and lifted. For this reason, if a claw is inserted into the bottom of an enlarged cassette and lifted, the cassette itself is also bent, and there is a possibility that the substrate stored inside the cassette is damaged.
[0012]
Furthermore, it is desirable to use a sealed cassette that can suppress the adhesion of dust for transporting the substrate. For this purpose, it is required that a heavy cassette can be transported accurately while suppressing vibration. However, this has various problems. For example, in a large cassette having a lid and having a heavy weight, if the large cassette is lifted by a lift during transportation, the cassette itself bends, and there is a possibility that a gap may be formed even if the lid is sealed. Further, when lifted by a lift, vibrations are large, and internal substrates may collide and be damaged.
[0013]
It is an object of the present invention to provide a cassette carrying system capable of smoothly carrying a heavy cassette such as a cassette containing a large substrate or a glass substrate without damaging the substrate while suppressing vibration. To do.
[0014]
Another object of the present invention is to provide a cassette carrying system that generates less dust due to sliding friction of the carrying device.
[Means for solving problems]
[0015]
The cassette transport system of the present invention is configured to float the cassette by jetting high-pressure gas, and to move the floated cassette to a target position along the transport path by a transfer arm provided in the transport path. Resolve.
[0016]
A first aspect of a cassette transport system according to the present invention is a cassette transport system for transporting a large cassette containing a large transport object therein to a desired position along a predetermined transport path in a clean environment. A levitation apparatus comprising: a compression unit that compresses gas to generate high-pressure gas; and an ejection unit that ejects the compressed high-pressure gas from a plurality of ejection ports, and the cassette floats on the conveyance path by ejection of the high-pressure gas And at least one transfer arm capable of holding and releasing the cassette, and transferring the transfer arm in the horizontal direction along the transport path in a state where the floated cassette is held by the transfer arm. The cassette is controlled by controlling the cassette transfer device and the gas ejection by the levitation device and the cassette transfer by the cassette transfer device. A conveyance control unit that conveys the position, characterized in that it comprises a.
[0017]
According to this aspect, the floating cassette can be moved in the horizontal direction by holding the cassette levitated by the transfer arm and moving the transfer arm in the horizontal direction while holding the cassette. At least one transfer arm may be used, but a plurality of transfer arms may be provided according to the transport mode. For example, even if one transfer arm is provided on one side of the transfer path, two transfer arms are provided so as to be paired on both sides of the transfer path, and the cassette is held between the transfer arms on both sides. It is good also as composition to do. In the cassette carrying system according to this aspect, since the cassette is levitated, the cassette can be easily moved by applying an external force in the horizontal direction. The levitation device may be lifted about several millimeters that can move the cassette. The gas to be ejected may be clean air or a special gas. Further, since the large-size cassette is held horizontally by the transfer arm, the transfer arm can accurately control operations such as acceleration and deceleration when the cassette is moved in the horizontal direction by the transfer arm. Therefore, it is possible to transport the cassette while suppressing vibration. As described above, since the cassette is floated by the high-pressure gas and then moved horizontally, it is not necessary to increase the strength of the transfer arm, and the transport mechanism is simplified. Further, since there are almost no sliding parts, it is possible to suppress the generation of dust due to sliding wear, and it becomes easy to maintain a clean environment. In particular, when a heavy article is transported by a mechanical transport device, the generation of dust due to the sliding friction of the transport device itself increases, so the effect of suppressing dust generation by floating the cassette is great.
Further, when the cassette is placed at the target position, the cassette can be placed gently by gradually dropping the ejected air.
[0018]
A second aspect of the cassette transport system according to the present invention is the cassette transport system according to the first aspect, wherein at least one of the transfer arms is linked to at least two arm members, and the two or more arms are connected. The cassette held at the tip of the transfer arm is moved in the horizontal direction by driving the member to bend and extend by the link coupling portion.
For example, one end of two arms is connected by a joint, the cassette is held at the tip of one arm, and the cassette is moved in the horizontal direction by extending and contracting the two arms along the transport path. To do. As a result, it is possible to accurately control the braking operation associated with the horizontal movement of the cassette with a transfer arm having a simple structure. The transfer arm is not limited to two joints, and may be multi-joint.
[0019]
A third aspect of the cassette transportation system according to the present invention is the cassette transportation system according to the first aspect, wherein at least one of the transfer arms is horizontally moved along the transportation path while holding the cassette. A moving part is provided. For example, it is possible to configure the transfer arm with only one arm, provide a cassette holding part for holding the cassette at one end, and drive the other end in the horizontal direction along the transport path. . For example, in the case of transfer in the linear direction, the transfer distance by one transfer arm can be increased by adopting a configuration in which the transfer arm can be moved horizontally. Moreover, high speed conveyance is possible by increasing the transfer distance. As the horizontal driving means, for example, a driving device that can be linearly driven via a ball screw shaft by the operation of a motor, a magnet is provided in a cylindrical shaft so that N poles and S poles are alternately arranged, and is movable. A well-known means such as a linear drive device that includes a coil on the member side and can be driven on a straight line or a curve by passing a current through the coil can be used.
[0020]
According to a fourth aspect of the cassette transport system of the present invention, in the cassette transport system of the first aspect, the transfer arm of the cassette transfer device is provided on both sides of the transfer path along the transfer path. It is characterized by being. By providing the transfer arms on both sides, it is possible to reliably hold the object to be transported, and it is possible to stably transfer while suppressing vibration.
[0021]
According to a fifth aspect of the cassette transport system of the present invention, in the cassette transport system according to any one of the first to fourth aspects, the jet part of the levitation device is provided on the upper surface of the transport path, and the jet part The cassette placed on the transport path is levitated by ejecting high-pressure gas upward from the top. In this aspect, since the high-pressure gas is ejected from the conveyance path surface toward the cassette, a compression pump that generates high-pressure gas or a storage cylinder that temporarily stores high-pressure gas can be disposed under the conveyance path surface, which is relatively simple. It becomes possible to set it as a simple structure.
[0022]
According to a sixth aspect of the cassette transport system of the present invention, in the cassette transport system according to the fifth aspect, the ejection portion of the levitation device is divided and arranged in a predetermined unit along the transport path. The high-pressure gas can be ejected for each divided unit, and the transport control device sequentially switches the high-pressure gas ejection position of the levitation device in accordance with the movement position of the cassette on the transport path. It is characterized by controlling as follows. According to this aspect, the high-pressure gas can be ejected only in the vicinity of the moving cassette or in the vicinity thereof. Therefore, efficient use of high-pressure gas becomes possible.
[0023]
A seventh aspect of the cassette transport system according to the present invention is the cassette transport system according to the fifth aspect, wherein the cassette transport device includes a plurality of transport arms along the transport path, and the cassette is levitated. By moving the transfer arm in the horizontal direction along the transfer path while the cassette is held by the transfer arm, and passing the cassette in a state where the cassette is levitated to another adjacent transfer arm. Is transported to a target position. For example, according to the length of the conveyance path, it is possible to carry a long distance by providing a plurality of transfer arms of various forms at predetermined intervals and transferring the cassettes one after another in a relay manner. is there. Moreover, it is also possible to configure so as to switch the transport direction by switching the transfer arm.
[0024]
According to an eighth aspect of the cassette transport system of the present invention, in the cassette transport system according to any one of the first to fourth aspects, the ejection portion of the levitation device is provided on a lower surface of the cassette, and The cassette is levitated by injecting high-pressure gas into the conveyance path. Although it may be configured such that the compression pump is mounted on the levitating device on which the cassette is placed and moved together with the cassette, the levitating device can be reduced in size and weight by being configured to supply high-pressure gas to the levitating device from the outside. preferable.
[0025]
According to a ninth aspect of the cassette transport system of the present invention, in the cassette transport system according to the eighth aspect, the levitation device holds the cassette and the pipe provided in the transfer arm from the compression section. A high-pressure gas is supplied to the injection unit provided in the lower part of the cassette via a holding unit.
[0026]
According to a tenth aspect of the cassette transport system of the present invention, in the cassette transport system according to the ninth aspect, the cassette transfer device includes a plurality of transfer arms along the transfer path, and is floated. By moving the transfer arm in the horizontal direction along the transport path while holding the cassette by the transfer arm, and passing the cassette while floating to the other adjacent transfer arm, The cassette is transported to a target position.
[0027]
An eleventh aspect of the cassette transport system according to the present invention is the cassette transport system according to the tenth aspect, wherein the transport control device supplies the high-pressure gas from the compression section in response to delivery of the cassette by the transfer arm. Control is performed so as to sequentially switch the transfer arms to be supplied. Thereby, whenever the transfer arm is switched, the high-pressure gas is appropriately supplied to the jet outlet of the cassette via the transfer arm connected to the cassette.
[0028]
According to a twelfth aspect of the cassette transport system of the present invention, in the cassette transport system according to the eleventh aspect, the transport path includes one main line and a branch extending from the main line at a predetermined angle, Each of the main line and the branch is provided with the transfer arm. By providing the branch as described above, it is possible to transfer according to the priority order, such as retracting the cassette transported first to the branch and transporting the subsequent cassette first.
[0029]
A thirteenth aspect of the cassette transport system according to the present invention is the cassette transport system according to the twelfth aspect, further comprising a lifting device for placing and lifting the cassette on any one of the transport paths. Comprises the levitation device on a mounting table on which the cassette is mounted. By providing the elevating means including the levitation device, the cassette can be lifted or lowered from the mounting table without vibrating.
[0030]
[0031]
[The invention's effect]
[0032]
In the cassette carrying system of the present invention, since the cassette is lifted and moved, a load caused by friction when moving the cassette in the horizontal direction can be eliminated, and the drive output in the horizontal direction can be reduced.
[0033]
Further, in the cassette transport system of the present invention, the cassette is levitated by blowing gas over the entire bottom surface of the cassette or by ejecting gas from the entire bottom surface of the cassette. There is no concentrated load on a part of the bottom. That is, since the entire bottom surface is lifted by the floating means, the cassette itself does not bend. Therefore, unlike lifting with a lift, there is no inconvenience such as a gap even if a heavy cassette is sealed with a lid. Further, no special design such as increasing the rigidity of the cassette is required to suppress the bending.
[0034]
In the cassette carrying system of the present invention, since the cassette can be moved without contacting the carrying path and the cassette by the levitation means, generation of dust such as particles due to sliding friction can be suppressed.
[0035]
On the other hand, when the transfer arm is used for horizontal transfer movement, since the cassette is always held by the transfer arm, it is possible to prevent lateral displacement due to external force. In addition, the inertial force that accompanies the movement increases as the cassette becomes heavier, but since the cassette is firmly held by the transfer arm, the inertial force can be accurately controlled and accurately transported to the desired position. Can be stopped. This makes it possible to accurately position a heavy cassette that is heavy on the load port. Further, as described above, suppression of vibration is particularly important in a large-sized substrate, but it is possible to reduce minute vibration caused by the jet gas by holding it with an arm.
[Brief description of the drawings]
[0036]
FIG. 1 is a perspective view showing a cassette carrying system according to a first embodiment of the present invention.
2 is a longitudinal sectional view showing an example of a floating device and a cassette for levitating a cassette in the cassette carrying system of FIG. 1. FIG.
FIG. 3 is a partially cutaway perspective view showing a cassette transfer device provided in the cassette carrying system of FIG. 1;
FIG. 4 is a perspective view showing the raising / lowering means of the cassette of the present invention.
FIG. 5 is a perspective view showing a cassette carrying system according to a second embodiment of the present invention.
FIG. 6 is a perspective view showing a cassette carrying system according to a third embodiment of the present invention.
FIG. 7 is a perspective view showing a cassette carrying system according to a fourth embodiment of the present invention.
FIG. 8 is a side view showing a transport operation of a cassette transfer device according to another embodiment used in the cassette transport system shown in FIG.
9 is a side view showing a transport operation of a cassette transfer apparatus according to another embodiment used in the cassette transport system shown in FIG.
FIG. 10 is a flowchart showing a procedure for transporting a cassette on a lifting device to the main line by the cassette transfer device of the cassette transport system shown in FIG. 7;
FIG. 11 is a side view showing a cassette rotation mechanism according to the present invention for adjusting the orientation of the cassette.
FIG. 12 is a partially cutaway perspective view showing an example of cassette holding means of the cassette carrying system according to the present invention.
FIG. 13 is a functional block diagram showing a schematic configuration of a control unit that controls the operation of the cassette carrying system according to the present invention.
FIG. 14 is a perspective view showing a cassette carrying system according to a fifth embodiment of the present invention.
FIG. 15 is a perspective view showing a cassette carrying system according to a sixth embodiment of the present invention.
FIG. 16 is a diagram for explaining the structure of a cassette holding portion of a cassette transfer arm that supplies high-pressure gas to a cassette that floats by jetting high-pressure gas from the cassette;
FIG. 17 is a perspective view showing a relationship among a cassette transport system, a mini-environment device, and a processing device. A transfer robot is shown in which a part of the mini-environment is cut out and placed inside.
FIG. 18 is a side view of the cassette and the door opening / closing mechanism showing the procedure for opening the lid of the cassette and the movement of the opening / closing mechanism in order, and a part thereof is shown as a cutaway sectional view.
FIG. 19 is a cross-sectional view of the cassette and the door opening / closing mechanism showing the continuation of the opening / closing operation of FIG.
FIG. 20 is a flowchart showing a procedure for opening the cassette lid and the door of the mini-environment device.
FIG. 21 is a perspective view of a bottom surface portion of a cassette for ejecting gas from the bottom surface as viewed from below.
FIG. 22 is a cross-sectional view showing a coupler for supplying high-pressure gas to the cassette and a coupler receiver for connecting the coupler.
FIG. 23 is a cross-sectional view showing levitation means provided at the bottom of the cassette.
24 is a sectional view taken along line AA ′ of FIG.
FIG. 25 is a diagram for explaining a configuration according to another embodiment of the cassette holding unit that supplies high-pressure gas to the cassette.
FIG. 26 is a cross-sectional view showing another embodiment of the cassette and the levitating device provided in the lower part of the cassette.
FIG. 27 is a cross-sectional view of the conveyance path and the cassette for explaining a structure in which the cassette is stopped in a floating state.
[Explanation of symbols]
[0037]
1a-1f Cassette transport system according to one embodiment of the present invention
2 Substrate
3,3e cassette
4,4e Transport path
5 Cassette transfer device
5a to q Cassette transfer arm
6,6e Cassette levitation device
7 main lines
8 processing equipment
9a, 9b Crossroads
10 Lifting device
11 Shift mechanism
12 Substrate removal device
13 Compression pump (compressor)
14 Pressure adjustment chamber
15 Ceiling member
16, 16e spout
17 Pressure control device
18a-18e Horizontal drive unit
19a, 19b Movable member
20a, 20e Cassette holder
21 Motor
22 Ball screw shaft
23 Drive motor
24 First arm
25 pulley
26 belt
27 Power transmission means
28 Second arm
30 base
31 Support member
32 motor
33 Ball screw shaft
34 Drive means
35 Lifting platform
36 Torso
37 Lower arm
38 Upper arm
39 Substrate holding means
40 shelves
41 Bottom shelf
42 Top shelf
43, 43b First cassette holding means
44 Retention recess
44a First holding recess
44b Second holding recess
45 pin lifting device
46 Cassette pin
47 Second cassette holding means
48 Base lifting device
49 base
50 motor
51 mounting table
52 Locating pin
53, 53e Protruding member
54 Projecting member driving means
55 coupler
56 Solenoid valve
57 Piping
58 Mini-environment device
59 FFU
60 grating
61 Door for processing equipment
62 Door
63 opening
64 lids
65 Cassette body
66 Door lift
67 Latch key holder
68 Latch key
69 Door lift
70 coupler receiver
71 Piping
72 opening
73 Pressure sensor
74 Elastic member
75 Valve member
76 Valve member receiver
77 Seal member
78 Coupler body
79 Coupler body
80 Movable valve member
81 Fixing member
82 recess
83 Horizontal movement part
84 holes
85 Cassette holding arm
86 coils
87 Permanent magnet
88 Outlet
89 Inlet
97 Exhaust port
98 Permanent magnet or magnetic material
99 Stop coil
BEST MODE FOR CARRYING OUT THE INVENTION
[0038]
FIG. 1 is a partially cutaway perspective view of a cassette carrying system 1a showing an embodiment of the present invention. In a semiconductor manufacturing factory, such a cassette transport system 1a is arranged in a clean room. The substrate 2 to be processed is transported in a state of being accommodated in a cassette and is carried into each processing apparatus. The reason for storing and transporting the cassette in the cassette is to transport the substrate to the processing apparatus while maintaining a clean environment higher than the clean room atmosphere. The cassette transport system 1 a includes a transport path 4 for transporting a cassette 3 containing a plurality of substrates 2, a levitating device 6 for levitating the cassette 3 on the transport path 4, and a floating cassette 3 as a transport path 4. A cassette transfer device 5 is provided for transfer along. The cassette transfer device 5 has a configuration in which a pair of cassette transfer arms (transfer arms) 5 a, 5 b, and 5 c provided on both sides of the transfer path 4 are sequentially arranged along the transfer path 4.
[0039]
The levitation device 6 provided on the upper portion of the conveyance path 4 includes a large number of holes 16 provided on the upper surface of the conveyance path 4, and high-pressure air or a clean high-pressure gas other than air from the numerous holes 16. Is ejected upward. The cassette 3 is slightly floated on the conveyance path 4 by this gas ejection pressure. In FIG. 1, a main line 4 (7) that is relatively long and a branch 9 (9 a, 9 b) from the main line 4 (7) to the various processing devices 8 are configured. In the reference numeral 4 (7), 4 represents a conveyance path, and (7) represents that the conveyance path 4 is a main line. The numeral (9) of the reference numeral 4 (9) indicates that the conveyance path 4 is a branch. The crossroads (9) are provided with reference numerals 4 (9a) and 4 (9b) according to the position of the crossroads.
[0040]
At the ends of the branches 4 (9a) and 4 (9b), a lifting device 10 that lifts and lowers the cassette 3 and a shift mechanism 11 provided on the lifting device 10 are provided. The shift mechanism 11 is a mechanism for changing the direction of the cassette 3 that can rotate around the vertical axis while the cassette 3 is placed. Further, a substrate take-out device 12 is disposed between the branch 4 (9a) and the branch 4 (9b) in FIG. The substrate take-out device 12 takes out the substrate 2 from the cassette 3 transported to the end position of each branch 4 (9a) or 4 (9b), and inserts (loads) it into the processing device 8 indicated by a broken line in the figure. Alternatively, the processed substrate 2 is taken out from the inside of the processing apparatus 8 and stored in the cassette 3.
[0041]
The cassette transfer device 5 is configured such that the pair of transfer arms cooperate with each other in a state where both sides of the cassette 3 are held by a pair of cassette transfer arms (transfer arms) 5a, 5b, and 5c. The cassette 3 that has been levitated is moved in the horizontal direction along the conveyance path 4 by sequentially transferring the transfer to the adjacent transfer arms 5a to 5c one after another.
[0042]
Each of the transfer arms 5a to 5c includes a protruding member 53 at the tip portion. The cassette transfer device 5 extends the cassette 3 floating in a desired direction by simultaneously extending and contracting the protruding members 53 of the transfer arms 5a to 5c attached to both sides of the cassette 3 and holding the cassette 3. Move.
[0043]
Further, some transfer arms 5 b include a pair of horizontal drive units 18 a that move the transfer arms 5 b in the horizontal direction along the main line 7 of the transport path 4. By moving the transfer arm 5b holding the cassette 3 along the transport path main line 4 (7) by the horizontal drive unit 18a, the cassette 3 can be smoothly transferred to a position where the cassette 3 is transferred to another transfer arm (for example, 5c). Can move long distances.
[0044]
FIG. 2 is a cross-sectional view showing a transverse section of the levitation device 6 that constitutes a part of the conveyance path 4 and levitates the cassette by jetting high-pressure gas from below and the cassette 3 that is levitationed by the high-pressure gas. . The levitation device 6 includes a compression unit and an ejection unit, and the compression unit includes a compression pump 13 and a pressure control device 17, and the ejection unit includes a pressure adjustment chamber 14. The compression pump 13 supplies the compressed high-pressure gas to the pressure adjustment chamber 14 based on the control of the pressure control unit. Many ceilings (holes) 16 are provided in the ceiling member 15 of the pressure regulation chamber 14, and high-pressure gas is ejected upward through the ejection ports 16. In this way, the high pressure gas is strongly ejected upward, and the cassette 3 is floated on the conveyance path 4. Instead of the compression pump 13, a cylinder (high pressure gas storage chamber) for temporarily storing and storing high pressure gas may be provided. In this case, the cylinder is supplied with a high-pressure gas from a compression pump 13 provided outside, and the amount of the high-pressure gas to be fed into the pressure adjusting chamber 14 is adjusted by opening and closing an output valve (not shown). In this way, by storing the high-pressure gas in the temporary storage chamber (cylinder) and then ejecting it, the ejection of the high-pressure gas is controlled more accurately, quickly and efficiently than directly controlling the drive of the compression pump 13. In addition, stable injection control of high-pressure gas is possible.
[0045]
It is preferable to form a transport path having a desired length by modularizing the levitation device 6 into a relatively short length and arranging a plurality of the transport paths 4 in a module (not shown). in this way, Mo By installing the short independent levitating device 6 that is made into a joule continuously, the module of the levitating device 6 that ejects high-pressure gas can be finely switched according to the moving position of the cassette 3. Thereby, since the injection of the high-pressure gas can be stopped in the module in which no cassette is present, the high-pressure gas can be efficiently used.
[0046]
The cassette transport system 1a includes a control device that controls the entire transport operation in order to transport the cassette 3 to a target position. FIG. 13 shows an example of basic functions of the control device as a functional block diagram. The control device 90 is preferably a relatively high performance computer including a central processing unit (CPU), a control program, a logic circuit, and the like. Here, among the various functions of the control device 90, only the central function for transport control, which is the gist of the present invention, will be described.
[0047]
The control device 90 includes a communication interface 91 for enabling cooperative operation with an external computer, a main control unit 92 for controlling the entire operation of the cassette transport system 1a, and pressures of the floating devices 6 for floating the cassette 3. A floating control unit 93 that controls the control unit 17, a conveyance control unit 94 that controls the plurality of transfer arms 5 a to 5 c to operate in a coordinated manner and conveys the cassette 3 to a target position, and a shift mechanism that adjusts the orientation of the cassette 3. 11 and other parts such as an opening / closing control unit 96 for controlling the door lifting mechanism 66 for opening / closing the cassette lid and the door of the mini-employment device, the substrate take-out device 12 and the like. Various control means (not shown) for controlling are provided. The levitation control unit 93 and the conveyance control unit of the control device 90 function as a conveyance control device in the conveyance system in the control of the conveyance operation.
[0048]
The cassette transport system 1a is provided with various sensors for detecting individual operation states in the levitation device 6, the cassette transfer device 5 and the like, and a position for detecting the position of the cassette 3 being transported along the transport path 4. There are sensors and various other sensor groups. Detection signals from these various sensor groups are input as feedback signals to the main control unit 92 and the various control units 93 to 96. In FIG. 1, a shift control unit 95, a door opening / closing control unit 96, and the like are also included in one control device 90. However, the shift control unit 95 that adjusts the door opening / closing control and the cassette orientation includes various processing devices. Each can be controlled independently. In order to simplify the control processing of the control device 90, it is desirable that the control around each processing device such as door opening / closing control and displacement control is controlled by providing a separate control device for each processing device. Since the conventional technology can be used as appropriate for adjusting the orientation of the cassette 3 and controlling the opening and closing of the door, only the floating control means and the conveyance control means will be described below.
[0049]
When the transfer destination of the cassette 3 is designated, the main control unit 92 of the control device 90 provides necessary control information to the individual control units 93 to 96 and the like. The levitation control unit 93 sequentially drives the levitation device 6 corresponding to the current position of the cassette 3 to the conveyance destination of the cassette 3. That is, the pressure of the high-pressure gas in each of the corresponding levitation devices 6 before and after the position where the cassette 3 exists is monitored, and the pressure control device 17 and the like so as to levitate the cassette 3 by sequentially ejecting the high-pressure gas according to the position of the cassette. To control. Further, the transfer control unit 94 holds the cassette 3 by the cassette transfer unit 5 corresponding to the position of the cassette 3, and sequentially transfers the held cassette 3 to the next transfer arms 5a to 5c, thereby moving the cassette 3 to the target position. The operation of each of the transfer arms 5a to 5c is controlled so as to be conveyed.
[0050]
Next, the conveyance operation of the cassette 3 will be described more specifically with reference to FIGS. 3A to 3C are partially cutaway side views showing a series of transport operations for transporting the cassette 3 containing the substrate 2 along the transport path main line 4 (7). In order to show the structure of the substrate 2 and the horizontal drive unit 18a housed in the cassette 3, a part thereof is shown as a sectional view. A pair of transfer arms 5b arranged on both side surfaces of the transport path main line 4 (7) is attached to the horizontal drive unit 18a. The horizontal drive part 18a moves the transfer arm 5b along the conveyance path 4 (7). As a result, the transfer arm 5b moves horizontally along the transport path 4 (7) to a place where the floating cassette 3 is delivered to the next transfer arm 5c (not shown in FIG. 3).
[0051]
As described above, the transfer arm 5b is provided with the cassette holding portion 20a for holding the cassette 3 at its tip (see FIG. 3C). The transfer arms 5a to 5c are arranged on both sides of the cassette 3 by inserting the protruding members 53 provided on the cassette holding portion 20a into holding concave portions 44 (see FIGS. 1 and 2) provided on the side of the cassette. Hold the face. In addition, although FIG. 3 demonstrates the operation | movement using the transfer arm 5b, all the structures and operation | movement of the transfer arms 5a-5c are the same.
[0052]
Prior to describing FIGS. 3A to 3C, an example of the cassette holding portion 20a and the protruding member 53 provided at the tips of the transfer arms 5a to 5c will be described with reference to FIG. FIG. 12 is a partially cutaway perspective view showing the cassette holding portion 20a provided at the tip of the transfer arms 5a to 5c. The cassette holding unit 20a includes a protruding member 53 provided inside the distal ends of the transfer arms 5a to 5c, and a protruding member driving unit 54 such as an air cylinder that drives the protruding member 53. The projecting member drive unit 54 can project or retract the projecting member 53 outward (in the direction of the white arrow in the figure) by supplying a gas such as air. When the protruding member 53 protrudes, the protruding member 53 is inserted into the holding recess 44 of the cassette 3 (the protruding state of the protruding member 53 is indicated by a broken line). As a result, the protruding member 53 of the cassette holding portion 20a is inserted and engaged with the holding concave portions 44 provided on both sides of the cassette 3, so that the cassette 3 is securely held.
[0053]
Returning to FIG. 3 again, the conveyance of the cassette 3 on the conveyance path main line 4 (7) will be described. FIG. 3A shows a state in which the transfer arm 5b holds the cassette 3 at the position of the left end of the transport path main line 4 (7). The transfer arms 5a to 5c are constituted by a first arm 24 and a second arm 28 (FIG. 3C). The cassette holding portion 20a is provided at the tip of the second arm 28, and when the protruding member 53 provided at the tip of the second arm is inserted into the holding recess 44 (see FIG. 2) of the cassette 3, The cassette 3 is held by the cassette holding portion 20a (see FIG. 12) of the transfer arm 5b.
[0054]
In FIG. 3B, the transfer arm 5b holding the cassette 3 is moved from the left end position of the transfer path main line 4 (7) shown in FIG. 3A by the horizontal drive unit 18a from the transfer path main line 4 (7). The state moved to the right end of is shown. The horizontal drive part 18a rotates the ball screw shaft 22 by rotationally driving the horizontal transfer motor 21, and linearly moves the horizontal movable member 19a in the arrow direction. A transfer arm 5b is fixed on the horizontal movable member 19a. As a result, the transfer arm 5b moves to the position shown in FIG.
[0055]
In FIG. 3C, the arm driving motor 23 provided in the first arm 24 is driven to extend the transfer arm 5b, and the cassette 3 is further moved to the right branch 9b (in FIG. 9b) shows the state of movement to (1). As described above, the transfer arm 5b is composed of the first arm 24 and the second arm 28, and the cassette holding means 20a is provided at the tip of the second arm 28. The first arm 24 is provided with power transmission means 27 including a pulley 25 and a belt 26 for transmitting the power of the arm drive motor 23, and the second arm 28 is rotated via the power transmission means 27. Thus, the first arm 24 and the second arm 28 bend and extend. By this bending / extending operation, the transfer arm 5b can be extended by the lengths of the first arm 24 and the second arm at the maximum, whereby the cassette 3 can be further moved horizontally.
[0056]
FIG. 4 is a side view showing an example of the lifting device 10 and the substrate take-out device 12 provided in the cassette transport system 1a. The substrate take-out device 12 takes out the substrate 2 stored in the cassette 3 and inserts it into the processing device 8 (see FIG. 1), or takes out the processed substrate from the processing device and stores it in the cassette 3. The elevating device 10 is a device that adjusts the height of the cassette 3 by elevating a table on which the cassette 3 is placed in order to take out the substrate 2 by the substrate taking out device 12.
[0057]
The elevating device 10 includes two support members 31 provided in cross at both ends of a base 30 provided on the bottom surface. The support member 31 is pivotally supported in a state of being crossed at the center, and is rotatably connected. One support member 31 is connected to the elevating drive unit 34 so as to be horizontally movable. The elevating drive unit 34 includes a motor 32 and a ball screw shaft 33. When the motor 32 rotates, the ball screw shaft 33 linearly moves in the left-right direction in FIG. When the ball screw shaft 33 moves to the left and right, the lower end of the connected support member 31 is moved to the left and right. When the lower end of the support member 31 moves to the left and right, the pair of support members 31 bends and stretches around the crossed rotation shaft, and the lifting platform 35 provided at the upper portion moves up and down.
[0058]
Next to the lifting device 10, a substrate take-out device 12 is provided. The substrate take-out device 12 takes out the substrate 2 from the cassette 3 and carries it into the processing device 8 (see FIG. 1), or takes out the processed substrate 2 from the processing device 8 and stores it in the cassette 3. The substrate take-out device 12 can be rotated on a lower arm 37 that is rotatable in a horizontal plane above the body portion 36, an upper arm 38 that is rotatable on the upper surface of the lower arm 37, and an upper surface of the upper arm 38. A substrate holding arm 39 supported on the substrate is provided.
[0059]
A procedure for transporting the substrate 2 in the cassette 3 from the substrate take-out device 12 to each processing device 8 will be described. First, as shown in FIG. 4A, the substrate holding arm 39 supported on the upper arm 38 is linearly moved to move below the substrate 2 placed on the shelf 40 of the cassette 3. The tip of the substrate holding arm 39 is inserted (moved). Next, the elevating device 10 is lowered and the cassette 3 is lowered until the substrate 2 is supported by the substrate holding arm 39. With the substrate 2 supported by the substrate holding arm 39, the substrate support arm 39 is pulled out from the cassette 3 to take out the substrate 2 from the cassette 3 and transport it to the processing apparatus 8 (see FIG. 1).
[0060]
Thus, the substrate in the cassette 3 is taken out by moving the lifting device 10 up and down in conjunction with the operation of the substrate take-out device. If the cassette 3 is moved up and down by moving the elevating device 10 up and down, and the upper surface (indicated by position S) of the substrate holding arm 39 can cover the range from the lowest level to the highest level of the cassette 3, the substrate take-out device 36 is moved. All the substrates 2 stored in the cassette 3 can be taken out without being moved up and down. FIG. 4B is a diagram illustrating a state where the lifting device 10 is lowered to the lowest position.
[0061]
FIG. 5 shows a cassette carrying system 1b according to the second embodiment, and FIG. 24 shows a cross-sectional view taken along the line AA ′. In addition, the same number is used also in a 2nd embodiment for the part which is common in 1st Embodiment. In the cassette transport system 1a according to the first embodiment, the cassette holding portion 20a is provided at the tip of the second arm 28 of the transfer arms 5a to 5c composed of two arms 24 and 28 that can be bent. In the cassette transport system 1b of the present embodiment, some transfer arms 5d and 5e are configured by a horizontal movable member 19b. As shown in FIG. 24, a cassette holding portion 20a is provided at the upper end of the horizontal movable member 19b, and the other end is connected to the ball screw shaft 22 of the horizontal drive portion. Thereby, when the ball screw shaft is driven to rotate, the horizontal movable member 19b moves in the horizontal direction and conveys the cassette 3.
[0062]
FIG. 6 shows a cassette carrying system 1c according to the third embodiment. As in FIG. 5, the same reference numerals are used in the third embodiment for parts common to the first and second embodiments (the same applies to the following embodiments). The cassette transfer system 1b of FIG. 5 includes transfer arms 5a and 5c including a first arm 24 and a second arm 28 at least at the branch 4 (9), whereas in the cassette transfer system 1c, The transfer arms 5a and 5c having the first and second arms are not present. Instead, transfer arms 5e and 5f are provided. The transfer arms 5e and 5f include a cassette holding arm 85 extending to the main line side in order to deliver the cassette to the main line 4 (7).
The horizontal driving portions 18c and 18d for moving the transfer arms 5e and 5f along the branches 4 (9a) and 4 (9b) are provided below the sides of the branches 4 (9a) and 4 (9b). .
[0063]
FIG. 7 shows a cassette carrying system 1d according to the fourth embodiment. In the cassette carrying system 1d according to the fourth embodiment, each transfer arm 5j, 5k includes a first cassette holding portion 43 and a second cassette holding portion 47 at both ends of the cassette holding arm 86, respectively. Is different. As described above, the first and second cassette holding portions 43 and 47 are provided at both ends of the cassette holding arm 86 extending left and right, and the cassette 3 is formed by the left and right first and second cassette holding portions 43 and 47 on the conveyance path. , The horizontal movement distance of the transfer arms 5j and 5k can be shortened compared to the case where the transfer arms 5e and 5f of FIG. 6 are used.
[0064]
This will be described in comparison with the transfer arm 5f provided at the branch 4 (9b) in FIG. In the embodiment of FIG. 6, the horizontal drive unit 18 d provided on the side of the branch 4 (9 b) extends to the side of the lifting device 10 of the cassette 3. In the embodiment of FIG. 7, the horizontal drive unit 18e does not extend to the side of the lifting device 10, and the horizontal movement distance is shorter than that of the horizontal drive unit 18d of FIG. This is because in the embodiment of FIG. 6, the transfer arm 5 f transfers the cassette 3 to the transfer arm 5 d without taking it back, so that the transfer arm 5 f holds the specific holding recess 44 of the cassette 3. On the other hand, in the transfer arm 5j of FIG. 7, the cassette 3 is temporarily placed on the transport path, and the cassette 3 is transported by being transferred by the left and right cassette holding portions 43 and 47. For this reason, in the case of the embodiment of FIG. 7, the horizontal drive distance of the horizontal drive unit 18e can be shortened as compared with the case where the delivery method without the change of the embodiment of FIG.
[0065]
7 to 10, in the fourth embodiment, the cassette 3 on the lifting device 10 is transported to the position F on the main line 7 of the transport path 4 via the branch path 9 c of the transport path 4. The transport procedure will be described in more detail. 8 and 9 are cross-sectional views showing side portions of the lifting device 10, the transport path 4, and the horizontal drive unit 18e. The cassette 3 is moved by the transfer arm 5j from the lifting device 10 via the branch path 9c of the transport path 4. A state of being conveyed up to the main line 7 is shown. FIG. 10 is a flowchart showing a procedure in which the cassette 3 is transported from the lifting device 10 to the main line 7 by the transfer arm 5j.
[0066]
This will be described with reference to the flowchart of FIG. First, as shown in FIG. 8A, the transfer arm 5j is moved to the position A at the left end of the branch 4 (9c) (S101). Next, the first cassette holder 43 is inserted into the first holding recess 44a provided in the lower part of the cassette 3 on the lifting device 10 (S102). Then, the horizontal drive part 18e is driven and the cassette 3 is moved rightward to the position B shown in FIG. 8b. Next, the cassette pin 46 is raised by the pin lifting device 45 (S104). When the cassette 3 is supported at the predetermined position shown in FIG. 8C by being supported by the pins 46, the holding by the first cassette holding portion 43 is released (S105).
[0067]
Thereafter, as shown in FIG. 9A, the transfer arm 5j is moved to the left position C (S106), and the second cassette holding portion 47 on the opposite side is inserted into the second holding recess 44b. The cassette 3 is held (S107). When the cassette 3 is held, as shown in FIG. 9B, the cassette pin 46 that has locked the cassette 3 is lowered (S108). Next, as shown in FIG. 9C, the transfer arm 5j is further moved to the right until the transfer arm 5k on the main line 4 (7) can hold the cassette 3 (S109). At the same time, the transfer arm 5k is moved to a position E (see FIG. 7) where the cassette 3 can be held by the first cassette holding portion 43 (S110), and the cassette 3 is held by the first cassette holding portion 43 of the transfer arm 5k. (S111). Thereafter, the holding of the cassette 3 by the second cassette holding portion 47 of the transfer arm 5j is released (S112), and the transfer arm 5j is moved to a standby position (for example, position C) (S113). The cassette 3 is conveyed to the position F on the main line 7 by the transfer arm 5k.
[0068]
7 to 9, the height of the cassette holding means is shifted so that the second cassette holding means 47 of the transfer arm 5j and the first cassette holding means 43 of the transfer arm 5k do not collide. Correspondingly, the holding recesses 44a and 44b provided at the lower part of the cassette 3 are elongated vertically extending in the height direction so that the cassette 3 can be held by the cassette holding means of any transfer arm having a different height. It is formed in a groove shape.
[0069]
FIG. 11A is a cross-sectional view showing an example of the shift mechanism 11 provided inside the lifting platform 35 of the lifting device 10, and FIG. 11B is a perspective view thereof. The shift mechanism 11 is a mechanism for changing the orientation of the cassette 3, and is a ring shape that can be rotated on the vertically movable base 49 provided inside the lifting platform 35 and on the center of the lifting platform 35. The mounting table 51 is provided. The mounting table 51 is rotationally driven by a motor 50 fixed to the movable base 49. The vertically movable base 49 is supported by a base lifting device 48 such as an air cylinder capable of slightly lifting the movable base 49 itself upward. By lifting the ring-shaped mounting table 51 by the base lifting device 48, the mounting table 51 protrudes upward from the lifting table 35, and the cassette 3 can be mounted thereon. By rotating the mounting table 51 in this state, the orientation of the cassette 3 can be shifted to a desired direction.
[0070]
On the upper surface of the mounting table 51, a positioning pin 52 is provided for contacting the lower edge of the cassette 3 to position the cassette 3 at a predetermined position. The positioning pin 52 has a substantially conical shape, and the positioning pin 52 is dropped into a hole provided at a predetermined position on the bottom surface of the cassette to position the cassette. Therefore, the upper surface and the side surface of the positioning pin 52 are subjected to surface processing so as to be slippery when the cassette 3 abuts. Further, the shift mechanism 11 includes a compressor (compression pump) 13 and a pressure adjustment chamber 14, and jets high-pressure gas from a hole 16 provided in the ceiling member 14 to float the cassette 3.
[0071]
The operation of adjusting the orientation of the cassette 3 by the shift mechanism 11 will be described with reference to FIG. After the floating cassette 3 is moved onto the lifting device 10 by the cassette transport robot, the base lifting device 48 such as the air cylinder 48 is operated to raise the positioning pin 52. Thereafter, by stopping the compressor 13, the cassette 3 (shown by a broken line) is lowered onto the mounting table 51 of the lifting device 10. At this time, since the mounting table 51 is raised by the base lifting device 48, the upper surface of the mounting table 51 is higher than the upper surface of the ceiling member 15. Therefore, the cassette 3 placed on the placing table 51 can be rotated by operating the motor 50.
[0072]
As described above, when the cassette 3 is placed on the conveyance path or the like, the pins 46 can be lifted while the cassette 3 is floated, and the cassette 3 can be held. Can be suppressed, and damage to the large substrate due to vibration can be prevented.
[0073]
FIG. 14 shows a cassette carrying system 1e according to the fifth embodiment of the present invention. In the fifth embodiment, the mechanism for floating the cassette 3 is greatly different. Whereas the cassette transport systems 1a to 1d of the first to fourth embodiments are provided with the levitation device 6 on the upper surface of the transport path 4, in the fifth embodiment, the levitation device 6e is disposed below the cassette 3e. It differs in the point to prepare for. Thus, the fifth embodiment differs from the first to fourth embodiments in the structure of the cassette and the levitating device, etc., so the number of each part of the cassette and the levitating device etc. of this structure is “3e”, Like "6e", "e" is appended to the number to indicate the first to fourth cassettes 3 separately.
[0074]
The transfer arms 5m to 5p provided in the cassette transport system 1e include a coupler 55 (see FIG. 16) that serves as a connector for supplying gas to the floating device 6e when the protruding member 53e of the cassette holding means 20e holds the cassette 3e. Prepare. The cassette holder 20e will be described later with reference to FIG. The lower portion of the cassette 3e is provided with a concave holding concave portion 44e that comes into contact with the protruding member 53e of the cassette holding portion 20e.
[0075]
In addition, the cassette conveyance system 1e of FIG. 14 replaces the cassette 3 and the conveyance path 4 of FIG. 1 with the cassette 3e provided with the levitation device 6e and the conveyance path 4e without the hole 16 in the ceiling member. Similarly, the transport path 4 and the cassette 3 of the cassette transport systems 1b to 1d according to the second to fourth embodiments can be replaced with the fifth transport path 4e and the cassette 3e.
[0076]
FIG. 15 shows a cassette carrying system 1f according to the sixth embodiment. In the sixth embodiment, the arm of the cassette transfer robot 5q is longer than the transfer arm 5n of the transfer path main line 4e (7) of the cassette transfer system 1e shown in FIG. 14, and the horizontal drive unit as shown in FIG. The difference is that 18a is not provided. That is, as shown in FIG. 15, since the cassette can be transported to a long distance by extending and contracting the long arm of the transfer arm 5p, the horizontal drive unit 18a is not required. The transfer arm 5q having such a long arm can be used for the transport path main line 4 (7) of all the embodiments already described.
[0077]
FIG. 16 is a cross-sectional view showing an example of the structure of the cassette holding means 20e of the transfer arms 5m to 5q according to the fifth and sixth embodiments. In the following description, the cassette holding means 20e of the transfer arm 5n shown in FIG. 14 will be used. A cassette holding means 20e is provided near the tip of the second arm 28 of the transfer arm. The cassette holding means 20e includes a projecting member 53e joined to the cassette 3e, and an air cylinder 48e that is a driving means for projecting the projecting member 53e toward the holding recess 44e of the cassette 3e.
[0078]
The air cylinder 48e is driven by the electromagnetic valve 56a, and high pressure gas is supplied from the compression pump (compressor) 13 through the electromagnetic valve 56a and the pipe 57a by opening the electromagnetic valve 56a. When the air cylinder 48e is driven, the projecting member 53e is linearly driven toward the holding recess 44e (in the direction of the white arrow in the figure) of the cassette 3, thereby inserting the projecting member 53e into the holding recess 44e for connection. To do. The holding recess 44e of the cassette 3e includes a coupler receiver 70 that engages with the coupler 55 when contacting the coupler 55.
[0079]
A coupler 55 for supplying gas to the floating device 6e of the cassette 3e is provided at the tip of the protruding member 53e. A pipe 57b is connected to the coupler 55, and high-pressure gas is supplied to the pipe 57b from the compression pump 13 through another electromagnetic valve 56b.
[0080]
A coupler receiver 70 is provided in the holding recess 44e of the cassette 3e, and the coupler 55 of the protruding member 53e is connected to the coupler receiver 70. The broken line in the drawing shows a state in which the protruding member 53e and the coupler 55 are connected to the holding recess 44e. The high-pressure gas supplied from the coupler receiver 70 is sent to the pressure adjustment chamber 14e of the levitation device 6e (see FIG. 21 (a)), and a flat plate-shaped conveyance path 4e from the jet port provided in the bottom member of the pressure adjustment chamber 14e. Erupted toward. Thereby, the cassette 3e can be levitated. A known technique can be used for the coupler 55 and the coupler receiver 70.
[0081]
It is desirable to provide a pressure sensor 73 in the middle of the pipe 57b. If the coupler 55 is not correctly connected to the coupler receiver 70 due to the cassette holding means 20e failing to hold the cassette 3e, the high-pressure gas does not flow into the pipe 71 of the coupler receiver 70, causing leakage and reducing the pressure. By detecting this pressure drop by the pressure sensor 73, it is possible to determine whether or not the coupler 55 is properly connected.
[0082]
As shown in FIG. 25, it is also possible to provide a coil 86 at the tip circumferential portion of the protruding member 53e and provide a permanent magnet (or a coil) 87 in the cassette 3e. FIG. 25 is a cross-sectional view illustrating an example of the structure of a cassette holding unit 20e according to another embodiment of the transfer arms 5m to 5q according to the fifth and sixth embodiments. With this configuration, when the protruding member 53e is protruded and the coupler 55 is mounted, by passing an electric current through the coil 86, the coil 86 and the permanent magnet 87 are brought into close contact with each other, and the cassette 3e is firmly held by the transfer arm. And a fine positional shift can be prevented.
[0083]
FIG. 17 shows an example of a mini-environment device (highly clean environment maintaining device) 58 that includes the substrate take-out device 12 therein. The substrate take-out device 12 takes out the substrate 2 from the cassette 3e (the same applies to the cassette 3) and transports it to the processing device 8 via the mini-environment device 58. The mini-environment device 58 is a sealed structure that is isolated from the external atmosphere in order to keep the internal atmosphere in a highly clean state. An FFU (fan filter unit) 59 for supplying clean gas to the inside of the apparatus is provided on the upper portion of the mini-environment device 58. Grating (a plurality of holes) is provided from the FFU 59 on the upper portion of the mini-environment device 58. A clean gas is flowing into the floor 60).
[0084]
The mini-environment device 58 is provided between the processing device 8 and the transport path 4e (9a, 9b), and includes a processing device door 61 on the processing device 8, and the transport path 4e (9a, 9b) side. Is provided with a mounting table door 62. The cassette 3e is an accommodation tool that includes an opening 63 (see FIG. 19) on one side surface, and seals the opening 63 with a lid 64 to keep the inside of the cassette clean and accommodate a substrate therein. .
[0085]
The substrate take-out device 12 can be moved in the horizontal direction by the horizontal moving unit 83, and the position in the horizontal direction can be adjusted according to the position where the cassette 3e is placed. The lateral movement unit 83 is implemented by using a mechanism that rotates a ball screw shaft or the like similar to the horizontal drive unit 18a that linearly moves the cassette conveyance robot 5 described above along the conveyance path 4 (7). Is possible.
[0086]
18 and 19 show the cassette 3e when the cassette 3e is placed on the placing table of the conveyance path branch 4e (9b) shown in FIG. 17 and the lid 64 and the placing table side door 62 of the cassette 3e are opened. FIG. 6 is a side view showing the structure and movement of 64 and the mounting table side door 64. The lid 64 of the cassette 3e is removed in the order of FIG. 18 (a) → FIG. 18 (b) → FIG. 19 (a) → FIG. 19 (b).
[0087]
FIG. 20 is a flowchart illustrating an example of a procedure for transporting the substrate 2 in the cassette 3 e to the mini-environment device 58. A procedure for taking out the substrate 2 from the cassette 3e will be described below with reference to FIGS.
[0088]
As shown in FIG. 18A, the cassette 3e floating on the branch path 9b of the transport path 4e is held by the cassette holding portion 20e of the transfer arm 5p. The transfer arm 5p extends the arm to move (advance) the cassette 3e to a predetermined position in order to place the cassette 3e at a predetermined position (S201). The reference numeral 67 in FIGS. 18 and 19 is a latch key receiver for unlocking the lid 64 of the cassette 3, and the reference numeral 68 is a latch key provided on the mounting table side door 64. The latch key 68 is inserted into the latch key receiver 67 to unlock the lid 64.
[0089]
When the cassette 3 is moved to a predetermined position where the mounting table side door 62 and the lid 64 contact each other as shown in FIG. 18B, the transfer arm 5p stops the movement of the arm (S202). At this time, the latch key 68 is inserted into the latch key receiver 67 of the lid 64. Thereafter, by rotating the latch key 68, the mounting table side door 62 and the lid 64 are combined (S203).
[0090]
Thereafter, as shown in FIG. 19A, the cassette 3e is slightly retracted by the transfer arm 5p to remove the lid 64 from the cassette body 65 (S204).
[0091]
Next, as shown in FIG. 19 (b), the door elevating device 66 is operated while the lid 64 and the mounting table side door 62 are combined, and the door 62 is lowered into the lower space, thereby mini The inside of the environment device 58 and the inside of the cassette 3e are communicated (S205). The door elevating device 66 can be configured to perform an elevating operation by a combination of an air cylinder, a motor, a ball screw shaft, a linear motion bearing and the like. Next, the cassette body 65 is further moved inward of the mini-environment device 58 and stopped at a predetermined position (position in FIG. 19b) for substrate delivery (S206).
[0092]
In the mini-environment device 58 of the present invention, a gap of about 2 mm to 10 mm (preferably 5 mm) is provided between the cassette 3e and the opening 72 of the mini-environment device 58. However, since the internal pressure of the mini-environment device 58 of the present invention is set higher than the outside, an air flow from the inside to the outside (the white arrow in the figure) is generated in the gap. Thereby, it is possible to prevent the external cleanliness or air containing dust from flowing into the mini-environment device 58. Further, if the flow rate of this air flow is not sufficient, an air flow that encloses the outside air containing dust may be generated, and the inside of the apparatus may be contaminated. The reason why the cassette 3 is moved forward in the above-described step S206 is that the cassette 3e is moved to the inside of the mini-environment device 58 so that the cassette 3e is less affected by the airflow including the dust near the gap. It is. Further, by moving to the back in this way, the air flow from the inside of the apparatus toward the gap easily circulates inside the cassette 3 and tends to generate a downward air flow, whereby the inside of the cassette 3 can be kept highly clean.
[0093]
In the above-described example, the lid 64 is removed from the cassette body 65 by slightly retracting the cassette body 65, but it is also possible to move the mounting table side door 62 to the inside. However, it should be noted that this method brings the lid 64 to which dust is attached to a highly clean area, which may cause contamination inside the apparatus.
[0094]
FIG. 21 is a perspective view of the cassette 3e including the levitation device 6e as viewed from the bottom. Reference numeral 65 shown in FIG. 21A denotes a cassette body, which is usually sealed with a lid 64. A plurality of substrates 2 are stored at predetermined intervals on a shelf (not shown) inside the cassette body 65. A levitation device 6 e is provided below the cassette body 65. The levitation device 6e includes a coupler receiver 70 for connecting a coupler 55 that supplies compressed high-pressure gas, four pressure adjustment chambers 14e, and a cassette pipe 71 that sends the high-pressure gas to the four pressure adjustment chambers 14e. ing. A large number of ejection holes 16e are provided at the bottom of the pressure adjusting chamber 14e, and the cassette 3 is floated by ejecting high-pressure gas downward from the ejection ports 16e on the back surface of the cassette 3e.
[0095]
There may be only one pressure adjusting chamber 14e, but when there is unevenness on the transfer path 4 and it is not flat, etc., gas jets due to the difference in the distance (gap) between the jet outlet 16e and the transfer path surface Unevenness occurs. There is a possibility that the back surface of the cassette 3 rubs the transport path 4e at a short distance. In order to minimize such a possibility, in this embodiment, the pressure adjusting chamber 14e is divided into four so that gas can be ejected in a stable state. It is possible to further divide the pressure adjusting chamber 14e into two or three pressure adjusting chambers.
[0096]
FIG. 21B shows a cassette 3f according to another embodiment. In the levitating device 6f of the cassette 3f, the shape of the pressure adjusting chamber 14f is a large cylindrical shape having a ceiling portion, and the bottom side of the cassette 3f is open. In addition, the coupler 55 and the like are the same as those in FIG.
[0097]
FIG. 22 is a cross-sectional view showing an example of the coupler 55 and the coupler receiver 70. A coupler 55 for connecting to the levitation devices 6e and 6f is provided at the tip of the supply unit that supplies gas from a pump (not shown). FIG. 22A shows a state before the coupler 55 and the coupler receiver 70 come into contact with each other. By inserting the coupler 55 into a coupler receiver 70 provided in the levitation devices 6e and 6f, both are connected. FIG. 22B shows a state where the coupler 55 is slightly moved from the state of FIG. 22B and the coupler 55 is in contact with the coupler receiver 70. The coupler 55 is provided with a valve member 75 provided via an elastic member 74 that presses in the lateral direction. A seal member 77 is provided on the outer periphery of the valve member 75 to prevent gas from leaking from the coupler 55 when the valve member 75 comes into contact with the valve member receiver 76 fixed to the inner wall of the coupler receiver 70 body. is doing.
[0098]
FIG. 22C shows a state where the coupler 55 is further inserted into the coupler receiver 70 and is completely connected. The elastic member 74 between the coupler main body 78 and the valve member 75 is pressed and contracted, and the coupler main body 78 is provided between the inner wall of the coupler receiving main body 79 and the movable valve member 80 in contact with the inner wall. By compressing 74, the coupler 55 and the coupler receiver 70 can be connected so as to be able to communicate with each other.
[0099]
The coupler 55 will be described below with reference to FIG. The coupler main body 78 is for discharging high-pressure gas supplied through the pipe 57 to the outside. The valve member 75 is a valve for preventing gas from being released from the coupler main body 75 when the coupler 55 is not coupled to the coupler receiver 70. The coupler main body 78 has a cylindrical shape with a bottom, and a pipe 57 for delivering high-pressure gas is attached. The valve member 75 is attached to the inside of the coupler main body 78 with one end thereof being pressed forward by the elastic member 74a. Thereby, the front-end | tip of the valve member 75 is pressed by the opening part of this coupler main-body part 78, plugs the exit part of the piping 57, and has played the role of the valve. In a state where the coupler 55 is not coupled, the valve member 75 and the coupler main body 78 are attached to the valve member 75 and airtightness is maintained by the seal member 77a.
[0100]
In the coupler receiver 70, when the coupler 55 is inserted, the movable valve member 80 is configured to be movable to the left and right inside the coupler receiver main body 79 and outside the valve member receiver 76. Plays. The movable valve member 80 is attached to the valve member receiver 76 while being pressed outward via an elastic member 74b. As a result, when the coupler 55 is not connected, the movable valve member 80 is pressed outward and is in contact with both the coupler receiver 70 and the valve member receiver 76, and the seal member 77 b attached to the valve member receiver 76 is used. The movable valve member 80 and the valve member receiver 76 are kept airtight.
[0101]
A state in which the coupler 55 and the coupler receiver 70 are inserted and the high-pressure gas is supplied will be described below. FIG. 22B shows a state where the protruding member 53 is slightly moved from the state of FIG. 22A to the cassette 3 side and the coupler main body 78 and the tip of the movable valve member 80 are brought into contact with each other. The coupler body 78 is partially inserted into the coupler receiver body 79. Since the distal end of the coupler main body 78 has a convex shape and the distal end of the movable valve member 80 has a concave shape, they are fitted to each other.
[0102]
Note that a seal member 77c is attached to the movable valve member 80 at a position where it comes into contact with the coupler main body 78, thereby maintaining the airtightness of both contact portions at the time of contact. In FIG. 22B, the movable valve member 75 and the valve member receiver 76 are in contact with each other, but at this time, the inside of the coupler body 78 and the inside of the movable valve member 80 are not in communication (coupler body 78). The elastic member 74a provided in the inside of the movable valve member 80 and the elastic member 74b provided in the movable valve member 80 are not shrunk from the state shown in FIG.
[0103]
FIG. 22 (c) shows a state in which the protruding member 53 is further inserted further into the holding recess 44e of the cassette 3e and is coupled. The coupler main body 78 pushes and moves the movable valve member 80 to the left, so that the elastic member 74b provided between the movable valve member 80 and the valve member receiver 76 is compressed. Note that the airtightness of the movable valve member 80 and the valve member receiver 76 is maintained by a seal member 77d provided outside the valve member receiver 76.
[0104]
Further, when the protruding member 53 is inserted into the back, the valve member 75 is pressed by the tip of the valve member receiver 76, so that the elastic member 74a provided between the valve member 75 and the coupler main body 78 is compressed. It becomes a state. As a result, the valve functions of both the valve member 75 and the movable valve member 80 are released, and the gas supplied from the pipe 57 passes through the inside of the coupler main body 78 and communicates with the interior of the movable valve member (valve. It passes through the outer periphery of the member 75 and the outer peripheral portion of the valve member receiver 76, and flows into the pipe 71 provided inside the valve member 80 through the hole 84 provided in the valve member receiver 80.
[0105]
When the coupler 55 is completely inserted into the coupler receiver 70, the fixing member 81 provided in the coupler receiver main body 79 is locked by fitting into the recess 82 provided in the outer portion of the coupler main body 78. As a result, even if a light force is applied in the direction of pulling out the coupler 55 from the coupler receiver 70, it cannot be easily pulled out.
When removing the coupler receiver 70 from the coupler 55, the fixing member 81 may have a simple locking mechanism using an electromagnetic magnet or an elastic member so that the fixing member 81 can be easily removed by removing it from the recess 82.
[0106]
FIG. 23 is a cross-sectional view illustrating an example of the cassette 3e and the levitating device 6e provided below the cassette 3e. This levitation device 6e has a flow rate Q from the compression pump 13 through a pipe 57 in the transfer arm. _A Of high pressure gas.
[0107]
Now, the flow rate q from the m holes on the bottom surface of the levitation means 6e provided at the bottom of the cassette 3e. _n If (n = 1, 2, 3,... M) gas is ejected, to eject gas from m holes evenly, Q _A ≧ q ₁ + Q ₂ + Q ₃ … + Q _n The diameter of the pump and the pipe 57, the area of the hole (a ₁ + A ₂ + A ₃ ... + a _n ) Must be selected. Note that the buoyancy F caused by the high-pressure gas ejected from the lower portion of the cassette 3 is the gas density ρ (air: ρ = 1.929 [kg / cm ³ ], Flow rate Q (q ₁ + Q ₂ + Q ₃ … + Q _n [M ³ / S ² ], Flow velocity v = Q / A [m / s ² ] F = ρ × Q × v [kg · m / s ² ]. The levitation device 6 needs to output buoyancy according to the weight of the cassette 3.
[0108]
FIG. 26 is a cross-sectional view illustrating another embodiment of the cassette 3e and the levitating device provided in the lower portion of the cassette 3e. As shown in FIG. 26, even if the cassette is not hermetically sealed, the inside of the substrate storage space is always cleaned by depressurizing a part of the clean high-pressure gas from the transfer arm tip 20e into the cassette body 65. Can be kept in. The clean gas is blown out from the outlet 88 through the pipe in the cassette body 65 via the coupler 55, and is discharged from the outlet 97 to the outside of the cassette through the inlet 89. At this time, clean gas is supplied into the cassette main body 65 from the distal ends 20e of the left and right transfer arms so that the pressure in the left and right pressure adjusting chambers 14e is uniform, and an exhaust port (not shown) is provided at the bottom of the cassette. May be provided.
[0109]
FIG. 27 is a cross-sectional view of the conveyance path 4 and the cassette 3e for explaining a structure in which the cassette is stopped in a floating state. A permanent magnet 98 can be provided on the bottom surface of the cassette 3e, and a stop coil 99 can be provided that generates a magnetic field by flowing a current to the cassette stop position on the top surface of the transport path. As a result, when the cassette 3e passes through the stop position, an electric current is passed through the stop coil 99, and the permanent magnet 98 is attracted by a magnetic force, so that the cassette 3e can be kept in the stopped state while being floated. . The cassette 3e can be stopped while floating and the transfer arm can be transferred, and the transfer can be started immediately after the transfer is completed. Although it is possible to provide a stop mechanism by a mechanism such as a stop arm, the stop mechanism is complicated and large, and there is a possibility that the foot space becomes a problem. On the other hand, the permanent magnet 98 and the stop coil 93 are simple in structure and low in cost. Another advantage is that no extra foot space is required. If the permanent magnet 98 is provided at the bottom of the cassette 3e, there is a possibility that dust such as iron powder may be picked up. Therefore, a magnetic body 98 such as iron can be used instead of the permanent magnet. In this case, it is desirable to employ a light magnetic material. It is also possible to provide a permanent magnet or magnetic body 98 on the side of the bottom of the cassette 3e and provide a stop coil 93 on the side wall of the transport path.
[0110]
As described above, in the cassette transport system of the present invention, the cassette is lifted and moved, so that the drive output for driving the cassette in the lateral direction can be reduced, and the cassette transport system can be downsized. It becomes possible. Further, in the cassette transport system of the present invention, the cassette is levitated by blowing gas over the entire bottom surface of the cassette or by ejecting gas from the entire bottom surface of the cassette. There is no concentrated load on a part of the bottom. That is, since the entire bottom surface is lifted by the floating means, the cassette itself does not bend. Therefore, unlike lifting with a lift, there is no inconvenience such as a gap even if a heavy cassette is sealed with a lid. Further, no special design such as increasing the rigidity of the cassette is required to suppress the bending.
[0111]
In the cassette conveying system of the present invention, the conveying path and the cassette can be moved without contact by the levitation means, so that generation of dust such as particles due to sliding friction can be suppressed.
[0112]
On the other hand, when the transfer arm is used for horizontal transfer movement, since the cassette is always held by the transfer arm, it is possible to prevent lateral displacement due to external force. In addition, the inertial force that accompanies the movement increases as the cassette becomes heavier, but since the cassette is firmly held by the transfer arm, the inertial force can be accurately controlled and accurately transported to the desired position. Can be stopped. This makes it possible to accurately position a heavy cassette that is heavy on the load port. Further, as described above, suppression of vibration is particularly important in a large-sized substrate, but it is possible to reduce minute vibration caused by the jet gas by holding it with an arm.
[0113]
Further, when the cassette is sequentially transferred and transported by the transfer arm, a plurality of cassettes can be transported simultaneously on one transport path. In addition, by providing a branch in the transport path, the cassette can be temporarily retracted in the branch or at the end of the transport path in an emergency. As a result, in order to process an urgent lot, one of the production lines in use can be opened as an emergency lot processing line.
[0114]
This specification is based on Japanese Patent Application No. 2005-125765 for which it applied on April 22, 2005, and Japanese Patent Application No. 2005-178630 for which it applied on June 17, 2005. All this content is included here.

Claims (13)

In a clean environment, a cassette transport system that transports a large cassette that accommodates a large transport object therein to a desired position along a predetermined transport path,
A levitation device comprising: a compression unit that compresses gas to generate high-pressure gas; and an ejection unit that ejects the compressed high-pressure gas from a plurality of ejection ports, and the cassette floats on the transport path by ejection of the high-pressure gas. ,
A cassette transfer comprising at least one transfer arm capable of holding and releasing the cassette, and transferring the transfer arm in a horizontal direction along the transfer path in a state where the floated cassette is held by the transfer arm. Equipment,
A transport control device for controlling ejection of gas by the levitation device and transport of the cassette by the cassette transport device, and transporting the cassette to a target position;
A cassette carrying system comprising:   At least one of the transfer arms has at least two arm members linked to each other, and the cassette held at the tip of the transfer arm by driving the two or more arm members to bend and extend by the link coupling portion. The cassette conveying system according to claim 1, wherein the cassette is transported in a horizontal direction.   The cassette transport system according to claim 1, wherein at least one of the transfer arms includes a horizontal moving unit that horizontally moves along the transport path while holding the cassette.   The cassette transfer system according to claim 1, wherein the transfer arm of the cassette transfer device is provided on both sides of the transfer path along the transfer path.   In the levitation device, the ejection portion is provided on an upper surface of the conveyance path, and the cassette placed on the conveyance path is levitated by ejecting high-pressure gas upward from the ejection portion. The cassette carrying system according to any one of claims 1 to 4. The levitation device is configured such that the ejection portion is divided and arranged in predetermined units along the conveyance path, and the high-pressure gas can be ejected for each divided unit.
The cassette transport system according to claim 5, wherein the transport control device controls to sequentially switch a jet position of the high-pressure gas of the levitation device in accordance with a moving position of the cassette on the transport path. The cassette transfer device includes a plurality of transfer arms along the transfer path, and moves the transfer arm in the horizontal direction along the transfer path in a state where the floated cassette is held by the transfer arm. 6. The cassette transfer system according to claim 5 , wherein the cassette is transferred to a target position by delivering the cassette while being floated to another adjacent transfer arm.   The jetting portion of the levitation device is provided on a lower surface of the cassette, and the cassette is floated by jetting high-pressure gas from the jetting portion to the transport path. 2. A cassette conveying system according to claim 1.   The levitation device supplies high-pressure gas from the compression unit to the injection unit provided in the lower part of the cassette via a pipe provided in the transfer arm and a holding unit for holding the cassette. 9. The cassette carrying system according to claim 8, wherein   The cassette transfer device includes a plurality of transfer arms along the transfer path, and moves the transfer arm in the horizontal direction along the transfer path in a state where the floated cassette is held by the transfer arm. The cassette transport system according to claim 9, wherein the cassette is transferred to a target position by delivering the cassette while being floated to another adjacent transfer arm.   The cassette transport according to claim 10, wherein the transport control device controls to sequentially switch the transfer arm that supplies the high-pressure gas from the compression unit in response to the transfer of the cassette by the transfer arm. system.   The said conveyance path is provided with one main line and the crossroad extended at a predetermined angle from the said main line, The said transfer arm is provided in each of the said main line and a crossroad, The one of the Claims 1 thru | or 4 characterized by the above-mentioned. 2. The cassette conveyance system according to item 1.   The elevating device for placing and lifting the cassette on any one of the conveying paths is provided, and the elevating device comprises the levitation device on a placing table on which the cassette is placed. The cassette conveyance system of any one of 1-4.

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