JP2012190832A - Conveyance system, and manufacturing method of device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a conveyance system which is advantageous for conveying an original plate quickly in safety.SOLUTION: The conveyance system 1 comprises at least one exposure device 2 which exposes a pattern formed on an original plate 3 to a substrate, a transport vehicle 4 which holds and transports the original plate 3 to the exposure device 2, and a travel path 5 on which the transport vehicle 4 travels. The height from a surface on which the exposure device 2 is laid to the carry-in port 9 through which the original plate 3 installed on the exposure device 2 is carried in is higher than the height from the surface on which the transport vehicle 4 travels to the holding position of the original plate 3 when the transport vehicle 4 travels while holding the original plate 3. The holding position of the transport vehicle 4 matches the position where the exposure device 2 receives the original plate 3 from the carry-in port 9.

Description

  The present invention relates to a transport system and a device manufacturing method using the transport system.

  Conventionally, in a manufacturing process of a semiconductor device, a liquid crystal display device or the like, there is a lithography process in which a fine pattern is transferred to a substrate by an exposure apparatus or the like. For example, the exposure apparatus is an apparatus that transfers a pattern of an original (a mask or a reticle) to a photosensitive substrate (a glass plate or a wafer having a resist layer formed on the surface) via a projection optical system. In this lithography process, the original is appropriately transported to one or a plurality of exposure apparatuses in a clean room. Examples of the original plate transfer method include manual transfer by an operator himself, automatic transfer by an unattended automatic transfer system, and the like. Here, since the conveyance of the original plate by manual conveyance has become difficult with the increase in size or weight, in recent years, the conveyance of the original plate by the unmanned automatic conveyance system has become mainstream.

  As this unmanned automatic conveyance system, for example, Patent Document 1 discloses an unmanned conveyance apparatus employing AGV (Automated Guided Vehicle) or RGV (Rail Guided Vehicle). In particular, this automatic transfer device is equipped with a vertical drive mechanism for adjusting the height at which a container containing a workpiece is transferred to the device manufacturing apparatus. Patent Document 2 discloses an automatic guided vehicle that employs an industrial manipulator for such a vertical drive mechanism.

JP 2001-354302 A Japanese Patent Laid-Open No. 10-194445

  In general, in the exposure apparatus, the original entrance is installed at a relatively high position on the projection optical system. Therefore, when the original is transported to the exposure apparatus, an AGV equipped with an up-and-down drive mechanism that can move the original also in the vertical direction (height direction) with respect to the carry-in entrance as shown in Patent Documents 1 and 2. It is necessary to adopt RGV. However, since such AGV and RGV are provided with a vertical drive mechanism in addition to a normal steering mechanism, the structure is complicated and the cost is increased. Moreover, since normal AGV and RGV move (operate) on the same floor surface where an operator walks, they operate at a low speed. Therefore, depending on the replacement frequency of the original plate, it is necessary to increase the number of AGVs and RGVs for operation.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a transport system that is advantageous for transporting an original quickly and safely.

  In order to solve the above-described problems, the present invention provides at least one exposure apparatus that exposes a pattern formed on an original on a substrate, a transport vehicle that holds the original and transports it to the exposure apparatus, and travel that the transport vehicle travels. A transport system having a road, the height from the surface on which the exposure apparatus is laid down to the carry-in entrance for carrying the original plate installed in the exposure apparatus is determined from the surface on which the transport vehicle travels. It is higher than the height to the holding position of the original when traveling while being held, and the holding position of the transport vehicle coincides with the position where the exposure apparatus receives the original from the carry-in entrance.

  According to the present invention, it is possible to provide a transport system that is advantageous for transporting an original plate quickly and safely.

It is a figure which shows the structure of the conveyance system which concerns on 1st Embodiment of this invention. It is a figure which shows the structure of an exposure process part. It is a figure which shows the structure of the conveyance system which is a modification of 1st Embodiment. It is a figure which shows the structure of the conveyance system which concerns on 2nd Embodiment of this invention. It is a figure which shows the structure of the conventional conveyance system.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a diagram showing a configuration of a transport system 1 according to the first embodiment of the present invention. Hereinafter, the transport system 1 is used in a liquid crystal display device production line, and will be described as transporting a mask (original) 3 to the exposure apparatus 2 in a lithography process. However, the transport system 1 is not limited to an exposure apparatus that manufactures a liquid crystal display device, but can also be used in, for example, an exposure apparatus that manufactures semiconductor devices. The transport system 1 includes an automatic guided vehicle 4 that transports a mask 3 to at least one exposure apparatus 2 laid in a clean room in a device manufacturing factory, and a traveling path 5 of the automatic guided vehicle 4. In each of the following drawings, the Z axis is taken in the laying direction (vertical direction) of the exposure apparatus 2, and the Y axis is in one of the traveling directions (horizontal direction) of the automatic guided vehicle 4 in a plane perpendicular to the Z axis. And taking the X axis in another direction orthogonal to the Y axis.

  FIG. 1A is a side view showing an exposure apparatus 2 laid in a clean room and a part of a traveling path 5 provided adjacent to the exposure apparatus 2. The exposure apparatus 2 projects and transfers a pattern (for example, a TFT circuit) formed on the mask 3 onto a substrate coated with a photosensitive agent. In the present embodiment, a mirror scan type configuration is used as an example. Shall have. In addition, as shown in FIG. 1A, the exposure apparatus 2 is provided with a coating and developing apparatus 6 for performing application of a photosensitive agent to the substrate, development of the exposed substrate, and the like. A transfer station 7 having an apparatus 8 for transferring a substrate is installed between the exposure apparatus 2 and the exposure apparatus 2. However, regarding the present invention, the configurations of the coating and developing apparatus 6 and the transport station 7 are not essential, and thus the description thereof is omitted.

  FIG. 1B is a plan view showing two exposure apparatuses 2 and a traveling path 5 provided adjacent to the exposure apparatus 2 as an example. The exposure apparatus 2 includes an exposure processing unit 2a that performs an exposure process on the substrate to be processed, a temperature control unit 2b that faces the traveling path 5, and performs temperature control in the space of the exposure processing unit 2a, and an exposure unit. And a mask loading / unloading section 2c for loading / unloading the mask 3 into / from the processing section 2a.

  FIG. 2 is a schematic diagram showing the configuration of the exposure processing unit 2a. The exposure processing unit 2a includes an illumination optical system 21 including a light source 20, a mask stage (original stage) 22 on which the mask 3 is placed, a projection optical system 23, and a substrate stage 24 on which the substrate 14 is placed. The illumination optical system 21 condenses the light beam L on the mask 3 via an internal optical element. The light source 20 emits a light beam L that is exposure light, and is composed of an ultra-high pressure mercury lamp or the like. The mask stage 22 holds the mask 3 and can move in the XY directions. The projection optical system 23 includes a reflecting mirror 25 and a concave mirror 26 inside, and forms a pattern image drawn on the irradiation area of the mask 3 on the substrate 14 while changing the polarization characteristics by the reflecting mirror 25. The projection optical system 23 is installed between the illumination optical system 21 and the mask 3, and forms an image of illumination light that illuminates the alignment mark from the alignment scope 27 having the polarization characteristic optical element on the substrate 14. Further, the substrate stage 24 holds the substrate 14 and can move in the three-dimensional directions of XYZ. Here, the mask 3 held on the mask stage 22 and the substrate 14 held on the substrate stage 24 are arranged in a conjugate positional relationship via the projection optical system 23. Although not shown, the control unit that manages the operation and processing of the exposure apparatus 2 moves the mask 3 and the substrate 14 in synchronization during the exposure process, and moves the pattern formed on the mask 3. A scanning exposure sequence for transferring to the substrate 14 is executed.

  FIG. 1C is a side view of the exposure apparatus 2 and a part of the traveling path 5 provided adjacent to the exposure apparatus 2 as seen from the Y direction. The mask carry-in / out unit 2c is installed on the side surface of the exposure apparatus 2 when the installation position of the exposure processing unit 2a is the front part of the exposure apparatus 2, and receives the mask 3 carried in from the carry-in port 9 in the mask stage. A mask loader (conveying mechanism) 10 that conveys the film 22 is provided. In particular, in this embodiment, the height from the floor surface 11 on which the exposure apparatus 2 is laid to the carry-in entrance 9 is equal to the height from the floor surface 11 to the mask stage 22. Specifically, the height to the carry-in entrance 9 indicates the height to the position where the mask loader 10 receives the mask 3 from the automatic guided vehicle 4. On the other hand, the height to the mask stage 22 indicates the height to the stage surface when the mask stage 22 is in a state of holding the mask 3. That is, the mask loader 10 can transport the mask 3 only by driving in the X direction (or Y direction) without driving in the Z direction. However, the mask carry-in / out unit 2c may include a storage unit (mask stocker) 12 that temporarily stores one or a plurality of masks 3 until an exposure process using the mask 3 is performed.

  Although not shown, the automatic guided vehicle (conveyed vehicle) 4 is a steering mechanism that enables unmanned operation along the reference line R on the travel path 5 and an instruction from the control unit of the transport system 1 or the exposure apparatus 2. And a communication unit that transmits and receives position information of the traveling path 5 and a transfer mechanism for transferring the mask 3. The automatic guided vehicle 4 always keeps the holding position for holding the mask 3 during traveling and the position for delivering the mask 3 at the carry-in port 9 of the exposure apparatus 2 constant. That is, the automatic guided vehicle 4 does not have a vertical drive mechanism (elevating mechanism) that raises the mask 3 to the height of the carry-in entrance 9.

  The traveling path 5 includes a main traveling unit 5a positioned in front of the front portions of the two exposure apparatuses 2, and a sub traveling unit 5b extending from the main traveling unit 5a to the carry-in entrance 9 of each exposure apparatus 2. In the example of FIG. 1, the main traveling unit 5a extends in the X direction, while the auxiliary traveling unit 5b extends in the Y direction. As shown in FIG. 1 (b), the main traveling unit 5a stores a plurality of masks 3 before or after use, and among them, a storage device (main Stocker 13). In addition, the traveling path 5 is installed at a high position while having a space in the Z direction, not the floor surface 11 on which the exposure apparatus 2 is laid. Here, the height from the floor surface 11 to the travel path 5 is determined between the transfer portion (holding position) of the mask 3 of the automatic guided vehicle 4 and the entrance 9 of the mask carry-in / out portion 2c that receives the transferred mask 3. It is set on the basis that the height matches. Further, the auxiliary traveling path 5b has a stepped portion 5c at its end so that the operator W can go up on the traveling path 5, for example, during maintenance.

  Next, conveyance of the mask 3 by the conveyance system 1 will be described. First, a conventional transfer system will be described for comparison with the transfer system 1 of the present embodiment. FIGS. 5A to 5C are diagrams showing a configuration of a conventional transfer system 100 with respect to the configuration of the transfer system 1 shown in each drawing of FIG. In the transport system 100, a control unit (not shown) first transmits a transport instruction to the automatic guided vehicle 101 by wireless communication. Next, the automatic guided vehicle 101 receives the transport instruction, and is in the vicinity of the carry-in entrance 105 of the mask carry-in / out section 102b of the exposure apparatus 102 designated along the reference line R ′ on the floor surface 103 around the exposure apparatus 102. The mask 106 is transported to the end. Next, the automatic guided vehicle 101 communicates with the exposure apparatus 102 via a light transmission means or a wire line about whether or not the mask 106 can be received at the carry-in entrance 105. Here, when the automatic guided vehicle 101 determines that delivery is possible, the mask 106 is exposed from the automatic guided vehicle 101 side by a delivery mechanism mounted on the automatic guided vehicle 101 or a receiving mechanism installed in the exposure apparatus 102. Move to the device 102 side. The mask 106 carried into the exposure apparatus 102 is transferred to a storage unit (mask stocker) 107 installed inside the mask carry-in / out unit 102b and temporarily stored until the exposure process is performed. In this way, in the transport system 100, the travel path (reference line R ′) of the automatic guided vehicle 101 is the same surface as the floor surface on which the exposure apparatus 102 is laid. This is the same space where the worker W walks and works with respect to the exposure apparatus 102. Therefore, the moving speed of the automatic guided vehicle 101 is limited to be equal to or lower than the walking speed of the worker from the viewpoint of safety. Further, depending on the height of the carry-in port 105 of the mask 106 installed in the exposure apparatus 102, the automatic guided vehicle 101 extends in the Z direction as the mask 106 delivery mechanism and raises the mask 106 to the height of the carry-in port 105. It is necessary to provide the vertical drive mechanism 108 to be operated.

  Further, in the transport system 100, the storage unit 107 stores the transferred mask 106 in a dedicated cassette or supplies air to the storage unit inside the storage unit 107, so that foreign matter or the like adheres to the mask 106. To prevent you from doing. In addition, the storage unit 107 can store a plurality of masks 106 with an interval in the Z direction, and includes a lifting mechanism (not shown) that can move the plurality of arranged masks 106 to an appropriate loading / unloading position. . In this case, the control unit of the exposure apparatus 102 first determines the mask 106 to be used for the exposure process, and then drives the lifting mechanism inside the storage unit 107 to deliver the designated mask 106 to the mask loader 109. Move to position. Next, the control unit moves the mask 106 by the mask loader 109 and transfers it to the mask stage 22. Note that when the mask 106 is collected from the mask stage 22, the control unit carries out transport in the reverse order.

  Furthermore, once the exposure processing starts, the exposure apparatus 102 appropriately replaces the mask 106 in addition to replacing the substrate 14. In particular, when the mask 106 is replaced, the exposure apparatus 102 needs to temporarily stop the exposure process, and therefore it is desirable that the replacement time of the mask 106 be as short as possible. For example, in the replacement process of the mask 106, the process of preparing the second mask to be used next is replaced with the first mask held on the mask stage 22 in accordance with the next exposure process. There is a process to do. However, since the automatic guided vehicle 101 has a low moving speed, the second mask cannot be transferred in time after receiving the second mask transfer request. Therefore, conventionally, many masks 106 are previously stored in the storage unit 107 in the mask carry-in / out unit 102b.

  On the other hand, as shown in FIG. 1A, the automatic guided vehicle 4 of the present embodiment travels on a traveling path 5 installed at a position higher in the Z direction than the floor surface 11 on which the exposure apparatus 2 is laid. To do. Since the height position of the traveling path 5 is set in advance so that the height of the transfer portion of the mask 3 of the automatic guided vehicle 4 and the entrance 9 of the mask loading / unloading portion 2c that receives the mask 3 coincide with each other. The automatic guided vehicle 4 does not need to be equipped with a mechanism such as the vertical drive mechanism 108. Therefore, the structure of the automatic guided vehicle 4 can be simplified and reduced in weight, and the cost can be suppressed.

  Further, since the automatic guided vehicle 4 travels on the traveling path 5 installed separately from the floor surface 11 that is a walking path of the worker W who works on the exposure apparatus 2, the traveling speed can be increased. That is, the automatic guided vehicle 4 needs to store a large number of masks 3 in advance in the storage unit 12 in the mask loading / unloading unit 2c because the second mask can be transferred in time even after receiving the second mask transfer request. There is no. Therefore, as shown in FIG. 1C, the number of stocks of the mask 3 in the storage unit 12 can be reduced. Conventionally, the number of the automatic guided vehicles 101 is increased according to the replacement frequency of the mask 106. However, in the transport system 1, the number of the automatic guided vehicles 4 can be reduced as compared with the prior art. 3 can be centrally managed.

  Here, in the exposure processing unit 2a constituting the exposure apparatus 2, the projection optical system 23 is particularly large corresponding to the large substrate 14, as shown in FIG. That is, the height of the mask stage 22 positioned on the projection optical system 23 is much higher than the height of the transfer portion of the mask 3 of the automatic guided vehicle 4 when the automatic guided vehicle 4 is assumed to travel on the floor 11. Very expensive. Therefore, if the height position of the carry-in port 9 of the mask carry-in / out part 2c is the same as the height position of the mask stage 22, the structure of the transport mechanism from the receipt of the mask 3 to the placement on the mask stage 22 is further increased. The mask 3 can be moved more quickly. Further, as described above, the traveling path 5 is installed such that the height of the transfer part of the mask 3 of the automatic guided vehicle 4 and the carry-in entrance 9 of the mask carry-in / out part 2c coincide. For example, the installation height of the travel path 5 is about 2 m when referring to the height of the carry-in entrance 9 of the general exposure apparatus 2. Therefore, even if the traveling path 5 is installed as in the present embodiment, the operator W for the exposure apparatus 2 can freely walk in the space below the traveling path 5 and does not hinder the work.

  As described above, according to the present embodiment, it is advantageous to transport the mask 3 quickly and safely. Note that the transfer system 1 of the present embodiment, for example, as shown in FIGS. 3A and 3B, does not install the mask carry-in / out unit 2 c in the exposure apparatus 2, and performs exposure processing from the carry-in entrance 9. There may be a configuration in which the mask 3 is directly transferred onto the mask stage 22 of the portion 2a. In this case, the exposure apparatus 2 only needs to install the mask loader 110 and, in some cases, the storage 111 that temporarily holds the mask 3 in the transport path of the mask loader 110 in the exposure processing unit 2a. As a result, the overall size of the exposure apparatus 2 is reduced, and the apparatus configuration can be simplified and the cost can be reduced.

(Second Embodiment)
Next, a transport system according to a second embodiment of the present invention will be described. FIG. 4 is a side view showing the configuration of the transport system 40 of the present embodiment corresponding to the transport system 1 according to the first embodiment shown in FIG. In FIG. 4, the same components as those in FIG. The transport system 40 is characterized in that the surface on which the exposure apparatus 2 is laid is not a normal floor surface 11 but a floor lower surface 41 that is one level lower, and a height from the floor surface 11 to the entrance 9 of the mask loading / unloading unit 2c. The point is to lower the height. In FIG. 4, for the sake of convenience, the exposure apparatus 2 and the transfer station 7 are lowered to the floor lower surface 41, and the coating and developing apparatus 6 remains laid on the floor surface 11 as in the first embodiment. There is no particular limitation. According to this configuration, the automatic guided vehicle 4 moves on the floor 11 which is a worker's walking path as a traveling path. However, depending on the device manufacturing process, traveling of the automatic guided vehicle and the walking of the worker may not be performed in parallel on the transport system. Therefore, if the laying surface of the exposure apparatus 2 is lowered so that the height of the transfer portion of the mask 3 of the automatic guided vehicle 4 and the carry-in entrance 9 of the mask carry-in / out portion 2c coincide, There is no need to install the vertical drive mechanism 108 as described above. In general, there is an empty space below the floor 11 where the exposure apparatus 2 is laid, where wiring and piping necessary for a clean room environment are routed. According to this embodiment, a space in a clean room environment such as this empty space can be used effectively.

(Device manufacturing method)
Next, a method for manufacturing a device (semiconductor device, liquid crystal display device, etc.) according to an embodiment of the present invention will be described. A semiconductor device is manufactured through a pre-process for producing an integrated circuit on a wafer and a post-process for completing an integrated circuit chip on the wafer produced in the pre-process as a product. The pre-process includes a step of exposing a wafer coated with a photosensitive agent using the above-described exposure apparatus, and a step of developing the wafer. The post-process includes an assembly process (dicing and bonding) and a packaging process (encapsulation). A liquid crystal display device is manufactured through a process of forming a transparent electrode. The step of forming the transparent electrode includes a step of applying a photosensitive agent to a glass substrate on which a transparent conductive film is deposited, a step of exposing the glass substrate on which the photosensitive agent is applied using the above-described exposure apparatus, and a glass substrate. The process of developing is included. According to the device manufacturing method of the present embodiment, it is possible to manufacture a higher quality device than before.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to these embodiment, A various deformation | transformation and change are possible within the range of the summary.

DESCRIPTION OF SYMBOLS 1 Transfer system 2 Exposure apparatus 3 Mask 4 Automatic guided vehicle 5 Traveling path 9 Carriage entrance

Claims (6)

A transport system having at least one exposure device that exposes a pattern formed on an original plate onto a substrate, a transport vehicle that holds the original plate and transports it to the exposure device, and a travel path on which the transport vehicle travels,
The height from the surface on which the exposure apparatus is laid down to the carry-in entrance for carrying the original plate installed in the exposure apparatus is from the surface on which the transport vehicle travels, and the transport vehicle travels while holding the original plate. Higher than the height to the holding position of the original when
The transport system according to claim 1, wherein the holding position of the transport vehicle coincides with a position at which the exposure apparatus receives the original from the carry-in entrance. The surface on which the exposure apparatus is laid is a floor surface,
2. The transport system according to claim 1, wherein the travel path has a height such that a lower part to the floor surface is a space in which an operator with respect to the exposure apparatus can walk. The surface on which the exposure apparatus is laid is under the floor,
The transport system according to claim 1, wherein a height at which the travel path is installed is the same as a floor surface.   4. A height of a position where the original is received from the carry-in port inside the exposure apparatus is the same as a height of an original stage holding the original during the exposure process. The transfer system according to any one of the above.   The exposure apparatus includes a transport mechanism that can transport the original plate from the carry-in entrance to the original stage by moving in a horizontal direction, and a storage unit that stores the original plate installed at a position that matches the transport path of the transport mechanism. 5. The transport system according to claim 4, further comprising: A step of exposing the substrate using the exposure apparatus employed in the transport system according to claim 1;
Developing the substrate exposed in the step;
A device manufacturing method comprising:

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