JP2002110766A - Transfer system and method of transfer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transfer system capable of shortening transfer time, when express transfer is required. SOLUTION: For transferring a carrier 1 from a stocker A to a stocker B a transfer command controller HOST first sends an outgoing stock controller STC-A connected to the stocker A a command to move the carrier 1 to an outgoing window 2 of the stocker A. Then, the outgoing stock controller STC-A receiving a command from the transfer command controller HOST for lifting the carrier 1 located on a shelf of the stocker A down the outgoing window 2. At the same time as the receipt of this instruction, the outgoing stock controller STC-A sends a request for sending a vehicle 5 to a transfer controller LVC.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transfer system for transferring a lot of semiconductor wafers between processing steps of a production line for semiconductor devices and the like.

2. Description of the Related Art In a manufacturing factory for semiconductor devices and the like, processing steps such as cleaning, drying, and etching of semiconductor wafers are performed by separately separated processing units for each lot. The processing equipment that performs each processing for this lot includes a lot to be transported to the processing equipment in the subsequent process and a transport shelf (stocker) for temporarily storing the lot transported from the previous process. It is attached as. And each stocker has its own shelf,
It has a loading / unloading port and a crane for transportation, and the lot can be moved between the shelf and the loading / unloading port by controlling the crane.

Further, each stocker is linked by a track, and an unmanned transport vehicle (vehicle) loaded with the lot moves on the track to move a lot of semiconductor wafers to a predetermined processing apparatus which is the next processing step. Transport to Such a lot transfer system is usually automated, and the operation efficiency of the production line is improved. In general, a semiconductor wafer lot transfer system includes a transfer command controller that supervises the entire transfer system, and a controller for each unit connected to the controller via a network. These include a delivery controller that manages the loading and unloading of lots on vehicles in each stocker, and a transport controller that controls the operation of vehicles that load and transport lots on tracks connected between stockers. There is a controller. Then, the transfer command controller instructs each controller to issue a lot transfer command.

In such a transport system, the vehicle is loaded with a carrier containing one lot of semiconductor wafers and travels on a track, so that the stocker of the transporter comes out of the outlet of the transporter stocker. The carrier is transported to the entrance of the warehouse. Normally, an unoccupied vehicle waits for a transfer command from a transfer command controller while traveling or waiting on an orbit with the unloaded vehicle.

In such a semiconductor wafer transfer system, an express transfer may be performed during a normal lot transfer. The express transport is, for example, a process in which one lot of semiconductor wafers whose parameters and the like are changed for testing for the purpose of improvement are newly stored in a carrier and transported with priority over other normal lots.

Hereinafter, the operation of the transport system according to the prior art will be described. FIG. 3 is a diagram showing a message sequence between controllers in a conventional transport system. In FIG. 3, the stocker A is a lot transfer source, and the stocker B is a lot transfer destination. HOST is a transfer command controller, STC-A and STC-B are a delivery controller and a storage controller, respectively, and LVC is a transfer controller. First, the transfer command controller HOST is connected to the retrieval controller ST.
Instruct CA to move the carrier storing the lot from the shelf of the stocker A to the outlet using the crane (S31). Then, the transport command controller HOST confirms that the carrier has been moved to the outlet of the stocker A.

Next, the transport command controller HOST causes the transport controller LVC to move the vehicle that transports the carrier to the outlet of the stocker A. When the vehicle arrives at the exit of the stocker A, the transport command controller HOST instructs the exit controller STC-A to load the carrier moved to the exit into the vehicle (S32). Then, the transport command controller HOST instructs the transport controller LVC to move the vehicle loaded with the carrier to the entrance of the stocker B. When the vehicle arrives at the storage opening of the stocker B, the transport command controller HOST instructs the storage controller STC-B to unload the carrier from the vehicle. Then, the transport command controller HO
The ST confirms that the carrier has been unloaded.

[0008] Further, a controller HOST for a transfer command.
Instructs the storage controller STC-B to move the carrier from the storage opening of the stocker B to the shelf (S
33). Then, the transfer command controller HOST confirms that the carrier has entered the shelf. The above is an operation example of the conventional transport system.

[0009]

However, in the conventional transport system, all the instructions relating to the transport are issued from the transport command controller.
It took tens of seconds to bring the vehicle into the stocker where it was transported. Therefore, once the transfer command is issued from the transfer command controller to the transfer controller, the next command is performed until the transfer command controller confirms that the vehicle arrives at the exit of the stocker of the transfer source. Was unable to do so and was treated as a wait.

The present invention has been made in view of such circumstances, and reduces the waiting time by allocating a vehicle to a stocker of a transporter earlier, thereby reducing the time required for transport when an express transport is required. It is an object to provide a transport system that can be shortened.

[0011]

According to a first aspect of the present invention, an unmanned transport vehicle travels along a track and transports a load loaded on the transport vehicle. In a transport system configured to transport articles between storage locations, a transport command controller that issues a transport command for the transported article, and a dispatch request is issued on condition that the transport command is received, and A delivery controller that controls the delivery of the conveyed goods from the original storage location to loading on the carrier on the track, and controls the operation of the carrier on the track, and issues a command from the controller for delivery. And a transfer controller for receiving the request for the dispatched vehicle and directing the transporting vehicle traveling or waiting on the track to the storage location of the transport source.

According to a second aspect of the present invention, in the first aspect of the present invention, the storage location has a crane for moving the conveyed goods, a shelf for storing the goods, and a discharge port for discharging the goods. A controller controls the crane to move the conveyed article from the shelf to the outlet.

According to a third aspect of the present invention, in the first aspect of the present invention, when the delivery controller receives the transport command, the delivery controller gives priority to a process for issuing the dispatch request. It is characterized by the following.

According to a fourth aspect of the present invention, in the first aspect of the invention, the transported object is a semiconductor wafer.

According to a fifth aspect of the present invention, in the first aspect of the invention, the conveyed object is a liquid crystal substrate.

According to a sixth aspect of the present invention, there is provided a transportation apparatus configured to run an unmanned transport vehicle along a track and transport the transported goods loaded on the transport vehicle between storage locations of the transported goods. In the method, a first step in which a transfer command controller issues a transfer command of the transfer article, and a delivery controller issues the transfer article from a storage location of a transfer source on condition that the transfer command is received. A second step of performing control, and a third step in which the exit controller issues a vehicle allocation request on condition that control of exiting the conveyed article is performed;
A fourth step in which the transport controller directs the transport vehicle traveling or waiting on the track to the storage location of the transport source, on condition that the request for dispatch is received; and The method may further include a fifth step of controlling the loading of the transported object on the transport vehicle, and a sixth step of controlling the operation of the transport vehicle on the track by the transport controller.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a configuration of a transport system for a semiconductor wafer lot or the like according to an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a carrier, which is an apparatus for accommodating, for example, a lot of semiconductor wafers manufactured in a manufacturing factory in which the transfer system is installed. In this transport system, when a lot is transported from one processing step to the next processing step, the lot is stored in the carrier 1 and transported.

A is a transport shelf (stocker), and in this embodiment, unloads a carrier 1 containing a lot. The stocker A is a part of a processing apparatus that performs a certain processing step, and has a shelf, a delivery port of the carrier 1, and a crane. 2
Is an outlet of the carrier 1 in the stocker A, and the carrier 1 is carried out of the shelf through the outlet 2.
B is also a stocker, and in this embodiment, is a side where the transported carrier 1 is stored. The stocker B is also a part of a processing apparatus that performs a certain processing step, and has a shelf, a storage port, and a crane. Reference numeral 3 denotes a storage port of the stocker B, and the carrier 1 is stored in a shelf inside the stocker B through the storage port 2. That is, in the process of processing a semiconductor wafer or the like, the stocker A is a pre-process and the stocker B is a post-process stocker.

Reference numeral 4 denotes a trajectory of the transport system which is in contact with the outlet 1 of the stocker A and the inlet 2 of the stocker B and is also connected to other stockers. Reference numeral 5 denotes a transport vehicle (vehicle) on which the carrier 1 is loaded and circulates on the track 4. The vehicle 5 loads the carrier 1 from the outlet 2 of the stocker A as the transport source and transports the carrier 1 to the inlet 3 of the stocker B as the transport destination.

The STC-A is a storage controller for the stocker A, and controls the carrier 1 temporarily stored on a shelf in the stocker A to the storage port 2 using a crane. STC-B is a storage controller for the stocker B, and controls to temporarily store the carrier 1 conveyed from the storage port 3 of the stocker B on a shelf using a crane. LVC is a transport controller, which transports the carrier 1 between the stockers A and B by controlling the vehicle 5.
The HOST is a host controller that instructs a delivery command to the delivery controller STC-A, the storage controller STC-B, and the transport controller LVC. 6 is a transfer command controller HOST, stocker A
Is a network that connects the storage controller STC-A, the storage controller STC-B, and the transport controller LVC, related to the stocker B, to each other,
Communication between the controllers is possible.

Next, an operation example of the transport system in the present embodiment will be described with reference to FIG. FIG. 2 is a diagram showing a message sequence between controllers in the transport system shown in FIG. FIG. 2 shows a sequence of the transport system of the present invention in a case where the carrier 1 storing a lot of semiconductor wafers temporarily stored on the shelf of the stocker A is temporarily stored on the shelf of the stocker B. I have.

First, the transport command controller HOST instructs the delivery controller STC-A of the stocker A to move the carrier 1 temporarily stored on the shelf of the stocker A to the delivery port 2 by a crane. (S21). When receiving the instruction from the transfer command controller HOST, the retrieval controller STC-A moves the carrier 1 to the retrieval port 2 using a crane. At the same time, the transfer controller LVC is instructed to move one of the empty vehicles 5 traveling or waiting on the transfer track 4 to the exit 2 (S22). Then, the transport command controller HOST
Confirms that the carrier 1 has been moved to the outlet 2 of the stocker A.

Here, the delivery controller STC-A relating to the stocker A and the transport controller LVC can communicate with each other using the network 6. Therefore, during the express transport of the carrier 1, the vehicle 5 is synchronized with the start of the crane operation of the stocker A as the transport source.
Prior to the instruction of the transfer command controller HOST, is called into the exit 2 to temporarily wait. However, this is not based on the transfer command of the carrier 1 but for temporarily stopping the vehicle 5 circulating or waiting on the track 4 in front of the exit of the stocker performing the express transfer. That is, the transfer command is performed by the transfer command controller HOST.

Next, the transfer command controller HOST instructs the transfer controller LVC to dispatch the vehicle 5 to load the carrier 1 on the vehicle 5 (S23). At this time, since the vehicle 5 has already been instructed to move to the exit 2 by the exit controller STC-A for the stocker A, the vehicle 5 is dispatched immediately or in a shorter time than before. For example, it took several tens of seconds to dispatch a vehicle immediately,
It is possible to dispatch vehicles to the exit within seconds.

Then, a controller HOST for a transfer command is provided.
Gives an instruction to load the carrier 1 in the exit 2 to the vehicle 5 to the exit controller STC-A relating to the stocker A. After the carriers 1 are loaded on the vehicle 5, the transport command controller HOST instructs the transport controller LVC to transport the vehicle 5 to the entrance 3 of the stocker B. When the vehicle 5 arrives at the entrance 3, the transport command controller HOST instructs the entry controller STC-B of the stocker B to unload the carrier 1 from the vehicle 5 (S2).
4). As a result, the carrier 1 is unloaded to the storage port 3 of the stocker B. Then, the transport command controller HO
The ST confirms that the carrier 1 has been unloaded.

In the stocker B, the carrier 1 is temporarily stored on the shelf from the entrance 3 using a crane in accordance with an instruction from the transfer command controller HOST to the storage controller STC-B for the stocker B. Then, the transport command controller HOST confirms that the carrier 1 has been stored. With the above process, the process of transporting a transported object such as a lot of semiconductor wafers from the stocker A to the stocker B is completed.

In the above-described embodiment, the transport system for transporting the carrier 1 temporarily stored in the stocker A to the stocker B has been described. However, each stocker may have both the entry and exit functions. It is. The transfer system of the present invention is applicable not only to semiconductor wafer lots but also to liquid crystal substrate production lines. Furthermore, in the transport system for semiconductor wafers, interface standardization (SEM) is being promoted worldwide.
By applying the present invention, it is not necessary to change this interface, and it is possible to perform more efficient express transport. In this embodiment, the express transport has been described. However, even in the transport that does not require the express, by applying the present embodiment, the efficient operation management of the vehicle can be performed.

[0028]

As described above, according to the present invention, there is provided a transport command controller for issuing a transport command for a transported article, a delivery controller for issuing a dispatch request on condition that the transport command is received, and A transport controller that directs the transport vehicle to the transport source storage location in response to a vehicle allocation request is provided, so that vehicles can be distributed to the transport source stocker sooner, reducing waiting time, and This has the advantage that the time required for transport can be reduced.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a transport system for a lot of semiconductor wafers and the like according to an embodiment of the present invention.

FIG. 2 is a diagram showing a message sequence between controllers in the transport system shown in FIG.

FIG. 3 is a diagram showing a message sequence between controllers in a conventional transport system.

[Explanation of symbols]

 A, B Transport shelf (stocker) 1 Carrier 2 Outgoing port 3 Entry port 4 Track 5 Transport vehicle (vehicle) 6 Network STC-A Outgoing controller STC-B Ingoing controller LVC Transport controller HOST Transport command controller

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3F022 AA08 CC02 EE05 FF01 JJ07 LL12 MM08 MM13 MM35 MM44 5F031 CA02 CA05 GA59 MA23 MA24 PA03 5H301 AA02 AA09 BB05 CC06 DD07 EE02 KK02 KK04 KK14 KK20

Claims (6)

[Claims] 1. An unmanned carrier is driven along a track,
In a transport system configured to transport a transported object loaded on the transport vehicle between storage locations of the transported item, a transport command controller that transmits a transport instruction of the transported item, and receiving the transport instruction. A dispatch controller that issues a dispatch request on the condition that the article is delivered from the storage location of the transport source and controls the loading of the article on the track on the track, and A transport controller for controlling the operation and receiving the request for dispatching issued from the delivery controller, and directing the transporting vehicle traveling on the track or on standby to the storage location of the transport source. A transport system comprising: 2. The storage location has a crane that moves the conveyed goods, a shelf that stores the goods, and an exit that exits, and the exit controller controls the crane,
The transport system according to claim 1, wherein control is performed to move the transported article from the shelf to the outlet. 3. The transport system according to claim 1, wherein, when the transport controller receives the transport instruction, the controller performs a process for issuing the vehicle allocation request with priority. 4. The transport system according to claim 1, wherein the transported object is a semiconductor wafer. 5. The transport system according to claim 1, wherein the transported object is a liquid crystal substrate. 6. An unmanned carrier traveling along a track,
In a transport method configured to transport a load loaded on the transport vehicle between storage locations of the load, a first step in which a transfer command controller issues a transfer command of the load, On the condition that a transfer command is received, a second step in which the delivery controller performs control to discharge the conveyed product from the storage location of the transfer source, and A third step in which the transportation controller issues a request for dispatching, and on the condition that the request for dispatching is received, the transportation controller places the transporting vehicle traveling or waiting on the track on the storage location of the transportation source. And a fifth step in which the outgoing controller controls loading of the article on the transport vehicle, and the transport controller controls operation of the transport vehicle on the track. Conveying method characterized by having a sixth step.