JP3211342B2 - Automatic gas filling station for unmanned carrier with inert gas cylinder for clean room - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic guided vehicle for use in a clean room, and more particularly to an automatic gas filling station for an automatic guided vehicle equipped with an inert gas cylinder.

[0002]

2. Description of the Related Art Semiconductor ICs and the like are always manufactured in a clean room where air is cleaned. However, as the degree of integration of a semiconductor integrated circuit increases, natural ICs formed on the surface of a semiconductor wafer or a substrate for an electronic material are formed. Oxide film becomes a problem,
In order to improve the yield, it is necessary to suppress the growth of the natural oxide film.

In the above-mentioned clean room, an unmanned transport vehicle equipped with a transfer robot is used to transport a semiconductor wafer from one process to the next process, and the time required for transport between the processes is usually several minutes. Since it takes about one hour or more to form the problematic natural oxide film, the natural oxide film is not exposed to the atmosphere during this transport period. In this state, the inter-process transfer was performed.

Although the formation of the natural oxide film does not need to be considered as a problem in the state where the transfer system using the automatic guided vehicle is operating normally, the failure and transfer of the semiconductor manufacturing apparatus which is the transfer destination are not considered. If the automated guided vehicle does not operate as scheduled due to a system failure, a stoppage of equipment or equipment due to a power outage, or a failure in the transport path, the state in which the semiconductor wafer is left on the automated guided vehicle will continue for a long time. During this time, there is a problem that the above-mentioned natural oxide film grows rapidly.

[0005] Therefore, the inventors of the present invention have proposed that even if a semiconductor wafer or the like is mounted and its transportation is interrupted for a long time due to its own cause or a cause such as a transfer / transportation destination, the present inventor has a problem. An unmanned transfer device capable of suppressing the formation of the natural oxide film has been proposed.

This unmanned transport device will be described with reference to FIGS. 3 and 4.

3 and 4, reference numeral 1 denotes a wafer cassette accommodating a semiconductor wafer 2, and reference numerals 10 and 20 denote semiconductor manufacturing apparatuses. The semiconductor manufacturing apparatuses 10 and 20 are arranged in a clean room at a certain interval. Reference numeral 30 denotes an automatic guided vehicle, on which a transfer robot 31 is mounted near one end on a top plate 30B of a bogie frame 30A, and a transfer box 40 is mounted and fixed on another portion on the top plate 30B. . 32
Is a drive wheel, and 33 is a caster.

The transport box 40 has a lid 42 attached to the box body 41 by a hinge (not shown).
The presence sensor 43 is provided inside. The lid 42 is opened and closed by an opening / closing mechanism (not shown), for example, an electric cylinder. A gas inlet 44 and an exhaust port 45 are provided on the bottom wall of the transfer box 40.
Are formed.

In the bogie frame 30A of the automatic guided vehicle 30, an inert gas cylinder (in this example, a nitrogen gas cylinder) is provided.
50 is provided, and the opening of the nitrogen gas cylinder 50 and the gas inlet 44 of the transport box 40 are connected by a pipe 52 in which a pressure reducing valve 51 and a gas supply valve 53 are interposed. An exhaust pipe 55 having an exhaust valve 54 extends from the exhaust port 45 of the transport box 40 into the bogie frame 30A through the top plate 30B. Reference numeral 60 denotes a controller which inputs detection signals of sensors, which will be described later, and transmits and receives required timing signals to and from a main controller (not shown) which controls the automatic guided vehicle 30 and the transfer robot 31. Then, in addition to outputting an opening / closing signal for the gas supply valve 53 and the exhaust valve 54, a signal for opening / closing the lid 42 of the transport box 40 is output.

[0010]

Now, assume that the wafer cassette 1 on the semiconductor manufacturing apparatus 20 is transported to the semiconductor manufacturing apparatus 10. When the automatic guided vehicle 30 stops at a predetermined position in front of the semiconductor manufacturing apparatus 20 or reaches a position before the predetermined position, (1) synchronization with the timing signal output from the main control device to the controller 60 Then, the electric cylinder of the transport box 40 extends to open the lid 42. When the lid 42 is opened to a predetermined position, a lid open detection sensor (limit switch) (not shown) operates. When the vehicle stops at a predetermined position in front of the semiconductor manufacturing apparatus 20, the arm and the arm of the transfer robot 31 are provided on condition that the lid open detection limit switch generates a detection signal.
The wrist starts a transfer operation according to a predetermined program.

(2) When the wafer cassette 1 is stored in the transfer box 40 from the semiconductor manufacturing apparatus 20 by the transfer operation of the transfer robot 31, the presence sensor 43 outputs and the electric motor of the transfer box 40 is electrically driven. The lid 41 is closed by the contraction operation of the cylinder. When the lid 42 is closed, a lid closing detection sensor (limit switch) (not shown) operates.

(3) When the lid 42 is completely closed, that is, when the above-mentioned lid closing detection limit switch outputs, the controller 6
At 0, a timer (not shown) starts counting, the exhaust valve 54 opens, the gas supply valve 53 opens, and nitrogen gas is spouted from the nitrogen gas cylinder 50 into the transfer box 40. The air in the transfer box 40 is pushed out by the nitrogen gas and exhausted from the exhaust port 45 into the bogie frame 30A, and the inside of the transfer box 40 is replaced with the nitrogen gas. The time Tk required for the gas replacement is set by the timer. When the timer expires, the exhaust valve 54 closes, and then the gas supply valve 53 closes.

(4) When the exhaust valve 54 and the gas supply valve 53 are closed, the automatic guided vehicle 30 executes a traveling program toward the semiconductor manufacturing apparatus 10 and starts traveling toward the semiconductor manufacturing apparatus 10.

(5) The automated guided vehicle 30 is the semiconductor manufacturing apparatus 1
When the vehicle stops at a predetermined position before 0 or reaches a position before the predetermined position, the electric cylinder of the transport box 40 is synchronized with a timing signal output from the main control device to the controller 60. When the cover 42 is opened by the extension operation and the automatic guided vehicle 30 stops at a predetermined position in front of the semiconductor manufacturing apparatus 10, the arm / wrist of the transfer robot 31 starts the transfer operation according to a predetermined program, and the transfer box 31 The wafer cassette 1 in the semiconductor manufacturing apparatus 10
Will be transferred to

In this unmanned transfer device, the semiconductor wafer 2
Is transported from a predetermined position to a predetermined position in a state where the atmosphere in the transfer box 40 is a nitrogen gas atmosphere which is an inert gas. For this reason, even if the automatic guided vehicle 30 is forced to stop for a long time (sufficient time for the natural oxide film to grow) during the transfer, the growth of the natural oxide film on the surface of the semiconductor wafer 2 may occur. Can be suppressed.

[0017]

However, if the gas in the inert gas cylinder 50 has been consumed,
Each time, the inert gas cylinder 50 must be replaced with a new inert gas cylinder, and replacing the inert gas cylinder manually requires labor and may cause contamination in the clean room.

The present invention has been made in order to solve this problem, and an object of the present invention is to provide an automatic gas filling station for an unmanned transfer device equipped with an inert gas cylinder for a clean room, which does not require replacement of the inert gas cylinder. And

[0019]

In order to achieve the above object, the present invention provides a movable coupler unit having a gas supply coupler, and a gas receiver for an automatic guided vehicle in which the movable coupler unit is stopped at a station. An advancing / retracting drive mechanism for advancing / retreating the fixed coupler unit having, a gas supply pipe for filling having a valve connecting the gas supply coupler to an inert gas main tank, and a communication device with the vehicle-side communication device of the automatic guided vehicle A ground-side communication device, a coupler coupling detection circuit including a detection terminal provided on the movable coupler unit so as to be able to make electrical contact with a detection terminal provided on the fixed coupler unit, and a gas filling control device, The automatic guided vehicle transports a conveyed product in a container, and the container is mounted via a gas supply path so that the internal atmosphere can be replaced. A transport vehicle connected to the gas cylinder, the stationary coupler unit has a configuration which is contacted to the inert gas cylinder through the fill for supply gas pipe provided with a valve.

According to the second aspect, the movable coupler unit and the fixed coupler unit have an exhaust gas coupler, the exhaust gas coupler of the movable coupler unit is connected to the exhaust gas pipe, and the exhaust gas coupler of the receiving gas coupler unit is disconnected through the exhaust gas pipe equipped with a valve. Contacted the activated gas cylinder,
Both valves, together with the valve of the gas supply pipe for filling, were configured to be opened and closed prior to the start of gas filling into the inert gas cylinder.

According to a third aspect of the present invention, the gas filling control device is configured to control the forward / backward drive mechanism, check the coupler connection, determine whether or not to start filling, and control the opening and closing of the valve.

According to a fourth aspect of the present invention, the determination as to whether or not to start charging is made based on a measurement signal of an oxygen concentration meter provided in the exhaust gas pipe.

[0023]

According to the present invention, when the automatic guided vehicle stops at the station, the station side communicates with the automatic guided vehicle side while connecting the gas supply coupler / gas receiving coupler and opening the valve in the gas supply pipe to the main tank. Automatically proceed with the formation of the gas supply path between the car and the gas cylinder on the vehicle side.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 100 denotes a ground gas supply station provided at a predetermined position in a clean room. The station box 101 of the ground gas supply station 100 has a movable coupler unit 102 at a front surface thereof at a predetermined height from the floor surface FL, and an advance / retreat drive mechanism for driving the movable coupler unit 102 forward / backward in the front / rear horizontal direction. 120 built-in. The movable coupler unit 102 has upper and lower gas supply couplers 103P of a tube and exhaust gas couplers 104P of a tube, and a detection terminal 105P for confirming coupler coupling is provided between the two.
From inside the station box 101, a filling gas supply pipe 106 connected to a large-capacity inert gas main tank 200 placed outside the clean room extends outside and an exhaust gas pipe 107 extends outside the clean room. The gas supply pipe 106 is connected to the gas supply coupler 103P by a flexible connection pipe 108, and the exhaust gas pipe 107 is connected to the exhaust gas coupler 103P by a flexible connection pipe 109. On-off valve 1 with adjustable flow rate in gas supply pipe 106
The exhaust gas pipe 107 is provided with an oxygen concentration meter 112 and an opening / closing valve 113. 1
Reference numeral 14 denotes a gas filling control device. Gas filling control device 11
4 will be described later.

A fixed coupler unit 70 is mounted on one of the left and right side plates of the automatic guided vehicle 30. The fixed coupler unit 70 has a tube gas receiving coupler 103N and a tube exhaust gas coupler 104N above and below, and a coupler connection detection terminal 105N is provided between the two. An opening / closing valve 71 is connected to the mouth of the inert gas cylinder 50, and a gas receiving coupler 103 </ b> N is connected to the valve 71 via a filling gas supply pipe 73 having an opening / closing valve 72.
The exhaust gas coupler 104N is connected to the on-off valve 71 via an exhaust gas pipe 75 having an on-off valve 74. 76 is the pipe 52
This is the open / close valve inside. 77 is a thermometer for measuring the temperature of the inert gas cylinder 50, 78 is a pressure gauge for measuring the pressure of the inert gas cylinder 50, and the measurement signal is sent to the gas filling control device 80 on the vehicle control side. 90 is a vehicle control device.

Reference numeral 115P denotes an optical communication device provided in the station box 101.
An optical communication device 115N capable of communicating with the vehicle is provided on one of the left and right side plates of the automatic guided vehicle 30.

Detection terminals 105P and 1 for coupler coupling confirmation
05N, as shown in FIG. 2, constitutes a coupler coupling detection circuit together with the relay 117. When the coupling coupling detection terminals 105P and 105N come into electrical contact with each other,
The relay circuit is closed and the relay 117 is energized, and the output of the contact 117a is supplied to the gas charging control device 114 as a coupler coupling detection signal. Reference numeral 118 denotes a battery.

In a state where the coupler coupling detection signal is generated, as shown in FIG.
The end and the end of the gas receiving coupler 103N are airtightly engaged in a press-contact manner, and the end of the exhaust gas coupler 104P and the end of the exhaust gas coupler 104N are airtightly engaged in a press-contact manner.

(1) In this configuration, the automatic guided vehicle 30
Self-propelled to the ground gas station 100 and stops at a predetermined position of the ground gas station 100, the vehicle control device 90 of the automatic guided vehicle 30 sends a signal indicating that the vehicle has stopped at the predetermined position from the optical communication device 115N. . The transmitted signal is received by the optical communication device 115P and reported to the gas filling control device 114.

(2) Upon receiving this report, the gas filling control unit 114 gives the forward / backward drive mechanism 103 a forward command. As a result, the forward / backward drive mechanism 120 is connected to the movable coupler unit 10.
2 is moved to the automatic guided vehicle 30 side.

(3) Upon receiving this report, the gas filling control unit 114 causes the advance / retreat drive mechanism 120 to move the forward finger movable coupler unit 102 toward the unmanned carrier 30 by a predetermined distance, and to receive the end of the gas supply coupler 103P. Gas coupler 1
03N is pressed against the flared receiving end of the exhaust gas coupler 104P and the flared end of the exhaust gas coupler 104P is
The end portions are pressed into contact with each other, and the above-described coupler coupling detection circuit is closed, and a coupler coupling detection signal is generated. The gas filling control device 114 transmits the coupler coupling detection signal to the vehicle control device 1 through the optical communication device 115P and the optical communication device 115N.
16 to be transmitted.

(4) When this transmission is completed, the gas filling control device 114 on the station side issues a valve opening command to the on-off valves 110 and 113, and the gas filling control device 80 on the automatic guided vehicle 30 sends the on-off valve 71 , 76 and a valve opening command to the on-off valves 72, 74. Thereby, the main tank 200 → the gas supply pipe 106 for filling to the coupler 103P →
Coupler 103N → gas supply pipe 73 for filling → exhaust gas pipe 7
5 → coupler 104P → coupler 104N → exhaust gas pipe 107 → high-pressure N ₂ gas flows on a path outside the clean room, and air remaining on the path is discharged outside the clean room.

(5) When the oxygen concentration meter 112 provided in the exhaust gas pipe 107 detects an oxygen concentration equal to or less than a predetermined value, the gas filling control device 114 notifies the vehicle control device through the optical communication device 115P and the optical communication device 115N. 90, and at the same time, gives a valve closing command to the on-off valve 113. On the automatic guided vehicle 30 side, the vehicle control device 90 gives a gas filling start command to the gas filling control device 80, and the gas filling control device 80 gives a valve opening command to the on-off valve 71 and a valve closing command to the on-off valve 74. . Thereby, the N ₂ gas is supplied from the main tank 200 to the inert gas cylinder 50.

(6) On the automatic guided vehicle side, the gas filling control device 80 takes in the measured outputs of the thermometer 77 and the pressure gauge 78 and monitors the internal state of the inert gas cylinder 50.
When the filling of the inert gas cylinder 50 is completed, the vehicle control device 90 notifies the optical communication device 115N and the optical communication device 11
Notifying the gas filling control device 114 through 5P, the gas filling control device 80 gives a valve closing command to the on-off valve 72,
After giving a valve closing command to the on-off valve 110, the gas filling control device 114 commands the retraction drive mechanism 120 to perform retreat driving.

In this embodiment, before starting gas filling into the inert gas cylinder 50, N _{2 is transferred} from the main tank 200 to the above-described gas supply pipe 106 to the exhaust gas pipe 107 to the path outside the clean room. Since the gas flows, the inert gas cylinder 50 can be filled with pure N ₂ gas.

[0037]

As described above, according to the present invention, when the automatic guided vehicle stops at the station, the station side communicates with the automatic guided vehicle side while connecting the gas supply coupler / gas receiving coupler and the gas supply pipe. Since the formation of the gas supply path between the main tank and the vehicle-side gas cylinder by opening the valve is automatically advanced, the labor for replacing the vehicle-side gas cylinder can be omitted.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is an enlarged view of a main part in the embodiment.

FIG. 3 is a diagram showing one example of a conventional inside of a clean room.

FIG. 4 is a diagram showing an example of the automatic guided vehicle in the above-described conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Wafer cassette 2 Semiconductor wafer 10, 20 Semiconductor manufacturing apparatus 30 Unmanned transport vehicle 30A Truck frame 30B Top plate 31 Transfer robot 50 Nitrogen gas cylinder 70 Fixed coupler unit 71, 72, 74, 76 On-off valve 73, 106 Filling gas supply pipe 75, 107 Exhaust gas piping 77 Thermometer 78 Pressure gauge 80 Gas filling control device 90 Car control device 100 Automatic filling station 101 Station box 102 Movable coupler unit 103P, 104P Movable coupler unit coupler 103N, 104N Fixed coupler unit coupler 105P, 105N Detection terminal 110, 113 Open / close valve 112 Oxygen concentration meter 114 Gas filling control device 115P, 116N Optical communication device 120 Advance / retreat drive mechanism 200 Main tank

──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Kono, etc.100 Takegahana-cho, Ise-shi, Mie Prefecture Inside Shinsei Electric Machinery Co., Ltd. (72) Inventor Atsushi Okuno 100-ketakehana-cho, Ise-shi, Mie Prefecture Inside Ise Works (72) Inventor Masanori Tsuda 100 Takegahana-cho, Ise City, Mie Prefecture Shinko Electric Machinery Co., Ltd. Toshihide Abe (56) References JP-A-63-19995 (JP, A) JP-A-64-23308 (JP, A) JP-A-2-127192 (JP, A) JP-A-2-243417 (JP) JP-A-3-15000 (JP, A) JP-A-3-113516 (JP, A) JP-A-5-310323 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB Name) F17C 5/00-5 / 06 F17C 13/00-13/08

Claims (4)

(57) [Claims] A movable coupler unit having a gas supply coupler; an advance / retreat drive mechanism for moving the movable coupler unit forward / backward with respect to a fixed coupler unit having a gas receiver coupler of an automatic guided vehicle stopped at a station; and the gas supply coupler. Filling gas supply pipe with a valve that communicates with the inert gas main tank, a ground-side communication device capable of communicating with the vehicle-side communication device of the automatic guided vehicle, and a detection terminal provided on the fixed coupler unit A coupler coupling detection circuit including a detection terminal provided in the movable coupler unit so as to be capable of making electrical contact, and a gas filling control device, wherein the automatic guided vehicle transports a conveyed product by storing it in a container, and Is a carrier connected to an inert gas cylinder mounted via a gas supply path so that the internal atmosphere can be replaced, wherein the gas receiving coupler unit is An automatic gas filling station for an unmanned transfer device equipped with an inert gas cylinder for a clean room, wherein the unit is connected to the inert gas cylinder through a gas supply pipe having a valve. 2. The movable coupler unit and the fixed coupler unit have an exhaust gas coupler, the exhaust coupler of the movable coupler unit is connected to an exhaust gas pipe, and the exhaust coupler of the fixed coupler unit is connected to an inert gas cylinder through an exhaust gas pipe having a valve. 2. The unmanned transfer device with an inert gas cylinder for a clean room according to claim 1, wherein both valves are opened and closed together with a valve of a gas supply pipe for filling before the start of gas filling into the inert gas cylinder. Automatic gas filling station. 3. The inert gas cylinder for a clean room according to claim 1, wherein the gas filling control device controls an advance / retreat driving mechanism, confirms coupler coupling, determines whether or not to start filling, and controls opening and closing of a valve. Automatic gas filling station for unmanned carrier. 4. The gas for an unmanned transfer device equipped with an inert gas cylinder for a clean room according to claim 3, wherein the determination as to whether or not to start filling is made based on a measurement signal of an oxygen concentration meter provided in the exhaust gas pipe. Automatic filling station.