JP3084825B2 - Mechanical interface device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mechanical interface device used in a semiconductor manufacturing process.

[0002]

2. Description of the Related Art Conventionally, semiconductor processing has been carried out in a specially designed clean room in order to prevent particle contamination of the semiconductor. Since there is a limit in reducing the contamination level of particle contamination, for example,
A standardized mechanical interface device (SMIF device) has been developed as disclosed in Japanese Patent Application No. 0-143623.

As shown in FIG. 5, for example, this SMIF apparatus houses a wafer processing apparatus (not shown) and is filled with clean air and a main body case 1 of the apparatus, and a portable type box (hereinafter, referred to as a box). A pod POD) 10 and a transport device 30. Main unit case 1 of the main unit
The top plate 2 has a port 4 (a loading / unloading port for the wafer cassette 20) 4 formed by a port plate 3, and a pod POD 10 having a grip portion 10A is placed on the port plate 3. The pod POD 10 has a shape having an annular flange 12 around an opening 11 thereof.
The transport device 30 in this example is a lifting device, and the lifting shaft 32
The wafer cassette 20 is placed on a lift table 31 supported by the controller and lifted up and down. This lift table 31 is a port door. Of the main body case 1 to the outside, and the wafer cassette 2 on the port door 31.
The base 21 of the pod contacts the periphery of the opening 11 of the pod POD 10 to seal the opening 11. The table 21 is hereinafter referred to as a pod door. Reference numeral 13 denotes a sealing material, which is a pod PO
The seal between the opening of D10 and the pod door 21, the seal member 14 seals between the flange 12 of the pod POD10 and the port plate 3, and the seal member 15 seals between the port plate 3 and the port door 31. . A lock mechanism 40 has a lock lever 41 driven by a geared motor (not shown), and has a function of pushing down the flange 12 of the pod POD 10 onto the port plate 3. In this example, after the wafer W before processing is transferred from another place (not shown) onto the port door 31, the pod POD 10 is placed on the port plate 3 and fixed by the lock lever 41. After being fixed by the lock lever 41, the port door 31 is lowered to the transfer position. When the port door 31 is lowered to the transfer position, a transfer device (not shown) transfers the wafer cassette 20 on the port door 31 to the processing machine.

[0004]

Conventionally, particle contamination of the wafer W has been a problem. However, as the density of semiconductor integrated circuits has increased, the natural oxide film on the wafer surface has been reduced due to oxygen in the air. The influence begins to become a problem, and in order to prevent the growth of this natural oxide film, the movement of the wafer W,
It is necessary to perform transportation, processing, and the like in an inert gas (N ₂ gas) atmosphere, and at present, the concentration of O ₂ and H ₂ O is 10 p.
An N ₂ gas atmosphere of not more than pm is required.

When using the above SMIF device,
And N ₂ gas atmosphere of air in the main body case 1 is replaced with N ₂ gas, the interior of the pod POD10 is being kept in N ₂ gas atmosphere, the pod POD10 is set on the top plate 2 of the casing 1 Each time, the inside is replaced with N ₂ gas to make a higher purity N ₂ gas atmosphere. The injection of N ₂ gas to the pod POD10 a portable type, it is necessary to perform the N ₂ gas cylinder provided in the main body case 1 side, the pod POD10 pod door 21
It is not easy to inject the N ₂ gas from the main body case 1 side while keeping the airtight, and the structure becomes complicated.

SUMMARY OF THE INVENTION The present invention has been made to solve this problem. A mechanical interface device capable of easily performing gas replacement in a pod and capable of performing the gas replacement by adding a simple member is provided. The purpose is to provide.

[0007]

In order to achieve the above object, according to the present invention, in the first aspect, a cylindrical space in which a port door can be raised and lowered at a predetermined height is formed inside, and a lower surface of the port door is airtightly sealed. A movable port skirt having a lower engaging peripheral portion capable of engaging with the upper surface and an upper engaging peripheral portion capable of airtightly engaging the lower surface of the port plate; and a member disposed on the port door or a member which moves up and down together with the port door. A biasing device for biasing the port skirt toward the port plate, wherein the port door is airtightly engaged with the lower engagement peripheral portion.
Until the pod door moves up
Above the sealed space that communicates with the inside of the pod.
Partition between the port plate side and the port play
The exhaust port that opens on the inner peripheral surface of the
Using an air supply port both connected to a N ₂ gas source,
The configuration was such that N ₂ gas was injected into the pod .

According to a second aspect of the present invention, the urging device is a suspending device held by the port door, and a suspending line having a coil spring at one end and an engaging roller engaged with a non-coil spring portion of the suspending line. A coil spring side end of the suspension wire is locked by a locking pin provided on the port door, and the non-coil spring portion is engaged with the engagement roller and hangs down to a lower engagement portion of the port skirt. The coil spring is locked to the lower engaging portion, and the coil spring is preloaded. In the third aspect, the biasing device is configured to include a plurality of preload coil springs interposed between the base fixed to the support shaft of the port door and the lower engagement portion of the port skirt.

[0009] According to claim 4, after the pod is set to the port plate, a port door is lowered a predetermined height, after the sealed space formed, a predetermined time or the N ₂ gas from the air inlet open to the exhaust port Injection was performed until the oxygen concentration became equal to or less than a predetermined value, the exhaust port was closed, and then the port door was lowered to the workpiece transfer position.

[0010]

According to the present invention, when injecting gas into the pod, the outer peripheral portion of the lower surface of the port door is lowered to a position where the sealing material is pressed between the lower portion and the lower engaging portion of the port skirt. As the port door is lowered, the spring of the biasing device contracts, but the spring is preloaded so that sufficient biasing force acts on the port skirt, so that the port skirt remains pressed against the port plate. When the port door is lowered, the pod door is also lowered together with the port door, so the pod opening is opened. Since the inside of the pod is airtightly shielded from the outside and the pod opening 11 is opened, the gas supply port and the gas exhaust port communicate with the inside of the pod.

[0011]

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

In FIG. 1, reference numeral 33 denotes a short cylindrical port skirt, which forms an internal space A in which the port door 31 can move up and down, and has a lower engaging peripheral part (lower part) at its lower end. A plurality of guide holes 33a are formed in the lower flange 33A, and the upper surface thereof has a sealing material 3 surrounding the plurality of guide holes 33a.
The sealing material (for example, O-ring) 34 is opposed to the outer peripheral portion of the lower surface of the port door 31. An outwardly facing upper engaging peripheral portion (upper flange) 33B is formed at the upper end of the port skirt 33, and a sealing material (for example, an O-ring) 33b is attached to the surface thereof. 35 extends vertically downward from the lower surface of the port door 31,
It is a guide rod having a stopper 35a at the lower end, and penetrates a corresponding guide hole 33a. Reference numeral 36 denotes a guide roller provided in the internal space 31A of the port door 31, and 37 denotes a biasing device (suspension tool) including a suspension wire having a coil spring 37A partially preloaded. Is locked by a locking pin 38 provided in the internal space 31A, and the other portion is engaged with the guide roller 36 and then pulled out from a hole 39 formed immediately below the guide roller 36 of the port door 31. The port skirt 33 is locked to the inner peripheral end of the lower flange 33A. The port skirt 33 is lifted up by a plurality of hanging members 37, and is in pressure contact with the lower surface of the port plate 3 with a seal member 33b interposed therebetween.

Reference numeral 3A denotes a gas supply port which penetrates a lower side of the port plate 3 in a radial direction, and is connected to an N ₂ gas cylinder (not shown) through a pipe 3a. Reference numeral 3B denotes a gas exhaust port penetrating the lower side of the port plate 3 in the radial direction, and 3C denotes an electromagnetic valve provided in the pipe 3b.

The inside of the box body case 1 is in an N ₂ gas atmosphere and is always pressurized by injecting 20 L / min of N ₂ gas.

Next, the operation of this embodiment will be described with reference to FIGS.

Now, it is assumed that the pod POD 10 is mounted on the port plate 3 of the main body case 1 from outside the apparatus, and is fixed on the port plate 3 by the lock lever 41 (not shown). In this state, the gap between the opening 11 of the pod POD10 and the pod door 21 is sealed with a sealing material 13, and the gap between the flange 12 of the pod POD10 and the port plate 3 is sealed with a sealing material 14. The space between the upper end of the port skirt 33 and the port plate 3 is sealed with a sealing material 33b.

Next, N ₂ gas is injected into the pod POD 10 to replace the inside with N ₂ gas. Before the gas injection, the port door 31 is moved by a predetermined small distance as shown in FIG. The outer periphery of the lower surface of the port door 31 is lowered to a position where the sealing material 34 is pressed between the lower surface 33A and the lower flange 33A. As the port door 31 is lowered, the coil spring 37A contracts. However, even in the state shown in the drawing, the coil spring 3A applies a tensile force to the other portion, and a sufficient lifting force acts on the port skirt 33.
Since port 7A is preloaded, port skirt 33 remains pressed against port plate 3. This port door 3
As the pod door 21 descends together with the port door 31 due to the lowering of the opening 1, the opening 11 of the pod POD 10 is opened. , And there is no possibility that the air in the pod POD 10 enters the main body case 1. When the port door 31 and the pod door 21 are lowered, the pod P
Since the opening 11 of the OD 10 is opened, the gas supply port 3A and the gas exhaust port 3B communicate with the inside of the pod POD10.

In this embodiment, as described above, after lowering the port door 31 to open the opening 11 of the pod POD 10, the solenoid valve 3C is opened, and N ₂ gas is supplied from the gas supply port 3A into the pod POD 10. To, for example, 70 liters / minute,
It was injected approximately 5 minutes, the air in the pod POD10 by exhaust from the gas outlet 3B substituting the pod POD10 with N ₂ gas.

When the gas replacement is completed, the port door 31 is lowered to a predetermined position (transfer position) as shown in FIG. Thus, pod POD10 is made to be in communication with the inside of the body casing 1, pod POD10 is _{N 2}
Than has become gas atmosphere, may be deteriorated N ₂ gas concentration of the body case 1 is not. When the port door 31 is lowered to the transfer position, the wafer cassette 20 on the port door 31 is transferred to the processing machine in the N ₂ gas atmosphere by a transfer device (not shown).

The wafer cassette 20 processed by the processing machine is transferred to the port door 31 by the transfer device (not shown).
The pod POD is transferred by the port door 31
After being carried inside, the port door 31 is moved up to the highest position to close the port 4 and then carried out of the apparatus.

In this embodiment, when the pod POD 10 is set on the port plate 3 after the wafer cassette 20 containing the wafer before processing is transferred onto the port door 31 closing the port 4. Then, the port door 31 is lowered by a predetermined small distance to form a sealed space A. After the sealed space A is formed, the inside of the pod POD10 is N.
_{After the} gas is replaced by the _two gases and the inside of the pod POD 10 becomes an N ₂ gas atmosphere, the inside of the pod POD 10 communicates with the inside of the main body case 1.

In the above description, N is inserted into the pod POD10.
_{2 The} gas injection is exemplarily described as 70 liters / minute, approximately 5 minutes. However, when an oxygen concentration meter is provided in the exhaust system including the gas exhaust port 3B, when the measured oxygen concentration falls below a predetermined value,
In some cases, the N ₂ gas injection is stopped.

In the above embodiment, the case where the main body case 1 accommodates the wafer processing apparatus and the like has been described. However, the main body case 1 may be a stocker in which the atmosphere is an N ₂ gas atmosphere.

FIG. 4 shows a second embodiment of the present invention. This embodiment is different in that a lifting coil spring 37D is used instead of the hanging member 37. A platform 37I serving as a spring seat is fixed to the elevating shaft 32 of the port door 31, and a plurality of coil springs 37D are arranged in a preloaded state between the platform 37I and the lower flange 33A of the port skirt 33. It is.

[0025]

As described above, according to the present invention, the port door is lowered to a predetermined height to form a sealed space communicating with the pod on the outer peripheral side of the port door and the pod door.
Since the N ₂ gas is injected into the pod from the external N ₂ gas source through the space, it is only necessary to provide a member that partitions the sealed space in cooperation with the port door and the pod door.
It requires, at low cost, it is possible to construct a highly reliable pod gas replacement system.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view showing a state when N ₂ gas is injected in the embodiment.

FIG. 3 is a vertical cross-sectional view showing a state during an object loading / unloading process in the embodiment.

FIG. 4 is a longitudinal sectional view showing a second embodiment of the present invention.

FIG. 5 is a diagram schematically showing a conventional SMIF device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main body case 3 Port plate 3A Air supply port 3B Exhaust port 3C Solenoid valve 4 Port 10 Pod POD 11 Pod POD opening 12 Pod POD flange 13-14 Sealing material 20 Wafer cassette 21 Pod door 31 Port door 32 Elevating shaft 33 Port skirt 33A Lower engaging peripheral portion of port skirt 33B Upper engaging peripheral portion of port skirt 33b, 34 Sealing material 35 Guide rod 36 Engaging roll 37 Hanging device as urging device 40 Lock mechanism A Sealed space

──────────────────────────────────────────────────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. Government Masaki Shibanuma (56) References Special Table Hei 4-505234 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) H01L 21/68

Claims (4)

(57) [Claims] 1. An object provided in a main body case for carrying in and out an object to be processed.
A pod with an opening flange that is placed on a port plate that forms a carry-out port and covers the port, a pod door that can close the opening of the pod, and that is supported in the main body case so as to be able to move up and down and is connected to the port plate at the time of the highest movement A mechanical interface device for engaging and closing said port, said port door transporting said pod door from within said pod to a body case and vice versa, said port door being movable up and down a predetermined height A movable port having a cylindrical space formed therein and having a lower engaging peripheral portion capable of airtightly engaging the lower surface of the port door and an upper engaging peripheral portion capable of airtightly engaging the lower surface of the port plate. skirt,
An urging device is provided on the port door or on a member that moves up and down together with the port door to urge the port skirt toward the port plate. The port door hermetically engages the lower engagement peripheral portion. Until
The pod door and the port are driven down by a predetermined height.
The sealed space where the door communicates with the inside of the pod is
Partition between the plate and the inner circumference of the port plate
Exhaust port opening on the inner surface and N
₂ using the air supply port connected to the gas source,
A mechanical interface device for injecting N ₂ gas into a device. 2. The urging device, which is a suspending device held by a port door, has a suspending line having a coil spring at one end and an engaging roller with which a non-coil spring portion of the suspending line engages. The end of the suspension wire on the coil spring side is locked by a locking pin provided on the port door, and the non-coil spring portion is engaged with the engagement roller and hangs down to the lower engagement portion of the port skirt. 2. The mechanical interface device according to claim 1, wherein the coil spring is locked at the joint and the coil spring is preloaded. 3. A biasing device comprising a plurality of preload coil springs interposed between a base fixed to a support shaft of a port door and a lower engaging portion of a port skirt. The mechanical interface device according to claim 1. 4. After the pod is set on the port plate, a port door is lowered a predetermined height, after the sealed space formed, the predetermined time N ₂ gas from the air inlet open to the exhaust port or oxygen concentration injected until a predetermined value or less, the discharge
The mechanical interface device according to any one of claims 1 to 3, wherein the port is closed, and then the port door is lowered to the workpiece transfer position.