JPH0582624A - Mechanical interface device - Google Patents

Abstract

PURPOSE:To replace gas inside a pod without installing a special shielding structure outside a port door by lowering a pod door with the port door being airtightly fit in with a port plate for opening the pod. CONSTITUTION:Between a port door 31 and pod door 21, a space X where a pod door 21 goes up and down X is provided and the pod door 21 is raised and lowered by fixing devices 71-80 housed in the pod door 21 and a fitting recessed section 10B. Because of this structure, when the inside of a pod POD 10 is replaced with the same gas atmosphere as that of a main body case 1, the pod door 21 is lowered with the port door 31 being airtightly fit in with a port plate 3 and then an opening of the pod POD 10 can be opened and therefore a shielding structure such as a bellows is unnecessary. The pod door 21 goes down onto projections 31D of the port door 31 and forms a space with the port door 31. Therefore, the lower face, etc., of the pod door 21 can be cleaned at the time of N2 gas purge.

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, but there is a problem that it is too expensive including maintenance. Since there is a limit to the reduction of the contamination level of particle contamination, for example, Japanese Patent Laid-Open No.
A standardized mechanical interface device (SMIF device) has been developed as disclosed in the publication 0-143623.

This SMIF device, for example, as shown in FIG. 4, contains a wafer processing device (not shown), is filled with clean air, and has a main body case 1 and a portable type box (hereinafter It includes a pod POD) 10 and a carrier device 30. Body case 1 of the device body
Ports (loading / unloading port of the wafer cassette 20) 4 are formed on the top plate 2 by the port plate 3, and the pod POD 10 having the grip portion 10A is placed on the port plate 3. The pod POD 10 has a shape having a flange 12 having an annular portion 12 a around the opening 11. The transfer device 30 in this example is an elevating device, and the wafer cassette 20 is placed on an elevating table 31 supported by an elevating shaft 32 to elevate and lower. , The port plate 3 is abutted or fitted from below to seal the port 4 to the outside of the main body case 1, and the base 21 of the wafer cassette 20 on the port door 31 is the opening 1 of the pod POD 10.
The opening 11 is sealed by abutting on the peripheral portion of 1. This stand 2
Hereinafter, 1 is referred to as a pod door. Reference numeral 13 is a sealing material, which seals between the opening 11 of the pod POD 10 and the pod door 21, sealing material 14 seals between the flange 12 of the pod POD 10 and the port plate 3, and sealing material 15 seals the port plate 3. And the port door 31 are sealed. 40 is a lock mechanism having a lock lever 41 driven by a geared motor (not shown),
It serves to push down the flange 12 of the pod POD 10 onto the port plate 3. In this example, after the unprocessed wafer W is transferred onto the port door 31 from another location (not shown), the pod POD 10 is mounted on the port plate 3 and fixed by the lock lever 41. The port door 31 is lowered to the transfer position. When the port door 31 descends to the transfer position, a transfer device (not shown) transfers the wafer cassette 20 on the port door 31 to the processing machine.

By the way, conventionally, the particle contamination of the wafer W has been a problem, but as the density of the semiconductor integrated circuit is increased, the influence of the natural oxide film on the wafer surface caused by oxygen in the air begins to become a problem. In order to prevent the growth of this natural oxide film, it becomes necessary to move and transfer the wafer W in an inert gas (N ₂ gas) atmosphere.
An N ₂ gas atmosphere in which the concentrations of O ₂ and H ₂ O are 10 ppm or less is required.

When using the above-mentioned SMIF device,
And N ₂ gas atmosphere of air in the main body case 1 is replaced with N ₂ gas, pod POD10 is the pod POD10
There each time is set on the top plate 2 of the casing 1, so that the N ₂ gas atmosphere to replace the interior with N ₂ gas.

The method of this gas replacement will be described below with reference to FIG.

In the SMIF device of FIG. 5, the pod door 21 incorporates a fixing means as shown in FIG. 6,
It is transported from device to device with the pod POD.

In FIG. 6, the pod door 21 is a hollow frame. Reference numeral 61 denotes a cam, and the cam shaft 62 extends into the port door 31, is housed in the port door 31, and is driven by a motor (not shown). Reference numeral 63 denotes a plate-shaped lock arm that is rotatable about a shaft 63a as a fulcrum and is supported by a cantilever so as to be movable back and forth in the longitudinal direction.
Reference numeral 64 is a restraint plate that hangs from the upper bottom surface of the pod door 21 and engages with the upper surface of the lock arm 63. 10B is a fitting recess formed on the inner peripheral surface of the opening 11 of the pod POD10.

In this structure, the cam 61 has a special cam surface, and when the cam 61 rotates, the lock arm 63 is displaced toward the engaging recess 10B in the direction of the arrow in the figure, and the tip end thereof is fitted into the fitting recess 10B. Engage with.

Now, it is assumed that the pod POD 10 is transferred from another place onto the port plate 3 and the inside is in a clean air atmosphere. In this state, the opening 1 of the pod POD10
The seal material 13 is provided between the pod P1 and the pod door 21.
The sealing material 14 is provided between the flange 12 of the OD 10 and the port plate 3, and the port plate 3 and the port door 31 are also provided.
It is sealed with a material 15 for sealing the gap between and. When the inside of the pod POD 10 is replaced with N ₂ gas, the lock by the lock arm 63 is released, and then the lifting shaft 3 is moved.
2 is slightly lowered to separate the pod door 21 from the opening surface of the pod POD 10, and the space where the gas supply port 3A and the gas exhaust port 3B are open (the space between the port 4 and the peripheral side surface of the port door 31) A To communicate with the inside of the pod POD10.
In fact, the pod POD10 is placed in the port plate 3, N ₂ supply side valve connected to the gas cylinder V1, opening the exhaust valve V2, N ₂ gas into the space A from the gas supply port 3A Is press-fitted to discharge dust and the like attached to the surfaces of the pod door 21 and the port door 31 exposed to the outside air from the gas exhaust port 3B to the outside of the apparatus. Therefore, as described above, when the pod door 21 is lowered integrally with the port door 31 so that the space A communicates with the inside of the pod POD 10, the N ₂ gas delivered from the air supply side valve V1 through the gas air supply port 3A. Enters the pod POD10 and discharges the air in the pod POD10 to the outside of the apparatus through the gas exhaust port 3B, and the inside of the pod POD10 is filled with N ₂ gas. When the elevating shaft 32 is lowered as described above, the flange portion 31A of the port door 31 separates from the lower surface of the port plate 3, so that the space A not only communicates with the inside of the pod POD10.
Since the air in the POD 10 may communicate with the inside of the body case 1 (which is already in the N ₂ gas atmosphere), the air inside the POD 10 may enter the inside of the body case 1.
0 is provided to prevent this.

[0011]

As described with reference to FIG. 5, in the method of lowering the pod door 21 integrally with the port door 31 by slightly lowering the raising / lowering shaft 32, the space A inside the pod POD 10 is reduced. Since it communicates with the inside of the main body case 1 via this, there is a problem that a special sealing mechanism is required to prevent this.

The present invention has been made to solve this problem, and provides a mechanical interface device capable of performing gas replacement in a pod without providing a special seal structure outside the port door. With the goal.

[0013]

In order to achieve the above-mentioned object, the present invention is, in claim 1, mounted on a port plate which is provided in a processing body case and which forms a port for loading / unloading an object to be processed. A pod that covers the port, a pod door that can be fitted into the opening of the pod to be closed, means for fixing the pot door in the opening of the pod, a pod door that can be lifted and supported in the body case. A port door that engages with the port plate when closing and closes the port, and the port plate has a gas supply port and a gas exhaust port that open to the peripheral surface of the port, and the port door is the pod door. In the mechanical interface device for transporting from the inside of the pod to the inside of the body case and vice versa, the fixing means is provided on the inner peripheral surface of the opening of the pod. It has a lock arm that moves forward and backward with respect to the formed arm fitting portion, and a mechanism that moves the lock arm forward and backward and moves up and down, and the port door is configured to define a vertical space for the pod door between the port door and the pod door. ..

According to the present invention, the rotary screw shaft, the plate-shaped guide pressing portion extending in the radial direction, the cylindrical cam surface, the conical cam surface continuous below the cylindrical cam surface, and the radial direction from the top of the cylindrical cam surface. A non-rotating cam that is integrally movable with a plate-shaped guide pressing portion that extends outwardly and that is externally fitted and screwed onto the rotary screw shaft, guides the forward / backward movement of the lock arm, and is urged upward by the first elastic body. Arm guide that engages with the lower surface of the guide retainer, a guide shaft that vertically guides the arm guide, a second elastic body that biases the lock arm toward the fixing screw shaft, and a protrusion from the port door. A rotary shaft that extends into the rotary screw shaft and engages with the rotary screw shaft by spline engagement so as to be vertically movable relative to the rotary screw shaft, and a motor that is disposed in the port door and drives the rotary shaft. Axially supported And configured to press engagement with the cam surface of the cam at the trochanter.

In the third aspect, the port door is provided with a sensor for detecting the pod position.

According to the present invention, a plurality of spacer projections are formed on the surface of the port door facing the pod.

[0017]

In the present invention, the elevation space of the pod door is defined between the port door and the pod door, and the fixing means built in the pod door can raise and lower the pod door. When the gas atmosphere is replaced with the same gas atmosphere, the pod door can be lowered and the opening of the pod can be opened while the port door is airtightly engaged with the port plate.

[0018]

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

In FIG. 1, the opening 1 of the pod POD 10
A plurality of fitting recesses 12B are formed on the inner peripheral surface of the fitting 1. The engaging ends of the lock arms 71, which will be described later with reference to FIG. 2, are fitted into the fitting recesses 12B, and the pod door 21 becomes the pod. It is held by the POD 10 and hermetically closes the pod POD 10. In this state, the port door 31 defines the pot door lifting space X between itself and the pot door 21,
On the upper surface of the port door 31, three spacer protrusions 31D arranged in an equilateral triangle are formed. The port door 31 is also provided with a sensor (touch sensor, proximity sensor, etc.) S that can detect the vertical position of the pod door 21.

Sealing grooves 3a and 3b extending in the circumferential direction are formed in the portion of the surface of the port plate 3 facing the flange 12.
Are formed at small intervals in a direction orthogonal to the circumferential direction. Sealing materials (O-rings) 51a and 51b are fitted in the sealing grooves 3a and 3b, and both sealing materials form an annular groove-shaped space Y on the surface of the port plate. The port plate 3 is further formed with a passage hole 3C having one end opening to the surface of the port plate 3 from between the seal grooves 3a and 3b and the other end opening to the outer surface of the port plate 3 and a gas hole. An air supply port 3A and a gas exhaust port 3B are formed. The passage hole 3C is connected to a vacuum pump (not shown) through a pipe 3D.

Next, referring to FIGS. 2 and 3, the pod door 2
The fixing means built in 1 will be described.

In both figures, the pod door 21 is a hollow frame, and a peripheral wall 21A facing the inner peripheral surface of the opening 11 of the pod POD 10 is formed with a window 21B having a predetermined height for the lock arm 71 to move in and out. ing. Reference numeral 72 denotes a screw shaft, which is vertically supported by a bearing 73. The screw shaft 72 has a spline hole 7 that opens toward the lower surface.
2A, and the end of a rotary shaft 74 extending vertically from the center of the port door 31 is spline-engaged with the spline hole 72A so as to be vertically movable. Port door 31
A drive mechanism (motor M in this example) for driving the rotating shaft 74 is built therein. It is a 75 non-rotating cam and is externally fitted and screwed to the screw shaft 72. The cam 75 has a shape integrally including a cylindrical cam surface 75A, a conical cam surface 75B continuous below the cylindrical cam surface, and a plate-shaped guide pressing portion 75C extending in the radial direction from above the cylindrical cam surface. .. A guide member 76 has a flat slide space 76A in which the plate-shaped lock arm 71 can slide, and is vertically movably guided by two vertically oriented guide shafts 77 and two coil springs 78. The coil spring 79 is biased upward and is biased toward the screw shaft 72 by the coil spring 79. The coil spring 78 is interposed on the guide shaft 77. 80 is a bearing. The lock arm 71 is an engaging portion whose one end 71A engages with the fitting recess 10B, and has a rotator (roller) 71B which engages with the cam surface of the cam 75 pivotally supported at the other end.

In this state (locked state), when the rotating shaft 74 is rotated rightward, the cam 75 is displaced upward so that the trochanter 71B is conical from the cylindrical cam surface 75A. It comes to engage with the cam surface 75B. When the trochanter 71B comes into engagement with the conical cam surface 75B, the lock arm 71 retracts to the screw shaft 72 side, and the engaging end portion 71A passes from the fitting recess 10B through the window 21B and into the pot door 21. Evacuate and unlocked.

When the rotary shaft 74 is rotated counterclockwise in the illustrated state, the screw shaft 72 descends relatively to the cam 75, so that the pod door 21 moves downward in the ascending / descending space X,
It is placed on the protrusion 31D of the port door 31. Pod door 21
It is detected by the sensor S that the above has descended onto the protrusion 31D, and the motor M is stopped by the signal of this sensor S.

The gas inlet 3A and the gas outlet 3B are used for replacing the inside of the pod POD10 with N ₂ gas, and the gas inlet 3A is connected to an N ₂ gas cylinder (not shown) through a pipe. It Further, the inside of the main body case 1 is in a N ₂ gas atmosphere and is constantly pressurized.

In this embodiment, when the pod POD 10 is transferred from the outside of the apparatus onto the port plate 3 of the main body case 1, the groove-shaped space Y formed by both the sealing materials 51a and 51b becomes the lower surface of the flange 12 of the pod POD 10. Closed in. When the transfer of the pod POD10 is completed, a vacuum pump (not shown) is driven. When the vacuum pump is driven, the inside of the pipe 3D becomes a negative pressure, so the air in the closed groove space Y is exhausted to the outside through the pipe 3D, and the groove space Y is discharged.
Becomes negative pressure. When the groove space Y has a negative pressure, the pod PO
Since the suction force acts on the flange 12 of D10,
The flange 12 of the pod POD10 has sealing materials 51a, 5a.
It is displaced toward the port plate 3 side against the elastic force of 1b, and the sealing materials 51a and 51b are sandwiched between the plate 1 and the port plate 3.

Next, in order to replace the inside of the pod POD10 with N ₂ gas, as described above, the rotary shaft 74 is rotated right, for example, to release the locked state by the lock arm 71, and then the rotary shaft 74 is rotated left. , The pot door 21 is lowered onto the port door 31.

When the pot door 21 descends toward the port door 31, the pod POD10 opens and the pod PO
The inside of D10 communicates with the space A between the gas supply port 3A (the space between the port 4 and the peripheral side surfaces of the pod door 21 and the port door 31) A, but the port door 31 closes the lower surface of the port plate 3. Since the space between the paw plate 3 and the flange 12 is hermetically closed by the sealing members 51a and 51b, the space A is hermetically shielded both outside the main body case 1 and inside the main body case 1. ing. When the sensor S detects that the pod door 21 has descended onto the protrusion 31D, the gas supply port 3A releases N ₂
Inject gas. The injected N ₂ gas flows into the pod POD 10 from the space A to expel the air inside, and a part of the N ₂ gas flows through the gap between the pod door 21 and the port door 31 to the gas exhaust port 3B.

As described above, in this embodiment, the port door 3
1 and the pod door 21, an elevation space X for the pod door 21 is defined, and the fixing means 71 to 80 and the fitting recess 10B built into the pod door 21 can drive the pod door 21 up and down. POD1
When the inside of 0 is replaced with the same gas atmosphere as the inside of the main body case 1, the pod door 21 can be lowered to open the opening of the pod POD 10 while the port door 31 is hermetically engaged with the port plate 3. Therefore, the sealing structure such as the bellows 50 described above becomes unnecessary.

Further, in this embodiment, the pod door 21 descends onto the projection 31D of the port door 31, and the port door 31
Since a gap is formed between the pod door 21 and the port door 31, it is possible to purify the lower surface of the pod door 21 and the upper surface of the port door 31 during the N ₂ gas purge.

The main body case 1 may be a stocker of a wafer cassette in an N ₂ gas atmosphere.

[0032]

As described above, according to the present invention, when the gas in the pod is replaced, the port door that hermetically closes the port from the body case side is left as it is, and only the pod door is separated from the pod opening. Because you can
It is possible to replace the inside of the pod with the same atmosphere as the inside of the main body case without adding a special seal structure to the outside of the port door.

[Brief description of drawings]

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

FIG. 2 is a left half sectional view of the pod door in the above embodiment.

FIG. 3 is a view showing a guide member in the above embodiment.

FIG. 4 is a diagram schematically showing an example of a conventional SMIF device.

FIG. 5 is a diagram schematically showing another example of a conventional SMIF device.

6 is a vertical cross-sectional view of the pod door in the conventional example of FIG.

[Explanation of symbols]

 1 Main Body Case 3 Port Plate 3a, 3b Seal Groove 3A Air Supply Port 3B Exhaust Port 3C Passage Hole 4 Port 10 Pod POD 10B Fitting Recess 11 Pod POD Opening 12 Pod POD Flange 13, 15 Sealing Material 20 Wafer Cassette 21 Pod Door 31 Port Door 31A Port Door Collar 31D Protrusion 32 Lifting Shafts 51a, 51b Sealing Material 71 Lock Arm 72 Screw Shaft 74 Rotating Shaft 75 Cam 75A Cylindrical Cam Surface 75B Conical Cam Surface 75C Pressing Part 76 Guide Member 77 Guide Shaft 78, 79 coil spring A space X lifting space Y grooved space

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mitsuhiro Hayashi, 100 Takegahana-cho, Ise-shi, Mie Shinko Electric Co., Ltd. (ISE) Tetsuhei Yamashita 100, Takegahana-cho, Ise-shi, Mie Shinko Electric Co., Ltd. (72) Inventor, Makoto Murata, 100, Takegahana-cho, Ise-shi, Mie Shinko Electric Co., Ltd., Ise Works (72) Inventor, Miki Tanaka, 100, Takegahana-cho, Ise-shi, Mie Shinko Electric Co., Ltd. (72) Inventor Moriya Hiya 100, Takegahana Town, Ise City, Mie Prefecture Shinko Electric Co., Ltd.

Claims (4)

[Claims] 1. A device provided on the main body case for carrying in an object to be processed,
A pod that is placed on a port plate that forms a carry-out port and covers the port, a pod door that can be fitted in the opening of the pod and can be closed, and the pot door provided in the pot door and fixed in the opening of the pod. And a port door that is liftably supported in the body case and that engages with the port plate to close the port at the time of the maximum rise, and the port plate has a gas supply port that opens to the peripheral surface of the port. And a gas exhaust port is formed, and the port door conveys the pod door from the inside of the pod to the inside of the body case and vice versa.The fixing means is formed on the inner peripheral surface of the opening of the pod. A lock arm that moves forward and backward with respect to the arm fitting part that has been moved, and a mechanism that moves the lock arm forward and backward and moves up and down. The door door defines a space for raising and lowering the pod door between the door door and the pod door. 2. A rotary screw shaft, a cylindrical cam surface, a conical cam surface which is continuous under the cylindrical cam surface, and a plate-shaped guide pressing portion which extends in the radial direction from above the cylindrical cam surface. A vertically rotatable non-rotating cam that is externally fitted and screwed to a rotating screw shaft, an arm guide that guides the forward / backward movement of the lock arm, and is urged upward by the first elastic body to engage with the lower surface of the guide pressing portion, A guide shaft that guides the arm guide up and down, a second elastic body that biases the lock arm toward the fixed screw shaft, and a member that projects from the port door and extends into the rotary screw shaft to face the rotary screw shaft. The lock arm is provided with a rotary shaft which is spline-engaged so as to be vertically movable and a drive mechanism which is arranged in the port door and drives the rotary shaft.The lock arm is a rotator pivotally supported at one end on the cam surface of the cam. Special feature of pressure contact The mechanical interface device according to claim 1, which is a characteristic. 3. The mechanical interface device according to claim 1, wherein the port door is provided with a sensor for detecting a pod position. 4. The surface of the port door facing the pod,
The mechanical interface device according to claim 1, wherein a plurality of spacer protrusions are formed.