JPH0476882B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a cleaning device used for storing objects such as semiconductor wafers in a clean state.

[Conventional technology]

Semiconductor wafers need to be stored in extremely dust-free locations to improve the precision of semiconductor devices, but conventionally, to protect semiconductor wafers from dust, the entire area where they are handled has been cleaned. There is.

[Problem that the invention seeks to solve]

When cleaning the entire warehouse or processing room where semiconductor wafers are handled, there is a limit to how much cleaning can be done and the equipment becomes large, which is uneconomical.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a cleaning device that cleans a storage area for objects such as semiconductor wafers.

[Means for solving problems]

That is, the cleaning device of the present invention includes a pressure-feeding means (fan 40) for pumping gas, which is vertically installed in the center of the space to be cleaned (accommodation section 4), and a space between the pressure-feeding means and the fan 40. a discharge pipe 16 through which the gas is fed under pressure through a pipe connected therebetween, and the gas is discharged radially into the space;
A plurality of storage shelves 10 are installed in the height direction with this discharge pipe in the center at intervals greater than the height that can store items to be stored (cassettes 9, semiconductor wafers, etc.), and a storage space of each storage shelf. and the discharge pipe so as to surround the discharge pipe, and while passing the gas discharged from the discharge pipe,
A filter 14 that forms clean gas, a surrounding wall (punched metal 21) that is installed to surround the storage shelves and through which the clean gas that has passed between the storage shelves can pass, and installed on the peripheral surface side of this surrounding wall. suction portions 18 and 20 for receiving the clean gas, and suction means (fans 40,
44).

[Effect]

In the cleaning device of the present invention, a discharge pipe is installed vertically in the center of the space to be cleaned, and a pressure-feeding means for pressure-feeding gas through the pipe is connected to the discharge pipe. The gas is discharged radially from the discharge pipe. A plurality of storage shelves are formed in the discharge pipe at intervals greater than the height that can store the stored items in the height direction, and the discharge pipe is placed between the storage space of each storage shelf and the discharge pipe. A filter is installed in a surrounding manner. Therefore, the gas discharged from the discharge pipe is purified through the filter, and is supplied as purified gas from the discharge pipe side to the space between each storage shelf independently.

In addition, an enclosing wall is provided around the storage shelf through which clean gas can pass, and an intake section is provided on the peripheral surface of this enclosing wall. A suction means for forcibly sucking in a laminar flow of cleaning gas is connected to the suction means. Therefore, after passing through the space between the storage shelves, the purified gas being pumped is forcibly drawn into the intake section on the back side of the enclosure wall through the intake means, and remains within the space between the storage shelves. Instead, a constant laminar cleaning gas flow is formed radially from the discharge pipe to the surrounding wall at every interval between the storage shelves, thereby cleaning the storage space.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

(First Embodiment) FIGS. 1 to 6 show a first embodiment of the cleaning device of the present invention.

In FIG. 1, the exterior body 2 includes a storage section 4 that forms a storage space for storing objects such as semiconductor wafers, and a transport section 6 that carries the objects into and out of the storage section 4. It is installed separately.

A cylindrical support 8 is rotatably installed in the center of the storage section 4, and a cassette 9 containing a plurality of semiconductor wafers as objects to be stored is installed on the peripheral wall of the support 8. A plurality of disc-shaped storage shelves 10 are installed in a plurality of stages, and a discharge section 12 is provided as a clean gas flow mechanism for discharging air within the storage space between the storage shelves 10. A filter 14 is attached to the section 12 to purify the discharged air. Therefore, purified air can be discharged into the storage section 4 via the filter 14 from the discharge section 12 provided between the storage shelves 10 installed in multiple stages. A discharge pipe 16 is installed in the center of the support column 8 to uniformly force clean air to the discharge section 12. In addition, the storage section 4 and the conveyance section 6 are provided with intake sections 18 and 20 that suck air from the support column 8, and storage shelves 1 and 2 are provided on the intake side of each intake section 18 and 20.
A punching metal 21 is arranged to surround 0.

Therefore, the air that has been purified through the filter 14 and released into the storage section 4 passes between the storage shelves 10 installed on the peripheral wall of the support column 8, and then is sent to the storage section 4 and the transport section 6. The air is sucked into the air intake portions 18 and 20 provided.

A ventilation section 23 that is open to the outside air is provided on the upper surface of the exterior body 2, and air is drawn into the exterior body 2 through the ventilation section 23 during the cleaning operation.

The transport section 6 is equipped with a transport mechanism 22 that carries the cassettes 9 into and out of the storage section 4. This transport mechanism 22 is provided with a transport arm 24 that grips the cassette 9 and transports it in the front-rear direction.
A moving table 26 is installed at the bottom of the transport arm 24 on which the cassette 9 to be transported is temporarily placed. These transfer arm 24 and moving table 26
can be automatically raised and lowered to a desired height by a lifting mechanism 28. And on the side wall of the exterior body 2,
A carry-in/out port 30 is provided for carrying out the cassette 9 carried out from the storage section 4 to the outside.

2 to 4 show a clean air circulation mechanism in the cleaning device shown in FIG. 1. FIG.

In FIG. 2, a base part 32 is provided inside the exterior body 2, and a bearing part 34 attached to this base part 32 and a bearing part 36 attached to the ceiling part of the exterior body 2 are connected to each other. A support column 8 is rotatably installed in between, and a discharge pipe 16 and a piping section 38 for pressure-feeding air are arranged inside the base section 32.

As shown in FIG. 3, this piping section 38 connects the discharge pipe 16 and the intake sections 18, 20, and as shown in FIG. 16, the clean air is injected from the discharge part 12 as indicated by arrows A and B, and is sucked into the suction parts 18 and 20 by the suction force of the fan 40, which constitutes the suction means. The discharge air is again supplied to the discharge pipe 16 via the filter 42, and a portion of the surplus air is discharged to the outside as shown by arrow C via the fan 44.

5 and 6 show the specific structure of the transport mechanism 22. FIG.

In FIG. 5, the transport mechanism 22 is a lifting mechanism 28.
A pair of gripping pieces 46 for gripping the cassette 9 are attached to the transport arm 24. The transport arm 24 moves in its front-rear direction, and the interval between the gripping pieces 46 is controlled in a direction perpendicular to the direction of movement of the transport arm 24.

The lifting mechanism 28 includes a wire 52 between a wire pulley 48 installed on the ceiling side of the exterior body 2 and a wire pulley 50 installed on the base portion 32 side of the exterior body 2.
The transport mechanism 22 is fixed to a wire 52.

Further, the moving table 26 is configured to be movable in a direction orthogonal to the moving direction of the transfer arm 24, as shown by the two-dot chain line in FIG.

A transport port 56 for loading and unloading the cassettes 9 is opened in the partition wall 54 that partitions the storage section 4 and the transport section 6. An opening/closing door 60 that is automatically opened and closed by a device 58 is installed.

The operation of the above configuration will be explained.

When air is force-fed from the fan 40 to the discharge pipe 16, the air is injected from the discharge pipe 16 into the support column 8, purified by the filter 14, and sent to the discharge part 12.
It is discharged from.

This discharged air flows through the space between the shelves 10,
It passes between the cassettes 9 storing a plurality of semiconductor wafers and reaches the air intake sections 18 and 20. Intake part 1
Negative pressure is applied to 8 and 20 by fans 40 and 44, and a constant flow of discharged air is obtained by the interaction between the discharge pressure and the intake pressure, and the cassette 9 is placed inside.

As a result, dust is effectively prevented from adhering to the cassette 9 and the semiconductor wafers stored therein.

In this case, since the clean air as a clean gas is discharged in the radial direction from the center of the shelf 10 on which the cassettes 9 are placed, there is no accumulation of clean air and the adhesion of dust is prevented.

In particular, since the interior of the exterior body 2 is separated into the storage section 4 and the conveyance section 6, and the conveyance section 6 is installed on the downstream side of the discharged air, dust such as friction powder generated in the conveyance section 6 is stored. There is no flow into the storage section 4, and the cleanliness of the storage section 4 is maintained at a high level.

Next, storage and removal of the cassette 9 will be explained.

As shown by the two-dot chain line in FIG.
A moving table 26 is made to protrude outside in the direction shown by arrow D from a loading/unloading port 30 provided on the side surface of the exterior body 2, and the cassettes 9 to be stored are placed thereon.
With the cassette 9 placed thereon, the moving table 26 is moved into the transport section 6 and stopped at a predetermined position. In this case, when the movable table 26 is moved inward, its rear portion protrudes in the direction of arrow E.

Here, the transport arm 24 is moved rearward, the gripping pieces 46 are expanded, and the transport arm 24 is lowered by the lifting mechanism 28, and the cassette 9
After the gripping piece 46 faces the side surface of the gripping piece 46,
The cassette 9 is gripped by the gripping pieces 46.

In this state, the transport arm 24 is moved upward by the lifting mechanism 28 and stopped at the position of the transport port 56, and the opening/closing door 60 is opened.
from the transport port 56 to a specific position on a specific shelf 10. In this case, the blank portion of the shelf 10 to be placed on the shelf 10 faces the transport port 56 by rotation of the support 8.

The transport arm 24 located on the top surface of the shelf 10 is
Move the cassette 9 downward together with the cassette 9.
is brought into contact with the top surface of the shelf 10 to open the gripping piece 46,
Release the grip. Then, the transport arm 24 is moved upward by the elevating mechanism 28, and at the same time, the transport arm 24 is moved backward, and at this time, the gripping piece 46
return it to the specified position.

After the loading of the cassette 9 is completed and the transport arm 24 is moved back, the opening/closing door 60 is closed.

In addition, when carrying out the cassette 9 placed on the shelf 10, the cassette 9 to be carried out is moved to the moving table 26 by an operation opposite to the carrying-in operation, and the cassette 9 is moved to the moving table 26. It shall be carried out from the carrying-out entrance 30.

When loading and unloading such a cassette 9, the support 8
Air is pumped in from the container to keep the storage section 4 clean.

(Second Embodiment) FIGS. 7 to 10 show a second embodiment of the cleaning device of the present invention, in which the same parts as in the first embodiment are given the same reference numerals.

That is, as shown in FIG. 7, the cleaning device of this embodiment has a storage section 4 and a conveyance section 6 configured in a non-separated state inside a cylindrical exterior body 2. A transport mechanism 22 is installed around 4.

In this embodiment, the screw shafts 59, 62, 64 of the elevating mechanism 28 of the conveying section 6 are vertically disposed along the inner wall of the exterior body 2 at positions displaced by a certain angle,
A support arm 66 is movably attached to each screw shaft 59, 62, 64, and a support frame 68 is fixed to each support arm 66 concentrically with the shelf 10. An annular moving table 70 is supported, and a transfer arm 24 is movably installed on the outside thereof.

As shown in FIG. 8, the air indicated by the arrow F is force-fed from the pressure-feeding means installed below to the support 8 of the storage part 4, and the air is forced into the support 8 of the storage part 4, and the air is forced into the support 8 of the storage part 4, as shown by the arrow F.
The pressurized air shown by the arrow F is discharged through the second filter 14 in the circumferential direction of the support column 8.

9 and 10 show specific structures of the transport mechanism 22 and the lifting mechanism 28. FIG.

9 and 10, the screw shaft 59,
An annular support frame 68 is integrally fixed to the tip of the support arm 66 attached to the support arms 62 and 64, and rails 72 and 74 are provided on the inner and outer wall surfaces of the support frame 68, respectively. There is.

A moving table 70 is rotatably supported on the rail 72 via a plurality of rollers 76 and 78 attached to the side surface thereof. Further, a gear 80 concentric with the movable base 70 is attached to the side of the movable base 70, and the gear 80 is driven by a motor 82 fixed to the lower surface of the support frame 68.
4 are engaged. That is, the motor 82
As a result of the rotation, the moving table 70 rotates around the storage shelf 10.

A rotating frame 86 to which the transport arm 24 is attached is rotatably supported on the rail 74 via a plurality of rollers 88 and 90, and a gear 92 attached to the rotating frame 86 is fixed to the lower surface of the support frame 68. A gear 96 driven by a motor 94 is engaged.

Gears 98, 1 are provided at the lower ends of the screw shafts 62, 64.
A gear 102 driven by a rotary drive device such as a motor (not shown) is meshed with these gears 98 and 100, and the screw shafts 62 and 64 are rotated by the rotation of the gear 102. , support frame 68 with support arm 66
moves in the vertical direction as shown by arrow G.

Further, the transfer arm 24 is connected to the arm support frame 1
04, it is supported so as to be rotatable in the horizontal direction as shown by arrow H in FIG. 9 and movable in the front and back direction as shown by arrow I. Note that 106 is a pedestal provided at the loading/unloading entrance 30.

The operation will be explained based on the above configuration.

The air supplied from the fan 40 to the inside of the support column 8 is purified by the filter 14 and discharged from the discharge section 12. This discharged air flows through the space between the storage shelves 10, and the plurality of semiconductor wafers are passed through the space between the storage shelves 10. It passes between the stored cassettes 9 and reaches the intake sections 18 and 20. As a result, dust is effectively prevented from adhering to the cassette 9 and the semiconductor wafers stored therein. Also in this embodiment, since the conveyance section 6 is installed on the downstream side of the discharged air, dust such as friction powder generated in the conveyance section 6 is pushed toward the peripheral wall of the exterior body 2, and the dust inside the storage section 4 is Cleanliness will be achieved.

Next, in order to carry in the cassette 9 in this case, the cassette 9 is placed in the vicinity of the carry-in/outlet 30 by means of a conveying means (not shown), and then the cassette 9 is placed in the vicinity of the carry-in/out entrance 30, and the cassette 9 is placed in the vicinity of the carry-in/out entrance 30 by a conveying means (not shown), and the conveying arm 24 is moved as shown by the two-dot chain line in FIG. Grip the cassette 9 with the gripping piece 46 and take it into the exterior body 2, rotate the transport arm 24 as shown by arrow H while gripping the cassette 9, and direct the gripped cassette 9 toward the storage shelf 10. , further moves the transport arm 24 forward as indicated by arrow I.

That is, the rotating frame 86 is moved to a predetermined position by the rotation of the motor 94, and the gear 102 is rotated to raise and lower the support frame 68 together with the support arm 66, thereby adjusting its vertical position. The transport arm 24 is rotated to protrude from the carry-in/out port 30, the gripping piece 46 grips the cassette 9, and the cassette 9 is moved into the exterior body 2 together with the transport arm 24.

At this time, the cassette 9 is temporarily placed on the moving table 70.

Then, the transport arm 24 moves the gripping piece 46 to the first position.
As shown by the two-dot chain line in FIG. 0, the cassette 9 is transferred while being gripped, and moved to the placement position on the shelf 10. In this state, the lifting mechanism 28 is operated to move the transport arm 24 slightly downward together with the support frame 68, and after placing the cassette 9 on the shelf 10, the gripping piece 46 is released and the transport arm 24 is moved again. After moving slightly upward, the gripping piece 46 is returned to its original position.

In this case, the placement position of the storage shelf 10 is selected by fixing the shelf 10 and rotating the movable table 70 and the rotating frame 86, unlike the rotation of the shelf 10 in the embodiment described above.

It is assumed that the cassettes 9 are carried out from the shelf 10 by driving the transport arm 24 in a manner opposite to the carrying-in process.

〔Effect of the invention〕

As explained above, according to the present invention, storage shelves are formed in multiple stages in the height direction around the discharge pipe, and gas from the discharge pipe is disposed within the space between the storage shelves. A cleaning filter is provided, and an intake section is provided around the storage shelf through a surrounding wall, so the gas pumped by the pumping means is discharged from the discharge pipe and purified via the filter. The purified gas is supplied to the storage shelves as a clean gas, and is also forcibly sucked into the surrounding area of the storage shelf through the intake means through the surrounding wall to the intake section, so that the stored items on each storage shelf are evenly cleaned. In addition, each cleaning gas is forcibly sucked into the intake section side without interfering with each other, forming a laminar flow for each storage shelf, and the flow of cleaning gas is not hindered in any way. In addition, since there is no interference between each storage shelf, each storage shelf can be cleaned independently at each interval, and recontamination does not occur between each storage shelf, and each storage shelf can be cleaned independently. It is possible to achieve a high degree of cleaning by making the cleanliness level of the storage uniform, and the items stored in each storage shelf can be stored in a highly clean state. Therefore, it is possible to improve the storage efficiency and the removal efficiency of the stored items, and together with the radial cleaning gas flow, it is possible to contribute to high-level cleaning of the stored items.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway perspective view showing a first embodiment of the cleaning device of the present invention, FIG. 2 is a sectional view showing the structure of the storage section of the cleaning device shown in FIG. 1, and FIG. The figure is a sectional view taken along the - line of the storage section shown in Fig. 2, Fig. 4 is an explanatory view showing the clean gas flow mechanism in the cleaning device shown in Fig.
A vertical sectional view showing the structure of the storage section and the transport section in the cleaning device shown in the figure, FIG. 6 is a sectional view along the - line of the storage section and the transport section shown in FIG. 5,
FIG. 7 is a partially cutaway perspective view showing a second embodiment of the cleaning device of the present invention, FIG. 8 is an explanatory diagram showing a clean gas flow system in the cleaning device shown in FIG. 7, and FIG. 9 is a horizontal cross-sectional view of the cleaning device shown in FIG. 7, and FIG. 10 is a partially cutaway vertical cross-sectional view showing the structure of the conveyance section of the cleaning device shown in FIG. 7. 4...Storage part (storage space), 9...Cassette (stored items), 10...Storage shelf, 12...Discharge part,
14... Filter, 16... Discharge pipe, 18, 20
...Intake part, 21...Punching metal (surrounding wall),
40... Fan (pressure feeding means, suction means), 44...
…Fan (intake means).

Claims (1)

[Scope of Claims] 1. A pressure-feeding means for force-feeding gas; and a pipe vertically installed in the center of the space to be cleaned, and the gas is force-fed through a pipe connected between the pressure-feeding means and the pressure-feeding means. , a discharge pipe for discharging the gas radially into the space, and a plurality of storage shelves installed in the height direction with the discharge pipe in the center at intervals greater than a height capable of storing stored items. a filter that is installed between the storage space of each storage shelf and the discharge pipe so as to surround the discharge pipe, and forms a cleaning gas while passing the gas discharged from the discharge pipe; an enclosing wall that is installed to surround the shelves and allows the clean gas to pass through between the storage shelves; an intake section that is installed on the circumferential side of the enclosure wall to receive the clean gas; A cleaning device comprising: suction means for sucking in the cleaning gas forming a radial laminar flow for each storage shelf.