JP2001056140A - Clean room - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce an equipment cost and to decrease the generation of air circulation drive force energy, in a clean room where a one-way flow clean area and a non-one-way flow clean area are situated together. SOLUTION: Temperature is reduced to temperature, at which the thermal load of a non-one-way flow area 14 is treated, by a dry coil 36. Thereby, the temperature of the non-one-way flow clean area 14 is maintained without increasing the number of circulating times. Meanwhile, a suspension wall 34 partitions a one-way flow clean area 12 and the non-one-way flow clean area 14 from each other and prevents disturbance of an air flow at the one-way flow clean area 12. Further, air is fed to the one-way flow clean area 12 through a supply air chamber 44 for one-way flow. Thereby, air having a high temperature difference in a supply air chamber 26 is not supplied directly to the one-way flow clean area 12. A supply amount of air supplied in the supply air chamber 44 for a one-way flow by a forced draft fan 46 is regulated and mixed and air having temperature approximately equal to an area temperature is supplied to the one-way flow clean area 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a clean room for providing an appropriate environment for semiconductor manufacturing and the like.

[0002]

2. Description of the Related Art As shown in FIG.
Includes a one-way flow clean area 74 (laminar flow clean area) and a non-one-way flow clean area 76 (non-laminar flow clean area) provided in accordance with the required degree of cleanliness or the like. . And the air conditioning equipment of such a clean room 72 is generally configured as follows.

That is, the space between the ceiling slab 78 and the high-performance filter 40 mounted on the outlet of the ceiling frame 80 is defined as a plenum chamber 82, and the air circulated to the plenum chamber 82 is converted into clean air through the high-performance filter 40. It blows out to the one-way flow clean area 74 and the non-one-way flow clean area 76.

[0004] The floor of the clean room 72 is a double floor, and air flows to the underfloor space 86 through a perforated floor panel 84. On the downstream side of the underfloor space 86, a dry coil 88 is provided, and the cooled air is supplied to a plenum chamber 82 through a retan chamber 90 extending upward.
Circulates to

As described above, in order to forcibly circulate the air, a large or medium-sized circulating fan 92 is provided between the retan chamber 90 and the plenum chamber 82, or a high-size circulating fan 92 as shown in FIG. Performance filter 40
It is necessary to provide a circulation fan 96 integrated with the so-called fan filter unit 94 on the ceiling frame 80.

However, in the one-way flow clean area 74 where cleanliness and temperature and humidity requirements are strict, the high performance filter 40
The temperature of the air blown through the air must be equal to or lower than room temperature by about 1 ° C., and the temperature of the return air cooled by the dry coil 88 must be within an allowable temperature (cannot be too low).

For this reason, the temperature difference between the temperature of the air blown out from the high-performance filter 40 in the non-unidirectional flow clean area 76 in which the manufacturing equipment having a large thermal load is installed and the room temperature in the non-unidirectional flow clean area 76. From about 4 ° C. to about 6 ° C. As a result, in order to maintain the room temperature in the non-one-way flow clean area 76, the number of air conditioning circulations must be increased, and the circulation fans 92 and 96 require large power energy, which is not economical.

On the other hand, with the advance of semiconductor production technology, the space requiring high cleanliness and precise temperature and humidity control is the SMI.
The mini-environment 98 has been limitedly provided in a wafer storage container such as an F pod or a FOUP, a wafer storage, or a manufacturing apparatus.

For this reason, the class as a space of the whole clean room is 1000 to 10000, and the temperature is 23 ± 2.
The temperature and humidity are reduced to about 45 ± 5%, and the cleanness of the non-one-way flow clean area 76 has been sufficient.

However, even in such a case, the conventional method in which the number of times of air conditioning circulation is determined by the heat load processing in the non-one-way flow clean area cannot reduce the equipment cost and the power energy of the circulation fan.

[0011]

SUMMARY OF THE INVENTION In view of the above facts, the present invention has been made to reduce the equipment cost and the air circulation power energy in a clean room having a one-way flow clean area and a non-one-way flow clean area. The task is to achieve this.

[0012]

According to the first aspect of the present invention, a one-way flow clean area and a non-one-way flow clean area are provided side by side, and a single work area according to a required cleanliness level is provided. The equipment can be provided.

[0013] Air is sent to the cleaning means provided at the outlet of each area through a blowing chamber. Then, the air cleaned by the cleaning means (such as a high-performance filter) is discharged from the suction port to the discharge chamber together with the fine particles in each area. Thereby, the clean level of each area is maintained.

The air discharged into the discharge chamber is
Air conditioning is performed at a predetermined temperature and humidity by an air conditioner. The conditioned air is circulated to the blowing chamber through the circulating means, and is again cleaned by the cleaning means to maintain the clean level of each area.

Here, the temperature of the air to be air-conditioned by the air-conditioning means is reduced by the air-conditioning control means to a temperature at which the heat load of the non-one-way clean area can be processed. Therefore, the temperature of the non-one-way flow clean area can be maintained because the number of circulations is not increased. On the other hand, if this air is sent to the one-way flow clean area as it is, the condition is that the air in the one-way flow clean area blows out at the same temperature as the area or about 1 ° C. lower than the temperature in the area. Air cannot be sent to the one-way flow clean area.

For this reason, in this configuration, the dividing means separates the one-way flow clean area and the non-one-way flow clean area to prevent the turbulence of the air flow in the one-way flow clean area,
In addition, air is sent to the cleaning means in the one-way flow clean area via a one-way flow blower chamber provided independently in the blower chamber.

Therefore, in the one-way flow clean area,
Air having a large temperature difference in the blower chamber is not directly blown out. Then, by adjusting and mixing the amount of air blown from the blower chamber to the one-way flow blower chamber by the blower, air close to the area temperature can be blown to the one-way flow clean area.

According to the second aspect of the present invention, the air is sucked into the one-way flow discharge chamber independently provided in the discharge chamber, and is circulated to the one-way flow blow chamber via the retan shaft.

As described above, by completely making the air flow in the one-way flow clean area completely independent, the air temperature can be easily controlled.

According to a third aspect of the present invention, there is provided a temperature sensor provided in the one-way flow clean area, and an air volume control means for controlling an air volume of the air blowing device based on a detection result of the temperature sensor. It is characterized by.

This configuration is effective in a one-way flow clean area having a large fluctuation in heat load.

According to the fourth aspect of the present invention, the partitioning means comprises:
It is a partition wall that makes the one-way flow clean area airtight. For this reason, contamination of chemical substances and the like from the non-unidirectional flow clean area can be minimized.

According to the fifth aspect of the present invention, the partition wall is provided with an exhaust port for exhausting air in the one-way flow clean area and having a check function. Therefore, air corresponding to the amount taken into the one-way flow clean area is discharged. Therefore, the one-way flow clean area has a positive pressure, and the load does not increase even when a fan is used for the blowing means.

According to the sixth aspect of the present invention, the inflow port capable of taking in air from the non-one-way flow clean area is provided in the urethane shaft. For this reason, even if there is local exhaust exceeding the intake volume in the one-way flow clean area, the one-way flow clean area does not have a negative pressure. Does not flow into clean area.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. 1, a clean room 10 according to a first embodiment has a one-way flow clean area 1.
2 and a non-unidirectional flow clean area 14 are provided. The gratings 16 disposed on these floors are supported by support supports (not shown), whereby a space between the floor slab 18 and the floor slab 18 is defined as an underfloor chamber 20.

On the other hand, a ceiling plenum chamber 26 is formed between the ceiling frame 22 and the ceiling slab 24 in the one-way flow clean area 12 and the non-one-way flow clean area 14. The underfloor chamber 20 and the ceiling plenum chamber 26 are connected by a retan chamber 32 formed between the side wall 28 of the non-one-way flow clean area 14 and the wall 30 of the clean room 10 and discharged from each clean area. The circulated air is circulated in the order of the underfloor chamber 20, the retan chamber 32, and the ceiling plenum chamber 26.

A one-way flow clean area 1 in the center
The non-unidirectional flow clean area 14 is separated from the non-unidirectional flow clean area 14 by a hanging wall 34 that hangs down from the ceiling frame 22. Is considered.

As described above, the one-way flow clean area 12
And a non-one-way flow clean area 14 are provided in one clean room 10, so that a work area corresponding to the required cleanliness can be provided by a single facility. The hanging wall 34
Is a simple type which is allowed to hang down to around the height of the clean management target, and the lower portion is allowed to mix with air in the non-one-way clean area 14.

On the other hand, on the upstream side of the urethane chamber 32,
A dry coil 36 for cooling is provided. The dry coil 36 is controlled by an air-conditioning control unit (not shown), and returns to the ceiling plenum chamber 26 through the retan chamber 32 in order to enable heat load processing in the non-one-way flow clean area 14 in which the heat load density varies greatly depending on the manufacturing area. The temperature of the air is cooled to a temperature 8 to 10 ° C. lower than the room temperature set in the non-unidirectional flow clean area 14.

This makes it possible to cope with a change in the manufacturing layout and an increase / decrease in the thermal load, without increasing the number of air conditioning circulations.
Heat load treatment and cleanness maintenance can be realized.

A HEPA filter 40 for purifying air is provided on the ceiling frame 22 of the non-one-way flow clean area 14.
There is provided a so-called fan filter unit 52 in which the circulating fan 54 (which may be an ULPA filter) and the circulation fan 54 are integrated.
(In order to cope with planar and temporal load fluctuations in the non-unidirectional flow clean area, the fan filter unit has a variable air volume function or air in the non-unidirectional flow clean area. With the function of mixing air with the ceiling plenum chamber).

A ceiling plate is disposed on a ceiling other than the fan filter unit 52. Further, the retan chamber 32 is provided with an outside air introduction unit 42 that cleans the outside air with a HEPA filter and that introduces the outside air by performing an air conditioning process.

With this configuration, the cold air cleaned by the HEPA filter 40 is blown out to the non-one-way flow clean area 14, and the heat load treatment and the maintenance of the cleanness are economically realized.

In the ceiling plenum chamber 26 above the one-way flow clean area 12 provided in a part thereof, a one-way flow ventilation chamber 44 is provided independently and circulated to the ceiling plenum chamber 26. The cold air is prevented from flowing into the one-way flow clean area 12 as it is.

A circulating fan 45 is provided in the one-way flow blowing chamber 44, and takes in the air in the one-way flow blowing chamber 44 while taking in the air in the non-one-way flow clean area 14 from the suction port 55. The air is blown into the one-way flow clean area 12 through the HEPA filter 40. The one-way flow blower chamber 44 is provided with a push-in fan 46. In order to blow air at a set temperature to the one-way flow clean area 12, the cool air in the ceiling plenum chamber 26 is diverted as much as necessary. The air is blown into the blowing chamber 44 and mixed.

A temperature sensor 50 connected to the controller 48 is provided in the one-way flow clean area 12. Based on the detection result of the temperature sensor 50, the number of rotations of the push-in fan 46 is controlled, and the amount of air blown to the one-way flow blowing chamber 44 is controlled.

By adjusting the mixing amount of the cool air in this way, the air having the same temperature as the temperature of the one-way flow clean area 12 or about 1 ° C. lower than the temperature in the area can be supplied to the HEPA filter of the one-way flow blower chamber 44. 40 can be blown out. When control of a chemical substance is required, the upstream side of the HEPA filter 40 or the circulation fan 4 is required.
5 may be provided with a chemical filter on the suction side.

In the first embodiment, the air is circulated by the circulating fan 45 in the one-way flow blowing chamber 44. However, as in the clean room 11 shown in FIG.
Fan unit 54 for one HEPA filter 40
Filter unit 52 (FF
U) or a fan module unit (FM) in which one fan unit is arranged for several HEPA filters.
U).

In this embodiment, the number of rotations of the push-in fan 46 is controlled to adjust the amount of air mixed. However, as in the clean room 13 shown in FIG. 3, a manual damper 57 is provided on the ceiling plenum chamber 26 side. Alternatively, the opening degree of the motor damper 56 attached to the ceiling frame 22 may be controlled to adjust the amount of air mixed, or a vane may be used instead of the motor damper.

As described above, in the type in which the push-in fan is not provided, the motor damper 56 is provided on the ceiling frame 22 side in order to cope with the load variation and the load variation in the clean room, and the air flow and the mixing amount are adjusted. Adjust the temperature. When the heat load fluctuation in the one-way flow clean area is small, the mixing amount may be manually adjusted.

Next, the clean room 58 according to the second embodiment is described.
Will be described.

As shown in FIG. 4, in the second embodiment, a one-way flow clean area 12 and a non-one-way flow clean area 14 are partitioned by a partition wall 60 rising from the floor surface to the ceiling to be in an airtight state. In the underfloor chamber 20 of the one-way flow clean area 12, a one-way flow discharge chamber 62 is provided.

The air discharged from the grating 16 to the one-way flow discharge chamber 62 is sent to the one-way flow blow chamber 44 by the circulation fan 66 through the retan shaft 64. As described above, by providing the one-way flow discharge chamber 62 and the urethane shaft 64 to make the one-way flow clean area 12 an independent type, contamination by the chemical substance and the like from the non-one-way flow clean area 14 is minimized. be able to. If necessary, a chemical filter is provided on the upstream side of the HEPA filter 40 or on the suction side of the circulation fan 66. Further, a push-in fan 46 is provided on the urethane shaft 64, so that the cool air in the ceiling plenum chamber 26 can be removed as much as necessary. It is taken into the directional flow ventilation chamber 44.

Further, the partition wall 60 is provided with a check damper 68 for exhausting air in the one-way flow clean area 12 and having a check function. From this check damper 68, air corresponding to the amount taken into the one-way flow clean area 12 is discharged. For this reason, the one-way flow clean area 12 becomes a positive pressure, and the circulation fan 6
6 does not increase the load.

In the clean room 59 shown in FIG. 5, a manual damper 57 is provided on the ceiling plenum chamber 26 side. In addition, a check damper 70 and a motor damper 56 that can take in air from the non-one-way flow clean area 14 as necessary are provided in the urethane shaft 64. Thereby, even if there is local exhaust exceeding the intake amount of the one-way flow clean area 12, the one-way flow clean area 12 does not become a negative pressure. Therefore, when the motor damper 56 is opened, excessive cool air does not flow into the one-way flow clean area 12.

In the second embodiment, the air is circulated by the circulating fan 66 in the one-way flow blower chamber 44. However, as shown in FIG. The fan filter unit 52 (FFU) in which one unit 54 is arranged or several HEPAs
A fan module unit (FMU) in which one fan unit is arranged for the filter may be used.

Further, the opening of the motor damper 56 may be controlled to adjust the mixing amount of air, or a vane may be used. Furthermore, when the heat load fluctuation in the one-way flow clean area is small, the mixing amount may be manually adjusted.

[0048]

According to the present invention, the air-conditioning temperature is reduced in a clean room in which a one-way flow clean area and a non-one-way flow clean area are provided side by side in order to process the heat load of the non-one-way flow clean area. be able to.
As a result, it is possible to reduce equipment costs and reduce air circulation power energy.

[Brief description of the drawings]

FIG. 1 is a front view of a clean room according to a first embodiment.

FIG. 2 is a front view of a clean room according to a modification of the first embodiment.

FIG. 3 is a front view of a clean room according to a modification of the first embodiment.

FIG. 4 is a front view of a clean room according to a second embodiment.

FIG. 5 is a front view of a clean room according to a modification of the second embodiment.

FIG. 6 is a front view of a clean room according to a modification of the second embodiment.

FIG. 7 is a front view of a conventional clean room.

FIG. 8 is a front view of a conventional clean room.

[Explanation of symbols]

 12 One-way flow clean area 14 Non-one-way flow clean area 20 Underfloor chamber (discharge chamber) 26 Ceiling plenum chamber (blowing chamber) 34 Hanging wall (compartment means) 36 Dry coil (air conditioning means) 38 Circulation fan (circulation means) 40 HEPA filter (cleaning means) 44 One-way flow blowing chamber 46 Push-in fan (blowing means) 48 Controller (air volume control means) 50 Temperature sensor 56 Motor damper (blowing means) 60 Partition wall (partition means) 62 Unidirectional flow discharge chamber 64 Retan Shaft 68 Check damper (exhaust port) 70 Check damper (inlet)

Claims (6)

[Claims] 1. A one-way flow clean area and a non-one-way flow clean area are provided side by side, and a blower chamber for sending air to a cleaning means provided at an outlet of each area, and air is discharged from a suction port of each area. A discharge chamber, an air conditioner that air-conditions air discharged to the discharge chamber to a predetermined temperature and humidity, and a circulation unit that circulates the air conditioned by the air conditioner to the blower chamber. Air-conditioning control means for lowering the temperature of the air to be air-conditioned by the air-conditioning means to a temperature at which the heat load of the non-one-way flow clean area can be processed; and dividing the one-way flow clean area and the non-one-way flow clean area A partitioning means, a one-way flow blowing chamber which is independently provided in the blowing chamber and sends air to a one-way flow clean area, and the one-way flow Clean room and having a blowing means for blowing air in the blowing chamber into the blast chamber, the. 2. A one-way flow discharge chamber independently provided in the discharge chamber, and a urethane shaft for circulating air from the one-way flow discharge chamber to the one-way flow blower chamber. The clean room according to claim 1, wherein 3. A temperature sensor provided in the one-way flow clean area, an air volume control unit for controlling an air volume of the air blowing unit based on a detection result of the temperature sensor,
The clean room according to claim 1 or 2, further comprising: 4. The clean room according to claim 1, wherein the partitioning means is a partition wall for making the one-way flow clean area airtight. 5. The clean room according to claim 4, wherein the partition wall is provided with an exhaust port for exhausting air in the one-way flow clean area and having a check function. 6. The clean room according to claim 4, wherein an inlet for taking in air from the non-one-way clean area is provided in the urethane shaft.