Features for Clean Rooms Air-conditioning
I.Temperature and humidity requirements are higher than general air-con.
The temperature requirement for general air-con is between 18°C and 26°C and the relative humidity is between 40% and 65%; while the temperature in Clean Room should be controlled between 22°C and 24°C and the humidity in it should be between 45% and 55%.
II.Constant temperature and humidity control
It is extremely temperature-sensitive for the semiconductor industry; therefore, the temperature and humidity should be controlled within ± 1°C and ± 3% in most of the Clean Room areas.
III.More air needed to balance the air pressure in Clean Room
A large amount of the chemicals and toxic gas will be required during the semiconductor production. Therefore, there will also be a huge amount of gas exhausted due to the volatile gas and exhaust gas. To maintain positive pressure inside the Clean Room, the air supply into the Clean Room is also relatively increased.
IV.Twenty-Four Seven running and monitoring on Air-con system
Part of the machines in the semiconductor production are highly sensitive to the temperature/humidity variation, such as the Stepper in Photo lithography area. A slight change of the temperature or humidity would affect the accuracy of the device. Moreover, the products like chips should be put in the environment with constant temperature and humidity. Therefore, the air-con system should be strictly monitored and managed.
V.Air pressure inside the Clean Room in the semiconductor factories
For the semiconductor factories, the air pressure in the Clean Room should be higher than the outside. Besides avoiding the influence from the temperature, humidity, and particles outside the Clean Room, it also helps extend the lifetime of the ULPA filter. However, the pressure difference should be constrained to avoid the cost increase from the increased out bounding air from Clean Room.
In order to remove the airborne particles inside the Clean Room, the air velocity shall reach the certain standard. Also, the airflow direction shall be controlled based on various levels of the Clean Rooms.