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How to control the temperature and humidity in a dust-free clean room

Industrial modular Clean Room time:2021/01/18 09:30:15 click:609

The temperature and humidity of the clean space is mainly determined according to the process requirements, but under the condition of meeting the process requirements, the sense of comfort of people should be taken into account. With the improvement of air cleanliness requirements, there is a trend that the requirements of temperature and humidity are more and more stringent. The specific process of the temperature requirements will be listed later, but as a general principle, because the processing accuracy is more and more fine, so the temperature fluctuation range requirements are getting smaller and smaller. For example, in the lithography and exposure process of large scale integrated circuit production, the thermal expansion coefficient difference between glass and silicon wafer as the mask material is required to be smaller and smaller. The silicon wafers with a diameter of 100 um, temperature rise of 1 degree, raises 0.24 um linear expansion, so must have a plus or minus 0.1 degrees of constant temperature, humidity also required value generally lower, because the person is sweating, the product will have the pollution, especially afraid of sodium semiconductor workshop, the workshop temperature should not be more than 25 degrees, the problem of high humidity is more. When the relative humidity exceeds 55%, the cooling water pipe wall will be dewy. If it happens in the precision device or circuit, it will cause a variety of accidents. It is easy to rust when the relative humidity is 50%. In addition, when the humidity is too high, it will be difficult to remove the dust chemically adsorbed on the surface of the silicon wafer by water molecules in the air. The higher the relative humidity is, the more difficult it is to remove the adhesion. However, when the relative humidity is lower than 30%, the particles are easy to adsorb on the surface due to the effect of electrostatic force, and a large number of semiconductor devices are prone to breakdown. The best humidity range for silicon wafer production is 35-45%.

How to control the temperature and humidity in a dust-free clean room

What exactly is a clean room?

At present, the development of precision parts and parts of the photoelectric industry is inseparable from the clean room. The role of the clean room is as small as the manufacturing of diodes and three-level tubes, and as large as the manufacturing of mechanical parts of national defense industrial aircraft and tanks.

First, the role of clean room:

Will be within the scope of a certain space (air) in the tiny particles of dust, bacteria and other harmful air pollutants, and the indoor temperature and humidity, cleanliness, interior pressure, air distribution and speed, noise, vibration and static lighting control within the scope of a certain demand, can make the products in a good environment of production, manufacturing, and specially designed rooms called dust-free clean room.

II. Grade of clean room:

Clean rooms are classified according to the cleanliness of the space. Class 1 means that no more than 1 dust particle (≥ 0.5mm (10-6m)) per cubic foot of indoor air is contained. Cleanliness of Class 10 is no more than 10. And so on.

Three, clean room category:

1. According to the industry, clean room is divided into medical industry, industrial manufacturing industry, known as negative pressure type clean room and positive pressure type clean room;

2 clean room according to the pattern, divided into layer flow, turbulent flow clean room.