A clean room, also known as a clean room or a quiet room, is a room with air filtration, distribution, optimization, construction materials and devices, and is the basis for controlling pollution and cross pollution. Specific standard operating procedures are used to control the concentration of airborne particulates and airborne bacteria to achieve appropriate cleanliness levels. The main function of the clean room is to control the materials. The air in contact with the products includes temperature and humidity, so that the products have good production and storage space.
The development of clean room is closely linked with modern industry and cutting-edge technology. Due to the environmental requirements of precision machinery industry (such as gyroscope, micro bearing processing) and semiconductor industry (such as large-scale integrated circuit production), the development of clean room technology has been promoted. According to domestic statistics, the qualified rate of MOS circuit cores produced in the environment without the requirement of cleanliness level is only 10% – 15%, and that of 64 memory is only 2%. At present, clean rooms are widely used in precision machinery, semiconductor, aerospace, atomic energy, medicine and other industries. However, different industries have different requirements for the cleanliness of clean rooms.
1. Clean room requirements for semiconductor and integrated circuit production
The purification of semiconductor materials is an important basis for the development of semiconductor devices. Due to the process requirements of large-scale and ultra-large-scale integrated circuits, in order to obtain high-purity silicon materials, the high-purity of raw materials and intermediate media and the cleanliness of high-precision constant temperature and humidity production environment have become a prominent issue affecting product quality.
The yield of integrated circuit chips is related to the defect density of chips, while the defect density of chips is related to the number of particles in the air. Therefore, with the rapid development of integrated circuits, not only the size of controlled particles in the air is highly required, but also the particle beam needs to be further controlled; At the same time, there are also relevant requirements for chemical pollution control of dust-free workshop in the production environment of VLSI.
2. Clean room requirements for production of precision machinery and fine chemical products
With the development of science and technology, the production and processing of many industrial products put forward extremely high requirements for the dust concentration in the dust-free workshop in the production environment, which requires that the production environment have a certain air cleanliness level and control the supply quality of various related substances required for the production process. For example, in film production, if the film is polluted by dust, emulsion oxidation, activity reduction, PH change, etc. will occur, which will affect the film’s photosensitivity.
3. Clean room and dust-free workshop requirements for pharmaceutical product production
Drugs are special commodities used to prevent and treat diseases, recover and adjust body functions. Their quality is directly related to human health and safety. If some drugs are contaminated or cross-contaminated by microorganisms, dust particles, etc. during the manufacturing process, unexpected diseases and hazards may occur.
The grade standard of clean room is usually divided according to the only index of suspended particle concentration. The particle sensor is an instrument used to measure the quantity and particle size distribution of dust particles per unit volume in the clean room. It has the advantages of fast testing speed, dynamic distribution width, and no human influence. It is the main monitoring instrument used in production enterprises and scientific research departments such as paint spraying and environmental protection products.
In the precision machinery production workshop, the requirements for workshop cleanliness are very high. Particle sensor is an essential equipment in almost every precision electronic workshop. If there is such an instrument for monitoring particle concentration in our workshop, we can easily understand the dust situation in the workshop when we are in the office, and realize the intelligent experience of products.
For example, when we detect that the concentration of particulate matter in the workshop is too high, we can timely notify the relevant person in charge of the workshop and take necessary measures to reduce the concentration of particulate matter below the safety standard, which is very beneficial to the safe production of products and provide users with reliable and high-quality products. The UK alpha particle detector PM2.5 sensor dust sensor OPC-R2 is a small particle detector launched by alphasense after OPC-R1, which can detect PM1, PM2.5 and PM10. The equipment has higher flow rate and lower power consumption than OPC-N2 and OPC-N3. It is a product with high cost performance. British Alphasense PM2.5 sensor/atmospheric particle monitor OPC-N3 is an upgraded product of OPC-N2. Its appearance and size are the same as OPC-N2. Its range is 0.38-40um, and it can measure up to 2000 μ g／m3； The number of channels is expanded to 24, and the onboard temperature and humidity sensors are also provided; It can be applied to the monitoring of heavily polluted environment; In addition, Japan’s Figaro laser particle sensor PM2.5 sensor TF-LP01 is a small module that uses the scattering principle to detect dust particles in the air. It has the advantages of small size, high detection accuracy, good repeatability, good consistency, real-time response, continuous collection, strong anti-interference ability, ultra-quiet fan, 100% detection and calibration of the sensor after delivery, etc