The vacuum coating equipment is composed of many precise parts, which are made through many processes, such as welding, grinding, turning, planing, boring, milling and so on. Because of these works, the surface of equipment parts will inevitably be contaminated with some pollutants such as grease, oil dirt, metal chips, welding flux, polishing paste, sweat marks and so on. These pollutants are easy to volatilize under vacuum conditions, thus affecting the ultimate vacuum of the equipment.
In addition, these vacuum pollutants from mechanical processing absorb a large amount of gas in the atmospheric pressure environment, and in the vacuum state, these previously adsorbed gases will also be released again, becoming a major factor limiting the limit vacuum. For this reason, the pollutants must be removed before the parts of the vacuum coating machine are assembled.
During the use of vacuum equipment, its components will also be contaminated. However, the pollution from this source is mainly caused by the use conditions and vacuum pump.
1. The evaporation of the filament of the vacuum gauge under high temperature conditions will lead to the formation of a film on the ceramic insulator, which will damage its insulation strength to a certain extent, and also have a certain impact on the accuracy of its measurement;
2. Due to high temperature evaporation, a metal film will be formed on the surface near the filament of the electron gun in vacuum;
3. Due to workpiece sputtering, the inner wall of ion beam etching equipment will be contaminated by splashes;
4. The inner wall of the vacuum evaporation coating equipment will be contaminated by its evaporation target material;
5. Vacuum drying system is often used, and the system will be contaminated by the evaporated substances;
6. The diffusion pump oil and mechanical pump oil in the vacuum coating equipment are also a major source of pollution. After the coating machine has been working for a long time, an oil film may form inside the equipment.
To sum up, the vacuum sanitation of equipment involves vacuum equipment, vacuum system, vacuum process production and other aspects and links, as well as the requirements of the vacuum coating equipment itself and special vacuum process on the use conditions. Therefore, vacuum pollution is a problem worthy of attention, because these pollution will affect the performance of the equipment, and attention should be paid to regular or at any time cleaning.
Post time: Feb-21-2023