There is a certain residual gas in the high vacuum environment where the oil diffusion pump is used, more than 80% of which are water vapor, oil vapor and other high boiling point steam, but the ability to remove residual gas is low, the time is long, and all residual gas is The gas is also a source of contamination of the workpiece, which affects the yield and quality of the product. The ultra-low temperature direct cooler is the best choice to solve this kind of problem.

The working principle of the direct-cooling ultra-low temperature refrigerator: a refrigeration coil that can reach below -120°C is placed in the vacuum chamber or the pump port of the oil diffusion pump, and the vacuum system is quickly captured by the low-temperature condensation effect on its surface. of residual gas. Thus, the vacuuming time is greatly shortened (60-90% of the vacuuming time can be shortened), and a clean vacuum environment is obtained.