Study On The Fabrication And Properties Of Ultra-high Vacuum Channel Type Leak

Leak detection technology is widely used in aerospace, electronics, chemical, medical and other industries. With the development of space technology in recent years, seal requirement of equipment is also increasing. Existing standard ultra-high vacuum leak preparation technology is kind of limited, and it is difficult to control the size of the leak and calculate the leak rate. Based on the rarefied gas flow theory and micro-nano processing technology, this article proposed two new methods for the preparation of standard leak. Taking advantage of high precision and quantitative measurements of gas accumulation method, we designed and constructed standard leak calibrate system, and the standard leaks prepared were calibrated.This paper expounded the main background and significance of the research, analyzed the status of vacuum leak preparation domestic and overseas, put forward the contents of this paper and methods for this research.This paper introduced the concepts of vacuum and vacuum leak detection, discussed the state of the flow of gas and its discrimination.The calculation formula of gas flow and pipe conductance were deduced of rectangle and circular cross section respectively under molecular flow regime.This paper proposed two methods for the preparation of the channel-type standard leak. The one is a combination of UV curing and thermal nanoimprint lithography technology using polymer SU-8 and PDMS to prepare micron channel type standard leak. The other one uses uniform and known size two-way porous aluminum oxide (AAO) template, and obtains effective area to prepare the channel-type standard leaks.Taking the advantage of gas accumulation method to design leak detection system. We introduced major laboratory equipment, hardware devices, collection system of the detection system; analyzed the experimental steps, deduced calibrated leak formula. We tested the standard leaks with the system, analyzed experimental data with the theoretical value, concluded the causes of deviation, and proposed the experiment improvement program.