Factors Influencing Ultrahigh Vacuum in Microwave Electron Devices

摘要

In microwave electronic device design, the residual gases problem is usually given secondary attention though its effects on device performance and reliability can be of primary importance. The initial effects of residual gases in complex microwave electronic devices can adversely affect the cathode emission, beam focusing, output power, noise level, and internal vacuum almost instantaneously. In addition, irreparable damage can be done to internal precision components which can result in the premature failure of the device. Recent advances in the state-of-the-art in partial pressure mass spectrometer systems make a residual gases analysis of the materials and methods of microwave device fabrication possible on a rapid and scientifically accurate basis. To attain and to maintain the ultra-high vacuum needed for optimum performance, long life, and high reliability demanded by modern technology of microwave electronic devices, a knowledge of the interactions of gases with solid surfaces is required. The problem of residual gases in microwave electronic devices is discussed with respect to adsorption and desorption and the composition, sources and types of residual gases. (Author)