Secondary Electron Emission Measurements on Materials Under Stress
Abstract
The breakdown of rf windows used in high-power klystron is one of the most serious problems in the development of klystrons. The dielectric breakdown strength of an alumina ceramic surface depends on the secondary electron emission which is influenced by the electronics states of the oxygen vacancy existing adjacent to the ceramic surface. In this report, the durability of several dielectric materials used for rf windows is discussed in terms of secondary of electron emission (SEE), cathode luminescence, and dielectric loss. High-power tests of these materials with TiN coating, thus having low SEE, were also carried out using a traveling wave resonant ring. The samples were compared under the conditions of annealing and X-ray irradiation. The influences of annealing and X-ray irradiation on the SEE coefficients and CL spectra were investigated. Energy distributions of secondary electrons under high temperature were analyzed as well. The results show that alumina ceramics are superior to sapphire and aluminum nitride. The original of breakdown was investigated and the requirement for rf window materials presented.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 2004
- Accession Number
- ADA440247
Entities
People
- Shinichi Kobayashi
- Yoshio Saito
Organizations
- Saitama University