Secondary electron emission suppression on alumina surface and its application in multipactor suppression

For the high-power microwave (HPM) components applied to space environment, seed electrons in may resonate with radio-frequency electrical field and further lead secondary electron multiplication occur, triggering off phenomenon of multipactor. Multipactor deteriorates performance components, severe circumstances, it is even possible result failure or spacecraft. Alumina ceramic possesses good dielectricity, high hardness, thermal isolation, low dielectric loss, etc., so widely used HPM systems including windows, many other components. However, alumina a relatively level yield (SEY <i>δ</i>), indicating that devastating effect multipactor discharge likely be triggered inside alumina-filled environment. In this work, model loaded coaxil pass fillter simulated verify reducing SEY surface effective necessary improve threshold. After that, we use several technologies achieve an ultralow on surface. Firstly, series microstructures different porosities aspect ratios fabricated. The results indicate microstructure 67.24% porosity 1.57 ratio shows excellent low-SEY property, which able suppress peak value (<i>δ</i><sub>m</sub>) from 2.46 1.10. Then, various process parameters are fabricate TiN films silicon sheets. Experimental film achieves lowest <i>δ</i><sub>m</sub> 1.19 when gas flow N<sub>2</sub>∶Ar 7.5∶15. Thereafter, deposit coating onto laser-etched samples, 0.79 finally achieved Then implement qualitative analysis explore influence charge emission for microstructured surface, discuss mechanism surfaces mitigating unilateral bilateral verifying actual suppression multipactor, constructing depositing filled designed coaxial filter. Finally, obtain significant improvement threshold filter, increases 125 W 650 W, 7.16 dB. This work develops method reduce alumina, great scientific significance revealing dielectric-filled also engineering application improving reliability