Effect of Surface Charge on Ignition of RF Impulse Discharge Used for Surface MgO Coating in A Small-Diameter Glass Tube

摘要

A method for performing inner wall surface processing has been investigated by generating microplasmarnunder sub-atmospheric pressure in a narrow glass tube. Micro-discharge takes place in arnnarrow tube by RF impulse power supply, using a small coaxial electrode. Effects of surface chargesrnon the ignition of discharge are investigated under different conditions of surface impedance. Wernfind that repetition frequency of the impulse affects the breakdown voltage seriously. When thernrepetition frequency is increased, the surface charges accumulated on the inner surface of the tube arernremained. This causes a decrease in the breakdown voltage. In case of higher repetition frequency,rnwe also demonstrate depositions of MgO microparticles on the inner wall of the glass tube. We findrnthat high quality MgO microparticles are deposited.