Effect of surface charge trapping in dielectric barrier discharge

Summary form only given. The experiment of dielectric barrier discharge in a 2-mm air gap shows that the pressure range of a uniform discharge using polytetrafluoroethylene as barrier is much wider than that using quartz or alumina. The parameters of the charge trapped on the surface of these three dielectric barriers were obtained by surface charge measurement and thermally stimulated current measurement. It was found that surface charge trapping has much influence on the uniform discharge, i.e., the seed electrons necessary for uniform discharge may be produced by the desorption of the absorbed electrons in the shallow trap with energy level lower than 1 eV. Results from scanning electron microscopy, Fourier transform infrared spectroscopy and the measurement of thermally stimulated current show that a high density of the physical defects and the chemical defects are introduced into the surface of the silicone rubber plates after they are treated by corona discharge plasma. These defects behave electrically as shallow electron traps, leading to the formation of a uniform discharge in air at higher pressure when the corona-modified silicone rubber is used in dielectric barrier discharge.