Uniformity of radio frequency dielectric barrier glow discharge in atmospheric helium plasma

The spatio-temporal characteristics of radio frequency dielectric barrier glow discharge at atmospheric pressure (RF-DBGDAP) was investigated by using the lab-built transparent reactor, consisting of the water-cooled copper electrode (100 mm×100 mm) covered by fused-silica and the water electrode grounded via a copper-sheet ring. The radial distributions and the axial distributions of glow discharge intensity and their time-evolutions were analyzed by utilizing inten sified charge coupled device (ICCD) camera. The results show that the radial dis tributions and the axial distributions of glow discharge intensity were not only highly uniform but also periodically varied with radio frequency. It's deduced that the space charges play a dominant role in uniformity and evolution of RF-DBGDAP. In contrast to medium frequency dielectric barrier glow discharge at atm ospheric pressure (MF-DBGDAP), the non-uniformity in radial direction wasn't observed. It is believed that RF-DBGDAP will be much suitable for uniform thin film deposition and polymer surface modification. ©, 2015, Zhenkong Kexue yu Jishu Xuebao/Journal of Vacuum Science and Technology. All right reserved.