The effects of dielectric layer and a driving method on the discharge characteristics of atmospheric-pressure micro plasmas

Atmospheric pressure plasmas which do not need a vacuum chamber have attracted great attentions for various applications such as surface modification and bio medical equipment. A one-dimensional particle-in-cell Monte Carlo collision (PIC-MCC) simulation is adopted to understand the characteristics of a parallel-plate micro plasma with a driving frequency varying from 13.56 MHz to 100 MHz and with a gap distance less than 100 micrometers. The difference between a dielectric barrier discharge and a dielectric-free discharge is investigated by comparing the spatiotemporal evolution of plasma density and excitation collisions as well as the electron energy distribution function (EEDF). Also, investigated are the effects of driving method such as sinusoidal RF and pulsed-DC on the EEDF and excitation collisions. With the choice of driving method combined the choice of whether dielectric barriers exist or not, it is possible to select a preferable EEDF of a micro atmospheric pressure plasma.