Abstract
The study was to investigate the driving frequency effects on the characteristics of atmospheric plasma jets system. The discharge gas is the helium. We change the power source frequency range from 10 MHz to 20 MHz. As the driving frequency is increased, we can observe the several phenomena. (1) gas breakdown voltage from 256 V down to 204 V, (2) plasma density from 0.798×?10?^12 ?cm?^(-3) rose to 2.218×?10?^12 ?cm?^(-3) and increase the current from 0.125 A to 0.224 A when the plasma state at highest α mode discharge, (3) sheath thickness decreased from 0.348 mm to 0.257 mm before discharge mode transition, (4) the electron excitation temperature dropped from 0.535 ev 0.316 ev when the plasma power of 25 W. Collectively, these results suggest that the high driving frequency help to improve the quality of plasma, enhance discharge efficiency, and make the atmospheric plasma jets systems have a wider application space.