Time-dependent global modeling of pulse-power-modulated low pressure oxygen plasmas

A time-dependent global model, which consists of energy and particle balanc e equations, is formulated for a pulse-power-modulated low pressure oxygen discharge plasma. The time evolution of the electron temperature and the pl asma density are calculated. Also, the time-resolved charged-particle densi ty and flux are obtained by changing the duty ratio, the modulation frequen cy, the pressure, and the input power. The effects of pressure and power ar e checked with the scaling relations derived based on a global balance. The peak negative-ion density in the afterglow increases with the modulation f requency and the input power, decreases with the duty ratio, and shows a ma ximum with pressure.