Time-dependent global model for electronegative high-density plasma discharges

Summary form only given, as follows. We develop a global model of high-density plasma discharges in molecular gases. The global model consists of the energy and particle balance equations for neutral and ionic species. The energy balance equation includes energy-loss for electron-neutral collisions, and electronic excitation, dissociation, ionization, dissociative attachment, and recombination. Particle balance equations are written for all species of interest. For a specified discharges length and diameter, absorbed power, pressure, reaction rate coefficients and surface recombination constants, we solve these equations to determine all species densities and the election temperature. High-density discharges such as inductively coupled plasma sources typically operate at low pressure of 1-20 mTorr and high input powers of 1-3 kW. Pulsed-time modulation of the input power has been used to improve processing rates and etch selectivity in high-density discharges. We investigate plasma characteristics of a pulse-time modulated high-density discharge using volume averaged global model. Also, we calculate the fractional dissociation and the ratio of the negative ion density to the electron density as a function of the wall recombination constant.