UC Irvine

Velocity distribution functions of metastable argon ions (3 d′ 4 F72) have been measured to obtain metastable ion density and temperature by the diode laser-induced fluorescence (LIF) technique in magnetized inductively coupled plasma as a function of pressure, rf power, and magnetic field strength. Calculated density from a rate equation agrees with the trends observed in the experimental data. From the calculation, the metastable ion density should be over 107 cm-3 to obtain a LIF signal. From a dc bias experiment, it is suggested that the spatial potential can be the dominant ion heating source, and a simple global model for ion temperature is constructed. In this model, approximately 0.01% and 10% of total spatial potential energy can contribute to ion and neutral temperatures, respectively. The measured ion temperature agrees with the calculation. © 2006 American Institute of Physics.