Plasma parameters analysis of various mixed gas inductively coupled plasmas

The electron energy distribution functions and plasma parameters in various gas mixture discharges (N-2,O-2,CF4/He,Ar,Xe) are measured. When He is mixed, the electron temperature increases but the electron density is almost constant. The electron temperature increases rapidly near a He mixing ratio of 1, but it is almost constant when the mixing ratio is small. In Ar mixture discharge, the electron temperature is almost constant; the electron density increases rapidly near a mixing ratio of 1, but increases slightly when the mixing ratio is small. Mixing Xe increases the electron density and decreases the electron temperature. The electron density varies in a similar way with that of the Ar mixing case. A simple two-ion-species global model is used to analyze the plasma parameter variations as a function of mixing ratio, and it agrees well with the experimental results. (C) 2002 American Institute of Physics.