The characteristics in low-pressure inductively coupled CF4 plasma have been-inv estigated using a Langmuir probe method. Results for the CF4 gas have shown that there are two electron populations: one with low temperature and high densit y and the second w ith higher temperature and lower density, in this region. Fast electron temperat ure The, slow electron temperature Tceand mean electron tem perature Te decrease , while their densities nhe,nce, ne increase with in creasing r.f. input pow er. Our findings suggest that the dependence of two-electron-temperature on r. f.input power can be explained by the thermodynamic equilibrium of the collision between electrons and particles.