Space and time resolved optical emission spectroscopy characterization of inductively coupled RF water vapour plasma

Inductively coupled RF water vapour plasma generated in a linear glass tube was studied by means of optical emission spectroscopy. Low pressure water vapour plasma was created by an 8 turn coil with an EM field oscillating at 13.56 MHz. Various total pressures (5–14 Pa) and discharge powers (100–300 W) were investigated. Excitation temperatures (between 0.6 and 1.0 eV) of the plasma discharge were determined from emission spectra by employing the Boltzmann plot method. E- and H-modes of plasma and transitions among them were observed. Hysteresis effects were observed by the change in water vapour pressure and discharge power through monitoring of O, H and OH spectral features.