Modeling of Mass and Energy Transport in H2 Plasma Obtained under Diamond Deposition Discharge Conditions

We present here a one-dimensional dimisional model which describes the species and energy transport in H 2 plasma obtained under moderate pressure discharge conditions. In this model, the H 2 plasma is considered as a three temperature thermochemically non-equilibrium flow with three different temperatures, T g , T v and T e , and seven species undergoing 27 chemical reactions. The equations which govern the temperatures and the species densities were solved for several diamond deposition discharge conditions (power and pressure). The comparison with experimental measurements shows that the gas and H 2 vibration temperatures are well predicted by the model while a discrepancy was obtained for H-atom mole fraction. Results show that most of the microwave power absorbed by the electron is dissipated in the activation of H 2 molecules dissociation (58%) and energy transfer to heavy species translation-rotation and H 2 -vibration modes (40%). They also show that the increase of the average microwave power density (MWP av ), in the range [9 W/cm 3 , 30 w/cm 3 ] leads to the increase of the gas temperature and H-atom mole fraction and to the decrease of the electron temperature and ionization degree.