Total Energy Efficiency Excitation, Relaxation, and Chemical Factors

Components of Total Energy Efficiency Excitation, Relaxation, and Chemical Factors 

The total energy efficiency of ary non-equilibrium plasma-chemical process can be subdivided into three main components an excitation factor (jjex), a relaxation factor (jjrei), and a chemical factor ( chem)  

The relaxation factor (jjrei) is related to conservation of the principal active species (like F atoms or vibrationally excited molectrles in the preceding examples) with respect to their losses in relaxation, recombinatiorr, and so on. In processes stimulated by vibrational excitation, the factor r] ei shows the fraction of vibrational energy that can avoid vibrational relaxation and thus be spent in the chemical reaction of interest. VT relaxation is slow inside of a discharge zone if TV TV therefore, near the E threshold. 

The preceding relation indicates the threshold of dependence, r](Ey), and shows that when the vibrational temperature finally becomes lower than the critical value, most of the vibrational energy goes to VT relaxation. 

The chemical factor ( chem) shows the efficiency of the principal active discharge species in the chemical reaction of interest. In the process of NF3 dissociation and F-atom generation for CVD chamber cleaning, the chemical factor ( chem) shows the efficiency of the atoms in the gasification of impurities. In plasma-chemical reactions stimulated by vibrational excitation, chem can be presented as 

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