Catalytic Processes in Deposition and Etching of Solids

As in the previous sections, some of the processes to be discussed here do not obey the classical definition of catalysis. Nevertheless, they have a similar effect in promoting reactions which would, otherwise, not proceed at the given temperature because of a high kinetic barrier for thermal activation. In fact, some of the reactions would be even impossible to proceed thermally because of instability of the products at the high temperatures necessary for the thermal activation. 

Electrons, ions, atoms, radicals and excited species are typically those promoting such reactions. In intense glow discharges, their concentrations reach significant values changing the overall reaction stoichiometry and, consequently, the steady-state concentrations of reactants and products. Thus, purely catalytic effects of the plasmas are observed only in weak discharges 

The catalytic effects to be discussed include the processes taking place in the gas phase and on the surface of the solid. The former have the effect of promoting the 

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