Atmospheric pressure glow discharge plasma process

Atmospheric pressure plasma processes applicable to solar cell processes are therefore dry etching, surface cleaning, etching, and activation. Layer reductions using hydrogen-based atmospheric glow discharge plasmas are also employable. 

The fact that glow discharges have much lower atom number densities than atmospheric pressure plasmas is responsible for the fact that the measurement of fundamental parameters such as electron number densities, electron temperatures, etc. by techniques such as Thomson scattering is much more difficult than in the case of atmospheric pressure plasma discharges, and that this is only now becoming a field of active research. Moreover, the lower collision frequency, which causes large departures from local thermal equilibrium, is responsible for the fact that many more processes are significantly involved in the excitation mechanisms than in the case of atmospheric pressure plasmas. 

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