Transparent-conducting thin films of zinc oxide were prepared by vacuum evaporation and spray-pyrolysis techniques. A simple set-up for production of atomic-hydrogen plasma was designed and made. ZnO samples were hydrogenated at different substrate temperatures and for different hydrogenation times. Hydrogenation at a substrate temperature of 250 C for 45 min considerably increased the electrical conductivity of ZnO films approx. by 340% . Hall measurements showed that the hydrogenation process did not change carrier concentration in the films greatly. Thus the increase in the conductivity can be essentially attributed to a considerable increase in carrier drift mobility. This in turn, is attributed to deactivation of ‘dangling bonds’ associated with the structural defects in ZnO films by hydrogen ions. It was also found that the hydrogenation process did not noticeably affect optical transparencies and microstructure of the films.

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