Effect of Annealing with Ar Plasma Irradiation for Transparent Conductive Nb-Doped TiO₂Films on Glass Substrate

Abstract

Conductive Nb-doped TiO 2 films (TiO 2 :Nb) on glass substrates formed via post annealing of as-deposited amorphous films are expected to be an alternative next-generation transparent conductive oxide (TCO). We investigated the effects of annealing with Ar plasma irradiation on TiO 2 :Nb films that had been grown on glass substrates by reactive sputtering. It was revealed that annealing at 300 C with Ar plasma, in which the plasma density was as high as 6 Â 10 11 cm À3 , induced a rapid decrease in resistivity to the order of 10 À3 cm within several minutes. Plasma-irradiation-induced oxygen defects were suggested to be responsible for the rapid decrease in resistivity rather than the activation of incorporated Nb atoms through crystallization. The film annealed with the high-density plasma for 20 min showed optical transmittance of approximately 80% for the visible wavelength region with a minimum resistivity of 1:5 Â 10 À3 cm, demonstraiting the advantages of the proposed method for fabricating TiO 2 :Nb films as TCOs. #

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