Conduction mechanism of highly conductive and transparent zinc oxide thin films prepared by magnetron sputtering

Abstract This report describes the results of experimental and theoretical studies of the electrical properties of highly conductive and transparent ZnO thin films prepared by magnetron sputtering. The mobilities of undoped and Al-doped ZnO (AZO) films (carrier concentration 10 20 -10 21 cm -3 ), which are relatively independent of the crystal quality, are mainly dominated by ionized impurity scattering. The relationship between the carrier concentration and the mobility of AZO films can be interpreted by the Brooks-Herring theory when both the degeneracy and nonparabolicity of the conduction band are taken into account. The origin of carriers in AZO films is also discussed.

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