Influence of the grain boundary barrier height on the electrical properties of Gallium doped ZnO thin films

► GZO thin films were deposited by PLD with the various Ga doping. ► The carrier concentration and oxygen vacancies in the GZO thin films increased with an increase of Ga doping. ► The 3.0% Ga doped thin film exhibited the lowest resistivity as low as 3.63 × 10−4 Ω cm. ► The lower barrier height of grain boundaries would cause the lower resistivity.