Crystallinity, etchability, electrical and mechanical properties of Ga doped amorphous indium tin oxide thin films deposited by direct current magnetron sputtering

Abstract

Indium tin oxide (ITO) and Ga-doped ITO (ITO:Ga) films were deposited on glass and polyimide (PI) substrates by direct current (DC) magnetron sputtering using different ITO:Ga targets (doped-Ga: 0, 0.1 and 2.9wt.%). The films were deposited with a thickness of 50nm and then post-annealed at various temperatures (room temperature-250°C) in a vacuum chamber for 30min. The amorphous ITO:Ga (0.1wt.%Ga) films post-annealed at 220°C exhibited relatively low resistivity (4.622x10−4 Ωcm), indicating that the crystallinity of the ITO:Ga films decreased with increasing Ga content. In addition, the amorphous ITO:Ga films showed a better surface morphology, etchability and mechanical properties than the ITO films.