ITO and IZTO films were deposited as a function of the substrate temperature using a sintered ceramic target by pulsed DC magnetron sputtering. The influence of the substrate temperature on the microstructure, surface morphology, electrical, and optical properties was investigated. The amorphous IZTO films deposited at low substrate temperature showed very smooth roughness (< ~ 0.5 nm) with very fine grains, while polycrystalline ITO films exhibited rough surface (> ~ 8.0 nm). With increasing substrate temperature, the transparent conducting properties of ITO films were improved. However, opposite tendency occurred for IZTO thin films. The amorphous IZTO film deposited at room temperature showed high transmittance of 89.3% and low resistivity of 5.6 × 10-4Ω • cm. In addition, the measured work function of IZTO films had relatively higher value (> 5.0 eV) than that of ITO films (< 4.9 eV) regardless of substrate temperature. In conclusion, IZTO thin film can be used as an alternative material for ITO film as an electrode of flexible flat panel displays.

Keywords: TCO (Transparent conducting oxide), ITO (Indium tin oxide), IZTO (Indium zinc tin oxide)