Physical properties of flash evaporated In2O3 films prepared at different substrate temperatures

Indium oxide (In2O3) thin films were prepared by flash evaporated technique under various substrate temperatures in the range of 303–673 K and systematically studied the structural, electrical and optical properties of the deposited films. The films formed at substrate temperatures of < 373 K were amorphous while those deposited at higher substrate temperatures (≥ 373 K) were polycrystalline in nature. The optical band gap of the films decreased from 3.71 eV to 2.86 eV with the increase of substrate temperature from 303 K to 673 K. Figure of merit of the films increased from 2.8 × 103 Ω− 1 cm− 1 to 4.2 × 103 Ω− 1 cm− 1 with increasing substrate temperature from 303 K to 573 K, thereafter decreased to 2.2 × 103 Ω− 1 cm− 1 at higher temperature of 673 K.