On the physical properties of In2O3 films prepared by atomic layer deposition using tri-methyl-indium and nitrous oxide

Indium oxide (In₂O₃) films were directly grown on (0001)-plane sapphire substrates by atomic layer deposition (ALD) using tri-methyl-indium (TMIn) and nitrous oxide (N₂O). The structural, optical and transport properties of the In₂O₃ films were characterized by ¿-to-2¿ x-ray diffractometry (XRD), field emission scanning electron microscopy (FESEM), Hall measurements, and transmission spectroscopy. Based on the XRD results, In₂O₃ films were found to show <111> preferred orientation. As-grown In₂O₃ films are n-type in nature with typical room temperature (RT) electron concentrations and mobilities being in low 10¹⁸ cm^-3 and 10~20 cm²/V-sec, and the optical transmittances and resistivities of the In₂O₃ films are typically ~80% and low 10^-1 ¿-cm, respectively.