Optical and Electrical Properties of Indium Molybdenum Oxide Thin Films by the Co-Sputtering Method

Abstract

We studied the electrical and optical properties of indium molybdenum oxide (IMO) as transparent conducting oxides. IMO thin films were deposited by co-sputtering of In2O3 and Mo targets under control of the target power and substrate temperature. With an increasing Mo-doping level upto 1.34 at.%, the resistivity of the IMO thin films gradually increased from 1.18 x 10(-3) Omega cm to 4.89 x 10(-3) Omega cm, while their mobility decreased from 11.35 cm(2)V(-1)s(-1) to 2.8 cm(2)V(-1)s(-1). However, there was little dependence of the deposition temperature on the resistivity. The optical transmittance of IMO thin films grown at 100 degrees C was about 92.8% under wavelength ranges from 300 to 800 nm, and the band gap of all the films showed nearly 3.6 eV. The work function of the IMO thin films decreased slowly from 4.35 eV to 4.25 eV with increasing Mo-doping levels. These results may aid in the fabrication of a proper structure for optical devices using IMO thin films.