Electrical and Optical Studies of Reactively Sputtered Indium Oxide Thin Films
Sreeram Sundaresh, Shraddha Dhanraj Nehate, Kalpathy B. Sundaram
Abstract
Electrical and optical properties of transparent conducting Indium Oxide (In 2 O 3 ) thin films were studied. These films were deposited by reactive RF sputtering process using Indium target in the presence of oxygen as reactive gas with argon. The pressure and the oxygen gas flow ratios during sputtering were varied to investigate their effect on the resistivity, optical transmission, refractive index, and optical bandgap of In 2 O 3 thin films. The lowest reported resistivity in this study is 2 × 10 −3 Ω-cm. The optical transmission was more than 80% in the wavelength range of 400 nm to 800 nm. The optical study revealed the wide optical bandgap of 3.712 eV and 3.875 eV of the deposited In 2 O 3 films. The films showed refractive indices in the range of 1.99 to 2.22. The elemental composition of In 2 O 3 films has been studied through X-ray Photoelectron Spectroscopy (XPS).