Effect of Oxygen Flow Rate on the Optical, Electrical, and Mechanical Properties of DC Sputtering ITO Thin Films

Abstract

This study presents the effect of oxygen flow rate on the optical, electrical, and mechanical properties of indium tin oxide (ITO) thin films prepared by the DC magnetron sputtering technique. The oxygen flow rate was varied from 10 to 50 sccm. The ITO thin films deposition under different oxygen flow rates exhibits different properties. We used an optical spectrometer to measure the optical transmittance and a four-point probe instrument to determine the resistivity. A home-made Twyman-Green interferometer was used to evaluate residual stress and a microscopic interferometer was used to measure the surface roughness of ITO thin films. The experimental results show that the average optical transmittance is larger than 85% in visible range; the electrical resistivity has a minimum 6.85 × 10 −4 ohm-cm for the oxygen flow of 10 sccm. The residual stress is varied from −0.15 GPa to −0.34 GPa in the range of 10-50 sccm. The root-mean-square (rms) surface roughness is changed from 2.64 nm to 2.74 nm as the oxygen flow rate increases. The results show that the oxygen flow rate has significant influence on the electrical resistivity, residual stress, and surface roughness of the ITO thin film.

Application-Specific Oxide-Based and Metal–Dielectric Thin-Film Materials Prepared by Radio Frequency Magnetron Sputtering

“…Sputter deposition process parameters, such as total or partial gas pressure(s), process gas chemistry, substrate type, substrate-stage heating temperature, substrate-stage rotation rate, substrate-to-target distance, target rotation rate, and RF powder densities, are well known to affect the growth and properties of thin-film materials. There are many reports published in the literature describing the necessity of sputter deposition process parameter optimization for many application-specific oxide-based and other thin-film materials [81,82,83,84,85,86,87,88,89,90,91]. For example, sputter deposition process parameters were studied and optimized to deposit ruthenium oxide (RuO 2 ) thin films with strong adhesion properties for manufacturing durable sensing electrodes [87,91].…”

Influence of Al impurities on the electrical properties of ZnO films

“…Из Табл. 2 следует, что пленки ZnO с концентрацией примеси Al (1÷ 2) ат.% характеризуются величиной удельного сопротивления ρ = (4 ÷14) ·10 −3 Ом · см, что сопоставимо с удельным сопротивлением пленок ITO (In 2 O 3 +10 % SnO 2 ), содержащих дорогостоящих индий [19] и применяемых в качестве прозрачных электропроводящих покрытий.…”

Optical and electrical properties of Ti-doped In2O3 film deposited on flexible transparent substrates by ion beam assisted deposition under different oxygen flow rate

“…Oxygen vacancies can increase the double charge of oxygen. The existence of TiO 2 will result in  doping of the lattice due to the doped materials that would be increased electrons to the conduction band [25][26][27] .…”