Effect of tin concentrations on properties of indium tin oxide films deposited on PET substrate under various conditions

This study examined the effect of the Sn concentration on the electrical and mechanical properties of ITO films. ITO films, 150–160 nm in thickness, were deposited on polyethylene terephthalate (PET) substrates by DC magnetron sputtering under various deposition conditions using one of three different high density ITO targets (10 wt%, 7 wt% and 5 wt% SnO2) without substrate heating. Deposition was carried out under the following conditions: DC power; total gas pressure; distance between target and substrate; and O2 or H2 addition ratio. The lowest resistivity of 3.19 × 10−4 Ω cm and relatively small change in resistance in dynamic stress mode was obtained for the film deposited from an ITO target doped with 7wt% SnO2. These results can be explained by the effect of the kinetic energy of sputtered atoms (In, Sn, O) and the bombardment of high energy particles (Ar0, O−) arriving at the film surface during deposition.