The characteristics of indium tin oxide films prepared on various buffer layer-coated polymer substrates

The optoelectronic and mechanical properties of flexible indium tin oxide (ITO) films are critical to the development of flexible optoelectronic devices. To improve the characteristics of the flexible films, the effects of inorganic buffer layers on the optoelectronic and mechanical characteristics of flexible ITO films prepared by ion-beam assisted deposition at room temperature were investigated. The results show that four inorganic buffer materials: SiO2, Ta2O5, Al2O3 and TiO2, have different effects on the optical transmission, sheet resistance and mechanical properties of ITO films. Ta2O5 buffer layer induces the highest optical transmission. SiO2 buffer layer leads to the lowest sheet resistance. TiO2 buffer layer reveals the most superior electrical stability against bending, which is attributed to the low thermal stress in ITO film.