The effects of inorganic buffer layers on the flexible indium-tin-oxide films' photoelectric properties and bending resistance performance

Inorganic buffer layers and transparent conductive In₂O₃:SnO₂ (ITO) films were deposited sequentially on flexible polyethylene terephthalate (PET) substrates by ion assisted deposition(IAD) at room temperature. The effects of inorganic buffer layers on the photoelectric properties and bending resistance performance of flexible ITO films were investigated detailedly. The results show that the effects of SiO₂, TiO₂, Ta₂O₅ and Al₂O₃ buffer layers on the sheet resistance, optical transmittance and bending resistance performance of ITO films are different. Adding SiO₂ to reduce the sheet resistance of ITO films is the best proposal, of which the reducing rate reaches 29.8%, but adding Al₂O₃ is inadvisable, of which the reducing rate is only 5.6%; The visible light transmittance of ITO films with Ta₂O₅ is optimal, of which the average transmittance is over 85%, and the average transmittance of ITO films with SiO₂ is above 80%. It is found that the ITO films with SiO₂ have better resistance stabilities compared to ones with TiO₂ when the ITO films are bent at the same bending radius, but the ITO films with SiO₂ have worse resistance stabilities compared to ones with TiO₂ when the ITO films are inwards bent at the bending radius of R=0.8 cm and R=1.2 cm.