Conductivity of ITO film amplified by multi-step ion beam-treatment on PET layers at room temperature

In this paper, we investigate poly‐crystal indium tin oxide (ITO) film produced by a multi‐step ion beam treatment on polyethylene terephthalate (PET) at room temperature. In the process of ITO film deposition by a sputtering method, we perform an ion beam treatment after some quantity of ITO deposition is complete, and this process is carried out repeatedly until the required film thickness is achieved. X‐ray diffraction indicates that the ITO film deposited by our multi‐step ion beam treatment has an almost poly‐crystal structure with a morsel of amorphous structure in the PET layers. As a supplementary measurement, a contact angle method shows that the poly‐crystal structure is due to a surface charge effect. Consequently, the electrical conductivity of the ITO film (resistivity measurement error bar