Laminated Transparent Conducting Thin Films Prepared by Pulsed Laser Deposition.

Abstract

There are many unsettled questions for transparent conducting ITO thin films if used as electronic devices : expensive and weak in durability to reduction gas. In order to improve these disadvantageous points, AZO (ZnO : Al2O3) was deposited on the ITO layer by PLD method and laminated transparent conducting films with a structure of ITO + AZO were prepared. It was found that if the film thickness of the upper AZO layer increased, the sheet resistance decreased. At the same time, the increase of averaged transmittance in the visible wavelength region (400700 nm) due to an anti-reflection effect caused by two layer structure of ITO +AZO was recognized. Moreover, it was found from SEM and AFM observations that the surface randomness was improved from 4.54 nm for the ITO single layer to 2.89 nm for the ITO + AZO (120 nm) structure.