Improved performance of transparent conductive Cu-based GZO multilayer thin films on flexible substrates via two Al2O3 layers and oxygen-containing atmosphere

• Published in: Journal of alloys and compounds 2021-09, Vol.874, p.159949, Article 159949
• Main Authors: Liu, Yang, Zeng, Qingdong, Wang, Boyun, Nie, Changjiang, Ma, Honghua, Yu, Huaqing
• Format: Article
• Language: English
• Subjects: Aluminum oxide; Barrier layers; Cu-based GZO multilayer thin films; Electrical and optical properties; Figure of merit; Flexible substrate; Magnetron sputtering; Multilayers; Optical properties; Oxygen; Photoelectricity; Substrates; Thin films; Zinc oxide
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2021.159949

•Cu-based Ga-doped ZnO (GZO) multilayer thin films with two Al2O3 layers are deposited on flexible PEN substrates.•The multilayer films have a resistivity of 4.24 × 10-5 Ω cm and a sheet resistance of 6.06 Ω/sq..•The average visible transmittance of Al2O3/GZO/Cu/Al2O3/GZO multilayers is higher than 84%.•TThe multilayer films fabricated in argon-oxygen mixtures exhibit the highest figure of merit of 3.03 × 10-2 Ω-1. High performance of transparent conductive Cu-based Ga: ZnO (GZO) multilayer thin films deposited on flexible substrates are achieved by two Al2O3 barrier layers and oxygen. The multilayers exhibit high figure of merit (FOM) of 3.03 × 10−2 Ω−1 with the resistivity of 4.24 × 10−5 Ω cm and sheet resistance of 6.06 Ω/sq., while the average optical transmittance is above 84% in the visible range. The FOM value is the highest among all the reported Cu-based transparent conductive thin films. The influence mechanisms of Al2O3 layers and oxygen on structural, morphological, electrical and optical properties of the multilayer films are also investigated. These results indicate that the insertion of two thin Al2O3 barrier layers and the filling of oxygen during the deposition of GZO layers is an effective way to improve the photoelectric performance of the Cu-based GZO multilayer films.