Structural, optical and electrical properties in (ZnO/Nb)3/ZnO multilayers system and ZnO-Nb co-deposition

Abstract

The transparent conducting oxides (TCOs) are very studied due to their wide application in solar cells and invisible electronics, in which thin films of ZnO has been great candidates for these systems. However, there is no study of multilayers or ZnO-metal co-deposition systems to improve the optical and electrical properties of the TCOs. In this work, multilayers ZnO/Nb/ZnO/Nb/ZnO/Nb/ZnO thin films and a co-deposition system were fabricated by sputtering in function to Nb thickness. The optical transmission and absorption properties were analyzed revealing transparency greater than 80% and 50% to the device with thicker Nb and greatest Nb thickness respectively. The electrical properties of the samples presented a conduction behavior non-ohmic at low bias voltage and ohmic behavior at high bias voltage. The hysteretic cycle I-V presented antiferroelectric behavior, in which a resistive switching effect could be observed. The results showed that these devices presented a new memory class, the antiferroelectric random access memories (ARAM).