In-depth analysis on Erbium co-doped CdO:Zn films deposited by nebulizer method for opto-electronic applications

Abstract

In the present study, we have analyzed the fabrication of transparent conductive Erbium (Er) co-doped CdO:Zn films by nebulizer spray method (NSP) by adding different Er level from 0 to 1.5 wt%. X-ray diffraction (XRD) pattern confirmed polycrystalline behavior of prepared Er co-doped CdO:Zn films of cubic crystalline system. Surface roughness of the films was slightly decreased from 20 nm to 16 nm. Elemental mapping and energy dispersive analysis of X-ray (EDX) spectra confirm the existence of Cd, O, Zn and Er in 1.5 wt% Er co-doped CdO:Zn film surface. The estimated optical transmittance and band gap value enhanced from 2.62 to 2.96 eV on growing Er doping concentrations. Photoluminescence (PL) spectrum emitted one strong near-band-edge (NBE) emission at ∼ 435 nm for all the Er co-doped CdO:Zn films, signify their better optical quality. Hall Effect measurements evidenced that the Er co-doping provides enhancement on the carrier concentration and reduce the electrical resistivity. The quality factor of Er co-doped CdO:Zn film thin film was increased from 1.1 × 10−4 (Ω−1) to 11.0 × 10−4 (Ω−1) for increasing the Er doping concentration from 0 to 1.5 wt%.