Effect of La Doping on ZnO Thin Films by Spray Pyrolysis

Abstract

In this study, Zinc oxide (ZnO) undoped and Lanthanum doped (ZnO: La) thin films were deposited on 400°C heated glass using spray pyrolysis technique with moving nozzle. The components (Zn (CH3COO)2, 2H2O) and (LaCl3, 7H2O) were used as sources to produce ZnO thin film and doped Lanthanum, respectively. Effects of dopant on the optical and structural properties of undoped and 0, 2 and 4 wt. % Lanthanum doped ZnO thin films were studied. Optical transmittance spectra of the films showed high transparency of about 98% in visible region. The optical gap for ZnO and 0, 2 and 4 wt. % La doped ZnO thin films were found to be in 3.25-3.28 [eV] range. The X-ray diffraction showed that the thin films have hexagonal wurtzite structure with a strong (002) as preferred orientation, whereas the crystalline size was ranged in 15.89-33.45 nm. The ZnO thin films are promising to be used a light emitting diodes, gas sensor and UV detectors applications.

Effect of Lanthanum Doping on the Structural, Morphological, and Optical Properties of Spray-Coated ZnO Thin Films

“…The shift in the absorption edge of Zn0.95La0.05O films confirms the better optical properties. The Tauc's plot relation [12] was used to determine the bandgap.…”

“…The yellow-orange emission was found to be maximum for pure ZnO films due to increased oxygen-related defects. The Tauc's plot relation [12] was used to determine the bandgap.…”