Effect of annealing temperature on structure-property correlations in Zn2SnO4 nanostructured films for optoelectronics

Abstract

In the present work, the effect of annealing temperature on structural, optical and electrical properties for sol gel synthesized Zn2SnO4 nanostructured films has been investigated for their suitability in optoelectronics. These samples were probed by using XRD, UV-Visible spectroscopy, photoluminescence spectroscopy and Hall measurements. The x-ray diffraction study divulges the polycrystalline nature and phase transition from cubic inverse spinal Zn2SnO4 phase to pervoskite ZnSnO3 phase in the synthesized films. The optical transmission of ∼43 %-73 % in the visible region while the optical gap varies from 3.61-3.95 eV has been observed for the annealed films. The defect related emission peaks at 423, 445 and 481 nm has been observed. The lowest electrical resistivity (5.8 × 10-3 Ω cm) and highest figure of merit (10-3 Ω-1) for the films annealed at 600 °C has been observed. These results are very important for the development of new n-type transparent conductor for various optoelectronic devices.