Characterization of MgO thin film prepared by spray pyrolysis technique using perfume atomizer

摘要

Transparent conducting magnesium oxide (MgO) thin films are obtained by pyrolytic decomposition of magnesium acetate in a mixture of ethanol and distilled water on to a glass substrate using perfume atomizer. The substrate temperature (T_s) is maintained at 300 °C, 350 °C, 400 °C, and 450 °C for depositing the films and annealed at 450 °C for 4 h. Then the samples were characterized by X-ray diffraction, field emission scanning electron microscope, atomic force microscope, UV-Vis spec-troscopy, photoluminescence analyzer, and Raman spectrophotometer for identifying its structure, morphology, topography, bandgap and defect states. The XRD result demonstrates the cubic, polycrystalline nature with (200) preferred orientation. The presence of MgO_2 phase along (2 2 2) plane increases with substrate temperature is noticed. From the SEM monograph, the clusters of spherical grains are observed for all the films and the columnar growth of the MgO film is observed from the AFM topographical image. The surface roughness tends to increase with substrate temperature. The MgO thin films possess two absorption bands and two optical bandgaps. The transmittance of 70% is obtained for MgO film which could be used for optoelectronic device and protective coating applications. The blue and green emission bands are identified from the PL spectrum. The defects in the film are responsible for linear I-V characteristic and the large forward current value implies higher efficiency for solar cell applications.