Structural, Morphological, Topographical, Electrical, Optical, and Compositional Properties of Gallium‐Doped Zinc Oxide Thin Films Prepared by the Sol–Gel Technique

Highly textured gallium (Ga) doped zinc oxide (ZnO) nano‐structured thin films were prepared using sol–gel dip coating on a silicon glass substrate. The prepared films were investigated by XRD, XPS, FESEM, EDAX, TEM, Four Point Probe Technique, UV–vis spectrometer, and FTIR, respectively. To tune the desired properties, prepared films were post‐heat‐treated at 450°C. The XRD analysis results revealed that the ZnO:Ga films were polycrystalline with a single‐phase structure, and high‐intensity, sharp peaks were exhibited in preferred orientation along the (101) direction. The elemental composition, chemical state, and binding energies are determined by using XPS. FESEM analysis showed a hierarchically arranged sponge‐like morphology, and EDAX analysis results confirmed the presence of Zn, Ga, and O elements. TEM analysis displayed the hexagon‐like morphology with a particle size of ∼36 nm. The UV–vis spectroscopy confirmed that all the prepared samples showed a good transmittance value greater than 95% in the visible range (400–800 nm) of the electromagnetic spectrum. The result of the four‐probe technique shows the least resistivity of 1.8 × 10 −2 Ωcm. The obtained results of the prepared ZnO:Ga nanostructured thin films have wider usage in photovoltaic cells and optoelectronic devices.