Comparative Study of Structural, Optical and Electrical Properties of SnO<sub>2</sub> Thin Film Growth via CBD, Drop-Cast and Dip-Coating Methods

Tin oxide (SnO2) thin films were deposited on glass substrate by Chemical Bath Deposition (CBD), Drop-Cast and Dip-Coating method. The thin films were post-annealed at 500°C for 2 hours. The structural, optical, and electrical properties of the SnO2 thin films were investigated by using XRD, FTIR, SEM, EDX, UV-Vis spectroscopy, and Electrometer experiment. The XRD patterns of SnO2 thin films deposited on glass substrate by CBD method, Drop-Cast method and Dip-Coating method showed cubic, tetragonal and amorphous structures respectively. The FTIR spectrum exhibited the strong presence of SnO2 with the characteristic vibrational mode of Sn-O-Sn. The SEM analysis was observed that the surface morphology of the thin films toughly depends on the deposition methods of the SnO2 thin films. EDX measurement confirmed that the thin films are the composition of Tin (Sn) and Oxygen (O2). The optical band gap of SnO2 thin films deposited by CBD method, Drop-Cast method and Dip-Coating method is found to be 3.12 eV, 3.14 eV and 3.16 eV respectively. Thin films deposited by Dip-Coating method showed the highest band gap. The electrical results confirmed that the SnO2 thin films are good conductors and pursued Ohm’s Law. These properties of the SnO2 thin films brand are appropriate for application in solar cell assembly, gas sensor devices and transparent electrodes of panel displays.