Statistical comparative analysis of microwave and conventionally annealed sol–gel derived metal oxide thin films

The impact of conventional furnace annealing and microwave annealing on sol-gel-derived TiO₂ and NiTiO₃ thin film was comparatively investigated on a statistically supported framework. The deposition of thin films was done through spin coating, and then heat treatment was done through the two different routes under controlled conditions. XRD, SEM, AFM, UV-visible spectroscopy, C-V, and I-V measurements were systematically used to analyse the structural, morphological, optical, dielectric, and electrical properties. To evaluate the reproducibility and reliability, statistical methods such as the analysis of mean-standard deviation and testing of significant results were used. Microwave annealing produced statistically significant changes in crystallite size and optical band gap and leakage current density compared to conventional annealing, with visible transmittance and dielectric constant being statistically similar. The behaviour that was dependent on the material was seen, especially the roughness of the surface and crystallite evolution. In general, the findings indicate that microwave annealing can be as efficient as, or even superior to, conventional annealing with shorter processing times, making it a viable alternative to the post-deposition heat treatment of sol-gel-made metal oxide thin films.