Preparation and Properties of $\text{Ga}2\mathrm{O}_{3}$ Thin Films by Sol-Gel Method

Gallium oxide <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(\text{Ga}_2\mathrm{O}_{3})$</tex> is a promising wide-bandgap semiconductor with a 4.9 eV bandgap, making it suitable for advanced power electronics and UV solar-blind photodetectors. Our research focuses on <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\beta-\text{Ga}_{2}\mathrm{O}_{3}$</tex> thin films fabricated using a cost-effective sol-gel method. We find that higher precursor concentrations optimize film quality, as indicated by improved crystallinity and reduced grain size variability. X-ray diffraction (XRD) analysis showed that the crystallinity of the <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\beta-\text{Ga}2\mathrm{O}3$</tex> film increased, the grain size increased, and the full width at half maximum (FWHM) decreased by selecting the appropriate precursor concentration. Scanning electron microscopy (SEM) serves as a primary tool for examining the elemental composition and surface topography of the samples. Complemented by energy-dispersive X-ray spectroscopy (EDS), a sophisticated analytical technique, we further delineate the elemental profiles of the samples with precision. The synergy of SEM and EDS provides a comprehensive assessment of the sample characteristics, ensuring accurate determination of their elemental constituents. The ultraviolet-visible (UV-Vis) spectrophotometer, an instrument of high precision, is utilized in this study to ascertain the spectral properties of samples within the ultraviolet to visible light spectrum. Specifically, it measures sample transmittance and absorptivity, from which the optical band gap is calculated.