Influence of growth duration and nitrogen-ambient on the morphological and structural properties of beta-gallium oxide micro- and nanostructures

Micro- and nanostructures of gallium oxide (Ga2O3) were prepared on silicon substrate by the hydrogen-reduction chemical vapor deposition (HR-CVD) technique. We investigated the influence of synthesis duration and growth ambient on the surface morphology, crystal structure and band gap of the grown films by using field emission electron microscope (FESEM), high resolution X-ray diffraction (HR-XRD) and ultraviolet–visible spectrophotometer (UV–vis), while elemental composition was confirmed by energy dispersive X-ray spectroscopy (EDS). Dwell time was found to enhance step coverage of the substrate and also improve the X-ray diffraction peaks. Films fabricated under nitrogen-flowing ambient were observed to have regular shape but with less dense structures, lower Ga/O atomic ratio, weaker XRD peak intensity, and increasing band gap; while samples deposited in N2-deficient environment had characteristics opposite to those of their counterpart. Band gap of films were observed to decrease with increasing film density and Ga/O atomic ratio. •Micro- and nanostructures of β-Ga2O3 were synthesized via hydrogen-reduction CVD.•Effects of growth time and gas-phase chemistry on β-Ga2O3 NSs.•Ga/O atomic ratio on films show strong effect on XRD peak intensity and film density.•The density of β-Ga2O3 NSs has significant influence on bandgap.