We report a solid-phase epitaxial approach that overcomes the difficulty of synthesizing ${\mathrm{V}}_2{\mathrm{O}}_3$ films with bulk-like electrical properties. The synthesis method consists of highly reproducible processes in which amorphous precursor $\mathrm{V}{\mathrm{O}}_x$ films are deposited on $\alpha \text{−}{\mathrm{Al}}_2{\mathrm{O}}_3$ substrates at room temperature and subsequently annealed $\mathit{ex}$ situ in an ${\mathrm{H}}_2$ atmosphere. By optimizing the annealing temperature to $600–800{}^{\circ }\mathrm{C}$, the ${\mathrm{V}}_2{\mathrm{O}}_3$ films exhibited a clear metal–insulator transition (MIT) at approximately 160 K with a resistivity jump of nearly six orders of magnitude. The MIT characteristics are comparable to the MIT properties of stoichiometric bulk ${\mathrm{V}}_2{\mathrm{O}}_3$ and high-quality films grown directly using conventional physical vapor deposition methods. X-ray diffraction measurements confirmed epitaxial growth of the films on isostructural $\alpha \text{−}{\mathrm{Al}}_2{\mathrm{O}}_3$ substrates with $a$-, $c$-, and $m$-plane orientations. Our study establishes a reproducible route for synthesizing ${\mathrm{V}}_2{\mathrm{O}}_3$ films with robust MIT characteristics for Mott-transition-based electronic devices.

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• Crystal growth
• Electrical conductivity
• Electrical properties
• Metal-insulator transition
• Phase transitions