Various vanadium-oxide thin films were deposited by e-beam and thermal evaporation of V2O5, V2O3, and VO2 powders. Films with thickness of $2000AA$ were subjected to annealing at $300^{circ}C$~$450^{circ}C$ in N2 atmosphere for the crystallization and desification purposes. For the films deposited from V2O5 and VO2 sources, sources, Magneli (VnO2n-1$ 4leq$ $nleq$ 8) and VO2 phase appeared at $300^{circ}C$, respectively, but VO2 phase also transformed into Magneli phase at $450^{circ}C$ by severe reduction. On the contrary, VO2/VO mixed phases resulted from congruent evaporation of V2O3 unchanged after the same annealing treatment due to the balanced reduction and oxidation of VO2 and VO whcih have different equilibrium O2 pressures. It is suggested that the annealing in the controlled oxidation atmosphere or the deposition using mixed oxide sources are necessary to get the film containing VO2 phase.
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