Property comparison between tantalum and tungsten doped polycrystalline VO2 thin films

Vanadium dioxide films doped tantalum and tungsten were deposited on SiO₂/Si substrate by modified Ion Beam Enhanced Deposition (IBED) method. The doped polycrystalline VO₂ films have single (002) orientation. The phase transition temperature was 28degC and 42degC for W and Ta doping respectively. The TCR was -3.4%/K and -10.14%/K at 300 K for V_0.97W_0.03O₂ and V_0.97Ta_0.03O₂ respectively. Experimental results shown the crystal lattice constant d was elongated about 0.34% and 0.24%, phase transition hysteresis was 2.1degC and 1.2degC, the resistivity change magnitude was 1.6 and 1.2 for W-and W-and W-and Ta-doped IBED VO₂ films respectively.