[14p-2H-1~15] 6.3 Oxide electronics

[14p-2H-10] Phase transition properties and c/a ratio in pulsed laser-deposited V₂O₃ thin films

〇Joe Sakai¹, Patrice Limelette¹, Hiroshi Funakubo² (1.GREMAN, Univ. Tours, 2.Tokyo Tech)

Keywords:vanadium oxide,metal-insulator transition,lattice strain

We prepared V₂O₃ thin films under various conditions by a pulsed laser deposition method on C- or R-plane Al₂O₃ substrates. The relationship between c/a ratio and transport properties of these films was studied. X-ray diffraction analyses confirmed that V₂O₃ films were epitaxially grown on both C- and R-planes under Ar gas ambient at 873 K. On C-plane Al₂O₃, c/a ratios of (0001)-oriented V₂O₃ films ranged from 2.80 to 2.88. The (0001)-oriented films with 2.80 ≤ c/a ≤ 2.83 showed complex M-I-M transition during cooling from 300 to 10 K, while larger c/a ratios were accompanied by metallic properties throughout this temperature range. Generally, films on R-plane Al₂O₃ underwent more drastic M-I transition than films on C-plane.