| Title |
Structural and Electrical Properties of Vanadium Oxide Thin Films Annealed in Vacuum |
| Authors |
최복길(Choi Bok-Gil) ; 최창규(Choi Chang-Kyu) ; 권광호(Kwon Kwang-Ho) ; 김성진(Kim Sung-Jin) |
| Keywords |
Vanadium Oxide ; Thin Films ; Sputtering ; Vacuum Annealing ; Sensor |
| Abstract |
Thin films of vanadium oxide(VO/sub x/) were deposited by r.f. magnetron sputtering from V₂O/sub 5/ target with oxygen/(oxygen+argon) partial pressure ratio of 0% and 8% and in situ annealed in vacuum at 400℃ for 1h and 4h. Crystal structure, chemical composition, molecular structure, optical and electrical properties of films were characterized through XRD, XPS, RBS, FTIR, optical absorption and electrical conductivity measurements. The films as-deposited are amorphous, but 0%O₂ films annealed for time longer than 4h and 8% O₂ films annealed for time longer than 1h are polycrystalline. As the oxygen partial pressure is increased the films become more stoichiometric V₂O/sub 5/. When annealed at 400℃, the as-deposited films are reduced to a lower oxide. The optical transmission of the films annealed in vacuum decreases considerably than the as-deposited films and the optical absorption of all the films increases rapidly at wavelength shorter than about 550nm. Electrical conductivity and thermal activation energy are increased with increasing the annealing time and with decreasing the oxygen partial pressure. |