W-substituted Bi4Ti3O12 (BIT), Bi4(Ti3-xWx)O12, films were prepared on (111)Pt/IrO2/SiO2/Si substrates at 600°C by metalorganic chemical vapor deposition (MOCVD). The degree of (117) orientation and the lattice spacing of 117 Bi4(Ti3-xWx)O12 increased with increasing W content up to x = 0.25. Ferroelectricity was hardly observed in as-deposited films but confirmed in the films after annealing at 700° C. The coercive field (Ec) monotonically increased with increasing W content, but the remanent polarization (Pr) showed a maximum value at x = 0.11. PT and Ec of Bi4(Ti2.89W0.11)O12 thin film after heat treatment was 13 μC/cm2 and 160kV/cm, respectively. W-substituted films showed high fatigue resistance against continuous switching up to 8 × 1010 cycles. These results show that W substitution for BIT film is effective in improving the ferroelectricity.
|Number of pages||3|
|Journal||Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers|
|Issue number||5 A|
|Publication status||Published - 2003 May|
- Tu ngsten
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)