We fabricated 18O-exchanged SrTi18O0.03x 16O0.03(100-x) (STO18) thin films on SrTi 16O3(001) single-crystal substrates by pulsed laser deposition from a SrTi18O3 single-crystal target at various growth temperatures and 16O2 partial pressures. The diffusion of 16O from the substrate could be successfully suppressed by growing films under high 16O2 partial pressures, and a homogeneously 18O-exchanged STO18 thin film (x=60) was then obtained. The STO18 film became ferroelectric at a critical temperature higher than that expected from the corresponding STO18 bulk sample by ∼10 K, at which the Raman spectra suggested that the first-order transition occurred, different from the case of the STO18 bulk.
ASJC Scopus subject areas
- Physics and Astronomy(all)