Dielectric Properties of SrTiO3 Thin Films Grown by Ozone-Assisted Molecular Beam Epitaxy

Abstract
Crystalline SrTiO3 thin films were fabricated by an ozone-assisted molecular beam epitaxy (MBE) method at a relatively low deposition temperature of around 300° C. These films had high crystallinity, smooth surface and insulating properties with increasing deposition temperature. The relative dielectric constant for a 250-nm-thick SrTiO3 film deposited at 480° C was 825 at 35 K. This value was comparable to that of SrTiO3 films, which were deposited at over 650° C by pulsed laser deposition. This film had similar temperature and applied electric field dependence to bulk SrTiO3. The electric field-effect evaluation on SrTiO3 films in the Ag/SrTiO3/YBa2Cu3O7- x configuration indicated suppression of the SrTiO3/YBa2Cu3O7- x interface layer.