DIELECTRIC-PROPERTIES OF SRTIO3 THIN-FILMS GROWN BY OZONE-ASSISTED MOLECULAR-BEAM EPITAXY

Crystalline SrTiO3 thin films were fabricated by an ozone-assisted mol ecular beam epitaxy (MBE) method at a relatively low deposition temper ature of around 300 degrees C. These films had high crystallinity, smo oth surface and insulating properties with increasing deposition tempe rature. The relative dielectric constant for a 250-nm-thick SrTiO3 fil m deposited at 480 degrees C was 825 at 35 K. This value was comparabl e to that of SrTiO3 films, which were deposited at over 650 degrees C by pulsed laser deposition. This film had similar temperature and appl ied electric field dependence to bulk S TiO3. The electric field-effec t evaluation on SrTiO3 films in the Ag/SrTiO3/YBa2Cu3O7-x configuratio n indicated suppression of the SrTiO3/YBa2CU3O7-x interface layer.