Low-temperature crystallization of SrBi_2Ta_2O_9 thin films with Bi_2O_3 interfacial layers by liquid-delivery metalorganic chemical vapor deposition

摘要

Ferroelectric SrBi_2Ta_2O_9 (SBT) thin films and Bi_2O_3 interfacial layers were deposited onto the Pt/Ti/SiO_2/Si substrates via liquid-delivery metalorganic chemical vapor deposition. The SBT films with a 5-nm-thick Bi_2O_3 interfacial layer were well crystallized without c-axis orientation, even at deposition temperature of 540 deg C and showed a stronger (115) orientation than those without a Bi_2O_3 layer with increasing annealing temperature. The remanent polarizations of SBT films with Bi_2O_3 interfacial layer were significantly improved in comparison with those without Bi_2O_3 layer. The remanent polarization (2P_r) and coercive field (E_c) of SBT films without and with a Bi_2O_3 interfacial layer annealed at 750 deg C were 12 and 21 #mu#C/cm~2 and 60 and 38 kV/cm, respectively, at an applied voltage of 5 V.