Effect of vanadium-modification on structural and electrical properties of Sr2Bi4Ti5O18 thin film

Sr 2 Bi 4 Ti 5 O 18 (SBTi) and Sr 2 Bi 4-x / 3 Ti 5-x V x O 18 (x = 0.018, SBTV) films were deposited on Pt/Ti/SiO 2 /Si(100) substrates using a sol-gel method. Structure, morphology and electric properties were investigated systematically. These films were randomly oriented and composed of rod-like grains. The remanent polarization (2P r ) and coercive field (E c ) of SBTi films were 23 μC cm -2 and 71 kV cm -1 , respectively. This value of 2P r was much higher than the reported value of the SBTi thin film prepared by pulse laser deposition. A small content substitution of V 5+ for Ti 4+ was also confirmed to be effective for further improvement in the ferroelectric properties of SBTi films. The V-modified SBTi films showed a very large remanent polarization (2P r ) of 34 μC cm -2 . More importantly, both films showed high fatigue resistance against continuous switching up to 4 x 10 10 cycles and excellent charge-retaining ability up to 4 x 10 4 s.