STRUCTURAL AND ELECTRICAL-PROPERTIES OF FERROELECTRIC BISMUTH TITANATE THIN-FILMS PREPARED BY THE SOL-GEL METHOD

Crystalline bismuth titanate films were fabricated using a modified so l gel method. The process was simplified using stock titanium and bism uth solutions. Films were fabricated using rapid thermal processing wi th a ramp rate of 100 degrees C/s to 700 degrees C for 30 s. The avera ge grain size of films was 175 nm. A dielectric constant in the typica l range of 220 and tan delta of 0.01 were measured. P-E hysteresis loo ps were observed with the ferroelectric properties of P-s = 22 mu C/cm (2), P-r = 10 mu C/cm(2) and the coercive force E(c) = 165 kV/cm. The leakage current density was of the order of 10 nA/cm(2) at 60 kV/cm. A n almost flat C-V characteristic and a charge storage density of 42 fC /mu m(2) at 220 kV/cm were measured.