LASER-ABLATION GROWTH AND ELECTRICAL-PROPERTIES OF FERROELECTRIC BISMUTH TITANATE THIN-FILM

Bismuth titanate, Bi4Ti3O12 thin films have been deposited on Si, and Pt substrates by the single step and the 3-step methods of laser ablat ion at comparatively low temperatures of 400 degrees C similar to 500 degrees C and following annealing treatment. Preferential (117) orient ed films have been obtained on Si substrates by deposition at 400 degr ees C and annealing at 550 degrees C. Dielectric hysteresis loops have been observed in all the BIT films on Si. Polarization at zero applie d voltage and Electric field at zero polarization in the film deposite d on Si substrates at 400 degrees C and annealed at 550 degrees C by t he single step method are 18.5 mu C/cm(2) and 40 KV/cm, respectively. The values in the film deposited on Si substrates at 400 degrees C and annealed at 550 degrees C by the 3-step deposition method are 8.6 mu C/cm(2) and 14.5 KV/cm, respectively. Current density-voltage characte ristics of BIT films deposited on Si by the 3-step method show good in sulation as the leakage current is very small (< 10(-7) A/cm(2) at -5 similar to 5 V).