Dielectric and Ferroelectric Properties of Er_2O_3-doped Bi_4Ti_30_(12) Thin Films

摘要

Er_2O_3-doped bismuth titanate (Bi_(4-x)Er_xTi_3O_(12), BET) and pure Bi_4Ti_3O_(12) (BIT) thin films with random orientation were fabricated on Pt/Ti/SiCVSi substrates by rf magnetron sputtering technique. These samples had polycrystalline Bi-layered perovskite structure without preferred orientation, and consisted of well developed rod-like grains with random orientation. Er-doping into BIT caused a large shift of the Curie temperature ( T_c ) from 675 °C to lower temperature and a improvement in dielectric property. The experimental results indicated that Er doping into BIT also result in a remarkable improvement in ferroelectric property. The P_r and the E_c values of the BET film with x=0.75 were 21 μC/cm~2 and 80 kV/cm, respectively.