BaTiO_3/γ-Fe_2O_3颗粒膜的介电性质和磁电性质

Dielectric and magnetoelectric properties of BaTiO_3/γ-Fe_2O_3 granular films

本文利用高真空磁控——离子束复合溅射系统在单晶n型Si(100)面上生长了Ag/[BaTiO3/?-Fe2O3]/ZnO结构的复合薄膜,对比研究了BaTiO3/γ-Fe2O3颗粒膜在真空退火温度300°C,400°C和500°C下的介电性质、磁性质以及铁电特性.实验研究发现,随着退火温度的升高,样品的电容和介电常数逐渐变大,在500°C退火的样品,其电容为633.93 pF,介电常数为10.233.所有样品都具有良好的铁磁性和铁电性,其中在400°C退火的样品具有最大的饱合磁化强度103.3 emμ/cm3,而在500°C时具有最大的剩余电极化强度9.13?10?1μm/cm2.同时,在零磁场和1.0 T的磁场下,矫顽电场和剩余电极化强度都没有明显的变化.在200 K时,电滞回线却发生了明显的变化.

Composite films of Ag/BaTiO3/γ-Fe2O3 ZnO structure were grown on an n-type silicon （100） single crystal substrate by high vacuum magnetron-ion beam composite sputtering system in this article. The comparative study of dielectric and magnetic along with ferromagnetic properties of BaTiO3/γ-Fe2O3 granular films at annealing temperature is 300℃, 400℃ and 500℃ respectively. Experimental investigation shows that it have high capacitance and large dielectric constant, namely, capacitance of 633.93 pF and dielectric constant of 10.233 under 500℃ annealing condition. All the samples are good ferromagnetic and ferroelectricity, however, it have largest saturated magnetic moment of 103.3 cm/cm^3 and remanent electric polarization of 9.13×10^-1 gm/cm^2 under 400℃, 500℃ annealing condition respectively. At the same time, the coercive electric field and the remanent electric polarization have no obvious change when magnetic fields are 0 T and 1.0 T. At 200 K, the hysteresis loop has obvious change when magnetic field is 0.5 T.