Electric and Magnetic Properties of a CoFe2O4/PZT Bilayer Grown on (100)SrTiO3 by Using PLD

We have investigated the electric and the magnetic properties of a ferrimagnetic and ferroelectric bilayer CoFe2O4(CFO)/PbZr0.2Ti0.8O3 (PZT) grown on a (100)SrTiO3(STO) substrate by using pulsed laser deposition. PZT (100 nm) and CFO (70 nm) layers were sequentially deposited on the (100)STO substrate with a bottom electrode LaNiO3(50 nm) layer at 600-650 degrees C. X-ray diffraction for the PZT layer exhibited both (200) and (002) peaks, which are due to the c- and the a-domains, and a decrease of tetragonality after CFO deposition. The electric properties of the CFO/PZT bilayer were characterized by using P-V loop, C-f, and C-V measurements. The remnant polarization and coercivity were slightly decreased after the top-layer CFO deposition while fatigue behavior was distinctively improved. The M-H loop measurement confirmed that the CFO layer possessed a typical ferrimagnetic property at room temperature.