Electric and magnetic properties of a CoFe₂O₄/PZT bilayer grown on (100)SrTiO₃by using PLD

We have investigated the electric and the magnetic properties of a ferrimagnetic and ferroelectric bilayer CoFe₂O₄(CFO)/ PbZr_0.2Ti_0.8O₃(PZT) grown on a (100)SrTiO ₃(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 °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.