Improved ferroelectric properties of Pb(Zr0.52,Ti0.48)O3 thin film on single crystal diamond using CaF2 layer

The authors report the integration of perovskite Pb(Zr0.52,Ti0.48)O3 thin film on single crystal diamond by using a nonoxide single CaF2 buffer layer. The CaF2 buffer layer plays a dual role in the lead zirconate titanate Pb(Zr,Ti)O3 (PZT) film deposition. The first is that the CaF2 layer leads to a preferentially (100)-oriented PZT thin film on diamond, improving the ferroelectric properties significantly. The PZT film exhibits a remanent in-plane polarization of 2Pr=68 μC/cm2 and a coercive field of 33 kV/cm. The remanent polarization is much larger than that of PZT films deposited on diamond by using SrTiO3/Al2O3 buffer layer. The second is that the CaF2 layer acts as an efficient energy barrier for the metal-ferroelectric-insulator-diamond capacitor due to its wide band gap. The leakage current in the capacitor is reduced to be lower than 10−6 A/cm2 in the forward bias mode.