Epitaxial growth of (103)-oriented ferroelectric SrBi2Ta2O9 thin films on Si(100)

Abstract

Non-c-axis-oriented ferroelectric ${\mathrm{SrBi}}_2{\mathrm{Ta}}_2{\mathrm{O}}_9$ (SBT) epitaxial thin films with (103) orientation have been grown by pulsed laser deposition on buffered Si(100) substrates. For the buffer layers, a heterostructure consisting of MgO(111)/YSZ(100)/Si(100) was applied to induce the growth of a (111)-oriented ${\mathrm{SrRuO}}_3$ (SRO) bottom electrode. X-ray diffraction $\text{θ–2θ}$ and $\phi$ scans revealed well-defined orientation relationships, viz. SBT(103)∥SRO(111)∥MgO(111)∥YSZ(100)∥Si(100); SBT[010]∥SRO[0$\text{1̄}$ 1]∥MgO[0$\text{1̄}$ 1]∥YSZ〈001〉∥Si〈001〉. The ferroelectric measurements of the (103)-oriented SBT films showed a remanent polarization ${\mathrm{(P}}_r)$ of 5.2 $\mu {\mathrm{C/cm}}^2$ and a coercive field ${\mathrm{(E}}_c)$ of 76 kV/cm for a maximum applied electric field of 440 kV/cm.