Observation of sol-gel solid phase epitaxial growth of ferroelectric Pb(Nb,Zr,Ti)O3 thin films on sapphire

Abstract

This letter reports and discusses the observation of sol-gel solid phase epitaxy (SPE) of (110) Pb0.99Nb0.02(Zr0.52Ti0.48)0.98O3 or PNZT(2/52/48) on 3 in. diam (011̄2) sapphire. The epitaxial nature (with at least single crystal-like texture) of these films was ascertained by HRTEM and x-ray diffraction studies, including pole figure analysis. Such PNZT thin films (0.6 μm) were transparent to wavelengths between 0.4 and 5.6 μm, and exhibited an optical band gap and a refractive index (at 0.6328 μm), of 3.6 eV and 2.5–2.6, respectively.