Enhanced dielectric and piezoelectric properties of RF sputtered Pb(Zr0.60,Ti0.40)O3 thin films deposited on sol-gel derived Pb1+x(Zr0.40,Ti0.60)O3 seed layer with various lead contents

Lead zirconate titanate (Pb(Zr_0.60Ti_0.40)O₃) thin films were deposited on Pt/Ti/SiO₂/Si (100) substrates by radio frequency (RF) magnetron sputtering method based on sol-gel derived Pb_1+x(Zr_0.40,Ti_0.60)O₃ (x = 0.1, 0.15, 0.2, 0.25, 0.3) seed layer. X-ray diffraction (XRD) analysis shows that the degree of (100) preferred orientation first increased and then decreased with increased x values. Scanning electron microscope (SEM) analysis shows the films with seed layer exhibited dense perovskite structure. X-ray photoelectron spectroscopy (XPS) analysis reveals that x value had a significant influence on the oxygen vacancies and chemical state of lead element. Optimal dielectric properties with a permittivity of 916.4 and a loss factor of 0.027 at 100 Hz were obtained in PZT film with a seed layer of x = 0.2. A symmetric hysteresis loop with a larger remnant polarization 2P_r (39.2 μCcm⁻²) and relatively lesser 2E_c (109 kVcm⁻¹) was obtained in film deposited on a Pb_1.2(Zr_0.40,Ti_0.60)O₃ seed layer. Moreover, the film with a seed layer of x = 0.2 exhibited excellent piezoelectric properties.