Residual Stress Analysis of Pt Bottom Electrodes on ZrO₂/SiO₂/Si and SiO₂/Si Substrates for Pb(ZrTi)O₃ Thick Films

Abstract

We fabricated Pt bottom electrodes on SiO 2 /Si and ZrO 2 /SiO 2 /Si substrates by DC magnetron sputtering. The residual stress of the Pt layers deposited on SiO 2 and ZrO 2 /SiO 2 diffusion barrier layers was measured by an X-ray diffractometer (XRD). The Pt layers deposited at 400°C exhibited tensile residual stress, but the Pt layers deposited at room temperature exhibited compressive residual stress. Lead zirconate titanate (PZT) thick films were fabricated on the Pt electrodes by a screen printing method. The dielectric permittivity, tan δ, P – E hysteresis loop, breakdown field, coercive field and piezoelectric constant were measured for the PZT thick films. A PZT thick film on Pt/ZrO 2 /SiO 2 /Si displaying a low tensile residual stress exhibited the remanent polarization, coercive field, dielectric permittivity ( ε r ), dissipation factor (tan δ), breakdown field and piezoelectric constant ( d 33 ) of 13 µC/cm 2 , 8.5 kV/cm, 800, 0.015, 12 MV/m and 343 µC/N, respectively.