Thickness Dependence of Residual Stress in Alkoxide-Derived Pb(Zr0.3Ti0.7)O3 Thin Film by Chemical Solution Deposition

Abstract

Ferroelectric thin films of Pb(Zr0.3Ti0.7)O3 (PZT30) with different thicknesses were deposited on a Pt/Ti/SiO2/Si substrate by chemical solution deposition (CSD). The residual stress in the PZT30 thin films was estimated by the phonon mode shift of Raman scattering. The stress dependence of the optical phonon mode of ferroelectric tetragonal PZT30 was calibrated by a gasketed diamond anvil cell (DAC) system. As a result, the A(2TO) mode for PZT30 was downshifted at a rate of 13.9 cm-1/GPa. By using this calibration result, the residual stress in the PZT30 thin films with different thickness was estimated. The residual stress in PZT30 thin films increased with decreasing film thickness and reached approximately 1.14 GPa in the case of a film 280 nm thick. Moreover, the residual stress in the PZT30 thin films was compared with that of a lead titanate (PT) thin film to discuss the origin of the residual stress.