Polarization Degradation and Breakdown of Pulse-Laser-Deposited (Pb,Sr)TiO3 Films at Low Temperatures

Abstract

(Pb,Sr)TiO3 (PST) films were deposited on Pt/SiO2/Si by pulsed laser deposition at low substrate temperatures (Ts) ranging from 300 to 450 °C. The loss in remnant polarization (Pr) and coercive field (Ec) is found to be less than 17% after 1010 switching cycles when Ts is higher than 350 °C. It is also suggested that the leakage current is reduced when Ts increases up to a temperature of 400 °C. However, PST films deposited at 450 °C may produce serious Pb–O volatilization, resulting in the deterioration of the crystallinity and high leakage currents. As a result, the 400 °C-deposited PST film reveals the lowest leakage current, nearly fatigued-free J–E characteristics after 1010 switching cycles, and the best breakdown property, attributed to the enhanced crystallinity and low concentration of defects.