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 (T-s) ranging from 300 to 450 degrees C. The loss in remnant polarization (P-r) and coercive field (E-c) is found to be less than 17% after 10(10) switching cycles when T-s is higher than 350 degrees C. It is also suggested that the leakage current is reduced when T-s increases up to a temperature of 400 degrees C. However, PST films deposited at 450 degrees C may produce serious Pb-O volatilization, resulting in the deterioration of the crystallinity and high leakage currents. As a result, the 400 degrees C-deposited PST film reveals the lowest leakage current, nearly fatigued-free J-E characteristics after 10(10) switching cycles, and the best breakdown property, attributed to the enhanced crystallinity and low concentration of defects.