Fatigue-free La-modified PbTiO3 thin films prepared by pulsed-laser deposition on Pt/Ti/SiO2/Si substrates

Fatigue-free 14 mol % La-modified PbTiO3 (PLT) thin films were grown on Pt/Ti/SiO2/Si substrates using pulsed-laser deposition and crystallized by furnace annealing at 600 degreesC. The 220-nm-thick PLT film capacitors with a Pt top electrode showed excellent ferroelectric properties. The remanent polarization (2P(r)) and the coercive field (2E(c)) were about 20 muC/cm(2) and 70 kV/cm, respectively, and the PLT capacitors did not show any noticeable fatigue up to 3x10(9) read/write switching cycles at a frequency of 1 MHz and switching voltage of 5 V. By comparing the microstructures, electric, and dielectric properties with those of pure PbTiO3 thin films, the suppression of oxygen vacancies and/or charged defects, and the coral-like microstructures developed in PLT films were attributed to its fatigue-free feature. (C) 2003 American Institute of Physics.