Thickness effect on the structure, grain size, and local piezoresponse of self-polarized lead lanthanum zirconate titanate thin films

摘要: Polycrystalline lanthanum lead zirconate titanate (PLZT) thin films were deposited on Pt/TiO2/SiO2/Si substrates to study the effects of thickness and grain size their structural piezoresponse properties at nanoscale. Thinner PLZT show a slight (100)-orientation tendency that tends random orientation for thicker film, while microstrain crystallite increases almost linearly with increasing thickness. Piezoresponse force microscopy autocorrelation function technique used demonstrate existence local self-polarization effect dependence correlation length. The obtained results ruled out bulk mechanisms suggest Schottky barriers near film-substrate are likely responsible build-in electric field in films. Larger length evidence this number coexisting polarization directions larger grains leading an alignment macrodomains thinner