Stress-induced suppression of piezoelectric properties in PbTiO3 : La thin films via scanning force microscopy

resumo

Sol-gel derived polycrystalline La-doped PbTiO3 films are investigated by scanning force microscopy (SFM) in a piezoelectric contact mode. The SFM signal proportional to the effective piezoelectric coefficient, d(eff), is measured inside individual domains as a function of the mechanical force exerted by the SFM tip on the film's surface. It is found that the piezoelectric signal can be fully suppressed under sufficiently high force (similar to20-22 muN). The suppression is qualitatively different for domains of opposite polarities where d(eff) may change its sign depending on the orientation of polarization vector. The piezoelectric hysteresis loops acquired under increasing force gradually shrink with an asymmetric decrease of the piezoelectric coefficients. This leads to a pronounced vertical shift of the loops (d(eff) offset). The obtained results are discussed in terms of the competing electrostatic and piezoelectric contributions to the measured signal and stress-induced polarization instabilities in the vicinity of the SFM tip. (C) 2003 American Institute of Physics.

palavras-chave

FATIGUE

categoria

Physics

autores

Kholkin, AL; Shvartsman, VV; Emelyanov, AY; Poyato, R; Calzada, ML; Pardo, L

nossos autores

Partilhe este projeto

Publicações similares

Usamos cookies para atividades de marketing e para lhe oferecer uma melhor experiência de navegação. Ao clicar em “Aceitar Cookies” você concorda com nossa política de cookies. Leia sobre como usamos cookies clicando em "Política de Privacidade e Cookies".