Dissociation of grain boundary dislocations in SrBi2Ta2O9 ferroelectric thin films

Zhu, XH Zhu, JM Zhou, SH Li, Q Liu, ZG Ming, NB

Xh. Zhu et al., Dissociation of grain boundary dislocations in SrBi2Ta2O9 ferroelectric thin films, APPL PHYS L, 79(9), 2001, pp. 1345-1347

14

INGLESE

Article

Apllied Physucs/Condensed Matter/Materiales Science

APPLIED PHYSICS LETTERS

0003-6951 → ACNP

79

9

2001

1345 - 1347

ISI

0003-6951(20010827)79:9<1345:DOGBDI>2.0.ZU;2-2

In this work, the dissociation of grain boundary dislocations (GBDs) is rep orted in SrBi2Ta2O9 (SBT) ferroelectric thin films with c-axis orientation grown by pulsed-laser deposition on Pt/TiO2/SiO2/Si(100) substrates. Small- angle (8.2 degrees) [001] tilt grain boundaries with a boundary plane close to the (110) plane exhibit partial GBDs separated by stacking faults. The dissociated grain-boundary structures have twice the number of GBDs and int erdislocation core channel width smaller than that Frank's geometrical rule predicts. At the equilibrium, the repulsive elastic force between partial dislocations is balanced by an attractive force produced by the formation o f a stacking fault between the partials. Based on this, the stacking fault energy is evaluated to be 0.27-0.29 J/m2. The relationship between the leak age current of SBT films and dissociation of GBDs is also discussed. (C) 20 01 American Institute of Physics.