Misfit dislocation arrays at the interface between La_0.9Sr_0.1MnO₃ films and vicinal SrTiO₃(001) substrates

Abstract

The microstructural characteristics of misfit dislocations at the interface between La_0.9Sr_0.1MnO₃ films and vicinal SrTiO₃ substrates have been studied by transmission electron microscopy. The misfit dislocations were determined to be edge type with Burgers vector Owing to the inclination of the substrate, the dislocation line along the miscut direction of the substrate is rotated. The deviation angle of the dislocation line away from the miscut direction of the substrate varies with the miscut angle. As a result, the dislocation arrays at the interface form a parallelogram dislocation network rather than an orthogonal network. A simple explanation of the misfit dislocation reaction with the step for the film on a vicinal substrate is proposed to interpret the rotation of the dislocation line along the miscut direction.

Acknowledgments

This work was supported by the National Outstanding Young Scientist Foundation for X. L. Ma with Grant No. 50325101 and Special Funds for the Major State Basic Research Projects of China (Grant No. 2002CB613503).