Epitaxial Ba0.6Sr0.4TiO3 films were grown onto (001) LaAlO3 by pulsed-laser deposition, and the dislocation structures of the films were investigated by using transmission electron microscopy. Misfit dislocations with a periodicity of about 7nm and Burgers vectors b = a<100> were observed at the interface. A high density of threading dislocations was present the films and these also had b = a<100>. The data indicated that the threading dislocations were not generated as the result of half-loop climb from the deposit surface as proposed previously, but were instead formed when misfit dislocations were forced away from the interface during island coalescence.

Threading Dislocation Generation in Epitaxial (Ba,Sr)TiO3 Films Grown on (001) LaAlO3 by Pulsed Laser Deposition. I.B.Misirlioglu, A.L.Vasiliev, M.Aindow, S.P.Alpay, R.Ramesh: Applied Physics Letters, 2004, 84[10], 1742-4