Dislocation arrays and dislocation half-loops in BaTiO3 thin films were characterized by using transmission electron microscopy. BaTiO3 films with thicknesses ranging from 2 to 20nm were grown on (100) SrTiO3 by reactive molecular beam epitaxy. The critical thickness for dislocations to occur in this system was found to lie between 2 and 4nm. The misfit dislocations were mainly <100> type. The average spacing between the dislocations in the array became smaller when the film was thicker, which indicated gradual relaxation of mismatch strain with increasing film thickness.

Evolution of Dislocation Arrays in Epitaxial BaTiO3 Thin Films Grown on (100) SrTiO3. H.P.Sun, W.Tian, X.Q.Pan, J.H.Haeni, D.G.Schlom: Applied Physics Letters, 2004, 84[17], 3298-300