The interfaces of high-quality superlattices were investigated by means of high-resolution transmission electron microscopy. This revealed that the superlattices exhibited atomically sharp interfaces between the oxide layers; with no interdiffusion. An intermediate layer (about 1nm thick) with many defects, which was caused by surface steps and dislocations at the SrTiO3 substrate, was observed at the film/substrate interface. However, the film did not contain large extended defects. This was achieved by forming c/3 or 2c/3 step stacking faults at the substrate surface steps.

Y.J.Li, G.C.Xiong, G.J.Lian, J.Li, Z.Z.Gan: Materials Science Forum, 1995, 189-190, 381-6