材料期刊网

The microstructure of ferroelectric [PbZr(x)Ti(1-x)O(3)/PbZr(y)Ti(1-y)O(3)](n) epitaxial multilayers (x/y 0.2/0.4, 0.4/0.6) deposited on SrRuO(3)-coated SrTiO(3) substrates by pulsed-laser deposition with different layer periodicity and layer thickness was characterized by means of transmission electron microscopy. Electron diffraction and contrast analysis revealed a very clear and well-separated layer sequence. The microstructures of PbZr(0.2)Ti(0.8)O(3)/PbZr(0.4)Ti(0.6)O(3) and PbZr(0.4)Ti(0.6)O(3)/PbZr(0.6)Ti(0.4)O(3) multilayers show a similar tendency in the dependence on the individual layer thickness. Whereas with thick individual layers, tetragonal a-domains are confined to specific layers of the two types of multilayers, below a certain critical thickness of the individual layers, a-domains extend over the whole film. This indicates a transition into a uniform tetragonal lattice and strain state of the whole multilayer. Increasing the layer periodicity further, the interfaces in PbZr(0.4)Ti(0.6)O(3)/PbZr(0.6)Ti(0.4)O(3) multilayers become rough, and complex a-domain configurations appear.