Periodicity and orientation dependence of electrical properties of [(Pb0.90La0.10)Ti0.975O3/PbTiO3]n (n = 1-6) multilayer thin films

The [(Pb0.90La0.10)Ti0.975O3/PbTiO3]n (PLT/PT)n (n = 1-6) multilayer thin films were deposited on the PbOx(1 0 0)/Pt/Ti/SiO2/Si substrates by RF magnetron sputtering method. The layer thickness of PbTiO3 in one periodicity kept unchanged, and the layer thickness of (Pb0.90La0.10)Ti0.975O3 is varied. The electrical properties of the (PLT/PT)n multilayer thin films were investigated as a function of the periodicity (n) and the orientation. The studied results show that the PbOx buffer layer results in the (PLT/PT)n films' (1 0 0) orientation, and the (1 0 0)-oriented (PLT/PT)n multilayer thin films with n = 2 exhibit better pyroelectric properties and ferroelectric behavior than those of (PLT/PT)n films with other periodicities and orientations. The underlying physical mechanism for the enhanced electrical properties of (PLT/PT)n multilayer thin films was carefully discussed in terms of the periodicities and orientations.