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

The [(Pb_0.90La_0.10)Ti_0.975O₃/PbTiO₃]_n (PLT/PT)_n (n = 1-6) multilayer thin films were deposited on the PbO_x(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 (Pb_0.90La_0.10)Ti_0.975O₃ 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 PbO_x 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.