Orientation dependence of dielectric and ferroelectric properties of Pb(Zr0.8Ti0.2)O3∕Pb(Zr0.2Ti0.8)O3 multilayered thin films

Abstract

The Pb(Zr1−xTix)O3 multilayered films consisting of Pb(Zr0.8Ti0.2)O3 and Pb(Zr0.2Ti0.8)O3 layers with different orientations were deposited by radio frequency magnetron sputtering with PbOx and LaNiO3 (LNO) buffer layers. The PbOx and LNO buffer layers lead to the (001)∕(100) and (101)∕(110) orientations of the multilayered films, respectively. The orientation dependence of electrical properties of the multilayered films was investigated. Enhanced remnant polarization (2Pr=79.3μC∕cm2) and dielectric constant (εr=857) were obtained for the multilayered films with (001)∕(100) orientation as compared to those of the multilayered films with other orientations. These results reveal that the orientation control is important in obtaining good electrical properties.

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

“…All (PLT/PT) n multilayer thin films with a PbO x buffer layer possess highly (1 0 0) orientation, as indicated by the unusually high intensity of the (1 0 0) peaks. The buffer layer is introduced to reduce the lattice and thermal mismatch, and the underlying physical mechanism for the (1 0 0) orientation of the films was discussed elsewhere [15,16]. The (1 0 0) preferential orientation parameter (a 1 0 0 ) can be calculated by the formula (a hkl = I hkl / P I hkl ).…”

“…The PbO x buffer layer was in situ deposited on the Pt(1 1 1)/Ti/ SiO 2 /Si(1 0 0) substrates at 650 8C [15,16], and then (Pb 0.90 La 0.10 )-Ti 0.975 O 3 and PbTiO 3 ceramics targets were used to in situ prepare the (PLT/PT) n multilayer thin films layer by layer on the PbO x /Pt(1 1 1)/ Ti/SiO 2 /Si(1 0 0) substrates by RF magnetron sputtering at the substrate temperature of 600 8C, where (Pb 0.90 La 0.10 )Ti 0.975 O 3 and PbTiO 3 ceramics targets were prepared by a solid state reaction route using PbO, TiO 2 and La 2 O 3 . The layer thickness of PbTiO 3 phase in one periodicity kept unchanged ($100 nm), the layer thickness of (Pb 0.90 La 0.10 )Ti 0.975 O 3 phase in one periodicity is varied ($660 nm for n = 1, $280 nm for n = 2, $153 nm for n = 3, $90 nm for n = 4, $52 nm for n = 5, and $27 nm for n = 6) for keeping the same thickness of all films, and the thickness of all the multilayer films is the same ($760 nm).…”

“…The ferroelectric thin films can be applied in MEMS, sensors and actuators, and so on [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16]. It is well known that the interface coupling and the interactions among the layers in the multilayer structures can strongly affect the films' electrical properties, and an appropriate combination of the layers with different compositions can improve or create functional properties [4][5][6][7][8][9][10][11][12].…”

“…Electrical properties of ferroelectric thin films are strongly dependent on some factors, such as the composition [6,8], the orientation [7][8][9]15], and so on. Among these, the films' orientation is an important factor for improving electrical properties [7][8][9]15].…”

“…Among these, the films' orientation is an important factor for improving electrical properties [7][8][9]15]. In the past, we reported the orientation dependence of the electrical properties of the [Pb(Zr 0.8 Ti 0.2 )O 3 /Pb(Zr 0.2 Ti 0.8 )O 3 ] 5 multilayer thin films, and enhanced dielectric and ferroelectric properties were obtained in the multilayered structure [15]. So it is interesting and necessary to prepare the multilayer thin films with special orientation.…”