Orientation control and ferroelectric properties of (Pb_(0.90)La_(0.10))Ti_(0.975)O_3 thin films prepared by rf magnetron sputtering with a LaNiO_3 buffer layer

摘要

Highly (110)- and (l00)-oriented (Pb_(0.90)La_(0.10))Ti_(0.975)O_3 (PLT) thin films were deposited on Pt(111)/Ti/ SiO_2/Si(100) and SiO_2/Si(100) substrates by rf magnetron sputtering with a LaNiO_3 (LNO) buffer layer. The LNO buffer layer plays an important role in the orientation and ferroelectric properties of the PLT thin films. Highly (100)-oriented PLT thin films deposited on the LNO/SiO_2/Si(100) substrates are obtained at a low processing temperature of 500 ℃. The ferroelectric properties of the PLT thin films with different orientations are discussed. Highly (100)-oriented PLT thin films possess better ferroelectric properties, with higher remnant polarization (2P_r = 40.4 μC/cm~2) and lower coercive field (2E_c = 201 kV/cm) than that of (110)-oriented PLT thin films (2P_r = 22.4 μC/cm~2, 2E_c = 246 kV/cm). The enhanced ferroelectric property is attributed to the different orientations of the PLT thin films.