Improved electrical properties of sputtering Pb_(1.10)(Zr_(0.52),Ti_(0.48))O_3/Pb_(1.25)(Zr_(0.52),Ti_(0.48))O_3 multilayer thin films

摘要

Multilayer PZT thin films composed of Pb_(1.10)(Zr_(0.52),Ti_(0.48))O_3 and Pb_(1.25)(Zr_(0.52,-)Ti_(0.48))O_3 films were deposited on Pt(111)/Ti/SiO_2/Si(100) substrate coated by Pb_(1.10)(Zr_(0.52),Ti_(0.48))O_3 buffer layer using RF magnetron sputtering. The effect of variation of layer numbers of Pb_(1.10)(Zr_(0.52),Ti_(0.48))O_3 and Pb_(1.25)(Zr_(0.52),-Ti_(0.48))O_3 thin films in multilayer PZT films was investigated. X-ray diffraction (XRD) analysis indicates all PZT films possess pure perovskite phase and (111) preferred orientation. For multilayer thin films, dense perovskite microstructures without obvious defects were observed using scanning electron microscope (SEM). Optimal dielectric properties with a ε_r of 1092 and a tanδ of 0.04 at 1 kHz were obtained in the PZT film with the maximum layer numbers (8-layer film, namely L-8). Well-saturated P-E was observed in L-8 film by a standard ferroelectric test system (P_r = 26.1 μC/cm~2, E_c = 60.1 kV/cm). Moreover, a Lower leakage current density (J = 5.49 × 10~(-6) A/cm~2 at 117 kV) was achieved in sample L-8.