Effects of thickness on the microstructure and energy-storage performance of PLZT antiferroelectric thick films

Abstract

The typical antiferroelectric (AFE) thick films Pb 0.94 La 0.04( Zr 0.98 Ti 0.02) O 3 (PLZT 4/98/2) with different thicknesses of 2, 4, 6 and 10 μm were successfully deposited on Pt (111)/ TiO 2/ SiO 2/ Si (100) substrates from polyvinylpyrrolidone (PVP)-modified chemical solution. The effects of thickness on the crystalline structure, electrical properties and the energy-storage performance were investigated in detail. X-Ray diffraction analysis and scanning electron microscopy pictures indicated that AFE films with a thickness less than 4 μm showed a (111)-preferred orientation with uniform surface microstructure. The electrical measurement results illustrated that, as the thickness increased, the saturation polarization, remnant polarization, dielectric constant and leakage current of AFE thick films were enhanced gradually, while the capacitive density and the critical breakdown fields were decreased. Moreover, all the PLZT 4/98/2 AFE films shared the same Curie temperature of about 224°C. As a result, the AFE thick films showed good energy-storage stability in a wide temperature range. The maximum energy-storage density of 47.4 J/cm3 was obtained in the 2-μm-thick PLZT 4/98/2 films measured at 3699 kV/cm.