Multilayer La-modified PbTiO3 capacitors via RF magnetron sputtering

Abstract

In this study, multilayer ceramics (MLCs) composed of La-modified PbTiO3 layers with internal Pt electrodes were fabricated by radio frequency (RF) magnetron sputtering. Multiple (Pb0.9,La0.1)Ti0.975O3 (PLT) layers with thicknesses of approximately 500 nm were deposited on Pt/Ti-coated Si substrates through a square movable shadow mask. The isolated internal Pt electrodes were prepared by sliding the movable shadow mask. The MLCs composed of one, three, and five PLT layers were fabricated by alternate sputtering deposition of Pt electrodes and PLT ferroelectric layers with the movable shadow mask. The MLCs had a smooth and crack-free surface, and dense PLT layers could be prepared between the internal Pt electrodes. The MLCs exhibited excellent dielectric properties and their capacitances increased with the number of PLT layers, while the dielectric losses were lower than 3.5 %. The P–E hysteresis loops of MLCs showed symmetric loops because of the alternating direction of external electric field on the ferroelectric PLT layers.