Jfm. Cillessen et al., THICKNESS DEPENDENCE OF THE SWITCHING VOLTAGE IN ALL-OXIDE FERROELECTRIC THIN-FILM CAPACITORS PREPARED BY PULSED-LASER DEPOSITION, Journal of applied physics, 81(6), 1997, pp. 2777-2783
Thin-film ferroelectric capacitors consisting of PbZr0.53Ti0.47O3 sand
wiched between La0.5Sr0.5CoO3 electrodes have been deposited using pul
sed laser deposition. The combination of oxidic perovskite-type materi
als results in capacitors with a coercive field (E(c)) which is compar
able with values for bulk ceramics. Textured thin-film capacitors with
;a columnar microstructure show lower switching voltages than epitaxia
l films. No thickness dependence of E(c) and a good endurance up to 10
(11) cycles have been observed for epitaxial as well as textured capac
itors with oxidic electrodes. In contrast, capacitors with a metallic
top electrode show an increase of E(c) with decreasing thickness of th
e ferroelectric layer. We show that charge injection can explain the e
xperimentally observed increase of E(c) with decreasing ferroelectric
layer thickness. An overview is given of the growth conditions needed
for PbZr0.53Ti0.47O3 films, because the precise stoichiometry is-of th
e utmost importance for the capacitor quality. (C) 1997 American Insti
tute of Physics.