SrBi2Nb2O9 ferroelectric powders and thin films prepared by sol-gel

Pure SrBi2Nb2O9 powders and thin films were obtained using sol-gel synthesi s from mixtures of niobium ethoxide, bismuth and strontium 2-ethylhexanoate s. Powders crystallized for 2 hours at 700 degrees C had grain sizes of abo ut 100-150 nm. SrBi2Nb2O9 thin films were prepared by spin-coating a stable precursor solution onto Si/SiO2/TiO2/Pt substrates. Crystallization of pur e SrBi2Nb2O9 phase occurred at about 500-550 degrees C. Randomly oriented 0 .3 mu m-thick crack-free films were obtained after 10 successive deposition s and heating at 700 degrees C for 2 hours. P-E hysteresis loops have confi rmed the ferroelectric behavior of the films: they show a remanent polariza tion of 2.5 mu C/cm(2) (5 V, 8 ms). No fatigue was observed up to 10(9) ful l switchings.