Chemical fabrication SrBi4Ti4O15 thin films

The ferroelectric compound SrBi4Ti4O15 that belongs to the so-called Aurivi llius family could be promising for the fabrication of ferroelectric thin f ilm memories. Pure SrBi4Ti4O15 powders were obtained after hearing adequate sols (bismuth and strontium 2-ethylhexanoates in 2-ethylhexanoic acid and appropriate amount of titanium isopropoxide) at 350 degrees C for 12 h and subsequently putting the samples directly in an electric oven at 700-900 de grees C for 3 h. When spin-coated on silicon wafers and submitted to a simi lar process, the same sols always led to a mixture of SET and the pyrochlor e phase Bi2Ti2O7. In order to avoid the presence of this impurity, extra bi smuth content (0-40 mol%) was added during the preparation of the sols. The pyrochlore formation was completely eliminated when using 20% bismuth exce ss and the following process. (spin-coating 250 degrees C/5 min-750 degrees C/1 min)/10 times + final annealing at 800 degrees C/1 h (C) 1999 Elsevier Science Limited. All rights reserved.