Fabrication and structural properties of sol-gel derived SBN films

Structural changes in sol-gel derived Sr0.6Ba0.4 Nb2O6 (SBN) films have bee n studied as functions of annealing temperature, annealing atmosphere, and film thickness. The tetragonal tungsten bronze (TTB) structure SBN was obta ined at annealing temperatures above 700 degrees C. Post-annealing in air, oxygen, or argon ambient showed no apparent different effects on the struct ural proper ties of the films. Preferred and better oriented (001) SBN laye rs, however, were found to improve with film thickness. Enlarged grain size and a much reduced surface roughness have also been observed in thicker fi lms. In the present studies, we have fabricated crack-free SBN films of up to 2.3 mu m thick with good mean crystallinity. (C) 1999 Elsevier Science L imited All rights reserved.