Aerosol Deposition of Ba0.8SrolTiO3 Thin Films

摘要

In this work we optimized conditions for aerosol deposition of homogeneous, nano-grained, smooth Ba_(0.8)Sr_(0.2)TiO_3 thin films. Investigation involved optimization of depositionparameters, namely deposition time and temperature for different substrates. Solutions wereprepared from titanium isopropoxide, strontium acetate and barium acetate. Films weredeposited on Si (1 0 0) or Si covered by platinum (Pt (1 1 1) /Ti/SiO_2/Si). Investigationshowed that the best films were obtained at substrate temperature of 85℃. After depositionfilms were slowly heated up to 650℃, annealed for 30 min, and slowly cooled. Grain size ofBST films deposited on Si substrate were in the range 40-70 nm, depending on depositionconditions, while the same films deposited on Pt substrates showed mean grain size in therange 35-50 nm. Films deposited under optimal conditions were very homogeneous, crack-free, and smooth with rms roughness lower than 4 nm for both substrates.