Paraelectric (Ba0.6Sr0.4)TiO3 thick films by direct-write

MicroPen (TM) direct-write technique has been used to fabricate polycrystalline paraelectric BST 60/40 11-140 mu m thick films on alumina substrates. The dielectric properties of the thick films were studied as a function of film thickness, microstructure, and the state of residual stresses. Sin(2)psi X-ray analyses indicated a compressive state of stress in the films which decreased from similar to 40 MPa at 36 mu m to similar to 15 MPa at 140 mu m. The cubic -> tetragonal transition temperature was found to be -10 degrees C. No thickness dependence of the transition temperature was observed. Field induced polarization curves also indicate no apparent nonlinear behavior up to 4 kV/mm.