Processing and dielectric properties of sol-gel derived PMN-PT (68:32) thin films

PMN-PT thin films near MPB were prepared using sol-gel technique. A transparent solution of the ceramic was prepared by using lead acetate trihydrate, magnesium ethoxide, niobium ethoxide and titanium isopropoxide as precursors along with 2methoxyethanol as solvent and acetic acid as catalyst. Thin films of the ceramic were prepared on Pt/Si and on ITO coated glass substrates. X-ray diffraction (XRD) studies show the formation of perovskite phase of the films with less than (5%) pyrochlore phase. Scanning electron microscopy (SEM) study of the films on different substrates show well developed grains of sub-micron size. Dielectric constant measurement at different temperature was carried out. Room temperature value of dielectric constant and dielectric loss at 1 kHz of the ceramic thin films on ITO coated glass and Pt/Si substrates were found to be 500, 0.03 and 415, 0.01 respectively. Dielectric measurements for different thicknesses of the films have also been carried out. P-E loop and I-V studies of the films were also carried out.