Preparation and characterization of multilayer capacitor with SrTiO3 thin films by aerosol chemical vapor deposition

The deposition of crystalline and amorphous STO (SrTiO3) thin films by aerosol chemical vapor deposition (ASCVD) was investigated. The crystalline STO thin film exhibited a higher dielectric constant of approximately 160 and a dielectric loss (tan delta) of 3.5% (at 1 kHz). In contrast, the amorphous, STO thin films with dielectric constants of 20-65 showed a smaller dielectric loss below 1 % and much lower leakage currents 10(-8)-10(-6) A/cm(2) at up to +/- 30V(DC). On the basis of these results, a thin-film multilayer ceramic capacitor (MLCC) with ten amorphous STO dielectric layers and Pt electrodes of 160 and 120 nm thicknesses, respectively, was prepared at a processing temperature of 600 degrees C, showing a capacitance density of higher than 900 nF/cm(2) (effective electrode area: 2 x 2 mm(2)), a dielectric loss of 0.1% at 1 kHz and a leakage current of 10(-7) A/cm(2) at +/- 5V(DC).