Preparation and Characterization of Multilayer Capacitor with SrTiO3 Thin Films by Aerosol Chemical Vapor Deposition

The deposition of crystalline and amorphous STO (SrTiO 3 ) 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 δ) 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 of 10 -8 –10 -6 A/cm 2 at up to ±30 V 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 °C, showing a capacitance density of higher than 900 nF/cm 2 (effective electrode area: 2 × 2 mm 2 ), a dielectric loss of 0.1% at 1 kHz and a leakage current of 10 -7 A/cm 2 at ±5 V DC .