Polycrystalline(1−x)Ta2O5–xAl2O3thin films were fabricated by metalorganic solution deposition technique on Pt-coated Si substrate at a temperature of 750 °C. Thin films with0.9Ta2O5–0.1Al2O3composition exhibited improved dielectric and insulating properties compared toTa2O5thin films. The measured small signal dielectric constant and dissipation factor at 100 kHz were 42.8 and 0.005, respectively. The temperature coefficient of capacitance was 20 ppm/°C in the measured temperature range of 25–125 °C. The leakage current density was lower than6×10−8 A/cm2up to an applied electric field of 1 MV/cm. A charge storage density of18.9 fC/&mgr;m2was obtained at an applied electric field of 0.5 MV/cm. The high dielectric constant, low dielectric loss, low leakage current density, and good temperature and bias stability suggest(1−x)Ta2O5–xAl2O3thin films to be a suitable dielectric layer in integrated electronic devices in place of conventional dielectrics such asSiO2orSi3N4.©1997 American Institute of Physics.