AGING, ANNEALING, AND DIELECTRIC-PROPERTIES OF NEODYMIUM OXIDE THIN-FILMS

Thin film capacitors of AlNd2O3Al structure are fabricated by the resistive heating method under a vacuum of 2.66 × 10−3 Pa. The thicknesses of the dielectric films are measured by a multiple beam interferometer. Aging, annealing, and dielectric properties are studied in the frequency range 1 to 30 kHz at various temperatures (303 to 483 K). The capacitance, though dependent on frequency and temperature, is found to be almost constant at room temperature for all frequencies. The relative variations in the capacitance normalized at 10 kHz are characterized. The loss factor, showing a loss peak minimum, increases with the rise of temperature and tan δmin shifts to higher frequencies. The dielectric constant (5.66), the temperature coefficients of capacitance (646 ppm/K) and permittivity (623 ppm/K), and the linear expansion coefficient (23 ppm/K) are evaluted at 1 kHz and at room temperature. From the plot of frequency (tan δmin) versus inverse absolute temperature two activation energies are determined as 0.245 eV and 0.037 eV in the high (>400 K) and low (<400 K) temperature region, respectively. Copyright © 1990 WILEY‐VCH Verlag GmbH & Co. KGaA