SrTa2O6 (STA) is a promising high-dielectric-constant (epsilon) material. In this study, STA thin films were fabricated using the sol-gel method. The capacitance-voltage and leakage-current characteristics of crystalline and amorphous STA thin-film capacitors were investigated. STA thin films crystallized at an annealing temperature of 800 degrees C Crystalline STA thin films exhibited a high epsilon of about 110, whereas amorphous STA thin films showed a much lower epsilon of about 26-41. However, amorphous STA thin films had a much more constant capacitance as a function of voltage. Of the amorphous thin films, the one annealed at 700 degrees C had the highest epsilon of about 41, the lowest leakage current of 10(-8) A/cm(2), and a very constant capacitance as a function of voltage with a quadratic voltage-capacitance coefficient (alpha) of 27 ppm/V-2. The crystalline STA thin film had a negative alpha that was independent of frequency, which suggests that dipolar relaxation occurs and is responsible for the large change in the capacitance. The amorphous thin films had a positive a that decreased with increasing frequency, which implies that electrode polarization occurs. (c) 2012 Elsevier B.V. All rights reserved.