[摘要]：High permittivity Bi24Fe2O39 (BFO) thin films have been deposited on platinized silicon substrates by a low temperature process combining rf magnetron sputtering at room temperature and postdeposition annealing at 450 degrees C. A nearly pure tetragonal crystal structure with highly (201)-preferred orientation, determined by x-ray diffraction, was formed in the BFO thin film. The BFO film not only exhibits high dielectric permittivity (epsilon(r)=113) and relatively low loss tangent (tan delta=0.012), but also shows a fairly small quadratic voltage coefficient of capacitance (alpha similar to 800 ppm/V-2) and a small temperature coefficient of capacitance (alpha(T) similar to 790 ppm/degrees C). Moreover, the leakage current density, obeying the Fowler-Nordheim tunneling mechanism, remains at a reasonably low level with the increase in applied electric field (J similar to 10(-6)-10(-4) A/cm(2) under E = 400 kV/cm). These attractive dielectric and electrical properties make the low temperature processed Bi24Fe2O39 thin film a promising candidate for high-k dielectric applications in silicon-based integrated circuits. (C) 2010 American Institute of Physics. [doi:10.1063/1.3524492]
