Nanolayer BaTiO₃ thin film capacitors using magnetron sputtering

Abstract

Low leakage and high dielectric constant ferroelectric BaTiO3 thin film capacitors, taking advantage of the best properties of both amorphous and polycrystalline materials, were fabricated using radio frequency magnetron sputtering. The leakage current density was reduced to 10⁻¹⁰ A/cm² at a field intensity of (2 ± 0.5) × 10⁵ V/cm by using a nanolayer structure with an amorphous layer, on a number of alternating stacked layers of polycrystalline on microcrystalline material. This leakage current is believed to be the lowest reported so far for BaTiO3 with a dielectric thickness in the range of 250 nm. The dielectric constant and other electrical properties can be purposely controlled by choosing the number of layers and deposition conditions.

Keywords:

• BaTiO₃
• ferroelectrics
• high ε