Tantalum capacitors are polarized capacitors with capacitances
between 100 nF and several thousand microfarads (µF). Tantalum capacitors consist of a metallic anode body embedded in plastic. The dielectric is made of tantalum pentoxide (Ta2O5), which is oxidized in a thin layer on the porous anode and is characterized by a high dielectric strength. This is over 600 V/µm. The dielectric has a permittivity
between 20 and 30 and can be applied in minimal thicknesses of only 10 nm. Due to its open-pored surface structure, the anode forms a large area on which an oxide layer only a few hundred nanometers thick is deposited. Therefore, relatively large capacitances can be realized with tantalum capacitors.