Niobium as new material for electrolyte capacitors with nanoscale dielectric oxide layers

New niobium electrolyte capacitors were produced on the base of newly developed capacitorgrade niobium metal powder. To gain a comprehensive understanding of the reactions taking place during the fabrication process which comprises several anodic oxidation and thermal treatment steps, the influence of heat treatments on the electrical and structural properties of the nanoscale dielectric niobium pentoxide layers was investigated. Capacitance measurements at fixed frequency were used to examine the electrical properties of the dielectric oxide layers directly after oxidation steps and heat treatments. Thermogravimetric analysis was applied to characterize the behavior of oxidized niobium anodes during the thermal annealing processes. Scanning electron and high-resolution transmission electron microscopy was performed in order to determine the thickness and microstructure of the nanoscale dielectric niobium pentoxide layers. In the following, the first results of these characterizations will be presented.