Analysis of anodic oxidation influence on leakage current and MIS model parameters of Ta and NbO capacitors was performed. Electron transport depends on potential barriers and density of donors and traps in an insulating layer and interfaces. In this case leakage current value depends on anodic oxidation parameters. The VA characteristics in normal and reverse mode of NbO and Ta capacitors were analyzed to show relation between anodic oxidation and MIS model parameters as barrier height and density of localized states in insulating layer. Some electron transport processes are reversible like ohmic and Poole-Frenkel mechanism and then they do not decrease reliability. Capacitor reliability is determined by irreversible processes like microcrystal creations, cracks in insulating layer etc. Leakage current stability during life tests vs. anodization temperature at constant current density was performed and it shows that there are correlations between anodization condition like current density, electrolyte composition, temperature and capacitor parameters stability and reliability.
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