New insight into tantalum pentoxide Metal-Insulator-Metal (MIM) capacitors: Leakage current modeling, self-heating, reliability assessment and industrial applications

In this study, conduction asymmetry is analyzed using asymmetric stacks in order to appreciate the cathode role. Then original test structures are used to highlight fringe leakage and to model asymmetry in a pure Ta
₂
O
₅
capacitor for both surface and peripheral currents. Finally, the impact of peripheral on self-heating and consequently on reliability parameters is deeply investigated. Important information are then provided regarding intrinsic MIM characteristics, process optimization, reliability methodology and design rules.