Prediction of dielectric reliability from I-V characteristics: Poole-Frenkel conduction mechanism leading to √E model for silicon nitride MIM capacitor

摘要

Two assumptions lead to a correlation between the leakage mechanism of a dielectric and dielectric reliability: the degradation of the dielectric is a direct cause of the leakage current flowing through the dielectric and breakdown occurs after a critical charge has been forced through the dielectric. The field and temperature dependence of the leakage current mechanism then determine the voltage acceleration factor and the activation energy of TDDB experiments. This simple physical model describes the reliability of metal insulator metal (MIM) capacitors with PECVD SiN remarkably well. The current conduction mechanism is described by Poole-Frenkel theory, leading to a √E dependence of the time to breakdown on the applied electric field. The model predicts correctly the voltage acceleration factor and its temperature dependence and the activation energy.