Constant-current time dependent dielectric breakdown in thick amorphous SiO2 capacitors

Charge transport in thick amorphous silicon dioxide capacitors for integrated galvanic insulators is experimentally investigated and analyzed through numerical simulations carried out with a commercial TCAD tool. The material intrinsic defectivity and the large biases applied to such devices give rise to a leakage current which is responsible of degradation and failure. Hence it is crucial to have a complete understanding of the charge-transport main physical mechanisms in amorphous silicon oxide. For this reason, constant-current time dependent dielectric breakdown measurements have been performed on thick metal-insulator-metal structures and, in order to gain insight on the role of defects on breakdown, numerical simulations have been compared to experiments.