Stress-induced leakage current in ultrathin SiO2 layers and the hydrogen dispersive transport model

Abstract

The time dependence of the current density variation ΔJ(t) observed during constant gate voltage stress of metal–oxide–semiconductor capacitors with ultrathin gate oxide and oxynitride layers is investigated. The generation of bulk neutral defects in the SiO2 layer is calculated within a dispersive transport model, assuming that these defects are induced by the random hopping of H+ ions in the gate oxide layer. It is shown that the stress–voltage and gate-oxide-thickness dependence of ΔJ(t) can be quite well explained by this dispersive hydrogen transport model.