On the meaning of charge pumping curve edges

This paper discusses and clarifies the origin of two-level charge pumping (CP) curve edges and edges asymmetry in the case of conventional MOSFETs: in a large lower part of these edges the CP current is controlled by one of the two Fermi levels at the interface and by the associated contribution of interface traps in both halves of the silicon bandgap. Edges steepness and asymmetry thus result from the dependence with gate bias of the corresponding surface potential. This allows the Si-SiO₂ interface trap density to be extracted from the slope of these edges. These results are discussed with regard to the other ways these edges have been interpreted.