Detection and Characterization of Single Near-Interface Oxide Traps with the Charge Pumping Method

We carried out detection and characterization of single Si/SiO₂ near-interface oxide-traps (NIOTs) using the systematic measurements procedure by the high-resolution charge pumping (CP) method we developed, and we found a single NIOT where CP current depends upon both fall and rise times of the CP gate pulse. This demonstrates that individual Si/SiO₂ NIOTs have two energy levels, one in the upper part, the other in the lower part of the silicon bandgap. The results may suggest that the NIOTs also have an amphoteric nature, i.e., have both donor-like one-electron, and acceptor-like two-electrons states, similar to the Si/SiO₂ interface traps.