Characterization of channel hot electron injection by the subthreshold slope of NROM/sup TM/ device

Channel hot electron (CHE) injection, is widely used as main programming method in flash products. The spatial distribution could only be measured indirectly through stress-based experiments. A simple measurement technique to spatially characterize CHE injection is presented. It is shown that subthreshold slope degradation during programming of NROM/sup TM/ device provides the location and distribution of the injected electrons. It is shown that injection takes place mostly above the drain region and thus, results in subthreshold slope degradation. It is further shown, based on two-dimensional modeling, that charge distribution width is narrower than 40 nm.