High-field electron trapping in SiO₂

When linear voltage ramps were applied to MOS capacitors, the current-vs-voltage (I-V) curves indicated a region of quasisaturation of current, i.e., a ledge in the I-V characteristic. These ledges could be explained by an electron-trapping model. Trap cross sections and concentrations were dependent on sample processing and oxide thickness and were in the 10 -19 cm2 and 1012 cm-2 ranges, respectively. Comparison of shifts in the I-V and C-V curves showed that trapped charge to be within about 10 Å of the Si-SiO2 interface.