Heavy ion irradiation effects on capacitors with SiO2 and ONO as dielectrics

We study heavy ion irradiation effects on capacitors with the structure of a Floating Gate Flash cell. We demonstrate that the modifications of the capacitors electrical characteristics observed after irradiation depend on the physical position of the defects produced by ions into the dielectric. In particular, we focus our attention on the leakage current produced by ion irradiation. We evidence that SiO₂ capacitors feature a leakage current higher than that observed in capacitors with an Oxide-Nitride-Oxide (ONO) stack as dielectric. Finally, we investigate the behavior in time of the leakage produced by ions.