Stress induced leakage current analysis via quantum yield experiments

This paper investigates the physical characteristics of stress induced leakage current (SILC) by means of quantum yield (QY) measurements and simulations. QY experiments allow us to infer the energy of tunneling electrons, which is an important factor for the damage generation process. The energy of SILC electrons is analyzed in three different types of p-MOSFET devices: n(+) gate surface channel and buried channel, and p(+) gate surface channel. We show that an extra tunneling current component due to native traps can be present even in virgin devices and it is elastic. Then it is shown that SILC electrons have less energy than direct tunneling electrons. This energy loss is then extracted from experimental data and the limitations of this extraction technique are addressed. Finally, experiments on p(+) gate p-MOSFET clearly demonstrate that electrons tunneling through traps created by electrical stress lose energy irrespective of their initial band. It is then concluded that native and stress induced traps have different physical characteristics.