Shallow electron traps in high-k insulating oxides

In the present work the use of low temperature (77 K) charge injection and thermally activated emission is proposed as a universal method for characterization of shallow traps in high permittivity insulating oxides (HfO2, ZrO2, LaSiOx). A broad temperature range (77 K-300 K) allows one to evaluate density and energy distribution of electron traps within the energy depth range approximate to 1 eV below the oxide conduction band. The volume concentration of these traps is found to be in the range of 1019-1020 cm-3 in all studied materials indicating that shallow trapping will significantly affect performance of the high-k oxide-based devices operating at low temperature and/or very short pulse times.

Automated summary

The study suggests using low temperature charge injection and thermally activated emission as a universal method for characterization of shallow traps in high permittivity insulating oxides. The volume concentration of these traps in all studied materials is found to be in the range of 1019-1020 cm-3, indicating that shallow trapping will significantly impact the performance of devices operating at low temperature and/or very short pulse times.