Ionic current study in thermally grown silicon dioxide films on polycrystalline silicon

Abstract

The ionic currents in thermally grown silicon dioxide films (PSD) between polysilicon (PS) are investigated by thermally stimulated polarization (TSPC) and depolarization (TSDC) currents and triangular voltage sweep (TVS) techniques. A mixture of dry oxygen and HCl (0, 4, 6, and 8 vol%) is used for oxidation. It is found that the ionic charge is situated near both the PS–PSD interfaces on ionic traps. The influence of electric field strength, oxidation time, and oxidation atmosphere is established. The results are discussed using the PS–PSD interface roughness model.