Nitridation of HfSiO films improves certain physical and electrical properties-when using gate stack layers-such as their crystallization temperature and their resistance to interdiffusion. We have studied the band alignment of HfSiO and HfSiON films by soft x-ray photoemission, oxygen K -edge x-ray absorption, and spectroscopic ellipsometry. Nitridation of HfSiO reduced the band gap by 1.50 eV±0.05 eV, and the valence- and conduction-band offsets by 1.2 eV±0.1 eV and 0.33 eV±0.05 eV, respectively. Although the band-gap reduction should lead to increased leakage, the barrier heights are still sufficient for proposed near-future complementary metal-oxide-semiconductor applications.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)