Hydrogen redistribution in CVD SiO2 during post-oxidation annealing investigated by SIMS

The applicability of secondary ion mass spectrometry (SIMS) was evaluated for measuring the variation of hydrogen distributions in chemical vapor deposition (CVD) SiO2 films by post-oxidation annealing (POA). No noticeable hydrogen migration induced by electron or ion beam irradiation was observed. An increase of hydrogen ion intensity at the thermal SiO2/Si interface was observed regardless of the presence of a CVD SiO2 cap. Also, it was found that POA caused remarkable reduction of the hydrogen concentration at the SiO2/Si interface. This result agreed well with those by grazing incidence X-ray reflectivity (GIXR) and C–V measurements. These results lead us to the conclusion that the excess hydrogen present at the interfacial region was released during re-oxidation. # 2004 Elsevier B.V. All rights reserved.