The early oxynitridation stages of hydrogen-terminated (100) silicon after exposure to N-2 : N2O. Nitrogen bonding states

Nitridation of hydrogen-terminated silicon in a diluted N2 : N2O atmosphere was studied by X-ray photoemission spectroscopy and high-resolution electron microscopy. Our analysis showed that the broad N(1s) peak of width 1.5 eV at 398-399 eV, usually reported in the literature, is preceded by the formation of a narrow peak of width around 1.0 eV at 397.5 eV, attributed to the moiety Si3N in which silicon is only marginally oxidized, and two other peaks at 400.0 eV and 401.5 eV, attributed to the moieties Si2NOSi and SiNO, respectively.