Auger electron spectroscopy and Rutherford backscattering-channeling studyof silicon nitride formation by low energy N-2(+) ion implantation

Direct nitridation of Si (100) surface by low energy N-2(+) ion beam implan tation at room temperature for different ion doses and angles of incidence has been investigated by in-situ Auger electron spectroscopy and glancing R utherford backscattering-channeling (RBS-C) measurements. The results show that with increase of N-2(+) ion dose the N concentration in the Si surface increases and reaches to a surface stoichiometry close to that of Si3N4. T he saturation dose and the thickness of the silicon nitride layer are relat ed to the N-2(+) ion energy Complete nitride layer can be formed at inciden t angles of 0 degrees-30 degrees. At larger angles the degree of nitridatio n decreases and no nitride layer could be found at incident angles larger t han 54 degrees. The RBS-C results also suggest that a heavy damaged layer b eneath the surface nitride layer can be formed due to ion beam implantation .