ELECTRON BEAM-ASSISTED GROWTH OF ULTRATHIN SILICON OXYNITRIDE FILMS ON SI(100) AT MODERATE TEMPERATURES - IN-SITU DETERMINATION OF COMPOSITION AND GAP WIDTH

Exposure of a Si(100)-2x1 surface to low pure NO gas pressures (less t han or equal to 8x10(-6) mbar) at moderate temperatures (room temperat ure (RT) - 600 degrees C) leads to the formation of an amorphous passi vating oxynitride layer (thickness similar to 0.5 nm). However, we sho w that low energy (100 eV) electron bombardment of the surface, during exposure to NO, induces the formation of amorphous ultrathin (less th an or equal to 2 nm) silicon oxynitride films having different element al compositions. At RT, oxygen-rich films were grown, while nitrogen-r ich layers were formed at 600 degrees C. The thickness and the composi tion or the gap of the resulting insulating layers have been in situ d educed from Auger Electron Spectroscopy (AES) or Reflection Electron E nergy Loss Spectroscopy (REELS) measurements respectively, using a sta ndard single-pass Cylindrical Mirror Analyzer (CMA).