The effect of ion implantation in the microstructure of Si3N4 films: An X-ray absorption study

The effect of ion implantation in the microstructure of thin Si3N4 films is studied with Extended X-ray Absorption Fine Structure (EXAFS) and Near-Edge X-ray Absorption Fine Structure (NEXAFS) measurements at the N-K-edge. The stoichiometric Si3N4 films were subjected to implantation with Ar+ or N-2(+) ions, at 77 and 300 K. Analysis of the NEXAFS spectra indicates that ion implantation creates N-dangling bonds which introduce a characteristic resonance line (RL) and a redshift of the absorption edge, both of which depend on the projectile and the substrate temperature during implantation. Finally, the EXAFS data demonstrate that implantation modifies the microstructure down to the nearest-neighbor shell, as that is indicated by the reduction of the coordination number from 3 to 2.