Analysis of Electronic Structures of Ion-Implanted SiOx and SiNx by Surface XANES.

Abstract

X-ray absorption near edge structure (XANES) has been applied to the elucidation of electronic structures in conduction-band region of SiOx and SiNx produced by ion implantation in Si (100). The XANES spectra of SiOx at the Si2p edge are similar to those of SiO2 but the spectral structure of intermidiate compound such as SiO is not observed. This fact suggests that the SiOx layer consists of a mixture of Si and SiO2 islands, and the conduction band of SiOx is mainly composed of the orbitals of SiO2. On the other hand, the XANES spectra at the Si2p edge of SiNx gradually change depending on the x-values, and a sharp resonance corresponding to the N-dangling appears at the N1s edge for x>1.0. These observations suggest that SiNx phase prefer randombonding structure rather than a mixture of Si and Si3N4 islands.