Electronic structures of N2+ and O2+ ion‐implanted Si(100)

Abstract

AbstractElectronic structures of N2+ and O2+ ion‐implanted Si(100) (SiNx, SiOx) have been investigated by means of x‐ray photoelectron spectroscopy (XPS), x‐ray‐induced Auger electron spectroscopy (XAES) and x‐ray absorption near‐edge structures (XANES). For the O2+ ion irradiation, the binding energies of Si 2p and SiKLL Auger lines for SiOx at x > 0.4 show that SiO2 is predominantly produced. The XANES spectra of SiOx (x > 0.2) at the Si 2p edge are similar to those of bulk SiO2. However, other oxides such as SiO are scarcely observed in these spectra. These observations indicate that the SiOx layer consists of a mixture of Si and SiO2 islands. On the other hand, chemical shift of the Si 2p and SiKLL Auger lines for SiNx becomes larger gradually with the implantation. Thus, it is considered that such changes are due to the stepwise replacement of the SiSi bond with the SiN bond. It implies that SiNx has several chemical states of nitride.