Abstract
Chemical states of so-called silicon monoxide, powder and evaporated films, were studied by fluorescent X-ray spectroscopy(FXS), X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy(AES). Si Kα and Kβ spectra show the existence of small amounts of SiOx(0<x<2) in addition to the main Si-SiO2 structure. Although in the AES measurement, SiOx could not be found, the XPS results showed the clear evidence of SiOx. The silicon monoxide has, based on these measurements, Si and SiO2 mainly and small amounts of SiOx.