Method of calculating thickness of graphene layer and method of measuring content of silicon carbide by using XPS

A method of measuring a content of silicon carbide included in an interface layer between a silicon substrate and a graphene layer directly grown on the silicon substrate, the method comprising:

• emitting X-ray radiation, using an X-ray photoelectron spectroscopy (XPS) instrument, toward the silicon substrate using a source on the XPS instrument;
• obtaining a spectrum of a photoelectron beam emitted from the silicon substrate in response to emitting the X-ray radiation toward the silicon substrate using a sensor on the XPS instrument;
• and
• measuring a ratio of the content of silicon carbide relative to the content of the interface layer by using the spectrum of the photoelectron beam emitted from the silicon substrate by using X-ray photoelectron spectroscopy.