Tunneling of X-ray photons through a thin film under total internal reflection conditions

Tunneling of 0.154-and 0.139-nm x-ray photons through a thin film under total internal reflection conditions has been experimentally demonstrated. The NiSi2 film 13 nm thick is deposited by magnetron sputtering on a polished Si substrate. A beam with an angular spread of 20″ is directed to the Si/NiSi2 interface from the inside through the lateral surface of a sample. A peak associated with tunneling of photons from Si to air through the NiSi2 film is observed at grazing angles of θ1 > 0.4θc, where θc is the critical angle of total internal reflection at the Si/NiSi2 interface. The integral intensity of tunneling peaks that is measured for various θ1 angles agrees with the calculations.