Survival of the excited Mg atoms sputtered from Mg, MgO, MgF2 and oxygen-covered Mg surface

The intensities of optical spectral lines emitted from the sputtered excited Mg atoms were measured for 1–10 keV Ar+ impact on polycrystalline Mg, MgO and MgF2 targets. Survival coefficients for the excited Mg atoms in the 3p3P1, 3p1P1and 4s3S1 states formed during sputtering of three different targets were calculated for the first time. It was found that the survival coefficient depends on the type of the target, that is, it decreases in the order of Mg–MgO–MgF2. Next, the survival coefficient of an excited atom sputtered from a Mg surface were determined as a function of the surface oxygen coverage. The survival coefficient was found to decrease with oxygen coverage of the surface and get saturated at surface oxygen coverage of θ ∼ 0.91. It is shown that the influence of target matrix and surface oxygen coverage on the optical emission from sputtered atoms can be well explained by the electron-tunneling model.