Ion-photon emission from titanium target under ion beam sputtering

Ion photon emission in the wavelength range of 280 - 420 nm resulting from 5 Kr+ ion beam sputtering from titanium in the presence and the absence of oxygen was studied experimentally. The observed spectra consist of a series of discrete lines superimposed with a broadband continuum. Discrete lines are attributed to excited neutral Ti I and excited ions Ti II. The differences in the observed intensities of spectral lines are discussed in terms of the electron-transfer processes between the excited sputtered atom and electronic levels of the solid. The radiative dissociation process and breaking of chemical bonds seem to contribute to the enhancement of emitted photons intensity. Continuum radiation was observed and is very probably related to the electronic structure of titanium. The collective deactivation of 3d-shell electrons appears to play a role in the emission of this radiation.