Damage profiling of Ar⁺ sputtered Si(100) surface by medium energy ion scattering spectroscopy

To study the damage profile development due to ion bombardment as a function of the ion dose and the ion incidence angle effect on the damage profiles, MEIS spectra were taken from a clean Si surface and ion beam sputtered Si surfaces. MEIS analysis shows that the surface layer becomes amorphous initially and the amorphous surface layer gets thicker for a Si(100) surface bombarded with 3 keV Ar⁺ ions. The damage profile of the Si(100) saturated at the ion dose of 3 × 10¹⁶ ion/cm² at the incidence angle of 35° from the surface normal. At the saturation ion dose, the depth of the damaged layer was 9.6 nm. The depth of the damaged layer was significantly reduced from 14.2 nm at the surface normal to 4.8 nm at the incidence angle of 80°. Though the depth of the damaged layer was minimized for the sputtering at the extremely glancing angle of 80°, the damaged layer did not disappear but remained as a very shallow surface layer. These observations were reproduce by computer simulations by the Marlowe code qualitatively.