Effect of oxygen on the growth of epitaxial ErSi2−x films on Si by the reactive deposition technique

Epitaxial ErSi2−x have been grown by reactive deposition epitaxy technique on 〈111〉Si substrate in a high vacuum system (operating pressure ∼ 10−8 Torr) at different substrate temperature. The residual gas pressure during deposition was controlled by a mass spectrometer and the O partial pressure was varied in the range 1 × 10−9–4 × 10−8 Torr. Rutherford backscattering spectrometry in combination with channeling effect, nuclear reaction analysis 16O(d, p)17O and transmission electron microscopy have been used to independently determine the O and Er concentration and the crystalline quality of the layer. The correlation between the O concentration in the silicide and the deposition parameter has been determined. Good quality epitaxial layers were been obtained only if O was incorporated in the silicide at a concentration of about 7 at%.