Direct structural evidences of Mn dilution in Ge

X-ray diffraction, transmission electron microscopy, extended x-ray absorption fine structure spectroscopy, and x-ray photoemission spectroscopy have been used to study the structural properties of $MnxGe1−x$ ion implanted alloys $(x≃0.04)$ at 240 and $270°C$ substrate temperatures. Between 40% and 50% of the Mn atoms are found to occupy substitutional sites. No interstitial Mn atoms are found. The Mn–Ge coordination distance is $2.50(2)Å$⁠. Moreover, in the subsurface implanted layer [up to $32(2)nm$ depth] all the Mn atoms are effectively diluted in the Ge matrix, reaching a peak doping concentration of $7±1%$⁠.