Enhanced Electrical Activation in In-Implanted Si0.35Ge0.65 by C Co-Doping

In this report, we have achieved a significant increase in the electrically active dopant fraction in Indium (In)-implanted Si0.35Ge0.65, by co-doping with the isovalent element Carbon (C). Electrical measurements have been correlated with X-ray absorption spectroscopy to determine the electrical properties and the In atom lattice location. With C + In co-doping, the solid solubility of In in Si0.35Ge0.65 was at least tripled from between 0.02 and 0.06 at% to between 0.2 and 0.6 at% as a result of C–In pair formation, which suppressed In metal precipitation. A dramatic improvement of electrical properties was thus attained in the co-doped samples