Singly ionized magnesium–oxygen complex impurities in silicon

Previous study indicates, that magnesium, when diffused into silicon, can pair with dispersed oxygen in the crystal to form magnesium–oxygen complex impurities. Recently, we have successfully introduced magnesium into silicon containing oxygen as well as group-III impurities. We have observed for the first time the excitation spectrum of singly ionized magnesium–oxygen complex impurities, which clearly demonstrates that magnesium–oxygen complex impurity is a double donor in silicon. Our experimental result also shows that the ionization energy of singly ionized magnesium–oxygen donor is 274.90 meV, which is slightly larger compared with that of singly ionized magnesium donor in silicon.