Transition of dominant lattice sites of Mg in InN:Mg revealed by Raman scattering

The behavior of Mg dopants in InN films grown by molecular beam epitaxy was studied by Raman scattering in a wide Mg concentration ([Mg]) range from 1 × 1016 to 4 × 1021 cm−3. Transition of dominant lattice sites of Mg dopants was investigated through a diffusion-collision model based on Mg-related local vibrational modes, which was further confirmed through stress analysis. It was found that Mgi and MgIn-N-Ini are the dominant sites of Mg dopants at [Mg] < 1.8 × 1020 cm−3, while the complex of MgIn-N-Mgi dominates with further increasing [Mg]. This study provides an insight on the behavior of Mg and would be helpful for achieving effective p-type doping in InN.