The effect of Mg doping on GaN nanowires

We present a comparison between the structural, chemical, and electrical properties of Mg-doped GaN nanowires grown by hot-wall chemical vapour deposition using two different Mg sources, namely, metallo-organic bis(methylcyclopentadienyl) magnesium and magnesium nitride powder. We find that Mg from the solid nitride source is more effectively incorporated into the nanowires while better maintaining the nanowire integrity. After Mg activation, the nanowires are partially or fully compensated. In comparison, vapour phase doping results in an obvious degradation of the nanowire morphology in spite of lower Mg incorporation levels.