Interdiffusion of magnesium and iron dopants in gallium nitride

The interdiffusion of magnesium and iron in gallium nitride (GaN), i.e., magnesium–iron interdiffusion, was investigated using magnesium-doped GaN layers on iron-doped GaN substrates. The investigation confirms that the magnesium–iron interdiffusion strongly depends on the concentrations of magnesium and iron, that is, it occurs when the iron and magnesium concentrations are high (magnesium: 2 × 1020 cm−3; iron: 2 × 1019 cm−3). It also confirms that diffused iron in the magnesium-doped GaN layer acts as a nonradiative recombination center in GaN.