Luminescence of Acceptors in Mg-Doped GaN

Luminescence of Acceptors in Mg-Doped GaN

What determines the emission peak energy of the blue luminescence in highly Mg-doped p-GaN?

We report a study of the 2.8 eV blue luminescence ~BL! in heavily Mg-doped p-GaN via resonant excitation with a tunable blue dye laser. The dependence of the BL on the excitation photon energy (Eex) is unlike that of the yellow luminescence found in n-type GaN. An Urbach-type band tail, with Urbach parameter of 33 meV is observed in the vicinity of the BL energy. We propose that the peak energy...

Selectively Excited Blue Luminescence in heavily Mg doped p - type GaN

The emission at -2.8 eV from heavily doped p-GaN, known as the blue luminescence (BL), has been studied by selective excitation using a dye laser tunable between 2.7-3.0 eV. The peak position and intensity of the BL are found to exhibit an unusual dependence on the excitation photon energy. We have explained our results with a shallow-donor and deep-acceptors pair recombination model which incl...

Optical Properties Of Metastable Shallow Acceptors In Mg‐Doped GaN Layers Grown By Metal‐Organic Vapor Phase Epitaxy

GaN layers doped by Mg show a metastable behavior of the near-band-gap luminescence caused by electron irradiation or UV excitation. At low temperatures < 30 K the changes in luminescence are permanent. Heating to room temperature recovers the initial low temperature spectrum shape completely. Two acceptors are involved in the recombination process as confirmed by transient PL. In as-grown samp...

Vacancy defects as compensating centers in Mg-doped GaN.

We apply positron annihilation spectroscopy to identify V(N)-Mg(Ga) complexes as native defects in Mg-doped GaN. These defects dissociate in postgrowth annealings at 500-800 degrees C. We conclude that V(N)-Mg(Ga) complexes contribute to the electrical compensation of Mg as well as the activation of p-type conductivity in the annealing. The observation of V(N)-Mg(Ga) complexes confirms that vac...