Microscopic correlation of doping distribution and luminescence in a nitride laser junction by Photonic Atom Probe

The Photonic Atom Probe is applied to the study of nanoscale field-emission tip specimens containing a section of III-N device constituted by a sequence of alloyed and doped sections. Different sections produce specific but spectrally overlapping luminescence signals. The possibility of collecting photoluminescence spectra during the field evaporation of the specimen allows for disentangling different doping-related luminescence lines and to correlate the different spectral contributions to the specific properties of the doping distributions. In particular, the spectral components of the luminescence related to Mg impurities at energies between 3.0 eV and 3.3 eV have been investigated, and correlated with the Mg concentration and 3D distribution in different sections of the device.