4. GaN quantum dots doped with rare-earth ions

Based on the above considerations, CEA-Grenoble and the Japanese company NGK Insulators (Nagoya) decided to study the potential of nitride quantum dots doped with rare-earth ions, with a view to producing white light-emitting diodes.

Firstly, will the presence of rare-earth flux disrupt box nucleation? This question is relevant if we consider that rare-earth atoms are large relative to nitrogen and Ga, and tend to accumulate on the surface of the growing layer. Do the resulting change in surface energy and the disruption of adatom (N and Ga) diffusion processes on the surface of the growing layer play a role?

To answer these questions, we used atomic force microscopy (AFM) to study the nucleation of GaN boxes on an AlN surface for different fluxes of europium Eu, resulting in different europium concentrations in the boxes. The results are...