Al-enhanced N incorporation in GaNAs alloys grown by chemical beam epitaxy

The N incorporation is studied in AlGaNAs with low Al content grown by chemical beam epitaxy at low temperature using dimethylhydrazine as the N precursor. The incorporation efficiency is significantly enhanced by introducing a relatively low Al concentration. The relation between the N incorporation and N/(N+As) flow ratio for Al concentrations of 0-15% is presented. The highest N incorporation and the best AlGaNAs crystal quality are obtained between 400 °C and 440 °C, where the growth mode starts to change from 2D to 3D. The activation energies for N incorporation in both the 2D and 3D growth mode regions are extracted.