Effective reduction of AlN defect luminescence by fluorine implantation

We report on the effective reduction of AlN host lattice defect cathodoluminescence by high dose ion implantation of light elements such as fluorine as well as chlorine and neon with peak concentrations of 1 at.%. In order to distinguish between luminescence suppression in the visible to luminescence quenching due to radiation damage, all samples were additionally implanted with europium at fluences of 1 · 10¹³ ions/cm². After annealing the samples at 1373 K under vacuum conditions cathodoluminescence spectra were recorded at room temperature (300 K) and at cryogenic temperature (12 K). These investigations reveal that different light ion species have different influences on the defect luminescence of the AlN host lattice which is likely due to selective passivation of these defects. The best ratio of defect luminescence suppression to radiation damage induced luminescence quenching is achieved in the case of fluorine co-doping.