Optical and structural properties of Eu-implanted InxAl1−xN

Abstract

Off-axis implantation of 80 keV Eu ions into epitaxial c-plane InAlN/GaN bilayers confines rare-earth (RE) doping largely to the InAlN layer. Rutherford backscattering spectrometry and x-ray diffraction show good correlations between the Eu3+ emission linewidth and key structural parameters of InxAl1−xN films on GaN in the composition range near lattice matching (x∼0.17). In contrast to GaN:Eu, selectively excited photoluminescence (PL) and PL excitation spectra reveal the presence of a single dominant optical center in InAlN. Eu3+ emission from In0.13Al0.87N:Eu also shows significantly less thermal quenching than GaN:Eu. InAlN films are therefore superior to GaN for RE optical doping.