Effects of heavy Si doping on the structural and optical properties of n-GaN/AlN/Si(111) heterostructures

Abstract n-GaN/ AlN heterostructures were grown by molecular beam epitaxy on Si(111) substrates.The GaN films n-type doped with silicon and the effect of doping concentration structural optical properties was studied. Si promotes a reduction dislocation density as revealed x-ray data analysis Transmission Electron Microscopy. Furthermore, decrease in yellow band measured Photoluminescence Spectroscopy observed when increased up to 1.7 × 10 19 atoms cm −3 . A particular mosaic structure induced Si-doping inferred from Rutherford Backscattering measurements. The crystal quality shows small degradation for very heavily samples (1.3 20 ).