Fabrication and Study of Optical Properties of LEDs Based on GaN Micropyramids with a Ni/Au/Graphene Semi-Transparent Contact

The results of studies of technological conditions of formation of LEDs on the basis of an InGaN/GaN micropyramid in the core/shell geometry using a semi-transparent Ni/Au/graphene contact have been presented. The structures have been formed by the method of metalorganic vapor-phase epitaxy. The development of the tranfer conditions of large-area graphene obtained by chemical-vapor deposition has allowed the using of it as a contact for current injection. The fabricated LEDs have demonstrated electroluminescence at a wavelength of 520–540 nm. These sources of radiation are of interest for biomedical applications— in particular, for optogenetics.