Epitaxial lateral overgrowth of GaN on sapphire substrate using high-dose N⁺ -ion-implantation

An epitaxial laterally overgrown (ELOG) GaN layer was deposited on a (0001) sapphire substrate. Here we introduce a maskless and single-step epitaxial lateral overgrowth (ELO) process using high-dose N+ -ion-implantation. We employed high-dose N+ -ion-implantation as an ELO mask instead of usual dielectric material such as Six Ny or SiO₂. The GaN layer was laterally grown over the ion implanted array formed in a stripe pattern of 4 μm width, resulting in a complete coalescence after approximately 2.5 μm of growth in the [0001] direction. Transmission electron microscopy and photoluminescence analysis confirmed the reduced dislocation density of the ELO grown GaN layer.