Raman characterization of Ar⁺ ion‐implanted GaN

Ar + ions were implanted at room temperature in n‐type hexagonal GaN for device isolation purpose. We performed electrical measurements and resonance Raman spectroscopy in order to monitor the electrical and structural changes of non‐annealed and annealed implanted GaN samples. On increasing the implantation dose from 3.4 × 10 12 to 3.4 × 10 14 ions cm −2 , an increase in the electrical isolation and a decrease in the photoluminescence were observed. For a 10 16 ions cm −2 dose, the implanted layer became conductive owing to a hopping mechanism and only the first‐order phonon lines remained observable. After annealing at 900 °C for 30 s, the implanted samples became conductive and the photoluminescence reappeared or increased compared with the non‐annealed samples at same implantation doses, except for the sample implanted at the highest dose, which became insulating.