Be diffusion in GaN

Beryllium (Be)-diffused GaN samples have been successfully fabricated by depositing Ni/AuBe onto p-GaN and subsequent thermal annealing. It was found that Be atoms can diffuse much faster than Ni atoms. The Be diffusion length is about 0.5 μm for a sample thermally annealed for 5 min at 650 °C. It was also found that although the room temperature photoluminescence (PL) spectra are the same for the Be-diffused samples annealed at different temperatures, low-temperature PL spectra are significantly different for samples annealed at different temperatures. For the sample annealed at 650 °C, a large PL blue shift was observed when the PL measurement temperature was decreased from room temperature to 10 K.