Strong orange luminescence from AlN whiskers

The AlN whiskers with large yield were synthesized through the direct nitridation of Al column in high temperature plasma provided by arc discharge. The AlN whiskers show pyramid-like morphology with smooth or rough surface. The AlN whiskers exhibit a strong orange emission band at 612 nm with a Gaussian line shape, which might be attributed to the Al vacancy. The mechanism of defect luminescent is investigated.

► AlN whiskers were synthesized in high-temperature plasma.
► AlN whiskers exhibit a strong orange emission band at 612 nm with a Gaussian line.
► Luminescence can be attributed to the transition between the deep Al vacancy acceptor and valence band.
► The strong orange emission is related to the Al vacancy.