Aluminium nitride (AlN) is a nitride of aluminium. Its wurtzite phase (w-AlN) is a wide band gap (6.01-6.05 eV at room temperature) semiconductor material, giving it potential application for deep ultraviolet optoelectronics.
A 0625 (OTTO) Aluminium nitride, 99.5% Cas 24304-00-5 - used to build piezoelectric micromachined ultrasound transducers, which emit and receive ultrasound and which can be used for in-air rangefinding over distances of up to a meter.