Temperature-dependent photoluminescence and electron field emission properties of AlN nanotip arrays

Large-scale single-crystalline AlN nanotip arrays have been fabricated via a facile catalysis-free approach using AlCl3 powder and NH3 as starting materials. These nanotips exhibit an intense broad ultraviolet emission centered at 3.28 eV. The field emission features a notable electron current with a low turn-on field. The turn-on and threshold electric field are found to decrease substantially from 7.7 to 3.9 V/μm and 7.9 to 4.1 V/μm, respectively, while the estimated field enhancement factor increases from 483 to 1884 with increasing the ambient-temperature from room temperature to 573 K. The dependence of the photoluminescence and electron field emission with temperature and the possible mechanism involved has systematically been investigated and thus discussed.Department of Applied Physic