Preparation of nanostructured GaN films and their field emission enhancement for different substrates

Abstract

Using pulsed laser deposition (PLD) method, we have prepared nanostructured GaN films of the same thickness on Si and SiC substrates, and analyzed their microstructure characterization and field emission properties. The results showed that the substrates of GaN nanostructured films had significant effect on the microstructure and field emission properties. Compared with the GaN nano-film on Si substrate, the field emission from the GaN nano-film on SiC substrate has been significantly improved: its field emission current was increased by orders of magnitude. The field emission enhancement should be originated from the nanocrystalline microstructure and its orientation polarization induced field enhancement effect. Results indicate that to prepare field emission films of outstanding performance, appropriate substrates and crystal microstructures of the films are the key issues.