Epitaxial Growth Of Gan Films Grown On Single Crystal Fe Substrates

摘要

GaN films have been grown on single crystalline Fe(110), Fe(100), and Fe(111) substrates with low-temperature AlN buffer layers by the use of pulsed laser deposition. AlN films with 30° rotated domains and polycrystalline AlN films grow on Fe(100) and Fe(111), respectively. On the other hand, AlN(0001) films grow epitaxially on Fe(110) substrates. X-ray reflectivity measurements have revealed that the heterointerface of AlN/Fe(110) is quite abrupt and that its abruptness remains unchanged, even after annealing at 700 ℃. GaN epitaxial films have been grown on AlN/Fe(110) structures with an in-plane relationship of GaN[11-20]‖AlN[11-20]‖Fe[001]. The first-principles calculations have revealed that this in-plane epitaxial relationship is determined by the adsorption process of nitrogen atoms on the Fe surfaces at the initial stage of the growth.