Caracterisation structurale par XRD de RHEED de couches minces epitaxiees de GaN deposees sur Al_2O_3(0001) par ablation laser reactive

摘要

Thin epitaxial films of GaN have been deposited on Al_2O_3(0001) by reactive laser ablation. A nitruration of the substrate prior to deposition is mandatory in order to order to obtain epitaxial films The state of crystallinity of the thin films has been characterized using X-rays and electron diffraction (XRD and RHEED). A clear correlation has been established between the observed RHEED images and the shape of the X-rays peaks measured by the rocking-curve method. This correlation allows to control in-situ the growth of the GaN film and therefor to control its crystalline quality.