Grazing-incidence x-ray diffraction from GaN epitaxial layers withthreading dislocations

Abstract

We used high-resolution x-ray reciprocal space mapping in noncoplanar grazing-incidence geometry for the determination of the density of edge threading dislocations in c-oriented GaN epitaxial layers and we compared the measured intensity distributions with results of numerical Monte Carlo simulations of diffuse scattering. We demonstrated that a combination of diffraction data taken in coplanar symmetric and noncoplanar grazing-incidence geometries makes it possible to obtain the densities of screw and edge threading dislocations. (C) 2011 American Institute of Physics. [doi:10.1063/1.3543842]

Keywords

• Grazing-incidence
• x-ray
• diffraction
• GaN
• epitaxial
• layers
• withthreading
• dislocations