Three-DimensionalGaN−Ga2O3Core Shell Structure Revealed by X-Ray Diffraction Microscopy

Abstract

In combination of direct phase retrieval of coherent x-ray diffraction patterns with a novel tomographic reconstruction algorithm, we, for the first time, carried out quantitative 3D imaging of a heat-treated GaN particle with each voxel corresponding to $17\times 17\times 17{\mathrm{nm}}^3$. We observed the platelet structure of GaN and the formation of small islands on the surface of the platelets, and successfully captured the internal $\mathrm{GaN}\mathrm{\text{−}}{\mathrm{Ga}}_2{\mathrm{O}}_3$ core shell structure in three dimensions. This work opens the door for nondestructive and quantitative imaging of 3D morphology and 3D internal structure of a wide range of materials at the nanometer scale resolution that are amorphous or possess only short-range atomic organization.