CONVERGENT-BEAM ELECTRON-DIFFRACTION

The development of new materials requires an understanding of their mode of growth and the nature of defects, interfaces and strains thereby incorporated. This paper shows how convergent beam electron diffraction (CBED) and large angle CBED (LACBED) can be used to analyse such problems. It is shown how CBED and LACBED can give two-beam rocking curves, which can be used to profile plane rotations, strain and composition in multilayer structures, and to determine rigid body displacements at stacking faults and interfaces. In addition LACBED has become a powerful technique for the analysis of dislocations. The recent application of LACBED to determine the Burgers vectors of stair-rod and other partial dislocations is explained.