Elimination of Ghost Reflections in X-ray Diffraction Topography Using Soller Slits

The appearance of disturbing so-called ghost reflections and their shape in X-ray topographs are explained geometrically in real and reciprocal space. It is shown that the introduction of a moving Soller slit placed between single-crystal wafer and film, instead of the conventional secondary slit, overcomes the problem of imaging ghosts in X-ray diffraction topography according to Lang.