Fig. 11: Topographs of the 50 µm oxide ridge patterned in the InGaAs layer on an InP substrate taken at 12 keV at two different distances: 0 cm (a) and 20 cm (b). Fine interference patterns are clearly seen at the edge of the oxide ridge at a distance. Interference fringe pattern originated from X-rays deflected in the plane normal to the diffraction plane.