X-Ray Scattering by Artificially Lateral Semiconductor Nanostructures

Abstract

A simple crystalline surface grating can be assumed to be a three-dimensional crystalline lattice modulated by a one- or two-dimensional mesoscopic superstructure with characteristic dimensions of a few nanometers up to a few microns. The scattering process includes the diffraction by the crystal lattice and by the superstructure. In reciprocal space the crystal lattice is represented by reciprocal lattice points. The superstructure of the grating creates a fine structure of the reciprocal lattice points Supposing, for example, a surface grating patterning a pseudomorphic, vertically layered sample (e.g., a planar multilayer), the fine structure consists of a central crystal truncation rod, corresponding to the mean vertically layered stack, surrounded by a socalled grating rod generated by the grating. Figure 12.1 shows this situation for several reciprocal lattice points in the case of a one-dimensional surface grating (for example an array of quantum wires).