Phase relations and the shape of the X-ray rocking curves from heterostructures with quantum wells

A qualitative analysis of the formation of an interference pattern on the X-ray rocking curves from heterostructures with quantum wells has been performed. It has been shown that in addition to the well-known effect associated with the additional phase shift in the diffraction scattering amplitudes of the coating layer and substrate, which is caused by a small shift of the atomic layers in a quantum well, the shape of the reflection curve strongly depends on the quantum-well thickness, manifesting the specific phase relations in the integral reflection amplitude. Simple analytical expressions have been obtained which allow for not only the description of fine details of the interference pattern on the reflection curve, but also the approximate estimation of the most significant parameters of a real grown heterostructure, which determine the most adequate start model for further analysis based on the general formulas of dynamical diffraction.