Effect of multiple diffuse scattering on the dynamical diffraction of X-rays in nonuniform layer crystals containing microdefects

The problem of diffraction by nonuniform layer systems is solved within the statistical dynamical theory of scattering with allowance for multiple dif fuse scattering. The effect of secondary extinction on the formation of the reflection curves depending on the concentration and the dimensions of mic rodefects and the gradient of the lattice deformation is analyzed based on the numerical calculations performed for a three-layer heterostructure. It is shown that, at low defect concentrations and high values of the gradient of crystal-lattice deformations, the effect of multiple scattering can be ignored.