X-ray diffraction studies of miscut crystal surfaces and overlayers: a dynamical diffraction approach

Abstract

X-ray surface diffraction data from a miscut Fe 3Al crystal and the non-specular crystal-truncation rod of a monolayer Au on a Ge(111) surface are interpreted using the dynamical theory in relation to the structures of surface/interface of thin films and bulk crystals. It is found that in the miscut crystal the X-ray penetration depth depends on the crystal miscut angle due to the boundary effect on the excitation of mode of wave propagation. For the Au/Ge(111) case, the diffracted intensity must be summed up in a kinematical fashion to take account of the scattering from the deposited overlayers. This dynamical calculation scheme provides an absolute scale for intensity versus momentum transfer which is useful for surface and thin film analysis.