An analytical approach of the HOLZ lines splitting on relaxed samples

Abstract

For many years, Convergent Beam Electron Diffraction (CBED) has been intensively used for lattice parameter determination because of the extremely high sensitivity of High Order Laue Zone (HOLZ) lines position to small lattice parameter changes. But, for highly stressed systems, the sample thinning down to electron transparency induces a relaxation. In such cases, HOLZ lines are splitted due to an inhomogeneous variation of lattice parameter (Figure 1.a). Conventional measurement of lattice parameter using quasi-kinematical approach of HOLZ lines shift is then impossible and new models have to be developed. Recently, several approaches have been proposed in order to reproduce the experimental profile of split HOLZ lines also called “rocking curves” I g(s), and deduce the stress distribution in the sample [1, 2, 3, 4]. But, several questions are still open and relation between the rocking curve features and the atomic displacement profile is not completely understood.