title: X-ray fluorescence induced by standing waves in the grazing-incidence and grazing-exit modes: study of the Mg-Co-Zr system.
abstract: The characterization of Mg-Co-Zr tri-layer stacks using X-ray fluorescence induced by X-ray standing waves, in both the grazing-incidence (GI) and the grazing-exit (GE) modes, is presented. The introduction of a slit in the direction of the detector improves the angular resolution by a factor of two and significantly improves the sensitivity of the technique for the chemical characterization of the buried interfaces. By observing the intensity variations of the Mg Kα and Co Lα characteristic emissions as a function of the incident (GI mode) or detection (GE mode) angle, it is shown that the interfaces of the Si/[Mg/Co/Zr] × 30 multilayer are abrupt, whereas in the Si/[Mg/Zr/Co] × 30 multilayer a strong intermixing occurs at the Co-on-Zr interfaces. An explanation of this opposite behavior of the Co-on-Zr and Zr-on-Co interfaces is given by the calculation of the mixing enthalpies of the Co-Mg, Co-Zr and Mg-Zr systems, which shows that the Co-Zr system presents a negative value and the other two systems present positive values. Together with the difference of the surface free energies of Zr and Co, this leads to the Mg/Zr/Co system being considered as a Mg/CoxZry bi-layer stack, with x/y estimated around 3.5.
authors.affiliation: Sorbonne Universités, UPMC Université Paris 06, Laboratoire de Chimie Physique - Matière et Rayonnement, 11 Rue Pierre et Marie Curie, F-75231 Paris Cedex 05, France.
authors.forename: Yuchun
authors.initials: Y
authors.lastname: Tu
authors.affiliation: Sorbonne Universités, UPMC Université Paris 06, Laboratoire de Chimie Physique - Matière et Rayonnement, 11 Rue Pierre et Marie Curie, F-75231 Paris Cedex 05, France.
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Yuan
authors.affiliation: Sorbonne Universités, UPMC Université Paris 06, Laboratoire de Chimie Physique - Matière et Rayonnement, 11 Rue Pierre et Marie Curie, F-75231 Paris Cedex 05, France.
authors.forename: Karine
authors.initials: K
authors.lastname: Le Guen
authors.affiliation: Sorbonne Universités, UPMC Université Paris 06, Laboratoire de Chimie Physique - Matière et Rayonnement, 11 Rue Pierre et Marie Curie, F-75231 Paris Cedex 05, France.
authors.forename: Jean Michel
authors.initials: JM
authors.lastname: André
authors.affiliation: MOE Key Laboratory of Advanced Micro-structured Materials, School of Physics Science and Engineering, Tongji University, Shanghai 200092, People's Republic of China.
authors.forename: Jingtao
authors.initials: J
authors.lastname: Zhu
authors.affiliation: MOE Key Laboratory of Advanced Micro-structured Materials, School of Physics Science and Engineering, Tongji University, Shanghai 200092, People's Republic of China.
authors.forename: Zhanshan
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Laboratoire Charles Fabry, Institut d'Optique, CNRS UMR 8501, Université Paris Sud 11, 2 Avenue Augustin Fresnel, F-91127 Palaiseau Cedex, France.
authors.forename: Françoise
authors.initials: F
authors.lastname: Bridou
authors.affiliation: CNR-Istituto Officina Materiali, I-34149 Trieste, Italy.
authors.forename: Angelo
authors.initials: A
authors.lastname: Giglia
authors.affiliation: Sorbonne Universités, UPMC Université Paris 06, Laboratoire de Chimie Physique - Matière et Rayonnement, 11 Rue Pierre et Marie Curie, F-75231 Paris Cedex 05, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Jonnard
keywords: X-ray fluorescence; X-ray standing wave; interface; multilayer