J. Phys. IV France 06 (1996) C7-125-C7-134
Residual Stresses in Metallic MultilayersO. Thomas1, P. Gergaud1, S. Labat1, L. Barrallier2, A. Charaï3, C. Alfonso3, B. Gilles4 and A. Marty4
1 MATOP, URA 1530 du CNRS, Faculté de Saint Jérôme, 13397 Marseille cedex 20, France
2 MécaSurf, CER ENSAM, 13617 Aix-en-Provence cedex 1, France
3 EDIFIS, URA 443 du CNRS, Faculté de Saint Jérôme, 13397 Marseille cedex 20, France
4 CEA/DRFMC/SP2M, Centre d'Études Nucléaires, 38054 Grenoble cedex 9, France
The study of residual stresses in metallic superlattices is of great importance. Properties of these materials are a consequence of their extreme strain states. With respect to single films, both the determination methods and the magnitude of the stresses may differ in multilayers. X-ray strain determination must be used with caution because of possible interference effects. The large amount of disorder tends to suppress the modulation on asymmetrical peaks. Stress deduced from wafer bending experiments may contain a non negligible interfacial contribution. The very large stresses (≥1GPa) determined in the superlattices imply very high yield stresses, possibly related to size effects. Anomalous strain free lattice parameters are frequently reported. They may be related to the occurrence of segregation during the growth.
© EDP Sciences 1996