Effects of ion bombardment to interfaces on residual internal stress and crystallite structures on multilayered films

The multilayers with 30 periods of Ni81Fe19/Cu bilayers were deposited by dual ion beam sputtering method. Only two monolayers at interfaces in [Ni81Fe19/Cu](30) multilayers deposited by Ar and/or Kr sputtering were exposed to ion bombardment to change the interfacial situations, such as sharp interface, the local mixing and the interfacial diffusion. In this study, the relationship between residual internal stress and interfacial structure was investigated. The reduction of residual stress was attained by effect of Ar ion bombardment to interfaces at the restricted acceleration voltage of 160 Vfor the films by Ar sputtering and 140 V for the films by Kr sputtering, where clear interfaces and the best crystallinity seems to be attained in the multilayers. (C) 1998 Elsevier Science Ltd. All rights reserved.