MICROSTRUCTURE AND STRAIN IN ELECTRODEPOSITED CN NI MULTILAYERS/

Electrodeposited Cu/Ni multilayers with different modulation lengths L ambda = 4-18 nm were examined by means of x-ray diffraction and transm ission electron microscopy. Preferred orientations of [111], [110], an d [001]-types, as determined from relative x-ray diffraction peak inte nsities, were seen in the multilayers. By means of computer simulation s of the measured x-ray diffraction spectra, several parameters of the multilayers, such as Lambda-values and fluctuations Delta Lambda, as well as lattice strain, were determined. Multilayers having large Lamb da were found to be fully relaxed due to interfacial dislocation forma tion. In short Lambda [001]-texture multilayers partial strain relaxat ion occurs, probably due to the incorporation of Cu into the Ni layers . Both of the processes lead to the diffuse Cu/Ni interfaces. Short wa velength multilayers with a [111]-preferred orientation were almost fu lly strained. The importance of the [111]-texture in the improvement o f mechanical strength of Cu/Ni multilayers resulting from its enhanced ability for stain accommodation is discussed.