Using electron-induced X-ray emission spectroscopy (XES), we have studied
two Al/Ni periodic multilayers that differ only by their annealing
temperature: as-deposited and annealed at 115 °C. Our aim is to show that
XES can provide further details about the chemistry at the metal-metal
interface, in addition to what is obtained by X-ray diffraction. The
distribution of valence states exhibiting Al 3p and Ni 3d character is
determined from the analysis of the Al$K\beta$ and Ni$L\alpha$ emission
bands respectively. The multilayer emission bands are compared to those of
reference materials: pure Al and Ni metals as well as Al3Ni,
Al3Ni2 and AlNi intermetallics. We provide evidence that, for
temperatures up to 115 °C, Al3Ni is the major component of the
multilayer.