ATOM PROBE CHARACTERISATION OF Co/TRANSITION-METAL MULTILAYER STRUCTURES

Abstract
Cobalt/transition-metal multilayer structures grown on Co field-ion specimens have been analysed by both conventional atom probe (AP) and the position-sensitive atom probe (POSAP). The combination of the two techniques allows the chemical abruptness and the roughness of the interfaces to be studied independently, and can be supported by high resolution transmission electron microscope (HREM) studies of multilayers deposited simultaneously on flat substrates. Layered structures can be formed with sharp interfaces, with epitaxial growth having been observed, even when using only a simple thermal evaporation source. However, growth by this method seems to be somewhat inconsistent, with carbon contamination leading to the formation of interdiffused, and in the extreme even amorphous layers. With the use of electron beam sources in place of filament evaporators, this technique should provide a powerful complement to the more conventional characterisation methods.