Published online by Cambridge University Press: 25 February 2011
Results are presented from glancing angle EXAFS studies of three tungsten-carbon multilayer systems, of different W/C thickness ratios, by monitoring the fine structure above the tungsten L3-edge. The purpose of the investigations was to determine the structural changes occurring in the multilayer as a result of moderate annealing. Surprisingly, dramatic changes are observed in the structural environment of the W atoms as a result of heating to temperatures as low as 350°C for 3 hours. It is found that, when the W layer is sufficiently thick, and the W/C layer thickness favorable, W2C is preferentially formed and crystallization is extensive.
The experiment demonstrates the suitablility of the EXAFS technique for the study of multilayer systems since, 1) contribution to the signal from the interface is significant and 2) the phenomenon is not dependent on the existence of long range order.