Determination of grain-boundary diffusion of Ag in nanocrystalline Cu by the Hwang-Balluffi method

From the Ag and Cu Auger signals measured on the surface of nanocrystalline Cu/Ag thin bilayers, the temperature dependence of the parameter omega' fo r Ag grain-boundary diffusion in Cu (omega (')=deltak(b)D(b)/delta (s)k(s), where delta and delta (s) are the width of the grain boundary and the segr egated layer and k(b) and k(s) are the grain-boundary and surface segregati on factors, respectively) have been determined by the Hwang-Balluffi method in the C-kinetics regime over the temperature range of 393-428 K. These va lues have been compared with triple products, P=deltak(b)D(b), determined i n the temperature range 584-804 K by Bernardini [Phil. Mag. A 73, 237 (1996 )] using radio tracer technique in the B-kinetics regime and the temperatur e dependence of the surface segregation factor has been extracted. The surf ace segregation energy (34 +/- 16 kJ/mol) agrees well with other data publi shed in the literature. (C) 2001 American Institute of Physics.