GRAIN-BOUNDARY DIFFUSION EFFECT ON A CR-AG BILAYER SYSTEM

We have investigated the effects of grain-boundary diffusion (GBD) at elevated temperatures on the Auger-electron-spectroscopy (AES) sputter -depth profiles of Cr-Ag bilayers and the GBD process of Ag atoms in C r. In the case of the Cr-Ag bilayer system, the general surface accumu lation method could not be used because a sufficient accumulation time could not be established for the top Cr layer which is vulnerable to oxidation. This fact suggests the need to use a modified surface accum ulation method. The GBD coefficients of Ag atoms in Cr grain boundarie s were estimated by our modified surface-accumulation method. The GBD parameters for Ag in Cr along the grain boundaries were as follows : t he activation energy and the pre-exponential factor for GBD were 0.33 eV and 4.8 x 10(-9) cm(2), respectively.