Abstract
The growth process of the altered layer during ion-bombardment was investigated for Cu-Ni alloys at various temperatures by means of simultaneous SIMS and AES measurements. In the latter, both a lower energy Auger spectrum (LEAES) and a higher energy Auger spectrum (HEAES) were measured to elucidate the surface composition of several atomic layers. The initial surface compositions and their changing processes during the ionbombardment differed one another among the SIMS, LEAES and HEAES data for the same sample. Based on the difference in the sampling depth of SIMS, LEAES and HEAES, the in-depth profile of the altered layer was estimated. The changing process of the surface composition was found to vary remarkably with sample temperatures. This fact indicates that diffusion phenomenon plays an important role for the growth process of the altered layer. It was also found that excess defects produced by the ion-bombardment played a predominant role for the diffusion at lower temperatures, while defects in thermodynamical equilibrium predominantly took part in the diffusion at higher temperatures. Taking the thermodynamical surface segregation into consideration, the growth process of the altered layer could be simulated and it was found that the simulated results agreed fairly well with the experimental data.
