AES analysis of interdiffusions in Cr/Au, Ti/Au and TiW/Au multi-layer films

To predict the reliability of gold electrode, interdiffusions in Cr/Au, Ti/Au and TiW/Au multi-layers when thermally treated were investigated by depth profiling of auger electron spectroscopy (AES). The primitive measuring results suggest that all the under-layer metals diffuse in gold layer when thermally treated and the rise of temperature enhances these diffusions. Cr and Ti accumulate at the surface of gold layer in Cr/Au and Ti/Au samples. And it seems that the introduction of W prevents these accumulations in TiW/Au sample. The measurement of nanohardness indicates that the interdiffusion of under-layer metals increase the nanohardness, while annealing decreases the nanohardness of metal films.