Thin film aluminum–gold interface interactions

Thin film diffusion couples of 1 μm Au with 0.3 μm and 1 μm Al were annealed at different temperatures and for different times and the resulting interface reactions were tracked by X-ray diffraction and electron microscopy. The phase formation sequence was identified and the interface microstructure was shown to consist of layers of the different phases. Interface tracking by secondary ion mass spectroscopy depth profiling showed that Au is the predominant diffusant in this system. Intermetallic thickness measurements were made and the activation energy calculated.