Structure and stress in Au/Cu two-layer system during annealing at different temperature

In this work, the Au/Cu two-layer systems, with the total thickness equal to 30 nm are studied. The two-layer systems were deposited by thermal evaporation in a UHV system on the silicon substrate at room temperature. After deposition the samples were annealed. We examined samples subjected to thermal cycle with the different maximum temperature. The X-ray diffraction and X-ray reflectometry are performed for systems before and after annealing. It was found that during the cycle of annealing above 150°C starts process of penetration of the Au layer by Cu atoms results in alloying. In Au/Cu systems, the final layer is the ordered Au/Cu₃ phase.