Synthesis and phase transformation of Al-Cu-Fe coatings by various processes

Despite considerable advances in co-sputtering deposition process optimisation, there is rather limited work reported on the effects of process variables on the final deposit characteristics. This article considers the effects of process parameters on the deposition of Al-Cu-Fe quasi-crystalline coatings on silicon (100) substrates. A magnetron co-sputtering system was used to produce a series of deposits. The process variables of parameters, such as sputtering powers and annealing temperatures and times, are correlated and discussed. Scanning electron microscopy, atomic force microscopy and X-ray diffraction are used to analyse the deposited coatings in terms of elemental composition and structure characteristics in the deposition. Sputtering powers are found to be a vital parameter in determining the surface roughness and the maximum grain width of the coatings. An inverse relation between the annealing temperatures and the phase transformations of the beta and i phases is observed.