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In advanced contact materials one aim in processing is the reduction or even substitution of precious metals. However, newly developed materials have to exhibit excellent corrosion resistance and good electrical conductivity as well as mechanical stability, especially if abrasive wear loaded contacts are concerned. One strategy is the total substitution of precious metals by non-noble metals such as copper and its conventional alloys. Such materials, however, suffer from their poor mechanical properties. Chromium would be a candidate for an unusual alloying element that may help to overcome these weaknesses, but unfortunately Cr does not mix with Cu by standard metallurgy. For low current contacts a surface layer of a mixed material might be sufficient, and powder metallurgical routes are therefore inefficient and hence inadequate. The excimer laser is an excellent tool to produce the required thin films by surface alloying. This is possible due to its short wavelength and short pulse duration. The present investigations were carried out in order to understand the phenomenon of laser surface alloying using excimer laser irradiation. To achieve technical relevance, the system Cu/Cr was chosen. The irradiations were monitored using difference reflectometry, to check whether alloying occurred at all and to what degree. Structural details of the produced layers were investigated using a diffractometer with glazing incidence. To obtain quantitative information about depth and stoichiometry of the alloyed layer, sputtering AES was applied.
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