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The technique of 13 CH 4 tracer injection through test limiters was applied to study the influence of surface roughness and substrate material on the local 13 C deposition. Spherically shaped graphite limiters with integrated gas injection were prepared with two different grades of surface roughness, ~0.1 μm and ~1 μm. In addition, tungsten limiters with a roughness of ~0.1 μm were used to study the substrate material effect. The limiters were exposed to the SOL plasma for two discharge scenarios, Ohmic and neutral beam heated. The 13 C deposition efficiency -the ratio of the locally deposited to the injected amount of 13 C -and the deposition pattern were evaluated by post-mortem surface analysis. Surface roughness has a pronounced effect and increases the 13 C deposition efficiency on graphite with rougher surface by a factor of 3-5 compared to smoother graphite. On tungsten a factor of 2-4 less carbon is deposited than on graphite with similar surface roughness. A systematically higher amount of 13 C (by a factor 1.5-2.5) was deposited on limiters exposed to Ohmic compared to neutral beam heated plasmas.