Surface smoothing and patterning of SiC by focused ion beams

6H-SiC was irradiated at room temperature with focused Ga+ or Au+-beams at different energies and ion fluences. The bombarded areas were investigated by means of atomic force microscopy. The measurements indicate a smoothing of the irradiated areas saturated at ion fluences of 7×1016 Ga+ cm−2. For higher ion fluences, sputtering dominates over a swelling, which is induced by irradiation damage and ion implantation. SiC can be removed in a well-defined three-dimensional geometry with a slope of the sidewalls up to 85°, depending on the ratio of the beam diameter and the structure depth. The bottom of the sputtered structures is still very planar. The observed sputtering yields could be well fitted with TRIM 87 simulations using the surface binding energy as an input parameter.