Experimental characterisation of FIB induced lateral damage on silicon carbide samples

As the importance of well-defined micro- and nanostructures increases in various application fields, e.g. photonics, photovoltaics and biology (e.g. as electrodes for biomedical applications or patterned surfaces for cell surface interaction studies), the qualification of the involved fabrication tools is of major importance. Especially for prototyping of such structures or devices the use of focused ion beam (FIB) systems for structuring is often attractive due to the flexibly controllable, highly focused ion beam (spot size down to 7 nm and below). However, one has to take into account that FIB processing might lead to electrically relevant damage which has a much larger lateral extension than the intentionally irradiated area. As shown on silicon samples scanning spreading resistance microscopy (SSRM) is a very sensitive tool to investigate damage caused by FIB irradiance even for doses which do not result in a change of topography. This work focuses on silicon carbide (SiC), as the material has risen in popularity and application due to its advantageous properties in power electronics compared to silicon and where FIB induced lateral damage has not been systematically investigated yet.