Plasma etching is a crucial step in semiconductor manufacturing. When the plasma is applied on the wafer, chamber cleanliness and reproducibility of the etching process are essential. The trend towards more aggressive etching environments requires advanced chamber components with excellent plasma resistance in the etching chamber. To tackle this issue, there is an increasing interest of better understanding the specific erosion mechanisms of etch resistant ceramics.  At the current state of development, Yttrium-Aluminum-Garnet (YAG) shows promise in highly aggressive etching environments. In this study, we present a novel approach to manufacture highly dense YAG ceramics by means of reactive field assisted sintering technology/ spark plasma sintering (reactive FAST/SPS) of the respective oxides. FAST/SPS offers several advantages over conventional sintering techniques, e.g. shorter processing times, energy and cost efficiency as well as consolidation close to the theoretical density. To better understand the plasma resistance of YAG alternative lanthanides (Lu, Yb, Er) aluminates were created to identify the influence of the lanthanide atom in the YAG type structure on the plasma-material response. For applied characterization, samples were exposed to fluorine based etching plasmas (CF4/O2) using an inductively coupled plasma (ICP) etch chamber. The resulting topography and induced chemical reactions were characterized by atomic force microscopy (AFM) and secondary ion mass spectrometry (SIMS) respectively.