Surface analysis of functional layers for semiconductor production

Summary Graphite components used as supports during the production of epi-layers need to be sealed by CVD-SiC coating. In connection with the scaling up of the SiC-coating process the requested quality, i.e. the chemical purity and the microstructure has to be guaranteed. Very large discrepancies have been observed between the various analytical methods (NAA, OES-ICP, SNMS, EPMA) on the determination of the impurities of those coatings in a concentration of some ppm and lower. The chemical analysis of such materials is not conventional and is the aim of future investigations. Using microstructural characterization methods a high quality of this coating material has been established for the mentioned application with a unidirectional crystal growth on the <111> direction of the cubic structure. This quality could also be produced in industrial scale using a large CVD-reactor.