AlGaN/GaN High Electron Mobility Transistors (HEMT) for RF application have been manufactured on SiC substrates thinned with a cold-split method, which allows a cost-effective wafering process. A properly tuned epitaxial growth process allowed depositing very uniform epitaxial layers, and the devices realized on those layers exhibited state of the art characteristics of HEMTs realized on standard substrates. This constitutes a successful first step for introducing an alternative wafering technology which significantly decreases material costs for SiC devices – without device performance degradation. It also proves the robustness of the epitaxial process and its adaptability to thinner SiC substrates.