CSiTF solar cells are being intensively investigated due to their cost reduction potential compared to silicon wafer solar cells. At the Fraunhofer ISE several high-temperature approaches are under investigation. Our main interest is focussed on low-cost silicon ribbons and on ceramics as substrate material for such solar cells because they match most requirements best. The silicon substrates are being prepared by a ribbon technique, namely the silicon sheets from powder (SSP) technique using silicon powder of different purity as starting material. Onto these substrates silicon layer systems for CSiTF solar cells are deposited by APCVD from SiHCl3 with high deposition rates and recrystallized by a melting step in order to achieve large crystallites in the active layer. The same layer systems have been studied on different kinds of ceramic substrates like SiSiC, SiN, graphite and mullite. To prevent diffusion of impurities from the substrates into the active silicon layer, different types of barrier layers have been used. On SSP substrates made of EG-SI powder conversion efficiencies up to 11.2% on those of UMG-Si 8.6% could be achieved. On ceramic substrates, efficiencies were up to 11% on graphite, up to 9.3% on SiSiC, up to 8.0% on SIN, and up to 8.2% on mullite.