We have investigated the growth of SiC, following a modified sol-gel process, which not only allows the realization of 3D photonic bandgap materials but also is useful for various SiC applications like templates in medicine or filters in harsh environment. Depending on the sol-gel annealing procedure one obtains macro-porous SiC, amorphous SiC, or from nano to micrometer-sized 3C-SiC single crystals. At low annealing temperatures preferably nanowires are grown. Via various sol-gel-annealing procedures we are able to prepare single crystals with sizes ranging from several nm up to several 100 %m, while the resulting polytype only depends on the annealing temperature available. Not only for photonic applications useable procedures for doping with shallow level donors and acceptors as well as with deep level defects are essential. We show that controlled doping is possible either during the sol-gel preparation or via the gas phase during the following annealing procedure.