The cubic Siliconcarbide (3C-SiC) polytype is one of over 200 different ways to crystallize the wide bandgap semiconductor SiC. For further research and industrial applications only four different types are relevant: 4H, 6H (hexagonal), 15R (rhombohedral) and 3C (cubic). With the lowest bandgap the 3C-SiC type leads to a variety of electronical applications like MOSFETs and IBSCs. This work presents the fundamentals of intermediate band gap solar cells and describes a way of growth and doping 3C-SiC crystals using the fast sublimation growth process in a physical vapor transport setup.