We aim at studying materials that exhibit the Quantum Anomalous Hall Effect (QAHE) and understand the underlying mechanisms that provide the fine balance of ferromagnetic doping and low carrier density. The quantized version of the Anomalous Hall Effect has been the last in the family of predicted Hall effects that was finally experimentally confirmed by Chang et al. In 2013. The essential ingredients are ferromagnetically doped topological insulators that show a gap opening in the topological surface state band structure while also having a low background carrier density. Little is known about the magnetic properties of the MBE (molecular beam epitaxy) grown thin films. Potential device applications crucially depend on strategies to increase the Curie temperature of currently ~15K by proximity coupling. Our goal is to study the interfaces and thin films of precisely engineered thin film