It is well known that manufactures of power electronic devices rely on FZ silicon wafers of highest possible purity. The manufactures however also have a demand for wafers with lower and lower radial resistivity variation (RRV) across the wafer. The current product on the 200 mm wafer market with the lowest RRV is based on neutron transmutation doping (NTD) where a RRV value lower than 5% is guaranteed for all wafers cut from an ingot. This work presents a novel concept called Advanced NTD which can provide 200 mm wafers with RRV lower than 2%. The radial resistivity profile of an NTD wafer is influenced by the neutron flux in the nuclear reactor. The result is a resistivity that is lower at the edge compared to centre of the wafer. By engineering a gas phase doped profile to be the inverse of the NTD profile, and simultaneously carefully controlling the required NTD doping factor, an almost flat resistivity profile can be achieved by combining the developed gas phase doping process with the NTD process. The capability of the Advanced NTD process is demonstrated in a pilot production of 11 ingots.