Neutron transmutation doping of silicon at the SAFARI-1 research reactor

The production of NTD of silicon grew from a humble R and D project at SAFARI-1 in 1990 to a full scale commercial programme, as a joint venture between the groups SAFARI-1 Research Reactor and Nuclear Technology Products (NTP) at Necsa. SAFARI-1 acts as an irradiation service provider to NTP, which is responsible for the commercial management of the various irradiation products stemming from the reactor. Detailed characterization and careful selection of the irradiation position lead to the production of acceptable NTD of silicon. The unique translational and rotational process ensures an almost homogeneous dopant concentration without the burden of flux flattening shields, which would result in unacceptable lower thermal flux levels. The fact that acceptable NTD of silicon can be produced with a light water moderated reactor, contrary to earlier beliefs, may also be attributed to improved crystal growth processes, as well as post-irradiation annealing techniques. Utilizing the pool side of SAFARI-1 for the production of NTD of silicon without impairing the reactor core, leaves the core available for the production of medical isotopes and material research, requiring higher thermal neutron fluxes. The commercial utilization at SAFARI-1 is complemented with state of the art neutron radiography, tomography and diffraction facilities available at the beam ports