Silicon doping

Our BR2 reactor plays a significant part in the semi-conductor industry with the production of NTD silicon: Neutron Transmutation Doped silicon.

Superior quality

Doped silicon is an exceptionally pure form of silicon with a strictly controlled minimum supplementation of a related chemical element: phosphorus. Phosphorus can be produced from silicon via a nuclear reaction in a nuclear reactor, i.e. when irradiated silicon absorbs neutrons, which creates phosphorus. The ratio is 1 added phosphorus atom per 1 billion silicon atoms. Because of its specific characteristics our BR2 reactor is particularly suitable for the ‘doping’ of silicon crystals of various diameters in accordance with the highest quality requirements.


Doped silicon is a perfect semi-conductor for high energy electrical applications such as wind turbines, solar energy installations, hybrid vehicles and high speed trains. This semi-conductor facilitates the efficient transport of electricity over very long distances. All these applications require very homogenous doped silicon – our speciality thanks to the BR2 reactor.

Annual production

We mainly work on behalf of silicon producers in Japan and China. They send crystals of various diameters (4, 5, 6 or 8 inch) to SCK•CEN. We produce 15 to 25 tons of doped silicon annually in two installations (SIDONIE and POSEIDON) specifically developed for this purpose.

Once irradiated we keep the crystals for conditioning purposes, which includes cleaning, inspection and packaging. The crystals are then shipped back to the silicon producers, who process the crystals into wafers (chips) and electronic components. All our operations are subject to the stringent ISO 9001:2000 quality controls.

Future opportunities

In the future, doped silicon applications will undoubtedly gain even greater importance as a result of the increasing significance of renewable energy sources and efficient use of electricity.

In recent years, we have doubled the irradiation capacity for silicon and thus, SCK•CEN has an ever greater contribution to the success of renewable energy.



More information on our Science Platform