Corrosion hard CVD diamond alpha particle detectors for nuclear liquid source monitoring

Corrosion hard alpha particle detectors have been fabricated from thin diam ond layers grown on silicon using the microwave enhanced chemical vapour de position technique (CVD). The devices can be directly immersed in radioacti ve liquid solutions and enable the real time and in situ measurement of the ir alpha activity. We report here measurements on devices immersed in a plu tonium-239 radioactive source diluted in concentrated nitric acid. The test s have shown excellent reliability of the CVD diamond detectors which would be of great benefit in monitoring nuclear fuel assembly reprocessing. We b elieve that this is the first detection application of CVD diamond which re lies on its corrosion hardness. (C) 2000 Elsevier Science S.A. All rights r eserved.