The impact of the manufacturing process on the radiation-induced degradation effects observed in CMOS image sensors (CISs) at the MGy total ionizing dose (TID) levels is investigated. Moreover, the vulnerability of the partially pinned PHDs at moderate-to-high TIDs is evaluated for the first time to our knowledge (PHD stands for "photodiode"). It is shown that the 3T-standard partially pinned PHD has the lowest dark current before irradiation, but its dark current increases to ∼1 pA at 10 kGy(SiO 2). Beyond 10 kGy(SiO 2), the pixel functionality is lost. The comparison between several CIS technologies points out that the manufacturing process impacts the two main radiation-induced degradations: the threshold voltage shift of the readout chain MOSFETs and the dark current increase. For all the tested technologies, 1.8-V MOSFETs exhibit the lower threshold voltage shift, and the nMOSFETs are the most radiation tolerant. Among all the tested devices, 1.8-V sensors achieve the best dark current performance. Several radiationhardening-by-design solutions are evaluated at the MGy level to improve further the understanding of CIS radiation hardening at extreme TID.

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A series of experimental tests were performed to measure the efficiency of volatile iodine trapping on sand bed filters and metallic filters. These filtering media are used in French nuclear power plants to mitigate releases in case of severe accident. The results show that molecular iodine is more easily trapped than methyl iodide due to its high chemical affinity with stainless steel or with silver and cesium cations included in the filter medium. For methyl iodide, the trapping efficiency is low.

This paper deals with near past, ongoing, and planned R&D works on fission products (FPs) behavior in reactor cooling system (RCS), containment building and in filtered containment venting systems (FCVS) for severe accident (SA) conditions. All the researches are collaborative works; the overall objective is to develop confident models to be implemented in simulation software. After being initiated in 2004, researches on iodine transport through the RCS are still ongoing and for containment, the last advances are linked to the source term (ST) evaluation and mitigation (STEM) OECD/NEA project. The objective is to improve the evaluation of ST for a SA on a nuclear power plant and to reduce uncertainties on specific phenomena dealing with the chemistry of two major FPs: iodine and ruthenium. For ruthenium attention has been paid to study the amount and nature (gas/aerosol partition) of ruthenium species along the RCS. A follow-up, called STEM2, has started to reduce some remaining issues and be closer to reactor conditions. For FCVS works, the efficiencies for trapping iodine covering scrubbers and dry filters are examined to get a clear view of their abilities in SA conditions. Another part is focused on specific porous materials able to trap volatile iodine. Influence of zeolite materials parameters (nature of the counter-ions, structure, Si/Al ratio…) are tested as well as new kind of porous materials constituted by Metal organic Frameworks will also be looked at.

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