​Space is not a very hospitable environment... especially for image sensors on orbiting satellites. Space missions are exposed to radiations from solar winds and cosmic rays. Ségolène Dinand devoted her PhD to better understanding how the radiation environment in space affects HgCdTe infrared detectors.

Over the course of her engineering studies, multiple internships in the space sector confirmed her interest in these issues. Ségolène went on to work with the European Space Agency for a year and a half, before joining CEA-Leti for her PhD, in partnership with the ISAE-Supaéro engineering institute and Airbus Defence and Space. Her PhD project was aligned not only with her scientific aspirations but also with her desire to root her research in practical applications.

In a first for her laboratory, Ségolène developed a characterization system to precisely analyze the effects of radiation on HgCdTe photodiodes. With access to the necessary equipment to cool her detectors to 90 K (-183°C), she was able to conduct experiments in conditions closely resembling those experienced by detectors in orbit. Her findings were presented at international conferences. 

Her research will make it possible, firstly, to anticipate declining performance of HgCdTe detectors, and secondly, to identify parameters for increasing their resistance to ionizing and non-ionizing radiation. Orbiting infrared instruments play an essential role in greenhouse gas emissions monitoring, meteorology, astronomy and Earth observation.

Ségolène notes "𝘿𝙪𝙧𝙞𝙣𝙜 𝙢𝙮 𝙋𝙝𝘿, 𝙧𝙚𝙜𝙪𝙡𝙖𝙧 𝙙𝙞𝙖𝙡𝙤𝙜 𝙖𝙣𝙙 𝙘𝙤𝙡𝙡𝙖𝙗𝙤𝙧𝙖𝙩𝙞𝙤𝙣 𝙬𝙞𝙩𝙝 𝙥𝙚𝙤𝙥𝙡𝙚 𝙛𝙧𝙤𝙢 𝙢𝙪𝙡𝙩𝙞𝙥𝙡𝙚 𝙤𝙧𝙜𝙖𝙣𝙞𝙯𝙖𝙩𝙞𝙤𝙣𝙨 𝙥𝙧𝙤𝙫𝙚𝙙 𝙞𝙣𝙫𝙖𝙡𝙪𝙖𝙗𝙡𝙚, 𝙖𝙡𝙡𝙤𝙬𝙞𝙣𝙜 𝙢𝙚 𝙩𝙤 𝙩𝙖𝙠𝙚 𝙢𝙮 𝙧𝙚𝙨𝙚𝙖𝙧𝙘𝙝 𝙛𝙪𝙧𝙩𝙝𝙚𝙧 𝙗𝙮 𝙨𝙩𝙪𝙙𝙮𝙞𝙣𝙜 𝙖 𝙜𝙞𝙫𝙚𝙣 𝙥𝙝𝙚𝙣𝙤𝙢𝙚𝙣𝙤𝙣 𝙛𝙧𝙤𝙢 𝙙𝙞𝙛𝙛𝙚𝙧𝙚𝙣𝙩 𝙥𝙚𝙧𝙨𝙥𝙚𝙘𝙩𝙞𝙫𝙚𝙨."

Acknowledgments:

PhD supervision: CEA-Leti, ISAE Supaéro, Airbus DS

Radiation-related collaboration: ARC-Nucléart, CEA-DAM, CNES.