Perovskite crystals as new conversion material for X and gamma ray direct detection

Despite the development of numerous semiconductor material for X and gamma ray detection, there is still a need for new high Z material, especially for large area imagers. Recently, it has been shown that hybrid organic-inorganic perovskites with structure of APbX₃ (with A= organic or inorganic cation, and X=Cl, Br, I) are very promising candidates for direct conversion X-ray detectors. Demonstrators have been made for medical radiography in integration mode using microcrystallites. Photon counting has been proved to be possible with solution-processed thick freestanding single-crystals perovskite.

In this talk, we will explain the CEA-Leti, Liten, and Néel Institute joint effort to develop this new generation of material. We are currently growing solution processed CH₃NH₃PbBr₃ single crystals. We demonstrate an X-ray sensitivity of 2700 e^-/X at RQA5 beam quality for 7×7×2.5 mm single crystal in integration mode. Next step will be to integrate this material in thick layers onto a large area matrix in the framework of a H2020 project. In parallel, we try to investigate the spectrometric properties of these crystals.