Laboratory of Physics of Complex Matter (LPMC), Ecole Polytechnique Fédérale de Lausanne, Centre Est, Station 3, CH-1015 Lausanne, Switzerland.
Centre Suisse d'Electronique et de Microtechnique (CSEM SA), CH-2002 Neuchatel, Switzerland.
ACS Nano. 2021 Mar 23;15(3):4077-4084. doi: 10.1021/acsnano.0c07993. Epub 2021 Feb 17.
X-ray photon detection is important for a wide range of applications. The highest demand, however, comes from medical imaging, which requires cost-effective, high-resolution detectors operating at low-photon flux, therefore stimulating the search for novel materials and new approaches. Recently, hybrid halide perovskite CHNHPbI (MAPbI) has attracted considerable attention due to its advantageous optoelectronic properties and low fabrication costs. The presence of heavy atoms, providing a high scattering cross-section for photons, makes this material a perfect candidate for X-ray detection. Despite the already-successful demonstrations of efficiency in detection, its integration into standard microelectronics fabrication processes is still pending. Here, we demonstrate a promising method for building X-ray detector units by 3D aerosol jet printing with a record sensitivity of 2.2 × 10 μC Gy cm when detecting 8 keV photons at dose rates below 1 μGy/s (detection limit 0.12 μGy/s), a 4-fold improvement on the best-in-class devices. An introduction of MAPbI-based detection into medical imaging would significantly reduce health hazards related to the strongly ionizing X-rays' photons.
X 射线光子探测在广泛的应用中非常重要。然而,最高的需求来自医学成像,它需要具有成本效益、高分辨率、在低光子通量下工作的探测器,因此刺激了对新型材料和新方法的探索。最近,混合卤化物钙钛矿 CHNHPbI(MAPbI)由于其优越的光电性能和低廉的制造成本而引起了相当大的关注。重原子的存在为光子提供了高散射截面,使这种材料成为 X 射线探测的理想候选材料。尽管已经成功证明了在检测方面的效率,但它在标准微电子制造工艺中的集成仍然悬而未决。在这里,我们展示了一种通过 3D 气溶胶喷射印刷构建 X 射线探测器单元的有前途的方法,在以低于 1 μGy/s(检测限 0.12 μGy/s)的剂量率检测 8keV 光子时,其灵敏度达到了创纪录的 2.2×10μC Gy cm,比同类最佳器件提高了 4 倍。将基于 MAPbI 的检测引入医学成像将显著降低与强电离 X 射线光子相关的健康危害。