Low‐Cost and Large‐Area Hybrid X‐Ray Detectors Combining Direct Perovskite Semiconductor and Indirect Scintillator
Weijun Li, Lulu Liu, Mingrui Tan, Yuhong He, Chunjie Guo, Huimao Zhang, Haotong Wei, Bai Yang
Abstract
Abstract Both semiconductors and scintillators have their own advantages in direct and indirect X‐ray detection, respectively. However, they are also limited by their intrinsic properties and detection mechanisms. Here, a low‐cost and large‐area flat X‐ray detector is reported by combining a cesium silver bismuth bromide (Cs 2 AgBiBr 6 ) perovskite semiconductor with a ethylenebis‐triphenylphosphonium manganese (II) bromide ((C 38 H 34 P 2 )MnBr 4 ) scintillator through fast tableting processes. Cs 2 AgBiBr 6 and (C 38 H 34 P 2 )MnBr 4 can attenuate the X‐ray photons to induce charge carriers that are collected through the continuous Cs 2 AgBiBr 6 grains. (C 38 H 34 P 2 )MnBr 4 blocks the Cs 2 AgBiBr 6 ions migration paths at the grain boundaries to reduce the device dark current/noise and improves the working stability. Most charges generated by (C 38 H 34 P 2 )MnBr 4 are transferred to the adjacent Cs 2 AgBiBr 6 , and recombined charges radiate light through scintillation, which will be further absorbed by the surrounding Cs 2 AgBiBr 6 perovskite, and further induce collectable charges for indirect X‐ray detection, avoiding the unwanted light scattering, self‐absorption, or afterglow effects of scintillators. The hybrid X‐ray detector displays a high sensitivity of 114 µC Gy air −1 cm −2 to 120 keV p hard X‐rays with a lowest detectable dose rate of 0.2 μGy air s −1 , showing 75 times lower detection limit compared to (C 38 H 34 P 2 )MnBr 4 scintillator, which provides a new path for X‐ray flat‐panel design.