High-sensitivity high-resolution X-ray imaging with soft-sintered metal halide perovskites

Abstract

To realize the potential of artificial intelligence in medical imaging, improvements in imaging capabilities are required, as well as advances in computing power and algorithms. Hybrid inorganic–organic metal halide perovskites, such as methylammonium lead triiodide (MAPbI3), offer strong X-ray absorption, high carrier mobilities (µ) and long carrier lifetimes (τ), and they are promising materials for use in X-ray imaging. However, their incorporation into pixelated sensing arrays remains challenging. Here we show that X-ray flat-panel detector arrays based on microcrystalline MAPbI3 can be created using a two-step manufacturing process. Our approach is based on the mechanical soft sintering of a freestanding absorber layer and the subsequent integration of this layer on a pixelated backplane. Freestanding microcrystalline MAPbI3 wafers exhibit a sensitivity of 9,300 µC Gyair–1 cm–2 with a μτ product of 4 × 10–4 cm2 V–1, and the resulting X-ray imaging detector, which has 508 pixels per inch, combines a high spatial resolution of 6 line pairs per millimetre with a low detection limit of 0.22 nGyair per frame.

Coupling between Ion Drift and Kinetics of Electronic Current Transients in MAPbBr3 Single Crystals

“… 1 , 2 In the case of halide perovskite single crystals (SCs), the promising sensitivity and favorable characteristics (high absorption coefficient, long carrier diffusion length, and long carrier lifetime) have motivated arduous research in the field of high-energy radiation detectors. 3 − 5 Particularly, the use of methylammonium lead tribromide (MAPbBr 3 ) SCs for radiation detectors has recently shown significant progress 6 − 8 because of their easy solution-based fabrication methods and the resulting high crystalline quality and material stability. 9 − 11 Nevertheless, unravelling the working mechanisms of halide perovskite-based devices remains challenging because of their mixed ionic–electronic conductive nature, which usually complicates the comprehension of certain response features.…”

Highly Efficient and Flexible Scintillation Screen Based on Manganese (II) Activated 2D Perovskite for Planar and Nonplanar High‐Resolution X‐Ray Imaging

“…As a demonstrative experiment, the internal structures in metal, plastic and biological tissue specimens can be clearly imaged on the scintillation screen depending on the difference in X-ray absorption (Figure 3h). Due to the diversity in density between imaging targets, the generated X-ray energy distribution can be modulated by altering the applied voltage (from 6 to 40 kV) of the X-ray source for realizing a proper penetration depth [6] (Table S3, Supporting Information). As shown in Figure S16 from the Supporting Information, the sensitivity to X-ray of different energies also shows the potential of this scintillation screen in dual-or even multienergy X-ray detectors.…”

“…[5] Modern X-ray detectors with the advantages of digital image processing, massive storage capability, data sharing have almost replaced the traditional film-based detectors. Currently, two available schemes were adopted for X-ray detection: direct-detection based on semiconductor materials operating in currentto-current mode, [6][7][8] and indirect-detection based on scintillators working in photonto-current mode. [9][10][11][12][13][14][15][16][17][18] Indirect-detection type X-ray detectors occupy the majority of the market share because of their relatively low-cost and stability.…”

Inch-Sized Thin Metal Halide Perovskite Single-Crystal Wafers for Sensitive X-Ray Detection

“…But α-Se detectors have low sensitivity and require high dose for imaging, which brings cancer risk to the patients (Kasap et al, 2000). In comparison, the sensitivity of perovskite X-ray detectors are several orders of magnitude larger than that of commercial α-Se detectors, especially for hard X-ray (Wang et al, 2020;Deumel et al, 2021;Liu et al, 2021a;Peng et al, 2021).…”