Medical Applications of Tissue-Equivalent, Organic-Based Flexible Direct X-Ray Detectors

Abstract

The aim of this study is to assess direct X-ray detectors based on organic thin films, fabricated onto flexible plastic substrates, and operating at ultra-low bias (<1 V), for different medical applications. With this purpose, flexible fully organic pixelated X-ray detectors have been tested at the imaging beamline SYRMEP (SYnchrotron Radiation for MEdical Physics) at the Italian synchrotron Elettra, Trieste. The detectors' performance has been assessed for potential employment both as reliable wearable personal dosimeters for patients and as flexible X-ray medical imaging systems. A spatial resolution of 1.4 lp mm −1 with a contrast of 0.37 has been evaluated. Finally, we validate the detector using X-ray doses and energies typically employed for actual medical radiography, and using X-ray beam pulses provided by a commercial dental radiography system, recording a sensitivity of 1.6 × 10 5 µC Gy −1 cm −3 with a linear response with increasing of the dose rates and a reliable signal to 100 ms X-rays pulses.

Solution‐Grown Organic and Perovskite X‐Ray Detectors: A New Paradigm for the Direct Detection of Ionizing Radiation

“…More recently, different studies on the X‐ray photoconversion mechanism in full‐organic thin films have been carried out by employing drop cast devices. [ 21,28 ] Thanks to the low‐temperature process required by drop‐casting due to the use of low boiling point solvents, such devices have been demonstrated as reliable flexible and wearable detectors [ 30 ] ( Figure a). In addition, drop‐casted CsPbBr 3 microcrystalline perovskite layer, few micrometer thick, inorganic perovskites have been recently assessed for clinical radiotherapy dosimetry.…”

“…An additional, very relevant property of organic materials is their tissue‐equivalent density, that allows to avoid calibration procedures or correction factors otherwise needed when measuring the radiation dose delivered to biological species with inorganic detectors. [ 29,30 ]…”

Metal Halide Perovskites for High‐Energy Radiation Detection

“…operational stability. [96] Even though commercial systems with excellent X-ray detection abilities do exist, [96,97] the high-cost limits their widespread adoption. MHPs, such as MAPI, MAPbBr 3 , and CsAgBiBr 6 , in their single-crystal form have proven suitable for efficient X-ray detectors but still suffers from the relatively high density of defects, field-induced ion migration, and poor operational stability.…”

Electron Beam Induced Tailoring of Electrical Characteristics of Organic Semiconductor Films

“…The flexibility makes organic film based electronic devices superior over its inorganic counter parts. For flexible device applications such as power sources [74,75], displays [76], electronics [77], super capacitors [78], gas sensors [79][80][81], thermoelectric power generators [82,83], organic light emitting diodes [84,85], radiation dosimeters [86][87][88] etc., organic semiconductors are promptly used. The nature of interaction between high energy EB and organic materials depends on the energy as well as dose of the incident EB [7].…”