Flexible fully organic indirect detector for megaelectronvolts proton beams

Abstract

A flexible, fully organic detector for proton beams is presented here. The detector operates in the indirect mode and is composed of a polysiloxane-based scintillating layer coupled to an organic phototransistor, that is assessed for flexibility and low-voltage operation (V = −1 V), with a limit of detection of 0.026 Gy min−1. We present a kinetic model able to precisely reproduce the dynamic response of the device under irradiation and to provide further insight into the physical processes controlling it. This detector is designed to target real-time and in-situ dose monitoring during proton therapy and demonstrates mechanical flexibility and low power operation, assessing its potential employment as a personal dosimeter with high comfort and low risk for the patient. The results show how such a proton detector represents a promising tool for real-time particle detection over a large area and irregular surfaces, suitable for many applications, from experimental scientific research to innovative theranostics.

Solution-processable thin-film transistors from anthradithiophene (ADT) and naphthothiopene (NT) small molecule-based p-type organic semiconductors

“…51 This behaviour is typical of organic phototransistors and is the basis of the light detection mechanism for this type of detector. 52,53 A figure of merit used to evaluate the quality of the light response of a photodetector is the responsivity defined as R = J ph / P opt where J ph is the photocurrent density per unit area. In our case, considering the maximum of the photocurrent as the difference between the I D value at the end of illumination and at the beginning of illumination, we obtain a responsivity value equal to 3.5 A W −1 which is in line with many conventional commercial detectors currently available, and is comparable with the OPTs in literature as reported in ESI † 54–56 .…”

Halide Perovskites and Their Derivatives for Efficient, High‐Resolution Direct Radiation Detection: Design Strategies and Applications

“…On the other hand, the high quantities of lead may prevent halide perovskites from being used for wearable radiation detector monitors. [202] Perovskite-inspired materials (PIMs) describe the classes of compounds investigated as lower toxicity alternatives to leadhalide perovskites. [114] Broadly speaking, there have been three approaches in the community towards discovering PIMs.…”

“…On the other hand, the high quantities of lead may prevent halide perovskites from being used for wearable radiation detector monitors. [ 202 ]…”

Low-Voltage and Highly Sensitive PbS Quantum Dot Thin-Film X-ray Monitors

“…X-ray detection is usually achieved through direct and indirect detectors . Indirect detectors exploit a scintillating material that absorbs energy radiation, producing a more easily detectable lower energy burst of photons, typically in the visible range. − On the other hand, direct detectors can directly convert impinging X-ray radiation into an electrical signal. ,, The latter method of detection usually implies higher energy resolution and conversion efficiency than the former one. , The charge collection in direct X-ray detection is usually performed by organic and inorganic semiconductor materials. Such materials allow us to fabricate smaller and more efficient detectors than equivalent gas-based ionization chambers, thanks to their much higher density and number of carriers produced per event. , …”

“…Solution-processed high-Z nanomaterials have recently gained attention as promising candidates for a new generation of thin-film, easily processable, and low-cost direct X-ray detectors. − ,− …”