High sensitivity organic inorganic hybrid X-ray detectors with direct transduction and broadband response

H M Thirimanne,D G Lidzey,S Pani,R M I Bandara,A J Parnell,A Karalasingam,S F Tedde,A Nisbet,S R P Silva,J E Huerdler,C A Mills,K D G I Jayawardena

doi:10.1038/s41467-018-05301-6

H M Thirimanne, D G Lidzey + Show 10 more

Open Access

https://doi.org/10.1038/s41467-018-05301-6

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Abstract

X-ray detectors are critical to healthcare diagnostics, cancer therapy and homeland security, with many potential uses limited by system cost and/or detector dimensions. Current X-ray detector sensitivities are limited by the bulk X-ray attenuation of the materials and consequently necessitate thick crystals (~1 mm–1 cm), resulting in rigid structures, high operational voltages and high cost. Here we present a disruptive, flexible, low cost, broadband, and high sensitivity direct X-ray transduction technology produced by embedding high atomic number bismuth oxide nanoparticles in an organic bulk heterojunction. These hybrid detectors demonstrate sensitivities of 1712 µC mGy−1 cm−3 for “soft” X-rays and ~30 and 58 µC mGy−1 cm−3 under 6 and 15 MV “hard” X-rays generated from a medical linear accelerator; strongly competing with the current solid state detectors, all achieved at low bias voltages (−10 V) and low power, enabling detector operation powered by coin cell batteries.

Highlights

X-ray detectors are critical to healthcare diagnostics, cancer therapy and homeland security, with many potential uses limited by system cost and/or detector dimensions
Direct conversion detectors based on materials such as amorphous selenium[2] are currently used in mammography, but are limited by their low Xray attenuation for energies higher than 50 keV
We introduce a broadband, direct, X-ray detector concept based on a thin film, hybrid semiconductor diode consisting of an organic bulk heterojunction (BHJ)—bismuth oxide (Bi2O3) NP composite

Summary

Introduction

X-ray detectors are critical to healthcare diagnostics, cancer therapy and homeland security, with many potential uses limited by system cost and/or detector dimensions. We present a disruptive, flexible, low cost, broadband, and high sensitivity direct X-ray transduction technology produced by embedding high atomic number bismuth oxide nanoparticles in an organic bulk heterojunction. We introduce a broadband, direct, X-ray detector concept based on a thin film, hybrid semiconductor diode consisting of an organic bulk heterojunction (BHJ)—bismuth oxide (Bi2O3) NP composite These direct X-ray detectors demonstrate high sensitivities of 1712 μC mGy−1 cm−3 under 50 kV soft X-rays and ~30 and 58 μC mGy−1 cm−3 under 6 and 15 MV hard X-rays.

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