Laura Basiricò (Università di Bologna)
The attention on the application of organic and hybrid (e.g. based on perovskites) electronics for the detection of ionizing radiation is rapidly growing among the international scientific community, due to the great potential of these technologies to envisage the need of large-area conformable sensor flat panels.
In recent years, our group reported about the employment of solution-grown organic/hybrid devices as reliable direct X-ray detectors, operating at room temperature, opening the way to the development of a new class of flexible direct X-ray detectors based on organic small molecules, e.g. TIPS-pentacene thin films, and on thin film perovskite-based photodiodes with sensitivity values up to thousands of µC/Gy cm2 at ultra-low bias, i.e. below 1 V [1-5].
In this framework, with the project FIRE (CSN5), we propose to develop innovative radiation detectors based on Organic Thin Film Transistors (OTFTs) in both direct and indirect configurations. We aim at detecting different radiation fields (X and gamma-rays, charged particles and neutrons) by tuning the optical and electrical properties of organic materials through their molecular structure. In particular, we aim to develop:
1) indirect detectors based on Organic Photo Transistors (OPTs) coupled with plastic scintillators. Organic semiconductors are very efficient for near UV-IR light detection. We will fabricate OPTs with a photoresponse optimized for the light emission from organic scintillators synthetized in our laboratories. Polymeric scintillators (e.g. Polysiloxanes) will be developed where the higher average Z of the monomeric unit based on silicon can be exploited for applications in High Energy Physics. Suitable compounds of Li and B will be used to enhance thermal neutron detection. OTFTs will be fabricated with lithographic processes, with Au electrodes on flexible PEN substrates.
2) direct X-ray detectors based on semiconducting organic thin films OTFTs. We will develop novel X- and gamma-ray OTFT detectors by appropriately selecting novel and more efficient organic molecules (e.g. TIPGe) and by adding high Z molecules/compounds in the blend of the sensing organic thin film.
The FIRE project will develop an innovative, multidisciplinary and synergic collaboration between INFN research units, that will thrust INFN in a relevant position in the European landscape of flexible and sustainable organic electronics and sensors.
[1] B. Fraboni et al., Adv. Mater.,24,2289 (2012).
[2] L. Basiricò et al., Nat. Commun., 7, 13063 (2016).
[3] A. Ciavatti et al., Adv. Funct. Mater., 1806119 (2018).
[4] Basiricò et al., Adv. Funct. Mater. 29, 1902346 (2019).
[5] Basiricò et al., Frontiers in Physics, 2020, in press.