Contatto di riferimento: Laura Basirico'
Abstract:
In the field of ionizing radiation detection, organic semiconductors have been proposed so far mainly as indirect detectors, i.e. as scintillators or as photodiodes.
We report about the performances of solution-grown Organic Semiconducting Single Crystals (OSSCs), in particular 4-hdroxycyanobenzene (4HCB), as direct X-ray detector, i.e. a device that direct converts a photon into an electrical signal, assessing that they can operate at room temperature and in atmosphere, showing a stable and linear response with increasing dose rate.
A dedicated study of the collecting electrodes geometry, crystal thickness and interaction volume allowed us to maximize the charge collection efficiency and sensitivity, thus assessing how OSSCs perform at low operating voltages and offer a great potential in the development of novel flexible ionizing radiation sensors.
In addition, we have also investigated the ability of OSSCs to be employed as detectors of other ionizing radiations. The proof of principle of alpha particles detection has been assessed and pulse- height analysis has been performed for 4HCB single crystals, both in planar and vertical electrode configurations, extracting Charge Collection Efficiency (CCE) and performing the first time-of-flight (TOF) experiment in organic materials by means of alpha particles radiation.