Towards Low-Voltage and Bendable X-ray Direct Detectors Based on Organic Semiconducting Single Crystals

Solution-grown organic semiconducting single crystals are robust and easy to handle materials that can reliably detect X-rays in the direct approach, operating at room temperature and in air, providing a linear response to increasing X-ray dose rates. Crystals only a few tens of micrometers thick thus grant a full photogenerated charge collection and this opens the possibility to integrate radiation detectors based on organic crystals into bendable and potentially even flexible electronic devices, exploiting the enhanced fl exibility of thin crystals and the recently reported possibility to cover large areas with inkjet printed single crystalline thin films. Device geometries that maximize the electrode/semiconductor interface active area allow to significantly increase the charge collection efficiency and the X-ray electrical photoresponse of 4HCB single crystals. The reported sensitivity of 4HCB-based detectors is in line with that of state-of-the-art a-Se based detectors.