Direct X-ray photoconversion in flexible organic thin film devices operated below 1?V.

ABSTRACT: The application of organic electronic materials for the detection of ionizing radiations is very appealing thanks to their mechanical flexibility, low-cost and simple processing in comparison to their inorganic counterpart. In this work we investigate the direct X-ray photoconversion process in organic thin film photoconductors. The devices are realized by drop casting solution-processed bis-(triisopropylsilylethynyl)pentacene (TIPS-pentacene) onto flexible plastic substrates patterned with metal electrodes; they exhibit a strong sensitivity to X-rays despite the low X-ray photon absorption typical of low-Z organic materials. We propose a model, based on the accumulation of photogenerated charges and photoconductive gain, able to describe the magnitude as well as the dynamics of the X-ray-induced photocurrent. This finding allows us to fabricate and test a flexible 2 × 2 pixelated X-ray detector operating at 0.2?V, with gain and sensitivity up to 4.7 × 10(4) and 77,000?nC?mGy(-1)?cm(-3), respectively.

SUBMITTER: Basirico L 

PROVIDER: S-EPMC5059709 | biostudies-other | 2016 Oct

REPOSITORIES: biostudies-other