Organic materials are receiving a large attention because of their potential application as low-cost, large-area electronic devices. In particular, the long-range molecular order of organic semiconducting single crystals (OSSCs) limits charge carrier trapping due to grain boundaries and structural imperfections that dominate electronic transport in polymers and organic thin films .Very little attention has been paid so far to the application of organic materials in direct charge based radiation detection. Most of the emphasis has currently centered on the development of organic scintillators or photodiodes for indirect radiation detectors [1,2]. We recently reported on the three-dimensional anisotropic charge transport properties of millimiter-sized solution-grown OSSCs based on a dipolar molecule 4HCB (4-hydroxy-cyanobenzene) [3]. In the present report we show how 4HCB single crystals can be reliably employed as room temperature solid state X-ray detectors with a linear response and a significant long-term stability, reproducibility and radiation hardness. The ease and low cost of OSSCs fabrication makes these devices quite appealing for future large-scale mass applications. Moreover, our findings demonstrate that the electronic spatial anisotropy of OSSCs, due to the intrinsic structural asymmetry of organic single crystals, has an effect on the macroscopic electronic device performance, thus paving the way to the development of novel electronic device architectures based on the simultaneous exploitation of the crystal different electronic responses along the three spatial directions of the crystal.
Organic semiconducting single crystals as room temperature radiation detectors
FRABONI, BEATRICE
2012
Abstract
Organic materials are receiving a large attention because of their potential application as low-cost, large-area electronic devices. In particular, the long-range molecular order of organic semiconducting single crystals (OSSCs) limits charge carrier trapping due to grain boundaries and structural imperfections that dominate electronic transport in polymers and organic thin films .Very little attention has been paid so far to the application of organic materials in direct charge based radiation detection. Most of the emphasis has currently centered on the development of organic scintillators or photodiodes for indirect radiation detectors [1,2]. We recently reported on the three-dimensional anisotropic charge transport properties of millimiter-sized solution-grown OSSCs based on a dipolar molecule 4HCB (4-hydroxy-cyanobenzene) [3]. In the present report we show how 4HCB single crystals can be reliably employed as room temperature solid state X-ray detectors with a linear response and a significant long-term stability, reproducibility and radiation hardness. The ease and low cost of OSSCs fabrication makes these devices quite appealing for future large-scale mass applications. Moreover, our findings demonstrate that the electronic spatial anisotropy of OSSCs, due to the intrinsic structural asymmetry of organic single crystals, has an effect on the macroscopic electronic device performance, thus paving the way to the development of novel electronic device architectures based on the simultaneous exploitation of the crystal different electronic responses along the three spatial directions of the crystal.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
