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http://dx.doi.org/10.4313/TEEM.2004.5.4.133

X-ray Sensitivity of Hybrid-type Sensor based on CaWO4-Selenium for Digital X-ray Imager  

Park, Ji-Koon (Department of Biomedical Engineering, College of Biomedical Science and Engineering, Inje University)
Park, Jang-Yong (Department of Biomedical Engineering, College of Biomedical Science and Engineering, Inje University)
Kang, Sang-Sik (Department of Biomedical Engineering, College of Biomedical Science and Engineering, Inje University)
Lee, Dong-Gil (Department of Biomedical Engineering, College of Biomedical Science and Engineering, Inje University)
Kim, Jae-Hyung (Medical Imaging Research Center, Inje University)
Nam, Sang-Hee (Medical Imaging Research Center, Inje University)
Publication Information
Transactions on Electrical and Electronic Materials / v.5, no.4, 2004 , pp. 133-137 More about this Journal
Abstract
The development of digital x-ray detector has been extensively progressed for the application of various medical modalities. In this study, we introduce a new hybrid-type x-ray detector to improve problems of a conventional direct or indirect digital x-ray image technology, which composed of multi-layer structure using a CaWO$_4$ phosphor and amorphous selenium (a-Se) photoconductor. The leakage current of our detector was found to be ∼180 pA/cm$^2$ at 10 V/m, which was significantly reduced than that of a single a-Se detector. The x-ray sensitivity was measured as the value of 4230 pC/cm$^2$/mR at 10 V/m. We found that the parylene thin film between a CaWO$_4$ phosphor and an a-Se layer acts as an insulator to prevent charge injection from indium thin oxide (ITO) electrode into an a-Se layer under applied bias.
Keywords
Amorphous selenium; Hybrid-type x-ray detector; Dark current; X-ray sensitivity;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
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