X-ray characterization of CMOS imaging detector with high resolution for fluoroscopic imaging application

This paper introduces complementary metal-oxide semiconductor (CMOS) active pixel sensor (APS)-based X-ray imaging detectors with high spatial resolution for medical imaging application. In this study, our proposed X-ray CMOS imaging sensor has been fabricated by using a 0.35 pm 1 Poly 4 Metal CMOS process. The pixel size is 100 mu m x 100 mu m and the pixel array format is 24 x 96 pixels, which provide a field-of-view (FOV) of 9.6 mm x 24 mm. The 14.3-bit extend counting analog-to digital converter (ADC) with built-in binning mode was used to reduce the area and simultaneously improve the image resolution. Both thallium-doped Cs! (Cst:TI) and Gd2O2S:Tb scintillator screens were used as converters for incident X-rays to visible light photons. The optical property and X-ray imaging characterization such as X-ray to light response as a function of incident X-ray exposure dose, spatial resolution and X-ray images of objects were measured under different X-ray energy conditions. The measured results suggest that our developed CMOS-based X-ray imaging detector has the potential for fluoroscopic imaging and cone-beam computed tomography (CBCT) imaging applications. (C) 2013 Elsevier B.V. All rights rescrved.This research was supported by research project of Korea Electrotechnology Research Institute (KERI) funded by the Ministry of Knowledge Economy