Title :
Low noise, large area CMOS x-ray image sensor for C.T. application
Author :
Kemna, A. ; Brockherde, W. ; Hosticka, B. ; Özkan, E. ; Morales-Serrano, F. ; Steadman, R. ; Vogtmeier, G.
Author_Institution :
Fraunhofer Inst. for. Microelectron. Circuits & Syst., Duisburg, Germany
Abstract :
In this paper, we describe a novel CMOS X-ray active pixel sensor for indirect C.T. X-ray detection. Considerable noise reduction has been achieved by lowering the detector junction capacitance. For this purpose a new low capacitance, low dark current dot type photodiode based on minority diffusion has been developed. The dynamic range is expanded to 17 bit by the use of individual in-pixel automatic gain control. A photon noise limited detector exhibiting a 20 × 10 pixel array with a frame rate of 3000 frames/sec has been realized in a 1.2 μm CMOS process.
Keywords :
CMOS image sensors; X-ray detection; computerised tomography; photodiodes; 1.2 micron; X-ray detection; computer tomography; detector junction capacitance; in-pixel automatic gain control; low capacitance; low dark current dot type photodiode; low noise large area CMOS x-ray image sensor; minority diffusion; noise reduction; photon noise limited detector; CMOS image sensors; Capacitance; Dark current; Detectors; Image sensors; Noise reduction; Photodiodes; Sensor phenomena and characterization; X-ray detection; X-ray imaging;
Conference_Titel :
Sensors, 2003. Proceedings of IEEE
Print_ISBN :
0-7803-8133-5
DOI :
10.1109/ICSENS.2003.1279147
