Title :
Analysis of lead oxide (PbO) layers for direct conversion X-ray detection
Author :
Simon, M. ; Ford, R.A. ; Franklin, A.R. ; Grabowski, S.P. ; Menser, B. ; Much, G. ; Nascetti, A. ; Overdick, M. ; Powell, M.J. ; Wiechert, D.U.
Author_Institution :
Philips Res. Labs., Aachen, Germany
Abstract :
Lead oxide (PbO) is a candidate direct conversion material for medical X-ray applications. We produced various samples and detectors with thick PbO layers. X-ray performance data such as dark current, charge generation yield and temporal behavior were evaluated on small samples. The influence of the metal contacts was studied in detail. We also covered large a-Si thin-film transistor (TFT)-plates with PbO. Imaging results from a large detector with an active area of 18 cm × 20 cm are presented. The detector has 960 × 1080 pixels with a pixel pitch of 184 μm. The modulation transfer function at the Nyquist frequency of 2.72 linepairs/mm is 50%. Finally, a full size X-ray image is presented.
Keywords :
X-ray detection; X-ray imaging; dark conductivity; electrical contacts; optical transfer function; thin film transistors; Nyquist frequency; PbO; TFT-plates; X-ray image; a-Si thin-film transistor; charge generation; dark current; detective quantum efficiency; direct conversion X-ray detection; lead oxide layers; medical X-ray applications; metal contacts; modulation transfer function; pixel pitch; temporal behavior; Biomedical imaging; Dark current; Detectors; Lead compounds; Optical imaging; Thin film transistors; Transfer functions; X-ray applications; X-ray detection; X-ray imaging; Contacts; PbO; X-ray detector; detective quantum efficiency; direct detection; lead oxide;
Journal_Title :
Nuclear Science, IEEE Transactions on
DOI :
10.1109/TNS.2005.856790
