Title :
HgI2 polycrystalline films for digital X-ray imagers
Author :
Iwanczyk, J.S. ; Patt, B.E. ; Tull, C.R. ; MacDonald, L.R. ; Skinner, N. ; Hoffman, E.J. ; Fornaro, L.
Author_Institution :
Photon Imaging, Inc., Northridge, CA, USA
fDate :
2/1/2002 12:00:00 AM
Abstract :
This paper describes recent results obtained with mercuric iodide (HgI2) polycrystalline films that we have produced. The ultimate goal of this effort is to develop a new detector technology for digital X-ray imaging based on HgI2 polycrystalline films coupled to large-area flat-panel amorphous silicon thin-film transistor-addressed readout arrays. We have employed two approaches for producing the polycrystalline films: 1) thermal evaporation (sublimation) and 2) deposition of films from various solutions. The 50- to 150-μm-thick films were characterized with respect to their electrical properties and in response to ionizing radiation. The leakage current was about 40 pA/cm2 at an operating bias voltage of ~50 V. Signals from the HgI2 polycrystalline detectors, in response to ionizing radiation, compare favorably to the best published results for all high Z polycrystalline films grown elsewhere, including TlBr, PbI2, and HgI2
Keywords :
X-ray detection; X-ray imaging; dark conductivity; leakage currents; liquid phase deposition; mercury compounds; semiconductor growth; semiconductor materials; sublimation; thin films; vacuum deposition; 50 V; 50 to 150 micron; HgI2; HgI2 polycrystalline films; bias voltage; detector technology; digital X-ray imaging; electrical properties; film thickness; ionizing radiation response; large-area flat-panel a-Si TFT-addressed readout arrays; leakage current; solution deposition; sublimation; thermal evaporation; Amorphous silicon; Ionizing radiation; Leakage current; Semiconductor films; Semiconductor thin films; Sensor arrays; Thin film transistors; X-ray detection; X-ray detectors; X-ray imaging;
Journal_Title :
Nuclear Science, IEEE Transactions on
DOI :
10.1109/TNS.2002.998745
