Thick films of X-ray polycrystalline mercuric iodide detectors

Polycrystalline HgI2 thick film detectors are among the leading semiconduct or materials to be used as direct converters in X-ray digital radiography. Their properties along with a survey of the properties of alternative mater ials, such as PbI2 or A-Se, will be given. The preparation of HgI detector plates, both by direct evaporation (Physical vapor deposition, (PVD)) and b y binding the individual crystallites with polymeric glue, forming screen-p rinted (SP) detector plates, will be described. The microstructure of the P VD thick films showing a columnar morphology, as determined by SEM measurem ents, will be shown. The X-ray response to radiological X-ray generator of 85 kVp using the current integration mode will be reported for both PVD and SP films. Finally, some X-ray images taken at Xerox-Parc using HgI, polycr ystalline detectors will be shown. (C) 2001 Elsevier Science B.V. All right s reserved.