A New X-Ray Spectroscopy Concept-Room Temperature Mercuric Iodide with Peltier-Cooled Preamplification

Abstract

Mercuric iodide (HgI2) with high atomic numbers of 80 and 53 for the components, and wide bandgap (2.1 eV) has been considered a potentially useful material for gamma ray spectroscopy for the last number of years. Considerable effort by numerous groups has been directed toward purification and growth of large single crystals of this material. Even with continuing improvement, however, the material is still characterized by good electron transport properties and only modest to poor hole transport behavior. Interesting results nevertheless have been reported in mid-range gamma ray spectroscopy using “up to millimeter thick sections of HgI2. One question always asked is: has the fundamental of lattice scattering etc. been reached in increasing hole transport behavior in this material? There is interesting speculation at this time that this may not be so.