Purification of HgI2 Crystals from Physical Vapor Transport for Application as Radiation Detectors

The establishment of a technique for mercury iodide (HgI2) purification and crystal growth is described, aiming this crystal future application as room temperature radiation semiconductor detectors. Repeated Physical Vapor Transport (PVT) technique was studied for purification and growth of the crystal. To evaluate the purification efficiency, measurements of the impurity concentration were made after each growth, analyzing the trace impurities. A significant decrease of the impurity concentration, resulting from the purification number, was observed. A significant improvement in the HgI2 radiation detector performance was achieved for purer crystals, growing the crystal twice by the PVT technique.