Impurities Behaviors in Indium Iodide Materials

• Published in: IEEE transactions on nuclear science 2018-03, Vol.65 (3), p.909-912
• Main Authors: Leem, Sohee, Hwang, Seokjin, Yu, Hwanseung, Yoon, Yongsu, Kim, Kihyun
• Format: Article
• Language: English
• Subjects: Conductivity; Detectors; Electrical resistivity; Electron mobility; Impurities; Indium; Indium iodide (InI); Iodides; Ions; Mass spectroscopy; Materials selection; Pd/InI/Pd; pulse-height measurements; Radiation; Radiation detectors; Secondary ion mass spectroscopy; segregation coefficients; Sensors; Silicon; Temperature measurement; time-of-flight secondary ion mass spectroscopy (ToF-SIMS); zone refining
• ISSN: 0018-9499; 1558-1578
• DOI: 10.1109/TNS.2018.2796388

Environmentally friendly 99.998%-pure indium iodide (InI), one candidate materials for the room-temperature operating radiation detector, was purified more than 250 times using the zone-refining method to reduce the impurities. Segregation coefficient of major positive and negative impurities of the purified InI ingot was analyzed using time-of-flight secondary ion mass spectroscopy. Electrical and spectroscopic properties of the purified Pd/InI/Pd detector were also determined. Planar Pd/InI/Pd detector showed the 59.5-keV gamma peak of Am-241 clearly. However, low-energy gamma peaks were buried in the noise. Mechanical or electrical degradation under an ambient condition was not observed for six months. Electrical resistivity and electron mobility-lifetime product of the multiple-refined InI were 4\times 10^{11}\,\,\Omega \cdot \textrm {cm} and 1.3\times 10^{-3}\,\,\textrm {cm}^{2}/\textrm {V} , respectively.