Long-term stability of ammonium-sulfide- and ammonium-fluoride-passivated CdMnTe detectors

Abstract

We evaluated the long-term stability of CdMnTe (CMT) detectors treated with ammonium-saltbased passivants. Passivation improved the detector's stability and reduced the degradation of its energy resolution with time. Here, we stored passivated 5 × 5 × 9 mm 3 CMT detectors in an ambient environment for 550 days and evaluated the effects of aging by measuring their pulse-height spectra over time. The CMT detector passivated with ammonium fluoride exhibited a higher leakage current after 550 days, and its performance was degraded accordingly. Our analyses of the leakage current for a pixelated CMT detector revealed that the edges and the corners of the detector were responsible for the higher leakage, which resulted from a degradation of the passivation layer in those areas. Assurance of the long-term stability and reproducibility of the detector necessitates that the edges and the corners be mechanically passivated following chemical treatment.

Ab initio GGA+U investigations of the structural, electronic, and magnetic properties of Cd1-xMnxTe alloy

“…In particular, a large sp-d exchange interaction between the charge carriers and the magnetic ions leads to strong band splitting in Cd1-xMnxTe crystals, which results in the giant Faraday rotation and Zeeman splitting [1,6]. Recently, Cd1-xMnxTe alloy was proposed as a material for nuclear radiation detectors [7,8] due to its good electron transport properties and high resistivity [9,10].…”