Passivation is an important process that reduces surface leakage current and its attendant noise. We treated detector-grade large-volume CdMnTe:In samples with an (NH 4)-based passivant, and compared the results with untreated samples by measuring current-voltage characteristics, surface recombination velocity, Raman spectroscopy, and charge-collection mapping. The leakage current of the passivated CdMnTe (CMT) detectors decreased five to ten times, and surface recombination declined five to six times, depending on the passivation conditions applied. We satisfactorily explained these improvements in detector performance as resulting from different passivation layers that were generated by distinct chemical reactions, as determined by the pH of the passivant.
Bibliographical noteFunding Information:
This work was supported by the U.S. Department of Energy, Office of Nonproliferation Research and Development, NA-22. The manuscript has been authored by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH1-886 with the U.S. Department of Energy. Also, research carried out in part at the Center for Functional Nano-materials, Brookhaven National Laboratory, which is supported by the U.S. Department of Energy, Office of Basic Energy Sciences, under Contract No. DE-AC02-98CH10886.
- Ammonium fluoride
- Ammonium sulfide
- Charge-collection efficiency
- Leakage current
- Surface recombination
- Tellurium oxide
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering
- Materials Chemistry