Carbon Coating and Defects in CdZnTe and CdMnTe Nuclear Detectors

Stephen U. Egarievwe, Wing Chan, Ki Hyun Kim, Utpal N. Roy, Valissa Sams, Anwar Hossain, Aschalew Kassu, Ralph B. James

Research output: Contribution to journalArticlepeer-review

21 Citations (Scopus)


CADMIUM zinc telluride (CdZnTe) and cadmium manganese telluride (CdMnTe) are prime materials for detecting X-rays and gamma-rays at room temperature due to their high average atomic numbers that are essential to having high stopping-power for incident high-energy electromagnetic radiations. A major obstacle in developing CdZnTe and CdMnTe detectors lies in growing crystals free from defects, such as Te inclusions, dislocations, sub-grain boundary networks, and precipitates. We present the results of our study of the relationship between carbon coating of the growth ampoule and dislocations in CdZnTe and sub-grain boundary networks in CdMnTe, grown by Bridgman method. For the CdZnTe crystals, a carbon-coating of 2μm on the ampoule generated fewer dislocations than did a thinner 0.2 -μm carbon-coated one. Furthermore, the ampoule's design (normal- or tapered-shape) did not affect the densities of etch pits as much as did the thickness of the carbon-coating. For a CdMnTe ingot with a carbon coating of about 2μm, created by cracking spectroscopic-grade acetone at ∼900°C, we observed very few grain boundaries and grain-boundary networks.

Original languageEnglish
Article number7407494
Pages (from-to)236-245
Number of pages10
JournalIEEE Transactions on Nuclear Science
Issue number1
Publication statusPublished - 2016 Feb 1


  • Bridgman crystal growth
  • CdMnTe
  • CdZnTe
  • dislocations
  • etch-pit densities
  • gamma-ray detectors
  • growth ampoules
  • sub-grain boundary network

ASJC Scopus subject areas

  • Nuclear and High Energy Physics
  • Nuclear Energy and Engineering
  • Electrical and Electronic Engineering


Dive into the research topics of 'Carbon Coating and Defects in CdZnTe and CdMnTe Nuclear Detectors'. Together they form a unique fingerprint.

Cite this