Comparative study of dislocation densities in CdZnTe ingots grown with different carbon coatings

Wing Chan, Valissa Sams, Kihyun Kim, Aschalew Kassu, Ralph James

Research output: Chapter in Book/Report/Conference proceedingConference contribution

2 Citations (Scopus)

Abstract

Cadmium Zinc Telluride (CdZnTe) is known to be one of the best room temperature X-ray and gamma-ray radiation detector's materials. However, the supply of high-quality CdZnTe detectors is limited due to crystal defects such as dislocations, impurities, Te inclusions that are generated during the crystal growth process. Dislocations are generated due to the stress/strain in the growth process. In this study, we characterized dislocation densities in CdZnTe crystals grown by different techniques (i.e. different carbon-coating thickness and ampoule's shapes) for the suggestion of better growth techniques. Dislocations densities were revealed using a Saucedo solution and analyzed by an infrared microscope. The thick carbon-coated ampoules generated fewer dislocations than the thin carbon-coated ampoule and the ampoule design did not affect the etch pit densities (EPD) as much than carbon-coating thickness. Also, we concluded that a proper crystal growth rate and cooling down rate is one important factor in minimizing dislocations in CdZnTe crystals. The effects of dislocations on the CdZnTe detector's performance was evaluated from the 241Am gamma-response, which fabricated from low and high densities of etch pit region.

Original languageEnglish
Title of host publication2012 IEEE Nuclear Science Symposium and Medical Imaging Conference Record, NSS/MIC 2012
Pages4241-4244
Number of pages4
DOIs
Publication statusPublished - 2012 Dec 1
Event2012 IEEE Nuclear Science Symposium and Medical Imaging Conference Record, NSS/MIC 2012 - Anaheim, CA, United States
Duration: 2012 Oct 292012 Nov 3

Publication series

NameIEEE Nuclear Science Symposium Conference Record
ISSN (Print)1095-7863

Other

Other2012 IEEE Nuclear Science Symposium and Medical Imaging Conference Record, NSS/MIC 2012
CountryUnited States
CityAnaheim, CA
Period12/10/2912/11/3

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Keywords

  • ampoule's shape
  • carbon-coating thickness
  • CdZnTe
  • dislocations
  • etch-pit densities

ASJC Scopus subject areas

  • Radiation
  • Nuclear and High Energy Physics
  • Radiology Nuclear Medicine and imaging

Cite this

Chan, W., Sams, V., Kim, K., Kassu, A., & James, R. (2012). Comparative study of dislocation densities in CdZnTe ingots grown with different carbon coatings. In 2012 IEEE Nuclear Science Symposium and Medical Imaging Conference Record, NSS/MIC 2012 (pp. 4241-4244). [6551967] (IEEE Nuclear Science Symposium Conference Record). https://doi.org/10.1109/NSSMIC.2012.6551967