Journal of Electronic Materials

, Volume 35, Issue 6, pp 1251–1256

Simulation, modeling, and crystal growth of Cd0.9Zn0.1Te for nuclear spectrometers

  • Krishna C. Mandal
  • Sung Hoon Kang
  • Michael Choi
  • Job Bello
  • Lili Zheng
  • Hui Zhang
  • Michael Groza
  • Utpal N. Roy
  • Arnold Burger
  • Gerald E. Jellison
  • David E. Holcomb
  • Gomez W. Wright
  • Joseph A. Williams
Article

DOI: 10.1007/s11664-006-0250-6

Cite this article as:
Mandal, K.C., Kang, S.H., Choi, M. et al. Journal of Elec Materi (2006) 35: 1251. doi:10.1007/s11664-006-0250-6

Abstract

High-quality, large (10 cm long and 2.5 cm diameter), nuclear spectrometer grade Cd0.9Zn0.1Te (CZT) single crystals have been grown by a controlled vertical Bridgman technique using in-house zone refined precursor materials (Cd, Zn, and Te). A state-of-the-art computer model, multizone adaptive scheme for transport and phase-change processes (MASTRAP), is used to model heat and mass transfer in the Bridgman growth system and to predict the stress distribution in the as-grown CZT crystal and optimize the thermal profile. The model accounts for heat transfer in the multiphase system, convection in the melt, and interface dynamics. The grown semi-insulating (SI) CZT crystals have demonstrated promising results for high-resolution room-temperature radiation detectors due to their high dark resistivity (ρ≈2.8 × 1011 Θ cm), good charge-transport properties [electron and hole mobility-life-time product, μτe≈(2–5)×10−3 and μτh≈(3–5)×10−5 respectively, and low cost of production. Spectroscopic ellipsometry and optical transmission measurements were carried out on the grown CZT crystals using two-modulator generalized ellipsometry (2-MGE). The refractive index n and extinction coefficient k were determined by mathematically eliminating the ∼3-nm surface roughness layer. Nuclear detection measurements on the single-element CZT detectors with 241Am and 137Cs clearly detected 59.6 and 662 keV energies with energy resolution (FWHM) of 2.4 keV (4.0%) and 9.2 keV (1.4%), respectively.

Key words

CZTMASTRAP modelBridgman technique2-MGEradiation detectors

Copyright information

© TMS-The Minerals, Metals and Materials Society 2006

Authors and Affiliations

  • Krishna C. Mandal
    • 1
  • Sung Hoon Kang
    • 1
  • Michael Choi
    • 1
  • Job Bello
    • 1
  • Lili Zheng
    • 2
  • Hui Zhang
    • 2
  • Michael Groza
    • 3
  • Utpal N. Roy
    • 3
  • Arnold Burger
    • 3
  • Gerald E. Jellison
    • 4
  • David E. Holcomb
    • 4
  • Gomez W. Wright
    • 4
  • Joseph A. Williams
    • 4
  1. 1.EIC Laboratories, Inc.Norwood
  2. 2.Department of Mechanical EngineeringState University of New York at Stony BrookStony Brook
  3. 3.Center of Excellence in Physics and Chemistry of MaterialsFisk UniversityNashville
  4. 4.Oak Ridge National LaboratoryOak Ridge