Temperature dependence of the fast, near-band-edge scintillation from CuI, HgI2, PbI2, ZnO:Ga, and CdS:In

Journal Article · Fri Sep 07 04:00:00 EDT 2001 · Nuclear Instruments and Methods

OSTI ID:837912

Derenzo, Stephen E ^[1]; Weber, Marvin J; Klintenberg, Mattias K

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1. LBNL Library

We present temperature-dependent pulsed x-ray data on the decay time spectra, wavelengths, and intensities of fast (ns) radiative recombination in five direct, wide-bandgap semiconductors: CuI, HgI2, PbI2, and n-doped ZnO:Ga and CdS:In. At 12K the luminosity of powder samples is 0.30, 1.6, 0.40, 2.0, and 0.15, respectively, relative to that of BGO powder at room temperature. Increasing the temperature of CuI to 346K decreases the luminosity by a factor of 300 while decreasing the fwhm of the decay time spectra from 0.20 ns to 0.11 ns. Increasing the temperature of HgI2 to 102K decreases the luminosity by a factor of 53 while decreasing the fwhm from 1.6 ns to 0.5 ns. Increasing the temperature of PbI2 to 165K decreases the luminosity by a factor of 27 while decreasing the fwhm from 0.52 ns to 0.15 ns. Increasing the temperature of ZnO:Ga to 365K decreases the luminosity by a factor of 33 while decreasing the fwhm from 0.41 ns to 0.21 ns. Increasing the temperature of CdS:In to 295K decreases the luminosity by a factor of 30 while decreasing the fwhm from 0.20 ns to 0.17 ns. All emission wavelengths are near the band edge. The luminosities decrease much faster than the radiative lifetimes, therefore the reduction in luminosity is not primarily due to thermal quenching of the excited states but mostly due to thermally activated trapping charge carriers on nonradiative recombination centers. Since the radiative and nonradiative processes occur on different centers, increasing the ratio of radiative to nonradiative centers could result in a class of inorganic scintillators whose decay time and radiative efficiency would approach fundamental limits (i.e., <1 ns and 100,000 photons per MeV).

• Research Organization: Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, CA (US)
• Sponsoring Organization: USDOE Director, Office of Science. Office of Biological and Environmental Research. Medical Sciences Division; National Institutes of Health (US)
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 837912
• Report Number(s): LBNL--49282
• Journal Information: Nuclear Instruments and Methods, Journal Name: Nuclear Instruments and Methods Journal Issue: 1-2 Vol. 486; ISSN NUIMAL; ISSN 0029-554X
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
74 ATOMIC AND MOLECULAR PHYSICS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
CHARGE CARRIERS
DECAY
EFFICIENCY
EXCITED STATES
LUMINOSITY
PHOSPHORS
PHOTONS
QUENCHING
RECOMBINATION
SCINTILLATIONS
SMICONDUCTOR SCINTILLATOR DETECTOR
SPECTRA
TEMPERATURE DEPENDENCE
TRAPPING
WAVELENGTHS