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Title: FY06 Annual Report: Amorphous Semiconductors for Gamma Radiation Detection (ASGRAD)

Abstract

We describe progress in the development of new materials for portable, room-temperature, gamma-radiation detection at Pacific Northwest National Laboratory at the Hanford Site in Washington State. High Z, high resistivity, amorphous semiconductors are being designed for use as solid-state detectors at near ambient temperatures; principles of operation are analogous to single-crystal semiconducting detectors. Amorphous semiconductors have both advantages and disadvantages compared to single crystals, and this project is developing methods to mitigate technical problems and design optimized material for gamma detection. Several issues involved in the fabrication of amorphous semiconductors are described, including reaction thermodynamics and kinetics, the development of pyrolytic coating, and the synthesis of ingots. The characterization of amorphous semiconductors is described, including sectioning and polishing protocols, optical microscopy, X-ray diffraction, scanning electron microscopy, optical spectroscopy, particle-induced X-ram emission, Rutherford backscattering, and electrical testing. Then collaboration with the University of Illinois at Urbana-Champaign is discussed in the areas of Hall-effect measurements and current voltage data. Finally, we discuss the strategy for continuing the program.

Authors:
; ; ; ; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
1047430
Report Number(s):
PNNL-16429
19197; NN2001000; TRN: US201216%%395
DOE Contract Number:
AC05-76RL01830
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; AMBIENT TEMPERATURE; BACKSCATTERING; DESIGN; DETECTION; ELECTRICAL TESTING; FABRICATION; GAMMA DETECTION; GAMMA RADIATION; HALL EFFECT; KINETICS; MONOCRYSTALS; OPTICAL MICROSCOPY; POLISHING; SCANNING ELECTRON MICROSCOPY; SPECTROSCOPY; SYNTHESIS; THERMODYNAMICS; X-RAY DIFFRACTION; gamma radiation detection; amorphous semiconductors; Environmental Molecular Sciences Laboratory

Citation Formats

Johnson, Bradley R., Riley, Brian J., Crum, Jarrod V., Sundaram, S. K., Henager, Charles H., Zhang, Yanwen, and Shutthanandan, V. FY06 Annual Report: Amorphous Semiconductors for Gamma Radiation Detection (ASGRAD). United States: N. p., 2007. Web. doi:10.2172/1047430.
Johnson, Bradley R., Riley, Brian J., Crum, Jarrod V., Sundaram, S. K., Henager, Charles H., Zhang, Yanwen, & Shutthanandan, V. FY06 Annual Report: Amorphous Semiconductors for Gamma Radiation Detection (ASGRAD). United States. doi:10.2172/1047430.
Johnson, Bradley R., Riley, Brian J., Crum, Jarrod V., Sundaram, S. K., Henager, Charles H., Zhang, Yanwen, and Shutthanandan, V. Mon . "FY06 Annual Report: Amorphous Semiconductors for Gamma Radiation Detection (ASGRAD)". United States. doi:10.2172/1047430. https://www.osti.gov/servlets/purl/1047430.
@article{osti_1047430,
title = {FY06 Annual Report: Amorphous Semiconductors for Gamma Radiation Detection (ASGRAD)},
author = {Johnson, Bradley R. and Riley, Brian J. and Crum, Jarrod V. and Sundaram, S. K. and Henager, Charles H. and Zhang, Yanwen and Shutthanandan, V.},
abstractNote = {We describe progress in the development of new materials for portable, room-temperature, gamma-radiation detection at Pacific Northwest National Laboratory at the Hanford Site in Washington State. High Z, high resistivity, amorphous semiconductors are being designed for use as solid-state detectors at near ambient temperatures; principles of operation are analogous to single-crystal semiconducting detectors. Amorphous semiconductors have both advantages and disadvantages compared to single crystals, and this project is developing methods to mitigate technical problems and design optimized material for gamma detection. Several issues involved in the fabrication of amorphous semiconductors are described, including reaction thermodynamics and kinetics, the development of pyrolytic coating, and the synthesis of ingots. The characterization of amorphous semiconductors is described, including sectioning and polishing protocols, optical microscopy, X-ray diffraction, scanning electron microscopy, optical spectroscopy, particle-induced X-ram emission, Rutherford backscattering, and electrical testing. Then collaboration with the University of Illinois at Urbana-Champaign is discussed in the areas of Hall-effect measurements and current voltage data. Finally, we discuss the strategy for continuing the program.},
doi = {10.2172/1047430},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}

Technical Report:

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  • The general purpose of this work has been to clarify the steady-state photoelectronic properties of amorphous hydrogenated silicon and related semiconductors, and to contribute to understanding the underlying electronic band structure. The first phase of this work concentrated on transient phototransport measured on samples of doped and undoped a-Si:H. In the second year of this contract, we have concentrated on the examination of the possibility of investigating the doping of a-Si:H by P through neutron transmutation doping, examination of the theory of photoluminescence, completion of a study on the effect of carrier loss to deep traps during dispersive transport, andmore » an experimental study of optical absorption involving states near mid-gap, caused by carrier injection at contacts.« less
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