Electrodrift purification of materials for room temperature radiation detectors
Abstract
A method of purifying nonmetallic, crystalline semiconducting materials useful for room temperature radiation detecting devices by applying an electric field across the material is disclosed. The present invention discloses a simple technology for producing purified ionic semiconducting materials, in particular PbI{sub 2} and preferably HgI{sub 2}, which produces high yields of purified product, requires minimal handling of the material thereby reducing the possibility of introducing or reintroducing impurities into the material, is easy to control, is highly selective for impurities, retains the stoichiometry of the material and employs neither high temperatures nor hazardous materials such as solvents or liquid metals. An electric field is applied to a bulk sample of the material causing impurities present in the sample to drift in a preferred direction. After all of the impurities have been transported to the ends of the sample the current flowing through the sample, a measure of the rate of transport of mobile impurities, falls to a low, steady state value, at which time the end sections of the sample where the impurities have concentrated are removed leaving a bulk sample of higher purity material. Because the method disclosed here only acts on the electrically active impurities, the stoichiometry ofmore »
- Inventors:
- Issue Date:
- Research Org.:
- Sandia National Laboratories (SNL), Albuquerque, NM, and Livermore, CA (United States)
- Sponsoring Org.:
- USDOE, Washington, DC (United States)
- OSTI Identifier:
- 512438
- Patent Number(s):
- 5641392
- Application Number:
- PAN: 8-504,001
- Assignee:
- SNL; SCA: 440000; 360601; PA: EDB-97:112912; SN: 97001827932
- DOE Contract Number:
- AC04-94AL85000
- Resource Type:
- Patent
- Resource Relation:
- Other Information: PBD: 24 Jun 1997
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 44 INSTRUMENTATION, INCLUDING NUCLEAR AND PARTICLE DETECTORS; 36 MATERIALS SCIENCE; SEMICONDUCTOR MATERIALS; SEMICONDUCTOR DETECTORS; MERCURY IODIDES; LEAD IODIDES; AMBIENT TEMPERATURE; ELECTRIC FIELDS; FABRICATION; PURIFICATION
Citation Formats
James, R B, Van Scyoc, III, J M, and Schlesinger, T E. Electrodrift purification of materials for room temperature radiation detectors. United States: N. p., 1997.
Web.
James, R B, Van Scyoc, III, J M, & Schlesinger, T E. Electrodrift purification of materials for room temperature radiation detectors. United States.
James, R B, Van Scyoc, III, J M, and Schlesinger, T E. Tue .
"Electrodrift purification of materials for room temperature radiation detectors". United States.
@article{osti_512438,
title = {Electrodrift purification of materials for room temperature radiation detectors},
author = {James, R B and Van Scyoc, III, J M and Schlesinger, T E},
abstractNote = {A method of purifying nonmetallic, crystalline semiconducting materials useful for room temperature radiation detecting devices by applying an electric field across the material is disclosed. The present invention discloses a simple technology for producing purified ionic semiconducting materials, in particular PbI{sub 2} and preferably HgI{sub 2}, which produces high yields of purified product, requires minimal handling of the material thereby reducing the possibility of introducing or reintroducing impurities into the material, is easy to control, is highly selective for impurities, retains the stoichiometry of the material and employs neither high temperatures nor hazardous materials such as solvents or liquid metals. An electric field is applied to a bulk sample of the material causing impurities present in the sample to drift in a preferred direction. After all of the impurities have been transported to the ends of the sample the current flowing through the sample, a measure of the rate of transport of mobile impurities, falls to a low, steady state value, at which time the end sections of the sample where the impurities have concentrated are removed leaving a bulk sample of higher purity material. Because the method disclosed here only acts on the electrically active impurities, the stoichiometry of the host material remains substantially unaffected. 4 figs.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1997},
month = {6}
}