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Title: Synchrotron X-ray Based Characterization of CdZnTe Crystals

Abstract

Synthetic CdZnTe (CZT) crystals can be used for the room temperature-based detection of gamma radiation. Structural/morphological heterogeneities within CZT, such as secondary phases (namely, precipitates and inclusions), can negatively affect detector performance. We used a synchrotron-based x-ray technique, specifically extended x-ray absorption fine-structure (EXAFS) spectroscopy, to determine whether there are differences on a local structural level between intact CZT of high and low radiation detector performance. These studies were complemented by data on radiation detector performance and transmission infrared (IR) imaging. The EXAFS studies revealed no detectable local structural differences between the two types of CZT materials.

Authors:
; ; ; ; ; ; ;
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL) National Synchrotron Light Source
Sponsoring Org.:
Doe - Office Of Science
OSTI Identifier:
930039
Report Number(s):
BNL-80660-2008-JA
Journal ID: ISSN 0361-5235; JECMA5; TRN: US0806692
DOE Contract Number:
DE-AC02-98CH10886
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Electronic Materials; Journal Volume: 36; Journal Issue: 8
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; ABSORPTION SPECTROSCOPY; CRYSTALS; DETECTION; FINE STRUCTURE; GAMMA RADIATION; INCLUSIONS; INFRARED THERMOGRAPHY; LEVELS; MATERIALS; PERFORMANCE; RADIATION DETECTORS; SPECTROSCOPY; SYNCHROTRONS; X-RAY DIFFRACTION; national synchrotron light source

Citation Formats

Duff,M., Hunter, D., Nuessle, P., Black, D., Burdette, H., Woicik, J., Burger, A., and Groza, M. Synchrotron X-ray Based Characterization of CdZnTe Crystals. United States: N. p., 2007. Web. doi:10.1007/s11664-007-0181-x.
Duff,M., Hunter, D., Nuessle, P., Black, D., Burdette, H., Woicik, J., Burger, A., & Groza, M. Synchrotron X-ray Based Characterization of CdZnTe Crystals. United States. doi:10.1007/s11664-007-0181-x.
Duff,M., Hunter, D., Nuessle, P., Black, D., Burdette, H., Woicik, J., Burger, A., and Groza, M. Mon . "Synchrotron X-ray Based Characterization of CdZnTe Crystals". United States. doi:10.1007/s11664-007-0181-x.
@article{osti_930039,
title = {Synchrotron X-ray Based Characterization of CdZnTe Crystals},
author = {Duff,M. and Hunter, D. and Nuessle, P. and Black, D. and Burdette, H. and Woicik, J. and Burger, A. and Groza, M.},
abstractNote = {Synthetic CdZnTe (CZT) crystals can be used for the room temperature-based detection of gamma radiation. Structural/morphological heterogeneities within CZT, such as secondary phases (namely, precipitates and inclusions), can negatively affect detector performance. We used a synchrotron-based x-ray technique, specifically extended x-ray absorption fine-structure (EXAFS) spectroscopy, to determine whether there are differences on a local structural level between intact CZT of high and low radiation detector performance. These studies were complemented by data on radiation detector performance and transmission infrared (IR) imaging. The EXAFS studies revealed no detectable local structural differences between the two types of CZT materials.},
doi = {10.1007/s11664-007-0181-x},
journal = {Journal of Electronic Materials},
number = 8,
volume = 36,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
  • Synthetic CdZnTe or 'CZT' crystals can be used for the room temperature-based detection of {gamma}-radiation. Structural/morphological heterogeneities within CZT, such as twinning, inclusions, and polycrystallinity can affect detector performance. We used a synchrotron-based X-ray technique, specifically extended X-ray absorption fine-structure (EXAFS) spectroscopy, to determine whether there are differences on a local structural level between intact CZT of high and low radiation detector performance. These studies were complemented by data on radiation detector performance and transmission IR imaging. The EXAFS studies revealed no detectable local structural differences between the two types of CZT materials.
  • In a microgravity environment, gravity-dependent effects such as buoyancy, convection and hydrostatic pressure are minimized, providing an ideal environment for investigating diffusion-controlled, nonwetting crystal growth processes. To evaluate the influence of microgravity on the resultant crystal quality, Synchrotron White Beam X-ray Topography (SWBXT) is applied to characterize defect structures in both flight and ground-based CdZnTe single crystals. Transmission X-ray topographs recorded from one flight sample revealed regions of very low dislocation density with individual dislocations clearly resolved. Dislocations of very high density arrayed in a mosaic pattern were observed in all ground-base samples grown under identical growth conditions except formore » the gravity conditions. This observation indicates that the flight samples have much higher structural perfection than the ground-based samples. On the other hand, studies of defect configurations in a different flight sample revealed that structural defects and distributions can be strongly influenced by rapid cooling, thermal gradients, and constrained growth. Large thermal stresses induced by rapid cooling can be multiplied by wall contact leading to the formation of extensive slip bands and small angle tilt boundaries starting at the crystal periphery and propagating into the interior of the sample. It is concluded that an optimization of post solidification cooling rate is important to minimize the occurrence of slip.« less
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  • Future nanoelectronics manufacturing at extraordinary length scales, new device structures, and advanced materials will provide challenges to process development and engineering but also to process control and physical failure analysis. Advanced X-ray techniques, using lab systems and synchrotron radiation sources, will play a key role for the characterization of thin films, nanostructures, surfaces, and interfaces. The development of advanced X-ray techniques and tools will reduce risk and time for the introduction of new technologies. Eventually, time-to-market for new products will be reduced by the timely implementation of the best techniques for process development and process control. The development and usemore » of advanced methods at synchrotron radiation sources will be increasingly important, particularly for research and development in the field of advanced processes and new materials but also for the development of new X-ray components and procedures. The application of advanced X-ray techniques, in-line, in out-of-fab analytical labs and at synchrotron radiation sources, for research, development, and manufacturing in the nanoelectronics industry is reviewed. The focus of this paper is on the study of nanoscale device and on-chip interconnect materials, and materials for 3D IC integration as well.« less