Measurement of PuO2 film thickness by electron probe microanalysis (EPMA) calibration curve method
Abstract
Plutonium (Pu) surfaces are highly reactive toward oxygen containing species and, therefore, invariably covered with oxides (e.g. PuO2) during transport and handling. The actual thickness of the surface oxide may dictate if a plutonium part is suitable for a certain application. As a result, a cost-effective, quick, non-destructive, yet reliable means to measure the oxide layer thickness formed on Pu samples is desirable. In this study, the cross-sections of a series of room temperature grown oxides on Pu samples were trenched by focus ion beam (FIB) then observed by scanning electron microscopy (SEM) to measure the surface oxide thicknesses, which were then combined with the corresponding oxygen k-ratios provided by electron probe microanalysis (EPMA) to form calibration curves. Oxide thickness measurements for the calibration curves were made on samples within the typical SEM observable range for PuO2 (35–400 nm). The portion of the calibration curve in the thinner oxide region (<35 nm) were approximated via Pouchou and Pichoir’s Φ(ρz) theory. Two specimens with micrometer-thick PuO2 standards (one formed at room temperature and the other at higher temperature with a higher level of crystallinity) were made for the k-ratios in this study, allowing EPMA users to choose the standard that bestmore »
- Authors:
-
- Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
- Publication Date:
- Research Org.:
- Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
- Sponsoring Org.:
- USDOE National Nuclear Security Administration (NNSA)
- OSTI Identifier:
- 1597211
- Alternate Identifier(s):
- OSTI ID: 1581010
- Report Number(s):
- LLNL-JRNL-791483
Journal ID: ISSN 0022-3115; 990598; TRN: US2103785
- Grant/Contract Number:
- AC52-07NA27344
- Resource Type:
- Accepted Manuscript
- Journal Name:
- Journal of Nuclear Materials
- Additional Journal Information:
- Journal Volume: 530; Journal Issue: C; Journal ID: ISSN 0022-3115
- Publisher:
- Elsevier
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 36 MATERIALS SCIENCE
Citation Formats
Stanford, J. A., Teslich, N., Donald, S., Saw, C. K., Gollott, R., and Dinh, L. N.. Measurement of PuO2 film thickness by electron probe microanalysis (EPMA) calibration curve method. United States: N. p., 2019.
Web. doi:10.1016/j.jnucmat.2019.151968.
Stanford, J. A., Teslich, N., Donald, S., Saw, C. K., Gollott, R., & Dinh, L. N.. Measurement of PuO2 film thickness by electron probe microanalysis (EPMA) calibration curve method. United States. https://doi.org/10.1016/j.jnucmat.2019.151968
Stanford, J. A., Teslich, N., Donald, S., Saw, C. K., Gollott, R., and Dinh, L. N.. Sat .
"Measurement of PuO2 film thickness by electron probe microanalysis (EPMA) calibration curve method". United States. https://doi.org/10.1016/j.jnucmat.2019.151968. https://www.osti.gov/servlets/purl/1597211.
@article{osti_1597211,
title = {Measurement of PuO2 film thickness by electron probe microanalysis (EPMA) calibration curve method},
author = {Stanford, J. A. and Teslich, N. and Donald, S. and Saw, C. K. and Gollott, R. and Dinh, L. N.},
abstractNote = {Plutonium (Pu) surfaces are highly reactive toward oxygen containing species and, therefore, invariably covered with oxides (e.g. PuO2) during transport and handling. The actual thickness of the surface oxide may dictate if a plutonium part is suitable for a certain application. As a result, a cost-effective, quick, non-destructive, yet reliable means to measure the oxide layer thickness formed on Pu samples is desirable. In this study, the cross-sections of a series of room temperature grown oxides on Pu samples were trenched by focus ion beam (FIB) then observed by scanning electron microscopy (SEM) to measure the surface oxide thicknesses, which were then combined with the corresponding oxygen k-ratios provided by electron probe microanalysis (EPMA) to form calibration curves. Oxide thickness measurements for the calibration curves were made on samples within the typical SEM observable range for PuO2 (35–400 nm). The portion of the calibration curve in the thinner oxide region (<35 nm) were approximated via Pouchou and Pichoir’s Φ(ρz) theory. Two specimens with micrometer-thick PuO2 standards (one formed at room temperature and the other at higher temperature with a higher level of crystallinity) were made for the k-ratios in this study, allowing EPMA users to choose the standard that best suits their needs. If the surface corrosion is known to be PuO2 (from the environment in which the Pu sample is stored) or if the stoichiometry of the surface oxide is confirmed by a preliminary/compliment technique, these calibration curves allow EPMA users to quickly and efficiently determine PuO2 thicknesses from the measured oxygen k-ratios of their samples. The methodology presented in this study can also be used as a template for creating calibration curves for oxides grown on other actinides.},
doi = {10.1016/j.jnucmat.2019.151968},
journal = {Journal of Nuclear Materials},
number = C,
volume = 530,
place = {United States},
year = {2019},
month = {12}
}
Web of Science
Works referenced in this record:
Oxidation kinetics of plutonium in air: consequences for environmental dispersal
journal, June 1998
- Haschke, John M.; Allen, Thomas H.; Martz, Joseph C.
- Journal of Alloys and Compounds, Vol. 271-273
Measuring the Thickness of Native Plutonium Oxides Using EPMA
journal, August 2005
- Nothwang, T.; Davis, C. C.; Lakis, R. E.
- Microscopy and Microanalysis, Vol. 11, Issue S02
Comparison of the sputter rates of oxide films relative to the sputter rate of SiO2
journal, September 2010
- Baer, D. R.; Engelhard, M. H.; Lea, A. S.
- Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films, Vol. 28, Issue 5
Electron Probe Microanalysis Through Coated Oxidized Surfaces
journal, July 2019
- Matthews, Mike B.; Buse, Ben; Kearns, Stuart L.
- Microscopy and Microanalysis, Vol. 25, Issue 05
Electron probe microanalysis (EPMA) measurement of aluminum oxide film thickness in the nanometer range on aluminum sheets
journal, January 2005
- Osada, Yoshio
- X-Ray Spectrometry, Vol. 34, Issue 2
Spectroscopic ellipsometry extraction of optical constants for materials from oxide covered samples: Application to the plutonium/oxides system
journal, May 2019
- Dinh, L. N.; Stanford, J. A.; Saw, C. K.
- Journal of Applied Physics, Vol. 125, Issue 18
Application of linear least squares to the analysis of Auger electron spectroscopy depth profiles of plutonium oxides
journal, May 2018
- Donald, Scott B.; Stanford, Jeff A.; McLean, William
- Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films, Vol. 36, Issue 3