Measuring Compositions in Organic Depth Profiling: Results from a VAMAS Interlaboratory Study

Citation

Shard, A. G.; Havelund, R.; Spencer, S. J.; Gilmore, I. S.; Alexander, M. R.; Angerer, T. B.; Aoyagi, S.; Barnes, J. P.; Benayad, A.; Bernasik, A.; Ceccone, G.; Counsell, J. D.; Deeks, C.; Fletcher, J. S.; Graham, D. J.; Heuser, C.; Lee, T. G.; Marie, C.; Marzec, M. M.; Mishra, G.; Rading, D.; Renault, O.; Scurr, D. J.; Shon, H. K.; Spampinato, V.; Tian, H.; Wang, F.; Winograd, N.; Wu, K.; Wucher, A.; Zhou, Y.; Zhu, Z.; Cristaudo, V.; & Poleunis, C. (2015). Measuring Compositions in Organic Depth Profiling: Results from a VAMAS Interlaboratory Study. J Phys Chem B, 119(33), 10784-10797.

Abstract

We report the results of a VAMAS (Versailles Project on Advanced Materials and Standards) interlaboratory study on the measurement of composition in organic depth profiling. Layered samples with known binary compositions of Irganox 1010 and either Irganox 1098 or Fmoc-pentafluoro-l-phenylalanine in each layer were manufactured in a single batch and distributed to more than 20 participating laboratories. The samples were analyzed using argon cluster ion sputtering and either X-ray photoelectron spectroscopy (XPS) or time-of-flight secondary ion mass spectrometry (ToF-SIMS) to generate depth profiles. Participants were asked to estimate the volume fractions in two of the layers and were provided with the compositions of all other layers. Participants using XPS provided volume fractions within 0.03 of the nominal values. Participants using ToF-SIMS either made no attempt, or used various methods that gave results ranging in error from 0.02 to over 0.10 in volume fraction, the latter representing a 50% relative error for a nominal volume fraction of 0.2. Error was predominantly caused by inadequacy in the ability to compensate for primary ion intensity variations and the matrix effect in SIMS. Matrix effects in these materials appear to be more pronounced as the number of atoms in both the primary analytical ion and the secondary ion increase. Using the participants' data we show that organic SIMS matrix effects can be measured and are remarkably consistent between instruments. We provide recommendations for identifying and compensating for matrix effects. Finally, we demonstrate, using a simple normalization method, that virtually all ToF-SIMS participants could have obtained estimates of volume fraction that were at least as accurate and consistent as XPS.

Keyword(s)

*Laboratories
*Photoelectron Spectroscopy
*Spectrometry, Mass, Secondary Ion
Butylated Hydroxytoluene/analogs & derivatives/chemistry
Fluorenes/chemistry
Fluorobenzenes/chemistry
Organic Chemicals/*chemistry

Notes

Shard, Alexander G
Havelund, Rasmus
Spencer, Steve J
Gilmore, Ian S
Alexander, Morgan R
Angerer, Tina B
Aoyagi, Satoka
Barnes, Jean-Paul
Benayad, Anass
Bernasik, Andrzej
Ceccone, Giacomo
Counsell, Jonathan D P
Deeks, Christopher
Fletcher, John S
Graham, Daniel J
Heuser, Christian
Lee, Tae Geol
Marie, Camille
Marzec, Mateusz M
Mishra, Gautam
Rading, Derk
Renault, Olivier
Scurr, David J
Shon, Hyun Kyong
Spampinato, Valentina
Tian, Hua
Wang, Fuyi
Winograd, Nicholas
Wu, Kui
Wucher, Andreas
Zhou, Yufan
Zhu, Zihua
Cristaudo, Vanina
Poleunis, Claude
EB-002027/EB/NIBIB NIH HHS/
J Phys Chem B. 2015 Aug 20;119(33):10784-97. doi: 10.1021/acs.jpcb.5b05625. Epub 2015 Aug 6.

Reference Type

Journal Article

Secondary Title

J Phys Chem B

Author(s)

Shard, A. G.
Havelund, R.
Spencer, S. J.
Gilmore, I. S.
Alexander, M. R.
Angerer, T. B.
Aoyagi, S.
Barnes, J. P.
Benayad, A.
Bernasik, A.
Ceccone, G.
Counsell, J. D.
Deeks, C.
Fletcher, J. S.
Graham, D. J.
Heuser, C.
Lee, T. G.
Marie, C.
Marzec, M. M.
Mishra, G.
Rading, D.
Renault, O.
Scurr, D. J.
Shon, H. K.
Spampinato, V.
Tian, H.
Wang, F.
Winograd, N.
Wu, K.
Wucher, A.
Zhou, Y.
Zhu, Z.
Cristaudo, V.
Poleunis, C.

Year Published

2015

Date Published

1755648000

Volume Number

119

Issue Number

33

Pages

10784-10797

ISSN/ISBN

1520-5207 (Electronic)
1520-5207 (Linking)

DOI

10.1021/acs.jpcb.5b05625