title: Measuring Compositions in Organic Depth Profiling: Results from a VAMAS Interlaboratory Study.
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.
authors.affiliation: †National Physical Laboratory, Teddington, Middlesex TW11 0LW, United Kingdom.
authors.forename: Alexander G
authors.initials: AG
authors.lastname: Shard
authors.affiliation: †National Physical Laboratory, Teddington, Middlesex TW11 0LW, United Kingdom.
authors.forename: Rasmus
authors.initials: R
authors.lastname: Havelund
authors.affiliation: †National Physical Laboratory, Teddington, Middlesex TW11 0LW, United Kingdom.
authors.forename: Steve J
authors.initials: SJ
authors.lastname: Spencer
authors.affiliation: †National Physical Laboratory, Teddington, Middlesex TW11 0LW, United Kingdom.
authors.forename: Ian S
authors.initials: IS
authors.lastname: Gilmore
authors.affiliation: ‡Laboratory of Biophysics and Surface Analysis, University of Nottingham, Nottingham NG7 2RD, United Kingdom.
authors.forename: Morgan R
authors.initials: MR
authors.lastname: Alexander
authors.affiliation: §Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg 40530, Sweden.
authors.forename: Tina B
authors.initials: TB
authors.lastname: Angerer
authors.affiliation: ∥Department of Materials and Life Science, Seikei University, Tokyo 180-8633, Japan.
authors.forename: Satoka
authors.initials: S
authors.lastname: Aoyagi
authors.affiliation: ⊥Université Grenoble Alpes, F-38000 Grenoble, France.|#CEA, LETI, MINATEC Campus, F-38054 Grenoble, France.
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Barnes
authors.affiliation: ⊥Université Grenoble Alpes, F-38000 Grenoble, France.|∇CEA-LITEN/DTNM, F-38054 Grenoble, France.
authors.forename: Anass
authors.initials: A
authors.lastname: Benayad
authors.affiliation: ○AGH University of Science and Technology, Al. Mickiewicza 30, 30-059 Kraków, Poland.
authors.forename: Andrzej
authors.initials: A
authors.lastname: Bernasik
authors.affiliation: ◆Institute for Health and Consumer Protection, Via E. Fermi 2749, TP125, 21027 Ispra (VA), Italy.
authors.forename: Giacomo
authors.initials: G
authors.lastname: Ceccone
authors.affiliation: ¶Kratos Analytical Ltd, Wharfside, Trafford Wharf Road, Manchester M17 1GP, United Kingdom.
authors.forename: Jonathan D P
authors.initials: JD
authors.lastname: Counsell
authors.affiliation: □Thermo Fisher Scientific, East Grinstead, West Sussex RH19 1UB, United Kingdom.
authors.forename: Christopher
authors.initials: C
authors.lastname: Deeks
authors.affiliation: §Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg 40530, Sweden.
authors.forename: John S
authors.initials: JS
authors.lastname: Fletcher
authors.affiliation: ⊗Department of Bioengineering, University of Washington, Seattle, Washington 98195, United States.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Graham
authors.affiliation: ■Faculty of Physics, University Duisburg-Essen, Lotharstraße 1, 47048 Duisburg, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Heuser
authors.affiliation: ▽Korea Research Institute of Standards and Science, 267 Gajeong-ro, Yuseong-gu, Daejeon 305-340, Republic of Korea.
authors.forename: Tae Geol
authors.initials: TG
authors.lastname: Lee
authors.affiliation: ⊥Université Grenoble Alpes, F-38000 Grenoble, France.|#CEA, LETI, MINATEC Campus, F-38054 Grenoble, France.
authors.forename: Camille
authors.initials: C
authors.lastname: Marie
authors.affiliation: ○AGH University of Science and Technology, Al. Mickiewicza 30, 30-059 Kraków, Poland.
authors.forename: Mateusz M
authors.initials: MM
authors.lastname: Marzec
authors.affiliation: ●Corporate Research Analytical Laboratory (CRAL), 3M Deutschland GmbH, Carl-Schurz-Straße 1, Neuss 41460, Germany.
authors.forename: Gautam
authors.initials: G
authors.lastname: Mishra
authors.affiliation: ±ION-TOF GmbH, Heisenberg Straße 15, D-48149 Münster, Germany.
authors.forename: Derk
authors.initials: D
authors.lastname: Rading
authors.affiliation: ⊥Université Grenoble Alpes, F-38000 Grenoble, France.|#CEA, LETI, MINATEC Campus, F-38054 Grenoble, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Renault
authors.affiliation: ‡Laboratory of Biophysics and Surface Analysis, University of Nottingham, Nottingham NG7 2RD, United Kingdom.
authors.forename: David J
authors.initials: DJ
authors.lastname: Scurr
authors.affiliation: ▽Korea Research Institute of Standards and Science, 267 Gajeong-ro, Yuseong-gu, Daejeon 305-340, Republic of Korea.
authors.forename: Hyun Kyong
authors.initials: HK
authors.lastname: Shon
authors.affiliation: ▲Istituto di Fisica dei Plasmi, Consiglio Nazionale delle Ricerche, Via R. Cozzi 53, 20125 Milano, Italy.
authors.forename: Valentina
authors.initials: V
authors.lastname: Spampinato
authors.affiliation: ◇Pennsylvania State University, 104 Chemistry Building, University Park, Pennsylvania 16802, United States.
authors.forename: Hua
authors.initials: H
authors.lastname: Tian
authors.affiliation: ★CAS Key Laboratory of Analytical Chemistry for Living Biosystems, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Fuyi
authors.initials: F
authors.lastname: Wang
authors.affiliation: ◇Pennsylvania State University, 104 Chemistry Building, University Park, Pennsylvania 16802, United States.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Winograd
authors.affiliation: ★CAS Key Laboratory of Analytical Chemistry for Living Biosystems, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Kui
authors.initials: K
authors.lastname: Wu
authors.affiliation: ■Faculty of Physics, University Duisburg-Essen, Lotharstraße 1, 47048 Duisburg, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Wucher
authors.affiliation: $EMSL, Pacific Northwest National Laboratory, Richland, Washington 99354, United States.
authors.forename: Yufan
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: $EMSL, Pacific Northwest National Laboratory, Richland, Washington 99354, United States.
authors.forename: Zihua
authors.initials: Z
authors.lastname: Zhu
authors.forename: Vanina
authors.initials: V
authors.lastname: Cristaudo
authors.forename: Claude
authors.initials: C
authors.lastname: Poleunis
mesh_terms: D002084:Butylated Hydroxytoluene / Q000031:analogs & derivatives / Q000737:chemistry; D005449:Fluorenes / Q000737:chemistry; D005464:Fluorobenzenes / Q000737:chemistry; D007753:Laboratories; D009930:Organic Chemicals / Q000737:chemistry*; D056951:Photoelectron Spectroscopy; D018629:Spectrometry, Mass, Secondary Ion
chemical_list: C496789:9-fluorenylmethoxycarbonyl; D005449:Fluorenes; D005464:Fluorobenzenes; D009930:Organic Chemicals; D002084:Butylated Hydroxytoluene; C045762:Irganox 1010