While a linear growth behavior is one of the fingerprints of textbook atomic layer deposition processes, the growth often deviates from that behavior in the initial regime, i.e., the first few cycles of a process. To properly understand the growth behavior in the initial regime is particularly important for applications that rely on the exact thickness of very thin films. The determination of the thicknesses of the initial regime, however, often requires special equipment and techniques that are not always available. We propose a thickness determination method that is based on X-ray reflectivity (XRR) measurements on double layer structures, i.e., substrate/base layer/top layer. XRR is a standard thin film characterization method. Utilizing the inherent properties of fast Fourier transformation in combination with a multi-Gaussian fitting routine permits the determination of thicknesses down to . We evaluate the boundaries of our model, which are given by the separation and full width at half maximum of the individual Gaussians. Finally, we compare our results with data from x-ray fluorescence spectroscopy, which is a standard method for measuring ultra-thin films.
References
1.
M.
Knez
, K.
Nielsch
, and L.
Niinistö
, “Synthesis and surface engineering of complex nanostructures by atomic layer deposition
,” Adv. Mater.
19
, 3425
–3438
(2007
).2.
H.
Kim
, H.-B.-R.
Lee
, and W.-J.
Maeng
, “Applications of atomic layer deposition to nanofabrication and emerging nanodevices
,” Thin Solid Films
517
, 2563
–2580
(2009
).3.
M.
Ritala
and J.
Niinistö
, “Industrial applications of atomic layer deposition
,” ECS Trans.
25
, 641
(2019
).4.
W.
Niu
, X.
Li
, S. K.
Karuturi
, D. W.
Fam
, H.
Fan
, S.
Shrestha
, L. H.
Wong
, and A. I. Y.
Tok
, “Applications of atomic layer deposition in solar cells
,” Nanotechnology
26
, 064001
(2015
).5.
J.
Delft
, D.
Garcia-Alonso
, and W.
Kessels
, “Atomic layer deposition for photovoltaics: Applications and prospects for solar cell manufacturing
,” Semicond. Sci. Technol.
27
, 074002
(2012
).6.
S. C.
Riha
, B. M.
Klahr
, E. C.
Tyo
, S.
Seifert
, S.
Vajda
, M. J.
Pellin
, T. W.
Hamann
, and A. B. F.
Martinson
, “Atomic layer deposition of a submonolayer catalyst for the enhanced photoelectrochemical performance of water oxidation with hematite
,” ACS Nano
7
, 2396
–2405
(2013
).7.
S.
Schlicht
, S.
Haschke
, V.
Mikhailovskii
, A.
Manshina
, and J.
Bachmann
, “Highly reversible water oxidation at ordered nanoporous iridium electrodes based on an original atomic layer deposition
,” ChemElectroChem
5
, 1259
–1264
(2018
).8.
X.
Meng
, X.-Q.
Yang
, and X.
Sun
, “Emerging applications of atomic layer deposition for lithium-ion battery studies
,” Adv. Mater.
24
, 3589
–3615
(2012
).9.
Y.
Lei
, J.
Lu
, X.
Luo
, T.
Wu
, P.
Du
, X.
Zhang
, Y.
Ren
, J.
Wen
, D. J.
Miller
, J. T.
Miller
, Y.-K.
Sun
, J. W.
Elam
, and K.
Amine
, “Synthesis of porous carbon supported palladium nanoparticle catalysts by atomic layer deposition: Application for rechargeable lithium–O2 battery
,” Nano Lett.
13
, 4182
–4189
(2013
).10.
M. A.
Alam
and M. L.
Green
, “Mathematical description of atomic layer deposition and its application to the nucleation and growth of HfO2 gate dielectric layers
,” J. Appl. Phys.
94
, 3403
–3413
(2003
).11.
J.-W.
Lim
, H.-S.
Park
, and S.-W.
Kang
, “Kinetic modeling of film growth rate in atomic layer deposition
,” J. Electrochem. Soc.
148
, C403
(2001
).12.
J. A.
Venables
, G. D. T.
Spiller
, and M.
Hanbucken
, “Nucleation and growth of thin films
,” Rep. Prog. Phys.
47
, 399
–459
(1984
).13.
R. L.
Puurunen
and W.
Vandervorst
, “Island growth as a growth mode in atomic layer deposition: A phenomenological model
,” J. Appl. Phys.
96
, 7686
–7695
(2004
).14.
J.
Dendooven
, S.
Pulinthanathu Sree
, K.
De Keyser
, D.
Deduytsche
, J. A.
Martens
, K. F.
Ludwig
, and C.
Detavernier
, “In situ x-ray fluorescence measurements during atomic layer deposition: Nucleation and growth of TiO2 on planar substrates and in nanoporous films
,” J. Phys. Chem. C
115
, 6605
–6610
(2011
).15.
D. M.
Hamann
, D.
Bardgett
, D. L. M.
Cordova
, L. A.
Maynard
, E. C.
Hadland
, A. C.
Lygo
, S. R.
Wood
, M.
Esters
, and D. C.
Johnson
, “Sub-monolayer accuracy in determining the number of atoms per unit area in ultrathin films using x-ray fluorescence
,” Chem. Mater.
30
, 6209
–6216
(2018
).16.
P. Y.
Hung
, C.
Gondran
, A.
Ghatak-Roy
, S.
Terada
, B.
Bunday
, H.
Yeung
, and A.
Diebold
, “X-ray reflectometry and x-ray fluorescence monitoring of the atomic layer deposition process for high-k gate dielectrics
,” J. Vac. Sci. Technol., B
23
, 2244
–2248
(2005
).17.
F.
Fabreguette
, Z.
Sechrist
, J.
Elam
, and S.
George
, “Quartz crystal microbalance study of tungsten atomic layer deposition using WF6 and Si2H6
,” Thin Solid Films
488
, 103
–110
(2005
).18.
R. A.
Wind
and S. M.
George
, “Quartz crystal microbalance studies of Al2O3 atomic layer deposition using trimethylaluminum and water at 125 °C
,” J. Phys. Chem. A
114
, 1281
–1289
(2010
).19.
C. W.
Wiegand
, R.
Faust
, A.
Meinhardt
, R. H.
Blick
, R.
Zierold
, and K.
Nielsch
, “Understanding the growth mechanisms of multilayered systems in atomic layer deposition process
,” Chem. Mater.
30
, 1971
–1979
(2018
).20.
V.
Vandalon
and W. M. M. E.
Kessels
, “Initial growth study of atomic-layer deposition of Al2O3 by vibrational sum-frequency generation
,” Langmuir
35
, 10374
–10382
(2019
).21.
E.
Chason
and T. M.
Mayer
, “Thin film and surface characterization by specular x-ray reflectivity
,” Crit. Rev. Solid State Mater. Sci.
22
, 1
–67
(1997
).22.
V.
Holy
, U.
Pietsch
, and T.
Baumbach
, High-Resolution X-Ray Scattering from Thin Films and Multilayers
, Springer Tracts in Modern Physics (Springer Berlin Heidelberg
, 1999
).23.
J.
Daillant
and A.
Gibaud
, X-Ray and Neutron Reflectivity: Principles and Applications, Lecture Notes in Physics
(Springer Berlin Heidelberg
, 2008
).24.
O.
Durand
and N.
Morizet
, “Fourier-inversion and wavelet-transform methods applied to x-ray reflectometry and hrxrd profiles from complex thin-layered heterostructures
,” in Proceedings of the E-MRS 2005 Spring Meeting Symposium P: Current Trends in Optical and X-ray Metrology of Advanced Materials for Nanoscale Devices, 2006
[Appl. Surf. Sci.
253
, 133
–137
(2006
)].25.
K.
Sakurai
, M.
Mizusawa
, and M.
Ishii
, “Significance of frequency analysis in x-ray reflectivity: Towards analysis which does not depend too much on models
,” Trans. Mater. Res. Soc. Jpn.
33
, 523
–528
(2008
).26.
O.
Durand
, “Characterization of multilayered materials for optoelectronic components by high-resolution x-ray diffractometry and reflectometry: Contribution of numerical treatments
,” in Proceedings of Symposium M On Optical and X-Ray Metrology for Advanced Device Materials Characterization, of the E-MRS 2003 Spring Conference, 2004
[Thin Solid Films
450
, 51
–59
(2004
)].27.
D.
Donnelle
and B.
Rust
, “The fast Fourier transform for experimentalists. Part I. Concepts
,” Comput. Sci. Eng.
7
, 80
–88
(2005
).28.
B.
Davor
, “X-ray diffraction line broadening: Modeling and applications to high-Tc superconductors
,” J. Res. Natl. Inst. Standards Technol.
98
, 321
–353
(1993
).29.
W.
Sevenhans
, M.
Gijs
, Y.
Bruynseraede
, H.
Homma
, and I. K.
Schuller
, “Cumulative disorder and x-ray line broadening in multilayers
,” Phys. Rev. B
34
, 5955
–5958
(1986
).30.
R.
Delhez
, T. H.
de Keijser
, and E. J.
Mittemeijer
, “The x-ray diffraction line broadening due to the diffractometer condition as a function of 2θ
,” J. Phys. E
11
, 649
–652
(1978
).31.
S. K.
Sinha
, E. B.
Sirota
, S.
Garoff
, and H. B.
Stanley
, “X-ray and neutron scattering from rough surfaces
,” Phys. Rev. B
38
, 2297
–2311
(1988
).32.
M.
Lammel
, K.
Geishendorf
, M. A.
Choffel
, D. M.
Hamann
, D. C.
Johnson
, K.
Nielsch
, and A.
Thomas
, “FFT-multi-Gaussian-fitting-routine.ipynb [python 3.x]
,” (2020
).33.
X.-G.
Wang
, W.
Weiss
, S. K.
Shaikhutdinov
, M.
Ritter
, M.
Petersen
, F.
Wagner
, R.
Schlögl
, and M.
Scheffler
, “The hematite (-) (0001) surface: Evidence for domains of distinct chemistry
,” Phys. Rev. Lett.
81
, 1038
–1041
(1998
).34.
“
Hematite (alpha-Fe2O3): General characterization, crystal structure, lattice parameters
,” in Landolt-Börnstein-Group III Condensed Matter
, edited by O.
Madelung
, U.
Rössler
, and M.
Schulz
(Springer-Verlag Berlin Heidelberg
, 2000
), Vol. 41D
.35.
W.
Pies
and A.
Weiss
, “b172, ii.1.1 simple oxides
,” in Landolt-Börnstein-Group III Condensed Matter
, edited by K.-H.
Hellwege
(Springer-Verlag Berlin Heidelberg
, 1975
), Vol. 7B1
.© 2020 Author(s).
2020
Author(s)
You do not currently have access to this content.
