Soft X-ray Reflectivity for DSA BCP Characterization MML · MML Material Measurement Lab Width (nm)...
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Measurement Lab Interface Width (nm) Mass Fraction Homopolymer PMMA PVPH Soft X-ray Reflectivity for DSA BCP Characterization Daniel F. Sunday 1 , Michael Maher 2 , Summer Tein 3 , Gregory Blachut 3 , Yusuke Asano 3 , C. Grant Willson 2 , Chris Ellison 3 , R. Joseph Kline 1 1. Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, MD 2. Department of Chemistry, University of Texas, Austin, TX 3. McKetta Department of Chemical Engineering, University of Texas, Austin, TX Intensity (a.u.) Q (Å -1 ) 280.0 eV 281.5 eV 534.0 eV 534.5 eV 535.0 eV 8 % PVPH PS PMMA PVPH Depth (Å) Mass Fraction Composition Depth (Å) δ Depth (Å) δ Carbon edge Oxygen Edge 280.0 eV 281.5 eV 534.0 eV 534.5 eV 535.0 eV θ θ Reducing BCP Interface Width Through Polymer Blends The addition of a selectively associating additive to a BCP can raise the effective χ between the two phases. Using soft X-ray reflectivity we investigate the distribution of PVPH throughout PS-b-PMMA and how it impacts the interfacial width between blocks. Energy (eV) δ Oxygen Edge PS PMMA PVPH C=O C-O-H C-O-C δ,β profiles can be deconvoluted into composition The addition of PMMA to PS-b-PMMA resulted in no change to the interfacial width, but the addition of PVPH reduced the width by 20 % at a mass fraction of just 0.08. D. F. Sunday, R. J. Kline. Macromolecules 48, 679, 2015 Resonant Soft X-ray Reflectivity Relating Topcoat-Polymer Interface Width to Preferentiality Measuring the Profile of High χ BCPs High χ BCPs generally want to orient parallel to the surface, due to uneven surface energies. Top coats can be used to control the orientation of the BCP. The interface width between the polymer and the topcoat can be related to the neutrality condition which leads to perpendicular orientation. Bates et al. Science 338, 775, 2012 Intensity (a.u.) Q(Å -1 ) Depth (Å) PTMSS fraction Depth (Å) PDSS fraction Depth (Å) PMOST fraction New high χ polymers enable BCPs to reach sub 10-nm pitches. Reflectivity enables the characterization of the interface width and the extent of segregation. Interface Width (nm) Composition (% DTBS) ● PS – TC Bilayer ■ PTMSS – TC Bilayer Intensity (a.u.) Q(Å -1 ) PTMSS - TC Bilayers Intensity (a.u.) Q(Å -1 ) PS - TC Bilayers The interface widths for the neutral composition were equivalent for PS and PTMSS. Sample Pitch (nm) Interface (nm) Interface/ Pitch χN* PS- PTMSS 19.1 5.11 0.26 8.4 PMOST- PTMSS 19.2 3.7 0.195 11 PS-PDSS 19.5 3.2 0.165 12.4 *Durand et al. J Poly Sci Part B. 53, 344, 2015 Higher χN leads to reduced interface width and increased segregation. Near an atomic absorption edge the optical constants change rapidly, enabling control over the contrast between chemically different components in a system. This can be utilized to contrast match specific layers in order to target the interface of interest. θ θ Specular Reflectivity Reflected Intensity Q (Å -1 ) Intensity (a.u.) Critical Edge Bilayer Fringe Total Thickness Fringe BCP Multilayer PS-b-PMMA/PVPH Multilayer Peaks Guiding Pattern Neutral top coat S DTBS PTMSS PS PS-PTMSS (280 eV) PS-PDSS (282 eV) PMOST-PTMSS (535 ev) PS-b-PTMSS PS-b-PDSS PMOST-b-PTMSS Refractive Index (n) n = 1-δ-iβ Depth (Å) δ, β Solid Line -δ Dashed Line -β PS PMMA PVPH Carbon edge Energy (eV) δ PTMSS Preferential Neutral PS Preferential PTMSS Preferential Neutral PS Preferential
Transcript of Soft X-ray Reflectivity for DSA BCP Characterization MML · MML Material Measurement Lab Width (nm)...
MMLMaterial
Measurement Lab
Inte
rfa
ce W
idth
(n
m)
Mass Fraction Homopolymer
PMMA
PVPH
Soft X-ray Reflectivity for DSA BCP CharacterizationDaniel F. Sunday1, Michael Maher2, Summer Tein3, Gregory Blachut3, Yusuke Asano3,
C. Grant Willson2, Chris Ellison3, R. Joseph Kline1
1. Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, MD2. Department of Chemistry, University of Texas, Austin, TX
3. McKetta Department of Chemical Engineering, University of Texas, Austin, TXIn
ten
sity
(a
.u.)
Q (Å-1)
280.0 eV
281.5 eV
534.0 eV
534.5 eV
535.0 eV
8 % PVPH
PSPMMAPVPH
De
pth
(Å
)
Mass Fraction
CompositionD
ep
th (
Å)
δ
De
pth
(Å
)
δ
Carbon edge Oxygen Edge
280.0 eV
281.5 eV
534.0 eV
534.5 eV
535.0 eV
θθ
Reducing BCP Interface Width Through Polymer Blends
The addition of a selectively associating additive to a BCP canraise the effective χ between the two phases. Using soft X-rayreflectivity we investigate the distribution of PVPH throughoutPS-b-PMMA and how it impacts the interfacial width betweenblocks.
Energy (eV)
δ
Oxygen Edge
PSPMMAPVPH
C=O
C-O-H
C-O-C
δ,β profiles can bedeconvoluted intocomposition
The addition of PMMA to PS-b-PMMAresulted in no change to the interfacialwidth, but the addition of PVPH reducedthe width by 20 % at a mass fraction ofjust 0.08.
D. F. Sunday, R. J. Kline. Macromolecules 48, 679, 2015
Resonant Soft X-ray Reflectivity
Relating Topcoat-Polymer Interface Width to Preferentiality
Measuring the Profile of High χ BCPs
High χ BCPs generally want to orient parallel tothe surface, due to uneven surface energies. Topcoats can be used to control the orientation ofthe BCP. The interface width between thepolymer and the topcoat can be related to theneutrality condition which leads toperpendicular orientation.Bates et al. Science 338, 775, 2012
Inte
nsi
ty (
a.u
.)
Q(Å-1)
Depth (Å)PT
MS
S f
ract
ion Depth (Å)
PD
SS
fra
ctio
n
Depth (Å)PM
OS
T f
ract
ion
New high χ polymers enable BCPs to reach sub10-nm pitches. Reflectivity enables thecharacterization of the interface width and theextent of segregation.
Inte
rfa
ce W
idth
(n
m)
Composition (% DTBS)
● PS – TC Bilayer■ PTMSS – TC Bilayer
Inte
nsi
ty (
a.u
.)
Q(Å-1)
PTMSS - TC Bilayers
Inte
nsi
ty (
a.u
.)
Q(Å-1)
PS - TC Bilayers
The interface widths for theneutral composition wereequivalent for PS and PTMSS.
Sample Pitch (nm)
Interface (nm)
Interface/Pitch
χN*
PS-PTMSS
19.1 5.11 0.26 8.4
PMOST-PTMSS
19.2 3.7 0.195 11
PS-PDSS 19.5 3.2 0.165 12.4
*Durand et al. J Poly Sci Part B. 53, 344, 2015
Higher χN leads toreduced interface widthand increased segregation.
Near an atomic absorption edge the optical constants change rapidly, enabling controlover the contrast between chemically different components in a system. This can beutilized to contrast match specific layers in order to target the interface of interest.
θ θ
Specular Reflectivity
Reflected Intensity
Q (Å-1)
Inte
nsi
ty (
a.u
.) Critical Edge
Bilayer Fringe
Total Thickness Fringe
BCP Multilayer
PS-b-PMMA/PVPH
Multilayer Peaks
Guiding Pattern
Neutral top coat
S DTBS
PTMSS
PS
PS-PTMSS (280 eV)
PS-PDSS (282 eV)
PMOST-PTMSS (535 ev)
PS-b-PTMSS
PS-b-PDSS
PMOST-b-PTMSS
Refractive Index (n)n = 1-δ-iβ
Depth (Å)
δ, β
Solid Line -δDashed Line -β
PSPMMAPVPH
Carbon edge
Energy (eV)
δ
PTMSS Preferential
Neutral
PS Preferential
PTMSSPreferential
Neutral
PS Preferential
