Supplementary Material (ESI) for Lab on a Chip
This journal is © The Royal Society of Chemistry 2009
Supplemental Figures and text
(a)
(b)
iii)
Figure S1. Schematic diagram for the experimental procedure of fabricating
reversibly bonded nanochannels (RBNs) and subsequent capillarity-driven flow.
(a) A PET support of 50 µm thickness was used to peel off the cured PUA layer
from the silicon master. The channel mold and flat layers of PUA were prepared
by drop-casting a small of amount of the PUA prepolymer onto a bare and a
patterned silicon wafer, respectively, followed by post UV exposure. RBNs were
generated by induced electrostatic attraction upon close contact between the
two layers (i). (b) The RBNs were used as a channel guide for flowing the UV
curable prepolymer (NOA 71 or PEG DA) via capillary action (ii). After capillary
filling, the sample was exposed to UV, leaving behind the cured nanostructures
after removal of the mold as shown in (iii).
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Supplementary Material (ESI) for Lab on a Chip
This journal is © The Royal Society of Chemistry 2009
(a)
(b)
Figure S2 . SEM image showing the meniscus with a pre-spreading film of the
NOA71 on the gold supported channel (a) 300 nm width, 1000 nm height and
(b)) 400 nm width, 200 nm height.
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Supplementary Material (ESI) for Lab on a Chip
This journal is © The Royal Society of Chemistry 2009
edge-deformation of
meniscus
Figure S3 . SEM image showing the meniscus of the PMMA melt that was
pulled into the void spaces of a PUA mold (400 nm width, 800 nm height) at 130
°C for 6 hrs. A similar multi-curvature meniscus is seen from the figure.
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Supplementary Material (ESI) for Lab on a Chip
This journal is © The Royal Society of Chemistry 2009
(a)
CA: ~ 43°
PEG-DA
PUA
(b)
(c)
CA: ~ 42°
CA: ~ near zero
NOA 71
NOA 71
Gold
PUA
Figure S4. Contact angle measurement of (a) PEG-DA on PUA substrate (~43°),
and NOA 71 b) on gold substrate (~ 7°) and (c) on PUA substrate (~ 42°).
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Supplementary Material (ESI) for Lab on a Chip
This journal is © The Royal Society of Chemistry 2009
Dimensionless h, h/W
1.0
0.5
Y-L meniscus
W, 800 nm
W, 400 nm
W, 150 nm
W, 50 nm
0.0
-0.5
-1.0
-2.0
-1.5
-1.0
-0.5
0.0
0.5
1.0
1.5
2.0
Dimensionless x, x/W
Figure S5. Plots of the meniscus profiles with different channel widths. Both
axes were normalized with channel width (W). The data were obtained from the
analysis of SEM images by LABVIEW.
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