C O M M U N I C A T I O N S
In conclusion, we have prepared a novel pentathiophene-based
swivel cruciform DHPT-SC. The material exhibits a weak, non-
covalent interaction between the arms in solution, and coupled with
the increased solubility of the dimer, this allows for the fluidic
preparation of homogeneous microcrystalline films. OFETs based
2
on DHPT-SC exhibited high field-effect mobility up to 0.012 cm /
V‚s, which is one of the highest values reported to date for wet-
1f
processed OFETs utilizing oligothiophenes. Further modifications
to the structure and an in-depth examination of the morphological
and optical characteristics are underway, which should allow a better
understanding of the structure-property relationship.
Supporting Information Available: Details of experimental
procedures, spectroscopic data, and device fabrication. This material
is available free of charge via the Internet at http://pubs.acs.org.
Figure 3. Characteristics of DHPT-SC OFET device for as-prepared (solid
lines) and annealed sample (dashed-dotted lines). (Left) IDS-V plot at
various gate voltages. (Right) Transfer and square root plot.
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(
right) shows the scattering pattern from a thin film that was
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2
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as typically observed for R,ω-dihexyloligothiophenes. Using the
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(
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The output characteristics from OFETs based on as-prepared
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4
V‚s and a current on/off ratio of 6 × 10 at VDS ) -80 V (Figure
3
, right). The device made from the annealed sample gave a slight
(
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2
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highly desirable OFET property as such transistors have low power
consumption.
5
(
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o
≈ 0V) are very small for both devices, which is a
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