C O MMU N I C A T I O N S
Education, Science, Sports, and Culture, Japan. We are grateful to
Professor S. Yamanaka (Hiroshima University) for the XRD
measurements.
Supporting Information Available: Details for the synthesis and
the device fabrication of 1-3, XRDs and AFM images of the thin films
of 1-3, crystallographic information files (CIF) for 2. This material is
References
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Figure 3. Drain-source current (IDS) versus drain-source voltage (VDS
characteristic for 2 (Tsub ) 60 °C).
)
Table 1. Field-Effect Mobility and On/Off Ratio for Transistors of
1-3 Prepared at Different Deposition Temperature of the
Substrate (Tsub
)
1 (DPh-BDT)
2 (DPh-BDS)
3 (DPh-BDTe)
mobility/cm2 V-1 s-1
(on/off ratio)
mobility/cm2 V-1 s-1
(on/off ratio)
mobility/cm2 V-1 s-1
(on/off ratio)
Tsub/°C
rt
4.6 × 10-3
1.6 × 10-2
7.3 × 10-3
(2 × 103)
3.7 × 10-3
(103)
(103)
(104)
60
1.8 × 10-2
(2 × 103)
8.1 × 10-2
(2 × 103)
1.7 × 10-1
(105)
100
7.8 × 10-2
4.2 × 10-3
(102)
(103)
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greater than 105. This FET performance is among the best class of
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than that of 1. This moderate performance may be attributed to the
lower aromatic nature of the tellurophene rings, causing less charge
delocalization over the whole molecule.16
In summary, we have found that a series of diphenylbenzo-
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1,4-dibromobenzene, and all three chalcogen compounds perform
as good p-type transistors. In particular, the benzodiselenophene
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Acknowledgment. This work was partially supported by
Industrial Technology Research Grant Program in 2003 from New
Energy and Industrial Technology Development Organization
(NEDO) of Japan and Regional Science Promotion Program
Evolutional Research. We are also grateful for financial support
from a Grant-in-Aid for Scientific Research on Priority Areas of
Molecular Conductors (No. 15073218) from the Ministry of
JA0496930
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J. AM. CHEM. SOC. VOL. 126, NO. 16, 2004 5085