Low-temperature carrier dynamics in high-mobility organic transistors of alkylated dinaphtho-thienothiophene as investigated by electron spin resonance

Journal Article · Mon Jul 21 04:00:00 EDT 2014 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4890962· OSTI ID:22311162

Kinoshita, Yutaro; Tanaka, Hisaaki; Kuroda, Shin-ichi ^[1]; Shimoi, Yukihiro ^[2]; Takimiya, Kazuo ^[3]

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1. Department of Applied Physics, Nagoya University, Chikusa, Nagoya 464-8603 (Japan)
2. Nanosystem Research Institute (NRI), National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 (Japan)
3. Emergent Molecular Function Research Group, RIKEN Center for Emergent Matter Science (CEMS), Wako, Saitama 351-0198 (Japan)

Charge carriers in high-mobility organic thin-film transistors of alkylated dinaphtho-thienothiophene (C{sub 10}-DNTT) have been directly observed by field-induced electron spin resonance (FI-ESR) down to 4 K. FI-ESR spectra of π-electron hole carriers of C{sub 10}-DNTT exhibited clear anisotropy, indicating a highly organized end-on molecular orientation at the device interface. The intra-grain and inter-grain carrier motion were probed by the motional narrowing effect of the ESR spectra. The intra-grain motion was clearly observed even at 4 K, showing intrinsically high mobility of C{sub 10}-DNTT crystallites. On the other hand, significantly low activation energy of ∼10 meV for inter-grain carrier hopping, compared with pristine DNTT, was observed, which shows that the alkyl substitution drastically enhances the carrier mobility of DNTT system.

• OSTI ID: 22311162
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 3 Vol. 105; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ACTIVATION ENERGY
ANISOTROPY
CARRIER MOBILITY
CARRIERS
CHARGE CARRIERS
ELECTRON SPIN RESONANCE
EQUIPMENT
INTERFACES
ORGANIC SEMICONDUCTORS
SPECTRA
THIN FILMS
TRANSISTORS