Building blocks for n-type molecular and polymeric electronics. Perfluoroalkyl- versus alkyl-functionalized oligothiophenes (nT; n = 2-6). Systematics of thin film microstructure, semiconductor performance, and modeling of majority charge injection in field-effect transistors

Antonio Facchetti, Melissa Mushrush, Myung Han Yoon, Geoffrey R. Hutchison, Mark A Ratner, Tobin J Marks

Research output: Contribution to journalArticle

313 Citations (Scopus)

Abstract

The solid-state properties and FET electrical behavior of several series of α,ω- and β,β′-fluorocarbon- and alkyl-substituted and unsubstituted oligothiophenes nTs (n = 2-6) are compared and contrasted. The thin films were grown by slow vacuum deposition over a range of substrate temperatures and/or by casting from solution and were investigated by X-ray diffraction and scanning electron microscopy. Our results indicate that vacuum deposition at 60-80°C affords films with remarkably similar microstructures despite the extensive H → F substitution. Trends in observed d spacing versus molecular core extension provide quantitative information on molecular orientation. Field-effect transistor measurements performed for all systems and having the same device structure, components, and fabrication conditions demonstrate that all nTs functionalized with fluorocarbon chains at the thiophene termini are n-type semiconductors, in contrast to the p-type activity of the remaining systems. One of these systems, α,ω- diperfluorohexyl-4T, exhibits a mobility of 0.22 cm2/(V s) and an Ion:Ioff ratio of 106, one of the highest so far reported for an n-type organic semiconductor. The effect of substitution regiochemistry on FET majority charge carrier was additionally studied, in the case of a 6T core, by shifting the fluorocarbon substituents from the terminal to the central thiophene units. Finally, we propose a simple theoretical model for electrode/organic interfacial carrier injection. The results suggest why modest substituent-induced changes in the injection barrier can produce working n-type materials.

Original languageEnglish
Pages (from-to)13859-13874
Number of pages16
JournalJournal of the American Chemical Society
Volume126
Issue number42
DOIs
Publication statusPublished - Oct 27 2004

Fingerprint

Fluorocarbons
Charge injection
Semiconductors
Field effect transistors
Vacuum deposition
Thiophenes
Electronic equipment
Thiophene
Semiconductor materials
Vacuum
Thin films
Microstructure
Injections
Substitution reactions
Semiconducting organic compounds
Molecular orientation
Charge carriers
X-Ray Diffraction
Electron Scanning Microscopy
Electrodes

ASJC Scopus subject areas

  • Chemistry(all)

Cite this

@article{7f4c4a0a6ff0456eb48f738866eca65a,
title = "Building blocks for n-type molecular and polymeric electronics. Perfluoroalkyl- versus alkyl-functionalized oligothiophenes (nT; n = 2-6). Systematics of thin film microstructure, semiconductor performance, and modeling of majority charge injection in field-effect transistors",
abstract = "The solid-state properties and FET electrical behavior of several series of α,ω- and β,β′-fluorocarbon- and alkyl-substituted and unsubstituted oligothiophenes nTs (n = 2-6) are compared and contrasted. The thin films were grown by slow vacuum deposition over a range of substrate temperatures and/or by casting from solution and were investigated by X-ray diffraction and scanning electron microscopy. Our results indicate that vacuum deposition at 60-80°C affords films with remarkably similar microstructures despite the extensive H → F substitution. Trends in observed d spacing versus molecular core extension provide quantitative information on molecular orientation. Field-effect transistor measurements performed for all systems and having the same device structure, components, and fabrication conditions demonstrate that all nTs functionalized with fluorocarbon chains at the thiophene termini are n-type semiconductors, in contrast to the p-type activity of the remaining systems. One of these systems, α,ω- diperfluorohexyl-4T, exhibits a mobility of 0.22 cm2/(V s) and an Ion:Ioff ratio of 106, one of the highest so far reported for an n-type organic semiconductor. The effect of substitution regiochemistry on FET majority charge carrier was additionally studied, in the case of a 6T core, by shifting the fluorocarbon substituents from the terminal to the central thiophene units. Finally, we propose a simple theoretical model for electrode/organic interfacial carrier injection. The results suggest why modest substituent-induced changes in the injection barrier can produce working n-type materials.",
author = "Antonio Facchetti and Melissa Mushrush and Yoon, {Myung Han} and Hutchison, {Geoffrey R.} and Ratner, {Mark A} and Marks, {Tobin J}",
year = "2004",
month = "10",
day = "27",
doi = "10.1021/ja0489846",
language = "English",
volume = "126",
pages = "13859--13874",
journal = "Journal of the American Chemical Society",
issn = "0002-7863",
publisher = "American Chemical Society",
number = "42",

}

TY - JOUR

T1 - Building blocks for n-type molecular and polymeric electronics. Perfluoroalkyl- versus alkyl-functionalized oligothiophenes (nT; n = 2-6). Systematics of thin film microstructure, semiconductor performance, and modeling of majority charge injection in field-effect transistors

AU - Facchetti, Antonio

AU - Mushrush, Melissa

AU - Yoon, Myung Han

AU - Hutchison, Geoffrey R.

AU - Ratner, Mark A

AU - Marks, Tobin J

PY - 2004/10/27

Y1 - 2004/10/27

N2 - The solid-state properties and FET electrical behavior of several series of α,ω- and β,β′-fluorocarbon- and alkyl-substituted and unsubstituted oligothiophenes nTs (n = 2-6) are compared and contrasted. The thin films were grown by slow vacuum deposition over a range of substrate temperatures and/or by casting from solution and were investigated by X-ray diffraction and scanning electron microscopy. Our results indicate that vacuum deposition at 60-80°C affords films with remarkably similar microstructures despite the extensive H → F substitution. Trends in observed d spacing versus molecular core extension provide quantitative information on molecular orientation. Field-effect transistor measurements performed for all systems and having the same device structure, components, and fabrication conditions demonstrate that all nTs functionalized with fluorocarbon chains at the thiophene termini are n-type semiconductors, in contrast to the p-type activity of the remaining systems. One of these systems, α,ω- diperfluorohexyl-4T, exhibits a mobility of 0.22 cm2/(V s) and an Ion:Ioff ratio of 106, one of the highest so far reported for an n-type organic semiconductor. The effect of substitution regiochemistry on FET majority charge carrier was additionally studied, in the case of a 6T core, by shifting the fluorocarbon substituents from the terminal to the central thiophene units. Finally, we propose a simple theoretical model for electrode/organic interfacial carrier injection. The results suggest why modest substituent-induced changes in the injection barrier can produce working n-type materials.

AB - The solid-state properties and FET electrical behavior of several series of α,ω- and β,β′-fluorocarbon- and alkyl-substituted and unsubstituted oligothiophenes nTs (n = 2-6) are compared and contrasted. The thin films were grown by slow vacuum deposition over a range of substrate temperatures and/or by casting from solution and were investigated by X-ray diffraction and scanning electron microscopy. Our results indicate that vacuum deposition at 60-80°C affords films with remarkably similar microstructures despite the extensive H → F substitution. Trends in observed d spacing versus molecular core extension provide quantitative information on molecular orientation. Field-effect transistor measurements performed for all systems and having the same device structure, components, and fabrication conditions demonstrate that all nTs functionalized with fluorocarbon chains at the thiophene termini are n-type semiconductors, in contrast to the p-type activity of the remaining systems. One of these systems, α,ω- diperfluorohexyl-4T, exhibits a mobility of 0.22 cm2/(V s) and an Ion:Ioff ratio of 106, one of the highest so far reported for an n-type organic semiconductor. The effect of substitution regiochemistry on FET majority charge carrier was additionally studied, in the case of a 6T core, by shifting the fluorocarbon substituents from the terminal to the central thiophene units. Finally, we propose a simple theoretical model for electrode/organic interfacial carrier injection. The results suggest why modest substituent-induced changes in the injection barrier can produce working n-type materials.

UR - http://www.scopus.com/inward/record.url?scp=6444242950&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=6444242950&partnerID=8YFLogxK

U2 - 10.1021/ja0489846

DO - 10.1021/ja0489846

M3 - Article

C2 - 15493947

AN - SCOPUS:6444242950

VL - 126

SP - 13859

EP - 13874

JO - Journal of the American Chemical Society

JF - Journal of the American Chemical Society

SN - 0002-7863

IS - 42

ER -