Dipolar SAMs Reduce Charge Carrier Injection Barriers in n-Channel Organic Field Effect Transistors

Langmuir : the ACS Journal of Surfaces and Colloids
Malte JesperUwe H F Bunz

Abstract

In this work we examine small conjugated molecules bearing a thiol headgroup as self assembled monolayers (SAM). Functional groups in the SAM-active molecule shift the work function of gold to n-channel semiconductor regimes and improve the wettability of the surface. We examine the effect of the presence of methylene linkers on the orientation of the molecule within the SAM. 3,4,5-Trimethoxythiophenol (TMP-SH) and 3,4,5-trimethoxybenzylthiol (TMP-CH2-SH) were first subjected to computational analysis, predicting work function shifts of -430 and -310 meV. Contact angle measurements show an increase in the wetting envelope compared to that of pristine gold. Infrared (IR) measurements show tilt angles of 22 and 63°, with the methylene-linked molecule (TMP-CH2-SH) attaining a flatter orientation. The actual work function shift as measured with photoemission spectroscopy (XPS/UPS) is even larger, -600 and -430 meV, respectively. The contact resistance between gold electrodes and poly[N,N'-bis(2-octyldodecyl)-naphthalene-1,4:5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5'-(2,2'-bithiophene) (Polyera Aktive Ink, N2200) in n-type OFETs is demonstrated to decrease by 3 orders of magnitude due to the use of TMP-SH and TMP-CH2-SH. The effectiv...Continue Reading

References

Sep 15, 1992·Physical Review. B, Condensed Matter·H L Skriver, N M Rosengaard
Apr 28, 2001·Annual Review of Physical Chemistry·D K Schwartz
Jun 20, 1996·Chemical Reviews·Abraham Ulman
Apr 25, 2002·Journal of the American Chemical Society·John OfferPhilip E Dawson
Nov 10, 2006·The Journal of Physical Chemistry. B·Paul C Rusu, Geert Brocks
May 30, 2008·Accounts of Chemical Research·Georg HeimelJean-Luc Bredas
Apr 1, 2009·Journal of the American Chemical Society·Chang Ho SohnJ L Beauchamp
Apr 24, 2010·Advanced Materials·Georg HeimelEgbert Zojer
May 4, 2010·Advanced Materials·Yugeng Wen, Yunqi Liu
May 28, 2011·Accounts of Chemical Research·Hakan UstaTobin J Marks

❮ Previous
Next ❯

Citations

Mar 3, 2017·Macromolecular Rapid Communications·Haw-Lih SuMohammed Al-Hashimi
Aug 14, 2020·Physical Chemistry Chemical Physics : PCCP·James B DerrValentine I Vullev
Jun 21, 2018·The Journal of Physical Chemistry Letters·Frank S BenneckendorfKlaus Müllen
Dec 12, 2019·ACS Applied Materials & Interfaces·Frank S BenneckendorfKlaus Müllen

❮ Previous
Next ❯

Related Concepts

Related Feeds

Antifungals

An antifungal, also known as an antimycotic medication, is a pharmaceutical fungicide or fungistatic used to treat and prevent mycosis such as athlete's foot, ringworm, candidiasis, cryptococcal meningitis, and others. Discover the latest research on antifungals here.

Antifungals (ASM)

An antifungal, also known as an antimycotic medication, is a pharmaceutical fungicide or fungistatic used to treat and prevent mycosis such as athlete's foot, ringworm, candidiasis, cryptococcal meningitis, and others. Discover the latest research on antifungals here.