Work function of gold surfaces modified using substituted benzenethiols: Reaction time dependence and thermal stability

Abstract

The work function of Au surfaces modified with various substituted benzenethiols has been systematically investigated for application to the design of organic electronic devices. The work function was found to vary in the range of 4.37 to 5.48 eV depending on the substituted benzenethiol used, which included pentafluorobenzenethiol, 4-fluorobenzenethiol, 4-methylbenzenethiol, 4-aminobenzenethiol, and 4-(dimethylamino)benzenethiol. Subsequent thermal annealing of the modified Au films above 373 K changed the work function back to that of an unmodified Au surface. Meanwhile, thermal desorption spectroscopy revealed species desorbing from the modified Au surfaces, indicating cleavage of the C–S bond as well as the S–Au bond.

Influence of ligand exchange on the electrical transport properties of PbS nanocrystals

“…As mentioned in the Section 2, two different types of devices were printed: one with PFTP deposited on the substrate and one without it. PFTP surface treatment is typically adopted to adjust the work function of the S/D electrodes to improve hole injection in the semiconductor channel but it is also known to reduce charge trapping at the insulator/channel interface and to improve the device stability against bias‐stress .…”

High‐Frequency, Conformable Organic Amplifiers

“…We utilized PFBT self-assembled monolayer to modify the gold work function to approximately −5.5 eV. [ 38 ] This reduction of work function created a good interface for hole injection to the highest occupied molecular orbital level of dinaphtho [2,3-b:29,39-f ] thieno [3,2-b]thiophene (DNTT), −5.4 eV. [ 39 ] Substrates were spincoated with negative photoresist (ZPN-1150, ZEON Corporation) and fi ne patterning of source and drain was done by LED maskless digital exposure system (PMT Corporation).…”

Solution-processed organic field-effect transistors based on dinaphthothienothiophene precursor with chemically modified electrodes

“…It is widely known that the field-effect mobility of bottom-gate/bottom-contact OFETs depends sensitively on a charge injection barrier formed at the source electrode/organic semiconductor interface as compared with that of bottom-gate/top-contact OFETs [8 -10]. The chemical modification of Au source-drain electrodes with a thiolated self-assembled monolayer (SAM) of pentafluorobenzenethiol (PFBT) has been found to increase the work function of Au electrodes (~4.8 eV) to 5.2-5.5 eV [11,12]. This leads to the enhancement in the field-effect mobility of bottom-gate/bottom-contact short-channel OFETs with vacuum-deposited alkylated DNTT thin films as a result of the decrease in the hole injection barrier (contact resistance) at the Au electrode/DNTT interface [13].…”