20.500.12556/RUNG-5885
Molecular alignment on graphene surface determines transport properties of graphene/organic semiconductor transistors
Graphene field-effect transistor structures were used to investigate the role of molecular alignment on charge transport properties of heterostructures comprising a single-layer graphene and variable thickness of N,N′-bis(n-octyl)-(1,7&1,6)-dicyanoperylene-3,4:9,10-bisdicarboximide (PDI8-CN2) - an n-type organic semiconductor. Our atomic force microscopy data show that under selected growth conditions PDI8-CN2 grows in a layer-by-layer fashion up to a second monolayer. The first layer comprises flat-lying molecules, whereas the molecules in the second layer orient themselves in an upright orientation. Transconductance measurements show that the flat-lying molecules have little effect on the position of the Fermi level in graphene. Upright oriented molecules in the second layer instead, have a strong effect as to neutralize native p-type doping of graphene and cause a shift of charge-neutrality level towards the Dirac point. We interpret such behavior in terms of different orientation of the surface dipole on layers with different molecular orientations. At the same time the overall mobility of the charge carriers reaches values exceeding 3000 cm2/Vs.
organski polprevodniki
grafen
transport električnega naboja
true
true
false
Angleški jezik
Ni določen
Delo ni kategorizirano
2020-10-13 00:54:18
2020-10-13 01:14:06
2023-06-09 03:40:43
0000-00-00 00:00:00
2020
0
0
7
105933
87
2020
0000-00-00
Zaloznikova
NiDoloceno
NiDoloceno
0000-00-00
0000-00-00
0000-00-00
32240131
10.1016/j.orgel.2020.105933
URN:SI:UNG:REP:RPMDSL39
Univerza v Novi Gorici
0
1
0