Direct analytical method of contact position effects on the energy-level alignments at organic semiconductor/electrode interfaces using photoemission spectroscopy combined with Ar gas cluster ion beam sputtering.
Poly(3, 4-ethylenedioxythiophene) (PEDOT) polymerized with poly(4-styrenesulfonate) (PSS) is one of the most widely used conducting organic electrodes owing to its outstanding optical/electrical properties and high work function. Because its work function depends significantly on the molecular arrangements between PEDOT and PSS molecules on the surface, the contact position of
PSS films on organic semiconductors (OSCs) must also be an essential consideration. However, existing analysis methods based on in situ deposition/analysis are limited in their ability to accurately investigate the electronic structures of the buried interface regions under the solution-processed electrode or OSC layer in organic devices. Therefore, to overcome such limitations, we propose a top-down method based on photoemission spectroscopy analysis combined with Ar gas cluster ion beam (GCIB) sputtering. Through this method, both energy-level alignments and molecular distributions at various OSC/electrode interfaces can be successfully characterized without reference to any deposition process.
Analytical Science Laboratory of Samsung Advanced Institute of Technology Maetan 3-dong, Yeongtong-gu, Suwon-si, Gyeonggi-do 443-803, Korea.
Dong-Jin
DJ
Yun
JaeGwan
J
Chung
Seong
S
Heon Kim
Yongsu
Y
Kim
SungHoon
S
Park
Minsu
M
Seol
Sung
S
Heo