TY - JOUR
T1 - Electrical doping of poly(9,9-dioctylfluorenyl-2,7-diyl) with tetrafluorotetracyanoquinodimethane by solution method
AU - Hwang, Jaehyung
AU - Kahn, Antoine
PY - 2005/5/15
Y1 - 2005/5/15
N2 - We investigate p -type doping of poly(9,9-dioctylfluorenyl-2,7-diyl) (PFO) films with tetrafluorotetracyanoquinodimethane (F4 -TCNQ) introduced via cosolution. Doped and undoped films are compared using ultraviolet photoelectron spectroscopy (UPS) and current-voltage (I-V) measurement. In spite of the difference between the ionization energy of PFO (5.8 eV) and the electron affinity of F4 -TCNQ (5.24 eV), p doping occurs, as seen from the movement of the Fermi level (EF) toward the polymer highest occupied molecular orbital (HOMO). Interface hole barriers are measured for undoped and doped PFO deposited on three substrates with different work functions, indium-tin-oxide (ITO), gold (Au), and poly-3,4-ethylenedioxythiophene·polystyrenesulfonate (PEDOT·PSS). Doping leads to the formation of a depletion region at the PFO/ITO and PFOAu interfaces. The depletion region is believed to be at the origin of the (hole) current enhancement observed on simple metal/PFO/substrate devices.
AB - We investigate p -type doping of poly(9,9-dioctylfluorenyl-2,7-diyl) (PFO) films with tetrafluorotetracyanoquinodimethane (F4 -TCNQ) introduced via cosolution. Doped and undoped films are compared using ultraviolet photoelectron spectroscopy (UPS) and current-voltage (I-V) measurement. In spite of the difference between the ionization energy of PFO (5.8 eV) and the electron affinity of F4 -TCNQ (5.24 eV), p doping occurs, as seen from the movement of the Fermi level (EF) toward the polymer highest occupied molecular orbital (HOMO). Interface hole barriers are measured for undoped and doped PFO deposited on three substrates with different work functions, indium-tin-oxide (ITO), gold (Au), and poly-3,4-ethylenedioxythiophene·polystyrenesulfonate (PEDOT·PSS). Doping leads to the formation of a depletion region at the PFO/ITO and PFOAu interfaces. The depletion region is believed to be at the origin of the (hole) current enhancement observed on simple metal/PFO/substrate devices.
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U2 - 10.1063/1.1895470
DO - 10.1063/1.1895470
M3 - Article
AN - SCOPUS:20944436563
VL - 97
JO - Journal of Applied Physics
JF - Journal of Applied Physics
SN - 0021-8979
IS - 10
M1 - 103705
ER -