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Semiconductor Physics, Quantum Electronics & Optoelectronics. 2008. V. 11, N 3. P. 236-239.
Optical and photoelectrical properties of the tetrathiotetracene-
fullerene (TTTC60) film heterostructures
1Institute of Physics, NAS of Ukraine
46, prospect Nauky, 03028 Kiyv, Ukraine
Phone: +38(044) 525-99-57
Abstract. The optical and photoelectrical properties of heterostructures (HS)
SnO 2 ТTTC 60 Ag are investigated. The additional absorption of HS ТTT and C 60 is
revealed in comparison with those for their components, which testifies to the formation
of complexes between the ТTT and C 60 molecules near the ТTT-C 60 interface. Current-
voltage characteristics (J-V) of a dark current is symmetric, as well as corresponds to the
Ohm law for the voltages of 0 to 0.4 V. In the voltage range of 0.4 to 1.0 V, the branch of
J-V at the positive polarity (I + ) goes above that at the negative polarity (I − ) at a SnO 2 -
electrode. Thus, in the double logarithmic scale, I + and I − are described by direct lines
with the angular factors 1.77 and 1.37, accordingly, and exponents in the half-logarithmic
coordinates (log I−U). The open-circuit voltage V oc has a positive polarity at the SnO 2 -
electrode irrespective of the illumination direction of a sample. Photovoltage is caused by
antiblocking bends of bands for holes and electrons near the SnO 2 - and Ag-electrodes of
ТTT and C 60 films, accordingly. The dark effective specific resistance of the HS
SnO 2 ТTTC 60 Ag is equal to 5·10 7 Ohm·cm.
Keywords: fullerene, thin film, optical and photoelectrical properties, absorption spectra.
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