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Semiconductor Physics, Quantum Electronics & Optoelectronics. 2005. V. 8, N 3. P. 092-099.
Photodielectrical properties of the modified С60 films.
Maxwell – Vagner-type polarization
between near-electrode and bulk layers
1Institute for Physics, NAS of Ukraine,
46, prospect Nauky, 03028 Kyiv, Ukraine, e-mail: akoval@iop.kiev.ua
Abstract. Within the frequency interval of 10–1 to 106
Hz investigated were the
frequency dependences of the capacitance C and resistance R for modified С60 films in
darkness and on exposure to the focused white light. A clamping ITO electrode with an
intermediate layer of isotropic liquid (glycerin or distilled water) was taken instead of the
traditionally used deposited top metal electrode. Found are the conditions when C and R
changes are caused by near-electrode (f < 103 Hz) and bulk (f > 104 Hz) processes. It was
shown that the sharp reduction of C and R with growing the frequency corresponds to the
transition from one condition to the other, and such process can be described with
account of the “classical” Maxwell-Wagner mechanism of interlayer polarization. The
relaxation time of such process was found to be equal approximately 10 ns. This time
was shown to depend on the manufacturing technology of С60 films. Having analyzed the
obtained frequency dependences of C and R, an equivalent circuit of the sample was
suggested. We estimated the thicknesses of the liquid layer (≈ 30 µm) and near-electrode
layer of С60 films (tens of nanometers). Comparing the frequency dependences of C and
R on exposure to light of the bottom and top electrodes, it was assumed that the С60 films
under laser UV-irradiation is non-uniform in thickness. tensive amount of development and design variations
by workers hroughout the world.
Keywords: fullerene film, photodielectric properties.
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