project RFFR 13 -03-
00662a mol-a
Composite materials for
semiconductor-polymer flexible devices electronic engineering
The project aims to develop
methods for the synthesis of vanadium dioxide films with low
temperature phase transition metal-semiconductor junction, which is
necessary for the development of flexible electronics devices, new
types of sensors, optoelectronic converters, volatile memory elements
with the possibility of a superdense recording information. Lowering
the temperature of the phase transition is carried out using a doping
with manganese dioxide, vanadium and chromium. The films obtained by
deposition of a sol-gel method from a methanol solution of vanadyl
acetylacetonate and acetylacetonates of alloying metals ( Cr, Mn) on
various substrates (silicon, Kapton , glass ceramics) with subsequent
heat treatment layers. The dependence of the composition, structure,
electrical and optical properties of functional VO2
films on the
preparation conditions to elucidate the mechanism of doping by
thermogravimetric analysis (TGA ) , rentennograficheski ( XRD ), IR
spectroscopy, including using Fourier studied the thermal stability
(thermolysis) vanadyl acetylacetonate. Found that the thermolysis of
vanadyl acetylacetonate consists of sequential destruction of chemical
bonds in the acetylacetonate ligands soproportsionirovaniya emerging
vanadium oxides varying degrees of oxidation with the formation of
vanadium dioxide. Activation decomposition reactions light provides
additional opportunities reaction control materials. By IR spectroscopy
studied the thermal stability of vanadyl acetylacetonate under UV (
mercury lamp ) and laser irradiation (wavelength 355 nm, pulse energy
and time 8ns and 13.3 mJ , respectively). For manganese and chromium
acetylacetonates composition set solid and gaseous products of
pyrolysis. The temperature dependence of the resistance and the
switching effect in the resulting vanadium dioxide films . The
influence of deposition conditions on the parameters of the resistive
films switching and phase transition metal-semiconductor. On the
basis of vanadium dioxide created sandwich structure Au-VO2-SiO2-Si (p-type) on the effects of electrical switching with memory. Determined
that the switching mechanism is described in the model of the
electronic control metal-insulator transition. To calculate the
electronic structure and determine the nature of the phase transition
VO2 quantum chemistry methods mastered Hubbard model taking into
account the correlation of localized d- or f-electrons.
KEYWORDS
inorganic chemistry , the reactivity of inorganic compounds ,
coordination compounds, transition metal oxides film.
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