Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Highly oriented VO2 thin films prepared by sol-gel deposition method   Highly oriented VO2 thin films were grown on sapphire substrates by the
sol-gel method that includes a low pressure annealing in an oxygen atmosphere.
This reduction process effectively promotes the formation of the VO2 phase over
a relatively wide range of pressures below 100 mTorr and temperatures above
400oC. X-ray diffraction analysis showed that as-deposited films crystallize
directly to the VO2 phase without passing through intermediate phases. VO2
films have been found to be with [100]- and [010]-preferred orientations on
Al2O3(1012) and Al2O3(1010) substrates, respectively. Both films undergo a
metal-insulator transition with an abrupt change in resistance, with different
transition behaviors observed for the differently oriented films. For the
[010]-oriented VO2 films a larger change in resistance of 1.2x10^4 and a lower
transition temperature are found compared to the values obtained for the
[100]-oriented films.

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The categories of this paper are: hep-th
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The categories of this paper are: nlin
1
The categories of this paper are: cs
3
The categories of this paper are: physics
37
The categories of this paper are: supr-con
16
The categories of this paper are: stat
12
The categories of this paper are: nucl-th
21
The categories of this paper are: adap-org
30
The categories of this paper are: q-alg
32
The categories of this paper are: atom-ph
22
The categories of this paper are: chao-dyn
23
The categories of this paper are: solv-int
27
The categories of this paper are: comp-gas
31
The categories of this paper are: ao-sci
36
The categories of this paper are: cmp-lg
35
The categories of this paper are: mtrl-th