Thermal ALD Synthesis of Vanadium Oxide Thin Films and Its Structural and Electrical Characterization

A method based on the thermal atomic layer deposition for growing vanadium oxides with mixed oxidation states
$(\text{VO}_{\mathrm{x}})$
thin films has been developed. It is shown that, by varying only the growth temperature, it is possible to obtain thin
$\text{VO}_{\mathrm{x}}$
films with a wide range of electrical conductivity and temperature coefficient of resistance. Thin
$\text{vo}_{\mathrm{x}}$
films with TCR in the range from
$-0.53 \%{ }^{\circ} \mathrm{C}$
to
$-4.2 \%{ }^{\circ} \mathrm{C}$
near room temperature were synthesized. Chemical and structural compounds were analyzed by Raman spectroscopy and X-ray photoelectron spectroscopy. In a study of electrical conductivity properties and phase composition of thin films, it was found that an increase in the fraction of the crystal phase of
$\mathrm{V}_{2}\mathrm{O}_{3}$
in the film composition with respect to the fraction of the
$\mathrm{V}_{2}\mathrm{O}_{5}$
leads to an increase in conductivity and TCR. The obtained results path the way for the application of the described synthesis methods of thin films of the vanadium oxide for the IR photodetectors fabrication, such as, microbolometers.