Open AccessДиэлектрическая спектроскопия как метод исследования тонких пленок диоксида ванадия
Author(s) -
Александр Валентинович Ильинский,
Р.А. Кастро,
Марина Эрнстовна Пашкевич,
Евгений Борисович Шадрин
Publication year - 2019
Publication title -
žurnal tehničeskoj fiziki
Language(s) - English
Resource type - Journals
eISSN - 1726-748X
pISSN - 0044-4642
DOI - 10.21883/jtf.2019.12.48487.189-19
Subject(s) - dielectric , dissipation factor , materials science , impurity , dielectric loss , doping , germanium , analytical chemistry (journal) , condensed matter physics , chemistry , silicon , physics , optoelectronics , organic chemistry , chromatography
The dielectric spectra of thin (1200 Å) vanadium dioxide films, a material with strong electron-electron correlations, were studied. Both the undoped and germanium-doped VO2: Ge films were studied. For the VO2: Ge, an additional maximum has been detected in the frequency of the dielectric loss spectrum. The fine structure of the spectra was investigated and the physical interpretation of two maxima in the frequency dependence of the tangent of the dielectric loss angle and of two semi-circles on the Cole-Cole diagram was performed. The results were analyzed on the basis of the equivalent electrical circuits of the samples: a single RC-circuit for the case of an undoped VO2 film and a double-circuit for VO2: Ge. The numerical values of the parameters of the model schemes are determined. It has been established that the complicating of equivalent circuit for VO2: Ge compared to undoped VO2 is due to the complication of the electrical response of the doped film to the influence of an electromagnetic field. It is shown that this complication is associated with the acceptor properties of a Ge impurity, which is manifested when the strongly correlated material is doped with an isoelectronic impurity.