Low-Frequency Dielectric Relaxation in Structures Based on Macroporous Silicon with Meso-Macroporous Skin-Layer.
Materials (Basel)
; 14(10)2021 May 11.
Article
em En
| MEDLINE
| ID: mdl-34064623
ABSTRACT
The spectra of dielectric relaxation of macroporous silicon with a mesoporous skin layer in the frequency range 1-106 Hz during cooling (up to 293-173 K) and heating (293-333 K) are presented. Macroporous silicon (pore diameter ≈ 2.2-2.7 µm) with a meso-macroporous skin layer was obtained by the method of electrochemical anodic dissolution of monocrystalline silicon in a Unno-Imai cell. A mesoporous skin layer with a thickness of about 100-200 nm in the form of cone-shaped nanostructures with pore diameters near 13-25 nm and sizes of skeletal part about 35-40 nm by ion-electron microscopy was observed. The temperature dependence of the relaxation of the most probable relaxation time is characterized by two linear sections with different slope values; the change in the slope character is observed at T ≈ 250 K. The features of the distribution of relaxation times in meso-macroporous silicon at temperatures of 223, 273, and 293 K are revealed. The Havriliak-Negami approach was used for approximation of the relaxation curves εⳠ= f(ν). The existence of a symmetric distribution of relaxers for all temperatures was found (Cole-Cole model). A discussion of results is provided, taking into account the structure of the studied object.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Materials (Basel)
Ano de publicação:
2021
Tipo de documento:
Article
País de afiliação:
Federação Russa