Nanoscale Potential Fluctuations in Nonstoichiometrics Tantalum Oxide
Full article
Общее |
Language:
Английский,
Genre:
Full article,
Status:
Published,
Source type:
Original
|
Journal |
Nanotechnology
ISSN: 0957-4484
, E-ISSN: 1361-6528
|
Output data |
Year: 2018,
Volume: 29,
Number: 42,
Article number
: 425202,
Pages count
: 9
DOI:
10.1088/1361-6528/aad430
|
Tags |
tantalum oxide, nanoscale potential fluctuations, ellipsometry, x-ray photoelectron spectroscopy, Raman scattering, density functional theory, ReRAM |
Authors |
Gritsenko Vladimir A
1,2,3
,
Volodin Vladimir A
1,2
,
Perevalov Timofey V
1,2
,
Kruchinin Vladimir N
1
,
Gerasimova Alina K
1
,
Aliev Vladimir Sh
1
,
Prosvirin Igor P
4
|
Affiliations |
1 |
Rzhanov Institute of Semiconductor Physics SB RAS, 13 Lavrentiev ave., 630090, Novosibirsk, Russia
|
2 |
Novosibirsk State University, 2 Pirogov str., 630090 Novosibirsk, Russia
|
3 |
Novosibirsk State Technical University, 20 K. Marx ave., 630073, Novosibirsk, Russia
|
4 |
Boreskov Institute of Catalysis SB RAS, 5 Lavrentiev ave., 630090, Novosibirsk, Russia
|
|
Funding (1)
1
|
Federal Agency for Scientific Organizations
|
0306-2016-0004
|
The atomic and electronic structure of nonstoichiometric amorphous tantalum oxide (TaO x ) films of different composition has been investigated by means of electron microscopy, x-ray photoelectron spectroscopy, Raman and infrared spectroscopy. The dispersion of the absorption coefficient and refraction index has been studied by spectral ellipsometry. The optical spectra were interpreted using the results of a quantum-chemical simulation for crystalline orthorhombic TaO x . It was found that the presence of oxygen vacancies in the oxygen-deficient TaO x film show an optical absorption peak at 4.6 eV. It has been established that TaOx consists of stoichiometric Ta2O5, metallic Ta clusters less than 20 nm in size, and tantalum suboxides TaO y (y < 2.5). The model of nanoscale potential fluctuations of TaO x bandgap in the range of 0–4.2 eV is proposed and justified. The design of the flash memory element based on the effect of localization of electrons and holes in Ta metallic nanoclusters in the TaOx matrix is proposed.