Electronic Structure of δ-Ta2O5 with Oxygen Vacancy: ab initio Calculations and Comparison with Experiment
Full article
| Общее |
Language:
Английский,
Genre:
Full article,
Status:
Published,
Source type:
Original
|
| Journal |
Journal of Applied Physics
ISSN: 0021-8979
, E-ISSN: 1089-7550
|
| Output data |
Year: 2011,
Volume: 110,
Pages: 024115-1 - 024115-5
Pages count
: 5
DOI:
10.1063/1.3606416
|
| Tags |
ACCESS MEMORY APPLICATIONS; TA2O5 THIN-FILMS; TANTALUM-PENTOXIDE; ION-BOMBARDMENT; SPECTROSCOPY; SURFACES; OXIDE; DIELECTRICS; RETENTION; SILICON |
| Authors |
Ivanov Maxim V.
1
,
Perevalov Timofey V.
1
,
Aliev Vladimir S.
1
,
Gritsenko Vladimir A.
1
,
Kaichev Vasily V.
2
|
| Affiliations |
| 1 |
A. V. Rzhanov Institute of Semiconductor Physics SB RAS, Novosibirsk, 630090, Russia
|
| 2 |
Boreskov Institute of Catalysis SB RAS, Novosibirsk, 630090, Russia
|
|
Funding (1)
Electronic structure of oxygen vacancies in Ta2O5 have been studied theoretically by first-principles calculations and experimentally by x-ray photoelectron spectroscopy. Calculations of δ-Ta2O5 were performed using density functional theory within gradient-corrected approximation with the +U approach. Results indicate that the oxygen vacancy causes a defect level in the energy gap at 1.2 eV above the top of the valence band. To produce oxygen vacancies, amorphous films of Ta2O5 were bombarded with Ar+ ions. XPS results indicate that the Ar-ion bombardment leads to the generation of the oxygen vacancies in Ta2O5 that characterize the peak at 2 eV above the valence band. The calculated spectrum of crystalline δ-Ta2O5 demonstrates qualitative correspondence with the XPS spectrum of the amorphous Ta2O5film after Ar-ion bombardment.