Structure and optical properties of aluminum oxide films (Al2O3) after heating in water vapor and vacuum
https://doi.org/10.61852/2949-3412-2024-2-1-87-105
Abstract
Aluminum oxide films are used as low refractive index layers in multilayer dielectric mirrors, which are expected to be used in ITER plasma diagnostic optical systems. In such mirrors, a film with a low refractive index is the outer layer. In addition to the normal operating modes of ITER, a number of emergency modes are assumed, one of which is the destruction of the water cooling system of the first wall, divertor or blanket. In this case, the vacuum chamber is filled with steam, the parameters of which depend on the location of the destruction and on the stage of operation of the reactor at which the accident occurs. The maximum steam parameters are set by a special system that limits the pressure to 150 kPa, and the maximum temperature of 250°C can be the case when an accident occurs during vacuum training of the chamber.
The work examines the interaction of steam with amorphous films of aluminum oxide deposited on glass of the K-9 grades by reactive magnetron sputtering. It has been shown that exposure of a film 300 nm thick at a temperature of 250°C and a steam pressure of 150 kPa for 2 hours is accompanied by intense hydroxylation of the film and the transformation of the entire oxide film into hydroxides. This leads to severe degradation of light transmission, which may cause a change in the optical properties of the dielectric mirror. As a next step, similar steam exposures are planned of the mirrors in which with a low refractive index layers will alternate with layers of oxides with a high refractive index, such as hafnium, tantalum, and zirconium oxides.
About the Authors
A. E. Gorodetsky
A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences
Russian Federation
Russian Federation
Leninsky pr. 31, 119071 Moscow
A. V. Markin
A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences
Russian Federation
Russian Federation
Leninsky pr. 31, 119071 Moscow
V. L. Bukhovets
A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences
Russian Federation
Russian Federation
Leninsky pr. 31, 119071 Moscow
T. V. Rybkina
A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences
Russian Federation
Russian Federation
Leninsky pr. 31, 119071 Moscow
Yu. M. Nevolin
A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences
Russian Federation
Russian Federation
Leninsky pr. 31, 119071 Moscow
R. Kh. Zalavutdinov
A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences
Russian Federation
Russian Federation
Leninsky pr. 31, 119071 Moscow
References
1. https://ru.wikipedia.org/wiki/Международный_экспериментальный_термоядерный_реактор
2. R. Alba, R. Iglesias and M.A. Cerdeira, Materials to be used in future magnetic confinement fusion reactors: review, Materials, 2022, 15, 6591. doi: 10.3390/ma15196591
3. В.К. Арефьев, М.Я. Беленький, М.А. Блинов, М.А. Готовский, М.Е. Лебедев, Б.С. Фокин, С.А. Григорьев, А.Н. Маханьков, К.С. Сеник и В.Н. Танчук, Диагностика гидравлических характеристик элементов охлаждения дивертора термоядерного реактора ИТЭР методом наружного термографирования, ВАНТ. Сер. Термоядерный синтез, 2011, 4, 3–13.
4. A.V. Gorshkov, S.V. Akhtyrskiy, E.E. Mukhin, I.S. Belbas, A.G. Razdobarin and S.Yu. Tolstyakov, Laser Damage Investigations of Optical Elements for ITER Divertor Thomson Scattering System, Fusion Science and Technology, 2012, 62, no. 1, 104–109. doi: 10.13182/FST12-A14120
5. https://user.iter.org/?uid=N5KF8W
6. https://user.iter.org/?uid=72RWK6
7. https://user.iter.org/?uid=2EBGU5
8. Specifications of the steam and humidity test of the WAVE optical samples. ITER_D_RZC73S v1.6 – 04Feb2016/1.6/Approved.
9. N.B. Abaffy, P. Evans, G. Triani and D.I. McCulloch, Multilayer Alumina and Titania Optical Coatings Prepared by Atomic Layer Deposition, Nanostructured Thin Films, edited by G. B. Smith, A. Lakhtakia, Proc. of SPIE, 2008, 7041, 704109, 1–10. doi: 10.1117/12.794618
10. M. Sterrer, N. Nilins, Sh. Shaikhutdinov, M. Heyde, Th. Schmidt and H.–J. Freund, Interaction of water with oxide thin film model systems (Invited Review), Journ. of Material Research, 2019, 34, no. 3, 360–370. doi: 10.1557/jmr.2018.454
11. T. Mitsunaga, X-ray thin-film measurement techniques. II. Out-of-plane diffraction measurements, The Rigaku Journal, 2009, 25, no. 1, 7–12.
12. M. Milosevic, D. Sting and A. Rein, Diamond composite sensor for ATR spectroscopy, Spectroscopy, 1995, 10, 44–49.
13. J. Grdadolnik, ATR–FTIR Spectroscopy: its advantages and limitations, Acta Chim. Slov., 2002, 49, 631–642.
14. Y. Lan, Y. Zou, X. Ma, L. Xu, L. Shi and J. Zhang, Fabrication of amorphous Al2O3 optical film with various refractive index and low surface roughness, Mater. Res. Express, 2020, 7, 086405. doi: 10.1088/2053-1591/ab0af
15. JCPDS – International Centre for Diffraction Data, 50–0741, 1996.
16. M.K. Gunde, Vibrational modes in amorphous silicon dioxide, Physica B: Condensed Matter, 2000, 292, no. 3–4, 286–295. doi:10.1016/S0921-4526(00)00475-0
17. R.R. Toledo, V.R. Santoyo, D.M. Sánchez and M.M. Rosales, Effect of aluminum precursor on physicochemical properties of Al2O3 by hydrolysis/precipitation method, Nova Scientia, 2018, 10 (1), no. 20, 83–99. doi: 10.21640/ns.v10i20.1217
18. Г.Д. Чукин, Строение оксида алюминия и катализаторов гидрообессеривания. Механизмы реакций, Москва, ООО “Принта”, 2010, 288 с.
19. Y. Ji, X. Yang, Z. Ji, L. Zhu, N. Ma, D. Chen, X. Jia and J. Tang, DFT-calculated IR spectrum amide I, II, III band contributions of N-Methylacetomide fine components, ACS Omega, 2020, 5, no. 15, 8572–8578. doi: 10.1021/acsomega.9b04421
20. M.C. Jollands, M. Blanchard and E. Balan, Structure and theoretical infrared spectra of OH defect in quartz, Eur. J. Mineral., 2020, 32, 311–323. doi: 10.5194/ejm-32-311-2020
21. JCPDS – International Centre for Diffraction Data, 21–1307,1954.
22. Ch. Liu, K. Shih, Yu. Gao, F. Li and L. Wei, Dechlorinating transformation of propachlor through nucleophilic substitution by dithionite on the surface of alumina, J. Soils Sediments, 2012, 12, 724–733. doi: 10.1007/s11368-012-0506-0
Review
For citations:
Gorodetsky A.E., Markin A.V., Bukhovets V.L., Rybkina T.V., Nevolin Yu.M., Zalavutdinov R.Kh. Structure and optical properties of aluminum oxide films (Al2O3) after heating in water vapor and vacuum. Title in english. 2024;(1):87-105. (In Russ.) https://doi.org/10.61852/2949-3412-2024-2-1-87-105
Views:
194
Email this article 