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i kSt. Petersburg State Polytechnical University Journal. Physics and Mathematics. 2024. Vol. 17. No. 3
Научно-технические ведомости СПбГПУ. Физико-математические науки. 17 (3) 2024
Original article
UDC 544.227
DOI: https://doi.org/10.18721/JPM.17308
EFFECT OF ARGON ION BOMBARDMENT ON THE COMPOSITION, ELECTRONIC STRUCTURE AND PHYSICAL PROPERTIES OF CADMIUM FLUORIDE A. A. Abduvayitov 1, D. A. Tashmukhamedova 1, B. E. Umirzakov 1, J. B. Khujaniyozov 1, I. R. Bekpulatov 2 ^, V. V. Loboda 3 1 Tashkent State Technical University Named after Islam Karimov, Tashkent, Uzbekistan;
2 Karshi State University, Tashkent, Uzbekistan;
3 Peter the Great St. Petersburg Polytechnic University, St. Petersburg, Russia
Abstract. In the paper, the effect of bombardment with Ar+ ions on the composition, electronic and crystal structure of the surface layers of bulk single crystal samples and CdF2(111) films has been studied using the methods of Auger electron and ultraviolet photoelectron spectroscopy, high-energy electron diffraction and recording the angular dependences of the reflectance factor of inelastically reflected electrons. The effect of this bombardment on the density of states of valence electrons and energy band parameters of CdF2 was investigated for the first time. The degree of disorder of CdF2 into components and evaporation of fluorine from the surface layers was established to depend on the energy and dose of Ar+ ions. The complete evaporation of F in the form of a diatomic gas was shown for the first time to be observed in the energy range of 1 — 2 keV at a saturation dose.
Keywords: epitaxial layer, heterostructures, ion bombardment, Auger spectrum, photoelectron spectrum, disordered layer, electron density of state
Funding: The studies are being done within the Fundamental Scientific Project No. F-ОТ-2021-422 of The Republic of Uzbekistan and The Ministry of Science and Higher Education of the Russian Federation. The research is funded by the Ministry of Science and Higher Education of the Russian Federation within the framework of the program “The World-Class Research Centre: Advanced Digital Technologies” (Contract No. 075-15-2022-311 dated April 20, 2022).
For citation: Abduvayitov A. A., Tashmukhamedova D. A., Umirzakov B. E., Khujaniyozov J. B., Bekpulatov I. R., Loboda V. V., Effect of argon ion bombardment on the composition, electronic structure and physical properties of cadmium fluoride, St. Petersburg State Polytechnical University Journal. Physics and Mathematics. 17 (3) (2024) 87—96. DOI: https://doi.org/10.18721/JPM.17308
This is an open access article under the CC BY-NC 4.0 license (https://creativecommons. org/licenses/by-nc/4.0/)
Научная статья
УДК 544.227
DOI: https://doi.org/10.18721/JPM.17308
ВЛИЯНИЕ БОМБАРДИРОВКИ ИОНАМИ АРГОНА НА СОСТАВ, ЭЛЕКТРОННУЮ СТРУКТУРУ И ФИЗИЧЕСКИЕ СВОЙСТВА ФТОРИДА КАДМИЯ
А. А. Абдувайитов 1, Д. А. Ташмухамедова 1, Б. Е. Умирзаков 1, Д. Б. Хужаниёзов 1, И. Р. Бекпулатов 2 \ В. В. Лобода 3
1 Ташкентский государственный технический университет им. Ислама Каримова,
© Abduvayitov A. A., Tashmukhamedova D. A., Umirzakov B. E., Khujaniyozov J. B., Bekpulatov I. R., Loboda V. V., 2024. Published by Peter the Great St. Petersburg Polytechnic University.
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г. Ташкент, Узбекистан;
2 Каршинский государственный университет, г. Карши, Узбекистан;
3 Санкт-Петербургский политехнический университет Петра Великого, Санкт-Петербург, Россия
Аннотация. В работе изучено влияние бомбардировки ионами аргона Ar+ на состав, электронную и кристаллическую структуру поверхностных слоев объемных монокристаллических образцов и пленок фторида кадмия CdF2(111). Для этого использованы методы оже-электронной и ультрафиолетовой фотоэлектронной спектроскопии, дифракции быстрых электронов и регистрация угловой зависимости коэффициента отражения неупругоотраженных электронов. Впервые изучено влияние указанной бомбардировки на плотность состояния валентных электронов и энергетические зонные параметры CdF2(111). Установлено, что степень разупорядочения CdF2 на составляющие и испарение фтора с поверхностных слоев зависит от энергии и дозы ионов Ar+. Впервые показано, что полное испарение фтора в виде двухатомного газа наблюдается в области энергий 1 — 2 кэВ при дозе насыщения.
Ключевые слова: эпитаксиальный слой, гетероструктуры, ионная бомбардировка, оже-спектр, фотоэлектронный спектр, неупорядоченный слой, плотность электронных состояний
Финансирование: Работа осуществляется в рамках Фундаментального научного проекта № Ф-ОТ-2021-422 Республики Узбекистан и Министерства науки и образования Российской Федерации. Исследование финансируется Министерством науки и образования Российской Федерации в рамках программы «Исследовательский класс мирового уровня: передовые цифровые технологии» (контракт № 075-15-2022-311 от 20 апреля 2022 года).
Для цитирования: Абдувайитов А. А., Ташмухамедова Д. А., Умирзаков Б. Е., Хужа-ниёзов Д. Б., Бекпулатов И. Р., Лобода В. В. Влияние бомбардировки ионами аргона на состав, электронную структуру и физические свойства фторида кадмия // Научнотехнические ведомости СПбГПУ. Физико-математические науки. 2024. Т. 17. № 3. С. 87-96. DOI: https://doi.org/10.18721/ JPM.17308
Статья открытого доступа, распространяемая по лицензии CC BY-NC 4.0 (https:// creativecommons.org/licenses/by-nc/4.0/)
Introduction
The great interest in epitaxial fluoride layers is associated both with the unique properties of the latter and with the wide potential possibilities of their application in opto- and microelectronics [1 - 13]. In particular, metal fluorides are widely used in the creation of special semiconductor - dielectric - semiconductor (SDS) structures in the three-dimensional integrated circuits. Of particular interest are CdF2/Si(111) heterostructures with a CaF2 buffer layer [9, 14, 15]. The minimum thickness of the CaF2 buffer layer was 0.9 nm [5]. In this case, CaF2 plays the role of a barrier layer for the chemical reaction between CdF2 and Si substrates [9]. At the same time, trivalent germanium turned out to be the most promising for doping CdF2 [16].
Single-crystalline cadmium fluoride is a solid dielectric that can be converted into a semiconductor by doping with donor impurities and subsequent heating in a reducing atmosphere [16 - 18].
In Refs. [19, 20], the energy position of the levels of rare earth (RE) elements in the band diagram of BaF2 and CdF2 crystals was determined. The role of RE3+ and RE2+ ions in the carrier capture, luminescence, and the formation of radiation defects was assessed. It was shown that the significant difference in the luminescent properties of BaF2:RE and CdF2:RE was due to the position of excited energy levels in the band diagram of the crystals. In Ref. [21], Shubnikov -de Haas oscillations and a quantum staircase of the Hall resistance were discovered in a p-CdF2 quantum well limited by CdB^.S barriers on the N-CdF2 surface. Thanks to the low effective
© Абдувайитов А. А., Ташмухамедова Д. А., Умирзаков Б. Е., Хужаниё зов Д. Б., Бекпулатов И. Р., Лобода В. В., 2024. Издатель: Санкт-Петербургский политехнический университет Петра Великого.
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mass of two-dimensional holes, the observation of the quantum Hall effect became possible at room temperature.
Studying the influence of various external influences, especially ion bombardment, on the composition, structure and physical properties of fluorides is of both fundamental and applied interest. In recent years, we have thoroughly studied the effect of ion bombardment on the composition, electronic and crystal structure, emission and optical properties of dielectric films and samples [12 — 27]. However, to date, the effect of low-energy ion bombardment on the composition and properties of CdF2 films has been practically unstudied.
In this work, changes in the composition, electronic and crystal structure of CdF2 (111) upon bombardment with Ar+ ions were studied for the first time.
Experimental methods
The subject of research was a single-crystal sample of CdF2 (111) with a thickness of about 0.5 mm and molecular beam epitaxial (MBE) films of CdF2/Si(111) with a thickness of about 500 A. Before ion bombardment, the samples under study were degassed at T — 1000 K for 3 hours in a vacuum (pressure P — 10-7 Pa). The elemental and chemical compositions of the samples were determined by Auger electron spectroscopy (AES). The degree of amorphization of the CdF2 film upon bombardment with Ar+ ions and its crystallization during annealing, the type and parameters of the lattice were studied by high-energy electron diffraction (HEED) method and by measuring the angular dependences of the reflectance factor n of inelastically reflected electrons. To study the density of state of valence electrons and determine the parameters of energy bands, the method of ultraviolet photoelectron spectroscopy (UPS) was used. All measurements were carried out after the target was cooled to room temperature, in a vacuum with a pressure of at least 10-7 Pa. The choice of the (111) plane has been due to the fact that the CdF2(111) surface has the lowest free energy (£^2 — 540-7 fcm-2, Esi — 1.3540-4 fem-2 and is atomically smooth.
Experimental results and their discussion
The Auger spectrum of a well-cleaned CdF2(111) surface is shown in Fig. 1. It can be seen that the CdF2 surface contains mainly an impurity of oxygen atoms with a concentration of no more than 1 at.%. The CdF2 film surface has high crystalline perfection and an atomically smooth surface with a (1 x 1) structure reflection high-energy electron diffraction (RHEED) image (see inset in Fig. 1).
An analysis of the dependence of the intensity IF of the Auger peak from fluorine at an energy of 646 eV on the irradiation dose to the CdF2(111) surface bombarded by Ar+ ions with different energies E0 (see Fig. 2) allows us to conclude the following. The intensive desorption of fluorine from the surface of CdF2 occurs, starting from the irradiation dose
D = (1 — 5)4013 cm 2 and up to D = 1016
Fig. 1. The Auger spectrum and RHEED images (inset) of the pure CdF2(111) surface
cm-2; the rate of decrease in the intensity IF depending on the energy E0. In particular, for Eo = 0.5 keV at D = 54016 cm-2, the intensity of the Auger peak corresponds to a minimum, but IF is not equal to zero even at D = 1017 cm-2, and thus D = (4 — 5)4016 cm-2 is the saturation dose Ds for E0 = 0.5 keV. For E0 = 1.0 keV, a decrease in IF to zero is observed at D = (6 — 8)4016 cm-2. A decrease in If to zero occurred up to E0 = 2 keV. At E0 more than 2 — 3 keV, the If value, even at dose D more than 1017 cm-2, was above zero. Apparently, at high energies of Ar+ ions, the decomposition of CdF2 predominantly occurs in the surface layer and complete evaporation of fluorine atoms from these layers does not occur. Or, the evaporation of Cd and CdF2 as a whole may begin simultaneously with the evaporation of fluorine atoms.
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E = 646 eV) versus the Ar+ irradiation dose D for CdF2 bombarded by Ar+ ions with different
energy values; E0, keV: 0.5 (1), 1.0 (2), 2.5 (3)
from CdF2 bombarded by Ar+ ions at D = Ds with different energy values; E0, keV: 0.0 (1) 0.5 (2),
angle of incidence of the primary beam) for amorphous CdF2 films on Si(111) substrates; the film thickness values, A: 10 (1), 20 (2), 40 (3), 50 (4). E = 0.8 keV
p
To answer this question, we studied the dependence of IF on the depth h of a CdF2 layer bombarded with Ar+ ions with different energies at D = Ds (Fig. 3). The plots in Fig.3 show that the intensity of the IF peak decreases sharply (by ~ 4 times) at E0 = 0.5 keV, and it practically does not change until the layer depth h = 20 — 80 A, that corresponds to the projected range of Ar+ ions.
Apparently, all F atoms in the form of diatomic gas F2 evaporate from these layers. In the region h ~ 25 - 50 A, the IF concentration increases and, starting from h ~ 50 A, the stoichiometric composition of CdF2 is completely established. However, further studies showed that the CdF2 layers were highly disordered to a depth of h ~ 130 — 150 A. In the case of E0 = 1.0 keV, the surface layers of the cadmium fluoride are completely decomposed into components to a depth of h = 30 — 40 A, and almost all F atoms evaporate from these layers, and hence an amorphous cadmium film with a thickness of d = 30 — 40 A is formed on the surface (see curve 3 in Fig. 3). When CdF2 is bombarded by Ar+ ions with E0 = 5 keV, the greatest decomposition occurs at the depth of the projected range of Ar+ ions (h ~ 60 — 70 A). Apparently, most of the fluorine atoms go into vacuum, and the other part diffuses deep into the target. Therefore, the concentration of F increases significantly at a depth of h = 80 — 100 A.
It is known that the thickness of disordered layers of a single crystal under ion bombardment is very difficult to determine experimentally. In this work, the depth of such layers was assessed by investigation of the angular dependences of the reflectance factor n of inelastically scattered electrons at the different primary electron energies Ep.
The dependences of n on the angle of incidence of the primary beam on the surface, for the Si(111) system with amorphous CdF2 films of various thickness values are presented in Fig. 4. They were recorded at Ep = 0.8 keV. It can be seen that the main Si(111) peak is completely smoothed out at a film thickness of about 50 A. A similar method was used to determine the thicknesses of the CdF2 films at which the main Si peak was smoothed out in the range E = 1 — 10 keV. The results are given in Table.
Using the data from Table, the thickness of disordered layers dp in the CdF2(111) was estimated using the condition when bombarded with Ar+ ions with different energies E0 at doses D = Ds (Fig. 5). This plot shows that
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Table
The dependence of the thickness of the amorphous CdF2/Si(111) films on the primary electron energies Ep
E , keV 0.8 1.0 3.0 5.0 10
d, к 50 80 200 350 500
Footnote: d values were found under the condition when the main peak on the curve п(ф) was smoothed out at a given value of energy Ep.
Fig. 5. A plot of the thickness of disordered layers versus the energy of Ar+ ions
dp increases exponentially from about 130 to 450 A as E0 increases from 0.5 to 5 keV.
The photoelectron spectra of a CdF2/Si(111) epitaxial film before and after bombardment by Ar+ ions at E0 = 1 keV with different doses, taken at hv = 21.2 eV (Fig. 6). These spectra provide information about the density of state of the valence band electrons, and the area under the energy distribution curve is proportional to the quantum yield Y of photoelectrons. The top of the valence band Ev of CdF2 is taken as the reference point. In the spectrum of pure CdF2, there are three clearly defined maxima (peaks) at energies = —1.6 eV, —3.8 eV, and —8.1 eV. It can be assumed that peak E1 appears due to hybridization of the 5s level of Cd with the 2p level of F; the main contribution to the appearance of peak E2 is made by 5s levels of Cd, and that to E3 is made by 2p levels of F.
When CdF2 film is bombarded by Ar+ ions, a slight broadening of the curvilinear energy distribution of photoelectrons is observed at the dose D = 1014 cm-2, and a decrease in the intensity is observed at the peak of Ecv = -1.8 and 8.1 eV. Also, the shift of the peak in the initial state of the spectrum (Ecv = 0.6 - 1.0 eV) to the right leads to
Fig. 6. The photoelectron spectra of the CdF2 bombarded by Ar+ ions with energy E0 = 1 keV.
Doses D, cm-2: 0 (7), 1-1014 (2); 5d015(2), 5d016(4)
a decrease in the gap width E of the CdF2 film. At a dose of 5’ 1015 cm-2, a new peak E characteristic of cadmium appears instead of E1 and E2 peaks, and the value of Y decreases by about 2 times in this case [19, 23].
Conclusion
In this work, the effect of bombardment with argon ions on the composition, electronic and crystal structure of the surface layers of single-crystal samples and CdF2(111) films has been studied. The molecular beam epitaxial film of the CdF2/Si(111) with a thickness of 500 A was shown to have high stoichiometric and crystalline perfection with a surface structure of 1 x 1.
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It was established that the intense desorption of fluorine atoms occurred, which continued up to dose D = (5 — 10) • 1016 cm-2. The concentration of fluorine in the surface layers were found to go down to zero in the region E0 = 1 — 3 keV, and not decrease to zero when E0 being greater than 4 keV. The main mechanisms of these changes were clarified.
For the first time, the thickness of layers enriched with cadmium atoms and the thickness of highly disordered CdF2/Si(111) layers were estimated. The change in the density of state of CdF2 valence electrons upon bombardment by Ar+ ions with E0 = 1 keV was also studied for the first time using ultraviolet photoelectron spectroscopy (UPS) at different doses.
The results obtained in this work can undoubtedly be useful in the development of modern generation communications-electronics equipment.
REFERENCES
1. Sugiyama M., Oshima M., MBE growth of fluorides, Microelectron. J. 27 (4—5) (1996) 361—382.
2. Weng J., Gao Sh.-P., Layer-dependent band gaps and dielectric constants of ultrathin fluorite crystals, J. Phys. Chem. Solids. 148 (Jan) (2021) 109738.
3. Illarionov Y. Y., Vexler M. I., Suturin S. M., et al., Electron tunneling in MIS capacitors with the MBE-grown fluoride layers on Si (111) and Ge (111): Role of transverse momentum conservation, Microelectron. Eng. 88 (7) (2011) 1291-1294.
4. Banshchikov A. G., Illarionov Yu. Yu., Vexler M. I., et al., Trends in reverse-current change in tunnel MIS diodes with calcium fluoride on Si (111) upon the formation of an extra oxide layer, Semicond. 53 (6) (2019) 833-837.
5. Izumi A., Kawabata K., Tsutsui K., et al., Growth of CdF2CaF2Si (111) heterostructure with abrupt interfaces by using thin CaF2 buffer layer, Appl. Surf. Sci. 104-105 (2 Sept) (1996) 417-421.
6. Sokolov N. S., Suturin S. M., MBE-growth peculiarities of fluoride (CdF2-CaF2) thin film structures, Thin Solid Films. 367 (1-2) (2000) 112-119.
7. Mir A., Zaoui A., Bensaid D., The displacement effect of a fluorine atom in CaF2 on the band structure, Appl. Surf. Sci. 439 (1 May) (2018) 1180-1185.
8. Li Zh., Baskurt M., Sahin H., et al., Electronic properties of intrinsic vacancies in single-layer CaF2 and its heterostructure with monolayer MoS2, J. Appl. Phys. 130 (5) (2021) 055301.
9. Kalugin A. I., Sobolev V. V., Optical properties of CdF2 in a wide energy range, Tech. Phys. 49
(3) (2004) 338-341. 2
10. Bekpulatov I. R., Imanova G. T., Kamilov T. S., et al., Formation of n-type CoSi monosilicide film which can be used in instrumentation, Int. J. Modern Phys. B. 37 (17) (2023) 22350164.
11. Bekpulatov I. R., Shomukhammedova D. S., Shukurova D. M., Ibragimova B. V., Obtaining higher manganese silicide films with high thermoelectric properties, E3S Web Conf. 365 (30 Jan) (2023) 05015.
12. Kamilov T. S., Rysbaev A. S., Klechkovskaya V. V., et al., The influence of structural defects in silicon on the formation of photosensitive Mn4Si7-Si(Mn)-Mn4Si7 and Mn4Si7-Si(Mn)-M heterostructures, Appl. Sol. Energy. 55 (6) (2019) 380-384.
13. Rysbaev A. S., Khujaniyozov J. B., Bekpulatov I. R., et al., Effect of thermal and laser annealing on the atom distribution profiles in Si (111) implanted with P+ and B+ ions, J. Surf. Invest.: X-ray, Synchrotron Neutron Tech. 11 (2) (2017) 474-479.
14. Shcheulin A. S., Kupchikov A. K., Angervaks A. E., et al., Radio-frequency response of semiconducting CdF2:In crystals with Schottky barriers, Phys. Rev. B. 63 (20) (2001) 205207.
15. Sorokin L. M., Kyutt R. N., Ratnikov V. V., Kalmykov A. E., Structural characterization of a short-period superlattice based on the CdF2/CaF2/ Si (111), Tech. Phys. Lett. 47 (12) (2021) 893-896.
16. Ryskin A. I., Shcheulin A. S., Angervaks A. E., Semiconductor CdF2: Ga and CdF2 in crystals as media for real-time holography, Mater. 5 (5) (2012) 784-817.
17. Kazansky S. A., Ryskin A. I., Clusters of group-III ions in activated fluorite-type crystals, Phys. Solid State. 44 (8) (2002) 1415-1425.
18. Varlamov A. G., Ulanov V. A., Donornaya provodimost' cristalla CdF2:V3+, otozhonnogo v vakuume [Donor conductivity of the vacuum-annealed CdF2:V3+ crystal], Izvestiya Vysshikh Uchebnykh Zavedenii Rossii. Problemy Energetiki [Energy Problems]. (9-10) (2006) 100-104 (in Russian).
92
Physical materials technology
19. Rodny! P. A., Khodyuk I. V., Stryganyuk G. B., Location of the energy levels of the rare-earth ions in BaF2 and CdF2, Phys. Solid State. 50 (9) (2008) 1639-1643.
20. Dorenbos P., Systematic behaviour in trivalent lanthanide charge transfer energies, J. Phys. Cond. Matter. 15 (49) (2003) 8417-8434.
21. Bagraev N. T., Gimbitskaya O. N., Klyachkin L. E., et al., Quantum Hall effect in (cadmium fluoride)-based nanostructures, Semicond. 43 (1) (2009) 75-77.
22. Umirzakov B. E., Pugacheva T. S., Tashatov A. K., Tashmuchamedova D. A., Electronic structure and optical properties of CaF2 films under low energy Ba+ ion-implantation combined with annealing, Nucl. Instr. and Meth. B. 1661 2 3 4 5 6 7 8 9 10-167 (2 May) (2000) 572-576.
23. Umirzakov B. E., Tashmukhamedova D. A., Muradkabilov D. M., Boltaev Kh. Kh., Electron spectroscopy of the nanostructures created in Si, GaAs, and CaF2 surface layers using low-energy ion implantation, Tech. Phys. 58 (6) (2013) 841-844.
24. Umirzakov B. E., Tashatov A. K., Tashmukhamedova D. A., Normuradov M. T., Protsess formirovaniya nanoplyonok na poverkhnosti CaF2 pri ionnoy implantatsii i posleduyushchem otzhige [Nanofilm formation process on the CaF2 surface during ion implantation and subsequent annealing], Poverkhnost'. Rentgenovskie, Sinkhronnye i Nejtronnye Issledovaniya [Surface. X-ray, Synchrotron and Neutron Investigations]. (12) (2004) 90-94 (in Russian).
25. Umirzakov B. E., Tashmukhamedova D. A., Ruzibaeva M. K., et al., Investigation of change of the composition and structure of the CdF2/Si films surface at the low-energy bombardment, Nucl. Instr. and Meth. B. 326 (1 May) (2014) 3222-325.
26. Tashmukhamedova D. A., Yusupjanova M. B., Emission and optical properties of SiO2/Si films, J. Surf. Invest.: X-ray, Synchrotron Neutron Tech. 10 (6) (2016) 1273-1275.
27. Abduvayitov A. A., Boltaev Kh. Kh., Rozikov G. A., Study of the composition of uncontrolled impurities and the profiles of their distribution at the Ni-CdS interface, J. Surf. Invest.: X-ray, Synchrotron Neutron Tech. 16 (5) (2022) 860-863.
СПИСОК ЛИТЕРАТУРЫ
1. Sugiyama M., Oshima M. MBE growth of fluorides // Microelectronics Journal. 1996. Vol. 27. No. 4-5. Pp. 361-382.
2. Weng J., Gao Sh.-P. Layer-dependent band gaps and dielectric constants of ultrathin fluorite crystals // Journal of Physics and Chemistry of Solids. 2021. Vol. 148. January. P. 109738.
3. Illarionov Y. Y., Vexler M. I., Suturin S. M., Fedorov V. V., Sokolov N. S., Tsutsui K., Takahashi K. Electron tunneling in MIS capacitors with the MBE-grown fluoride layers on Si (111) and Ge (111): Role of transverse momentum conservation // Microelectronic Engineering. 2011. Vol. 88. No. 7. Pp. 1291-1294.
4. Банщиков А. Г., Илларионов Ю. Ю., Векслер М. И., Wachter S., Соколов Н. С. Характер изменения обратного тока в туннельных МДП-диодах с фторидом кальция на Si (111) при создании дополнительного оксидного слоя // Физика и техника полупроводников. 2019. Т. 53. № 6. С. 844-849.
5. Izumi A., Kawabata K., Tsutsui K., Sokolov N. S., Novikov S. V., Khilko A. Yu. Growth of CdF2CaF2Si(111) heterostructure with abrupt interfaces by using thin CaF2 buffer layer // Applied Surface Science. 1996. Vol. 104-105. 2 September. Pp. 417-421.
6. Sokolov N. S., Suturin S. M. MBE-growth peculiarities of fluoride (CdF2-CaF2) thin film structures // Thin Solid Films. 2000. Vol. 367. No. 1-2. Pp. 112-119.
7. Mir A., Zaoui A., Bensaid D. The displacement effect of a fluorine atom in CaF2 on the band structure // Applied Surface Science. 2018. Vol. 439. 1 May. Pp. 1180-1185.
8. Li Zh., Baskurt M., Sahin H., Gao S., Kang J. Electronic properties of intrinsic vacancies in
single-layer CaF2 and its heterostructure with monolayer MoS2 // Journal of Applied Physics. 2021. Vol. 130. No. 5. 2P. 055301. 2
9. Калугин А. И., Соболев В. В. Оптические свойства CdF2 в широкой области энергии // Журнал технической физики. 2004. T. 74. № 3. С. 58-61.
10. Bekpulatov I. R., Imanova G. T., Kamilov T. S., Igamov B. D., Turapov I. Kh. Formation of n-type CoSi monosilicide film which can be used in instrumentation // International Journal of Modern Physics B. 2023. Vol. 37. No. 17. P. 22350164.
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11. Bekpulatov I. R., Shomukhammedova D. S., Shukurova D. M., Ibragimova B. V. Obtaining higher manganese silicide films with high thermoelectric properties // E3S Web of Conferences. 2023. Vol. 365. 30 January. Article No. 05015 (7 p).
12. Kamilov T. S., Rysbaev A. S., Klechkovskaya V. V., Orekhov A. S., Igamov B. D., Bekpulatov I. R.
The influence of structural defects in silicon on the formation of photosensitive Mn4Si7-Si(Mn)-Mn4Si7 and Mn4Si7-Si(Mn) -M heterostructures // Applied Solar Energy. 2019. Vol. 55. No. 6. Pp. 380-4 3784. 4 7
13. Рысбаев А. С., Хужаниязов Ж. Б., Бекпулатов И. Р., Рахимов А. М., Пардаев О. Р. Исследование влияния термического и лазерного отжига на профили распределения атомов в Si (111), имплантированного ионами P+ и B+ // Поверхность. Рентгеновские, синхротронные и нейтронные исследования. 2017. № 4. С. 98-103.
14. Shcheulin A. S., Kupchikov A. K., Angervaks A. E., Onopko D. E., Ryskin A. I., Ritus A. I., Pronin A. V., Volkov A. A., Lunkenheimer P., Loidl A. Radio-frequency response of semiconducting CdF2: In crystals with Schottky barriers // Physical Review B. 2001. Vol. 63. No. 20. P. 205207.
15. Сорокин Л. М., Кютт Р. Н., Ратников В. В., Калмыков А. Е. Структурная характеризация короткопериодной сверхрешетки на основе гетероструктуры CdF2/CaF2/Si(111) методами просвечивающей электронной микроскопии и рентгеновской дифрактометрии // Письма в Журнал технической физики. 2021. Т. 47. № 15. С. 3-6.
16. Ryskin A. I., Shcheulin A. S., Angervaks A. E. Semiconductor CdF2: Ga and CdF2 in crystals as media for real-time holography // Materials (Basel). 2012. Vol. 5. No. 5. Pp. 784-817.
17. Казанский С. А., Рыскин А. И. Кластеры ионов III группы в активированных кристаллах типа флюорита // Физика твердого тела. 2002. Т. 44. № 8. С. 1356-1366.
18. Варламов А. Г., Уланов В. А. Донорная проводимость кристалла CdF2:V3+, отожженного в вакууме // Известия высших учебных заведений. Проблемы энергетики. 2006. № 9-10. С. 100-104.
19. Родный П. А., Ходюк И. В., Стрыганюк Г. Б. Энергетическое положение редкоземельных ионов в BaF2 и CdF2 // Физика твердого тела. 2008. Т. 50. № 9. С. 1578-1581.
20. Dorenbos P. Systematic behaviour in trivalent lanthanide charge transfer energies // Journal of Physics: Condensed Matter. 2003. Vol. 15. No. 49. Pp. 8417-8434.
21. Баграев Н. Т., Гимбицкая О. Н., Клячкин Л. Е., Маляренко А. М., Шелых И. А., Рыскин А. И., Щеулин А. С. Квантовый эффект Холла в наноструктурах на основе фторида кадмия // Физика и техника полупроводников. 2009. Т. 43. № 1. С. 844-849.
22. Umirzakov B. E., Pugacheva T. S., Tashatov A. K., Tashmuchamedova D. A. Electronic structure and optical properties of CaF2 films under low energy Ba+ ion-implantation combined with annealing // Nuclear Instruments and Methods in Physics Research B. 2000. Vol. 166-167. 2 May. Pp. 572-576.
23. Умирзаков Б. Е., Ташмухамедова Д. А., Мурадкабилов Д. М., Болтаев Х. Х. Электронная спектроскопия наноструктур, созданных в поверхностных слоях Si, GaAs и CaF2 методом низкоэнергетической ионной имплантации // Журнал технической физики. 2013. Т. 83. № 6. С. 66-70.
24. Умирзаков Б. Е., Ташатов А. К., Ташмухамедова Д. А., Нормурадов М. Т. Процесс формирования нанопленок на поверхности CaF2 при ионной имплантации и последующем отжиге // Поверхность. Рентгеновские, синхротронные и нейтронные исследования. 2004. № 12. С. 90-94.
25. Umirzakov B. E., Tashmukhamedova D. A., Ruzibaeva M. K., Djurabekova F. G., Danaev S. B. Investigation of change of the composition and structure of the CdF2/Si films surface at the low-energy bombardment // Nuclear Instruments and Methods in Physics Research B. 2014. Vol. 326. 1 May. Pp. 322-325.
26. Ташмухамедова Д. А., Юсупжанова М. Б. Эмиссионные и оптические свойства тонких пленок SiO2/Si // Поверхность. Рентгеновские, синхротронные и нейтронные исследования. 2016. № 12.2С. 89-91.
27. Abduvayitov A. A., Boltaev Kh. Kh., Rozikov G. A. Study of the composition of uncontrolled impurities and the profiles of their distribution at the Ni-CdS interface // Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques. 2022. Vol. 16. No. 5. Pp. 860-863.
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I
Physical materials technology
THE AUTHORS
ABDUVAYITOV Akbarjon A.
Tashkent State Technical University Named after Islam Karimov
2 Universitet St., Tashkent, 100095, Uzbekistan
ORCID: 0000-0001-6453-6523
TASHMUKHAMEDOVA Dilnoza A.
Tashkent State Technical University Named after Islam Karimov
2 Universitet St., Tashkent, 100095, Uzbekistan
ORCID: 0000-0001-5813-7518
UMIRZAKOV Boltakhodja E.
Tashkent State Technical University Named after Islam Karimov
2 Universitet St., Tashkent, 100095, Uzbekistan
ORCID: 0000-0002-9815-2111
KHUJANIYOZOV Jumanazar B.
Tashkent State Technical University Named after Islam Karimov
2 Universitet St., Tashkent, 100095, Uzbekistan
ORCID: 0000-0001-6067-8196
BEKPULATOV Ilkhom R.
Karshi State University
17 Kuchabog St., Karshi,180119, Uzbekistan
ORCID: 0000-0001-7955-3932
LOBODA Vera V.
Peter the Great St. Petersburg Polytechnic University
29 Politechnicheskaya St., St. Petersburg, 195251, Russia
ORCID: 0000-0003-3103-7060
СВЕДЕНИЯ ОБ АВТОРАХ
АБДУВАЙИТОВ Акбаржон Абдумаджитович — канДиДат физико-математических наук, доцент кафедры общей физики Ташкентского государственного технического университета, г. Ташкент, Узбекистан.
100095, Узбекистан, г. Ташкент, Университетская ул., 2. [email protected]
ORCID: 0000-0001-6453-6523
ТАШМУХАМЕДОВА Дилноза Артикбаевна — Доктор физико-математических наук, профессор кафеДры общей физики Ташкентского госуДарственного технического университета имени Ислама Каримова, г. Ташкент, Узбекистан.
100095, Узбекистан, г. Ташкент, Университетская ул., 2
ORCID: 0000-0001-5813-7518
95
St. Petersburg State Polytechnical University Journal. Physics and Mathematics. 2024. Vol. 17. No. 3
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УМИРЗАКОВ Балтоходжа Ерматович — Доктор физико-математических наук, профессор кафедры общей физики Ташкентского государственного технического университета имени Ислама Каримова, г. Ташкент, Узбекистан.
100095, Узбекистан, г. Ташкент, Университетская ул., 2 [email protected]
ORCID: 0000-0002-9815-2111
ХУЖАНИЁЗОВ Джуманазар Бобокулович — кандидат физико-математических наук, доцент кафедры общей физики Ташкентского государственного технического университета, г. Ташкент, Узбекистан.
100095, Узбекистан, г. Ташкент, Университетская ул., 2.
ORCID: 0000-0001-6067-8196
БЕКПУЛАТОВ Ильхом Рустамович — доктор физико-математических наук, проректор по научной работе и инновациям Каршинского государственного университета, г. Карши, Узбекистан.
180119, Узбекистан, г. Карши, ул. Кучабог, 17 [email protected]
ORCID: 0000-0001-7955-3932
ЛОБОДА Вера Владимировна — кандидат физико-математических наук, директор Высшей школы электроники и микросистемной техники Санкт-Петербургского политехнического университета Петра Великого, Санкт-Петербург, Россия.
195251, Россия, г. Санкт-Петербург, Политехническая ул., 29 [email protected]
ORCID: 0000-0003-3103-7060
Received 09.12.2023. Approved after reviewing 19.04.2024. Accepted 19.04.2024.
Статья поступила в редакцию 09.12.2023. Одобрена после рецензирования 19.04.2024. Принята 19.04.2024.
© Санкт-Петербургский политехнический университет Петра Великого, 2024
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