Deutsche Forschungsgemeinschaft

Link to this page

Deutsche Forschungsgemeinschaft

Authors

Publications

Xenon-ion irradiation of Co/Si bilayers: Magnetic and structural properties

Novaković, Mirjana M.; Popović, Maja; Zhang, Kun; Čubrović, Vladimir; Bibić, Nataša M.; Rakočević, Zlatko Lj.

(2018)

TY  - JOUR
AU  - Novaković, Mirjana M.
AU  - Popović, Maja
AU  - Zhang, Kun
AU  - Čubrović, Vladimir
AU  - Bibić, Nataša M.
AU  - Rakočević, Zlatko Lj.
PY  - 2018
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/7685
AB  - Evolution of the structure of cobalt-silicon films during Xe ions irradiation has been studied and the same is correlated with magnetic properties. The polycrystalline cobalt films were deposited by electron beam evaporation method to a thickness of 50 nm on crystalline silicon (c-Si) and silicon with pre-amorphized surface (a-Si). After deposition the layers were irradiated with 400 keV Xe ions to the fluences in the range of 2-30 x 10(15) ions/cm(2). Structural analysis was done by means of transmission electron microscopy, atomic force microscopy (AFM) and X-ray diffraction (XRD), while the magnetic properties were analyzed by using magneto-optical Kerr effect (MOKE) technique. For the both types of substrate the AFM and XRD results show that after Xe ions irradiation the layers become more rough and the grain size of the crystallites increases; the effects being more evidenced for all fluences for the layers deposited on pre-amorphized Si. The MOKE measurements provided the in-plane azimuthal angular dependence of the hysteresis loops and the change of magnetization with the structural parameters. Although the coercive field is influenced by the surface roughness, in the case of c-Si substrate we found it is much more determined by the size of the crystallites. Additionally, independently on the substrate used the magnetic anisotropy in the Co films disappeared as the Xe ion fluence increased, indicating that the changes of magnetization in both systems occur for similar reasons. (C) 2018 Elsevier B.V. All rights reserved.
T2  - Applied Surface Science
T1  - Xenon-ion irradiation of Co/Si bilayers: Magnetic and structural properties
VL  - 447
SP  - 117
EP  - 124
DO  - 10.1016/j.apsusc.2018.03.215
ER  - 
@article{
author = "Novaković, Mirjana M. and Popović, Maja and Zhang, Kun and Čubrović, Vladimir and Bibić, Nataša M. and Rakočević, Zlatko Lj.",
year = "2018",
abstract = "Evolution of the structure of cobalt-silicon films during Xe ions irradiation has been studied and the same is correlated with magnetic properties. The polycrystalline cobalt films were deposited by electron beam evaporation method to a thickness of 50 nm on crystalline silicon (c-Si) and silicon with pre-amorphized surface (a-Si). After deposition the layers were irradiated with 400 keV Xe ions to the fluences in the range of 2-30 x 10(15) ions/cm(2). Structural analysis was done by means of transmission electron microscopy, atomic force microscopy (AFM) and X-ray diffraction (XRD), while the magnetic properties were analyzed by using magneto-optical Kerr effect (MOKE) technique. For the both types of substrate the AFM and XRD results show that after Xe ions irradiation the layers become more rough and the grain size of the crystallites increases; the effects being more evidenced for all fluences for the layers deposited on pre-amorphized Si. The MOKE measurements provided the in-plane azimuthal angular dependence of the hysteresis loops and the change of magnetization with the structural parameters. Although the coercive field is influenced by the surface roughness, in the case of c-Si substrate we found it is much more determined by the size of the crystallites. Additionally, independently on the substrate used the magnetic anisotropy in the Co films disappeared as the Xe ion fluence increased, indicating that the changes of magnetization in both systems occur for similar reasons. (C) 2018 Elsevier B.V. All rights reserved.",
journal = "Applied Surface Science",
title = "Xenon-ion irradiation of Co/Si bilayers: Magnetic and structural properties",
volume = "447",
pages = "117-124",
doi = "10.1016/j.apsusc.2018.03.215"
}
Novaković, M. M., Popović, M., Zhang, K., Čubrović, V., Bibić, N. M.,& Rakočević, Z. Lj.. (2018). Xenon-ion irradiation of Co/Si bilayers: Magnetic and structural properties. in Applied Surface Science, 447, 117-124.
https://doi.org/10.1016/j.apsusc.2018.03.215
Novaković MM, Popović M, Zhang K, Čubrović V, Bibić NM, Rakočević ZL. Xenon-ion irradiation of Co/Si bilayers: Magnetic and structural properties. in Applied Surface Science. 2018;447:117-124.
doi:10.1016/j.apsusc.2018.03.215 .
Novaković, Mirjana M., Popović, Maja, Zhang, Kun, Čubrović, Vladimir, Bibić, Nataša M., Rakočević, Zlatko Lj., "Xenon-ion irradiation of Co/Si bilayers: Magnetic and structural properties" in Applied Surface Science, 447 (2018):117-124,
https://doi.org/10.1016/j.apsusc.2018.03.215 . .
2
2

Silicide phases formation in Co/c-Si and Co/a-Si systems during thermal annealing

Novaković, Mirjana M.; Popović, Maja; Zhang, Kun; Lieb, K. P.; Bibić, Nataša M.

(2014)

TY  - JOUR
AU  - Novaković, Mirjana M.
AU  - Popović, Maja
AU  - Zhang, Kun
AU  - Lieb, K. P.
AU  - Bibić, Nataša M.
PY  - 2014
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/5890
AB  - The effect of the interface in cobalt-silicon bilayers on the silicide phase formation and microstructure has been investigated. Thin cobalt films were deposited by electron beam evaporation to a thickness of 50 nm on crystalline silicon (c-Si) or silicon with pre-amorphized surface (a-Si). After deposition one set of samples was annealed for 2 h at 200, 300, 400, 500, 600 and 700 degrees C. Another set of samples was irradiated with 400 keV Xe+ ions and then annealed at the same temperatures. Phase transitions were investigated with Rutherford backscattering spectroscopy, X-ray diffraction and cross-sectional transmission electron microscopy. No silicide formation was observed up to 400 degrees C, for both non-irradiated and ion-irradiated samples. When increasing the annealing temperature, the non-irradiated and irradiated Co/c-Si samples showed a similar behaviour: at 500 degrees C, CoSi appeared as the dominant silicide, followed by the formation of CoSi2 at 600 and 700 degrees C. In the case of non-irradiated Co/a-Si samples, no silicide formation occurred up to 700 degrees C, while irradiated samples with pre-amorphized substrate (Co/a-Si) showed a phase sequence similar to that in the Co/c-Si system. The observed phase transitions are found to be consistent with predictions of the effective heat of formation model. (C) 2014 Elsevier B. V. All rights reserved.
T2  - Applied Surface Science
T1  - Silicide phases formation in Co/c-Si and Co/a-Si systems during thermal annealing
VL  - 295
SP  - 158
EP  - 163
DO  - 10.1016/j.apsusc.2014.01.020
ER  - 
@article{
author = "Novaković, Mirjana M. and Popović, Maja and Zhang, Kun and Lieb, K. P. and Bibić, Nataša M.",
year = "2014",
abstract = "The effect of the interface in cobalt-silicon bilayers on the silicide phase formation and microstructure has been investigated. Thin cobalt films were deposited by electron beam evaporation to a thickness of 50 nm on crystalline silicon (c-Si) or silicon with pre-amorphized surface (a-Si). After deposition one set of samples was annealed for 2 h at 200, 300, 400, 500, 600 and 700 degrees C. Another set of samples was irradiated with 400 keV Xe+ ions and then annealed at the same temperatures. Phase transitions were investigated with Rutherford backscattering spectroscopy, X-ray diffraction and cross-sectional transmission electron microscopy. No silicide formation was observed up to 400 degrees C, for both non-irradiated and ion-irradiated samples. When increasing the annealing temperature, the non-irradiated and irradiated Co/c-Si samples showed a similar behaviour: at 500 degrees C, CoSi appeared as the dominant silicide, followed by the formation of CoSi2 at 600 and 700 degrees C. In the case of non-irradiated Co/a-Si samples, no silicide formation occurred up to 700 degrees C, while irradiated samples with pre-amorphized substrate (Co/a-Si) showed a phase sequence similar to that in the Co/c-Si system. The observed phase transitions are found to be consistent with predictions of the effective heat of formation model. (C) 2014 Elsevier B. V. All rights reserved.",
journal = "Applied Surface Science",
title = "Silicide phases formation in Co/c-Si and Co/a-Si systems during thermal annealing",
volume = "295",
pages = "158-163",
doi = "10.1016/j.apsusc.2014.01.020"
}
Novaković, M. M., Popović, M., Zhang, K., Lieb, K. P.,& Bibić, N. M.. (2014). Silicide phases formation in Co/c-Si and Co/a-Si systems during thermal annealing. in Applied Surface Science, 295, 158-163.
https://doi.org/10.1016/j.apsusc.2014.01.020
Novaković MM, Popović M, Zhang K, Lieb KP, Bibić NM. Silicide phases formation in Co/c-Si and Co/a-Si systems during thermal annealing. in Applied Surface Science. 2014;295:158-163.
doi:10.1016/j.apsusc.2014.01.020 .
Novaković, Mirjana M., Popović, Maja, Zhang, Kun, Lieb, K. P., Bibić, Nataša M., "Silicide phases formation in Co/c-Si and Co/a-Si systems during thermal annealing" in Applied Surface Science, 295 (2014):158-163,
https://doi.org/10.1016/j.apsusc.2014.01.020 . .
6
4
6