TY  - JOUR
AU  - Spassov, Dencho
AU  - Paskaleva, Albena
AU  - Guziewicz, Elżbieta
AU  - Davidović, Vojkan
AU  - Stanković, Srboljub J.
AU  - Đorić-Veljković, Snežana
AU  - Ivanov, Tzvetan
AU  - Stanchev, Todor
AU  - Stojadinović, Ninoslav
PY  - 2021
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/9089
AB  - High-k dielectric stacks are regarded as a promising information storage media in the Charge Trapping Non-Volatile Memories, which are the most viable alternative to the standard floating gate memory technology. The implementation of high-k materials in real devices requires (among the other investigations) estimation of their radiation hardness. Here we report the effect of gamma radiation (60Co source, doses of 10 and 10 kGy) on dielectric properties, memory windows, leakage currents and retention characteristics of nanolaminated HfO2/Al2O3 stacks obtained by atomic layer deposition and its relationship with post-deposition annealing in oxygen and nitrogen ambient. The results reveal that depending on the dose, either increase or reduction of all kinds of electrically active defects (i.e., initial oxide charge, fast and slow interface states) can be observed. Radiation generates oxide charges with a different sign in O2 and N2 annealed stacks. The results clearly demonstrate a substantial increase in memory windows of the as-grown and oxygen treated stacks resulting from enhancement of the electron trapping. The leakage currents and the retention times of O2 annealed stacks are not deteriorated by irradiation, hence these stacks have high radiation tolerance.
T2  - Materials
T1  - Radiation Tolerance and Charge Trapping Enhancement of ALD HfO2/Al2O3 Nanolaminated Dielectrics
VL  - 14
IS  - 4
SP  - 849
DO  - 10.3390/ma14040849
ER  - 

@article{
author = "Spassov, Dencho and Paskaleva, Albena and Guziewicz, Elżbieta and Davidović, Vojkan and Stanković, Srboljub J. and Đorić-Veljković, Snežana and Ivanov, Tzvetan and Stanchev, Todor and Stojadinović, Ninoslav",
year = "2021",
abstract = "High-k dielectric stacks are regarded as a promising information storage media in the Charge Trapping Non-Volatile Memories, which are the most viable alternative to the standard floating gate memory technology. The implementation of high-k materials in real devices requires (among the other investigations) estimation of their radiation hardness. Here we report the effect of gamma radiation (60Co source, doses of 10 and 10 kGy) on dielectric properties, memory windows, leakage currents and retention characteristics of nanolaminated HfO2/Al2O3 stacks obtained by atomic layer deposition and its relationship with post-deposition annealing in oxygen and nitrogen ambient. The results reveal that depending on the dose, either increase or reduction of all kinds of electrically active defects (i.e., initial oxide charge, fast and slow interface states) can be observed. Radiation generates oxide charges with a different sign in O2 and N2 annealed stacks. The results clearly demonstrate a substantial increase in memory windows of the as-grown and oxygen treated stacks resulting from enhancement of the electron trapping. The leakage currents and the retention times of O2 annealed stacks are not deteriorated by irradiation, hence these stacks have high radiation tolerance.",
journal = "Materials",
title = "Radiation Tolerance and Charge Trapping Enhancement of ALD HfO2/Al2O3 Nanolaminated Dielectrics",
volume = "14",
number = "4",
pages = "849",
doi = "10.3390/ma14040849"
}

Spassov, D., Paskaleva, A., Guziewicz, E., Davidović, V., Stanković, S. J., Đorić-Veljković, S., Ivanov, T., Stanchev, T.,& Stojadinović, N.. (2021). Radiation Tolerance and Charge Trapping Enhancement of ALD HfO2/Al2O3 Nanolaminated Dielectrics. in Materials, 14(4), 849.
https://doi.org/10.3390/ma14040849

Spassov D, Paskaleva A, Guziewicz E, Davidović V, Stanković SJ, Đorić-Veljković S, Ivanov T, Stanchev T, Stojadinović N. Radiation Tolerance and Charge Trapping Enhancement of ALD HfO2/Al2O3 Nanolaminated Dielectrics. in Materials. 2021;14(4):849.
doi:10.3390/ma14040849 .

Spassov, Dencho, Paskaleva, Albena, Guziewicz, Elżbieta, Davidović, Vojkan, Stanković, Srboljub J., Đorić-Veljković, Snežana, Ivanov, Tzvetan, Stanchev, Todor, Stojadinović, Ninoslav, "Radiation Tolerance and Charge Trapping Enhancement of ALD HfO2/Al2O3 Nanolaminated Dielectrics" in Materials, 14, no. 4 (2021):849,
https://doi.org/10.3390/ma14040849 . .

TY  - CONF
AU  - Spassov, Dentcho
AU  - Paskaleva, Albena
AU  - Davidović, Vojkan S.
AU  - Đorić-Veljković, Snežana M.
AU  - Stanković, Srboljub J.
AU  - Stojadinović, Ninoslav D.
AU  - Ivanov, Tzvetan E.
AU  - Stanchev, T.
PY  - 2019
UR  - https://ieeexplore.ieee.org/document/8889600/
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/8658
AB  - The effect of γ radiation on the charge trapping and oxide properties of MIS capacitors with nanolaminated RfO2/Ah03 dielectrics are presented. The irradiation with dose of 1 and 10 Mrad generates electron traps thereby substantially enhancing the memory windows of stacks. γ radiation increases the positive oxide charge of the structures, but the effect depends also on the thermal treatment of the stacks. The used doses do not deteriorate the density of interface states, leakage currents and retention characteristics. © 2019 IEEE.
PB  - IEEE
C3  - 2019 IEEE 31st International Conference on Microelectronics (MIEL)
T1  - Impact of γ Radiation on Charge Trapping Properties of Nanolaminated HfO2/Al2O3 ALD Stacks
SP  - 59
EP  - 62
DO  - 10.1109/MIEL.2019.8889600
ER  - 

@conference{
author = "Spassov, Dentcho and Paskaleva, Albena and Davidović, Vojkan S. and Đorić-Veljković, Snežana M. and Stanković, Srboljub J. and Stojadinović, Ninoslav D. and Ivanov, Tzvetan E. and Stanchev, T.",
year = "2019",
abstract = "The effect of γ radiation on the charge trapping and oxide properties of MIS capacitors with nanolaminated RfO2/Ah03 dielectrics are presented. The irradiation with dose of 1 and 10 Mrad generates electron traps thereby substantially enhancing the memory windows of stacks. γ radiation increases the positive oxide charge of the structures, but the effect depends also on the thermal treatment of the stacks. The used doses do not deteriorate the density of interface states, leakage currents and retention characteristics. © 2019 IEEE.",
publisher = "IEEE",
journal = "2019 IEEE 31st International Conference on Microelectronics (MIEL)",
title = "Impact of γ Radiation on Charge Trapping Properties of Nanolaminated HfO2/Al2O3 ALD Stacks",
pages = "59-62",
doi = "10.1109/MIEL.2019.8889600"
}

Spassov, D., Paskaleva, A., Davidović, V. S., Đorić-Veljković, S. M., Stanković, S. J., Stojadinović, N. D., Ivanov, T. E.,& Stanchev, T.. (2019). Impact of γ Radiation on Charge Trapping Properties of Nanolaminated HfO2/Al2O3 ALD Stacks. in 2019 IEEE 31st International Conference on Microelectronics (MIEL)
IEEE., 59-62.
https://doi.org/10.1109/MIEL.2019.8889600

Spassov D, Paskaleva A, Davidović VS, Đorić-Veljković SM, Stanković SJ, Stojadinović ND, Ivanov TE, Stanchev T. Impact of γ Radiation on Charge Trapping Properties of Nanolaminated HfO2/Al2O3 ALD Stacks. in 2019 IEEE 31st International Conference on Microelectronics (MIEL). 2019;:59-62.
doi:10.1109/MIEL.2019.8889600 .

Spassov, Dentcho, Paskaleva, Albena, Davidović, Vojkan S., Đorić-Veljković, Snežana M., Stanković, Srboljub J., Stojadinović, Ninoslav D., Ivanov, Tzvetan E., Stanchev, T., "Impact of γ Radiation on Charge Trapping Properties of Nanolaminated HfO2/Al2O3 ALD Stacks" in 2019 IEEE 31st International Conference on Microelectronics (MIEL) (2019):59-62,
https://doi.org/10.1109/MIEL.2019.8889600 . .

TY  - JOUR
AU  - Stojanović Krasić, Marija
AU  - Mančić, Ana
AU  - Kuzmanović, Slavica
AU  - Đorić-Veljković, Snežana M.
AU  - Stepić, Milutin
PY  - 2017
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/1531
AB  - We numerically analysed various localized modes formed by light beam propagation through one-dimensional composite lattices consisting of two structurally different linear lattices and a linear defect (LD) in one of them. The localized modes are found in the area between the interface and the LD, near the interface and around the LD. It has been confirmed that a LD narrower than the other waveguides (WGs) in the array is better potential barrier and captures the light better than a LD that is wider than the other WGs in the array. Also, it has been shown that a LD narrower than the other WGs in the lattice captures the light more efficiently than any saturable nonlinear defect (ND) of the same width as other elements of the lattice. On the other hand, it is obtained that the influence of a LD wider than the other WGs in the array on light propagation can be mimicked by insertion of an adequate ND whose width coincides with that of the other WGs. Depending on the defect size, its position and input beam parameters, controllable beam trapping, reflection and refraction are observed.
T2  - Optics Communications
T1  - Linear and interface defects in composite linear photonic lattice
VL  - 394
SP  - 6
EP  - 13
DO  - 10.1016/j.optcom.2017.02.021
ER  - 

@article{
author = "Stojanović Krasić, Marija and Mančić, Ana and Kuzmanović, Slavica and Đorić-Veljković, Snežana M. and Stepić, Milutin",
year = "2017",
abstract = "We numerically analysed various localized modes formed by light beam propagation through one-dimensional composite lattices consisting of two structurally different linear lattices and a linear defect (LD) in one of them. The localized modes are found in the area between the interface and the LD, near the interface and around the LD. It has been confirmed that a LD narrower than the other waveguides (WGs) in the array is better potential barrier and captures the light better than a LD that is wider than the other WGs in the array. Also, it has been shown that a LD narrower than the other WGs in the lattice captures the light more efficiently than any saturable nonlinear defect (ND) of the same width as other elements of the lattice. On the other hand, it is obtained that the influence of a LD wider than the other WGs in the array on light propagation can be mimicked by insertion of an adequate ND whose width coincides with that of the other WGs. Depending on the defect size, its position and input beam parameters, controllable beam trapping, reflection and refraction are observed.",
journal = "Optics Communications",
title = "Linear and interface defects in composite linear photonic lattice",
volume = "394",
pages = "6-13",
doi = "10.1016/j.optcom.2017.02.021"
}

Stojanović Krasić, M., Mančić, A., Kuzmanović, S., Đorić-Veljković, S. M.,& Stepić, M.. (2017). Linear and interface defects in composite linear photonic lattice. in Optics Communications, 394, 6-13.
https://doi.org/10.1016/j.optcom.2017.02.021

Stojanović Krasić M, Mančić A, Kuzmanović S, Đorić-Veljković SM, Stepić M. Linear and interface defects in composite linear photonic lattice. in Optics Communications. 2017;394:6-13.
doi:10.1016/j.optcom.2017.02.021 .

Stojanović Krasić, Marija, Mančić, Ana, Kuzmanović, Slavica, Đorić-Veljković, Snežana M., Stepić, Milutin, "Linear and interface defects in composite linear photonic lattice" in Optics Communications, 394 (2017):6-13,
https://doi.org/10.1016/j.optcom.2017.02.021 . .