TY  - JOUR
AU  - Spassov, Dencho
AU  - Paskaleva, Albena
AU  - Guziewicz, Elżbieta
AU  - Davidović, Vojkan
AU  - Stanković, Srboljub
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 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., 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 S, 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, 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
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 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., 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 S, 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, 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  - Davidović, Vojkan
AU  - Danković, Danijel
AU  - Golubović, Snežana
AU  - Đorić-Veljković, Snežana
AU  - Manić, Ivica
AU  - Prijić, Zoran
AU  - Prijić, Aneta
AU  - Stojadinović, Ninoslav
AU  - Stanković, Srboljub
PY  - 2018
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/12131
AB  - In this paper we provide an overview of instabilities observed in commercial power VDMOSFETs subjected to irradiation, NBT stress, and to consecutive exposure to them. The results have indicated that irradiation of previously NBT stressed devices leads to additional threshold voltage shift, while NBT stress effects in previously irradiated devices depend on the gate bias applied during irradiation and on the total dose received. This points to the importance of the order of applied stresses, indicating that for proper insight into the prediction of device behaviour not only harsh conditions, but also the order of exposure have to be considered. It has also been shown that changes in the densities of oxide trapped charge and interface traps during spontaneous recovery after each of applied stresses can be significant, thus leading to additional instability, even though the threshold voltage seems to remain stable, pointing to the need for clarifying the responsible mechanisms.
T2  - Facta universitatis - series: Electronics and Energetics
T1  - NBT stress and radiation related degradation and underlying mechanisms in power VDMOSFETs
VL  - 31
IS  - 3
SP  - 367
EP  - 388
DO  - 10.2298/FUEE1803367D
ER  - 

@article{
author = "Davidović, Vojkan and Danković, Danijel and Golubović, Snežana and Đorić-Veljković, Snežana and Manić, Ivica and Prijić, Zoran and Prijić, Aneta and Stojadinović, Ninoslav and Stanković, Srboljub",
year = "2018",
abstract = "In this paper we provide an overview of instabilities observed in commercial power VDMOSFETs subjected to irradiation, NBT stress, and to consecutive exposure to them. The results have indicated that irradiation of previously NBT stressed devices leads to additional threshold voltage shift, while NBT stress effects in previously irradiated devices depend on the gate bias applied during irradiation and on the total dose received. This points to the importance of the order of applied stresses, indicating that for proper insight into the prediction of device behaviour not only harsh conditions, but also the order of exposure have to be considered. It has also been shown that changes in the densities of oxide trapped charge and interface traps during spontaneous recovery after each of applied stresses can be significant, thus leading to additional instability, even though the threshold voltage seems to remain stable, pointing to the need for clarifying the responsible mechanisms.",
journal = "Facta universitatis - series: Electronics and Energetics",
title = "NBT stress and radiation related degradation and underlying mechanisms in power VDMOSFETs",
volume = "31",
number = "3",
pages = "367-388",
doi = "10.2298/FUEE1803367D"
}

Davidović, V., Danković, D., Golubović, S., Đorić-Veljković, S., Manić, I., Prijić, Z., Prijić, A., Stojadinović, N.,& Stanković, S.. (2018). NBT stress and radiation related degradation and underlying mechanisms in power VDMOSFETs. in Facta universitatis - series: Electronics and Energetics, 31(3), 367-388.
https://doi.org/10.2298/FUEE1803367D

Davidović V, Danković D, Golubović S, Đorić-Veljković S, Manić I, Prijić Z, Prijić A, Stojadinović N, Stanković S. NBT stress and radiation related degradation and underlying mechanisms in power VDMOSFETs. in Facta universitatis - series: Electronics and Energetics. 2018;31(3):367-388.
doi:10.2298/FUEE1803367D .

Davidović, Vojkan, Danković, Danijel, Golubović, Snežana, Đorić-Veljković, Snežana, Manić, Ivica, Prijić, Zoran, Prijić, Aneta, Stojadinović, Ninoslav, Stanković, Srboljub, "NBT stress and radiation related degradation and underlying mechanisms in power VDMOSFETs" in Facta universitatis - series: Electronics and Energetics, 31, no. 3 (2018):367-388,
https://doi.org/10.2298/FUEE1803367D . .