TY  - JOUR
AU  - Milovanović, Dubravka
AU  - Rajčić, Boris
AU  - Ranković, Dragan
AU  - Stankov, Biljana
AU  - Čekada, Miha
AU  - Ciganović, Jovan
AU  - Đurđević-Milošević, Dragica
AU  - Stević, Zoran
AU  - Kuzmanović, Miroslav
AU  - Šibalija, Tatjana
AU  - Petronić, Sanja
PY  - 2024
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/12723
AB  - This paper presents a study and comparison of surface effects induced by picosecond and nanosecond laser modification of a Ti6Al4V alloy surface under different ambient conditions: air and argon- and nitrogen-rich atmospheres. Detailed surface characterization was performed for all experimental conditions. Damage threshold fluences for picosecond and nanosecond laser irradiation in all three ambient conditions were determined. The observed surface features were a resolidified pool of molten material, craters, hydrodynamic effects and parallel periodic surface structures. Laser-induced periodic surface structures are formed by multi-mode-beam nanosecond laser action and picosecond laser action. Crown-like structures at crater rims are specific features for picosecond Nd:YAG laser action in argon-rich ambient conditions. Elemental analysis of the surfaces indicated nitride compound formation only in the nitrogen-rich ambient conditions. The constituents of the formed plasma were also investigated. Exploring the impact of process control parameters on output responses has been undertaken within the context of laser modification under different environmental conditions. Parametric optimization of the nanosecond laser modification was carried out by implementing an advanced method based on Taguchi’s parametric design and multivariate statistical techniques, and optimal settings are proposed for each atmosphere.
T2  - Micromachines
T1  - Microstructure Formations Resulting from Nanosecond and Picosecond Laser Irradiation of a Ti-Based Alloy under Controlled Atmospheric Conditions and Optimization of the Irradiation Process
VL  - 15
IS  - 1
SP  - 5
DO  - 10.3390/mi15010005
ER  - 

@article{
author = "Milovanović, Dubravka and Rajčić, Boris and Ranković, Dragan and Stankov, Biljana and Čekada, Miha and Ciganović, Jovan and Đurđević-Milošević, Dragica and Stević, Zoran and Kuzmanović, Miroslav and Šibalija, Tatjana and Petronić, Sanja",
year = "2024",
abstract = "This paper presents a study and comparison of surface effects induced by picosecond and nanosecond laser modification of a Ti6Al4V alloy surface under different ambient conditions: air and argon- and nitrogen-rich atmospheres. Detailed surface characterization was performed for all experimental conditions. Damage threshold fluences for picosecond and nanosecond laser irradiation in all three ambient conditions were determined. The observed surface features were a resolidified pool of molten material, craters, hydrodynamic effects and parallel periodic surface structures. Laser-induced periodic surface structures are formed by multi-mode-beam nanosecond laser action and picosecond laser action. Crown-like structures at crater rims are specific features for picosecond Nd:YAG laser action in argon-rich ambient conditions. Elemental analysis of the surfaces indicated nitride compound formation only in the nitrogen-rich ambient conditions. The constituents of the formed plasma were also investigated. Exploring the impact of process control parameters on output responses has been undertaken within the context of laser modification under different environmental conditions. Parametric optimization of the nanosecond laser modification was carried out by implementing an advanced method based on Taguchi’s parametric design and multivariate statistical techniques, and optimal settings are proposed for each atmosphere.",
journal = "Micromachines",
title = "Microstructure Formations Resulting from Nanosecond and Picosecond Laser Irradiation of a Ti-Based Alloy under Controlled Atmospheric Conditions and Optimization of the Irradiation Process",
volume = "15",
number = "1",
pages = "5",
doi = "10.3390/mi15010005"
}

Milovanović, D., Rajčić, B., Ranković, D., Stankov, B., Čekada, M., Ciganović, J., Đurđević-Milošević, D., Stević, Z., Kuzmanović, M., Šibalija, T.,& Petronić, S.. (2024). Microstructure Formations Resulting from Nanosecond and Picosecond Laser Irradiation of a Ti-Based Alloy under Controlled Atmospheric Conditions and Optimization of the Irradiation Process. in Micromachines, 15(1), 5.
https://doi.org/10.3390/mi15010005

Milovanović D, Rajčić B, Ranković D, Stankov B, Čekada M, Ciganović J, Đurđević-Milošević D, Stević Z, Kuzmanović M, Šibalija T, Petronić S. Microstructure Formations Resulting from Nanosecond and Picosecond Laser Irradiation of a Ti-Based Alloy under Controlled Atmospheric Conditions and Optimization of the Irradiation Process. in Micromachines. 2024;15(1):5.
doi:10.3390/mi15010005 .

Milovanović, Dubravka, Rajčić, Boris, Ranković, Dragan, Stankov, Biljana, Čekada, Miha, Ciganović, Jovan, Đurđević-Milošević, Dragica, Stević, Zoran, Kuzmanović, Miroslav, Šibalija, Tatjana, Petronić, Sanja, "Microstructure Formations Resulting from Nanosecond and Picosecond Laser Irradiation of a Ti-Based Alloy under Controlled Atmospheric Conditions and Optimization of the Irradiation Process" in Micromachines, 15, no. 1 (2024):5,
https://doi.org/10.3390/mi15010005 . .

TY  - JOUR
AU  - Ho, Hsin-Chia
AU  - Smiljanić, Milutin
AU  - Jovanović, Zoran M.
AU  - Čekada, Miha
AU  - Kovač, Janez
AU  - Koster, Gertjan
AU  - Hlinka, Jiří
AU  - Hodnik, Nejc
AU  - Spreitzer, Matjaž
PY  - 2023
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/11587
AB  - Development of a robust photocathode using lowcost and high-performing materials, e.g., p-Si, to produce clean fuel hydrogen has remained challenging since the semiconductor substrate is easily susceptible to (photo)corrosion under photoelectrochemical (PEC) operational conditions. A protective layer over the substrate to simultaneously provide corrosion resistance and maintain efficient charge transfer across the device is therefore needed. To this end, in the present work, we utilized pulsed laser deposition (PLD) to prepare a high-quality SrTiO3 (STO) layer to passivate the p-Si substrate using a buffer layer of reduced graphene oxide (rGO). Specifically, a very thin (3.9 nm ∼10 unit cells) STO layer epitaxially overgrown on rGO-buffered Si showed the highest onset potential (0.326 V vs RHE) in comparison to the counterparts with thicker and/or nonepitaxial STO. The photovoltage, flat-band potential, and electrochemical impedance spectroscopy measurements revealed that the epitaxial photocathode was more beneficial for charge separation, charge transfer, and targeted redox reaction than the nonepitaxial one. The STO/rGO/Si with a smooth and highly epitaxial STO layer outperforming the directly contacted STO/Si with a textured and polycrystalline STO layer showed the importance of having a well-defined passivation layer. In addition, the numerous pinholes formed in the directly contacted STO/Si led to the rapid degradation of the photocathode during the PEC measurements. The stability tests demonstrated the soundness of the epitaxial STO layer in passivating Si against corrosion. This study provided a facile approach for preparing a robust protection layer over a photoelectrode substrate in realizing an efficient and, at the same time, durable PEC device.
T2  - ACS Applied Materials & Interfaces
T1  - Robust SrTiO3 Passivation of Silicon Photocathode by Reduced Graphene Oxide for Solar Water Splitting
VL  - 15
IS  - 37
SP  - 44482
EP  - 44492
DO  - 10.1021/acsami.3c07747
ER  - 

@article{
author = "Ho, Hsin-Chia and Smiljanić, Milutin and Jovanović, Zoran M. and Čekada, Miha and Kovač, Janez and Koster, Gertjan and Hlinka, Jiří and Hodnik, Nejc and Spreitzer, Matjaž",
year = "2023",
abstract = "Development of a robust photocathode using lowcost and high-performing materials, e.g., p-Si, to produce clean fuel hydrogen has remained challenging since the semiconductor substrate is easily susceptible to (photo)corrosion under photoelectrochemical (PEC) operational conditions. A protective layer over the substrate to simultaneously provide corrosion resistance and maintain efficient charge transfer across the device is therefore needed. To this end, in the present work, we utilized pulsed laser deposition (PLD) to prepare a high-quality SrTiO3 (STO) layer to passivate the p-Si substrate using a buffer layer of reduced graphene oxide (rGO). Specifically, a very thin (3.9 nm ∼10 unit cells) STO layer epitaxially overgrown on rGO-buffered Si showed the highest onset potential (0.326 V vs RHE) in comparison to the counterparts with thicker and/or nonepitaxial STO. The photovoltage, flat-band potential, and electrochemical impedance spectroscopy measurements revealed that the epitaxial photocathode was more beneficial for charge separation, charge transfer, and targeted redox reaction than the nonepitaxial one. The STO/rGO/Si with a smooth and highly epitaxial STO layer outperforming the directly contacted STO/Si with a textured and polycrystalline STO layer showed the importance of having a well-defined passivation layer. In addition, the numerous pinholes formed in the directly contacted STO/Si led to the rapid degradation of the photocathode during the PEC measurements. The stability tests demonstrated the soundness of the epitaxial STO layer in passivating Si against corrosion. This study provided a facile approach for preparing a robust protection layer over a photoelectrode substrate in realizing an efficient and, at the same time, durable PEC device.",
journal = "ACS Applied Materials & Interfaces",
title = "Robust SrTiO3 Passivation of Silicon Photocathode by Reduced Graphene Oxide for Solar Water Splitting",
volume = "15",
number = "37",
pages = "44482-44492",
doi = "10.1021/acsami.3c07747"
}

Ho, H., Smiljanić, M., Jovanović, Z. M., Čekada, M., Kovač, J., Koster, G., Hlinka, J., Hodnik, N.,& Spreitzer, M.. (2023). Robust SrTiO3 Passivation of Silicon Photocathode by Reduced Graphene Oxide for Solar Water Splitting. in ACS Applied Materials & Interfaces, 15(37), 44482-44492.
https://doi.org/10.1021/acsami.3c07747

Ho H, Smiljanić M, Jovanović ZM, Čekada M, Kovač J, Koster G, Hlinka J, Hodnik N, Spreitzer M. Robust SrTiO3 Passivation of Silicon Photocathode by Reduced Graphene Oxide for Solar Water Splitting. in ACS Applied Materials & Interfaces. 2023;15(37):44482-44492.
doi:10.1021/acsami.3c07747 .

Ho, Hsin-Chia, Smiljanić, Milutin, Jovanović, Zoran M., Čekada, Miha, Kovač, Janez, Koster, Gertjan, Hlinka, Jiří, Hodnik, Nejc, Spreitzer, Matjaž, "Robust SrTiO3 Passivation of Silicon Photocathode by Reduced Graphene Oxide for Solar Water Splitting" in ACS Applied Materials & Interfaces, 15, no. 37 (2023):44482-44492,
https://doi.org/10.1021/acsami.3c07747 . .

TY  - JOUR
AU  - Rajčić, Boris
AU  - Šibalija, Tatjana
AU  - Nikolić, Vladimir M.
AU  - Čekada, Miha
AU  - Savović, Jelena
AU  - Petronić, Sanja
AU  - Milovanović, Dubravka
PY  - 2023
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/10659
AB  - In this experimental study, picosecond laser treatment was performed on a nickel-based superalloy Nimonic 263, aiming to investigate the surface effects induced by irradiation in different atmospheric conditions and, concerning changes in surface composition, regarding the possibility for improvement of its functionality. Besides the varying laser parameters, such as a number of pulses and pulse energy, environmental conditions are also varied. All surface modifications were carried out in standard laboratory conditions and a nitrogen- and argon-rich atmosphere. The resulting topography effects depend on the specific laser treatment and could be categorized as increased roughness, crater formation, and formation of the laser-induced periodic surface structures (LIPSS). Changes in the chemical surface composition are distinguished as the potential formation of the protective oxides/nitrides on the sample surface. Numerous characterization techniques analyse the resulting effects on the topography and surface parameters. The multi-response parametric optimization of the picosecond laser process was performed using an advanced statistical method based on Taguchi’s robust parameter design. Finally, the optimal parameter conditions for Nimonic 263 modification are suggested.
T2  - Materials
T1  - Structural and Functional Picosecond Laser Modification of the Nimonic 263 Superalloy in Different Environmental Conditions and Optimization of the Irradiation Process
VL  - 16
IS  - 3
SP  - 1021
DO  - 10.3390/ma16031021
ER  - 

@article{
author = "Rajčić, Boris and Šibalija, Tatjana and Nikolić, Vladimir M. and Čekada, Miha and Savović, Jelena and Petronić, Sanja and Milovanović, Dubravka",
year = "2023",
abstract = "In this experimental study, picosecond laser treatment was performed on a nickel-based superalloy Nimonic 263, aiming to investigate the surface effects induced by irradiation in different atmospheric conditions and, concerning changes in surface composition, regarding the possibility for improvement of its functionality. Besides the varying laser parameters, such as a number of pulses and pulse energy, environmental conditions are also varied. All surface modifications were carried out in standard laboratory conditions and a nitrogen- and argon-rich atmosphere. The resulting topography effects depend on the specific laser treatment and could be categorized as increased roughness, crater formation, and formation of the laser-induced periodic surface structures (LIPSS). Changes in the chemical surface composition are distinguished as the potential formation of the protective oxides/nitrides on the sample surface. Numerous characterization techniques analyse the resulting effects on the topography and surface parameters. The multi-response parametric optimization of the picosecond laser process was performed using an advanced statistical method based on Taguchi’s robust parameter design. Finally, the optimal parameter conditions for Nimonic 263 modification are suggested.",
journal = "Materials",
title = "Structural and Functional Picosecond Laser Modification of the Nimonic 263 Superalloy in Different Environmental Conditions and Optimization of the Irradiation Process",
volume = "16",
number = "3",
pages = "1021",
doi = "10.3390/ma16031021"
}

Rajčić, B., Šibalija, T., Nikolić, V. M., Čekada, M., Savović, J., Petronić, S.,& Milovanović, D.. (2023). Structural and Functional Picosecond Laser Modification of the Nimonic 263 Superalloy in Different Environmental Conditions and Optimization of the Irradiation Process. in Materials, 16(3), 1021.
https://doi.org/10.3390/ma16031021

Rajčić B, Šibalija T, Nikolić VM, Čekada M, Savović J, Petronić S, Milovanović D. Structural and Functional Picosecond Laser Modification of the Nimonic 263 Superalloy in Different Environmental Conditions and Optimization of the Irradiation Process. in Materials. 2023;16(3):1021.
doi:10.3390/ma16031021 .

Rajčić, Boris, Šibalija, Tatjana, Nikolić, Vladimir M., Čekada, Miha, Savović, Jelena, Petronić, Sanja, Milovanović, Dubravka, "Structural and Functional Picosecond Laser Modification of the Nimonic 263 Superalloy in Different Environmental Conditions and Optimization of the Irradiation Process" in Materials, 16, no. 3 (2023):1021,
https://doi.org/10.3390/ma16031021 . .

TY  - JOUR
AU  - Salatić, Branislav
AU  - Petrović, Suzana
AU  - Peruško, Davor
AU  - Čekada, Miha
AU  - Panjan, Peter
AU  - Pantelić, Dejan
AU  - Jelenković, Branislav
PY  - 2016
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/858
AB  - The surface morphology of the ablation craters created in the multilayer 10x(Al/Ti)/Si system by nanosecond laser pulses at single- and dual wavelength has been studied experimentally and numerically. A complex multilayer thin film including ten (Al/Ti) bilayers deposited by ion sputtering on Si(1 0 0) substrate to a total thickness of 260 nm were illuminated at different laser irradiance in the range 0.25-3.5 x 10(9)W cm(-2). Single pulse laser irradiation was done at normal incidence in air, with the single wavelength, either at 532 nm or 1064 nm or with both laser light simultaneously in the ratio of 1: 10 for energy per pulse between second harmonic and 1064 nm. Most of the absorbed laser energy was rapidly transformed into heat, producing intensive modifications of composition and morphology on the sample surface. The results show an increase in surface roughness, formation of specific nanostructures, appearance of hydrodynamic features and ablation of surface material with crater formation. Applying a small fraction (10%) of the second harmonic in dual-wavelength pulses, a modification of the 10x(Al/Ti)/Si system by a single laser pulse was reflected in the formation of wider and/or deeper craters. Numerical calculations show that the main physical mechanism in ablation process is normal evaporation without phase explosion. The calculated and experimental results agree relatively well for the whole irradiance range, what makes the model applicable to complex Al/Ti multilayer systems. (C) 2015 Elsevier B.V. All rights reserved.
PB  - Elsevier
T2  - Applied Surface Science
T1  - Single- and dual-wavelength laser pulses induced modification in 10x(Al/Ti)/Si multilayer system
VL  - 360
SP  - 559
EP  - 565
DO  - 10.1016/j.apsusc.2015.10.203
ER  - 

@article{
author = "Salatić, Branislav and Petrović, Suzana and Peruško, Davor and Čekada, Miha and Panjan, Peter and Pantelić, Dejan and Jelenković, Branislav",
year = "2016",
abstract = "The surface morphology of the ablation craters created in the multilayer 10x(Al/Ti)/Si system by nanosecond laser pulses at single- and dual wavelength has been studied experimentally and numerically. A complex multilayer thin film including ten (Al/Ti) bilayers deposited by ion sputtering on Si(1 0 0) substrate to a total thickness of 260 nm were illuminated at different laser irradiance in the range 0.25-3.5 x 10(9)W cm(-2). Single pulse laser irradiation was done at normal incidence in air, with the single wavelength, either at 532 nm or 1064 nm or with both laser light simultaneously in the ratio of 1: 10 for energy per pulse between second harmonic and 1064 nm. Most of the absorbed laser energy was rapidly transformed into heat, producing intensive modifications of composition and morphology on the sample surface. The results show an increase in surface roughness, formation of specific nanostructures, appearance of hydrodynamic features and ablation of surface material with crater formation. Applying a small fraction (10%) of the second harmonic in dual-wavelength pulses, a modification of the 10x(Al/Ti)/Si system by a single laser pulse was reflected in the formation of wider and/or deeper craters. Numerical calculations show that the main physical mechanism in ablation process is normal evaporation without phase explosion. The calculated and experimental results agree relatively well for the whole irradiance range, what makes the model applicable to complex Al/Ti multilayer systems. (C) 2015 Elsevier B.V. All rights reserved.",
publisher = "Elsevier",
journal = "Applied Surface Science",
title = "Single- and dual-wavelength laser pulses induced modification in 10x(Al/Ti)/Si multilayer system",
volume = "360",
pages = "559-565",
doi = "10.1016/j.apsusc.2015.10.203"
}

Salatić, B., Petrović, S., Peruško, D., Čekada, M., Panjan, P., Pantelić, D.,& Jelenković, B.. (2016). Single- and dual-wavelength laser pulses induced modification in 10x(Al/Ti)/Si multilayer system. in Applied Surface Science
Elsevier., 360, 559-565.
https://doi.org/10.1016/j.apsusc.2015.10.203

Salatić B, Petrović S, Peruško D, Čekada M, Panjan P, Pantelić D, Jelenković B. Single- and dual-wavelength laser pulses induced modification in 10x(Al/Ti)/Si multilayer system. in Applied Surface Science. 2016;360:559-565.
doi:10.1016/j.apsusc.2015.10.203 .

Salatić, Branislav, Petrović, Suzana, Peruško, Davor, Čekada, Miha, Panjan, Peter, Pantelić, Dejan, Jelenković, Branislav, "Single- and dual-wavelength laser pulses induced modification in 10x(Al/Ti)/Si multilayer system" in Applied Surface Science, 360 (2016):559-565,
https://doi.org/10.1016/j.apsusc.2015.10.203 . .

TY  - JOUR
AU  - Salatić, Branislav
AU  - Petrović, Suzana
AU  - Peruško, Davor
AU  - Čekada, Miha
AU  - Jelenković, Branislav
AU  - Pantelić, Dejan
PY  - 2016
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/1108
AB  - A study of the effects of laser irradiation on the morphology and composition of Ni/Ti multilayers induced by nanosecond laser pulses at different wavelengths is reported. Irradiation of complex 109(Ni/Ti)/Si sample was done by a Nd:YAG laser which operate at a 1064 nm wavelength, frequency doubled wavelength (532 nm) and dual-wavelength (1064 and 532 nm). The following surface morphological changes were observed: (1) ablation of the thin film during the first laser pulse and (2) appearance of some nanostructures (mosaic structure) in the irradiated region. After action of one pulse, the boundary of damage area was relatively sharp at low pulse energy, whereas it was diffuse after irradiation with higher energy per pulse. The results obtained show that laser irradiation induced mixing between Ni and Ti layers which creates conditions for the formation of intermetallic compounds. A numerical model was used to predict ablation depths and temperatures inside the material during the time. The model prediction shows a close agreement with experimental data.
T2  - Optical and Quantum Electronics
T1  - Laser irradiation of 10x(Ni/Ti)/Si multilayers at different wavelengths
VL  - 48
IS  - 6
DO  - 10.1007/s11082-016-0503-4
ER  - 

@article{
author = "Salatić, Branislav and Petrović, Suzana and Peruško, Davor and Čekada, Miha and Jelenković, Branislav and Pantelić, Dejan",
year = "2016",
abstract = "A study of the effects of laser irradiation on the morphology and composition of Ni/Ti multilayers induced by nanosecond laser pulses at different wavelengths is reported. Irradiation of complex 109(Ni/Ti)/Si sample was done by a Nd:YAG laser which operate at a 1064 nm wavelength, frequency doubled wavelength (532 nm) and dual-wavelength (1064 and 532 nm). The following surface morphological changes were observed: (1) ablation of the thin film during the first laser pulse and (2) appearance of some nanostructures (mosaic structure) in the irradiated region. After action of one pulse, the boundary of damage area was relatively sharp at low pulse energy, whereas it was diffuse after irradiation with higher energy per pulse. The results obtained show that laser irradiation induced mixing between Ni and Ti layers which creates conditions for the formation of intermetallic compounds. A numerical model was used to predict ablation depths and temperatures inside the material during the time. The model prediction shows a close agreement with experimental data.",
journal = "Optical and Quantum Electronics",
title = "Laser irradiation of 10x(Ni/Ti)/Si multilayers at different wavelengths",
volume = "48",
number = "6",
doi = "10.1007/s11082-016-0503-4"
}

Salatić, B., Petrović, S., Peruško, D., Čekada, M., Jelenković, B.,& Pantelić, D.. (2016). Laser irradiation of 10x(Ni/Ti)/Si multilayers at different wavelengths. in Optical and Quantum Electronics, 48(6).
https://doi.org/10.1007/s11082-016-0503-4

Salatić B, Petrović S, Peruško D, Čekada M, Jelenković B, Pantelić D. Laser irradiation of 10x(Ni/Ti)/Si multilayers at different wavelengths. in Optical and Quantum Electronics. 2016;48(6).
doi:10.1007/s11082-016-0503-4 .

Salatić, Branislav, Petrović, Suzana, Peruško, Davor, Čekada, Miha, Jelenković, Branislav, Pantelić, Dejan, "Laser irradiation of 10x(Ni/Ti)/Si multilayers at different wavelengths" in Optical and Quantum Electronics, 48, no. 6 (2016),
https://doi.org/10.1007/s11082-016-0503-4 . .

TY  - JOUR
AU  - Petrović, Suzana
AU  - Gaković, Biljana M.
AU  - Peruško, Davor
AU  - Stratakis, Emmanuel
AU  - Bogdanović-Radović, Ivančica
AU  - Čekada, Miha
AU  - Fotakis, C.
AU  - Jelenković, Branislav
PY  - 2013
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/5819
AB  - Laser-induced periodic surface structures (LIPSSs) and chemical composition changes of Ti-based nanolayered thin films (Al/Ti, Ni/Ti) after femtosecond (fs) laser pulses action were studied. Irradiation is performed using linearly polarized Ti:Sapphire fs laser pulses of 40 fs pulse duration and 800 nm wavelength. The low spatial frequency LIPSS (LSFL), oriented perpendicular to the laser polarization with periods slightly lower than the irradiation wavelength, was typically formed at elevated laser fluences. On the contrary, high spatial frequency LIPSS (HSFL) with uniform period of 155 nm, parallel to the laser light polarization, appeared at low laser fluences, as well as in the wings of the Gaussian laser beam distribution for higher used fluence. LSFL formation was associated with the material ablation process and accompanied by the intense formation of nanoparticles, especially in the Ni/Ti system. The composition changes at the surface of both multilayer systems in the LSFL area indicated the intermixing between layers and the substrate. Concentration and distribution of all constitutive elements in the irradiated area with formed HSFLs were almost unchanged. (C) 2013 AIP Publishing LLC.
T2  - Journal of Applied Physics
T1  - Femtosecond laser-induced periodic surface structure on the Ti-based nanolayered thin films
VL  - 114
IS  - 23
DO  - 10.1063/1.4848016
ER  - 

@article{
author = "Petrović, Suzana and Gaković, Biljana M. and Peruško, Davor and Stratakis, Emmanuel and Bogdanović-Radović, Ivančica and Čekada, Miha and Fotakis, C. and Jelenković, Branislav",
year = "2013",
abstract = "Laser-induced periodic surface structures (LIPSSs) and chemical composition changes of Ti-based nanolayered thin films (Al/Ti, Ni/Ti) after femtosecond (fs) laser pulses action were studied. Irradiation is performed using linearly polarized Ti:Sapphire fs laser pulses of 40 fs pulse duration and 800 nm wavelength. The low spatial frequency LIPSS (LSFL), oriented perpendicular to the laser polarization with periods slightly lower than the irradiation wavelength, was typically formed at elevated laser fluences. On the contrary, high spatial frequency LIPSS (HSFL) with uniform period of 155 nm, parallel to the laser light polarization, appeared at low laser fluences, as well as in the wings of the Gaussian laser beam distribution for higher used fluence. LSFL formation was associated with the material ablation process and accompanied by the intense formation of nanoparticles, especially in the Ni/Ti system. The composition changes at the surface of both multilayer systems in the LSFL area indicated the intermixing between layers and the substrate. Concentration and distribution of all constitutive elements in the irradiated area with formed HSFLs were almost unchanged. (C) 2013 AIP Publishing LLC.",
journal = "Journal of Applied Physics",
title = "Femtosecond laser-induced periodic surface structure on the Ti-based nanolayered thin films",
volume = "114",
number = "23",
doi = "10.1063/1.4848016"
}

Petrović, S., Gaković, B. M., Peruško, D., Stratakis, E., Bogdanović-Radović, I., Čekada, M., Fotakis, C.,& Jelenković, B.. (2013). Femtosecond laser-induced periodic surface structure on the Ti-based nanolayered thin films. in Journal of Applied Physics, 114(23).
https://doi.org/10.1063/1.4848016

Petrović S, Gaković BM, Peruško D, Stratakis E, Bogdanović-Radović I, Čekada M, Fotakis C, Jelenković B. Femtosecond laser-induced periodic surface structure on the Ti-based nanolayered thin films. in Journal of Applied Physics. 2013;114(23).
doi:10.1063/1.4848016 .

Petrović, Suzana, Gaković, Biljana M., Peruško, Davor, Stratakis, Emmanuel, Bogdanović-Radović, Ivančica, Čekada, Miha, Fotakis, C., Jelenković, Branislav, "Femtosecond laser-induced periodic surface structure on the Ti-based nanolayered thin films" in Journal of Applied Physics, 114, no. 23 (2013),
https://doi.org/10.1063/1.4848016 . .

TY  - JOUR
AU  - Petrović, Suzana
AU  - Salatić, Branislav
AU  - Peruško, Davor
AU  - Panjan, Matjaž
AU  - Čekada, Miha
AU  - Gaković, Biljana M.
AU  - Jelenković, Branislav
AU  - Trtica, Milan
PY  - 2012
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/6956
AB  - A study of the effects of laser irradiation on the morphology and structure of Al/Ti and Ni/Ti multilayers is reported in this paper. Multilayers of Al/Ti and Ni/Ti were deposited by dc ion sputtering on Si(100) substrates in a single vacuum run. Laser processing was done by a focused Er, Yb, Cr glass laser beam at a wavelength of 1540 nm, a pulse duration of 40 ns and fluence in the range 8.5-23.8 J cm(-2). Surface changes can be summarized as follows: (i) the intensive removal of surface material with crater-like characteristics, (ii) the appearance of hydrodynamic features (such as resolidified droplets) and (iii) the sporadic appearance of cracking. Changes in the (Ni/Ti)/Si system included modification of the Si substrate with the formation of polygonal-mosaic structures and the appearance of hydrodynamic features in the form of nano-globules. The rate of ablation increased with energy density, whereas the rate of ablation for the (Ni/Ti)/Si system (similar to 11 x 10(3) mu m(3) per pulse) was higher than that for the (Al/Ti)/Si system (similar to 7 x 10(3) mu m(3) per pulse).
T2  - Physica Scripta
T1  - Surface modification of Ti-based nanocomposite multilayer structures by using laser beam irradiation
VL  - T149
DO  - 10.1088/0031-8949/2012/T149/014082
ER  - 

@article{
author = "Petrović, Suzana and Salatić, Branislav and Peruško, Davor and Panjan, Matjaž and Čekada, Miha and Gaković, Biljana M. and Jelenković, Branislav and Trtica, Milan",
year = "2012",
abstract = "A study of the effects of laser irradiation on the morphology and structure of Al/Ti and Ni/Ti multilayers is reported in this paper. Multilayers of Al/Ti and Ni/Ti were deposited by dc ion sputtering on Si(100) substrates in a single vacuum run. Laser processing was done by a focused Er, Yb, Cr glass laser beam at a wavelength of 1540 nm, a pulse duration of 40 ns and fluence in the range 8.5-23.8 J cm(-2). Surface changes can be summarized as follows: (i) the intensive removal of surface material with crater-like characteristics, (ii) the appearance of hydrodynamic features (such as resolidified droplets) and (iii) the sporadic appearance of cracking. Changes in the (Ni/Ti)/Si system included modification of the Si substrate with the formation of polygonal-mosaic structures and the appearance of hydrodynamic features in the form of nano-globules. The rate of ablation increased with energy density, whereas the rate of ablation for the (Ni/Ti)/Si system (similar to 11 x 10(3) mu m(3) per pulse) was higher than that for the (Al/Ti)/Si system (similar to 7 x 10(3) mu m(3) per pulse).",
journal = "Physica Scripta",
title = "Surface modification of Ti-based nanocomposite multilayer structures by using laser beam irradiation",
volume = "T149",
doi = "10.1088/0031-8949/2012/T149/014082"
}

Petrović, S., Salatić, B., Peruško, D., Panjan, M., Čekada, M., Gaković, B. M., Jelenković, B.,& Trtica, M.. (2012). Surface modification of Ti-based nanocomposite multilayer structures by using laser beam irradiation. in Physica Scripta, T149.
https://doi.org/10.1088/0031-8949/2012/T149/014082

Petrović S, Salatić B, Peruško D, Panjan M, Čekada M, Gaković BM, Jelenković B, Trtica M. Surface modification of Ti-based nanocomposite multilayer structures by using laser beam irradiation. in Physica Scripta. 2012;T149.
doi:10.1088/0031-8949/2012/T149/014082 .

Petrović, Suzana, Salatić, Branislav, Peruško, Davor, Panjan, Matjaž, Čekada, Miha, Gaković, Biljana M., Jelenković, Branislav, Trtica, Milan, "Surface modification of Ti-based nanocomposite multilayer structures by using laser beam irradiation" in Physica Scripta, T149 (2012),
https://doi.org/10.1088/0031-8949/2012/T149/014082 . .

TY  - JOUR
AU  - Petrović, Suzana
AU  - Peruško, Davor
AU  - Radović-Bogdanović, I.
AU  - Branković, Goran O.
AU  - Čekada, Miha
AU  - Gaković, Biljana M.
AU  - Jaksic, M.
AU  - Trtica, Milan
AU  - Milosavljević, Momir
PY  - 2012
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/4912
AB  - In this work we studied the influence of laser radiation on the composition, structure and morphology of WTi thin films deposited on n-type (100) silicon wafers. The films were deposited by d.c. sputtering from a 70:30 at% W-Ti target, using Ar ions, to a thickness of similar to 190 nm. Irradiation was performed with a pulsed Nd:YAG laser operating at 1064 nm, whereas the pulse duration was 150 ps. Laser fluences of 3.2 and 5.9 J/cm(2) were found to be sufficient for modification of the WTi/silicon target system. The results show: (i) ablation of WTi thin film and a Si substrate in the central zone of spots, (ii) appearance of hydrodynamic features like resolidified material, (iii) partial ablation of the WTi thin film at the periphery and (iv) appearance of thin film cracks at the far periphery. On the non-ablated areas, the laser modification induced changes in composition, such as inter-mixing of components at the WTi/Si interface with formation of silicides in both metals. Surface oxidation was the dominant process in the ablated areas, which is demonstrated by the presence of a SiO2 phase.
T2  - Metals and Materials International
T1  - Evaluation of the composition and morphology of a WTi/Si system processed by a picosecond laser
VL  - 18
IS  - 3
SP  - 457
EP  - 463
DO  - 10.1007/s12540-012-3012-4
ER  - 

@article{
author = "Petrović, Suzana and Peruško, Davor and Radović-Bogdanović, I. and Branković, Goran O. and Čekada, Miha and Gaković, Biljana M. and Jaksic, M. and Trtica, Milan and Milosavljević, Momir",
year = "2012",
abstract = "In this work we studied the influence of laser radiation on the composition, structure and morphology of WTi thin films deposited on n-type (100) silicon wafers. The films were deposited by d.c. sputtering from a 70:30 at% W-Ti target, using Ar ions, to a thickness of similar to 190 nm. Irradiation was performed with a pulsed Nd:YAG laser operating at 1064 nm, whereas the pulse duration was 150 ps. Laser fluences of 3.2 and 5.9 J/cm(2) were found to be sufficient for modification of the WTi/silicon target system. The results show: (i) ablation of WTi thin film and a Si substrate in the central zone of spots, (ii) appearance of hydrodynamic features like resolidified material, (iii) partial ablation of the WTi thin film at the periphery and (iv) appearance of thin film cracks at the far periphery. On the non-ablated areas, the laser modification induced changes in composition, such as inter-mixing of components at the WTi/Si interface with formation of silicides in both metals. Surface oxidation was the dominant process in the ablated areas, which is demonstrated by the presence of a SiO2 phase.",
journal = "Metals and Materials International",
title = "Evaluation of the composition and morphology of a WTi/Si system processed by a picosecond laser",
volume = "18",
number = "3",
pages = "457-463",
doi = "10.1007/s12540-012-3012-4"
}

Petrović, S., Peruško, D., Radović-Bogdanović, I., Branković, G. O., Čekada, M., Gaković, B. M., Jaksic, M., Trtica, M.,& Milosavljević, M.. (2012). Evaluation of the composition and morphology of a WTi/Si system processed by a picosecond laser. in Metals and Materials International, 18(3), 457-463.
https://doi.org/10.1007/s12540-012-3012-4

Petrović S, Peruško D, Radović-Bogdanović I, Branković GO, Čekada M, Gaković BM, Jaksic M, Trtica M, Milosavljević M. Evaluation of the composition and morphology of a WTi/Si system processed by a picosecond laser. in Metals and Materials International. 2012;18(3):457-463.
doi:10.1007/s12540-012-3012-4 .

Petrović, Suzana, Peruško, Davor, Radović-Bogdanović, I., Branković, Goran O., Čekada, Miha, Gaković, Biljana M., Jaksic, M., Trtica, Milan, Milosavljević, Momir, "Evaluation of the composition and morphology of a WTi/Si system processed by a picosecond laser" in Metals and Materials International, 18, no. 3 (2012):457-463,
https://doi.org/10.1007/s12540-012-3012-4 . .

TY  - JOUR
AU  - Petrović, Suzana
AU  - Peruško, Davor
AU  - Milovanović, Dubravka S.
AU  - Kovač, Janez
AU  - Čekada, Miha
AU  - Panjan, Peter
AU  - Gaković, Biljana M.
AU  - Trtica, Milan
PY  - 2010
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/4044
AB  - A study of morphological and composition changes of the WTi/Si system induced by nanosecond and picosecond laser pulses is presented. A 190 nm thick WTi film was deposited on a silicon substrate of n-type (100). The pulsed laser systems used were: nanosecond TEA CO(2) laser (emission, 10.6 mu m; pulse FWHM; pulse duration 120 ns) and picosecond Nd:YAG laser (emission, 532 nm; pulse FWHM; pulse duration 40 ps). During experiments the used fluences (Phi) had similar values, Phi(1) = 20 J cm(-2) in case of the TEA CO(2) laser and Phi(2) = 16 J cm(-2) for the Nd: YAG laser. The laser-induced morphological and composition modifications showed a dependence on pulse duration. Generally, the following morphological changes were observed: (i) ablation/exfoliation of the WTi thin film, (ii) appearance of hydrodynamic features such as resolidified material, and (iii) formation of nano-sized grains and globules. Overall morphological modifications were more pronounced after the picosecond laser action. The surface composition analysis showed a quite different distribution of sample components depending on the pulse duration. Formation of the silicon dioxide (SiO(2)) was recorded only in the case of irradiation of the WTi/Si system by picosecond laser pulses.
T2  - Journal of Optics
T1  - Effects of the pulse duration in laser modification of nano-sized WTi film on Si substrate
VL  - 12
IS  - 7
DO  - 10.1088/2040-8978/12/7/075602
ER  - 

@article{
author = "Petrović, Suzana and Peruško, Davor and Milovanović, Dubravka S. and Kovač, Janez and Čekada, Miha and Panjan, Peter and Gaković, Biljana M. and Trtica, Milan",
year = "2010",
abstract = "A study of morphological and composition changes of the WTi/Si system induced by nanosecond and picosecond laser pulses is presented. A 190 nm thick WTi film was deposited on a silicon substrate of n-type (100). The pulsed laser systems used were: nanosecond TEA CO(2) laser (emission, 10.6 mu m; pulse FWHM; pulse duration 120 ns) and picosecond Nd:YAG laser (emission, 532 nm; pulse FWHM; pulse duration 40 ps). During experiments the used fluences (Phi) had similar values, Phi(1) = 20 J cm(-2) in case of the TEA CO(2) laser and Phi(2) = 16 J cm(-2) for the Nd: YAG laser. The laser-induced morphological and composition modifications showed a dependence on pulse duration. Generally, the following morphological changes were observed: (i) ablation/exfoliation of the WTi thin film, (ii) appearance of hydrodynamic features such as resolidified material, and (iii) formation of nano-sized grains and globules. Overall morphological modifications were more pronounced after the picosecond laser action. The surface composition analysis showed a quite different distribution of sample components depending on the pulse duration. Formation of the silicon dioxide (SiO(2)) was recorded only in the case of irradiation of the WTi/Si system by picosecond laser pulses.",
journal = "Journal of Optics",
title = "Effects of the pulse duration in laser modification of nano-sized WTi film on Si substrate",
volume = "12",
number = "7",
doi = "10.1088/2040-8978/12/7/075602"
}

Petrović, S., Peruško, D., Milovanović, D. S., Kovač, J., Čekada, M., Panjan, P., Gaković, B. M.,& Trtica, M.. (2010). Effects of the pulse duration in laser modification of nano-sized WTi film on Si substrate. in Journal of Optics, 12(7).
https://doi.org/10.1088/2040-8978/12/7/075602

Petrović S, Peruško D, Milovanović DS, Kovač J, Čekada M, Panjan P, Gaković BM, Trtica M. Effects of the pulse duration in laser modification of nano-sized WTi film on Si substrate. in Journal of Optics. 2010;12(7).
doi:10.1088/2040-8978/12/7/075602 .

Petrović, Suzana, Peruško, Davor, Milovanović, Dubravka S., Kovač, Janez, Čekada, Miha, Panjan, Peter, Gaković, Biljana M., Trtica, Milan, "Effects of the pulse duration in laser modification of nano-sized WTi film on Si substrate" in Journal of Optics, 12, no. 7 (2010),
https://doi.org/10.1088/2040-8978/12/7/075602 . .

TY  - JOUR
AU  - Petrović, Suzana
AU  - Gaković, Biljana M.
AU  - Peruško, Davor
AU  - Desai, T.
AU  - Batani, Dimitri
AU  - Čekada, Miha
AU  - Radak, Bojan
AU  - Trtica, Milan
PY  - 2009
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/3773
AB  - Interaction of an Nd:YAG laser, operating at 532 nm wavelength and pulse duration of 40 ps, with tungsten-titanium (WTi) thin film (thickness, 190 nm) deposited on single silicon (100) substrate was studied. Laser fluences of 10.5 and 13.4 J/cm(2) were found to be sufficient for modification of the WTi/silicon target system. The energy absorbed from the Nd:YAG laser beam is partially converted to thermal energy, which generates a series of effects, such as melting, vaporization of the molten material, shock waves, etc. The following WTi/silicon surface morphological changes were observed: (i) ablation of the thin film during the first laser pulse. The boundary of damage area was relatively sharp after action of one pulse whereas it was quite diffuse after irradiation with more than 10 pulses; (ii) appearance of some nano-structures (e.g., nano-ripples) in the irradiated region; (iii) appearance of the micro-cracking. The process of the laser interaction with WTi/silicon target was accompanied by formation of plasma.
T2  - Laser Physics
T1  - Picosecond laser ablation of nano-sized WTi thin film
VL  - 19
IS  - 8
SP  - 1844
EP  - 1849
DO  - 10.1134/S1054660X09150353
ER  - 

@article{
author = "Petrović, Suzana and Gaković, Biljana M. and Peruško, Davor and Desai, T. and Batani, Dimitri and Čekada, Miha and Radak, Bojan and Trtica, Milan",
year = "2009",
abstract = "Interaction of an Nd:YAG laser, operating at 532 nm wavelength and pulse duration of 40 ps, with tungsten-titanium (WTi) thin film (thickness, 190 nm) deposited on single silicon (100) substrate was studied. Laser fluences of 10.5 and 13.4 J/cm(2) were found to be sufficient for modification of the WTi/silicon target system. The energy absorbed from the Nd:YAG laser beam is partially converted to thermal energy, which generates a series of effects, such as melting, vaporization of the molten material, shock waves, etc. The following WTi/silicon surface morphological changes were observed: (i) ablation of the thin film during the first laser pulse. The boundary of damage area was relatively sharp after action of one pulse whereas it was quite diffuse after irradiation with more than 10 pulses; (ii) appearance of some nano-structures (e.g., nano-ripples) in the irradiated region; (iii) appearance of the micro-cracking. The process of the laser interaction with WTi/silicon target was accompanied by formation of plasma.",
journal = "Laser Physics",
title = "Picosecond laser ablation of nano-sized WTi thin film",
volume = "19",
number = "8",
pages = "1844-1849",
doi = "10.1134/S1054660X09150353"
}

Petrović, S., Gaković, B. M., Peruško, D., Desai, T., Batani, D., Čekada, M., Radak, B.,& Trtica, M.. (2009). Picosecond laser ablation of nano-sized WTi thin film. in Laser Physics, 19(8), 1844-1849.
https://doi.org/10.1134/S1054660X09150353

Petrović S, Gaković BM, Peruško D, Desai T, Batani D, Čekada M, Radak B, Trtica M. Picosecond laser ablation of nano-sized WTi thin film. in Laser Physics. 2009;19(8):1844-1849.
doi:10.1134/S1054660X09150353 .

Petrović, Suzana, Gaković, Biljana M., Peruško, Davor, Desai, T., Batani, Dimitri, Čekada, Miha, Radak, Bojan, Trtica, Milan, "Picosecond laser ablation of nano-sized WTi thin film" in Laser Physics, 19, no. 8 (2009):1844-1849,
https://doi.org/10.1134/S1054660X09150353 . .

TY  - JOUR
AU  - Gaković, Biljana M.
AU  - Trtica, Milan
AU  - Radak, Bojan
AU  - Petrović, Suzana
AU  - Panjan, Peter
AU  - Čekada, Miha
AU  - Desai, T.
AU  - Batani, Dimitri
PY  - 2009
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/3615
AB  - A multilayered TiAlN/TiN coating deposited on H11 work-steel was irradiated by a TEA CO(2) laser (ns pulses) and a Nd:YAG laser (ps pulses), and the effects compared. The coating was 2.17 mu m thick and consisted of 45 layers. The laser-induced modifications showed dependence on laser pulse duration, pulse count and laser wavelength. The conditions for coating ablation in both cases were determined. The experiment has revealed laser-induced periodic surface structures (LPSS) on nanometre and micrometre scales, depending on the laser wavelength used. Sample surfaces were characterized before and after laser irradiation by an optical microscope, scanning electron microscope (SEM), focused ion beam (FIB) microscope and profilometry.
T2  - Journal of Optics. A: Pure and Applied Optics
T1  - Modification of multilayered TiAlN/TiN coating by nanosecond and picosecond laser pulses
VL  - 11
IS  - 1
DO  - 10.1088/1464-4258/11/1/015601
ER  - 

@article{
author = "Gaković, Biljana M. and Trtica, Milan and Radak, Bojan and Petrović, Suzana and Panjan, Peter and Čekada, Miha and Desai, T. and Batani, Dimitri",
year = "2009",
abstract = "A multilayered TiAlN/TiN coating deposited on H11 work-steel was irradiated by a TEA CO(2) laser (ns pulses) and a Nd:YAG laser (ps pulses), and the effects compared. The coating was 2.17 mu m thick and consisted of 45 layers. The laser-induced modifications showed dependence on laser pulse duration, pulse count and laser wavelength. The conditions for coating ablation in both cases were determined. The experiment has revealed laser-induced periodic surface structures (LPSS) on nanometre and micrometre scales, depending on the laser wavelength used. Sample surfaces were characterized before and after laser irradiation by an optical microscope, scanning electron microscope (SEM), focused ion beam (FIB) microscope and profilometry.",
journal = "Journal of Optics. A: Pure and Applied Optics",
title = "Modification of multilayered TiAlN/TiN coating by nanosecond and picosecond laser pulses",
volume = "11",
number = "1",
doi = "10.1088/1464-4258/11/1/015601"
}

Gaković, B. M., Trtica, M., Radak, B., Petrović, S., Panjan, P., Čekada, M., Desai, T.,& Batani, D.. (2009). Modification of multilayered TiAlN/TiN coating by nanosecond and picosecond laser pulses. in Journal of Optics. A: Pure and Applied Optics, 11(1).
https://doi.org/10.1088/1464-4258/11/1/015601

Gaković BM, Trtica M, Radak B, Petrović S, Panjan P, Čekada M, Desai T, Batani D. Modification of multilayered TiAlN/TiN coating by nanosecond and picosecond laser pulses. in Journal of Optics. A: Pure and Applied Optics. 2009;11(1).
doi:10.1088/1464-4258/11/1/015601 .

Gaković, Biljana M., Trtica, Milan, Radak, Bojan, Petrović, Suzana, Panjan, Peter, Čekada, Miha, Desai, T., Batani, Dimitri, "Modification of multilayered TiAlN/TiN coating by nanosecond and picosecond laser pulses" in Journal of Optics. A: Pure and Applied Optics, 11, no. 1 (2009),
https://doi.org/10.1088/1464-4258/11/1/015601 . .