TY  - JOUR
AU  - Novaković, Mirjana M.
AU  - Popović, Maja
AU  - Zhang, Kun
AU  - Rakočević, Zlatko Lj.
AU  - Bibić, Nataša M.
PY  - 2016
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/1350
AB  - Modification in structural and optical properties of chromium-nitride (CrN) films induced by argon ion irradiation and thermal annealings were investigated using various experimental techniques. CrN films deposited by d.c. reactive sputtering on Si substrate were implanted with 200 keV argon ions, at fluences of 5-20 x 10(15) ions/cm(2). As-implanted samples were then annealed in vacuum, for 2 h at 700 degrees C. Rutherford backscattering spectrometry, X-ray diffraction, cross-sectional (high-resolution) transmission electron microscopy and spectroscopic ellipsometry (SE) measurements were carried out in order to study structural and optical properties of the layers. After irradiation with 200 keV Ar ions a damaged surface layer of nanocrystalline structure was generated, which extended beyond the implantation profile, but left an undamaged bottom zone. Partial loss of columnar structure observed in implanted samples was recovered after annealing at 700 degrees C and CrN started to decompose to Cr2N. This layer geometry determined from transmission electron microscopy was inferred in the analysis of SE data using the combined Drude and Tauc-Lorentz model, and the variation of the optical bandgap was deduced. The results are discussed on the basis of the changes induced in the microstructure. It was found that the optical properties of the layers are strongly dependent on the defects concentration of CrN. (C) 2016 Elsevier B.V. All rights reserved.
T2  - Optical Materials
T1  - Effects of 200 keV Ar-ions irradiation on the structural and optical properties of reactively sputtered CrN films
VL  - 62
SP  - 57
EP  - 63
DO  - 10.1016/j.optmat.2016.09.047
ER  - 

@article{
author = "Novaković, Mirjana M. and Popović, Maja and Zhang, Kun and Rakočević, Zlatko Lj. and Bibić, Nataša M.",
year = "2016",
abstract = "Modification in structural and optical properties of chromium-nitride (CrN) films induced by argon ion irradiation and thermal annealings were investigated using various experimental techniques. CrN films deposited by d.c. reactive sputtering on Si substrate were implanted with 200 keV argon ions, at fluences of 5-20 x 10(15) ions/cm(2). As-implanted samples were then annealed in vacuum, for 2 h at 700 degrees C. Rutherford backscattering spectrometry, X-ray diffraction, cross-sectional (high-resolution) transmission electron microscopy and spectroscopic ellipsometry (SE) measurements were carried out in order to study structural and optical properties of the layers. After irradiation with 200 keV Ar ions a damaged surface layer of nanocrystalline structure was generated, which extended beyond the implantation profile, but left an undamaged bottom zone. Partial loss of columnar structure observed in implanted samples was recovered after annealing at 700 degrees C and CrN started to decompose to Cr2N. This layer geometry determined from transmission electron microscopy was inferred in the analysis of SE data using the combined Drude and Tauc-Lorentz model, and the variation of the optical bandgap was deduced. The results are discussed on the basis of the changes induced in the microstructure. It was found that the optical properties of the layers are strongly dependent on the defects concentration of CrN. (C) 2016 Elsevier B.V. All rights reserved.",
journal = "Optical Materials",
title = "Effects of 200 keV Ar-ions irradiation on the structural and optical properties of reactively sputtered CrN films",
volume = "62",
pages = "57-63",
doi = "10.1016/j.optmat.2016.09.047"
}

Novaković, M. M., Popović, M., Zhang, K., Rakočević, Z. Lj.,& Bibić, N. M.. (2016). Effects of 200 keV Ar-ions irradiation on the structural and optical properties of reactively sputtered CrN films. in Optical Materials, 62, 57-63.
https://doi.org/10.1016/j.optmat.2016.09.047

Novaković MM, Popović M, Zhang K, Rakočević ZL, Bibić NM. Effects of 200 keV Ar-ions irradiation on the structural and optical properties of reactively sputtered CrN films. in Optical Materials. 2016;62:57-63.
doi:10.1016/j.optmat.2016.09.047 .

Novaković, Mirjana M., Popović, Maja, Zhang, Kun, Rakočević, Zlatko Lj., Bibić, Nataša M., "Effects of 200 keV Ar-ions irradiation on the structural and optical properties of reactively sputtered CrN films" in Optical Materials, 62 (2016):57-63,
https://doi.org/10.1016/j.optmat.2016.09.047 . .

TY  - JOUR
AU  - Popović, Maja
AU  - Novaković, Mirjana M.
AU  - Bibić, Nataša M.
PY  - 2015
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/919
AB  - The structure, absorption coefficient and electrical resistivity studies on TiN thin films are presented. The film of thickness 240 nm was grown on Si (100) substrate by DC reactive sputtering at an average deposition rate of similar to 8 nm/min. After deposition the samples were annealed for 1 h at 600 degrees C and 2 h at 700 degrees C in nitrogen ambient and vacuum furnace, respectively. Structural characterizations were performed by Rutherford backscattering spectrometry (RBS), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The optical properties were investigated by spectroscopic ellipsometry while a four point probe was used for electrical characterization. It was found that the post-deposition annealing of the films did not cause any variation in stoichiometry, but strongly affects the structural parameters such as lattice constant, micro-strain and grain size. The observed increase in the grain size after annealing leads to significantly lower value of the coefficient of absorption. These changes could be directly correlated with variation of electrical properties of TiN thin films.
T2  - Processing and Application of Ceramics
T1  - Annealing effects on the properties of TiN thin films
VL  - 9
IS  - 2
SP  - 67
EP  - 71
DO  - 10.2298/PAC1502067P
ER  - 

@article{
author = "Popović, Maja and Novaković, Mirjana M. and Bibić, Nataša M.",
year = "2015",
abstract = "The structure, absorption coefficient and electrical resistivity studies on TiN thin films are presented. The film of thickness 240 nm was grown on Si (100) substrate by DC reactive sputtering at an average deposition rate of similar to 8 nm/min. After deposition the samples were annealed for 1 h at 600 degrees C and 2 h at 700 degrees C in nitrogen ambient and vacuum furnace, respectively. Structural characterizations were performed by Rutherford backscattering spectrometry (RBS), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The optical properties were investigated by spectroscopic ellipsometry while a four point probe was used for electrical characterization. It was found that the post-deposition annealing of the films did not cause any variation in stoichiometry, but strongly affects the structural parameters such as lattice constant, micro-strain and grain size. The observed increase in the grain size after annealing leads to significantly lower value of the coefficient of absorption. These changes could be directly correlated with variation of electrical properties of TiN thin films.",
journal = "Processing and Application of Ceramics",
title = "Annealing effects on the properties of TiN thin films",
volume = "9",
number = "2",
pages = "67-71",
doi = "10.2298/PAC1502067P"
}

Popović, M., Novaković, M. M.,& Bibić, N. M.. (2015). Annealing effects on the properties of TiN thin films. in Processing and Application of Ceramics, 9(2), 67-71.
https://doi.org/10.2298/PAC1502067P

Popović M, Novaković MM, Bibić NM. Annealing effects on the properties of TiN thin films. in Processing and Application of Ceramics. 2015;9(2):67-71.
doi:10.2298/PAC1502067P .

Popović, Maja, Novaković, Mirjana M., Bibić, Nataša M., "Annealing effects on the properties of TiN thin films" in Processing and Application of Ceramics, 9, no. 2 (2015):67-71,
https://doi.org/10.2298/PAC1502067P . .

TY  - JOUR
AU  - Novaković, Mirjana M.
AU  - Popović, Maja
AU  - Bibić, Nataša M.
PY  - 2015
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/728
AB  - The present study deals with CrN films irradiated at room temperature (RT) with 200 keV Ar+ ions. The CrN layers were deposited by d.c. reactive sputtering on Si (100) wafers, at nitrogen partial pressure of 5x10(-4) mbar, to a total thickness of 280 nm. The substrates were held at 150 degrees C during deposition. After deposition the CrN layers were irradiated with 200 keV Ar+ ions to the fluences of 5x10(15) - 2x10(16) ions/cm(2). Structural characterization was performed with Rutherford backscattering spectroscopy (RBS), cross-sectional transmission electron microscopy (XTEM) and X-ray diffraction (XRD). Spectroscopic ellipsometry measurements were carried out in order to study optical properties of the samples. The irradiations caused the microstructrual changes in CrN layers, but no amorphization even at the highest argon fluence of 2x10(16) ions/cm(2). Observed changes in microstructure were correlated with the variation in optical parameters. It was found that both refractive index and extinction coefficient are strongly dependent on the defect concentration in CrN layers.
T2  - Science of Sintering
T1  - Argon Irradiation Effects on the Structural and Optical Properties of Reactively Sputtered CrN Films
VL  - 47
IS  - 2
SP  - 187
EP  - 194
DO  - 10.2298/SOS1502187N
ER  - 

@article{
author = "Novaković, Mirjana M. and Popović, Maja and Bibić, Nataša M.",
year = "2015",
abstract = "The present study deals with CrN films irradiated at room temperature (RT) with 200 keV Ar+ ions. The CrN layers were deposited by d.c. reactive sputtering on Si (100) wafers, at nitrogen partial pressure of 5x10(-4) mbar, to a total thickness of 280 nm. The substrates were held at 150 degrees C during deposition. After deposition the CrN layers were irradiated with 200 keV Ar+ ions to the fluences of 5x10(15) - 2x10(16) ions/cm(2). Structural characterization was performed with Rutherford backscattering spectroscopy (RBS), cross-sectional transmission electron microscopy (XTEM) and X-ray diffraction (XRD). Spectroscopic ellipsometry measurements were carried out in order to study optical properties of the samples. The irradiations caused the microstructrual changes in CrN layers, but no amorphization even at the highest argon fluence of 2x10(16) ions/cm(2). Observed changes in microstructure were correlated with the variation in optical parameters. It was found that both refractive index and extinction coefficient are strongly dependent on the defect concentration in CrN layers.",
journal = "Science of Sintering",
title = "Argon Irradiation Effects on the Structural and Optical Properties of Reactively Sputtered CrN Films",
volume = "47",
number = "2",
pages = "187-194",
doi = "10.2298/SOS1502187N"
}

Novaković, M. M., Popović, M.,& Bibić, N. M.. (2015). Argon Irradiation Effects on the Structural and Optical Properties of Reactively Sputtered CrN Films. in Science of Sintering, 47(2), 187-194.
https://doi.org/10.2298/SOS1502187N

Novaković MM, Popović M, Bibić NM. Argon Irradiation Effects on the Structural and Optical Properties of Reactively Sputtered CrN Films. in Science of Sintering. 2015;47(2):187-194.
doi:10.2298/SOS1502187N .

Novaković, Mirjana M., Popović, Maja, Bibić, Nataša M., "Argon Irradiation Effects on the Structural and Optical Properties of Reactively Sputtered CrN Films" in Science of Sintering, 47, no. 2 (2015):187-194,
https://doi.org/10.2298/SOS1502187N . .

TY  - JOUR
AU  - Novaković, Mirjana M.
AU  - Popović, Maja
AU  - Zhang, Kun
AU  - Mitrić, Miodrag
AU  - Bibić, Nataša M.
PY  - 2015
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/691
AB  - Reactively sputtered CrN layer, deposited on Si(100) wafer, was implanted at room temperature with 80-keV V+. ions to the fluence of 2 x 10(17) ions/cm(2). After implantation the sample was annealed in a vacuum, for 2 h at 700 degrees C. The microstructure and chemical composition of CrN films was investigated using Rutherford backscattering spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction and cross-sectional transmission electron microscopy (conventional and high-resolution), together with fast Fourier transformation analyses. It was found that vanadium atoms are distributed in the sub-surface region of CrN layer, with the maximum concentration at similar to 20 nm. After annealing the formation of VN nanoparticles was observed. The nanoparticles are spherical shaped with a size of 8-20 nm in diameter. (C) 2015 Elsevier B.V. All rights reserved.
T2  - Nuclear Instruments and Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms
T1  - Irradiation induced formation of VN in CrN thin films
VL  - 358
SP  - 206
EP  - 209
DO  - 10.1016/j.nimb.2015.06.036
ER  - 

@article{
author = "Novaković, Mirjana M. and Popović, Maja and Zhang, Kun and Mitrić, Miodrag and Bibić, Nataša M.",
year = "2015",
abstract = "Reactively sputtered CrN layer, deposited on Si(100) wafer, was implanted at room temperature with 80-keV V+. ions to the fluence of 2 x 10(17) ions/cm(2). After implantation the sample was annealed in a vacuum, for 2 h at 700 degrees C. The microstructure and chemical composition of CrN films was investigated using Rutherford backscattering spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction and cross-sectional transmission electron microscopy (conventional and high-resolution), together with fast Fourier transformation analyses. It was found that vanadium atoms are distributed in the sub-surface region of CrN layer, with the maximum concentration at similar to 20 nm. After annealing the formation of VN nanoparticles was observed. The nanoparticles are spherical shaped with a size of 8-20 nm in diameter. (C) 2015 Elsevier B.V. All rights reserved.",
journal = "Nuclear Instruments and Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms",
title = "Irradiation induced formation of VN in CrN thin films",
volume = "358",
pages = "206-209",
doi = "10.1016/j.nimb.2015.06.036"
}

Novaković, M. M., Popović, M., Zhang, K., Mitrić, M.,& Bibić, N. M.. (2015). Irradiation induced formation of VN in CrN thin films. in Nuclear Instruments and Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms, 358, 206-209.
https://doi.org/10.1016/j.nimb.2015.06.036

Novaković MM, Popović M, Zhang K, Mitrić M, Bibić NM. Irradiation induced formation of VN in CrN thin films. in Nuclear Instruments and Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms. 2015;358:206-209.
doi:10.1016/j.nimb.2015.06.036 .

Novaković, Mirjana M., Popović, Maja, Zhang, Kun, Mitrić, Miodrag, Bibić, Nataša M., "Irradiation induced formation of VN in CrN thin films" in Nuclear Instruments and Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms, 358 (2015):206-209,
https://doi.org/10.1016/j.nimb.2015.06.036 . .

TY  - JOUR
AU  - Popović, Maja
AU  - Novaković, Mirjana M.
AU  - Mitrić, Miodrag
AU  - Zhang, Kun
AU  - Bibić, Nataša M.
PY  - 2015
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/344
AB  - Modification in structural, optical and electrical properties of titanium nitride (TiN) thin films induced by argon ion irradiation and thermal annealings was studied using various experimental techniques. TiN thin films deposited by dc reactive sputtering on Si substrate were implanted with argon ions at 200 key. As-implanted samples were annealed before or after ion irradiation at 600 degrees C and 700 degrees C, respectively. Rutherford bacicscattering spectrometry, X-ray diffraction, cross-sectional (high-resolution) transmission electron microscopy, spectroscopic ellipsometry and electrical measurements were carried out in order to study structural, optical and electrical properties of TiN/Si samples. After irradiation with 200 keV Ar ions the columnar microstructure of TiN was changed and the presence of smaller crystalline grains was observed. Partial Loss of columnar structure observed in implanted samples was completely recovered after annealing at 700 degrees C. Observed changes in microstructure induced by ion irradiation and annealings were correlated with the variation in optical parameters obtained by spectroscopic ellipsometry. It was found that both refractive index and extinction coefficient are strongly dependent on the defects concentration and size of the crystalline grains in TiN layers. (C) 2014 Elsevier Ltd. All rights reserved.
T2  - International Journal of Refractory Metals and Hard Materials
T1  - Structural, optical and electrical properties of argon implanted TiN thin films
VL  - 48
SP  - 318
EP  - 323
DO  - 10.1016/j.ijrmhm.2014.09.026
ER  - 

@article{
author = "Popović, Maja and Novaković, Mirjana M. and Mitrić, Miodrag and Zhang, Kun and Bibić, Nataša M.",
year = "2015",
abstract = "Modification in structural, optical and electrical properties of titanium nitride (TiN) thin films induced by argon ion irradiation and thermal annealings was studied using various experimental techniques. TiN thin films deposited by dc reactive sputtering on Si substrate were implanted with argon ions at 200 key. As-implanted samples were annealed before or after ion irradiation at 600 degrees C and 700 degrees C, respectively. Rutherford bacicscattering spectrometry, X-ray diffraction, cross-sectional (high-resolution) transmission electron microscopy, spectroscopic ellipsometry and electrical measurements were carried out in order to study structural, optical and electrical properties of TiN/Si samples. After irradiation with 200 keV Ar ions the columnar microstructure of TiN was changed and the presence of smaller crystalline grains was observed. Partial Loss of columnar structure observed in implanted samples was completely recovered after annealing at 700 degrees C. Observed changes in microstructure induced by ion irradiation and annealings were correlated with the variation in optical parameters obtained by spectroscopic ellipsometry. It was found that both refractive index and extinction coefficient are strongly dependent on the defects concentration and size of the crystalline grains in TiN layers. (C) 2014 Elsevier Ltd. All rights reserved.",
journal = "International Journal of Refractory Metals and Hard Materials",
title = "Structural, optical and electrical properties of argon implanted TiN thin films",
volume = "48",
pages = "318-323",
doi = "10.1016/j.ijrmhm.2014.09.026"
}

Popović, M., Novaković, M. M., Mitrić, M., Zhang, K.,& Bibić, N. M.. (2015). Structural, optical and electrical properties of argon implanted TiN thin films. in International Journal of Refractory Metals and Hard Materials, 48, 318-323.
https://doi.org/10.1016/j.ijrmhm.2014.09.026

Popović M, Novaković MM, Mitrić M, Zhang K, Bibić NM. Structural, optical and electrical properties of argon implanted TiN thin films. in International Journal of Refractory Metals and Hard Materials. 2015;48:318-323.
doi:10.1016/j.ijrmhm.2014.09.026 .

Popović, Maja, Novaković, Mirjana M., Mitrić, Miodrag, Zhang, Kun, Bibić, Nataša M., "Structural, optical and electrical properties of argon implanted TiN thin films" in International Journal of Refractory Metals and Hard Materials, 48 (2015):318-323,
https://doi.org/10.1016/j.ijrmhm.2014.09.026 . .