Oleg Milchanin - Academia.edu (original) (raw)

Papers by Oleg Milchanin

Research paper thumbnail of Radiative recombination in zinc blende ZnSe nanocrystals ion-beam synthesized in silica

Journal of Physics D: Applied Physics, 2022

Zinc selenide nanocrystals (NCs) were successfully synthesized in silicon dioxide (silica grown o... more Zinc selenide nanocrystals (NCs) were successfully synthesized in silicon dioxide (silica grown on a silicon wafer) by high-fluence implantation of Zn+ and Se+ ions with subsequent rapid thermal annealing at 1000°C for 3 min. The high crystalline quality of the zinc blende ZnSe nanoclusters was proven by transmission electron microscopy with selected area electron diffraction and Raman spectroscopy. Low-temperature photoluminescence (PL) reveals the recombination of excitons in ZnSe, what further indicates a good crystalline quality of the synthesized nanocrystals. PL analysis shows a strong coupling of phonons and excitons. The Huang−Rhys parameter of the longitudinal optical phonon in the exciton transition S is in the range of 0.6−0.7. Despite the excellent quality of the ZnSe NCs synthesized in silica, defect states inside the NCs or at the NCs/SiO2 interface with activation energies of 0.1–0.2, 0.45 and 0.67 eV play a crucial role in radiative recombination.

Research paper thumbnail of Luminescence of ZnO nanocrystals in silica synthesized by dual (Zn, O) implantation and thermal annealing

Journal of Physics D: Applied Physics, 2021

Zinc blende ZnO nanocrystals (NCs) were synthesised in amorphous silica by high-fluence dual (Zn,... more Zinc blende ZnO nanocrystals (NCs) were synthesised in amorphous silica by high-fluence dual (Zn, O) ion implantation and subsequent thermal annealing in air. We observed the formation of core/shell nanoparticles at the depth of maximum Zn concentration as a result of an incomplete oxidation process. The silica matrix with ZnO NCs exhibits an intense white-greenish emission. Low-temperature photoluminescence spectroscopy revealed various radiative recombination mechanisms in the zinc blende ZnO NCs involving intrinsic defects that act as donors and acceptors.

Research paper thumbnail of Shi Irradiation of A IIIB v Nanoparticles and (Zn)Core /(ZnO)Shell Nanostructures Ion-Beam Synthesized in Silica: Shape Elongation, Enhanced Sputtering and Photoluminescence

SSRN Electronic Journal, 2021

Till now, shape elongation phenomenon was observed predominantly for metal nanoparticles irradiat... more Till now, shape elongation phenomenon was observed predominantly for metal nanoparticles irradiated with swift heavy ions (SHI). For the first time, we report the shape elongation of InAs and Zn(core)/ZnO(shell) nanoparticles (NPs) embedded in a silica matrix and irradiated with swift Xe ions. In case of InAs NPs, SHI irradiation results in the formation of nanorods. A diversity of elongated features is observed for Zn-based NPs: chains of small ZnO clusters, elongated (Zn)core/(ZnO)shell structures and drop-like elongated Zn particles. The intense sputtering of the silicon dioxide layer due to electronic excitations has revealed for “SiO2+Zn-based NPs” composite. Photoluminescence (PL) spectroscopy reveals emission in the visible range for two types of nanocomposites before SHIs irradiation. This emission is attributed to the oxygen excess-related defect (NBOHC) as well as to the oxygen deficiency-related centres created in silica matrix during the implantation of cluster-forming ions (In + As or Zn). The intensive band in the spectral region of 2.8 – 3.1 eV is observed in PL spectrum of annealed “SiO2+InAs NPs” composite. SHI irradiation results in its quenching and formation of an asymmetrical band centred at 1.9 eV. In case of “SiO2+Zn-based NPs” composite, SHIs irradiation results in substantial increase of PL in orange spectral range. The origin of observed emission is discussed.

Research paper thumbnail of Formation of Platinum Silicide During the Rapid Thermal Processing of the System Platinum-Silicon: Microstructure and Electrophysical Characteristics

High Temperature Material Processes: An International Quarterly of High-Technology Plasma Processes, 2019

Research paper thumbnail of Reprint of “Structure and optical properties of SiO2 films with ZnSe nanocrystals formed by ion implantation”

Surface and Coatings Technology, 2019

ZnSe nanocrystals have been formed in the silicon dioxide matrix by the sequential high-fluence i... more ZnSe nanocrystals have been formed in the silicon dioxide matrix by the sequential high-fluence implantation of Zn + and Se + ions at 500°C. After implantation a part of samples was annealed at 1000°C for 3 min using rapid thermal annealing. Structural and optical properties of ZnSe/SiO 2 nano-composite films were analyzed by means of Rutherford Backscattering Spectrometry, cross-sectional Transmission Electron Microscopy, Raman scattering and photoluminescence techniques. It was shown that a sequence of implantation affects structural and optical properties of synthesized ZnSe clusters. Based on the Raman scattering and photoluminescence data the samples for which Zn ions were implanted first exhibited a better ZnSe crystalline quality than those of reverse sequence of implantation, i.e. with Se ions implanted at the beginning. The bands of blue ZnSe band edge emission and green-red ZnSe deep defect level emission were revealed in the PL spectra of the as-implanted and annealed nano-composites. The PL spectral features observed in the blue region are due to the quantum-size effects in the ZnSe nanocrystals embedded into the silicon dioxide matrix. The PL intensity ratio of the deep defect band to the near edge emission is higher in the samples first implanted with Se ions, and Zn ions implanted next. The effect of rapid thermal annealing on structural and light-emitting properties was discussed.

Research paper thumbnail of Formation of Platinum Silicide Layers During the Rapid Thermal Processing of the System Platinum-Silicon: Structural-Phase Changes

High Temperature Material Processes: An International Quarterly of High-Technology Plasma Processes, 2019

Research paper thumbnail of Optical properties of silicon nitride films formed by plasma-chemical vapor deposition

Journal of Applied Spectroscopy, 2013

The optical properties and structure of layers of silicon nitride deposited on silicon substrates... more The optical properties and structure of layers of silicon nitride deposited on silicon substrates by plasma-aided chemical vapor deposition at 300°C are studied by ellipsometry, Raman scattering, IR spectroscopy, and photoluminescence techniques. It is found that immediately after deposition the silicon nitride contains hydrogen in the form of Si-H bonds. Annealing (1100°C, 30 min) leads to dehydrogenation and densifi cation of the nitride layer. An intense Si 3 N 4 photoluminescence signal is detected in the green. Immediately after deposition the photoluminescence peak appears at 542 nm and annealing shifts it to shorter wavelengths.

Research paper thumbnail of Structural and optical properties of silicon layers with InSb and InAs nanocrystals formed by ion-beam synthesis

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2013

We have studied the formation of InSb and InAs precipitates with sizes of several nanometers in S... more We have studied the formation of InSb and InAs precipitates with sizes of several nanometers in Si and SiO 2 /Si by means of implantation of (Sb + In) or (As + In) ions with energies from 170 to 350 keV and fluencies from 2.8 to 3.5 Â 10 16 cm À2 at 500°C and subsequent annealing at 1050-1100°C for 3-30 min. RBS, TEM/TED, RS and PL techniques were employed to characterize the implanted layers. A broad band in the region of 1.2-1.6 lm has been registered in the low-temperature PL spectra of both (Sb + In) and (As + In) implanted and annealed silicon crystals. It was shown that structural and optical properties of oxidized silicon crystals strongly depend on type of implanted species in silicon crystals.

Research paper thumbnail of Structural and Luminescent Properties of Sn-Doped SiO2 Layers

Journal of Applied Spectroscopy, 2014

ABSTRACT The formation of tin nanocrystallites in a SiO2:Sn matrix using a high-dose implantation... more ABSTRACT The formation of tin nanocrystallites in a SiO2:Sn matrix using a high-dose implantation technique followed by high-temperature processing was studied. Structural phase transformations were studied by plan-view transmission electron microscopy. Optical properties of the implanted samples were investigated by photoluminescence. It was shown that annealing of the implanted SiO2 layers formed nanoprecipitates of β-Sn and caused the appearance of regions enriched in SnO2. Photoluminescence spectra of implanted and annealed samples exhibited intense emission in photon energy range 1.3-3.6 eV that was attributed to oxygen-deficit centers created in the SiO2:Sn matrix and at the nanocluster/SiO2 interface.

Research paper thumbnail of Light Emitting Single-Crystalline Silicon Wafers Implanted with V and III Group Ions

Acta Physica Polonica A, 2014

Compound semiconductor nanocrystals (InAs, InSb, GaSb) were successfully synthesized in single cr... more Compound semiconductor nanocrystals (InAs, InSb, GaSb) were successfully synthesized in single crystalline Si by high uence ion implantation at 500 • C followed by high-temperature rapid thermal annealing or conventional furnace annealing at 9001100 • C. Rutherford backscattering spectrometry, transmission electron microscopy/ transmission electron diraction, Raman scattering, and photoluminescence were employed to characterize the implanted layers. Two dierent types of the broad band emission extending over 0.751.1 eV were observed in photoluminescence spectra of annealed samples. One of the bands disappears in photoluminescence spectra of samples annealed at 1100 • C unlike the other one.

Research paper thumbnail of Identification of nickel silicide phases on a silicon surface from Raman spectra

Journal of Applied Spectroscopy, 2013

We have demonstrated the effectiveness of Raman spectroscopy for monitoring nickel silicide forma... more We have demonstrated the effectiveness of Raman spectroscopy for monitoring nickel silicide formation processes on the surface of silicon wafers, with deposition of a composite metal layer (nickel, platinum, and vanadium) under industrial process conditions in microelectronics. The observed shift of all the NiSi lines toward lower energies is associated with formation of the metastable silicide phase Ni 1-x Pt x Si, which leads to the presence of stresses in the lattice as a result of the increase in the distances between atoms.

Research paper thumbnail of Raman study of light-emitting SiNx films grown on Si by low-pressure chemical vapor deposition

Thin Solid Films, 2015

Si-rich silicon nitride (SRSN) films were deposited on Si wafers by low pressure chemical vapor d... more Si-rich silicon nitride (SRSN) films were deposited on Si wafers by low pressure chemical vapor deposition (LPCVD) technique and, subsequently, annealed at (800-1200) °C to form Si precipitates. The composition of SiN x films was measured by Rutherford backscattering spectrometry (RBS). Two sets of samples differed by the amount of excessive Si (Si exc) in silicon nitride were studied. Evolution of Si nanoclusters from amorphous to crystalline ones during high temperature treatment was examined by Raman scattering (RS) spectroscopy. The amorphous Si clusters were already revealed in as-deposited SiN x while the annealing results in their crystallization. The crystalline nanoprecipitates are only registered in nitride films after annealing at 1200 °C. A dependence of Raman scattering intensity from the Si wafer on the temperature of annealing of SiN x /Si structures was revealed. This information was used to explain the phase transformations in SRSNs during high temperature treatments. The peculiarities of photoluminescence (PL) spectra for two sets of Si-rich SiN x films are explained

Research paper thumbnail of Effects of Annealing Regims on the Structural and Optical Properties of Inas and Gasb Nanocryctals Created by Ion–Beam Synthesis in Si Matrix

We have studied the ion-beam synthesis of InAs and GaSb nanocrystals in Si by high-fluence implan... more We have studied the ion-beam synthesis of InAs and GaSb nanocrystals in Si by high-fluence implantation of (As+In) and (Ga+Sb) ions followed a thermal annealing. In order to characterize the implanted samples Rutherford backscattering spectrometry in combination with the channelling (RBS/C), transmission electron microscopy (TEM), Raman spectrometry (RS) and low-temperature photoluminescence (PL) techniques were employed. It was demonstrated that by introducing getter, varying the ion implantation temperature, ion fluences and post-implantation annealing duration and temperature it is possible to form InAs and GaSb nanocrystals in the range of sizes of (2 – 80) nm and create different types of secondary defects distribution. RS results confirm the crystalline state of the clusters in the silicon matrix after high-fluence implantation of heavy (As+In) and (Ga+Sb) ions. Significant redistribution of implanted species has been revealed after "hot" implantation and post-implan...

Research paper thumbnail of Effect of implantation and annealing regimes on ion-beam synthesis of InAs nanocrystals

Lithuanian Journal of Physics, 2009

We reported the formation of nanosized InAs crystallites in silicon wafers by means of As (245 ke... more We reported the formation of nanosized InAs crystallites in silicon wafers by means of As (245 keV, 4.1•10 16 cm −2) and In (350 keV, 3.7•10 16 cm −2) implantation. The implantation was carried out at 25 and 500 • C. In order to verify the effect of getter on precipitates growth an additional procedure was carried out for the samples implanted with As and In species at the room temperature. This procedure included the implantation of H + 2 ions with the energy of 100 keV at 1.2•10 16 cm −2. Afterwards, the samples were annealed at 900 • C for 60 min in inert ambient. In order to characterize the implanted layers, Rutherford backscattering spectrometry in combination with the channelling (RBS / C) and transmission electron microscopy (TEM) techniques were used. TEM has revealed InAs nanocrystals in implanted samples after the annealing. It has been shown that average size and size distribution of InAs clusters depend on implantation temperature and annealing duration. Significant diffusional redistribution of implanted species has been revealed after "hot" implantation and post-implantation annealing. We have suggested that it is caused by non-equilibrium diffusion. The radiation-enhanced diffusivities at "hot" implantation have been determined for the abovementioned experimental conditions.

Research paper thumbnail of Ion-Beam Synthesis of InSb Nanocrystals in Si Matrix

Advanced Materials Research, 2013

The results of structural and optical investigation of crystalline Si with embedded InSb nanocrys... more The results of structural and optical investigation of crystalline Si with embedded InSb nanocrystals are reported. These nanocrystals were synthesized in silicon matrix by means of high-fluence “hot” implantation of Sb and In ions followed by thermal treatment. TEM gives an evidence of nanocrystal formation in implanted and annealed samples as well as an existence of microtwins and dislocation-type defects and substantial residual mechanical strains. We have identified nanocrystals as InSb from RS data. Mechanical strains in “silicon – InSb nanocrystals” system have been evaluated, too.

Research paper thumbnail of Ion-beam formation of nanopores and nanoclusters in SiO2

Vacuum, 2005

We studied nanopores and nanoclusters formation in thermally oxidized silicon wafers (SiO 2 /Si) ... more We studied nanopores and nanoclusters formation in thermally oxidized silicon wafers (SiO 2 /Si) by means of ionbeam technique. RBS, SEM, TEM and TED were used to characterize the SiO 2 layers after the ion-beam processing. Nanopores were formed by high-energy Kr ions irradiation followed by chemical etching of latent tracks zones in SiO 2 matrix. Holes with diameters of 10−15nmandlength/diameterratiosofupto22havebeenetchedthroughtheSiO2film.TheresultsofcomputersimulationofthetrackformationprocessesinSiO2basedonthemodifiedthermalspikemodelarealsopresented.CalculatedradiusesofmoltenregionsalongswiftKriontrajectoriesinfusedsilicahavebeencomparedwithetchedtracksdimensions.Nanoclusterswereformedbyco−implantationofAsandInionsfollowedbyhigh−energyKrionsirradiationandthermalannealing.Thehigh−energyKrionsirradiationasathermalannealingalternativewascarriedouttoinducenanoclustersformationinswiftionstrackszones.TEMinvestigationsofannealedsamplesdemonstratethepresenceofamorphousnanoclusterslocatedatthedepthof40−190nm.Theirsizesvaryfrom10-15 nm and length/diameter ratios of up to 22 have been etched through the SiO 2 film. The results of computer simulation of the track formation processes in SiO 2 based on the modified thermal spike model are also presented. Calculated radiuses of molten regions along swift Kr ion trajectories in fused silica have been compared with etched tracks dimensions. Nanoclusters were formed by co-implantation of As and In ions followed by high-energy Kr ions irradiation and thermal annealing. The high-energy Kr ions irradiation as a thermal annealing alternative was carried out to induce nanoclusters formation in swift ions tracks zones. TEM investigations of annealed samples demonstrate the presence of amorphous nanoclusters located at the depth of 40-190 nm. Their sizes vary from 10−15nmandlength/diameterratiosofupto22havebeenetchedthroughtheSiO2film.TheresultsofcomputersimulationofthetrackformationprocessesinSiO2basedonthemodifiedthermalspikemodelarealsopresented.CalculatedradiusesofmoltenregionsalongswiftKriontrajectoriesinfusedsilicahavebeencomparedwithetchedtracksdimensions.Nanoclusterswereformedbyco−implantationofAsandInionsfollowedbyhigh−energyKrionsirradiationandthermalannealing.Thehigh−energyKrionsirradiationasathermalannealingalternativewascarriedouttoinducenanoclustersformationinswiftionstrackszones.TEMinvestigationsofannealedsamplesdemonstratethepresenceofamorphousnanoclusterslocatedatthedepthof40−190nm.Theirsizesvaryfrom2.5 to $6 nm. No influence of swift ion irradiation on the oriented precipitation of dopants (In+As) in the tracks region was revealed.

Research paper thumbnail of Structure and optical properties of silicon layers with GaSb nanocrystals created by ion-beam synthesis

physica status solidi (a), 2011

We have studied the ion-beam synthesis of GaSb nanocrystals in Si by high-fluence "hot" implantat... more We have studied the ion-beam synthesis of GaSb nanocrystals in Si by high-fluence "hot" implantation of Sb and Ga ions followed by thermal annealing. The Rutherford backscattering, transmission electron microscopy/ transmission electron diffraction, Raman spectroscopy and photoluminescence were used to characterize the implanted layers. It was found that the nanocrystal size increases from 5 to 60 nm in the samples annealed at 900 • C up to 20-90 nm in those annealed at 1100 • C. For the samples annealed at 900 • C a broad band in the region of 0.75-1.05 eV is registered in the photoluminescence spectra. The nature of this photoluminescence band is discussed.

Research paper thumbnail of Formation of InAs nanocrystals in Si by high-fluence ion implantation

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2008

We have studied the formation of InAs precipitates with dimensions of several nanometers in silic... more We have studied the formation of InAs precipitates with dimensions of several nanometers in silicon by means of As (245 keV, 5 Â 10 16 cm À2) and In (350 keV, 4.5 Â 10 16 cm À2) implantation at 500°C and subsequent annealing at 900°C for 45 min. RBS, SIMS, TEM/TED, RS and PL techniques were used to characterize the implanted layers. The surface density of the precipitates has been found to be about 1.2 Â 10 11 cm À2. Most of the crystallites are from 3 nm to 6 nm large. A band at 1.3 lm has been registered in the low-temperature PL spectra of (As + In) implanted and annealed silicon crystals. The PL band position follows the quantum confinement model for InAs.

Research paper thumbnail of Ion Beam Synthesis of InAs Nanocrystals in Si: Influence of Thin Surface Oxide Layers

Acta Physica Polonica A, 2013

Nanosized crystallites have been synthesized in the Si and SiO2/Si structures by means of As (170... more Nanosized crystallites have been synthesized in the Si and SiO2/Si structures by means of As (170 keV, 3.2 × 10 16 cm −2) and In (250 keV, 2.8 × 10 16 cm −2) implantation at 25 • C and 500 • C and subsequent annealing at 1050 • C for 3 min. The Rutherford backscattering, transmission electron microscopy, and photoluminescence techniques were used to analyse the impurity distribution as well as the structural and optical characteristics of the implanted layers. It was found that oxidation of samples before thermal treatment signicantly reduced the As and In losses. A broad band in the region of 1.21.5 µm was detected in the photoluminescence spectra. The highest photoluminescence yield for the samples after hot implantation and annealing was obtained. Anodic oxidation of the implanted samples before annealing results in the additional increase of photoluminescence yield.

Research paper thumbnail of Creation of Indium Arsenide Nanocrystallites in Silicon by Ion Implantation

Physics, Chemistry and Application of Nanostructures - Reviews and Short Notes - Proceedings of the International Conference on Nanomeeting-2007, 2007

ABSTRACT We have studied the synthesis of InAs nano-sized crystalline precipitates in crystalline... more ABSTRACT We have studied the synthesis of InAs nano-sized crystalline precipitates in crystalline silicon by means of the co-implantation of As(+) (245 keV, 5 x 10(16) cm(-2)) and In(+) (350 keV, 4.5 x 10(16) cm(-2)) at 500 degrees C and annealing at 900 degrees C for 45 min. RBS, TEM/TED and PL techniques were used to characterize the implanted layers. The density of the precipitates equals to 1.2 x 10(11) cm(-2). The most of the crystallites are from 2 nm to 8 nm in size. The precipitates are located within at the depths of 100 to 350 nm. A broad line at 1.3 mu m is found in low-temperature PL spectra of co-implanted and annealed silicon crystals This line can be attributed to donor-acceptor pair recombination between In and As atoms which occupy the substitutional sites in the silicon lattice.

Research paper thumbnail of Radiative recombination in zinc blende ZnSe nanocrystals ion-beam synthesized in silica

Journal of Physics D: Applied Physics, 2022

Zinc selenide nanocrystals (NCs) were successfully synthesized in silicon dioxide (silica grown o... more Zinc selenide nanocrystals (NCs) were successfully synthesized in silicon dioxide (silica grown on a silicon wafer) by high-fluence implantation of Zn+ and Se+ ions with subsequent rapid thermal annealing at 1000°C for 3 min. The high crystalline quality of the zinc blende ZnSe nanoclusters was proven by transmission electron microscopy with selected area electron diffraction and Raman spectroscopy. Low-temperature photoluminescence (PL) reveals the recombination of excitons in ZnSe, what further indicates a good crystalline quality of the synthesized nanocrystals. PL analysis shows a strong coupling of phonons and excitons. The Huang−Rhys parameter of the longitudinal optical phonon in the exciton transition S is in the range of 0.6−0.7. Despite the excellent quality of the ZnSe NCs synthesized in silica, defect states inside the NCs or at the NCs/SiO2 interface with activation energies of 0.1–0.2, 0.45 and 0.67 eV play a crucial role in radiative recombination.

Research paper thumbnail of Luminescence of ZnO nanocrystals in silica synthesized by dual (Zn, O) implantation and thermal annealing

Journal of Physics D: Applied Physics, 2021

Zinc blende ZnO nanocrystals (NCs) were synthesised in amorphous silica by high-fluence dual (Zn,... more Zinc blende ZnO nanocrystals (NCs) were synthesised in amorphous silica by high-fluence dual (Zn, O) ion implantation and subsequent thermal annealing in air. We observed the formation of core/shell nanoparticles at the depth of maximum Zn concentration as a result of an incomplete oxidation process. The silica matrix with ZnO NCs exhibits an intense white-greenish emission. Low-temperature photoluminescence spectroscopy revealed various radiative recombination mechanisms in the zinc blende ZnO NCs involving intrinsic defects that act as donors and acceptors.

Research paper thumbnail of Shi Irradiation of A IIIB v Nanoparticles and (Zn)Core /(ZnO)Shell Nanostructures Ion-Beam Synthesized in Silica: Shape Elongation, Enhanced Sputtering and Photoluminescence

SSRN Electronic Journal, 2021

Till now, shape elongation phenomenon was observed predominantly for metal nanoparticles irradiat... more Till now, shape elongation phenomenon was observed predominantly for metal nanoparticles irradiated with swift heavy ions (SHI). For the first time, we report the shape elongation of InAs and Zn(core)/ZnO(shell) nanoparticles (NPs) embedded in a silica matrix and irradiated with swift Xe ions. In case of InAs NPs, SHI irradiation results in the formation of nanorods. A diversity of elongated features is observed for Zn-based NPs: chains of small ZnO clusters, elongated (Zn)core/(ZnO)shell structures and drop-like elongated Zn particles. The intense sputtering of the silicon dioxide layer due to electronic excitations has revealed for “SiO2+Zn-based NPs” composite. Photoluminescence (PL) spectroscopy reveals emission in the visible range for two types of nanocomposites before SHIs irradiation. This emission is attributed to the oxygen excess-related defect (NBOHC) as well as to the oxygen deficiency-related centres created in silica matrix during the implantation of cluster-forming ions (In + As or Zn). The intensive band in the spectral region of 2.8 – 3.1 eV is observed in PL spectrum of annealed “SiO2+InAs NPs” composite. SHI irradiation results in its quenching and formation of an asymmetrical band centred at 1.9 eV. In case of “SiO2+Zn-based NPs” composite, SHIs irradiation results in substantial increase of PL in orange spectral range. The origin of observed emission is discussed.

Research paper thumbnail of Formation of Platinum Silicide During the Rapid Thermal Processing of the System Platinum-Silicon: Microstructure and Electrophysical Characteristics

High Temperature Material Processes: An International Quarterly of High-Technology Plasma Processes, 2019

Research paper thumbnail of Reprint of “Structure and optical properties of SiO2 films with ZnSe nanocrystals formed by ion implantation”

Surface and Coatings Technology, 2019

ZnSe nanocrystals have been formed in the silicon dioxide matrix by the sequential high-fluence i... more ZnSe nanocrystals have been formed in the silicon dioxide matrix by the sequential high-fluence implantation of Zn + and Se + ions at 500°C. After implantation a part of samples was annealed at 1000°C for 3 min using rapid thermal annealing. Structural and optical properties of ZnSe/SiO 2 nano-composite films were analyzed by means of Rutherford Backscattering Spectrometry, cross-sectional Transmission Electron Microscopy, Raman scattering and photoluminescence techniques. It was shown that a sequence of implantation affects structural and optical properties of synthesized ZnSe clusters. Based on the Raman scattering and photoluminescence data the samples for which Zn ions were implanted first exhibited a better ZnSe crystalline quality than those of reverse sequence of implantation, i.e. with Se ions implanted at the beginning. The bands of blue ZnSe band edge emission and green-red ZnSe deep defect level emission were revealed in the PL spectra of the as-implanted and annealed nano-composites. The PL spectral features observed in the blue region are due to the quantum-size effects in the ZnSe nanocrystals embedded into the silicon dioxide matrix. The PL intensity ratio of the deep defect band to the near edge emission is higher in the samples first implanted with Se ions, and Zn ions implanted next. The effect of rapid thermal annealing on structural and light-emitting properties was discussed.

Research paper thumbnail of Formation of Platinum Silicide Layers During the Rapid Thermal Processing of the System Platinum-Silicon: Structural-Phase Changes

High Temperature Material Processes: An International Quarterly of High-Technology Plasma Processes, 2019

Research paper thumbnail of Optical properties of silicon nitride films formed by plasma-chemical vapor deposition

Journal of Applied Spectroscopy, 2013

The optical properties and structure of layers of silicon nitride deposited on silicon substrates... more The optical properties and structure of layers of silicon nitride deposited on silicon substrates by plasma-aided chemical vapor deposition at 300°C are studied by ellipsometry, Raman scattering, IR spectroscopy, and photoluminescence techniques. It is found that immediately after deposition the silicon nitride contains hydrogen in the form of Si-H bonds. Annealing (1100°C, 30 min) leads to dehydrogenation and densifi cation of the nitride layer. An intense Si 3 N 4 photoluminescence signal is detected in the green. Immediately after deposition the photoluminescence peak appears at 542 nm and annealing shifts it to shorter wavelengths.

Research paper thumbnail of Structural and optical properties of silicon layers with InSb and InAs nanocrystals formed by ion-beam synthesis

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2013

We have studied the formation of InSb and InAs precipitates with sizes of several nanometers in S... more We have studied the formation of InSb and InAs precipitates with sizes of several nanometers in Si and SiO 2 /Si by means of implantation of (Sb + In) or (As + In) ions with energies from 170 to 350 keV and fluencies from 2.8 to 3.5 Â 10 16 cm À2 at 500°C and subsequent annealing at 1050-1100°C for 3-30 min. RBS, TEM/TED, RS and PL techniques were employed to characterize the implanted layers. A broad band in the region of 1.2-1.6 lm has been registered in the low-temperature PL spectra of both (Sb + In) and (As + In) implanted and annealed silicon crystals. It was shown that structural and optical properties of oxidized silicon crystals strongly depend on type of implanted species in silicon crystals.

Research paper thumbnail of Structural and Luminescent Properties of Sn-Doped SiO2 Layers

Journal of Applied Spectroscopy, 2014

ABSTRACT The formation of tin nanocrystallites in a SiO2:Sn matrix using a high-dose implantation... more ABSTRACT The formation of tin nanocrystallites in a SiO2:Sn matrix using a high-dose implantation technique followed by high-temperature processing was studied. Structural phase transformations were studied by plan-view transmission electron microscopy. Optical properties of the implanted samples were investigated by photoluminescence. It was shown that annealing of the implanted SiO2 layers formed nanoprecipitates of β-Sn and caused the appearance of regions enriched in SnO2. Photoluminescence spectra of implanted and annealed samples exhibited intense emission in photon energy range 1.3-3.6 eV that was attributed to oxygen-deficit centers created in the SiO2:Sn matrix and at the nanocluster/SiO2 interface.

Research paper thumbnail of Light Emitting Single-Crystalline Silicon Wafers Implanted with V and III Group Ions

Acta Physica Polonica A, 2014

Compound semiconductor nanocrystals (InAs, InSb, GaSb) were successfully synthesized in single cr... more Compound semiconductor nanocrystals (InAs, InSb, GaSb) were successfully synthesized in single crystalline Si by high uence ion implantation at 500 • C followed by high-temperature rapid thermal annealing or conventional furnace annealing at 9001100 • C. Rutherford backscattering spectrometry, transmission electron microscopy/ transmission electron diraction, Raman scattering, and photoluminescence were employed to characterize the implanted layers. Two dierent types of the broad band emission extending over 0.751.1 eV were observed in photoluminescence spectra of annealed samples. One of the bands disappears in photoluminescence spectra of samples annealed at 1100 • C unlike the other one.

Research paper thumbnail of Identification of nickel silicide phases on a silicon surface from Raman spectra

Journal of Applied Spectroscopy, 2013

We have demonstrated the effectiveness of Raman spectroscopy for monitoring nickel silicide forma... more We have demonstrated the effectiveness of Raman spectroscopy for monitoring nickel silicide formation processes on the surface of silicon wafers, with deposition of a composite metal layer (nickel, platinum, and vanadium) under industrial process conditions in microelectronics. The observed shift of all the NiSi lines toward lower energies is associated with formation of the metastable silicide phase Ni 1-x Pt x Si, which leads to the presence of stresses in the lattice as a result of the increase in the distances between atoms.

Research paper thumbnail of Raman study of light-emitting SiNx films grown on Si by low-pressure chemical vapor deposition

Thin Solid Films, 2015

Si-rich silicon nitride (SRSN) films were deposited on Si wafers by low pressure chemical vapor d... more Si-rich silicon nitride (SRSN) films were deposited on Si wafers by low pressure chemical vapor deposition (LPCVD) technique and, subsequently, annealed at (800-1200) °C to form Si precipitates. The composition of SiN x films was measured by Rutherford backscattering spectrometry (RBS). Two sets of samples differed by the amount of excessive Si (Si exc) in silicon nitride were studied. Evolution of Si nanoclusters from amorphous to crystalline ones during high temperature treatment was examined by Raman scattering (RS) spectroscopy. The amorphous Si clusters were already revealed in as-deposited SiN x while the annealing results in their crystallization. The crystalline nanoprecipitates are only registered in nitride films after annealing at 1200 °C. A dependence of Raman scattering intensity from the Si wafer on the temperature of annealing of SiN x /Si structures was revealed. This information was used to explain the phase transformations in SRSNs during high temperature treatments. The peculiarities of photoluminescence (PL) spectra for two sets of Si-rich SiN x films are explained

Research paper thumbnail of Effects of Annealing Regims on the Structural and Optical Properties of Inas and Gasb Nanocryctals Created by Ion–Beam Synthesis in Si Matrix

We have studied the ion-beam synthesis of InAs and GaSb nanocrystals in Si by high-fluence implan... more We have studied the ion-beam synthesis of InAs and GaSb nanocrystals in Si by high-fluence implantation of (As+In) and (Ga+Sb) ions followed a thermal annealing. In order to characterize the implanted samples Rutherford backscattering spectrometry in combination with the channelling (RBS/C), transmission electron microscopy (TEM), Raman spectrometry (RS) and low-temperature photoluminescence (PL) techniques were employed. It was demonstrated that by introducing getter, varying the ion implantation temperature, ion fluences and post-implantation annealing duration and temperature it is possible to form InAs and GaSb nanocrystals in the range of sizes of (2 – 80) nm and create different types of secondary defects distribution. RS results confirm the crystalline state of the clusters in the silicon matrix after high-fluence implantation of heavy (As+In) and (Ga+Sb) ions. Significant redistribution of implanted species has been revealed after "hot" implantation and post-implan...

Research paper thumbnail of Effect of implantation and annealing regimes on ion-beam synthesis of InAs nanocrystals

Lithuanian Journal of Physics, 2009

We reported the formation of nanosized InAs crystallites in silicon wafers by means of As (245 ke... more We reported the formation of nanosized InAs crystallites in silicon wafers by means of As (245 keV, 4.1•10 16 cm −2) and In (350 keV, 3.7•10 16 cm −2) implantation. The implantation was carried out at 25 and 500 • C. In order to verify the effect of getter on precipitates growth an additional procedure was carried out for the samples implanted with As and In species at the room temperature. This procedure included the implantation of H + 2 ions with the energy of 100 keV at 1.2•10 16 cm −2. Afterwards, the samples were annealed at 900 • C for 60 min in inert ambient. In order to characterize the implanted layers, Rutherford backscattering spectrometry in combination with the channelling (RBS / C) and transmission electron microscopy (TEM) techniques were used. TEM has revealed InAs nanocrystals in implanted samples after the annealing. It has been shown that average size and size distribution of InAs clusters depend on implantation temperature and annealing duration. Significant diffusional redistribution of implanted species has been revealed after "hot" implantation and post-implantation annealing. We have suggested that it is caused by non-equilibrium diffusion. The radiation-enhanced diffusivities at "hot" implantation have been determined for the abovementioned experimental conditions.

Research paper thumbnail of Ion-Beam Synthesis of InSb Nanocrystals in Si Matrix

Advanced Materials Research, 2013

The results of structural and optical investigation of crystalline Si with embedded InSb nanocrys... more The results of structural and optical investigation of crystalline Si with embedded InSb nanocrystals are reported. These nanocrystals were synthesized in silicon matrix by means of high-fluence “hot” implantation of Sb and In ions followed by thermal treatment. TEM gives an evidence of nanocrystal formation in implanted and annealed samples as well as an existence of microtwins and dislocation-type defects and substantial residual mechanical strains. We have identified nanocrystals as InSb from RS data. Mechanical strains in “silicon – InSb nanocrystals” system have been evaluated, too.

Research paper thumbnail of Ion-beam formation of nanopores and nanoclusters in SiO2

Vacuum, 2005

We studied nanopores and nanoclusters formation in thermally oxidized silicon wafers (SiO 2 /Si) ... more We studied nanopores and nanoclusters formation in thermally oxidized silicon wafers (SiO 2 /Si) by means of ionbeam technique. RBS, SEM, TEM and TED were used to characterize the SiO 2 layers after the ion-beam processing. Nanopores were formed by high-energy Kr ions irradiation followed by chemical etching of latent tracks zones in SiO 2 matrix. Holes with diameters of 10−15nmandlength/diameterratiosofupto22havebeenetchedthroughtheSiO2film.TheresultsofcomputersimulationofthetrackformationprocessesinSiO2basedonthemodifiedthermalspikemodelarealsopresented.CalculatedradiusesofmoltenregionsalongswiftKriontrajectoriesinfusedsilicahavebeencomparedwithetchedtracksdimensions.Nanoclusterswereformedbyco−implantationofAsandInionsfollowedbyhigh−energyKrionsirradiationandthermalannealing.Thehigh−energyKrionsirradiationasathermalannealingalternativewascarriedouttoinducenanoclustersformationinswiftionstrackszones.TEMinvestigationsofannealedsamplesdemonstratethepresenceofamorphousnanoclusterslocatedatthedepthof40−190nm.Theirsizesvaryfrom10-15 nm and length/diameter ratios of up to 22 have been etched through the SiO 2 film. The results of computer simulation of the track formation processes in SiO 2 based on the modified thermal spike model are also presented. Calculated radiuses of molten regions along swift Kr ion trajectories in fused silica have been compared with etched tracks dimensions. Nanoclusters were formed by co-implantation of As and In ions followed by high-energy Kr ions irradiation and thermal annealing. The high-energy Kr ions irradiation as a thermal annealing alternative was carried out to induce nanoclusters formation in swift ions tracks zones. TEM investigations of annealed samples demonstrate the presence of amorphous nanoclusters located at the depth of 40-190 nm. Their sizes vary from 10−15nmandlength/diameterratiosofupto22havebeenetchedthroughtheSiO2film.TheresultsofcomputersimulationofthetrackformationprocessesinSiO2basedonthemodifiedthermalspikemodelarealsopresented.CalculatedradiusesofmoltenregionsalongswiftKriontrajectoriesinfusedsilicahavebeencomparedwithetchedtracksdimensions.Nanoclusterswereformedbyco−implantationofAsandInionsfollowedbyhigh−energyKrionsirradiationandthermalannealing.Thehigh−energyKrionsirradiationasathermalannealingalternativewascarriedouttoinducenanoclustersformationinswiftionstrackszones.TEMinvestigationsofannealedsamplesdemonstratethepresenceofamorphousnanoclusterslocatedatthedepthof40−190nm.Theirsizesvaryfrom2.5 to $6 nm. No influence of swift ion irradiation on the oriented precipitation of dopants (In+As) in the tracks region was revealed.

Research paper thumbnail of Structure and optical properties of silicon layers with GaSb nanocrystals created by ion-beam synthesis

physica status solidi (a), 2011

We have studied the ion-beam synthesis of GaSb nanocrystals in Si by high-fluence "hot" implantat... more We have studied the ion-beam synthesis of GaSb nanocrystals in Si by high-fluence "hot" implantation of Sb and Ga ions followed by thermal annealing. The Rutherford backscattering, transmission electron microscopy/ transmission electron diffraction, Raman spectroscopy and photoluminescence were used to characterize the implanted layers. It was found that the nanocrystal size increases from 5 to 60 nm in the samples annealed at 900 • C up to 20-90 nm in those annealed at 1100 • C. For the samples annealed at 900 • C a broad band in the region of 0.75-1.05 eV is registered in the photoluminescence spectra. The nature of this photoluminescence band is discussed.

Research paper thumbnail of Formation of InAs nanocrystals in Si by high-fluence ion implantation

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2008

We have studied the formation of InAs precipitates with dimensions of several nanometers in silic... more We have studied the formation of InAs precipitates with dimensions of several nanometers in silicon by means of As (245 keV, 5 Â 10 16 cm À2) and In (350 keV, 4.5 Â 10 16 cm À2) implantation at 500°C and subsequent annealing at 900°C for 45 min. RBS, SIMS, TEM/TED, RS and PL techniques were used to characterize the implanted layers. The surface density of the precipitates has been found to be about 1.2 Â 10 11 cm À2. Most of the crystallites are from 3 nm to 6 nm large. A band at 1.3 lm has been registered in the low-temperature PL spectra of (As + In) implanted and annealed silicon crystals. The PL band position follows the quantum confinement model for InAs.

Research paper thumbnail of Ion Beam Synthesis of InAs Nanocrystals in Si: Influence of Thin Surface Oxide Layers

Acta Physica Polonica A, 2013

Nanosized crystallites have been synthesized in the Si and SiO2/Si structures by means of As (170... more Nanosized crystallites have been synthesized in the Si and SiO2/Si structures by means of As (170 keV, 3.2 × 10 16 cm −2) and In (250 keV, 2.8 × 10 16 cm −2) implantation at 25 • C and 500 • C and subsequent annealing at 1050 • C for 3 min. The Rutherford backscattering, transmission electron microscopy, and photoluminescence techniques were used to analyse the impurity distribution as well as the structural and optical characteristics of the implanted layers. It was found that oxidation of samples before thermal treatment signicantly reduced the As and In losses. A broad band in the region of 1.21.5 µm was detected in the photoluminescence spectra. The highest photoluminescence yield for the samples after hot implantation and annealing was obtained. Anodic oxidation of the implanted samples before annealing results in the additional increase of photoluminescence yield.

Research paper thumbnail of Creation of Indium Arsenide Nanocrystallites in Silicon by Ion Implantation

Physics, Chemistry and Application of Nanostructures - Reviews and Short Notes - Proceedings of the International Conference on Nanomeeting-2007, 2007

ABSTRACT We have studied the synthesis of InAs nano-sized crystalline precipitates in crystalline... more ABSTRACT We have studied the synthesis of InAs nano-sized crystalline precipitates in crystalline silicon by means of the co-implantation of As(+) (245 keV, 5 x 10(16) cm(-2)) and In(+) (350 keV, 4.5 x 10(16) cm(-2)) at 500 degrees C and annealing at 900 degrees C for 45 min. RBS, TEM/TED and PL techniques were used to characterize the implanted layers. The density of the precipitates equals to 1.2 x 10(11) cm(-2). The most of the crystallites are from 2 nm to 8 nm in size. The precipitates are located within at the depths of 100 to 350 nm. A broad line at 1.3 mu m is found in low-temperature PL spectra of co-implanted and annealed silicon crystals This line can be attributed to donor-acceptor pair recombination between In and As atoms which occupy the substitutional sites in the silicon lattice.