2021 IEEE 16th International Conference on the Experience of Designing and Application of CAD Systems (CADSM), 2021
The effect of proton flux on surface plasmon resonance (SPR) sensors has been studied. The SPR se... more The effect of proton flux on surface plasmon resonance (SPR) sensors has been studied. The SPR sensor is a 50 nm thick gold film. A stream of protons was directed to the surface of the SPR sensor by electrolysis. It was studied the effects of flows with a density of: 3.47*10<sup>12</sup> 1/(cm<sup>2</sup>*s); 3.82*10<sup>12</sup> 1/(cm<sup>2</sup>*s); 8.68*10<sup>12</sup> 1/(cm2*s). The number of protons that reached 1 cm<sup>2</sup>of the gold film surface during electrolysis was, respectively: 1.25*10<sup>16</sup>1/cm<sup>2</sup>; 0.69*10<sup>15</sup> 1/cm<sup>2</sup>; 1.56*10<sup>15</sup> 1/cm<sup>2</sup>. Such actions of protons changed the dielectric properties of the gold film. The SPR curves maximum shifted to larger angles.
The present paper deals with the experimental and theoretical studies of changes of optical prope... more The present paper deals with the experimental and theoretical studies of changes of optical properties of SPR sensors under the influence of hydrogen. Theoretical modeling of the SPR sensor treated with hydrogen was performed using the transfer matrix method and effective medium approaches. Different possibilities of hydrogen influence were considered during the modeling. It was established that the accumulation of hydrogen at the glass-chromium interface could not change the SPR spectrum. The experimentally observed shifts in the SPR spectrum were mainly related to the accumulation of hydrogen in all thicknesses of the gold layer by means of the formation of cavities filled with hydrogen. The accumulation of hydrogen in the bulk of the gold film also led to an increase in the SPR resonance value. On the contrary, the theoretical modeling of the increase in the surface roughness of gold predicted a decrease in the amplitude of the resonance. As a result, a complex theoretical description of the processes, which took place in SPR sensors during hydrogen treatment, was proposed. The predictions were as follows. The oscillations of the surface level before hydrogen treatment were 2 nm, and due to the possibility of surface destruction, the oscillations of the surface level increased to 3 nm. The layer of "solid" gold before hydrogen treatment was 48.5 nm, and after hydrogen it increased to 53.35 nm. The average volume concentration of cavities in this layer was about 10 %. The cavities with hydrogen were homogeneously distributed over the volume. The thickness of the chromium layer before hydrogen treatment was 5 nm, and after hydrogen treatment the thickness of this layer increased to 6 nm. The volume of cavities with hydrogen in chromium was 20 %.
The effect of hydrogen on a surface plasmon resonance sensor was studied. The sensor is a glass p... more The effect of hydrogen on a surface plasmon resonance sensor was studied. The sensor is a glass plate of 1 mm thickness with a gold film applied to one surface. To increase the adhesion of the gold film on the glass a thin chromium interlayer between the gold film and the glass plate was applied. Thickness of the chromium layer was 5 nm. The thickness of the gold film was 50 nm. Hydrogen treatment was performed by means of electrolysis in a 10 % water solution of sulfuric acid (H2SO4). The surface of the gold film served as the cathode. Electrolysis lasted for 6 min. At room temperature due to electrolysis, the gold film was saturated with water. During the hydrogen treatment of the sensor, constant electric currents were maintained. A series of samples were treated with different electrolysis currents (50-2 A). The influence of the proton flux density to the surface of the gold film on the properties of the surface plasmon resonance sensor was studied. For this purpose, the proton flux density during hydrogen treatment was changed from 8.8610 13 to 3.4710 12 1/(cm 2 s). Optical properties of treated and untreated sensors were studied experimentally by means of Plasmon-5 spectrometer. Hydrogen treatment changed the optical properties of the surface plasmon resonance sensor over time after hydrogen treatment. The biggest changes occurred during the first days, which gradually slowed down. It was established that after hydrogen treatment the surface plasmon resonance curve was shifted in the direction of larger angles in comparison with the case of an untreated sensor. It was also found that treatment with large fluxes of protons is less effective in changing the optical properties of the sensor than with smaller ones.
Plate of p-silicon of 0.35 mm thickness was the sample of present studies. Two gold film contacts... more Plate of p-silicon of 0.35 mm thickness was the sample of present studies. Two gold film contacts of 50 nm thickness were deposited on the opposite surfaces of p-silicon sample. For the manufacturing of gold film contacts the method of direct contact heating in a tungsten boat was used. The surface of the silicon plate was activated before the deposition of gold by dipping the samples into a 0.5 % solution of hydrofluoric acid. The silicon wafer was then washed with distilled water, dried and placed in a container for substrates. After deposition of the gold film contact, the plate of p-silicon was cut in several samples. The hydrogen treatment of only one gold film contact was executed by means of electrolysis in 10 % water solution of H2SO4. The gold contact was the cathode and the graphite electrode was the anode. The second gold film contact was isolated during the electrolysis. The electrolysis lasted for 6 min. The current density during electrolysis was 117.5 A/m 2. The p-silicon samples with gold contacts processed by hydrogen were stored at room conditions. The time dependence of the volt-ampere characteristics of the samples was investigated. The resistance of the gold film contact increased in the first few hours after hydrogen processing. But then, during the week after hydrogen treatment, the resistance of the gold film contact constantly diminished. During the next week, the resistance of the gold film contact did not change. The hydrogen saturation of the gold film contact caused the significant reduction of the resistance of the gold contact. After treatment and exposure at room conditions, the final resistance of the gold film contact decreased by almost 1.5 times in comparison with the contact resistance before hydrogen treatment.
The present work demonstrates that hydrogen treatment is capable to destroy and to split the surf... more The present work demonstrates that hydrogen treatment is capable to destroy and to split the surface of silicon single crystal. Hydrogen treatment is performed after the proton irradiation of the silicon surface. All operations with the silicon single crystal are performed at room temperature. The surface of the crystal is irradiated with a proton beam. The proton energy in the beam is 1.5 MeV. The energy spread did not exceed 150 eV. The integral radiation fluence is 2⋅10 14 p/cm 2. Such a dose of radiation is sufficient to form a thin layer with a high density of radiation defects at a depth of 30 µm under the surface. The existence of this thin layer is confirmed after chemical manifestation by observations on the electron microscope. After irradiation, an electrolytic saturation of the silicon sample with hydrogen is carried out through
2020 IEEE 10th International Conference Nanomaterials: Applications & Properties (NAP)
The influence of hydrogen treatment of a 50 nm thick gold film deposited on a glass on properties... more The influence of hydrogen treatment of a 50 nm thick gold film deposited on a glass on properties of the film is studied. It was established that proton fluxes with a density higher than $8.68\square 10^{14} 1/(\mathrm{c}\mathrm{m}^{2}\square \mathrm{s})$ destroyed the film and changed it plasmonic properties. It was also found that the flow of protons to the surface of the gold film with a much smaller density of $8.68\square 10^{12}1/(\mathrm{c}\mathrm{m}^{2}\square \mathrm{s})$ significantly changes the optical properties. The resonance curve of the plasmon resonance shifts towards larger angles by 1.33° after hydrogen treatment. The amplitude of the resonant curve of the SPR does not change.
2019 IEEE 39th International Conference on Electronics and Nanotechnology (ELNANO), 2019
The sample for the experimental studies was the layered metal-semiconductor formation. There have... more The sample for the experimental studies was the layered metal-semiconductor formation. There have been the two films of gold of 50 nm thicknesses deposited unto opposite surfaces of p-silicon with a surface layer of silicon oxide. The effect of 1.5 MeV proton beam on sample was investigated. Only the uncovered by films surface of the sample was irradiated. The integral dose of irradiation was 2*1015 p / cm2. The direction of the proton beam was parallel to the contacts. Performed with the irradiated sample experiments detected changes of the electrical properties of the gold film contacts far away from the active region of irradiation. After irradiation the contact resistance decreased by several times.
The problem of light trapping engineering for semiconductor surfaces covered with randomly distri... more The problem of light trapping engineering for semiconductor surfaces covered with randomly distributed spheroidal metallic nanoparticles has been considered. The absorption of incident light by such a structure has been calculated using the Green functions method, involving the concept of an effective susceptibility. A target function, optimizing broad-band light absorption throughout the visible range has been constructed taking the geometry of the structure as the control parameters. The optimization problem of light-trapping in such structure has been solved, and the optimum nanoparticle coverage for matching the required shape of absorption spectra has been obtained. Our results can be applied to the design of plasmonic-enhanced light-collecting elements in solar cells.
2021 IEEE 16th International Conference on the Experience of Designing and Application of CAD Systems (CADSM), 2021
Present studies is devoted to optimization problem of the morphology of thin layered nanocomposit... more Present studies is devoted to optimization problem of the morphology of thin layered nanocomposite Teflon films. By the use of the information about the shape of nanoparticles and their concentration near configurational resonances for single layer film the model of multilayered Teflon films, which well absorb in the visible range of external light, was proposed. Results of theoretical studies of present paper can be linked with further experiments and can be useful to suggest possible guided instructions to provide experimental investigations.
2019 IEEE 39th International Conference on Electronics and Nanotechnology (ELNANO), 2019
The problem of optimization of morphology of nanocomposite thin films with spheroid metallic nano... more The problem of optimization of morphology of nanocomposite thin films with spheroid metallic nanoinclusions was considered. The function of quadratic deviation from willing spectrum of absorption was used as target function. To optimize morphology of nanocomposite films, the pattern search was applied. The optimal morphologies of nanocomposite thin films were obtained. Theoretically optimized nanocomposite thin films effectively transmitted external light in all visible range
2021 IEEE 16th International Conference on the Experience of Designing and Application of CAD Systems (CADSM), 2021
The effect of proton flux on surface plasmon resonance (SPR) sensors has been studied. The SPR se... more The effect of proton flux on surface plasmon resonance (SPR) sensors has been studied. The SPR sensor is a 50 nm thick gold film. A stream of protons was directed to the surface of the SPR sensor by electrolysis. It was studied the effects of flows with a density of: 3.47*10<sup>12</sup> 1/(cm<sup>2</sup>*s); 3.82*10<sup>12</sup> 1/(cm<sup>2</sup>*s); 8.68*10<sup>12</sup> 1/(cm2*s). The number of protons that reached 1 cm<sup>2</sup>of the gold film surface during electrolysis was, respectively: 1.25*10<sup>16</sup>1/cm<sup>2</sup>; 0.69*10<sup>15</sup> 1/cm<sup>2</sup>; 1.56*10<sup>15</sup> 1/cm<sup>2</sup>. Such actions of protons changed the dielectric properties of the gold film. The SPR curves maximum shifted to larger angles.
The present paper deals with the experimental and theoretical studies of changes of optical prope... more The present paper deals with the experimental and theoretical studies of changes of optical properties of SPR sensors under the influence of hydrogen. Theoretical modeling of the SPR sensor treated with hydrogen was performed using the transfer matrix method and effective medium approaches. Different possibilities of hydrogen influence were considered during the modeling. It was established that the accumulation of hydrogen at the glass-chromium interface could not change the SPR spectrum. The experimentally observed shifts in the SPR spectrum were mainly related to the accumulation of hydrogen in all thicknesses of the gold layer by means of the formation of cavities filled with hydrogen. The accumulation of hydrogen in the bulk of the gold film also led to an increase in the SPR resonance value. On the contrary, the theoretical modeling of the increase in the surface roughness of gold predicted a decrease in the amplitude of the resonance. As a result, a complex theoretical description of the processes, which took place in SPR sensors during hydrogen treatment, was proposed. The predictions were as follows. The oscillations of the surface level before hydrogen treatment were 2 nm, and due to the possibility of surface destruction, the oscillations of the surface level increased to 3 nm. The layer of "solid" gold before hydrogen treatment was 48.5 nm, and after hydrogen it increased to 53.35 nm. The average volume concentration of cavities in this layer was about 10 %. The cavities with hydrogen were homogeneously distributed over the volume. The thickness of the chromium layer before hydrogen treatment was 5 nm, and after hydrogen treatment the thickness of this layer increased to 6 nm. The volume of cavities with hydrogen in chromium was 20 %.
The effect of hydrogen on a surface plasmon resonance sensor was studied. The sensor is a glass p... more The effect of hydrogen on a surface plasmon resonance sensor was studied. The sensor is a glass plate of 1 mm thickness with a gold film applied to one surface. To increase the adhesion of the gold film on the glass a thin chromium interlayer between the gold film and the glass plate was applied. Thickness of the chromium layer was 5 nm. The thickness of the gold film was 50 nm. Hydrogen treatment was performed by means of electrolysis in a 10 % water solution of sulfuric acid (H2SO4). The surface of the gold film served as the cathode. Electrolysis lasted for 6 min. At room temperature due to electrolysis, the gold film was saturated with water. During the hydrogen treatment of the sensor, constant electric currents were maintained. A series of samples were treated with different electrolysis currents (50-2 A). The influence of the proton flux density to the surface of the gold film on the properties of the surface plasmon resonance sensor was studied. For this purpose, the proton flux density during hydrogen treatment was changed from 8.8610 13 to 3.4710 12 1/(cm 2 s). Optical properties of treated and untreated sensors were studied experimentally by means of Plasmon-5 spectrometer. Hydrogen treatment changed the optical properties of the surface plasmon resonance sensor over time after hydrogen treatment. The biggest changes occurred during the first days, which gradually slowed down. It was established that after hydrogen treatment the surface plasmon resonance curve was shifted in the direction of larger angles in comparison with the case of an untreated sensor. It was also found that treatment with large fluxes of protons is less effective in changing the optical properties of the sensor than with smaller ones.
Plate of p-silicon of 0.35 mm thickness was the sample of present studies. Two gold film contacts... more Plate of p-silicon of 0.35 mm thickness was the sample of present studies. Two gold film contacts of 50 nm thickness were deposited on the opposite surfaces of p-silicon sample. For the manufacturing of gold film contacts the method of direct contact heating in a tungsten boat was used. The surface of the silicon plate was activated before the deposition of gold by dipping the samples into a 0.5 % solution of hydrofluoric acid. The silicon wafer was then washed with distilled water, dried and placed in a container for substrates. After deposition of the gold film contact, the plate of p-silicon was cut in several samples. The hydrogen treatment of only one gold film contact was executed by means of electrolysis in 10 % water solution of H2SO4. The gold contact was the cathode and the graphite electrode was the anode. The second gold film contact was isolated during the electrolysis. The electrolysis lasted for 6 min. The current density during electrolysis was 117.5 A/m 2. The p-silicon samples with gold contacts processed by hydrogen were stored at room conditions. The time dependence of the volt-ampere characteristics of the samples was investigated. The resistance of the gold film contact increased in the first few hours after hydrogen processing. But then, during the week after hydrogen treatment, the resistance of the gold film contact constantly diminished. During the next week, the resistance of the gold film contact did not change. The hydrogen saturation of the gold film contact caused the significant reduction of the resistance of the gold contact. After treatment and exposure at room conditions, the final resistance of the gold film contact decreased by almost 1.5 times in comparison with the contact resistance before hydrogen treatment.
The present work demonstrates that hydrogen treatment is capable to destroy and to split the surf... more The present work demonstrates that hydrogen treatment is capable to destroy and to split the surface of silicon single crystal. Hydrogen treatment is performed after the proton irradiation of the silicon surface. All operations with the silicon single crystal are performed at room temperature. The surface of the crystal is irradiated with a proton beam. The proton energy in the beam is 1.5 MeV. The energy spread did not exceed 150 eV. The integral radiation fluence is 2⋅10 14 p/cm 2. Such a dose of radiation is sufficient to form a thin layer with a high density of radiation defects at a depth of 30 µm under the surface. The existence of this thin layer is confirmed after chemical manifestation by observations on the electron microscope. After irradiation, an electrolytic saturation of the silicon sample with hydrogen is carried out through
2020 IEEE 10th International Conference Nanomaterials: Applications & Properties (NAP)
The influence of hydrogen treatment of a 50 nm thick gold film deposited on a glass on properties... more The influence of hydrogen treatment of a 50 nm thick gold film deposited on a glass on properties of the film is studied. It was established that proton fluxes with a density higher than $8.68\square 10^{14} 1/(\mathrm{c}\mathrm{m}^{2}\square \mathrm{s})$ destroyed the film and changed it plasmonic properties. It was also found that the flow of protons to the surface of the gold film with a much smaller density of $8.68\square 10^{12}1/(\mathrm{c}\mathrm{m}^{2}\square \mathrm{s})$ significantly changes the optical properties. The resonance curve of the plasmon resonance shifts towards larger angles by 1.33° after hydrogen treatment. The amplitude of the resonant curve of the SPR does not change.
2019 IEEE 39th International Conference on Electronics and Nanotechnology (ELNANO), 2019
The sample for the experimental studies was the layered metal-semiconductor formation. There have... more The sample for the experimental studies was the layered metal-semiconductor formation. There have been the two films of gold of 50 nm thicknesses deposited unto opposite surfaces of p-silicon with a surface layer of silicon oxide. The effect of 1.5 MeV proton beam on sample was investigated. Only the uncovered by films surface of the sample was irradiated. The integral dose of irradiation was 2*1015 p / cm2. The direction of the proton beam was parallel to the contacts. Performed with the irradiated sample experiments detected changes of the electrical properties of the gold film contacts far away from the active region of irradiation. After irradiation the contact resistance decreased by several times.
The problem of light trapping engineering for semiconductor surfaces covered with randomly distri... more The problem of light trapping engineering for semiconductor surfaces covered with randomly distributed spheroidal metallic nanoparticles has been considered. The absorption of incident light by such a structure has been calculated using the Green functions method, involving the concept of an effective susceptibility. A target function, optimizing broad-band light absorption throughout the visible range has been constructed taking the geometry of the structure as the control parameters. The optimization problem of light-trapping in such structure has been solved, and the optimum nanoparticle coverage for matching the required shape of absorption spectra has been obtained. Our results can be applied to the design of plasmonic-enhanced light-collecting elements in solar cells.
2021 IEEE 16th International Conference on the Experience of Designing and Application of CAD Systems (CADSM), 2021
Present studies is devoted to optimization problem of the morphology of thin layered nanocomposit... more Present studies is devoted to optimization problem of the morphology of thin layered nanocomposite Teflon films. By the use of the information about the shape of nanoparticles and their concentration near configurational resonances for single layer film the model of multilayered Teflon films, which well absorb in the visible range of external light, was proposed. Results of theoretical studies of present paper can be linked with further experiments and can be useful to suggest possible guided instructions to provide experimental investigations.
2019 IEEE 39th International Conference on Electronics and Nanotechnology (ELNANO), 2019
The problem of optimization of morphology of nanocomposite thin films with spheroid metallic nano... more The problem of optimization of morphology of nanocomposite thin films with spheroid metallic nanoinclusions was considered. The function of quadratic deviation from willing spectrum of absorption was used as target function. To optimize morphology of nanocomposite films, the pattern search was applied. The optimal morphologies of nanocomposite thin films were obtained. Theoretically optimized nanocomposite thin films effectively transmitted external light in all visible range
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