Gold nanowires with diameters ranging from 20 to 90 nm were fabricated by the electrochemical dep... more Gold nanowires with diameters ranging from 20 to 90 nm were fabricated by the electrochemical deposition technique in etched ion track polycarbonate templates and were then irradiated by Xe and Kr ions with the energy in MeV range. The surface modification of nanowires was studied by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) characterizations. Different craters with and without protrusion on the gold nanowires were analyzed, and the two corresponding formation mechanisms, i.e., plastic flow and micro-explosion, were investigated. In addition, the sputtered gold nanoparticles caused by ion irradiation were studied and it was confirmed that the surface damage produced in gold nanowires was increased as the diameter of the nanowires decreased. It was also found that heavy ion irradiation can also create stacking fault tetrahedrons (SFTs) in gold nanowires and three different SFTs were confirmed in irradiated nanowires. A statistical analysis of the s...
Graphene is an ideal candidate for the development of solid state nanopores due to its thickness ... more Graphene is an ideal candidate for the development of solid state nanopores due to its thickness at the atomic scale and its high chemical and mechanical stabilities. A facile method was adopted to prepare single graphene nanopore supported by PET membrane (G/PET nanopore) within the three steps assisted by the swift heavy ion irradiation and asymmetric etching technology. The inversion of the ion rectification effect was confirmed in G/PET nanopore while comparing with bare PET nanopore in KCl electrolyte solution. By modifying the wall charge state of PET conical nanopore with hydrochloric acid from negative to positive, the ion rectification effect of G/PET nanopore was found to be greatly enhanced and the large rectification ratio up to 190 was obtained during this work. Moreover, the high ionic flux and high ion separation efficiency was also observed in the G/PET nanopore system. By comparing the "on" and "off" state conductance of G/PET nanopore while imme...
Modification of polyethylene terephthalate (PET) was carried out by 120 keV Ar +, 240 keV Ar 2+ a... more Modification of polyethylene terephthalate (PET) was carried out by 120 keV Ar +, 240 keV Ar 2+ and 360 keV Ar 3+ ions implantation. From measurement of UV absorption, optical band gaps under various implantation conditions were deduced with Tauc's plot. A dramatic decrease about 8 orders of magnitude of the sheet resistivity ( ρs) was obtained and explained by the progressive narrowing of the band gap. Friction and wear behaviors of argon ion implanted PET against steel ball were investigated. The change of surface atom and molecular radical of irradiated PET was characterized by X-ray photoelectron spectroscopy. All results suggest that irradiation damage attributes to energy transferred by electronic excitation or ionization. The conducting property induced by implantation is attributed to the formation of conduction states in the pristine band gap.
Nuclear Instruments and Methods in Physics Research Section B Beam Interactions With Materials and Atoms, Aug 1, 2003
Polycarbonate (Makrofol kg) film stacks were irradiated by 15.14 MeV/amu Xe 136 and 11.4 MeV/amu ... more Polycarbonate (Makrofol kg) film stacks were irradiated by 15.14 MeV/amu Xe 136 and 11.4 MeV/amu U 238 in the electronic stopping power range (7.6-17.1 keV/nm) and the fluence range from 9×10 9 to 1×10 12 ions/cm 2. The chemical degradation of the function group was investigated by Fourier-transform infrared (FTIR) spectroscopy and the crystallinity was analyzed by X-ray diffraction (XRD) measurement. FTIR results reveal that the material suffers serious degradation after irradiation. The alkyne group was found after irradiation and their formation cross-sections were evaluated. XRD measurements show the decrease of the main XRD peak intensity, confirming that the material to be amorphised under irradiation. The ion induced amorphisation cross-section was extracted from the fitting of the experimental data for different electronic energy loss irradiations. The degradation cross-section, the formation cross-section and the amorphisation cross-section versus electronic energy loss were discussed.
2013 14th European Conference on Radiation and Its Effects on Components and Systems, Sep 1, 2013
ABSTRACT The effects of temperature on the single-event upset (SEU) response of commercial and ra... more ABSTRACT The effects of temperature on the single-event upset (SEU) response of commercial and radiation-hardened SRAMs are investigated by experiment. The results showed that the SEU sensitivity relied on the temperature during the testing. However, it was also observed the amplitude of energy deposition of ions in sensitive volume of SRAM devices is able to affect the SEU sensitivity. When the deposited energy in sensitive volume is far larger than the critical value of inducing a SEU occurrence, the SEU sensitivity both in Bulk and SOI technologies displays a less temperature dependency. This result is attributed to the impact of energy deposition on the ion-induced transient pulse shape. The deposited energy in sensitive volume by different ions was estimated by Monte Carlo simulation and the role of energy deposition in transient pulse shape was discussed. The conclusion of detailed analysis is agreement with the results obtained in experiments.
Single crystals of alpha-alumina were irradiated at room temperature with 1.157 GeV 56Fe, 1.755 G... more Single crystals of alpha-alumina were irradiated at room temperature with 1.157 GeV 56Fe, 1.755 GeV 136Xe and 2.636 GeV 238U ions to fluences range from 8.7 × 109 to 6 × 1012 ions/cm2. Virgin and irradiated samples were investigated by ultraviolet-visible absorption measurements. The investigation reveals the presence of various color centers (F,F+, F22+, F2+ and F2 centers) appearing in the irradiated samples. It is found that the ratio of peak absorbance of F2 to F centers increases with the increase of the atomic numbers of the incident ions from Fe, Xe to U ions, so do the absorbance ratio of F 22+ to F+ centers and of large defect cluster to F centers, indicating that larger defect clusters are preferred to be produced under heavier ion irradiation. Largest color center production cross-section was found for the U ion irradiation. The number density of single anion vacancy scales better with the energy deposition through processes of nuclear stopping, indicating that the nuclear energy loss processes determines the production of F-type defects in heavy ion irradiated alpha-alumina.
Abstract In this paper, an investigation on the micro-structure of an Fe-base oxide-dispersion-st... more Abstract In this paper, an investigation on the micro-structure of an Fe-base oxide-dispersion-strengthened (ODS) alloy irradiated with high-energy 20 Ne ions to different doses at a temperature around 0.5T m (T m is the melting point of the alloy) is presented. ...
Silicon samples were irradiated below 50 K with 112 MeV Ar ions. Defect production was investigat... more Silicon samples were irradiated below 50 K with 112 MeV Ar ions. Defect production was investigated at room temperature by EPR and infrared optical absorption techniques. The EPR measurements reveal the presence of amorphous zones and neutral tetravacancies (Si-P3 center) in the as-irradiated samples. The infrared optical absorption measurements indicate the formation of divacancy. The concentration of divacancy increases with ion fluence and saturates at high fluence. The isochronal annealing behaviors of the radiation induced defect centers are found to be fluence dependent. For 1.0 × 10 14/cm 2 irradiated sample, the disappearance of the Si-P3 center is accompanied by the appearance of Si-P1 and Si-B2 centers and the growth of Si-A11 center. The Si-P1 center and the isolated amorphous regions are annealed out between 500°C and 550°C. The Si-A11 center is stable up to 600°C. For 8.0 × 10 14/cm 2 irradiated sample, only Si-P1 center and the line due to the continued amorphous layer are detected above 200°C. The recrystallization of the continued amorphous layer occurs at temperature higher than 600°C.
Understanding and controlling structural properties of the materials are crucial in materials res... more Understanding and controlling structural properties of the materials are crucial in materials research. In this paper, we report that crystallinity and crystallographic orientation of Pd nanowires can be tailored by varying the fabrication conditions during electrochemical deposition in polycarbonate ion-track templates. By changing the deposition temperature during the fabrication process, the nanowires with both single- and poly-crystallinities were obtained. The wires with preferred crystallographic orientations along [111], [100], and [110] directions were achieved via adjusting the applied voltage and temperature during electrochemical deposition.
2013 14th European Conference on Radiation and Its Effects on Components and Systems (RADECS), 2013
ABSTRACT The effects of temperature on the single-event upset (SEU) response of commercial and ra... more ABSTRACT The effects of temperature on the single-event upset (SEU) response of commercial and radiation-hardened SRAMs are investigated by experiment. The results showed that the SEU sensitivity relied on the temperature during the testing. However, it was also observed the amplitude of energy deposition of ions in sensitive volume of SRAM devices is able to affect the SEU sensitivity. When the deposited energy in sensitive volume is far larger than the critical value of inducing a SEU occurrence, the SEU sensitivity both in Bulk and SOI technologies displays a less temperature dependency. This result is attributed to the impact of energy deposition on the ion-induced transient pulse shape. The deposited energy in sensitive volume by different ions was estimated by Monte Carlo simulation and the role of energy deposition in transient pulse shape was discussed. The conclusion of detailed analysis is agreement with the results obtained in experiments.
Gold nanowires with diameters ranging from 20 to 90 nm were fabricated by the electrochemical dep... more Gold nanowires with diameters ranging from 20 to 90 nm were fabricated by the electrochemical deposition technique in etched ion track polycarbonate templates and were then irradiated by Xe and Kr ions with the energy in MeV range. The surface modification of nanowires was studied by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) characterizations. Different craters with and without protrusion on the gold nanowires were analyzed, and the two corresponding formation mechanisms, i.e., plastic flow and micro-explosion, were investigated. In addition, the sputtered gold nanoparticles caused by ion irradiation were studied and it was confirmed that the surface damage produced in gold nanowires was increased as the diameter of the nanowires decreased. It was also found that heavy ion irradiation can also create stacking fault tetrahedrons (SFTs) in gold nanowires and three different SFTs were confirmed in irradiated nanowires. A statistical analysis of the s...
Graphene is an ideal candidate for the development of solid state nanopores due to its thickness ... more Graphene is an ideal candidate for the development of solid state nanopores due to its thickness at the atomic scale and its high chemical and mechanical stabilities. A facile method was adopted to prepare single graphene nanopore supported by PET membrane (G/PET nanopore) within the three steps assisted by the swift heavy ion irradiation and asymmetric etching technology. The inversion of the ion rectification effect was confirmed in G/PET nanopore while comparing with bare PET nanopore in KCl electrolyte solution. By modifying the wall charge state of PET conical nanopore with hydrochloric acid from negative to positive, the ion rectification effect of G/PET nanopore was found to be greatly enhanced and the large rectification ratio up to 190 was obtained during this work. Moreover, the high ionic flux and high ion separation efficiency was also observed in the G/PET nanopore system. By comparing the "on" and "off" state conductance of G/PET nanopore while imme...
Modification of polyethylene terephthalate (PET) was carried out by 120 keV Ar +, 240 keV Ar 2+ a... more Modification of polyethylene terephthalate (PET) was carried out by 120 keV Ar +, 240 keV Ar 2+ and 360 keV Ar 3+ ions implantation. From measurement of UV absorption, optical band gaps under various implantation conditions were deduced with Tauc's plot. A dramatic decrease about 8 orders of magnitude of the sheet resistivity ( ρs) was obtained and explained by the progressive narrowing of the band gap. Friction and wear behaviors of argon ion implanted PET against steel ball were investigated. The change of surface atom and molecular radical of irradiated PET was characterized by X-ray photoelectron spectroscopy. All results suggest that irradiation damage attributes to energy transferred by electronic excitation or ionization. The conducting property induced by implantation is attributed to the formation of conduction states in the pristine band gap.
Nuclear Instruments and Methods in Physics Research Section B Beam Interactions With Materials and Atoms, Aug 1, 2003
Polycarbonate (Makrofol kg) film stacks were irradiated by 15.14 MeV/amu Xe 136 and 11.4 MeV/amu ... more Polycarbonate (Makrofol kg) film stacks were irradiated by 15.14 MeV/amu Xe 136 and 11.4 MeV/amu U 238 in the electronic stopping power range (7.6-17.1 keV/nm) and the fluence range from 9×10 9 to 1×10 12 ions/cm 2. The chemical degradation of the function group was investigated by Fourier-transform infrared (FTIR) spectroscopy and the crystallinity was analyzed by X-ray diffraction (XRD) measurement. FTIR results reveal that the material suffers serious degradation after irradiation. The alkyne group was found after irradiation and their formation cross-sections were evaluated. XRD measurements show the decrease of the main XRD peak intensity, confirming that the material to be amorphised under irradiation. The ion induced amorphisation cross-section was extracted from the fitting of the experimental data for different electronic energy loss irradiations. The degradation cross-section, the formation cross-section and the amorphisation cross-section versus electronic energy loss were discussed.
2013 14th European Conference on Radiation and Its Effects on Components and Systems, Sep 1, 2013
ABSTRACT The effects of temperature on the single-event upset (SEU) response of commercial and ra... more ABSTRACT The effects of temperature on the single-event upset (SEU) response of commercial and radiation-hardened SRAMs are investigated by experiment. The results showed that the SEU sensitivity relied on the temperature during the testing. However, it was also observed the amplitude of energy deposition of ions in sensitive volume of SRAM devices is able to affect the SEU sensitivity. When the deposited energy in sensitive volume is far larger than the critical value of inducing a SEU occurrence, the SEU sensitivity both in Bulk and SOI technologies displays a less temperature dependency. This result is attributed to the impact of energy deposition on the ion-induced transient pulse shape. The deposited energy in sensitive volume by different ions was estimated by Monte Carlo simulation and the role of energy deposition in transient pulse shape was discussed. The conclusion of detailed analysis is agreement with the results obtained in experiments.
Single crystals of alpha-alumina were irradiated at room temperature with 1.157 GeV 56Fe, 1.755 G... more Single crystals of alpha-alumina were irradiated at room temperature with 1.157 GeV 56Fe, 1.755 GeV 136Xe and 2.636 GeV 238U ions to fluences range from 8.7 × 109 to 6 × 1012 ions/cm2. Virgin and irradiated samples were investigated by ultraviolet-visible absorption measurements. The investigation reveals the presence of various color centers (F,F+, F22+, F2+ and F2 centers) appearing in the irradiated samples. It is found that the ratio of peak absorbance of F2 to F centers increases with the increase of the atomic numbers of the incident ions from Fe, Xe to U ions, so do the absorbance ratio of F 22+ to F+ centers and of large defect cluster to F centers, indicating that larger defect clusters are preferred to be produced under heavier ion irradiation. Largest color center production cross-section was found for the U ion irradiation. The number density of single anion vacancy scales better with the energy deposition through processes of nuclear stopping, indicating that the nuclear energy loss processes determines the production of F-type defects in heavy ion irradiated alpha-alumina.
Abstract In this paper, an investigation on the micro-structure of an Fe-base oxide-dispersion-st... more Abstract In this paper, an investigation on the micro-structure of an Fe-base oxide-dispersion-strengthened (ODS) alloy irradiated with high-energy 20 Ne ions to different doses at a temperature around 0.5T m (T m is the melting point of the alloy) is presented. ...
Silicon samples were irradiated below 50 K with 112 MeV Ar ions. Defect production was investigat... more Silicon samples were irradiated below 50 K with 112 MeV Ar ions. Defect production was investigated at room temperature by EPR and infrared optical absorption techniques. The EPR measurements reveal the presence of amorphous zones and neutral tetravacancies (Si-P3 center) in the as-irradiated samples. The infrared optical absorption measurements indicate the formation of divacancy. The concentration of divacancy increases with ion fluence and saturates at high fluence. The isochronal annealing behaviors of the radiation induced defect centers are found to be fluence dependent. For 1.0 × 10 14/cm 2 irradiated sample, the disappearance of the Si-P3 center is accompanied by the appearance of Si-P1 and Si-B2 centers and the growth of Si-A11 center. The Si-P1 center and the isolated amorphous regions are annealed out between 500°C and 550°C. The Si-A11 center is stable up to 600°C. For 8.0 × 10 14/cm 2 irradiated sample, only Si-P1 center and the line due to the continued amorphous layer are detected above 200°C. The recrystallization of the continued amorphous layer occurs at temperature higher than 600°C.
Understanding and controlling structural properties of the materials are crucial in materials res... more Understanding and controlling structural properties of the materials are crucial in materials research. In this paper, we report that crystallinity and crystallographic orientation of Pd nanowires can be tailored by varying the fabrication conditions during electrochemical deposition in polycarbonate ion-track templates. By changing the deposition temperature during the fabrication process, the nanowires with both single- and poly-crystallinities were obtained. The wires with preferred crystallographic orientations along [111], [100], and [110] directions were achieved via adjusting the applied voltage and temperature during electrochemical deposition.
2013 14th European Conference on Radiation and Its Effects on Components and Systems (RADECS), 2013
ABSTRACT The effects of temperature on the single-event upset (SEU) response of commercial and ra... more ABSTRACT The effects of temperature on the single-event upset (SEU) response of commercial and radiation-hardened SRAMs are investigated by experiment. The results showed that the SEU sensitivity relied on the temperature during the testing. However, it was also observed the amplitude of energy deposition of ions in sensitive volume of SRAM devices is able to affect the SEU sensitivity. When the deposited energy in sensitive volume is far larger than the critical value of inducing a SEU occurrence, the SEU sensitivity both in Bulk and SOI technologies displays a less temperature dependency. This result is attributed to the impact of energy deposition on the ion-induced transient pulse shape. The deposited energy in sensitive volume by different ions was estimated by Monte Carlo simulation and the role of energy deposition in transient pulse shape was discussed. The conclusion of detailed analysis is agreement with the results obtained in experiments.
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