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AIP Conference Proceedings, 2019
Oblique ion beam induced modifications in polymeric materials can be treated as an indispensable ... more Oblique ion beam induced modifications in polymeric materials can be treated as an indispensable tool for fabrication of advanced functional materials having wide range of technological applications. In this context, we have examined the influence of 100 keV argon ion irradiation on optical and structural properties of Polycarbonate (PC) polymer at various oblique incidences of 30 0 , 40 0 and 50 0. UV-visible analysis reveals that optical absorption edge shifted towards the visible region of the spectrum with decrease in angle of incidence which indicate towards the decrease in optical energy gap. A significant increase in Urbach energy (disorder content) from 0.09 eV to 0.795 eV has been observed. Interestingly, with decrease in angle of incidence optical energy gap decreases from 3.06 eV (virgin) to 2.45 eV at lowest angle of 30 0. Moreover, FTIR transmission spectra shows drastic alterations in transmittance which are associated with structural modifications as a result of oblique ion irradiation. Further, the size of carbon clusters is found to be enhanced with decrease in angle of incidence. The observed optical changes have been further correlated with the structural modifications in the polymeric matrix as a result of oblique ion irradiation.
Integrated Ferroelectrics
Journal of Applied Physics
Oblique ion beam induced spontaneous patterning opens up a simple and inexpensive route to fabric... more Oblique ion beam induced spontaneous patterning opens up a simple and inexpensive route to fabricate useful nanoscale textured materials that have important implications in biosensors, optoelectronic devices, templates for liquid crystal orientation, etc. In this regard, the evolution of patterns over high density polyethylene surfaces induced by 100 keV Ar + irradiation at off normal incidences of 30°, 40°, and 50°w ith a fluence of 5 × 10 16 Ar + cm −2 has been investigated. Structural modifications have been analyzed using high resolution X-ray diffraction. An increase in crystallite size and a decrease in parameters such as dislocation density (δ), microstrain (ϵ), and distortion (g) have been observed after oblique Ar + irradiation with an increase in the angle of incidence from 30°to 40°. Atomic force microscopy analysis revealed that the wavelength of ripplelike patterns decreases from 3.19 μm to 2.51 μm, while its amplitude increases from 77.4 nm to 101 nm with an increase in the angle of incidence from 30°to 40°. Similarly, with an increase of oblique incidence to 40°, the root mean square (R q) and average surface roughness (R av) have been found to increase. These results are accredited to the curvature dependent sputtering and smoothing processes at oblique incidences. The possible correlation between ion beam sputtering induced patterning and the structural modification in the matrix has been established and discussed.
DAE SOLID STATE PHYSICS SYMPOSIUM 2018
In the present study irradiation of High Density Polyethylene (HDPE) by100 keV Argon ions as a fu... more In the present study irradiation of High Density Polyethylene (HDPE) by100 keV Argon ions as a function of different oblique incidences has been carried out in order to evaluate the optical and structural modifications induced in the polymer. Specimens were irradiated at various oblique incidences of 30 0 , 40 0 and 50 0 with a fluence of 5x10 16 Ar + cm-2. Raman analysis reveal that with angle of incidence the intensity of most of the fundamental bands decrease significantly, which is ascribed to structural modifications as a result of oblique Ar + irradiation. The UV-visible analysis shows a prominent increase in absorption along with a red shift in absorption edge. Optical band gap has been found to decrease significantly from 2.54 eV to 1.65 eV but with subsequent increase in oblique incidence, it increased to 2.38 eV. Interestingly, the value of Urbach energy (disorder parameter) has been found to increase after ion irradiation. Furthermore, the observed significant alterations in UV-visible transmission spectra were consistent with changes in optical absorption and surface colour of irradiated samples. Such oblique ion beam induced structural and optical modifications have important implications in fabrication of selective frequency filters, optical sensors and wave guides etc.
AIP Conference Proceedings, 2019
Oblique ion beam induced modifications in polymeric materials can be treated as an indispensable ... more Oblique ion beam induced modifications in polymeric materials can be treated as an indispensable tool for fabrication of advanced functional materials having wide range of technological applications. In this context, we have examined the influence of 100 keV argon ion irradiation on optical and structural properties of Polycarbonate (PC) polymer at various oblique incidences of 30 0 , 40 0 and 50 0. UV-visible analysis reveals that optical absorption edge shifted towards the visible region of the spectrum with decrease in angle of incidence which indicate towards the decrease in optical energy gap. A significant increase in Urbach energy (disorder content) from 0.09 eV to 0.795 eV has been observed. Interestingly, with decrease in angle of incidence optical energy gap decreases from 3.06 eV (virgin) to 2.45 eV at lowest angle of 30 0. Moreover, FTIR transmission spectra shows drastic alterations in transmittance which are associated with structural modifications as a result of oblique ion irradiation. Further, the size of carbon clusters is found to be enhanced with decrease in angle of incidence. The observed optical changes have been further correlated with the structural modifications in the polymeric matrix as a result of oblique ion irradiation.
Integrated Ferroelectrics
Journal of Applied Physics
Oblique ion beam induced spontaneous patterning opens up a simple and inexpensive route to fabric... more Oblique ion beam induced spontaneous patterning opens up a simple and inexpensive route to fabricate useful nanoscale textured materials that have important implications in biosensors, optoelectronic devices, templates for liquid crystal orientation, etc. In this regard, the evolution of patterns over high density polyethylene surfaces induced by 100 keV Ar + irradiation at off normal incidences of 30°, 40°, and 50°w ith a fluence of 5 × 10 16 Ar + cm −2 has been investigated. Structural modifications have been analyzed using high resolution X-ray diffraction. An increase in crystallite size and a decrease in parameters such as dislocation density (δ), microstrain (ϵ), and distortion (g) have been observed after oblique Ar + irradiation with an increase in the angle of incidence from 30°to 40°. Atomic force microscopy analysis revealed that the wavelength of ripplelike patterns decreases from 3.19 μm to 2.51 μm, while its amplitude increases from 77.4 nm to 101 nm with an increase in the angle of incidence from 30°to 40°. Similarly, with an increase of oblique incidence to 40°, the root mean square (R q) and average surface roughness (R av) have been found to increase. These results are accredited to the curvature dependent sputtering and smoothing processes at oblique incidences. The possible correlation between ion beam sputtering induced patterning and the structural modification in the matrix has been established and discussed.
DAE SOLID STATE PHYSICS SYMPOSIUM 2018
In the present study irradiation of High Density Polyethylene (HDPE) by100 keV Argon ions as a fu... more In the present study irradiation of High Density Polyethylene (HDPE) by100 keV Argon ions as a function of different oblique incidences has been carried out in order to evaluate the optical and structural modifications induced in the polymer. Specimens were irradiated at various oblique incidences of 30 0 , 40 0 and 50 0 with a fluence of 5x10 16 Ar + cm-2. Raman analysis reveal that with angle of incidence the intensity of most of the fundamental bands decrease significantly, which is ascribed to structural modifications as a result of oblique Ar + irradiation. The UV-visible analysis shows a prominent increase in absorption along with a red shift in absorption edge. Optical band gap has been found to decrease significantly from 2.54 eV to 1.65 eV but with subsequent increase in oblique incidence, it increased to 2.38 eV. Interestingly, the value of Urbach energy (disorder parameter) has been found to increase after ion irradiation. Furthermore, the observed significant alterations in UV-visible transmission spectra were consistent with changes in optical absorption and surface colour of irradiated samples. Such oblique ion beam induced structural and optical modifications have important implications in fabrication of selective frequency filters, optical sensors and wave guides etc.