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The creation of conducting nanowires, parallel to each other in fullerene films by the heavy ion irradiation is described. The results have shown that the irradiation through a nanodimension mask can create a two-dimensional regular pattern of conducting nanochannels with a possibility of variety of applications.

The effect of the density of ion-induced electronic excitations on the nucleation of Fe particles in a silicon-based gel and on the magnetic ordering in SiO2:Fe composites with a volume fraction of metal of a few percent derived from the same gel is examined. Irradiation-induced changes in the magnetic anisotropy of composite films depend on the order of magnitude of electronic energy loss S(sub e).

The spray pyrolyzed ZnO film samples are irradiated using 120 MeV Au ion beam and then characterized using optical absorption and transmission, x-ray diffraction (XRD), electrical resistivity measurements, x-ray photoelectron spectroscopy (XPS), and photoluminescence studies. Details of the effects of irradiation, intensity of peaks of XRD and photoluminescence, electrical restivity of the films, atomic concentration form XPS analysis and variations in carrier concentration are discussed.

ZnS:Mn is produced in nanocrystalline form by a chemical method using polyvinylpyroledone as a chemical capping agent. The study shows that the prepared pure MnS samples did not show any photoluminescence at room temperature and concludes that the observed photoluminescence is Mn(super 2+) induced in nanocrystalline ZnS host.

Electronic sputtering in polycrystalline LiF thin film by 120 MeV Ag25+ is investigated. The sputter yields of Li and F for the different thicknesses (10–265 nm) of films are measured with online elastic recoil detection analysis technique. A reduction in sputter yield, from ∼2.3×106 to 2.2×104 atoms/ion, is observed with increase in the film thickness. The trend in the experimental results can be explained in terms of size effect in thin film following inelastic thermal spike model. The confinement of energy in the film having smaller grains and lower thickness results in higher temperature causing higher sputtering yield. [ABSTRACT FROM AUTHOR]

The effect of 120 MeV Au9+ ion irradiation and thermal annealing on [W(25 Å)/Ni(25 Å)]×10 multilayers, grown on float-glass and silicon substrates, has been studied. Wide-angle x-ray diffraction studies of pristine, as well as irradiated W/Ni multilayers, show deterioration of the superlattice structure, but x-ray reflectivity (XRR) studies reveal a nearly unaffected multilayer structure. Analysis of the XRR data using “Parratt’s formalism” does show a significant increase of W/Ni interface roughness. The observed differences in wide-angle and low-angle scattering results of the irradiated W/Ni multilayers suggest significant difference in the interlayer and intralayer mixing induced by swift heavy ion irradiation. XRR results also reveal the fluence dependence of layer densification. Plane, as well as cross-sectional transmission electron microscopy, carried out in imaging and diffraction modes very clearly shows that at higher fluence the intralayer microstructure becomes nanocrystalline (1–2 nm) and at some places amorphous too. But, the definition of the W and Ni layers still remains intact. This has been understood in terms of competition between low miscibility at the W/Ni interface and ion-beam mixing kinetics. [ABSTRACT FROM AUTHOR]

Highly transparent, conducting, highly oriented, and almost single phase ZnO films have been deposited by simple e-beam evaporation method, and the deposition parameters were optimized. The films were prepared by (a) evaporation of ZnO at different substrate temperatures and (b) evaporation of ZnO at room temperature and subsequent annealing of the films in oxygen ambient at different temperatures. The characterizations of the film were performed by optical absorption spectroscopy (UV-visible), Fourier transform infrared spectroscopy, resistivity measurement, transmission electron microscopy (TEM), photoluminescence, and x-ray diffraction measurement. Absorption spectra revealed that the films were highly transparent and the band gap of the pre- and postannealed films was in good agreement with the reported values. The band gap of the films increases on increasing the substrate temperature as well as annealing temperature, whereas the resistivity of the film decreases with substrate temperature and increases with annealing temperature. Fourier transform infrared spectroscopy of ZnO films confirms the presence of Zn–O bonding. X-ray diffraction, electron diffraction, and TEM images with high resolution and Raman spectra of the films showed the formation of crystalline ZnO having wurtzite structure. [ABSTRACT FROM AUTHOR]

In an attempt to increase the Li+-ion diffusivity, poly(vinylidenefluoride-co-hexafluoropropylene)-(propylene carbonate+diethyl carbonate)-lithium perchlorate gel polymer electrolyte system has been irradiated with 70-MeV C5+-ion beam of nine different fluences. Swift heavy-ion irradiation shows enhancement in ionic conductivity at lower fluences and decrease in ionic conductivity at higher fluences with respect to unirradiated gel polymer electrolyte films. Maximum room-temperature (303 K) ionic conductivity is found to be 2×10-2 S/cm after irradiation with a fluence of 1011 ions/cm2. This interesting result could be attributed to the fact that for a particular ion beam with a given energy, a higher fluence provides critical activation energy for cross linking and crystallization to occur, which results in the decrease in ionic conductivity. X-ray-diffraction results show decrease in the degree of crystallinity upon ion irradiation at low fluences (<=1011 ions/cm2) and increase in crystallinity at higher fluences (>1011 ions/cm2). Analysis of Fourier-transform infrared spectroscopy results suggests the bond breaking at a fluence of 5×109 ions/cm2 and cross linking at a fluence of 1012 ions/cm2 and corroborate conductivity and x-ray-diffraction results. Scanning electron micrographs exhibit increased porosity of the polymer electrolyte after ion irradiation. [ABSTRACT FROM AUTHOR]

Poly(vinylideenefluoride-co-hexafluoropropylene)-(propylene carbonate=diethyl carbonate)-lithium perchlorate gel polymer electrolyte system was irradiated with 70-Mev C(super 5+) -ion beam of nine different fluences in an attempt to increase the Li(super +)-ion diffusivity. Swift heavy-ion irradiation shows enhancement in ionic conductivity at higher fluences with respect to unirradiated gel polymer electrolyte films.