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Swift heavy ion induced stress in a pulsed laser deposited textured ZnO thin film is reported. In situ X-ray diffraction (XRD) measurements are carried out during ion irradiation at incremented fluences under 120 MeV Ag(+9) ions. The average grain size, lattice constant 'c', and stress in the film are calculated from the diffraction pattern. The nature of the stress is intrinsic and the origin can be attributed to the strong density of defects like dislocations at the grain boundaries as evidenced by micro-Raman, Fourier transform infrared (FTIR) spectroscopy and Atomic Force microscopic (AFM) studies. (C) 2010 Elsevier Ltd. All rights reserved.

Three phase transitions (face centered to simple cubic, surface rearrangement from (2×2) to (1×1) and glass transition) in fullerene thin films and the effect of 150 MeV Ti ion irradiation on these transitions have been studied, using temperature dependence of electrical resistivity measurements. The structural properties of the C60 thin films are studied by X-ray diffraction, atomic force microscopy and UV–vis spectroscopy. It is observed that defect creation by ion irradiation in the films lead to quenching and broadening of structural phase transitions but the transition temperatures did not show significant shifting under ion irradiation.

We have studied the photoluminescence (PL) of inorganic polymers submitted to irradiations with increasing fluences of energetic He, C or Au ions and correlated the changes in luminescence spectra to structural transformations, evidenced by means of ion beam analyses, Raman, FTIR and spectroscopic ellipsometry. The films exhibit a strong yellow emission when the energy transferred by the ions to electron shells of target atoms is within a given range of 20 to 60 eV/atom. For this optimal amount of ionizations, the precipitation of quantum dots made of free carbon becomes noticeable. The vanishing of the luminescence for larger energy transfers is attributed to the percolation or growth of these dots, combined with a subcritical depletion in the H content of the surrounding SiO 1.5 C x : H y matrix.