We present a laser induced ablation process to fabricate ultrathin graphitic flakes. By varying the fluence of the ablating pulsed fs-laser radiation, we identify distinct values for "thermal" evaporation and so-called "non-thermal" ablation of graphitic flakes. The presence of the non-thermal ablation is a direct consequence of the strong asymmetry of the bonding strength in normal and in-plane direction in layered materials, such as graphite. The experimentally extracted non-thermal ablation threshold for graphite of 250 mJ/cm2 agrees well with theoretical predictions. Finally, we deposited ultrathin graphitic flakes of 50 μm2 in size, which we characterize by Raman spectroscopy and scanning force microscopy.

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Sputter deposition is a versatile and industrially important deposition technique for thin films, with increasing demand for matching the characteristics of thin film materials to specific requirements. The actual film properties are largely determined by sputtering parameters such as pressure conditions, temperature and power settings. By means of various X-ray diffraction and scattering techniques, it is shown that the characterization of film formation and growth is feasible in real time at synchrotron sources, thus adding an important dimension to the fundamental understanding of the evolution of thin film microstructure. In particular, grazing incidence small-angle X-ray scattering, grazing incidence X-ray powder diffraction and X-ray reflectometry are used in a complementary manner to study the influence of deposition temperature and substrate choice on the crystallization kinetics and growth of polycrystalline BaTiO 3 films.

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