Fabrication of a multistrip magnetic/nonmagnetic structure in a thin sandwiched Ni layer [Si(5 nm)/Ni(15 nm)/Si] by a focused ion beam (FIB) irradiation has been attempted. A control experiment was initially performed by irradiation with a standard 30 keV Ga ion beam at various fluences. Analyses were carried out by Rutherford backscattering spectrometry, X-ray reflectivity, magnetooptical Kerr effect (MOKE) measurements and MOKE microscopy. With increasing ion fluence, the coercivity as well as Kerr rotation decreases. A threshold ion fluence has been identified, where ferromagnetism of the Ni layer is lost at room temperature and due to Si incorporation into the Ni layer, a Ni 0.68 Si 0.32 alloy layer is formed. This fluence was used in FIB irradiation of parallel 50 nm wide stripes, leaving 1 µm wide unirradiated stripes in between. MOKE microscopy on this FIB-patterned sample has revealed interacting magnetic domains across several stripes. Considering shape anisotropy effects, which would favour an alignment of magnetization parallel to the stripe axis, the opposite behaviour is observed. Magneto-elastic effects introducing a stress-induced anisotropy component oriented perpendicular to the stripe axis are the most plausible explanation for the observed behaviour.

The compound formation in the ternary system Pr–Si–O initiated by ion beam synthesis inside bulk-Si was studied by transmission electron microscopy and X-ray diffraction. The oxygen content was varied by additional O+ ion implantation and by oxidation of the bulk-Si. For annealing temperatures of 1100°C, Pr silicate nanoclusters were observed consisting of Pr9.33Si6O26 or Pr2Si2O7. These silicates were the dominating and most stable Pr compounds. The interfaces between Pr silicate and the crystalline Si were atomically abrupt after high-temperature annealing. Pr silicide (PrSi2) was detected for lower annealing temperatures such as 900°C and for higher annealing temperatures in minor fraction also in samples with enhanced O content. Pr oxide (Pr2O3), the promising high-k material, was not definitely verified. In ion beam synthesis, the energy related to structural reordering during solid-state compound formation is a parameter that controls the proceeding processes in addition to other parameters like chemical reactivity and the compound interface matching.

Structural and ferromagnetic properties in Mn implanted, p-type Si were investigated. High resolution structural analysis techniques like synchrotron X-ray diffraction revealed the formation of MnSi1.7 nanoparticles already in the as implanted samples. Depending on the Mn-fluence, the size increases from 5 nm to 20 nm upon rapid thermal annealing. No significant evidence is found for Mn substituting Si sites either in the as-implanted or annealed samples. The observed ferromagnetism yields a saturation moment of 0.21 mu_B per implanted Mn at 10 K, which could be assigned to MnSi1.7 nanoparticles as revealed by a temperature dependent magnetization measurement.

Room-temperature ferromagnetism has been induced within ZnO single crystals by implant-doping with Fe ions.The four samples implanted initially have been analyzed using SQUID (superconducting quantum interference device) magne-tometry. It was found that only two of them, i.e. the HFHT and the LFLT samples exhibit a pronounced hysteresis loop upon magnetization reversal at 5 K and 300 K. As was found using synchrotron X-ray diffraction, transmission electron microscopy and conversion electron Mossbauer spectroscopy (CEMS) the origin of the ferromagnetic properties of the HFHT-sample are tiny alpha-Fe-nanoparticles with a mean diameter of 8 nm. At 180 keV Fe implanted ZnO single crystals can develop ferromagnetic properties that are either caused by alpha-Fe nanoparticles or an indirect coupling of the Fe ions in a DMS system, depending on the details of ion fluence and implantation temperature. In any case sophisticated structural characterization is required in order to rule out secondary phases.

CoFe single and multi-layer systems are deposited by a radio-frequency sputter process. Thickness, roughness, morphology, texture and internal stress state of the layers are determined by X-ray reflectometry, transmission electron microscopy, and diffraction methods. The texture and the internal stress of the layers depend strongly on the parameters of the sputter process. The magnetic properties of the layers are determined from hysteresis curve measurements and magneto-optical Kerr microscopy. A strong correlation between the texture, the internal stress, and the magnetic properties of the CoFe layers is observed.

The possibilities and limitations of X-ray scattering techniques are discussed for the structure analysis of TaN barriers for Cu metallization. Diffraction measurements under grazing incident angle enable to analyze the phase composition and to determine structural parameters of 10 nm TaN films onto (100)-silicon wafers. Depending on the nitrogen flow nanocrystalline bcc Ta(N) , fcc TaN, and amorphous Ta(N) phases were observed in the sputtered films. X-ray specular reflectivity measurements were explored to estimate film thickness and roughness as a function of preparation in a good agreement with transmission electron microscopy investigations.

Thin boron nitride films were deposited using ion beam assisted deposition. The fraction of the cubic phase relative to the non-cubic phase was varied by changing the assisting ion to boron atom arrival ratio during deposition. Different ex situ analytical techniques were used to resolve the layered growth, i.e. cubic BN on top of non-cubic BN. Variation of the argon incorporation measured with Rutherford backscattering spectroscopy yields information on the layered growth. Polarized IR reflection data were analysed with a multilayer model taking into account the anisotropy of hexagonal BN. The parameters of the optical model, such as the thickness of the non-cubic BN interlayer and the volume fraction of cubic BN in the toplayer, are more useful for the characterization of BN films than the established IR peak ratio. Reflection electron energy loss spectroscopy and X-ray reflectivity measurements were also performed to verify the results.

Neodymium gallium perovskite single crystals grown with the Czochralski method were examined with several complementary X-ray methods. By means of X-ray diffraction topography and reciprocal space diagram the structural perfection and crystal homogeneity of the studied wafers were determined. Additionally, the results of the X-ray reflectometry investigations of the surface perfection after the mechanochemical treatment are presented.