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SummaryThe dual-beam microscope is a combination of a focused ion beam with an electron beam. The instrument used in this work is also equipped with an energy-dispersive X-ray system for local elemental analysis. This powerful tool gives access to specific features inside a material. Two different applications are presented in this paper: (1) cross-sections and transmission electron microscope specimens cut in order to investigate the interface between an aluminium substrate and its epoxy coating; and (2) a grain boundary in a Cu 3 Au alloy. In both cases, the dual beam succeeded where other methods failed.

We have investigated the dielectric properties of thin layers of five oxides of transition metals (Ta 2 O 5 , HfO 2 , ZrO 2 , (ZrO 2 ) 0.91 (Y 2 O 3 ) 0.09 , and Sn 0.2 Zr 0.2 Ti 0.6 O 2 ) sputtered from ceramic targets at different pressures. We find that layers deposited at low pressure behave as expected from literature, whereas layers deposited at high pressure all exhibit an anomalous dielectric response similar to that reported for the so-called ''colossal'' dielectric constant materials. The characterization of the thickness, frequency, and temperature dependence of the capacitance, as well as the comparison of film properties before and after annealing show that the anomalous dielectric response is due to quenched-in vacancies that act as dopants and cause the insulating layers to behave as semiconductors. An increase in quenched-in vacancies concentration with sputtering pressure results in a transition from normal to anomalous dielectric response and gradual increase in layer conductivity. In contrast, the refractive index does not depend on sputtering pressure. This observation indicates the possible application of these materials as transparent coatings with a tunable electrical conductivity.

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The 1/f noise in three types of aluminum lines has been investigated in the temperature range 140-510 K. The types are one long single crystal, a chain of short single crystals ͑''bamboo''͒, and a polycrystal. In the lines of the first two types the 1/f noise power is significantly lower than in the polycrystalline specimens. The temperature dependence of the noise power in the polycrystalline lines shows a plateau between 370 and 415 K, corresponding to activation energies 0.9-1.0 eV. Both types of monocrystalline lines have equal noise power with a peak around 340 K, corresponding to an activation energy of about 0.8 eV. In the polycrystalline lines the dominant contribution to 1/f noise appears to be the thermally activated motion of atoms in grain boundaries. The measurements on the monocrystalline lines reveal the existence of at least one further contribution to 1/f noise in metals, presumably associated with the thermally activated diffusion of atoms along dislocations.