Impressive progress has been made in the processing and exploration of new material on an atomic scale (nanomaterials). However, the characterization of such materials by the usual transmission electron microscopy (TEM) techniques suffers from the drawback that the phase of the object-modulated electron wave is virtually lost in the recorded intensity images. Electron holography has opened possibilities for analyzing both the amplitude and phase of the electron wave, hence giving access to the object information encoded in the phase. Examples include intrinsic electric and magnetic fields, e.g. in ferroelectrics or ferromagnetics, which substantially determine the object properties and therefore are indispensable for a complete understanding of structure-properties relations.

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The synthesis and production of thermoelectrical active ceramic materials, the concepts of the module design by simulation, the assembly of modules by laser joining, and the investigations concerning the operation modes are described in this paper. Investigations of the material structure, the phase composition, and the thermoelectrical properties illustrate the material development. The newly developed technological route is described. The simulated results of thermoelectric modules for operational cases are compared with gained experimental data.

Transmission electron microscopy (TEM) is a widely used tool for analysis of very large scale integrated (VLSI) semiconductor devices. As a special TEM-feature, off-axis electron holography obtains information about the electrical characteristics of a specimen, which are connected to the dopant concentration in the bulk material. Compared with conventional TEM, application of electron holography for dopant profiling demands a higher quality of specimen preparation, e.g. in terms of thickness homogeneity. Since preparation by means of focused ion beam (FIB) has become an industrial standard for TEM-investigations, its facilities are investigated for meeting the high holographic demands. It turned out that, besides many advantages like precision and speed, the use of FIB for preparation introduces new specific problems, e.g. it is hardly possible to visualize doped areas of semiconductors on a classical, thin FIB specimen. Additionally, some artifacts of FIB-preparation have no great importance for normal TEM analysis, but do significantly influence the results of holographic analysis. In order to satisfy the higher demands of preparation for holography, a special procedure for FIB-preparation has been newly developed.

Published by the AIP PublishingArticles you may be interested in Gas source molecular beam epitaxy of scandium nitride on silicon carbide and gallium nitride surfaces J. Vac. Sci. Technol. A 32, 061504 (2014); 10.1116/1.4894816Extending the detection limit of dopants for focused ion beam prepared semiconductor specimens examined by off-axis electron holography

Short electron pulses with high energy are a very promising tool for the controlled ablation and deposition of materials. The plasmas induced by the electron beam irradiation are distinguished by their high degree of ionization and excitation. A source for pulsed electron beam is the channel spark device. It delivers pulsed high current and self-focused electron beams (about 15 keV, 1 kA, 100 ns). For deposition technology, the plasma beam is the decisive element of the pulsed vapor deposition (PVD) equipment. Hence, the characteristics of the plasma and its dependence on the primary irradiation are of principal importance. The development of the plasma has been characterized by the emitted optical radiation, spectral resolved. Since the energy of the electron beam is not constant during the pulse, the plasma of the channel spark shows strong variations in its temperature and degree of ionization. In the following, spectral-resolved snapshot pictures of the plasma are represented. Cons idering the short pulse times and the small dimensions, a special high-speed camera combining high-temporal, high-spatial and high-spectral resolution has been applied

To form embedded Fe nanoparticles, MgO(001) and YSZ(001) single crystals have been implanted at elevated temperatures with Fe ions at energies of 100keV and 110keV, respectively. The ion fluence was fixed at 6×1016cm−2. As a result, γ- and α-phase Fe nanoparticles were synthesized inside MgO and YSZ, respectively. A synthesis efficiency of 100% has been achieved for implantation at 1273K into YSZ. The ferromagnetic behavior of the α-Fe nanoparticles is reflected by a magnetic hyperfine field of 330kOe and a hysteretic magnetization reversal. Electron holography showed a fringing magnetic field around some, but not all of the particles.